dll导出函数调用封装

来源：互联网发布：孙笑侠知乎编辑：程序博客网时间：2024/05/16 06:27

为了方便，备份

/********************************************************************
created: 2012:24:4 12:22:40
author: Insert
purpose: dll export functions encapsulation
*********************************************************************/
#ifndef __DLLEXPORT__H__F53BDD46_6C8D_4EB1_8E65_5ED75697F6B8__
#define __DLLEXPORT__H__F53BDD46_6C8D_4EB1_8E65_5ED75697F6B8__

#include <Windows.h>
#include <assert.h>

#include <Shlwapi.h>
#pragma comment(lib, "Shlwapi.lib")

#define __CALLINGCONVENTION __cdecl

typedef struct _SNAMEPFUNC
{
FARPROC* pFunc;
LPSTR lpName;
} _SNF;

#define EMETHOD(__ret, __name, __pd, __pr)\
private:\
__ret(__CALLINGCONVENTION *_fn##__name)__pd;\
public:\
inline static __ret __name __pd\
{\
assert(NULL != _Instance()->_fn##__name);\
return _Instance()->_fn##__name __pr;\
}

#define BEGIN_EFUNC_MAP {\
_SNF __snf[] ={

#define EFUNC(__name) {(FARPROC *)&_fn##__name, #__name},

#define END_EFUNC_MAP(__hm)\
};\
int __n = sizeof(__snf) / sizeof(_SNF);\
for(int i = 0; i < __n; i++)\
{\
*__snf[i].pFunc = ::GetProcAddress( __hm, __snf[i].lpName );\
assert(NULL != *__snf[i].pFunc && "Unknown export function!");\
}\
}

class CExportFucntions
{
//Interface of dll exports
EMETHOD(void, funnoparam, (), ());
EMETHOD(int, funwithparam, (int p1, bool p2), (p1, p2));
public:

private:
CExportFucntions() : _hmModule(NULL)
{
_Instance();
}
~CExportFucntions(){};

static CExportFucntions* _Instance()
{
static CExportFucntions __ef;
return &__ef;
}

const static TCHAR* _szModulePath;
HMODULE _hmModule;

BOOL _Initialize()
{
  TCHAR szDllPath[MAX_PATH] = {0};
  if (0 == ::GetModuleFileName(NULL, szDllPath, MAX_PATH))
  {
   assert(0 && "GetModuleFileName failed!");
   return FALSE;
  }
  if (FALSE == ::PathAppend(szDllPath, _szModulePath))
  {
   assert(0 && "GetModuleFileName failed!");
   return FALSE;
  }
  if (FALSE == ::PathFileExists(szDllPath))
  {
   assert(0 && "DLL is not exist!");
   return FALSE;
  }

  _hmModule = ::LoadLibrary(szDllPath);
  if (NULL == _hmModule)
  {
   assert(0 && "LoadLibrary failed!");
   return FALSE;
  }

  BEGIN_EFUNC_MAP
   EFUNC(funnoparam)
   EFUNC(funwithparam)
  END_EFUNC_MAP(_hmModule)

return TRUE;
}

void _UnInitialize()
{
  if (NULL != _hmModule)
  {
   ::FreeLibrary(_hmModule);
  }
}
};

const TCHAR* CExportFucntions::_szModulePath = TEXT("..\\somedll.dll");

#endif