Poll functions for multi-user chat under Linux

Client:

#define _gnu_source 1#include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <assert.h> #include <stdio.h> #include <unistd.h> #include <string.h > #include <stdlib.h> #include <poll.h> #include <fcntl.h> #define BUFFER_SIZE 64int Main () {const CH    Ar *ip= "127.0.0.1";    int port=12345;    struct sockaddr_in server_address;    Bzero (&server_address,sizeof (server_address));    Server_address.sin_family=af_inet;    Inet_pton (AF_INET,IP,&AMP;SERVER_ADDRESS.SIN_ADDR);    Server_address.sin_port=htons (port);    int Sockfd=socket (pf_inet,sock_stream,0);    ASSERT (sockfd!=0); if (Connect (SOCKFD, (struct sockaddr *) &server_address,sizeof (server_address)) <0) {printf ("Connection fail        Ed\n ");        Close (SOCKFD);    return 1;    } struct POLLFD fds[2];    Fds[0].fd=0;    fds[0].revents=0;    FDS[1].FD=SOCKFD; Fds[1].events=pollin |    Pollrdhup;  fds[1].revents=0;  Char Read_buf[buffer_size];    int pipefd[2];    int Ret=pipe (PIPEFD);    ASSERT (Ret!=-1);        while (1) {ret=poll (fds,2,-1);            if (ret<0) {printf ("poll failure\n");        Break            } if (Fds[1].revents&pollrdhup) {printf ("server close the connection\n");        Break            } else if (Fds[1].revents&pollin) {memset (read_buf, ' + ', buffer_size);            Recv (fds[1].fd,read_buf,buffer_size-1,0);        printf ("%s\n", read_buf); } if (Fds[0].revents&pollin) {Ret=splice (0,null,pipefd[1],null,32768,splice_f_more |            Splice_f_move); Ret=splice (Pipefd[0],null,sockfd,null,32768,splice_f_more |        Splice_f_move);    }} close (SOCKFD); return 0;}

Server:

#define _gnu_source 1#include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> #include <assert.h> #include <stdio.h> #include <unistd.h> #include <errno.h > #include <string.h> #include <fcntl.h> #include <stdlib.h> #include <poll.h> #define User_    LIMIT 5#define buffer_size 64#define fd_limit 65535struct client_data{struct sockaddr_in address;    Char *write_buf; Char buf[buffer_size];};    int setnonblocking (int fd) {int old_option=fcntl (FD,F_GETFL); int New_option=old_option |    O_nonblock;    Fcntl (fd,f_setfl,new_option); return old_option;}    int main () {const char *ip= "127.0.0.1";    int port=12345;    int ret=0;    int i,j;    struct SOCKADDR_IN address;    Bzero (&address,sizeof (address));    Address.sin_family=af_inet;    Inet_pton (AF_INET,IP,&AMP;ADDRESS.SIN_ADDR);   Address.sin_port=htons (port);    Address.sin_addr.s_addr=inaddr_any; int Listenfd=socket (PF_INET,SOck_stream,0);    ASSERT (listenfd>=0);    Ret=bind (LISTENFD, (struct sockaddr *) &address,sizeof (address));    ASSERT (Ret!=-1);    Ret=listen (listenfd,5);    ASSERT (Ret!=-1);    struct client_data* users= (struct client_data*) calloc (fd_limit,sizeof (struct client_data));    struct POLLFD fds[user_limit+1];    int user_counter=0;        for (i=1;i<=user_limit;++i) {fds[i].fd=-1;    fds[i].events=0;    } FDS[0].FD=LISTENFD; Fds[0].events=pollin |    Pollerr;    fds[0].revents=0;        while (1) {printf ("{\ n");        Ret=poll (fds,user_counter+1,-1);        printf ("}\n");            if (ret<0) {printf ("poll failure\n");        Break } for (I=0;i<user_counter+1;++i) {if (FDS[I].FD==LISTENFD) && (Fds[i].revents&pollin                ) {struct sockaddr_in client_address;                socklen_t client_addrlengh=sizeof (client_address); int Connfd=accept (LISTENFD, (Struct SOCKADDR *) &client_address,&client_addrlengh);                    if (connfd<0) {printf ("errno is:%d\n", errno);                Continue                    } if (user_counter>=user_limit) {const char *info= "too many users\n";                    printf ("%s", info);                    Send (Connfd,info,strlen (info), 0);                    Close (CONNFD);                Continue                } user_counter++;                users[connfd].address=client_address;                Setnonblocking (CONNFD);                FDS[USER_COUNTER].FD=CONNFD; Fds[user_counter].events=pollin | pollrdhup|                Pollerr;                fds[user_counter].revents=0;            printf ("comes a new User,now has%d users\n", user_counter);                } else if (Fds[i].revents&pollerr) {printf ("Get an error from%d \ n", FDS[I].FD); Char errors[100];                memset (Errors, ' 100 ');                socklen_t length=sizeof (Errors);  if (getsockopt (fds[i].fd,sol_socket,so_error,&errors,&length) <0) {printf ("get                Socket option failed\n ");            } continue; } else if (fds[i].revents&pollrdhup) {USERS[FDS[I].FD]=USERS[FDS[USER_COUNTER].FD                ];                Close (FDS[I].FD);                Fds[i]=fds[user_counter];                i--;                user_counter--;            printf ("A client left\n");                } else if (fds[i].revents&pollin) {int connfd=fds[i].fd;                memset (users[connfd].buf, ' buffer_size-1 ');                RET=RECV (connfd,users[connfd].buf,buffer_size-1,0); if (ret<0) {if (Errno!=eagain) {Close (connf                   D);     USERS[FDS[I].FD]=USERS[FDS[USER_COUNTER].FD];                        Fds[i]=fds[user_counter];                        i--;                    user_counter--;                    }} else if (ret==0) {} else {                        for (J=1;J&LT;=USER_COUNTER;++J) {if (FDS[J].FD==CONNFD)                        {continue;                        } fds[j].events |=~pollin;                        Fds[j].events |=pollout;                    Users[fds[j].fd].write_buf=users[connfd].buf; }}} and else if (fds[i].revents&pollout) {int connfd=fds[                I].FD;                if (!USERS[CONNFD].WRITE_BUF) {continue; } ret=send (Connfd,users[connfd].write_buf,strlen (users[cONNFD].WRITE_BUF), 0);                Users[connfd].write_buf=null;                Fds[i].events |=~pollout;            Fds[i].events |=pollin;    }}} free (users);    Close (LISTENFD); return 0;}

Poll functions for multi-user chat under Linux