Linux 即时聊天系统（tcp）epoll 版

 //头文件
 1 #include <arpa/inet.h>
 2 #include <sys/socket.h>
 3 #include <netinet/in.h>
 4 #include <stdio.h>
 5 #include <netdb.h>
 6 #include <string.h>
 7 #include <sys/types.h>
 8 #include <sys/socket.h>
 9 #include <unistd.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <errno.h>
13 #include <sys/time.h>
14 #include <sys/epoll.h>
15 #include <signal.h>

  //服务端代码
  1 #include"func.h"
  2     
  3 int main(int argc,char *argv[]){
  4     //socket
  5     int sfd = socket(AF_INET,SOCK_STREAM,0);
  6     if(sfd == -1){
  7         perror("sfd");
  8         return -1;
  9     }
 10     //bind
 11     struct sockaddr_in server;
 12     memset(&server,0,sizeof(struct sockaddr_in));
 13     server.sin_family = AF_INET;
 14     server.sin_port = htons(atoi(argv[2]));
 15     server.sin_addr.s_addr = inet_addr(argv[1]);
 16     int ret;
 17     ret = bind(sfd,(struct sockaddr *)&server,sizeof(server));
 18     if(ret == -1){
 19         perror("bind");
 20         return -1;
 21     }
 22     //listen
 23     ret = listen(sfd,10);
 24     if(ret == -1){
 25         perror("listen");
 26         return -1;
 27     }
 28     
 29     printf("i am server\n");
 30     
 31     //epoll创建
 32     int epfd = epoll_create(1);
 33 
 34     struct epoll_event event,evs[3];
 35     //注册sfd
 36     memset(&event,0,sizeof(event));
 37     event.events = EPOLLIN;
 38     event.data.fd = sfd;
 39     epoll_ctl(epfd,EPOLL_CTL_ADD,sfd,&event);
 40     //注册0
 41     memset(&event,0,sizeof(event));
 42     event.events = EPOLLIN;
 43     event.data.fd = 0;
 44     epoll_ctl(epfd,EPOLL_CTL_ADD,0,&event);
 45     
 46     int ret1,i,len,new_fd;
 47     char buf[128]={0};
 48 
 49     //新建client
 50     struct sockaddr_in client;
 51     while(1){
 52         memset(evs,0,sizeof(evs));
 53         int ret1 = epoll_wait(epfd,evs,3,-1);
 54         if(ret1 > 0){
 55             for(i=0; i<ret1; i++){
 56                 //sfd 有client请求建立里连接
 57                 if(evs[i].data.fd == sfd){                
 58                     memset(&client,0,sizeof(client));
 59                     len = sizeof(client);
 60                     new_fd = accept(sfd,(struct sockaddr*)&client,&len);
 61                     if(new_fd == -1){
 62                         perror("accept");
 63                         return -1;
 64                     }
 65                     //注册new_fd
 66                     memset(&event,0,sizeof(event));
 67                     event.events = EPOLLIN;
 68                     event.data.fd = new_fd;
 69                     epoll_ctl(epfd,EPOLL_CTL_ADD,new_fd,&event);
 70                     //打印客户端ip，端口
 71                     printf("client ip=%s,port=%d\n",inet_ntoa(client.sin_addr),ntohs(client.sin_port));
 72                 }
 73                 //0 服务端输入
 74                 if(evs[i].data.fd == 0){
 75                     memset(buf,0,sizeof(buf));
 76                     ret = read(0,buf,sizeof(buf));            
 77                     if(ret <= 0){
 78                         printf("bye bye\n");
 79                         close(new_fd);
 80                         //删除new_fd
 81                         memset(&event,0,sizeof(event));
 82                         event.events = EPOLLIN;
 83                         event.data.fd = new_fd;
 84                         epoll_ctl(epfd,EPOLL_CTL_DEL,new_fd,&event);
 85                         break;
 86                     }
 87                     ret = send(new_fd,buf,strlen(buf)-1,0);
 88                     if(ret == -1){
 89                         perror("send");
 90                         return -1;
 91                     }
 92                 }
 93                 //new_fd 读客户端的数据
 94                 if(evs[i].data.fd == new_fd){
 95                     memset(buf,0,sizeof(buf));
 96                     ret = recv(new_fd,buf,sizeof(buf),0);
 97                     if(ret == -1){
 98                         perror("recv");
 99                         return -1;
100                     }else if(ret == 0){
101                         printf("bye bye\n");
102                         close(new_fd);
103                         //删除new_fd
104                         memset(&event,0,sizeof(event));
105                         event.events = EPOLLIN;
106                         event.data.fd = new_fd;
107                         epoll_ctl(epfd,EPOLL_CTL_DEL,new_fd,&event);
108                         break;
109                     }
110                     printf("%s\n",buf);
111                 }
112             }
113         }
114     }
115     close(sfd);//关闭sfd
116     close(new_fd);//关闭new_fd
117     close(epfd);//关闭epfd
118     return 0;    
119 }

 //客户端代码(客户端并未使用epoll，有兴趣的可以自己进行修改)
 1 #include"func.h"
 2 
 3 int main(int argc,char *argv[]){
 4     //socket
 5     int sfd = socket(AF_INET,SOCK_STREAM,0);
 6     if(sfd == -1){
 7         perror("socket");
 8         return -1;
 9     }
10     //connect
11     int ret;
12     struct sockaddr_in ser;
13     memset(&ser,0,sizeof(ser));
14     ser.sin_family = AF_INET;
15     ser.sin_addr.s_addr = inet_addr(argv[1]);
16     ser.sin_port = htons(atoi(argv[2]));
17     ret = connect(sfd,(struct sockaddr*)&ser,sizeof(ser));
18     if(ret == -1){
19         perror("connect");
20         return -1;
21     }
22     printf("i am client\n");
23     char buf[128]={0};
24     fd_set rdset;
25     while(1){
26         FD_ZERO(&rdset);
27         FD_SET(0,&rdset);
28         FD_SET(sfd,&rdset);
29         ret = select(sfd+1,&rdset,NULL,NULL,NULL);
30         if(ret > 0){
31             if(FD_ISSET(0,&rdset)){
32                 memset(buf,0,sizeof(buf));
33                 ret = read(0,buf,sizeof(buf));            
34                 if(ret <= 0){
35                     printf("bye bye\n");
36                     break;
37                 }
38                 ret = send(sfd,buf,strlen(buf)-1,0);
39                 if(ret == -1){
40                     perror("send");
41                     return -1;
42                 }
43             }
44             if(FD_ISSET(sfd,&rdset)){
45                 memset(buf,0,sizeof(buf));
46                 ret = recv(sfd,buf,sizeof(buf),0);
47                 if(ret == -1){
48                     perror("recv");
49                     return -1;
50                 }else if(ret == 0){
51                     printf("bye bye\n");
52                     break;
53                 }
54                 printf("%s\n",buf);
55             }
56         }
57     }
58     close(sfd);
59 
60     return 0;    
61 }