Create_Semaphore.cpp
上传用户:dq031136
上传日期:2022-08-08
资源大小:802k
文件大小:3k
- #include <genstub.cpp>
- // This is a child thread procedure that waits for a semaphore,
- // holds the semaphore for five seconds, and releases the semaphore.
- // Threads that cannot get semaphores will wait until other threads exit.
- DWORD WINAPI ChildThreadProc( HWND hWnd )
- {
- TCHAR szBuffer[256]; // buffer
- DWORD dwSemCount = 0; // printing semaphore count
- HANDLE hSemaphore = OpenSemaphore( SYNCHRONIZE, FALSE, "TEST_SEMAPHORE" );
- wsprintf( szBuffer,"Thread %x waiting for semaphore %x",
- GetCurrentThreadId( ), hSemaphore );
- SendMessage( hWnd, WM_USER, 0, (LPARAM) szBuffer );
- // Check for signaled semaphore.
- WaitForSingleObject( hSemaphore, INFINITE );
- wsprintf( szBuffer,"Thread %x got semaphore", GetCurrentThreadId( ) );
- SendMessage( hWnd, WM_USER, 0, (LPARAM) szBuffer );
- Sleep( 5000 );
- // Release semaphore.
- ReleaseSemaphore( hSemaphore, 1, &dwSemCount );
- wsprintf( szBuffer,"Thread %x is done with semaphore. Its count was %ld.",
- GetCurrentThreadId( ), dwSemCount );
- SendMessage( hWnd, WM_USER, 0, (LPARAM) szBuffer );
- CloseHandle( hSemaphore );
- ExitThread( TRUE );
- }
- // Windows message procedure.
- LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
- {
- static HANDLE hSemaphore = 0;
- switch (uMsg)
- {
- case WM_CREATE:
- hSemaphore = CreateSemaphore( NULL, 4, 4, "TEST_SEMAPHORE" );
- return DefWindowProc( hWnd, uMsg, wParam, lParam );
- case WM_COMMAND: // process menu items
- switch ( LOWORD( wParam ) )
- {
- case IDM_TEST: // start up a thread.
- {
- DWORD dwChildId;
- CreateThread( NULL, 0, ChildThreadProc, hWnd, 0, &dwChildId );
- }
- break;
- case IDM_EXIT:
- DestroyWindow( hWnd );
- break;
- }
- break;
- case WM_USER:
- { // Message to show synchronization actions.
- TCHAR szBuffer[101];
- static int row = 0;
- static int msg_num = 1;
- HDC hDC = GetDC( hWnd );
- FillMemory( szBuffer, 100, 32 );
- TextOut( hDC, 0, row, szBuffer, 100 );
- wsprintf( szBuffer, "%3d: %s", msg_num++, (LPTSTR)lParam );
- TextOut( hDC, 0, row, szBuffer, lstrlen( szBuffer ) );
- if ( row > 200 )
- row = 0;
- else
- row += 20;
- ReleaseDC( hWnd, hDC );
- }
- break;
- case WM_DESTROY:
- if ( hSemaphore )
- CloseHandle( hSemaphore );
- PostQuitMessage( 0 );
- break;
- default:
- return DefWindowProc( hWnd, uMsg, wParam, lParam );
- }
- return NULL;
- }