基于Overlapped IO的TCP服务器模型

   用了一个工作线程，可管理64个TCP连接。

 

// OverlappedIO.cpp : Defines the entry point for the console application.//#include "stdafx.h"using std::map;#define DATA_BUFSIZE 4096DWORD g_udwIndexEvent = 0;CRITICAL_SECTION g_CSListClients;HANDLE g_hThreadServer;HANDLE g_hEventConn;typedef struct MapClientNode{SOCKETsock;WSAEVENTtEvent;DWORDudwRecvBytes;WSABUFtBuf;WSAOVERLAPPEDtOverLp;boolbHasHandled;}_CLIENT;typedef map<WSAEVENT, _CLIENT> MAP_CLIENT;MAP_CLIENT g_mapClient;#define _ENTER_CS_CLT EnterCriticalSection(&g_CSListClients)#define _LEAVE_CS_CLT LeaveCriticalSection(&g_CSListClients)int WriteToArray(MAP_CLIENT::iterator begin, MAP_CLIENT::iterator end, WSAEVENT *aEvents){int c = 0;for (; begin != end; ++begin){if (false == begin->second.bHasHandled){aEvents[c++] = begin->second.tEvent;}}return c;}//工作线程unsigned int __stdcall ServerProc(void *pvParam){DWORD udwFlags = 0;MAP_CLIENT::iterator iter;WSAEVENT aEvents[WSA_MAXIMUM_WAIT_EVENTS];for (;;){WaitForSingleObject(g_hEventConn, INFINITE);_ENTER_CS_CLT;//这个是主要部分，对每个需要投递WSARecv的连接投递一次for (iter = g_mapClient.begin(); iter != g_mapClient.end();){if (iter->second.bHasHandled && (WSARecv(iter->second.sock, &iter->second.tBuf, 1, &iter->second.udwRecvBytes,&udwFlags, &iter->second.tOverLp, NULL) == SOCKET_ERROR)){iter->second.bHasHandled = false;switch (WSAGetLastError()){case WSAENOBUFS:++iter;break;case WSA_IO_PENDING:++iter;break;default:closesocket(iter->second.sock);WSACloseEvent(iter->second.tEvent);g_mapClient.erase(iter++);break;}}else{++iter;}}//把完成投递但是没被处理的事件写到一个缓冲区中int c = WriteToArray(g_mapClient.begin(), g_mapClient.end(), aEvents);//等待其中一个的完成，如果超时就返回再重复DWORD dwIndex = WSAWaitForMultipleEvents(c, aEvents, false, 100, false);if (WSA_WAIT_TIMEOUT == dwIndex){_LEAVE_CS_CLT;continue;}dwIndex -= WSA_WAIT_EVENT_0;WSAEVENT tEvent = aEvents[dwIndex];WSAResetEvent(tEvent);//解析事件，读取报文_CLIENT *ptClient = &g_mapClient[tEvent];WSAGetOverlappedResult(ptClient->sock, &ptClient->tOverLp, &ptClient->udwRecvBytes, false, &udwFlags);ptClient->bHasHandled = true;if (0 == ptClient->udwRecvBytes){closesocket(ptClient->sock);WSACloseEvent(tEvent);delete[] ptClient->tBuf.buf;g_mapClient.erase(tEvent);printf("connection closed/n");if (g_mapClient.empty()){printf("no connection/n");ResetEvent(g_hEventConn);}}else{ptClient->tBuf.buf[ptClient->udwRecvBytes] = 0;printf("%s/n", ptClient->tBuf.buf);ZeroMemory(&ptClient->tOverLp, sizeof(WSAOVERLAPPED));ptClient->tOverLp.hEvent = ptClient->tEvent;}_LEAVE_CS_CLT;}return 0;}int main(int argc, char* argv[]){//一些初始化工作InitializeCriticalSection(&g_CSListClients);g_hEventConn = CreateEvent(NULL, true, false, NULL);WSADATA wsaData;WSAStartup(MAKEWORD(2,2),&wsaData);//创建一个TCP套接字，带上WSA_FLAG_OVERLAPPED标志SOCKET ListenSocket = WSASocket(AF_INET,SOCK_STREAM,0,NULL,0,WSA_FLAG_OVERLAPPED);//创建用于AcceptEx的缓冲区和事件对象unsigned char ucBuf[256] = {0}; WSAOVERLAPPED AcceptOverlapped;WSAEVENT hWsaEventAccept = WSACreateEvent();//bind地址开始监听SOCKADDR_IN ServerAddr;ServerAddr.sin_family = AF_INET;ServerAddr.sin_addr.S_un.S_addr = INADDR_ANY;ServerAddr.sin_port = htons(1234);bind(ListenSocket,(LPSOCKADDR)&ServerAddr,sizeof(ServerAddr));listen(ListenSocket,5);//起一个工作线程，用于处理客户端连接ResetEvent(g_hEventConn);g_hThreadServer = (HANDLE)_beginthreadex(NULL, 0, ServerProc, NULL, 0, NULL);for (;;){DWORD udwRecv = 0;ZeroMemory(&AcceptOverlapped, sizeof(WSAOVERLAPPED));AcceptOverlapped.hEvent = hWsaEventAccept;//创建一个新的套接字用于AcceptEx，因为AcceptEx本身不创建套接字SOCKET AcceptSocket = WSASocket(AF_INET,SOCK_STREAM,0,NULL,0,WSA_FLAG_OVERLAPPED);//传递一个overlapped结构，这样就就可以用事件对象来通知AcceptEx(ListenSocket, AcceptSocket, ucBuf, 0, sizeof(SOCKADDR_IN) + 16,sizeof(SOCKADDR_IN) + 16, &udwRecv, &AcceptOverlapped);//等待连接事件的发生，待事件被通知时记得要重置DWORD udwWaitRet = WSAWaitForMultipleEvents(1, &hWsaEventAccept, false, WSA_INFINITE, false);WSAResetEvent(hWsaEventAccept);int dwLocal, dwRemote;sockaddr_in *ptLocalAddr;sockaddr_in *ptRemoteAddr; //解析缓冲区读取远程地址GetAcceptExSockaddrs(ucBuf, 0, sizeof(SOCKADDR_IN) + 16, sizeof(SOCKADDR_IN) + 16,(sockaddr**)&ptLocalAddr, &dwLocal, (sockaddr**)&ptRemoteAddr, &dwRemote);printf("new connection %s-%u/n", inet_ntoa(ptLocalAddr->sin_addr), ntohs(ptRemoteAddr->sin_port));_CLIENT tClient;//填写这个新连接的数据结构字段，包括套接字，缓冲区和事件对象tClient.tEvent= WSACreateEvent();tClient.sock= AcceptSocket;tClient.tBuf.buf= new char[DATA_BUFSIZE];tClient.tBuf.len= DATA_BUFSIZE;ZeroMemory(&tClient.tOverLp.hEvent, sizeof(WSAOVERLAPPED));tClient.tOverLp.hEvent= tClient.tEvent;tClient.bHasHandled= true;_ENTER_CS_CLT;//如果已经有64个连接，那么就报错if (g_mapClient.size() == 64){closesocket(AcceptSocket);printf("too much connection/n");continue;}//插入到工作线程的连接表中g_mapClient.insert(MAP_CLIENT::value_type(tClient.tEvent, tClient));if (1 == g_mapClient.size()){SetEvent(g_hEventConn);}_LEAVE_CS_CLT;}CloseHandle(g_hEventConn);CloseHandle(g_hThreadServer);DeleteCriticalSection(&g_CSListClients);return 0;}