c_cpp client_tcp_epoll.c

Posted 2021-05-14

/*================================================
* Author         : Junjie Huang
* Email          : [e-mail]
* Last modified  : 2016-02-15 14:39
* Filename       : client_tcp_epoll.c
* Description    : TCP客户端，用epoll实现IO多路复用
================================================*/
#include "func.h"

int main (int argc, char const* argv[])
{
    if(argc != 3){
        printf("args error!\n");
        return -1;
    }
    int sfd = socket(AF_INET, SOCK_STREAM, 0);
    if(-1 == sfd){
        perror("socket");
        return -1;
    }
    struct sockaddr_in server_addr;
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr(argv[1]);
    server_addr.sin_port = htons(atoi(argv[2]));
    int ret = connect(sfd, (struct sockaddr *)&server_addr, sizeof(struct sockaddr));
    if(-1 == ret){
        perror("connect");
        close(sfd);
        return -1;
    }
    printf("connect server success!\n");
    char buf[128];
    int epfd = epoll_create(1);
    struct epoll_event epev, epevs[2];
    //注册sfd
    epev.events = EPOLLIN;
    epev.data.fd = sfd;
    ret = epoll_ctl(epfd, EPOLL_CTL_ADD, sfd, &epev);
    if(-1 == ret){
        perror("epoll_ctl1");
        close(sfd);
        close(epfd);
        return -1;
    }
    //注册STDIN_FILENO
    epev.events = EPOLLIN;
    epev.data.fd = STDIN_FILENO;
    ret = epoll_ctl(epfd, EPOLL_CTL_ADD, STDIN_FILENO, &epev);
    if(-1 == ret){
        perror("epoll_ctl1");
        close(sfd);
        close(epfd);
        return -1;
    }
    int i;
    while(1){
        bzero(epevs, sizeof(epevs));
        ret = epoll_wait(epfd, epevs, 2, -1);
        if(ret > 0){
            for(i = 0; i < ret; i++){
                if(epevs[i].data.fd == STDIN_FILENO && epevs[i].events == EPOLLIN){
                    bzero(buf, sizeof(buf));
                    read(STDIN_FILENO, buf, sizeof(buf));
                    ret = send(sfd, buf, strlen(buf) - 1, 0);
                    if(-1 == ret){
                        perror("send");
                        close(sfd);
                        close(epfd);
                        return -1;
                    }
                }
                if(epevs[i].data.fd == sfd && epevs[i].events == EPOLLIN){
                    bzero(buf, sizeof(buf));
                    ret = recv(sfd, buf, sizeof(buf), 0);
                    if(ret > 0){
                        printf("%s\n", buf);
                    }
                }
            }
        }
    }
    close(sfd);
    close(epfd);
    return 0;
}