ファイルマッピング

プロセス間データ共有

HANDLE CreateFileMapping(
	HANDLE hFile ,
	LPSECURITY_ATTRIBUTES lpFileMappingAttributes ,
	DWORD flProtect ,
	DWORD dwMaximumSizeHigh , DWORD dwMaximumSizeLow ,
	LPCTSTR lpName
);

HANDLE OpenFileMapping(
	DWORD dwDesiredAccess,
	BOOL bInheritHandle,
	LPCTSTR lpName
);

LPVOID MapViewOfFile(
	HANDLE hFileMappingObject ,
	DWORD dwDesiredAccess ,
	DWORD dwFileOffsetHigh , DWORD dwFileOffsetLow,
	DWORD dwNumberOfBytesToMap
);

LPVOID MapViewOfFileEx(
	HANDLE hFileMappingObject,
	DWORD dwDesiredAccess,
	DWORD dwFileOffsetHigh , DWORD dwFileOffsetLow ,
	DWORD dwNumberOfBytesToMap,
	LPVOID lpBaseAddress
);

#include <windows.h>
#define MAP TEXT("KITTY_MAP")

PSTR strAllCmd;

LRESULT CALLBACK WndProc(HWND hWnd , UINT msg , WPARAM wp , LPARAM lp) {
	HDC hdc;
	PAINTSTRUCT ps;
	RECT rect;

	switch (msg) {
	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;
	case WM_PAINT:
		GetClientRect(hWnd , &rect);

		hdc = BeginPaint(hWnd , &ps);
		DrawText(hdc , strAllCmd , -1 , &rect , DT_LEFT | DT_WORDBREAK);
		EndPaint(hWnd , &ps);
		return 0;
	}
	return DefWindowProc(hWnd , msg , wp , lp);
}

int WINAPI WinMain(HINSTANCE hInstance , HINSTANCE hPrevInstance ,
			PSTR lpCmdLine , int nCmdShow) {
	HWND hWnd;
	MSG msg;
	WNDCLASS winc;
	TCHAR strLine[1024];
	HANDLE hMap = CreateFileMapping((HANDLE)0xFFFFFFFF , NULL ,
				PAGE_READWRITE , 0 , 1024 , MAP);

	strAllCmd = MapViewOfFile(hMap , FILE_MAP_WRITE , 0 , 0 , 0);
	if (lstrlen(strAllCmd)) 
		wsprintf(strAllCmd , TEXT("%s\n%s") , strAllCmd , lpCmdLine);
	else lstrcat(strAllCmd , lpCmdLine);

	winc.style 		= CS_HREDRAW | CS_VREDRAW;
	winc.lpfnWndProc	= WndProc;
	winc.cbClsExtra	= winc.cbWndExtra	= 0;
	winc.hInstance		= hInstance;
	winc.hIcon		= LoadIcon(NULL , IDI_APPLICATION);
	winc.hCursor		= LoadCursor(NULL , IDC_ARROW);
	winc.hbrBackground	= GetStockObject(WHITE_BRUSH);
	winc.lpszMenuName	= NULL;
	winc.lpszClassName	= TEXT("KITTY");

	if (!RegisterClass(&winc)) return 1;

	hWnd = CreateWindow(
			TEXT("KITTY") , TEXT("Kitty on your lap") ,
			WS_OVERLAPPEDWINDOW | WS_VISIBLE ,
			CW_USEDEFAULT , CW_USEDEFAULT ,
			CW_USEDEFAULT , CW_USEDEFAULT ,
			NULL , NULL , hInstance , NULL
	);

	if (hWnd == NULL) return 1;

	while (GetMessage(&msg , NULL , 0 , 0 )) {
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	UnmapViewOfFile(strAllCmd);
	CloseHandle(hMap);
	return msg.wParam;
}

/*test.h*/
#ifdef __cplucplus
#define DLL_EXPORT extern "C" __declspec (dllexport)
#else 
#define DLL_EXPORT __declspec (dllexport)
#endif

DLL_EXPORT DWORD CALLBACK GetDllUsers();

/*dll_test.c*/
#include <windows.h>
#include "test.h"

#define MAP TEXT("KITTY_MAP")
DWORD * pdwUsers;

int WINAPI DllEntryPoint(HINSTANCE hInstance , DWORD fdwReason , PVOID pvReserved) {
	static HANDLE hMap;

	switch(fdwReason) {
	case DLL_PROCESS_ATTACH:
		hMap = CreateFileMapping((HANDLE)0xFFFFFFFF , NULL ,
				PAGE_READWRITE , 0 , sizeof (DWORD) , MAP);
		pdwUsers = (DWORD *)MapViewOfFile(
				hMap , FILE_MAP_WRITE , 0 , 0 , 0);
		*pdwUsers += 1;
		break;
	case DLL_PROCESS_DETACH:
		*pdwUsers += -1;
		UnmapViewOfFile(pdwUsers);
		CloseHandle(hMap);
	}
	return TRUE;
}

DLL_EXPORT DWORD CALLBACK GetDllUsers() {
	return *pdwUsers;
}

#include <windows.h>
#include "test.h"

LRESULT CALLBACK WndProc(HWND hWnd , UINT msg , WPARAM wp , LPARAM lp) {
	HDC hdc;
	PAINTSTRUCT ps;
	TCHAR str[128];

	switch (msg) {
	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;
	case WM_PAINT:
		hdc = BeginPaint(hWnd , &ps);
		wsprintf(str ,
			TEXT("DLL を使用しているプロセス = %d") , GetDllUsers());
		TextOut(hdc , 0 , 0 , str , lstrlen(str));
		EndPaint(hWnd , &ps);
	}
	return DefWindowProc(hWnd , msg , wp , lp);
}

int WINAPI WinMain(HINSTANCE hInstance , HINSTANCE hPrevInstance ,
			PSTR lpCmdLine , int nCmdShow) {
	HWND hWnd;
	MSG msg;
	WNDCLASS winc;

	winc.style 		= CS_HREDRAW | CS_VREDRAW;
	winc.lpfnWndProc	= WndProc;
	winc.cbClsExtra	= winc.cbWndExtra	= 0;
	winc.hInstance		= hInstance;
	winc.hIcon		= LoadIcon(NULL , IDI_APPLICATION);
	winc.hCursor		= LoadCursor(NULL , IDC_ARROW);
	winc.hbrBackground	= GetStockObject(WHITE_BRUSH);
	winc.lpszMenuName	= NULL;
	winc.lpszClassName	= TEXT("KITTY");

	if (!RegisterClass(&winc)) return 1;

	hWnd = CreateWindow(
			TEXT("KITTY") , TEXT("Kitty on your lap") ,
			WS_OVERLAPPEDWINDOW | WS_VISIBLE ,
			CW_USEDEFAULT , CW_USEDEFAULT ,
			CW_USEDEFAULT , CW_USEDEFAULT ,
			NULL , NULL , hInstance , NULL
	);

	if (hWnd == NULL) return 1;

	while (GetMessage(&msg , NULL , 0 , 0 )) {
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return msg.wParam;
}

CreateFileMapping()

HANDLE CreateFileMapping(
	HANDLE hFile ,
	LPSECURITY_ATTRIBUTES lpFileMappingAttributes ,
	DWORD flProtect ,
	DWORD dwMaximumSizeHigh , DWORD dwMaximumSizeLow ,
	LPCTSTR lpName
);

OpenFileMapping()

HANDLE OpenFileMapping(
	DWORD dwDesiredAccess,
	BOOL bInheritHandle,
	LPCTSTR lpName
);

MapViewOfFile()

LPVOID MapViewOfFile(
	HANDLE hFileMappingObject ,
	DWORD dwDesiredAccess ,
	DWORD dwFileOffsetHigh , DWORD dwFileOffsetLow,
	DWORD dwNumberOfBytesToMap
);

MapViewOfFileEx()

LPVOID MapViewOfFileEx(
	HANDLE hFileMappingObject ,
	DWORD dwDesiredAccess ,
	DWORD dwFileOffsetHigh , DWORD dwFileOffsetLow,
	DWORD dwNumberOfBytesToMap ,
	LPVOID lpBaseAddress
);

UnmapViewOfFile()

FlushViewOfFile()