基于socket的TCP编程

#include <winsock2.h> #include <stdio.h> #include <stdlib.h> // void main() // { // WORD wVersionRequested; // WSADATA wsaData; // int err; // // wVersionRequested = MAKEWORD( 1, 1 ); // // err = WSAStartup( wVersionRequested, &wsaData ); // if ( err != 0 ) { // /* Tell the user that we could not find a usable */ // /* WinSock DLL. */ // return; // } // // /* Confirm that the WinSock DLL supports 2.2.*/ // /* Note that if the DLL supports versions greater */ // /* than 2.2 in addition to 2.2, it will still return */ // /* 2.2 in wVersion since that is the version we */ // /* requested. */ // // if ( LOBYTE( wsaData.wVersion ) != 1 || // HIBYTE( wsaData.wVersion ) != 1 ) { // /* Tell the user that we could not find a usable */ // /* WinSock DLL. */ // printf("It is not the requested version!"); // WSACleanup( ); // return; // } // // SOCKET socketSrv = socket(AF_INET,SOCK_STREAM,0); // SOCKADDR_IN addrSrv; // addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY); // addrSrv.sin_family = AF_INET; // addrSrv.sin_port = htons(6000); // // bind(socketSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR)); // listen(socketSrv,5); // // SOCKADDR_IN addrClient; // int len = sizeof(SOCKADDR); // while(1) // { // SOCKET socketConn = accept(socketSrv,(SOCKADDR*)&addrClient,&len); // char sendBuf[100]; // sprintf(sendBuf,"Welcome %s to http://hi.baidu.com",inet_ntoa(addrClient.sin_addr)); // // send(socketConn,sendBuf,strlen(sendBuf)+1,0); // // char recvBuf[100]; // recv(socketConn,recvBuf,strlen(recvBuf)+1,0); // printf("%s\n",recvBuf); // closesocket(socketConn); // } // /* The WinSock DLL is acceptable. Proceed. */ // } /*事件对象I/O管理程序实例*/ #define WSA_MAXIMUN_EVENTS 64 #define MAX_BUF_LEN 1024 void CompressArrays(int Index, WSAEVENT Event[WSA_MAXIMUM_WAIT_EVENTS], SOCKET Socket[WSA_MAXIMUM_WAIT_EVENTS], unsigned long *EventTotal); void main() { WORD wVersionRequested; WSADATA wsaData; int err; wVersionRequested = MAKEWORD( 1, 1 ); err = WSAStartup( wVersionRequested, &wsaData ); if ( err != 0 ) { /* Tell the user that we could not find a usable */ /* WinSock DLL. */ return; } /* Confirm that the WinSock DLL supports 2.2.*/ /* Note that if the DLL supports versions greater */ /* than 2.2 in addition to 2.2, it will still return */ /* 2.2 in wVersion since that is the version we */ /* requested. */ if ( LOBYTE( wsaData.wVersion ) != 1 || HIBYTE( wsaData.wVersion ) != 1 ) { /* Tell the user that we could not find a usable */ /* WinSock DLL. */ printf("It is not the requested version!"); WSACleanup( ); return; } SOCKET SocketArray[WSA_MAXIMUN_EVENTS]; SOCKET socketSrv = socket(AF_INET,SOCK_STREAM,0); SOCKADDR_IN addrSrv; addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY); addrSrv.sin_family = AF_INET; addrSrv.sin_port = htons(6000); bind(socketSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR)); /*创建一个事件对象*/ WSAEVENT NewEvent = WSACreateEvent(); /*在socketsrv套接字上注册套接连接和关闭的网络事件*/ // WSAEventSelect(socketSrv,NewEvent,FD_ACCEPT|FD_CLOSE); if (SOCKET_ERROR == WSAEventSelect(socketSrv,NewEvent,FD_ACCEPT|FD_CLOSE)) { printf("1.WSAEventSelect() failed with error %d\n", WSAGetLastError()); return; } listen(socketSrv,5); WSAEVENT EventArray[WSA_MAXIMUN_EVENTS]; DWORD EventTotal = 0; SocketArray[EventTotal] = socketSrv; EventArray[EventTotal] = NewEvent; EventTotal++; SOCKADDR_IN addrClient; int len = sizeof(SOCKADDR); int Index = 0; WSANETWORKEVENTS NetworkEvents; while(1) { //在所有套接口上等待网络事件的发生 Index = WSAWaitForMultipleEvents(EventTotal,EventArray,FALSE,WSA_INFINITE,FALSE); WSAEnumNetworkEvents(SocketArray[Index-WSA_WAIT_EVENT_0], EventArray[Index-WSA_WAIT_EVENT_0], &NetworkEvents); //检查FD_ACCEPT网络事件 if(NetworkEvents.lNetworkEvents&FD_ACCEPT) { if(0 != NetworkEvents.iErrorCode[FD_ACCEPT_BIT]) { printf("FD_ACCEPT failed with error %d\n",NetworkEvents.iErrorCode[FD_ACCEPT_BIT]); break; } } //接受新的连接，并存入套接字数组 SOCKET socketConn = socket(AF_INET,SOCK_STREAM,0); socketConn = accept(SocketArray[Index-WSA_WAIT_EVENT_0],NULL,NULL); //当套接字的数量超界时，关闭该套接字 if(EventTotal>WSA_MAXIMUN_EVENTS) { printf("Too many connections"); closesocket(socketConn); break; } NewEvent = WSACreateEvent(); // WSAEventSelect(socketConn,NewEvent,FD_READ|FD_WRITE); if (SOCKET_ERROR == WSAEventSelect(socketConn,NewEvent,FD_READ|FD_WRITE|FD_CLOSE)) { printf("WSAEventSelect() failed with error %d\n", WSAGetLastError()); // return; } EventArray[EventTotal] = NewEvent; SocketArray[EventTotal] = socketConn; EventTotal++; //处理FD_READ通知 if(NetworkEvents.lNetworkEvents&FD_READ) { if(0 != NetworkEvents.iErrorCode[FD_READ_BIT]) { printf("FD_READ failed with error %d\n",NetworkEvents.iErrorCode[FD_READ_BIT]); break; } //从套接字读入数据 char recvBuf[MAX_BUF_LEN]; recv(SocketArray[Index-WSA_WAIT_EVENT_0],recvBuf,MAX_BUF_LEN,0); printf("The receive buffer string is: %s\n",recvBuf); } //处理FD_WRITE通知 if(NetworkEvents.lNetworkEvents&FD_WRITE) { if(0 != NetworkEvents.iErrorCode[FD_WRITE_BIT]) { printf("FD_WRITE failed with error %d\n",NetworkEvents.iErrorCode[FD_WRITE_BIT]); break; } //从套接字写入数据 addrClient.sin_addr.S_un.S_addr = inet_addr("210.45.251.236"); char sendBuf[MAX_BUF_LEN]; sprintf(sendBuf,"The server say :Welcome to connect %s !",inet_ntoa(addrClient.sin_addr)); printf("The send buffer string is: %s\n",sendBuf); //发送数据 send(SocketArray[Index-WSA_WAIT_EVENT_0],sendBuf,strlen(sendBuf)+1,0); } //处理FD_CLOSE通知 if(NetworkEvents.lNetworkEvents&FD_CLOSE) { if(0 != NetworkEvents.iErrorCode[FD_CLOSE_BIT]) { printf("FD_CLOSE failed with error %d\n",NetworkEvents.iErrorCode[FD_CLOSE_BIT]); break; } //关闭套接字 closesocket(SocketArray[Index-WSA_WAIT_EVENT_0]); CompressArrays(Index-WSA_WAIT_EVENT_0,EventArray,SocketArray,&EventTotal); } } WSACleanup(); } void CompressArrays(int Index, WSAEVENT Event[WSA_MAXIMUM_WAIT_EVENTS], SOCKET Socket[WSA_MAXIMUM_WAIT_EVENTS], unsigned long *EventTotal) { //压缩数组，将Index后的数组项往前移以覆盖无效的项 for(int i=Index;i<WSA_MAXIMUM_WAIT_EVENTS;i++) { Event[i]=Event[i+1]; Socket[i]=Socket[i+1]; } --(*EventTotal); }