Windows网络编程附书代码(简单的服务器与客户端)

 

//程序清单6-1 回应服务器代码// 编译命令Compile：cl -o Server Server.c ws2_32.lib//// 命令行选项：// server [-p:x] [-i:IP] [-o]// -p:x 监听的端口号// -i:str 监听的网卡// -o 只接收，不回显数据//#include <winsock2.h>#include <stdio.h>#include <stdlib.h>#pragma  comment(lib, "Ws2_32.lib ")#define DEFAULT_PORT 5150#define DEFAULT_BUFFER 4096int iPort = DEFAULT_PORT; // 监听客户端的端口BOOL bInterface = FALSE, // 在指定网卡上监听bRecvOnly = FALSE; // 只接收，不回显char szAddress[128];void usage() ;void ValidateArgs(int argc, char **argv) ;DWORD WINAPI ClientThread(LPVOID lpParam) ;// 函数：main// 说明：执行主线程、初始化Winsock、解释命令行参数、创建监听套接字、捆绑到本地地址、//等待// 客户端连接int main(int argc, char **argv){WSADATA wsd;SOCKET sListen,sClient;int iAddrSize;HANDLE hThread;DWORD dwThreadId;struct sockaddr_in local, client;int i = 0 ;printf("程序开始:\n");//ValidateArgs(argc, argv);if (WSAStartup(MAKEWORD(2,2), &wsd) != 0){printf("Failed to load Winsock!\n");return 1;}// 创建监听套接字sListen = socket(AF_INET, SOCK_STREAM, IPPROTO_IP);if (sListen == SOCKET_ERROR){printf("socket() failed: %d\n", WSAGetLastError());return 1;}// 选择本地网络接口卡，并且捆绑到它上面if (bInterface){local.sin_addr.s_addr = inet_addr(szAddress);if (local.sin_addr.s_addr == INADDR_NONE)usage();}elselocal.sin_addr.s_addr = htonl(INADDR_ANY);local.sin_family = AF_INET;local.sin_port = htons(iPort);if (bind(sListen, (struct sockaddr *)&local,sizeof(local)) == SOCKET_ERROR){printf("bind() failed: %d\n", WSAGetLastError());return 1;}listen(sListen, 8);// 循环等待进入的客户端连接，一旦检查到连接，创建线程并且传递句柄printf("主程序循环前:\n");while (1){printf("主程序第%d循环\n",i);iAddrSize = sizeof(client);sClient = accept(sListen, (struct sockaddr *)&client,&iAddrSize);   //会挂起，直到有连接if (sClient == INVALID_SOCKET){printf("accept() failed: %d\n", WSAGetLastError());break;}printf("Accepted client: %s:%d\n",inet_ntoa(client.sin_addr), ntohs(client.sin_port));hThread = CreateThread(NULL, 0, ClientThread,(LPVOID)sClient, 0, &dwThreadId);  //创建处理纯种if (hThread == NULL){printf("CreateThread() failed: %d\n", GetLastError());break;}CloseHandle(hThread);i++ ;}closesocket(sListen);WSACleanup();printf("程序结束:\n");return 0;}// 函数：ClientThread// 说明：函数以线程方式调用，并且处理给定客户端连接，传递参数为从accept()调用中返回//的套接// 字句柄，该函数从客户端读取数据，并且将读到的数据写回去DWORD WINAPI ClientThread(LPVOID lpParam){SOCKET sock=(SOCKET)lpParam;char szBuff[DEFAULT_BUFFER];int ret,nLeft,idx;printf("Client开始:\n");while(1){// 阻塞recv()调用printf("recv开始:\n");ret = recv(sock, szBuff, DEFAULT_BUFFER, 0);if (ret == 0) // 常规关闭break;else if (ret == SOCKET_ERROR){printf("recv() failed: %d\n", WSAGetLastError());break;}szBuff[ret] = '\0';printf("RECV: '%s'\n", szBuff);//// 选择回显数据if (!bRecvOnly){nLeft = ret;idx = 0;// 确保写所有数据while(nLeft > 0){ret = send(sock, &szBuff[idx], nLeft, 0);if (ret == 0)break;else if (ret == SOCKET_ERROR){printf("send() failed: %d\n",WSAGetLastError());break;}nLeft -= ret;idx += ret;}}}printf("Client结束:\n");return 0;}// 监听客户端的网卡// 函数：usage// 说明：打印使用信息，并且退出void usage(){printf("usage: server [-p:x] [-i:IP] [-o]\n\n");printf(" -p:x 监听的端口号\n");printf(" -i:str 监听的网卡\n");printf(" -o 只接收，不回显数据\n\n");ExitProcess(1);}// 函数：ValidateArgs// 说明：解释命令行参数，设置指示操作如何进行的全局变量void ValidateArgs(int argc, char **argv){int i;printf("解释命令行参数程序开始:\n");for(i = 1; i < argc; i++){if ((argv[i][0] == '-') || (argv[i][0] == '/')){switch (tolower(argv[i][1])){case 'p':iPort = atoi(&argv[i][3]);break;case 'i':bInterface = TRUE;if (strlen(argv[i]) > 3)strcpy(szAddress, &argv[i][3]);break;case 'o':bRecvOnly = TRUE;break;default:usage();break;}}}printf("解释命令行参数程序结束:\n");}

 

 

/*程序清单6-2 是客户端代码，客户端建立一个套接字，并对投入应用的服务器名进行解析，然后与服务器建立连接。连接一旦建成，就可发送大量的消息了。每次发送数据之后，客户端都会等待服务器发回的回应。客户端把得自套接字的数据打印出来。回应客户端和服务器不能完全说明TCP 协议的流式传输。这是因为读取操作是在写操作之后进行的，至少客户端这一端是这样的。当然，对服务器来说，还有另一种方式。因此，服务器每次调用读取函数，一般都会返回客户端发出的整条消息。但不要误会，如果客户端的消息大到超过了TCP 的最大传输单元，在线上，它会被分成几个小的数据包，这种情况下，接收端需要多次执行接收调用，才能收完整条消息。为了更好地说明流式传输，运行客户端和服务器时带上-O 选项即可。这样，客户端便只管发送数据，接收端只管读取数据。  服务器如下执行：server -p:5150 -o而客户端如下执行：client -p:5150 -s:IP -n:10 -o大家最可能见到的是客户端进行了10 次send 调用，而服务器在一次或两次recv 调用中，就读取了10 条消息。*///程序清单6-2 回应客户端代码// 说明：回显客户端，连接TCP 服务器，发送数据，并且读服务器返回的数据// 编译命令：cl -o Client Client.c ws2_32.lib//// 命令行参数：// client [-p:x] [-s:IP] [-n:x] [-o]// -p:x 发送的远程端口// -s:IP 服务器IP 地址或主机名// -n:x 发送消息次数// -o 只发送消息，不接收//#include <winsock2.h>#include <stdio.h>#include <stdlib.h>#pragma  comment(lib, "Ws2_32.lib ")#define DEFAULT_COUNT 1000#define DEFAULT_PORT 5150#define DEFAULT_BUFFER 2048#define DEFAULT_MESSAGE "This is a test of the emergency \broadcasting system"char szServer[128], // 连接的服务器szMessage[1024]; // 发送给服务器的消息int iPort = DEFAULT_PORT; // 连接到服务器的端口DWORD dwCount = DEFAULT_COUNT; // 发送消息次数BOOL bSendOnly = FALSE; // 只发送数据，不接收 void usage() ; void ValidateArgs(int argc, char **argv) ;// 函数：main// 说明：执行主线程，初始化Winsock，解释命令行参数，创建套接字，连接服务器，然后发送//和接// 收数据int main(int argc, char **argv){WSADATA wsd;SOCKET sClient;char szBuffer[DEFAULT_BUFFER];int ret,i;struct sockaddr_in server;struct hostent *host = NULL;// 解释命令行并且载入WinsockValidateArgs(argc, argv);if (WSAStartup(MAKEWORD(2,2), &wsd) != 0){printf("Failed to load Winsock library!\n");return 1;}strcpy(szMessage, DEFAULT_MESSAGE);// 创建套接字，并且尝试连接服务器sClient = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);if (sClient == INVALID_SOCKET){printf("socket() failed: %d\n", WSAGetLastError());return 1;}server.sin_family = AF_INET;server.sin_port = htons(iPort);server.sin_addr.s_addr = inet_addr(szServer);// 如果提供的服务器地址不是形如"aaa.bbb.ccc.ddd"，则为主机名，尝试解析它if (server.sin_addr.s_addr == INADDR_NONE){host = gethostbyname(szServer);if (host == NULL){printf("Unable to resolve server: %s\n", szServer);return 1;}CopyMemory(&server.sin_addr, host->h_addr_list[0],host->h_length);}if (connect(sClient, (struct sockaddr *)&server,sizeof(server)) == SOCKET_ERROR){printf("connect() failed: %d\n", WSAGetLastError());return 1;}// 发送和接收数据for(i = 0; i < dwCount; i++){ret = send(sClient, szMessage, strlen(szMessage), 0);if (ret == 0)break;else if (ret == SOCKET_ERROR){printf("send() failed: %d\n", WSAGetLastError());break;}printf("Send %d bytes\n", ret);if (!bSendOnly){ret = recv(sClient, szBuffer, DEFAULT_BUFFER, 0);if (ret == 0) // Graceful closebreak;else if (ret == SOCKET_ERROR){printf("recv() failed: %d\n", WSAGetLastError());break;}szBuffer[ret] = '\0';printf("RECV [%d bytes]: '%s'\n", ret, szBuffer);}}closesocket(sClient);WSACleanup();return 0;} void usage(){printf("usage: client [-p:x] [-s:IP] [-n:x] [-o]\n\n");printf(" -p:x Remote port to send to\n");printf(" -s:IP Server's IP address or hostname\n");printf(" -n:x Number of times to send message\n");printf(" -o Send messages only; don't receive\n");ExitProcess(1);}// 函数：ValidateArgs// 说明：解释命令行参数，设置全局变量void ValidateArgs(int argc, char **argv){int i;for(i = 1; i < argc; i++){if ((argv[i][0] == '-') || (argv[i][0] == '/')){switch (tolower(argv[i][1])){case 'p': // Remote portif (strlen(argv[i]) > 3)iPort = atoi(&argv[i][3]);break;case 's': // Serverif (strlen(argv[i]) > 3)strcpy(szServer, &argv[i][3]);break;case 'n': // Number of times to send messageif (strlen(argv[i]) > 3)dwCount = atol(&argv[i][3]);break;case 'o': // Only send message; don't receivebSendOnly = TRUE;break;default:usage();break;}}}}