Linux程序设计上机四(网络编程).doc

计算机学院 网络13卓越班 郑仙玉 学号：201300824401上机四：Linux网络编程一上机目标：（1） 掌握“TCP套接字”编程（2） 掌握“UDP套接字”编程上机实例：（1） 编写TCP客户端和服务器端程序服务器端：能够处理多并发（每个子进程处理一个客户端连接；），实现信息回射（echo）客户端：实现信息发送和显示实验步骤：1） 先建立文件夹TCP，并在TCP文件夹中建立client文件夹和service文件夹：图4-1、TCP文件中的保含文件2） 在service文件夹内建立service.cpp和makefile文件：图4-2、列出service文件夹中的文件 3）在client文件夹内建立client.cpp和Makefile文件：图4-3、列出client文件夹中的文件4） service文件夹中的makefile文件内容：图4-4、service的makefile内容5） client文件夹中的Makefile文件内容：图4-5、client的Makefile内容6） 在终端中service的运行过程：图4-6、service可执行文件的生成7） 在终端中client的运行过程：图4-7、client可执行文件的生成8） 客户机和服务器建立连接截图如下：图4-8、运行service图4-9、运行client9） 客户机向服务器发送信息：图4-10、客户机发送消息图4-11、服务器接收到消息，并回应10） 代码服务器端代码：#include #include #include #include #include #include #include #include #include #include #define SERV_PORT 8888#define SERV_IP 127.0.0.1 /本地回环接口#define LIST 20 /服务器最大接受连接#define MAX_FD 10 /FD_SET支持描述符数量int main(void) int sockfd; int err; int i; int connfd; int fd_allMAX_FD; /保存所有描述符，用于select调用后，判断哪个可读/下面两个备份原因是select调用后，会发生变化，再次调用select前，需要重新赋值 fd_set fd_read; /FD_SET数据备份 fd_set fd_select; /用于select struct timeval timeout; /超时时间备份 struct timeval timeout_select; /用于select struct sockaddr_in serv_addr; /服务器地址 struct sockaddr_in cli_addr; /客户端地址 socklen_t serv_len; socklen_t cli_len; /超时时间设置 timeout.tv_sec = 10; timeout.tv_usec = 0; sockfd = socket(AF_INET, SOCK_STREAM, 0); if(sockfd 0) perror(fail to socket); exit(1); memset(&serv_addr, 0, sizeof(serv_addr); memset(&cli_addr, 0, sizeof(cli_addr); serv_addr.sin_family = AF_INET; serv_addr.sin_port = htons(SERV_PORT); serv_addr.sin_addr.s_addr = inet_addr(SERV_IP); serv_len = sizeof(serv_addr); err = bind(sockfd, (struct sockaddr *)&serv_addr, serv_len); if(err 0) perror(fail to bind); exit(1); err = listen(sockfd, LIST); if(err 0) perror(fail to listen); exit(1); /初始化fd_all数组 memset(&fd_all, -1, sizeof(fd_all); fd_all0 = sockfd; /第一个为监听套接字 FD_ZERO(&fd_read); FD_SET(sockfd, &fd_read); /将监听套接字加入fd_set char buf1024; /读写缓冲区 int num; int maxfd; maxfd = fd_all0; /监听的最大套接字 while(1) /每次都需要重新赋值 fd_select = fd_read; timeout_select = timeout;/ err = select(maxfd+1, &fd_select, NULL, NULL, NULL); err = select(maxfd+1, &fd_select, NULL, NULL, (struct timeval *)&timeout_select); if(err 0) perror(fail to select); exit(1); if(err = 0) printf(timeoutn); /检测监听套接字是否可读 if(FD_ISSET(sockfd, &fd_select) /可读，证明有新客户端连接服务器 cli_len = sizeof(cli_addr); connfd = accept(sockfd, (struct sockaddr *)&cli_addr, &cli_len); if(connfd 0) perror(fail to accept); exit(1); /将新连接套接字加入fd_all及fd_read for(i=0; iMAX_FD; i+) if(fd_alli != -1) continue; else fd_alli = connfd; printf(client fd_all%d joinn, i); break; FD_SET(connfd, &fd_read); if(maxfd connfd) maxfd = connfd; /更新maxfd /从1开始查看连接套接字是否可读，因为上面已经处理过0（sockfd） for(i=1; i 0) if(strncmp(exit, buf, 4) = 0) /客户端退出，关闭套接字，并从监听集合清除 printf(client:fd_all%d exitn, i); FD_CLR(fd_alli, &fd_read); close(fd_alli); fd_alli = -1; continue; /收到 客户端数据并打印 bufnum = 0; printf(receive buf from client fd_all%d is: %sn, i, buf); /回复客户端 num = write(fd_alli, ok, sizeof(ok); if(num 0) perror(fail to write ); exit(1); else printf(send replyn); else /printf(no datan); return 0;客户端代码：#include #include #include #include #include #include #include #include #include #define SERV_PORT 8888#define SERV_IP 127.0.0.1int main(void) int sockfd; int err; int connfd; struct sockaddr_in serv_addr; struct sockaddr_in cli_addr; socklen_t serv_len; socklen_t cli_len; sockfd = socket(AF_INET, SOCK_STREAM, 0); if(sockfd 0) perror(fail to socket); exit(1); memset(&serv_addr, 0, sizeof(serv_addr); memset(&cli_addr, 0, sizeof(cli_addr); serv_addr.sin_family = AF_INET; serv_addr.sin_port = htons(SERV_PORT); serv_addr.sin_addr.s_addr = inet_addr(SERV_IP); serv_len = sizeof(serv_addr);/客户端不需要绑定，直接连接即可 err = connect(sockfd, (struct sockaddr *)&serv_addr, serv_len); if(err 0) /exit代表退出 if(strncmp(exit, buf, 4) = 0) write(sockfd, buf, num); break; write(sockfd, buf, num); num = read(sockfd, buf, 1024); if(num 0) bufnum = 0; printf(server reply: %sn, buf); else printf(error to readn); close(sockfd); return 0;（2） 编写UDP客户端和服务器程序（简单聊天程序）服务器端：能够处理客户端登录、用户列表管理客户端：实现客户端之间的公聊和私聊上机要求：（1） 编写源程序 （2） 编写Makefile文件（3） 编译、运行、调试程序实验步骤：. 创建UDP文件夹，中包含chat_public文件夹和chat_private文件夹图4-12、UDP中的文件夹. 公聊：1） chat_public文件夹中所包含的文件：图4-13、chat_public中的文件2） chat_public中Makefile文件的内容：图4-14、公聊的Makefile内容3） 进入chat_public后，输入make:图4-15、执行make前和执行make后的界面4） 在登录3个人时，服务器终端的显示如下：图4-16、服务器处理处理客户端登录、用户列表管理5） 客户端1、2、3登录、取名如下：客户端1：名为zhengxianyu客户端2：名为xianyu客户端3：名为zheng6） 客户端之间发送聊天消息：客户端1向客户端2发送消息客户端2接收到客户端1的消息客户端2向客户端3发送消息客户端3接收到客户端2的消息客户端3向客户端1发送消息客户端1接收到客户端3的消息7） 源代码：Chatsrv.cpp的代码:#include #include #include #include #include #include #include #include #include #include #include #include pub.h#define ERR_EXIT(m) do perror(m); exit(EXIT_FAILURE); while(0)/ 聊天室成员列表USER_LIST client_list;void do_login(MESSAGE& msg, int sock, struct sockaddr_in *cliaddr);void do_logout(MESSAGE& msg, int sock, struct sockaddr_in *cliaddr);void do_sendlist(int sock, struct sockaddr_in *cliaddr);void chat_srv(int sock)struct sockaddr_in cliaddr;socklen_t clilen;int n;MESSAGE msg;while (1)memset(&msg, 0, sizeof(msg);clilen = sizeof(cliaddr);n = recvfrom(sock, &msg, sizeof(msg), 0, (struct sockaddr *)&cliaddr, &clilen);if (n sin_addr.s_addr;user.port = cliaddr-sin_port;/* 查找用户 */USER_LIST:iterator it;for (it=client_list.begin(); it != client_list.end(); +it)if (strcmp(it-username,msg.body) = 0)break;if (it = client_list.end()/* 没找到用户 */printf(has a user login : %s %s:%dn, msg.body, inet_ntoa(cliaddr-sin_addr), ntohs(cliaddr-sin_port);client_list.push_back(user);/ 登录成功应答MESSAGE reply_msg;memset(&reply_msg, 0, sizeof(reply_msg);reply_msg.cmd = htonl(S2C_LOGIN_OK);sendto(sock, &reply_msg, sizeof(msg), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);int count = htonl(int)client_list.size();/ 发送在线人数sendto(sock, &count, sizeof(int), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);printf(sending user list information to: %s %s:%dn, msg.body, inet_ntoa(cliaddr-sin_addr), ntohs(cliaddr-sin_port);/ 发送在线列表for (it=client_list.begin(); it != client_list.end(); +it)sendto(sock, &*it, sizeof(USER_INFO), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);/ 向其他用户通知有新用户登录for (it=client_list.begin(); it != client_list.end(); +it)if (strcmp(it-username,msg.body) = 0)continue;struct sockaddr_in peeraddr;memset(&peeraddr, 0, sizeof(peeraddr);peeraddr.sin_family = AF_INET;peeraddr.sin_port = it-port;peeraddr.sin_addr.s_addr = it-ip;msg.cmd = htonl(S2C_SOMEONE_LOGIN);memcpy(msg.body, &user, sizeof(user);if (sendto(sock, &msg, sizeof(msg), 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr) 0)ERR_EXIT(sendto);else/* 找到用户 */printf(user %s has already loginedn, msg.body);MESSAGE reply_msg;memset(&reply_msg, 0, sizeof(reply_msg);reply_msg.cmd = htonl(S2C_ALREADY_LOGINED);sendto(sock, &reply_msg, sizeof(reply_msg), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);void do_logout(MESSAGE& msg, int sock, struct sockaddr_in *cliaddr)printf(has a user logout : %s %s:%dn, msg.body, inet_ntoa(cliaddr-sin_addr), ntohs(cliaddr-sin_port);USER_LIST:iterator it;for (it=client_list.begin(); it != client_list.end(); +it)if (strcmp(it-username,msg.body) = 0)break;if (it != client_list.end()client_list.erase(it);/ 向其他用户通知有用户登出for (it=client_list.begin(); it != client_list.end(); +it)if (strcmp(it-username,msg.body) = 0)continue;struct sockaddr_in peeraddr;memset(&peeraddr, 0, sizeof(peeraddr);peeraddr.sin_family = AF_INET;peeraddr.sin_port = it-port;peeraddr.sin_addr.s_addr = it-ip;msg.cmd = htonl(S2C_SOMEONE_LOGOUT);if (sendto(sock, &msg, sizeof(msg), 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr) 0)ERR_EXIT(sendto);void do_sendlist(int sock, struct sockaddr_in *cliaddr)MESSAGE msg;msg.cmd = htonl(S2C_ONLINE_USER);sendto(sock, (const char*)&msg, sizeof(msg), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);int count = htonl(int)client_list.size();/* 发送在线用户数 */sendto(sock, (const char*)&count, sizeof(int), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);/* 发送在线用户列表 */for (USER_LIST:iterator it=client_list.begin(); it != client_list.end(); +it)sendto(sock, &*it, sizeof(USER_INFO), 0, (struct sockaddr *)cliaddr, sizeof(struct sockaddr_in);int main(void)int sock;if (sock = socket(PF_INET, SOCK_DGRAM, 0) 0)ERR_EXIT(socket);struct sockaddr_in servaddr;memset(&servaddr, 0, sizeof(servaddr);servaddr.sin_family = AF_INET;servaddr.sin_port = htons(5188);servaddr.sin_addr.s_addr = htonl(INADDR_ANY);if (bind(sock, (struct sockaddr*)&servaddr, sizeof(servaddr) 0)ERR_EXIT(bind);chat_srv(sock);return 0;Chatcli.cpp的代码：#include #include #include #include #include #include #include #include #include #include #include pub.h#define ERR_EXIT(m) do perror(m); exit(EXIT_FAILURE); while(0)/ 当前用户名char username16;/ 聊天室成员列表USER_LIST client_list;void do_someone_login(MESSAGE& msg);void do_someone_logout(MESSAGE& msg);void do_getlist();void do_chat();void parse_cmd(char* cmdline, int sock, struct sockaddr_in *servaddr);bool sendmsgto(int sock, char* username, char* msg);void parse_cmd(char* cmdline, int sock, struct sockaddr_in *servaddr)char cmd10=0;char *p;p = strchr(cmdline, );if (p != NULL)*p = 0;strcpy(cmd, cmdline);if (strcmp(cmd, exit) = 0)MESSAGE msg;memset(&msg,0,sizeof(msg);msg.cmd = htonl(C2S_LOGOUT);strcpy(msg.body, username);if (sendto(sock, &msg, sizeof(msg), 0, (struct sockaddr *)servaddr, sizeof(struct sockaddr_in) 0)ERR_EXIT(sendto);printf(user %s has logout servern, username);exit(EXIT_SUCCESS);else if (strcmp(cmd, send) = 0)char peername16=0;char msgMSG_LEN=0;/* send user msg */* p p2 */while (*p+ = ) ;char *p2;p2 = strchr(p, );if (p2 = NULL)printf(bad commandn);printf(nCommands are:n);printf(send username msgn);printf(listn);printf(exitn);printf(n);return;*p2 = 0;strcpy(peername, p);while (*p2+ = ) ;strcpy(msg, p2);sendmsgto(sock, peername, msg);else if (strcmp(cmd, list) = 0)MESSAGE msg;memset(&msg, 0, sizeof(msg);msg.cmd = htonl(C2S_ONLINE_USER);if (sendto(sock, &msg, sizeof(msg), 0, (struct sockaddr *)servaddr, sizeof(struct sockaddr_in) username,name) = 0)break;if (it = client_list.end()printf(user %s has not logined servern, name);return false;MESSAGE m;memset(&m,0,sizeof(m);m.cmd = htonl(C2C_CHAT);CHAT_MSG cm;strcpy(cm.username, username);strcpy(cm.msg, msg);memcpy(m.body, &cm, sizeof(cm);/strcpy(m.body,msg);struct sockaddr_inpeeraddr;memset(&peeraddr,0,sizeof(peeraddr);peeraddr.sin_family = AF_INET;peeraddr.sin_addr.s_addr = it-ip;peeraddr.sin_port = it-port;in_addr tmp;tmp.s_addr = it-ip;printf(sending message %s to user %s %s:%dn, msg, name, inet_ntoa(tmp), ntohs(it-port);sendto(sock, (const char*)&m, sizeof(m), 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr);return true;void do_getlist(int sock)int count;recvfrom(sock, &count, sizeof(int), 0, NULL, NULL);printf(has %d users logined servern, ntohl(count);client_list.clear();int n = ntohl(count);for (int i=0; in; i+)USER_INFO user;recvfrom(sock,&user, sizeof(USER_INFO), 0, NULL, NULL);client_list.push_back(user);in_addr tmp;tmp.s_addr = user.ip;printf(%s %s:%dn, user.username, inet_ntoa(tmp), ntohs(user.port);void do_someone_login(MESSAGE& msg)USER_INFO *user = (USER_INFO*)msg.body;in_addr tmp;tmp.s_addr = user-ip;print