Linux网络编程 使用socket实现简单服务器——多进程&多线程版本

1.多进程版

服务端

#include<stdio.h>
#include<arpa/inet.h>
#include<unistd.h>
#include<string.h>
#include<stdlib.h>
#include<signal.h>
#include<wait.h>
#include<errno.h>

void recyleChild(int ard) {
    while(1){
        int ret = waitpid(-1, NULL, WNOHANG);
        if(ret == -1){
            break;
        }else if(ret == 0){
            break;
        }else if(ret > 0){
            printf("子进程 %d 被回收\n",ret);
        }
    }
}

int main()  {

    struct sigaction act;
    act.sa_flags = 0;
    sigemptyset(&act.sa_mask);
    act.sa_handler = recyleChild;

    //注册信号捕捉
    sigaction(SIGCHLD, &act, NULL);
    //创建socket
    int lfd = socket(PF_INET, SOCK_STREAM, 0);
    if(lfd == -1){
        perror("socket");
        exit(-1);
    }

    //绑定
    struct sockaddr_in saddr;
    saddr.sin_family = AF_INET;
    saddr.sin_port = htons(9999);
    saddr.sin_addr.s_addr = INADDR_ANY;

    int optval = 1;
    setsockopt(lfd, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof(optval));
    //端口复用

    int ret = bind(lfd, (struct sockaddr *)&saddr, sizeof (saddr));
    if(ret ==-1){
        perror("bind");
        exit(-1);
    }

    //监听
    ret = listen(lfd, 128);
    if(ret == -1){
        perror("listen");
        exit(-1);
    }

    //不断循环等待客户端连接
    while(1){

        //接受链接
        struct sockaddr_in cliaddr;
        int len= sizeof(cliaddr);
        int cfd = accept(lfd, (struct sockaddr *)&cliaddr, &len);
        if(cfd == -1){
            if(errno == EINTR){
                continue;
            }
            perror("accept");
            exit(-1);
        }

        //每一个连接进来，创建一个子进程跟客户端通信
        pid_t pid = fork();
        if(pid == 0){
            //子进程
            //获取客户端信息
            char cliIp[16];
            inet_ntop(AF_INET, &cliaddr.sin_addr.s_addr, cliIp, sizeof(cliIp));
            unsigned short cliPort = ntohs(cliaddr.sin_port);
            printf("client ip is: %s, port is %d\n",cliIp, cliPort);

            //接受客户端发来的数据
            char recvBuf[1024]={0};
            while(1){

                int len =recv(cfd, &recvBuf, sizeof(recvBuf), 0);
                
                if(len==-1){
                    perror("recv");
                    exit(-1);
                }else if(len>0){
                    printf("recv client : %s\n",recvBuf);
                }else if(len == 0){
                    printf("client closed.....\n");
                    break;
                }

                write(cfd, recvBuf, strlen(recvBuf)+1);

            }

            close(cfd);
            exit(0);

        }

    }
    close(lfd);

    return 0;
}

2.多线程版

服务端

#include<stdio.h>
#include<arpa/inet.h>
#include<unistd.h>
#include<string.h>
#include<stdlib.h>
#include<pthread.h>

struct sockInfo {
    int fd; //通信的文件描述符
    pthread_t tid; //线程号
    struct sockaddr_in addr;
};

struct sockInfo sockinfos[128];

void * working(void * arg){
    //子线程和客户端通信  cfd 客户端的信息
    //获取客户端信息
    struct sockInfo * pinfo = (struct sockInfo *)arg;

    char cliIp[16];
    inet_ntop(AF_INET, &pinfo->addr.sin_addr.s_addr, cliIp, sizeof(cliIp));
    //将网络传输的二进制数值转化为成点分十进制的ip地址

    unsigned short cliPort = ntohs(pinfo->addr.sin_port);
    //将一个无符号短整形数从网络字节顺序转换为主机字节顺序。

    printf("client ip is: %s, port is %d\n",cliIp, cliPort);

    //接受客户端发来的数据
    char recvBuf[1024]={0};
    while(1){

        int len =read(pinfo->fd, &recvBuf, sizeof(recvBuf));
         
        if(len==-1){
            perror("read");
            exit(-1);
        }else if(len>0){
            printf("recv client : %s\n",recvBuf);
        }else if(len == 0){
            printf("client closed.....\n");
            break;
        }

        write(pinfo->fd, recvBuf, strlen(recvBuf)+1);
    }
    close(pinfo->fd);
    return NULL;
}

int main()  {

    //创建socket
    int lfd = socket(PF_INET, SOCK_STREAM, 0);
    if(lfd == -1){
        perror("socket");
        exit(-1);
    }

    //绑定
    struct sockaddr_in saddr;
    saddr.sin_family = AF_INET;
    saddr.sin_port = htons(9999);//端口号
    saddr.sin_addr.s_addr = INADDR_ANY;

    int ret = bind(lfd, (struct sockaddr *)&saddr, sizeof (saddr));
    if(ret ==-1){
        perror("bind");
        exit(-1);
    }

    //监听
    ret = listen(lfd, 128);
    if(ret == -1){
        perror("listen");
        exit(-1);
    }
    //初始化数据
    int max =sizeof(sockinfos) / sizeof(sockinfos[0]);
    for(int i=0;i<max;i++){
        bzero(&sockinfos[i], sizeof(sockinfos[i]));
        sockinfos[i].fd = -1;
        sockinfos[i].tid = -1;
    }

    //循环等待客户端连接
    while(1) {

         //接受链接
        struct sockaddr_in cliaddr;
        int len= sizeof(cliaddr);
        int cfd = accept(lfd, (struct sockaddr *)&cliaddr, &len);

        //创建子线程
        struct sockInfo * pinfo;
        for(int i=0;i<max;i++){
            //从这个数组中找到一个可用的sockInfo元素
            if(sockinfos[i].fd == -1){
                pinfo = &sockinfos[i];
                break;
            }
            if(i == max-1){
                sleep(1);
                i--;
            }
        }

        pinfo->fd=cfd;
        memcpy(&pinfo->addr, &cliaddr, len);

        pthread_create(&pinfo->tid, NULL, working, pinfo);

        pthread_detach(pinfo->tid);//线程分离，结束自己释放资源

    }
    close(lfd);

    return 0;
}

客户端

//TCP通信客户端

#include<stdio.h>
#include<arpa/inet.h>
#include<unistd.h>
#include<string.h>
#include<stdlib.h>

int main()  {

    //1.创建套接字
    int fd = socket(AF_INET, SOCK_STREAM, 0);
    if(fd == -1){
        perror("socket");
        exit(-1);
    }

    //2.连接服务器
    struct sockaddr_in serveraddr;
    serveraddr.sin_family = AF_INET;
    inet_pton(AF_INET, "192.168.110.135", &serveraddr.sin_addr.s_addr);
    serveraddr.sin_port = htons(9999);
    int ret = connect(fd, (struct sockaddr *)&serveraddr, sizeof(serveraddr));

    if(ret == -1){
        perror("connect");
        exit(-1);
    }

    char recvBuf[1024]={0};
    //3.通信
    int i=0;
    while(1){

        // char data[1024];
        fgets(recvBuf, sizeof(recvBuf), stdin);
        write(fd, recvBuf, strlen(recvBuf)+1);
        // i++;
        
        int len = read(fd, recvBuf, sizeof(recvBuf));
        if(len == -1){
            perror("read");
            exit(-1);
        }else if(len > 0){
            printf("recv serve : %s\n",recvBuf);
        }else if(len==0){
            printf("serve close...\n");
            break;
        }
        sleep(1);

    }
    //关闭
    close(fd); 

    return 0;
}

原文地址：http://www.cnblogs.com/wxk1213/p/16898118.html