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C++实现异步（重叠）管道通信

news 2025/6/20 6:39:10

主要思路是：

使用重叠 I/O（OVERLAPPED），避免阻塞 ConnectNamedPipe。
额外创建一个“停止事件”（hStopEvent），在线程中与管道事件一起 WaitForMultipleObjects，一旦收到停止事件就马上退出循环。
在主线程（或 OnNcDestroy）中 SetEvent(hStopEvent) 通知线程退出，然后再 CloseHandle 管道和事件。

// 假设这几个都是类成员或全局变量：
HANDLE hPipe = INVALID_HANDLE_VALUE;      // 管道句柄
HANDLE hStopEvent = NULL;                 // 停止事件
HANDLE hOvEvent   = NULL;                 // OVERLAPPED 事件
HANDLE hThread    = NULL;                 // 工作线程句柄bool OpenPipe(MsgHandleInterface* msgHandle)
{// 1. 创建停止事件（自动重置、初始未置位）hStopEvent = CreateEvent(nullptr, FALSE, FALSE, nullptr);if (!hStopEvent) return false;// 2. 创建 OVERLAPPED 专用事件hOvEvent = CreateEvent(nullptr, FALSE, FALSE, nullptr);if (!hOvEvent) {CloseHandle(hStopEvent);return false;}// 3. 创建命名管道，注意 FILE_FLAG_OVERLAPPEDLPCTSTR lpszPipename = TEXT(CMWAITMSGPIPENAME);hPipe = CreateNamedPipe(lpszPipename,PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED,  // 重叠模式PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE | PIPE_WAIT,1,BUFSIZE,BUFSIZE,0,NULL);if (hPipe == INVALID_HANDLE_VALUE) {CloseHandle(hOvEvent);CloseHandle(hStopEvent);return false;}// 4. 启动后台线程DWORD dwThreadId = 0;hThread = CreateThread(NULL,0,waitConnectThread,(LPVOID)msgHandle,    // 如果需要传递 msgHandle，可用结构体打包0,&dwThreadId);if (!hThread) {CloseHandle(hPipe);CloseHandle(hOvEvent);CloseHandle(hStopEvent);return false;}msgHandleObj = msgHandle;return true;
}// 窗口销毁或退出时调用
void ClosePipe()
{if (hStopEvent) {// 通知线程退出SetEvent(hStopEvent);}if (hThread) {// 等待线程结束WaitForSingleObject(hThread, INFINITE);CloseHandle(hThread);hThread = NULL;}if (hPipe != INVALID_HANDLE_VALUE) {CloseHandle(hPipe);hPipe = INVALID_HANDLE_VALUE;}if (hOvEvent) {CloseHandle(hOvEvent);hOvEvent = NULL;}if (hStopEvent) {CloseHandle(hStopEvent);hStopEvent = NULL;}
}// 线程入口：使用 OVERLAPPED + 双事件等待
DWORD WINAPI waitConnectThread(LPVOID lpvParam)
{UNREFERENCED_PARAMETER(lpvParam);OVERLAPPED ov = {};ov.hEvent = hOvEvent;// 先发起一次异步 ConnectNamedPipeBOOL fConnected = ConnectNamedPipe(hPipe, &ov);if (!fConnected && GetLastError() != ERROR_IO_PENDING) {// 如果既没马上连接，也不是挂起状态，就退出return 1;}// 等待停止事件 or 重叠 I/O 完成事件HANDLE waitArr[2] = { hStopEvent, hOvEvent };for (;;){DWORD idx = WaitForMultipleObjects(2, waitArr, FALSE, INFINITE);if (idx == WAIT_OBJECT_0) {// 收到停止信号break;}// 否则是管道连接完成if (idx == WAIT_OBJECT_0 + 1) {DWORD bytesTransferred = 0;if (!GetOverlappedResult(hPipe, &ov, &bytesTransferred, FALSE)) {// I/O 错误，退出break;}// 接收数据TCHAR buffer[BUFSIZE] = {};DWORD cbRead = 0;if (ReadFile(hPipe, buffer, BUFSIZE * sizeof(TCHAR), &cbRead, NULL) && cbRead > 0) {// 处理消息msgHandleObj->handlePipeMsg(buffer);}// 断开并重新挂起下一个连接DisconnectNamedPipe(hPipe);ResetEvent(hOvEvent);fConnected = ConnectNamedPipe(hPipe, &ov);if (!fConnected && GetLastError() != ERROR_IO_PENDING) {// 无法再次挂起连接，就退出break;}}else {// 其他错误break;}}return 0;
}