Linux Socket Talkclient Talkserver example

Tag: input int string cannot main char* argv ready hint

Cleint:

#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 int main (int argc, C        har* argv[]) {if (argc <= 2) {printf ("Usage:%s ip_address port_number\n", basename (Argv[0]));    return 1;    } const char* IP = argv[1];     int port = atoi (argv[2]);    struct sockaddr_in server_address;    Bzero (&server_address, sizeof (server_address));    server_address.sin_family = af_inet;    Inet_pton (Af_inet, IP, &server_address.sin_addr);     Server_address.sin_port = htons (port);    int SOCKFD = socket (pf_inet, sock_stream, 0);    ASSERT (sockfd >= 0);    Here's use block mode connect socket, there'll be minutes timeout if failed. if (Connect (sockfd, struct sockaddr*) &server_address, sizeof (server_address)) < 0) {printf ("Connection failed\n");        Close (SOCKFD);    return 1;    } POLLFD fds[2]; FDS[0].FD = 0;    stdin fds[0].events = Pollin;    fds[0].revents = 0;    FDS[1].FD = SOCKFD;    Why don ' t concern about Pollout event? fds[1].events = Pollin | Pollrdhup; Concern Read & Hangup event fds[1].events = Pollin | Pollrdhup |    Pollout;    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  }//connection is hang-up by peer if (fds[1].revents & pollrdhup) {printf ("Server            Close the connection\n ");        Break }//have data from server to read else if (Fds[1].revents & Pollin) {memset(Read_buf, ' buffer_size ');            Recv (FDS[1].FD, Read_buf, buffer_size-1, 0);        printf ("Recv data from server:%s\n", read_buf); } else if (Fds[1].revents & pollout) {//always writable, would print so much a message, so Comm        ENT It//printf ("Connection got Pollout event, it is writable now.\n");  } if (Fds[0].revents & Pollin)//user input--stdin has data to read {//stdin- PIPEFD[1] ret = splice (0, NULL, pipefd[1], NULL, 32768, Splice_f_more |            Splice_f_move); PIPEFD[1]-pipefd[0]-SOCKFD 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 65535 struct client_data{sockaddr_in address;    char* Write_buf;    Char buf[buffer_size]; Client_data (): Write_buf (0) {}};    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 (int argc, char* argv[]) {if (argc <= 2) {printf ("Usage:%s ip_address port_number\n", Basena        Me (argv[0]);    return 1;    } const char* IP = argv[1];     int port = atoi (argv[2]);    int ret = 0;    struct SOCKADDR_IN address; Bzero (&address, sizeof(address));    address.sin_family = af_inet;    Inet_pton (Af_inet, IP, &address.sin_addr);     Address.sin_port = htons (port);    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);     Backlog=5 assert (Ret! =-1);    client_data* users = new Client_data[fd_limit]; POLLFD fds[user_limit+1];    1 Listen sock FD + 5 user sock fd int user_counter = 0;        for (int i = 1; I <= user_limit; ++i) {fds[i].fd =-1;    fds[i].events = 0;    } FDS[0].FD = LISTENFD; fds[0].events = Pollin | Pollerr;     Read & Error Event fds[0].revents = 0;        while (1) {ret = poll (FDS, user_counter+1,-1);            if (Ret < 0) {printf ("poll failure\n");        Break } for (int i = 0; i < user_counter+1; ++i) {//CLIENT call connect to this server if ((FDS[I].FD = = LISTENFD) && (fds[i].revents & Pollin))                {struct sockaddr_in client_address;                socklen_t client_addrlength = sizeof (client_address);                LISTENFD is block mode by default, but use poll we know the event is ready, accept'll return right now                int CONNFD = Accept (LISTENFD, (struct sockaddr*) &client_address, &client_addrlength);                    if (CONNFD < 0) {printf ("Accept errno is:%d\n", errno);                Continue } if (User_counter >= user_limit) {Const char* info = "Too many use                    RS, so close this connfd returned by accept.\n ";                    printf ("%s", info);                    Send (CONNFD, info, strlen (info), 0);                    Close (CONNFD);                Continue  }              user_counter++;                users[connfd].address = client_address;  Setnonblocking (CONNFD);                CONNFD is Nonblock mode fds[user_counter].fd = CONNFD; fds[user_counter].events = Pollin | Pollrdhup |                pollerr;//concern about Read & Hanguo & Error event at start fds[user_counter].revents = 0;            printf ("comes a new user, now has%d users\n", user_counter);            } else if (Fds[i].revents & Pollerr)//fds[i] has error!                {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) {p                rintf ("Get socket Option failed\n"); } else printf ("%d got an ERror%s\n ", FDS[I].FD, errors);            Continue } else if (Fds[i].revents & Pollrdhup)//fds[i] was hang up by peer {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");  }//got Readable event else if (Fds[i].revents & pollin) {int CONNFD                = FDS[I].FD;                memset (users[connfd].buf, ' buffer_size ');                ret = recv (CONNFD, Users[connfd].buf, buffer_size-1, 0);                printf ("Get%d bytes of client data:%s from connection:%d\n", ret, Users[connfd].buf, CONNFD); if (Ret < 0)//has error {//nonblock socket, the Read function returns an error eagain, prompting your application to now have no data to read please slightly                    And then try again. If it is a eagain error we just IGnore This error and wait for next Pollin event if (errno! = Eagain) {                        Close (CONNFD);                        USERS[FDS[I].FD] = USERS[FDS[USER_COUNTER].FD];                        Fds[i] = Fds[user_counter];                        i--;                        user_counter--;                    printf ("recv data from a client-ran into error, a client maybe left\n");                }}//if the connection has been gracefully closed and the return value is zero.                    else if (ret = = 0) {//printf ("code should not come to here\n");                    printf ("recv function return 0 indicates the client has gracefully closed and exit.\n");                Need to remove it from FDS??                    } else//server send the data recv from a client to all other clients { for (int j = 1; J <=User_counter;                            ++J) {if (fds[j].fd = = CONNFD) { Continue Don ' t send to self}//Other client's socket is no longer readable at the moment (current Client continues to send multiple messages, these messages will be blocked in the socket Sendbuffer),//To be set to only write!                        Because if you can read it again, if the client sends multiple messages consecutively, the other client will miss the following message!                        Fds[j].events |= ~pollin;                        Fds[j].events |= pollout;                    Users[fds[j].fd].write_buf = Users[connfd].buf;                }}} and Else if (Fds[i].revents & pollout)//got writable Event {                int connfd = FDS[I].FD;                if (! Users[connfd].write_buf) {continue;//no data Send to this client                } ret = Send (CONNFD, Users[connfd].write_buf, strlen (USERS[CONNFD].WRITE_BUF), 0); USers[connfd].write_buf = NULL;                Reset back fds[i].events |= ~pollout;            Fds[i].events |= Pollin;    }}} Delete [] users;    Close (LISTENFD); return 0;}

　　

Linux Socket Talkclient Talkserver example