🙉 👨🏾‍🚀 ↖️ आभासी कार्यों के बिना बहुरूपता 💄 🐴 🕺🏼

यह आलेख एक पैटर्न प्रस्तुत करता है जिसका उपयोग आभासी कार्यों का उपयोग किए बिना डायनेमिक बाइंडिंग प्रदान करने के लिए किया जा सकता है, जब यह ट्रैवर्स किए जाने पर विषम कंटेनर की वस्तुओं के लिए अतिभारित तरीकों को कॉल करता है।

एक परिचय के रूप में

यह आमतौर पर C ++ में प्रक्रियाओं के बीच साझा वस्तुओं का सहारा लेने के लिए अनुशंसित नहीं है, हालांकि यह संभव है। आइए जानें कि ऐसा क्यों जरूरी है:

डायनामिक बाइंडिंग में, जब किसी ऑब्जेक्ट के लिए वर्चुअल फ़ंक्शन को कॉल किया जाता है, तो कंपाइलर को यह नहीं पता होता है कि किस फ़ंक्शन को निष्पादित किया जाना चाहिए। वर्चुअल फ़ंक्शन कॉल को हल करने के लिए, कंपाइलर प्रत्येक फ़ंक्शन के लिए वर्चुअल फ़ंक्शन तालिका ( vtable ) का संकलन करता है जो वर्चुअल फ़ंक्शन की घोषणा करता है। इन वर्चुअल फ़ंक्शंस के लिए Vtable में ऑफ़सेट शामिल हैं। जब, रनटाइम पर, एक क्लास ऑब्जेक्ट बनाया जाता है, तो उसे क्लास के वीटेबल को पॉइंटर सौंपा जाता है। क्योंकि यह पॉइंटर उस प्रक्रिया के डेटा सेगमेंट में है जो ऑब्जेक्ट बनाता है, फिर भले ही ऑब्जेक्ट को साझा मेमोरी सेगमेंट में बनाया गया हो, लेकिन पॉइंटर से Vtable तक का ऑब्जेक्ट केवल उस प्रक्रिया के लिए उपलब्ध होगा जिसने ऑब्जेक्ट बनाया था। इसका मतलब है कि अन्य प्रक्रियाएं जो साझा किए गए ऑब्जेक्ट के वर्चुअल फ़ंक्शन को आमंत्रित करने का प्रयास करेंगी, विफल हो जाएंगी। प्रक्रियाओं के बीच वस्तुओं को साझा करने के लिए गतिशील लिंकिंग के विकल्पों पर विचार करने का यह मुख्य कारण है।
साझा मेमोरी में बनाए गए C ++ में ऑब्जेक्ट्स के पॉइंटर्स अलग-अलग प्रोसेस में उपलब्ध होंगे, अगर वे एक ही वर्चुअल एड्रेस के साथ शेयर्ड मेमोरी सेगमेंट को जोड़ते हैं, जिसे OS गारंटी नहीं दे सकता (OS वर्चुअल एड्रेस की पेशकश कर सकता है और इस प्रोसेस को एसोसिएट कर सकता है केवल तभी पता, जब वह पता उपयोग में न हो)। इसका समाधान आभासी पतों के लिए ऑफ़सेट का उपयोग करना है, जो किसी ऑब्जेक्ट को पॉइंटर बनाते समय, आधार वर्चुअल एड्रेस में जोड़ा जाता है। इसी तरह, C ++ में पॉइंटर्स के बजाय, हमारे पास ऑफ़सेट होना चाहिए।
कंपाइलर प्रक्रिया डेटा के मानक खंड में वर्ग के स्थिर डेटा सदस्यों को आवंटित करता है, अर्थात, विभिन्न प्रक्रियाओं में इन सदस्यों की अलग-अलग प्रतियां होंगी। इस प्रकार, यदि इन स्थिर डेटा सदस्यों की एक प्रति की आवश्यकता है, तो उन्हें ऑफसेट द्वारा अंतर्निहित वर्चुअल पते (जिसे साझा की गई मेमोरी में मैप किया जाता है) से प्रतिस्थापित किया जाना चाहिए।
एक साझा वस्तु की विभिन्न प्रक्रियाओं द्वारा एक साथ उपयोग से डेटा भ्रष्टाचार हो सकता है। पारस्परिक बहिष्कार सुनिश्चित करने के लिए, IPC ( अंतर-प्रक्रिया संचार ) तंत्र का उपयोग किया जाना चाहिए

डायनामिक लिंकिंग का सबसे अधिक इस्तेमाल किया जाने वाला वैकल्पिक रूप से रिकरिंग टेम्पलेट टेम्पलेट पैटर्न ( CRTP ) है। CRTP का उपयोग स्थैतिक बहुरूपता को लागू करने के लिए किया जाता है। स्टेटिक बहुरूपता यह प्रभाव आभासी कार्यों के लिए धन्यवाद प्राप्त करता है, जिससे आपको रन टाइम के बजाय संकलित समय में व्युत्पन्न वर्गों में अतिभारित तरीकों का चयन करने की अनुमति मिलती है। CRTP का उपयोग करते हुए, व्युत्पन्न वर्ग बेस टेम्पलेट वर्ग को विरासत में देता है, जो व्युत्पन्न वर्ग इंटरफ़ेस को लागू करता है। एक व्युत्पन्न वर्ग के उदाहरणों को ठीक से हटाने के लिए, बेस को डिलेटर वर्ग विरासत में मिला है, जो एक आभासी विध्वंसक को परिभाषित करता है। एक आभासी विध्वंसक बेस क्लास के लिए एक पॉइंटर के माध्यम से व्युत्पन्न वर्गों की वस्तुओं को प्रदान करता है।

class Deletor { public: virtual ~Deletor() {} }; template<typename T> class Base: public Deletor { public: int Run() { return static_cast<T*>(this)->DoIt(); } }; class Derived1: public Base<Derived1> { public: int DoIt() { /* implementation for Derived1 */ } }; class Derived2 : public Base<Derived2> { public: int DoIt() { /* implementation for Derived2 */ } }; int main() { Derived1 Obj1; Derived2 Obj2; Obj1.Run(); /* runs DoIt() implementation */ Obj2.Run(); /* runs DoIt() implementation */ };

डेलेटोर के आधार वर्ग का उपयोग किए बिना, जैसा कि ऊपर दिए गए उदाहरण में है, व्युत्पन्न वर्गों को विषम (उदाहरण के लिए, एक कंटेनर में) संग्रहीत नहीं किया जा सकता है, क्योंकि सीआरटीपी का प्रत्येक आधार वर्ग एक अद्वितीय प्रकार है। बेस और बेस संबंधित वर्ग नहीं हैं, इसलिए, भले ही इन ऑब्जेक्ट्स को बेसडिलेटर / ऑब्जेक्ट्स के कंटेनर में विषम रूप से संग्रहीत किया जा सकता है, यह पुनरावृत्तियों (कॉलिंग, उदाहरण के लिए, DoIt () विधि, उदाहरण के रूप में) का उपयोग करके बहुरूपता प्रदान करना संभव नहीं होगा। CRTP उन अनुप्रयोगों के लिए उपयुक्त है जहां ग्राहकों को केवल एक प्रकार का व्युत्पन्न वर्ग बनाना होगा।

नकली इंटरफ़ेस (डिज़ाइन पैटर्न)

यहां प्रस्तुत प्रतिरूप स्थिर सदस्य कार्यों के टेम्पलेट का उपयोग करता है, न कि टेम्पलेट कक्षाओं का। इस पैटर्न के लिए आधार वर्ग के निर्माण की आवश्यकता होती है जो स्थिर कार्यों के पैटर्न को परिभाषित करता है जिसमें व्युत्पन्न वर्गों के इंटरफ़ेस कार्यों तक पहुंच होगी। लक्ष्य कंटेनर में व्युत्पन्न वर्गों की वस्तुओं को जोड़ना है, और फिर, कंटेनर गुजरने पर, आप ऑब्जेक्ट के प्रकार के बारे में कुछ भी जानने के बिना इंटरफ़ेस फ़ंक्शन को कॉल कर सकते हैं।

मान लीजिए कि हमें एक गतिशील रूप से जुड़े int siRun(int&) विधि के साथ एक श्रेणी पदानुक्रम की आवश्यकता है। हम स्थैतिक टेम्पलेट फ़ंक्शन Run_T और वर्चुअल डिस्ट्रक्टर के साथ एक बेस क्लास Run_T ।

Run_T(...) में एक ही रिटर्न प्रकार और siRun(..) के समान इनपुट पैरामीटर हैं, साथ ही शुरुआत में एक अतिरिक्त पैरामीटर, जो उस ऑब्जेक्ट के लिए एक पॉइंटर है जिसके साथ स्थिर टेम्पलेट फ़ंक्शन काम करता है। इस प्रकार, हम एक निजी चर *m_pfnRun_T घोषित करते हैं, जो एक फ़ंक्शन के लिए एक पॉइंटर है, एक निर्माता जो इस पॉइंटर को शून्य पर शुरू करता है, एक टेम्पलेट फ़ंक्शन ( Init ) को सूचक के मूल्य को स्थैतिक फ़ंक्शन (

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

के सही कार्यान्वयन

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

&Run_T) (siRun ) . class RunnableInterface { private: int (m_pfnRun_T)(void const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , m_pfnRun_T . void const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::> { private: template<RC::> struct helper; template<typename T> static char check(helper<&T::FNNAME>); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void const pObj, int &k) { static_cast<T>(pObj)->siRun(k); } typedef void (PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::)(int&)); char pBaseOffset = (char)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char const pBaseOffset = (char)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::> { private: template<RC::> struct helper; template<typename T> static char check(helper<&T::FNNAME>); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (PFN_RUN_T)(void* const); typedef void (PFN_RESET_T)(void const, int&); typedef void (PFN_SAYHELLO_T)(void const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T>(pObj)->siRun(); } template <typename T> static void Reset_T(void const pObj, int &k) { static_cast<T>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void const pObj) { static_cast<T>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::)()); CheckMemberFunction(siReset, void (T::)(int&)); CheckMemberFunction(siSayHello, void (T::)()); char pBaseOffset = (char)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char pBaseOffset = (char)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char pBaseOffset = (char)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char pBaseOffset = (char)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void const pObj) { return static_cast<T>(pObj)->siRun(); } template <typename T> static void Reset_T(void const pObj, int &k) { static_cast<T>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void const pObj) { static_cast<T>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::)()); CheckMemberFunction(siReset, void (T::)(int&)); CheckMemberFunction(siSayHello, void (T::)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base pObj1; DerivedOnce pObj2; DerivedTwice pObj3; char pBuf1 = (char)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface objects in a list. std::list<TestInterface> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

&Run_T) (siRun ) . class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , *m_pfnRun_T . void* const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface* ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .
&Run_T) (siRun ) . class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , *m_pfnRun_T . void* const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface* ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .
&Run_T) (siRun ) . class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , *m_pfnRun_T . void* const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface* ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

&Run_T) (siRun ) . class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , *m_pfnRun_T . void* const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface* ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .
&Run_T) (siRun ) . class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , *m_pfnRun_T . void* const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface* ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

 &Run_T)    (siRun )        . 
 class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; 
 ,  *m_pfnRun_T        . void* const pObj ,     RunnableInterface ,     . 
 
    ,  ,  ""      (, siRun() ),   static_cast           ,   , ,       .  ,    SFINAE ( substitution failure is not an error ),     ,     ,     ;  CreateMemberFunctionChecked  ,     ""   ,  ,   , ,        .   CheckMemberFunction     Init() ,        .  FNNAME       ;    CheckMemberFunction    ,    . 
 // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } 
   ,  RunnableInterface : 
 class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } }; 
        ,   int siRun(int &k) . ,         -  Init();   int Derived::siRun(int &k)        ( Run_T ),   : 
 class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; 
 friend class RunnableInterface;       ,     RunnableInterface       private  protected . 
         TestInterface*       (      CRTP),    : 
 int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } 
      -      RunnableInterface ?  ,             - ,      .        ,               . ,   ,       ,    .  Windows, GetModuleHandle()   ,      .               .  ,  Windows     : 
 class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 
  
     1, 2  3   ,    :     . 
     Qt Creator 5.0.2  MinGW 4.7 x86    Windows XP  Windows 7 x64. 
  
 
  testiface.h ( 1)   TestInterface,    : 
 int siRun(); void siReset(int &k); void siSayHello(); 
  1 - testiface.h 
 #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H 
 testclasses.h   2      Base ( TestInterface ), DerivedOnce ( Base )  DerivedTwice ( DerivedOnce ).        TestInterface::Init(),   -  .  ,     ,    TestInterface() .      TestInterface      siRun, siReset, siSayHello ,     private/protected . 
 
  2 - testclasses.h 
 #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H 
  main.cpp   3   WinAPI  : 
   Base, DerivedOnce, DerivedTwice      (owner)         (client) 
   ,               TestInterface* ,     siRun, siReset, siSayHello .         ;  "OWNER" (    ,   )     ;       ; "CLIENT"               (   ,  .. ),        ,              . 
 
      ,  DerivedTwice::siSayHello() ,     .      (-  CheckMemberFunction(siSayHello, void (T::*)())  TestInterface::Init()): 
 Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value 
    siSayHello  DerivedTwice ,  -  (, double d ),    .     (-  TestInterface::Init()   DerivedTwice ): 
 In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 
  3 - main.cpp 
 #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } 
    
 ,    ,  ,                .          .               .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

, , , . . .

&Run_T) (siRun ) . class RunnableInterface { private: int (m_pfnRun_T)(void const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} }; , m_pfnRun_T . void const pObj , RunnableInterface , . , , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , . // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::> { private: template<RC::> struct helper; template<typename T> static char check(helper<&T::FNNAME>); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } , RunnableInterface : class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (m_pfnRun_T)(this, k); } }; , int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), : class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } }; friend class RunnableInterface; , RunnableInterface private protected . TestInterface ( CRTP), : int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; } - RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows : class TestInterface { private: template <typename T> static int Run_T(void const pObj, int &k) { static_cast<T>(pObj)->siRun(k); } typedef void (PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::)(int&)); char pBaseOffset = (char)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char const pBaseOffset = (char)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (pfnRun_T)(this, k); } virtual ~TestInterface() {} }; 1, 2 3 , : . Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64. testiface.h ( 1) TestInterface, : int siRun(); void siReset(int &k); void siSayHello(); 1 - testiface.h #ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::> { private: template<RC::> struct helper; template<typename T> static char check(helper<&T::FNNAME>); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (PFN_RUN_T)(void* const); typedef void (PFN_RESET_T)(void const, int&); typedef void (PFN_SAYHELLO_T)(void const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T>(pObj)->siRun(); } template <typename T> static void Reset_T(void const pObj, int &k) { static_cast<T>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void const pObj) { static_cast<T>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::)()); CheckMemberFunction(siReset, void (T::)(int&)); CheckMemberFunction(siSayHello, void (T::)()); char pBaseOffset = (char)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char pBaseOffset = (char)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char pBaseOffset = (char)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char pBaseOffset = (char)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void const pObj) { return static_cast<T>(pObj)->siRun(); } template <typename T> static void Reset_T(void const pObj, int &k) { static_cast<T>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void const pObj) { static_cast<T>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::)()); CheckMemberFunction(siReset, void (T::)(int&)); CheckMemberFunction(siSayHello, void (T::)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected . 2 - testclasses.h #ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H main.cpp 3 WinAPI : Base, DerivedOnce, DerivedTwice (owner) (client) , TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , . , DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::)()) TestInterface::Init()): Assertion failed! Expression: has_member_siSayHello<void (T::)()>::value siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ): In instantiation of 'static void TestInterface::SayHello_T(void) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice] 3 - main.cpp #include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base pObj1; DerivedOnce pObj2; DerivedTwice pObj3; char pBuf1 = (char)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface objects in a list. std::list<TestInterface> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; } , , , . . .

&Run_T) (siRun ) .
class RunnableInterface { private: int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k) { return static_cast<T*>(pObj)->siRun( k ); } protected: template<typename T> void Init() { m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} int siRun(int &k) { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this, k); } virtual ~RunnableInterface() {} };
, *m_pfnRun_T . void* const pObj , RunnableInterface , .

, , "" (, siRun() ), static_cast , , , . , SFINAE ( substitution failure is not an error ), , , ; CreateMemberFunctionChecked , "" , , , , . CheckMemberFunction Init() , . FNNAME ; CheckMemberFunction , .
// Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } // This corresponding macro is used to check the existence of the // interface function in the derived class. #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); }
, RunnableInterface :
class RunnableInterface { private: CreateMemberFunctionChecker(siRun); int (*m_pfnRun_T)(void* const, int&); template<typename T> static int Run_T(void* const pObj, int &k ) { return static_cast<T*>(pObj)->siRun(k); } protected: template<typename T> void Init() { CheckMemberFunction(siRun, int (T::*)(int&)); m_pfnRun_T = &Run_T<T>; } public: RunnableInterface(): m_pfnRun_T(0) {} virtual ~RunnableInterface() {} int siRun(int &k) { assert(m_pfnRun_T); return (*m_pfnRun_T)(this, k); } };
, int siRun(int &k) . , - Init(); int Derived::siRun(int &k) ( Run_T ), :
class Test: public RunnableInterface { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*2; return 0; } protected: int m_value; public: Test(int value): m_value(value) { RunnableInterface::Init<Test>(); } }; class AdjustmentTest: public Test { friend class RunnableInterface; private: int siRun(int &k) { k = m_value*3; return 0; } public: AdjustmentTest(int value): Test(value) { RunnableInterface::Init<AdjustmentTest>(); } };
friend class RunnableInterface; , RunnableInterface private protected .
TestInterface* ( CRTP), :
int main() { RunnableInterface* const pObj1 = new Test(1); RunnableInterface* const pObj2 = new AdjustmentTest(4); std::list<RunnableInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); std::list<RunnableInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++ ) { RunnableInterface* const p = *i; int k; const int j = p->siRun(k); std::cout << "RUN: " << j << ":" << k << std::endl << std::endl; delete p; } return 0; }
- RunnableInterface ? , - , . , . , , , . Windows, GetModuleHandle() , . . , Windows :
class TestInterface { private: template <typename T> static int Run_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siRun(k); } typedef void (*PFN_RUN_T)(void* const, int&); CreateMemberFunctionChecker(siRun); // Offset to static template member functions. unsigned long m_ulRun_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, void (T::*)(int&)); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0) {} void siRun(int &k) { assert(m_ulRun_T_Offset); // Make sure Init() was called. char* const pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); (*pfnRun_T)(this, k); } virtual ~TestInterface() {} };

1, 2 3 , : .
Qt Creator 5.0.2 MinGW 4.7 x86 Windows XP Windows 7 x64.


testiface.h ( 1) TestInterface, :
int siRun(); void siReset(int &k); void siSayHello();
1 - testiface.h
#ifndef TESTIFACE_H #define TESTIFACE_H #include <windows.h> // for GetModuleHandle() // Using the SFINAE (Substitution Failure Is Not An Error) technique, // the following macro creates a template class with typename T and a // static boolean member "value" that is set to true if the specified // member function exists in the T class. // This macro was created based on information that was retrieved from // the following URLs: // https://groups.google.com/forum/?fromgroups#!topic/comp.lang.c++/DAq3H8Ph_1k // http://objectmix.com/c/779528-call-member-function-only-if-exists-vc-9-a.html #define CreateMemberFunctionChecker(FNNAME) template<typename T> struct has_member_##FNNAME; template<typename R, typename C> class has_member_##FNNAME<RC::*> { private: template<RC::*> struct helper; template<typename T> static char check(helper<&T::FNNAME>*); template<typename T> static char (& check(...))[2]; public: static const bool value = (sizeof(check<C>(0)) == sizeof(char)); } #define CheckMemberFunction(FNNAME, FNPROTOTYPE) { assert(has_member_##FNNAME<FNPROTOTYPE>::value); } typedef int (*PFN_RUN_T)(void* const); typedef void (*PFN_RESET_T)(void* const, int&); typedef void (*PFN_SAYHELLO_T)(void* const); #ifndef SINGLE_PROCESS class TestInterface { private: // Implement template functions. template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); // Offsets to static template member functions. unsigned long m_ulRun_T_Offset, m_ulReset_T_Offset, m_ulSayHello_T_Offset; protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); char *pBaseOffset = (char*)GetModuleHandle(NULL); m_ulRun_T_Offset = (unsigned long)&Run_T<T> - (unsigned long)pBaseOffset; m_ulReset_T_Offset = (unsigned long)&Reset_T<T> - (unsigned long)pBaseOffset; m_ulSayHello_T_Offset = (unsigned long)&SayHello_T<T> - (unsigned long)pBaseOffset; } public: TestInterface(): m_ulRun_T_Offset(0), m_ulReset_T_Offset(0), m_ulSayHello_T_Offset(0) {} int siRun() { assert(m_ulRun_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RUN_T pfnRun_T = (PFN_RUN_T)(pBaseOffset + m_ulRun_T_Offset); return (*pfnRun_T)(this); } void siReset(int &k) { assert(m_ulReset_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_RESET_T pfnReset_T = (PFN_RESET_T)(pBaseOffset + m_ulReset_T_Offset); (*pfnReset_T)(this, k); } void siSayHello() { assert(m_ulSayHello_T_Offset); // Make sure Init() was called. char *pBaseOffset = (char*)GetModuleHandle(NULL); PFN_SAYHELLO_T pfnSayHello_T = (PFN_SAYHELLO_T)(pBaseOffset + m_ulSayHello_T_Offset); (*pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #else class TestInterface { private: template <typename T> static int Run_T(void* const pObj) { return static_cast<T*>(pObj)->siRun(); } template <typename T> static void Reset_T(void* const pObj, int &k) { static_cast<T*>(pObj)->siReset(k); } template <typename T> static void SayHello_T(void* const pObj) { static_cast<T*>(pObj)->siSayHello(); } // Pointers to static template member functions. PFN_RUN_T m_pfnRun_T; PFN_RESET_T m_pfnReset_T; PFN_SAYHELLO_T m_pfnSayHello_T; CreateMemberFunctionChecker(siRun); CreateMemberFunctionChecker(siReset); CreateMemberFunctionChecker(siSayHello); protected: template <typename T> void Init() { CheckMemberFunction(siRun, int (T::*)()); CheckMemberFunction(siReset, void (T::*)(int&)); CheckMemberFunction(siSayHello, void (T::*)()); m_pfnRun_T = &Run_T<T>; m_pfnReset_T = &Reset_T<T>; m_pfnSayHello_T = &SayHello_T<T>; } public: TestInterface(): m_pfnRun_T(0), m_pfnReset_T(0), m_pfnSayHello_T(0) {} int siRun() { assert(m_pfnRun_T); // Make sure Init() was called. return (*m_pfnRun_T)(this); } void siReset(int &k) { assert(m_pfnReset_T); // Make sure Init() was called. (*m_pfnReset_T)(this, k); } void siSayHello() { assert(m_pfnSayHello_T); // Make sure Init() was called. (*m_pfnSayHello_T)(this); } virtual ~TestInterface() {} }; #endif // SINGLE_PROCESS #endif // TESTIFACE_H
testclasses.h 2 Base ( TestInterface ), DerivedOnce ( Base ) DerivedTwice ( DerivedOnce ). TestInterface::Init(), - . , , TestInterface() . TestInterface siRun, siReset, siSayHello , private/protected .

2 - testclasses.h
#ifndef TESTCLASSES_H #define TESTCLASSES_H #ifndef TESTIFACE_H #include "testiface.h" #endif class Base: public TestInterface { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*10; } void siSayHello() { std::cout << "Hello from Base" << std::endl; } protected: int m_value; public: Base(int value = 1): m_value(value) { TestInterface::Init<Base>(); } }; class DerivedOnce: public Base { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*100; } void siSayHello() { std::cout << "Hello from DerivedOnce" << std::endl; } public: DerivedOnce(): Base() { TestInterface::Init<DerivedOnce>(); ++m_value; } }; class DerivedTwice: public DerivedOnce { friend class TestInterface; private: int siRun() { return m_value; } void siReset(int &k) { k = m_value*1000; } void siSayHello() { std::cout << "Hello from DerivedTwice" << std::endl; } public: DerivedTwice(): DerivedOnce() { TestInterface::Init<DerivedTwice>(); ++m_value; } }; #endif // TESTCLASSES_H
main.cpp 3 WinAPI :
Base, DerivedOnce, DerivedTwice (owner) (client)
, TestInterface* , siRun, siReset, siSayHello . ; "OWNER" ( , ) ; ; "CLIENT" ( , .. ), , .

, DerivedTwice::siSayHello() , . (- CheckMemberFunction(siSayHello, void (T::*)()) TestInterface::Init()):
Assertion failed! Expression: has_member_siSayHello<void (T::*)()>::value
siSayHello DerivedTwice , - (, double d ), . (- TestInterface::Init() DerivedTwice ):
In instantiation of 'static void TestInterface::SayHello_T(void*) [with T = DerivedTwide]'; Required from 'void TestInterface::Init [with T = DerivedTwice]
3 - main.cpp
#include <windows.h> #include <stdio.h> #include <tchar.h> #include <list> #include <iostream> #include <conio.h> #include <assert.h> #include "testclasses.h" int main() { const SIZE_T BufSize = 1024; const TCHAR szName[] = TEXT("Local\\SharedMemBlockObject"); const HANDLE hMapFile = CreateFileMapping( INVALID_HANDLE_VALUE, // use paging file NULL, // default security PAGE_READWRITE, // read/write access 0, // maximum object size (high-order DWORD) BufSize, // maximum object size (low-order DWORD) szName ); // name of mapping object if (hMapFile == NULL) { std::cout << "Could not create file mapping object (" << GetLastError() << ").\n" << std::endl; return 1; } const bool fFirstProcess = (GetLastError() != ERROR_ALREADY_EXISTS); // Map the file to this process' address space. const LPCTSTR pBuf = (LPTSTR) MapViewOfFile( hMapFile, // handle to map object FILE_MAP_ALL_ACCESS, // read/write permission 0, 0, BufSize ); if (pBuf == NULL) { std::cout << "Could not map view of file (" << GetLastError() << ").\n" << std::endl; CloseHandle( hMapFile ); return 1; } Base *pObj1; DerivedOnce *pObj2; DerivedTwice *pObj3; char *pBuf1 = (char*)pBuf; if (fFirstProcess) { std::cout << "OWNER PROCESS: " << std::endl; // Create TestInterface objects in shared memory. pObj1 = new(pBuf1)Base; // first available memory addr pBuf1 += sizeof(Base); // skip to next available memory addr pObj2 = new(pBuf1)DerivedOnce; pBuf1 += sizeof(DerivedOnce); // skip to next available memory addr pObj3 = new(pBuf1)DerivedTwice; } else { std::cout << "CLIENT PROCESS: " << std::endl; // Access objects that are in shared memory. pObj1 = (Base*)pBuf1; // addr where Base obj was created pBuf1 += sizeof(Base); pObj2 = (DerivedOnce*)pBuf1; // addr where DerivedOnce obj was created pBuf1 += sizeof(DerivedOnce); pObj3 = (DerivedTwice*)pBuf1; // addr where DerivedTwice obj was created } char szHexBuf[12]; sprintf(szHexBuf, "0x%lx", (unsigned long) pBuf); std::cout << "pBuf: " << szHexBuf << std::endl << std::endl; // Place TestInterface* objects in a list. std::list<TestInterface*> list1; list1.insert(list1.end(), pObj1); list1.insert(list1.end(), pObj2); list1.insert(list1.end(), pObj3); // Let TestInterface objects greet, run and reset generically. std::list<TestInterface*>::iterator i; for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; p->siSayHello(); std::cout << "RUN: " << p->siRun() << std::endl; int kk; p->siReset( kk ); std::cout << "RESET: " << kk << std::endl << std::endl; } std::cout << "Press any key to end program" << std::endl; if (fFirstProcess) std::cout << " and destroy objects in shared memory" << std::endl; std::cout << "..." << std::endl; while (!kbhit()) Sleep(100); if (fFirstProcess) { // Objects are no longer needed, call destructors. for (i = list1.begin(); i != list1.end(); i++) { TestInterface* const p = *i; // We need to call the destructor explicitly because // the new with placement operator was used. // We cannot call "delete p;" p->~TestInterface(); } } UnmapViewOfFile(pBuf); CloseHandle(hMapFile); return 0; }

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