互斥器的功能是，使多個線程和諧工作。同一時間內，只能有一個線程得到互斥對象，並獲得資源操作權限，那么如果同一時間其他線程也想去操作資源，此時就會因為Mutex未處於激發狀態，而無奈的等待…這時候，線程就會進入blocking（阻塞）狀態，直到Mutex讓出來。
總結下Mutex的操作步驟，分為以下幾個功能：
1. 產生一個全局互斥器Mutex（一個Mutex可以看做一個資源，如果要多個資源，則需要創建多個Mutex句柄）；
2. 鎖住互斥器Mutex：獲得一個Mutex的擁有權，其他線程只能等待。當需要鎖操作時，如果此時鎖未處於激活狀態，線程就得等待（也就是阻塞狀態/sleep）並每隔一段時間嘗試着再次去占用Mutex，不行就繼續阻塞直到Mutex被讓出；
3. 釋放互斥器Mutex，使得后一個等待的線程能夠擁有它並得以獲得資源；
這里需要說明的是，Mutex的擁有權並非屬於那個產生它的線程，而是最后那個獲得它且未釋放的線程。線程擁有了Mutex就好像線程進入了臨界區域一樣。一次只能有一個線程獲得Mutex。
和大部分核心對象一樣，Mutex是通過計數來實現互斥，當Mutex被占用時計數為1，當Mutex未被占用時計數降低為0；
但是，有些情況是殘酷的所以必須避免：在一個程序中，線程絕對不應該在即將結束時還擁有一個Mutex，否則該Mutex將無法被釋放。
Win32下Mutex相關接口：
1. 創建一個互斥器，該接口返回一個HANDLE：
HANDLE CreateMutex(LPSECURITY_ATTRIBUTES lpMutexAttributes, BOOL bInitialOwner, LPCTSTR lpName);
2. 打開一個互斥器，該互斥器已被創建過：
HANDLE OpenMutexW(DWORD dwDesiredAccess, BOOL bInheritHandle, LPCWSTR lpName);
3. 等待一個資源對象：
DWORD WaitForSingleObject(HANDLE hHandle, DWORD dwMilliseconds);
--hHandle:mutex句柄
--dwMilliseconds:INFINITE:表示無限等待，否則可以設置時間(ms)
4. 等待多個資源對象：
DWORD WaitForMultipleObjects(DWORD nCount, CONST HANDLE *lpHandles, BOOL bWaitAll, DWORD dwMilliseconds);
--nCount:句柄的數量
--*lpHandles:句柄數組
--bWaitAll:如果為TRUE則所有對象都空閑則獲得權限，如果為FALSE則只要有一個對象空閑就獲得權限
--dwMilliseconds:INFINITE:表示無限等待，否則可以設置時間(ms)
5. 等待多個資源對象，還可以等待消息：
DWORD MsgWaitForMultipleObjects(DWORD nCount, LPHANDLE pHandles, BOOL fWaitAll, DWORD dwMilliseconds, DWORD dwWakeMask);
6. 釋放互斥器
BOOL ReleaseMutex(HANDLE hMutex);
7. 摧毀互斥器
BOOL CloseHandle(HANDLE hObject);
哲學家就餐：
我們知道，哲學家就餐問題就是為了解決所有老頭都拿着一支筷子，但都在等待另外雙筷子進行吃飯的尷尬場面。
比如一共5個哲學家，但也只有5支筷子。如果大家同時抓起一根筷子，很快就進入死鎖場面；但如果不允許老頭子拿起一根筷子，而是只允許一次拿起一雙筷子，此時就可以保證至少2個老頭能夠先吃飯了，即使還留着一根筷子另外3個老頭也只能傻等——這樣就能避免大家都吃不到飯的問題
那么如何使用Mutex來對哲學家問題進行解決呢？
#include "stdafx.h" extern HWND hWndMain; extern int g_nChopstickUser[]; extern int g_nDinerState[]; extern HANDLE g_hChopstickMutex[]; extern HANDLE g_hPhilosThread[]; extern BOOL g_bWaitMultiple; extern BOOL g_bFastDining; /**** * 線程執行 **/ DWORD WINAPI DiningThread(LPVOID pVoid) { /**** * 哲學家編號 **/ int nPhilosopher = (int)pVoid; /**** * 左手筷子 **/ int nLeftChopstick = nPhilosopher; /**** * 右手筷子 **/ int nRightChopstick = nLeftChopstick + 1; if (nRightChopstick > PHILOSOPERS - 1) { nRightChopstick = 0; } /**** * 左右手資源句柄(只能從這2個資源里去拿) * 句柄不會產生副本,永遠指向全局 **/ HANDLE hChopstickMutex[2] = {0}; hChopstickMutex[0] = g_hChopstickMutex[nLeftChopstick]; hChopstickMutex[1] = g_hChopstickMutex[nRightChopstick]; /**** * 隨機時間等待 **/ srand((unsigned) time(NULL) + (nPhilosopher + 1)); /**** * 哲學家等待 **/ Sleep(DINING_DELAY); /**** * 筷子狀態:RESTING; WAITING; EATING **/ while(TRUE) { if (g_bWaitMultiple) { /** 2根一起拿 **/ g_nDinerState[nPhilosopher] = WAITING; SendMessage(hWndMain, WM_FORCE_REPAINT, NULL, NULL); WaitForMultipleObjects(2,hChopstickMutex, TRUE, INFINITE); g_nChopstickUser[nLeftChopstick] = nPhilosopher; g_nChopstickUser[nRightChopstick] = nPhilosopher; } else { /** 一根根拿 **/ g_nDinerState[nPhilosopher] = WAITING; SendMessage(hWndMain, WM_FORCE_REPAINT, NULL, NULL); WaitForSingleObject(hChopstickMutex[0], INFINITE); g_nChopstickUser[nLeftChopstick] = nPhilosopher; Sleep(DINING_DELAY); g_nDinerState[nPhilosopher] = WAITING; SendMessage(hWndMain, WM_FORCE_REPAINT, NULL, NULL); WaitForSingleObject(hChopstickMutex[1], INFINITE); g_nChopstickUser[nRightChopstick] = nPhilosopher; } /**** * 獲取資源,開始吃吃吃吃..... **/ g_nDinerState[nPhilosopher] = EATING; SendMessage(hWndMain, WM_FORCE_REPAINT, NULL, NULL); Sleep(DINING_DELAY); /**** * 吃完了? "尼瑪,放下那雙筷子....!" **/ g_nDinerState[nPhilosopher] = RESTING; g_nChopstickUser[nLeftChopstick] = UNUSED; g_nChopstickUser[nRightChopstick] = UNUSED; SendMessage(hWndMain, WM_FORCE_REPAINT, NULL, NULL); ReleaseMutex(hChopstickMutex[0]); ReleaseMutex(hChopstickMutex[1]); Sleep(DINING_DELAY); } return 0; } void Dining() { for (int i = 0; i < PHILOSOPERS; i++) { g_hPhilosThread[i] = CreateThread(NULL, 0, DiningThread, (LPVOID)i, NULL, NULL); } }
#pragma once #include "resource.h" #include <math.h> /**** * 哲學家的數量 **/ #define PHILOSOPERS 6 /**** * 每個弧度角 **/ #define ANGLE_PER_RADIAN 57.295779513082320876798154814105 /**** * 狀態 **/ #define UNUSED -1 #define RESTING 0 #define WAITING 1 #define EATING 2 /**** * MSG:強制重繪 **/ #define WM_FORCE_REPAINT WM_APP + 1 /**** * 哲學家等待時間 **/ #define DINING_DELAY g_bFastDining ? (rand() / 25) : ((rand() % 5 + 1) * 1000) /**** * 哲學家休息時間 **/ #define DINING_RESTING (rand() % 6 + 1) * 1000 /**** * 哲學家吃飯時間 **/ #define DINING_EATING (rand() % 5 + 1) * 1000 /**** * 框架渲染 **/ void RenderFrame(HDC hdc); /**** * 就餐 **/ void Dining();
// Philosoper Dining.cpp : Defines the entry point for the application. // #include "stdafx.h" #include "mtverify.h" #define MAX_LOADSTRING 100 /************************************************************************/ /* 全局變量 */ /************************************************************************/ HWND hWndMain; /* 窗口句柄 */ RECT rcWinExt = {0, 0, 200, 200}; /* 正方形窗口,長寬 == 200 */ int g_nXExt = 200; int g_nYExt = 200; int g_nRadiusTable = g_nXExt / 4; /* 桌子半徑 == 50,設計上讓桌子在窗口中心 */ POINT g_ptWinOrg = {g_nXExt / 2, g_nYExt / 2}; /* 設置坐標原點在窗口中心) */ int g_nChopstickUser[PHILOSOPERS]; /* 筷子使用者 */ int g_nDinerState[PHILOSOPERS]; /* 盤中餐狀態 */ HANDLE g_hChopstickMutex[PHILOSOPERS]; /* 筷子互斥器 */ HANDLE g_hPhilosThread[PHILOSOPERS]; /* 哲學家線程 */ BOOL g_bWaitMultiple = TRUE; /* 哲學家問題就必須同時等待 */ BOOL g_bFastDining = FALSE; /* 演示吃快點還是吃慢點 */ /************************************************************************/ // Global Variables: HINSTANCE hInst; // current instance TCHAR szTitle[MAX_LOADSTRING]; // The title bar text TCHAR szWindowClass[MAX_LOADSTRING]; // the main window class name // Forward declarations of functions included in this code module: ATOM MyRegisterClass(HINSTANCE hInstance); BOOL InitInstance(HINSTANCE, int); LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM); INT_PTR CALLBACK About(HWND, UINT, WPARAM, LPARAM); int APIENTRY _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { UNREFERENCED_PARAMETER(hPrevInstance); UNREFERENCED_PARAMETER(lpCmdLine); // TODO: Place code here. MSG msg; HACCEL hAccelTable; // Initialize global strings LoadString(hInstance, IDS_APP_TITLE, szTitle, MAX_LOADSTRING); LoadString(hInstance, IDC_PHILOSOPERDINING, szWindowClass, MAX_LOADSTRING); MyRegisterClass(hInstance); // Perform application initialization: if (!InitInstance (hInstance, nCmdShow)) { return FALSE; } hAccelTable = LoadAccelerators(hInstance, MAKEINTRESOURCE(IDC_PHILOSOPERDINING)); // Main message loop: while (GetMessage(&msg, NULL, 0, 0)) { if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg)) { TranslateMessage(&msg); DispatchMessage(&msg); } } return (int) msg.wParam; } // // FUNCTION: MyRegisterClass() // // PURPOSE: Registers the window class. // // COMMENTS: // // This function and its usage are only necessary if you want this code // to be compatible with Win32 systems prior to the 'RegisterClassEx' // function that was added to Windows 95. It is important to call this function // so that the application will get 'well formed' small icons associated // with it. // ATOM MyRegisterClass(HINSTANCE hInstance) { WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = hInstance; wcex.hIcon = LoadIcon(hInstance, MAKEINTRESOURCE(IDI_PHILOSOPERDINING)); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = MAKEINTRESOURCE(IDC_PHILOSOPERDINING); wcex.lpszClassName = szWindowClass; wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL)); return RegisterClassEx(&wcex); } // // FUNCTION: InitInstance(HINSTANCE, int) // // PURPOSE: Saves instance handle and creates main window // // COMMENTS: // // In this function, we save the instance handle in a global variable and // create and display the main program window. // BOOL InitInstance(HINSTANCE hInstance, int nCmdShow) { HWND hWnd; hInst = hInstance; // Store instance handle in our global variable /**** * 這里對話框做小點: **/ hWnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, 50, 5, 800, 600, NULL, NULL, hInstance, NULL); /**** * 坑爹,因為這里沒改導致所有畫面無法顯示 * 更新窗口句柄 */ hWndMain = hWnd ; if (!hWnd) { return FALSE; } /**** * 資源初始化 **/ for (int i = 0; i < PHILOSOPERS; i++) { g_nDinerState[i] = RESTING; /* 盤中餐一開始都是休息狀態的 */ g_nChopstickUser[i] = UNUSED; /* 筷子一開始都是未使用狀態的 */ g_hChopstickMutex[i] = CreateMutex(NULL, FALSE, NULL); /* 不指定用戶也無名 */ } ShowWindow(hWnd, nCmdShow); UpdateWindow(hWnd); /**** * 開始就餐 **/ Dining(); return TRUE; } void RenderFrame(HDC hdc) { RECT rcClient, rc ; HPEN hPenOld ; HFONT hFont, hFontOld ; int nRadius ; int nPos, nPosNext, x, y, nXPhilosopher, nYPhilosopher ; double dAngle, dRadian ; TCHAR szName[16] ; GetClientRect(hWndMain, &rcClient) ; SelectObject(hdc, GetStockObject(NULL_BRUSH)) ; SetMapMode(hdc, MM_ANISOTROPIC) ; SetWindowExtEx(hdc, g_nXExt, g_nYExt, NULL) ; SetWindowOrgEx(hdc, g_ptWinOrg.x, g_ptWinOrg.y, NULL) ; SetViewportExtEx(hdc, rcClient.right, rcClient.bottom, NULL) ; SetViewportOrgEx(hdc, rcClient.right / 2, rcClient.bottom / 2, NULL) ; hFont = CreateFont(5, 0, 0, 0, FW_HEAVY, FALSE, FALSE, FALSE, GB2312_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, DEFAULT_QUALITY, FIXED_PITCH | FF_SWISS, TEXT("楷體")) ; hFontOld = (HFONT) SelectObject(hdc, hFont) ; rc.left = g_ptWinOrg.x - 10 ; rc.top = g_ptWinOrg.y - 10 ; rc.right = g_ptWinOrg.x + 10 ; rc.bottom = g_ptWinOrg.y + 10 ; Ellipse(hdc, rc.left, rc.top, rc.right, rc.bottom) ; Ellipse(hdc, rc.left - 40, rc.top - 40, rc.right + 40, rc.bottom + 40) ; StringCchPrintf(szName, 16, TEXT("紅燒肉")) ; DrawText(hdc, szName, -1, &rc, DT_CENTER | DT_SINGLELINE | DT_VCENTER) ; dAngle = 360.0 / PHILOSOPERS ; for (nPos = 0 ; nPos < PHILOSOPERS ; nPos++) { dRadian = (nPos * dAngle) / ANGLE_PER_RADIAN; x = g_ptWinOrg.x + (int)(sin(dRadian) * g_nRadiusTable * 0.5) ; y = g_ptWinOrg.y - (int)(cos(dRadian) * g_nRadiusTable * 0.5) ; MoveToEx(hdc, x, y, NULL) ; x = g_ptWinOrg.x + (int)(sin(dRadian) * g_nRadiusTable * 0.9) ; y = g_ptWinOrg.y - (int)(cos(dRadian) * g_nRadiusTable * 0.9) ; LineTo(hdc, x, y) ; } for (nPos = 0 ; nPos < PHILOSOPERS ; nPos++) { nRadius = (int) (g_nRadiusTable * 0.2) ; dRadian = (nPos * dAngle + dAngle / 2) / ANGLE_PER_RADIAN ; x = g_ptWinOrg.x + (int)(sin(dRadian) * g_nRadiusTable * 0.6) ; y = g_ptWinOrg.y - (int)(cos(dRadian) * g_nRadiusTable * 0.6) ; rc.left = x - nRadius ; rc.top = y - nRadius ; rc.right = x + nRadius ; rc.bottom = y + nRadius ; switch (g_nDinerState[nPos]) { case RESTING: hPenOld = (HPEN) SelectObject(hdc, CreatePen(PS_SOLID, 1, 0x00FF00)) ; SetTextColor(hdc, 0x00FF00) ; StringCchPrintf(szName, 16, TEXT("休息")) ; break ; case WAITING: hPenOld = (HPEN) SelectObject(hdc, CreatePen(PS_SOLID, 1, 0x0000FF)) ; SetTextColor(hdc, 0x0000FF) ; StringCchPrintf(szName, 16, TEXT("想吃肉!")) ; break ; case EATING: hPenOld = (HPEN) SelectObject(hdc, CreatePen(PS_SOLID, 1, 0xE28C12)) ; SetTextColor(hdc, 0xE28C12) ; StringCchPrintf(szName, 16, TEXT("有肉吃!")) ; break ; } Ellipse(hdc, rc.left, rc.top, rc.right, rc.bottom) ; DrawTextEx(hdc, szName, -1, &rc, DT_CENTER | DT_SINGLELINE | DT_VCENTER, NULL) ; nRadius = (int)(g_nRadiusTable * 0.3) ; dRadian = (nPos * dAngle + dAngle / 2) / ANGLE_PER_RADIAN ; nXPhilosopher = g_ptWinOrg.x + (int)(sin(dRadian) * g_nRadiusTable * 1.4) ; nYPhilosopher = g_ptWinOrg.y - (int)(cos(dRadian) * g_nRadiusTable * 1.4) ; rc.left = nXPhilosopher - nRadius ; rc.top = nYPhilosopher - nRadius ; rc.right = nXPhilosopher + nRadius ; rc.bottom = nYPhilosopher + nRadius ; Ellipse(hdc, rc.left, rc.top, rc.right, rc.bottom) ; SetTextColor(hdc, 0x0) ; StringCchPrintf(szName, 16, TEXT("哲學家 %d"), nPos + 1) ; DrawText(hdc, szName, -1, &rc, DT_CENTER | DT_SINGLELINE | DT_VCENTER) ; if (g_nChopstickUser[nPos] == nPos) { dRadian = (nPos * dAngle) / ANGLE_PER_RADIAN ; x = g_ptWinOrg.x + (int)(sin(dRadian) * g_nRadiusTable * 0.9) ; y = g_ptWinOrg.y - (int)(cos(dRadian) * g_nRadiusTable * 0.9) ; MoveToEx(hdc, x, y, NULL) ; LineTo(hdc, nXPhilosopher, nYPhilosopher) ; } nPosNext = nPos + 1 ; if (nPosNext >= PHILOSOPERS) nPosNext = 0 ; if (g_nChopstickUser[nPosNext] == nPos) { dRadian = (nPosNext * dAngle) / ANGLE_PER_RADIAN ; x = g_ptWinOrg.x + (int)(sin(dRadian) * g_nRadiusTable * 0.9) ; y = g_ptWinOrg.y - (int)(cos(dRadian) * g_nRadiusTable * 0.9) ; MoveToEx(hdc, x, y, NULL) ; LineTo(hdc, nXPhilosopher, nYPhilosopher) ; } DeleteObject(SelectObject(hdc, hPenOld)) ; } DeleteObject(SelectObject(hdc, hFontOld)) ; } LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { int wmId, wmEvent; PAINTSTRUCT ps; HDC hdc; switch (message) { case WM_CREATE: /**** * 部分選項置灰 * waitformultipleobjects,create thread, resume thread. **/ EnableMenuItem(GetMenu(hWnd), IDM_WAITFORMULTIPLEOBJECTS, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_CREATETHREAD, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_RESUMETHREAD, MF_GRAYED | MF_BYCOMMAND); break; case WM_COMMAND: wmId = LOWORD(wParam); wmEvent = HIWORD(wParam); // Parse the menu selections: switch (wmId) { case IDM_WAITFORMULTIPLEOBJECTS: /**** * 點擊:waitformultipleobjects **/ EnableMenuItem(GetMenu(hWnd), IDM_WAITFORMULTIPLEOBJECTS, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_FASTDEADLOCK, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_SLOWDEADLOCK, MF_ENABLED | MF_BYCOMMAND); g_bWaitMultiple = TRUE; g_bFastDining = FALSE; break; case IDM_FASTDEADLOCK: /**** * 點擊:fast deadlock **/ EnableMenuItem(GetMenu(hWnd), IDM_WAITFORMULTIPLEOBJECTS, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_FASTDEADLOCK, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_SLOWDEADLOCK, MF_ENABLED | MF_BYCOMMAND); g_bWaitMultiple = FALSE; g_bFastDining = TRUE; break; case IDM_SLOWDEADLOCK: /**** * 點擊:slow deadlock **/ EnableMenuItem(GetMenu(hWnd), IDM_WAITFORMULTIPLEOBJECTS, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_FASTDEADLOCK, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_SLOWDEADLOCK, MF_GRAYED | MF_BYCOMMAND); g_bWaitMultiple = FALSE; g_bFastDining = FALSE; break; case IDM_CREATETHREAD: /**** * 點擊:create thread **/ EnableMenuItem(GetMenu(hWnd), IDM_CREATETHREAD, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_TERMINATETHREAD, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_SUSPENDTHREAD, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_RESUMETHREAD, MF_GRAYED | MF_BYCOMMAND); Dining(); break; case IDM_SUSPENDTHREAD: /**** * 點擊:suspend thread **/ EnableMenuItem(GetMenu(hWnd), IDM_SUSPENDTHREAD, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_RESUMETHREAD, MF_ENABLED | MF_BYCOMMAND); for (int i = 0; i < PHILOSOPERS; i++) { SuspendThread(g_hPhilosThread[i]); } break; case IDM_RESUMETHREAD: /**** * 點擊:resume thread **/ EnableMenuItem(GetMenu(hWnd), IDM_SUSPENDTHREAD, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_RESUMETHREAD, MF_GRAYED | MF_BYCOMMAND); for (int i = 0; i < PHILOSOPERS; i++) { ResumeThread(g_hPhilosThread[i]); } case IDM_TERMINATETHREAD: /**** * 點擊:terminate thread **/ EnableMenuItem(GetMenu(hWnd), IDM_TERMINATETHREAD, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_CREATETHREAD, MF_ENABLED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_RESUMETHREAD, MF_GRAYED | MF_BYCOMMAND); EnableMenuItem(GetMenu(hWnd), IDM_SUSPENDTHREAD, MF_GRAYED | MF_BYCOMMAND); for (int i = 0 ; i < PHILOSOPERS ; i++) { TerminateThread(g_hPhilosThread[i], i); g_nDinerState[i] = RESTING; g_nChopstickUser[i] = UNUSED; } /* 重繪 */ InvalidateRect(hWnd, NULL, TRUE); break; case IDM_EXIT: DestroyWindow(hWnd); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } /**** * 窗口菜單修改后刷新 **/ DrawMenuBar(hWnd) ; break; case WM_FORCE_REPAINT: /**** * 自定義刷新畫面 **/ { MSG msg; InvalidateRect(hWnd, NULL, TRUE); while (PeekMessage(&msg, hWnd, WM_FORCE_REPAINT, WM_FORCE_REPAINT, PM_REMOVE)); } break; case WM_PAINT: hdc = BeginPaint(hWnd, &ps); /**** * **/ RenderFrame(hdc); EndPaint(hWnd, &ps); break; case WM_DESTROY: /**** * 刪除資源 **/ for (int i = 0; i < PHILOSOPERS; i++) { CloseHandle(g_hChopstickMutex[i]); TerminateThread(g_hPhilosThread[i], i); } PostQuitMessage(0); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } return 0; } // Message handler for about box. INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam) { UNREFERENCED_PARAMETER(lParam); switch (message) { case WM_INITDIALOG: return (INT_PTR)TRUE; case WM_COMMAND: if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL) { EndDialog(hDlg, LOWORD(wParam)); return (INT_PTR)TRUE; } break; } return (INT_PTR)FALSE; }