linux socket编程（多线程）

深藏阁楼爱情的钟 2022-02-25 09:40 322阅读 0赞

1，客户端

#include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include <errno.h>
    
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <pthread.h>
    #include <netinet/in.h>
    #include <arpa/inet.h>
    
    /*
     强调：当客户端连接服务器时，服务器会产生一个新的文件描述符（套接字）与客户端交互，这个新的套接字不是服务器端的监听套接字
     套接字是全双工的，在一个网络管道中的两端，每端都可以进行读写操作。
     */
    
    typedef struct _recvmodel
    {
        int st;
        struct sockaddr_in * addr;
    } RecvModel;
    
    //send message
    void * send_thread(void *arg)
    {
        if (arg == NULL)
        {
            printf("param is not allow NULL!\n");
            return NULL;
        }
        int st = *(int *) arg;
        char buf[1024] = { 0 };
        while (1)
        {
            read(STDIN_FILENO, buf, sizeof(buf));
            if (send(st, buf, strlen(buf), 0) == -1)
            {
                printf("send failed ! error message %s\n", strerror(errno));
                return NULL;
            }
            memset(buf, 0, sizeof(buf));
        }
        return NULL;
    }
    
    //recv message
    void * recv_thread(void * arg)
    {
        if (arg == NULL)
        {
            printf("param is not allow NULL!\n");
            return NULL;
        }
        RecvModel * model = (RecvModel *) arg;
        int flag = 0;
        char buf[1024] = { 0 };
        while (1)
        {
            flag = recv(model->st, buf, sizeof(buf), 0);
            if (flag == 0)
            {
                printf("对方已经关闭连接！\n");
                return NULL;
            } else if (flag == -1)
            {
                printf("recv failed ! error message : %s\n", strerror(errno));
                return NULL;
            }
            printf("from %s:%s", inet_ntoa(model->addr->sin_addr), buf);
            memset(buf, 0, sizeof(buf));
        }
        return NULL;
    }
    
    int main(int arg, char *args[])
    {
        //打开socket
        int st = socket(AF_INET, SOCK_STREAM, 0);
        if (st == -1)
        {
            printf("open socket failed! error message:%s\n", strerror(errno));
            return -1;
        }
        //定义IP地址结构
        struct sockaddr_in addr;
        memset(&addr, 0, sizeof(addr));
        //设置TCP/IP连接
        addr.sin_family=AF_INET;
        //设置端口号
        addr.sin_port = htons(8080);
        //设置允许连接地址
        addr.sin_addr.s_addr = inet_addr("192.168.1.102");
        //connect server
        int numx = connect(st, (struct sockaddr *) &addr, sizeof(addr));
        if (numx == -1)
        {
            printf("connect server failed ! error message :%s\n", strerror(errno));
            goto END;
        }
    
        RecvModel model;
        model.st = st;
        model.addr = &addr;
        //开启多线程--线程1接收消息，线程2发送消息
        pthread_t thr1, thr2;
        if (pthread_create(&thr1, NULL, send_thread, &st) != 0)
        {
            printf("create thread failed ! \n");
            goto END;
        }
        if (pthread_create(&thr2, NULL, recv_thread, &model) != 0)
        {
            printf("create thread failed ! \n");
            goto END;
        }
        pthread_join(thr1, NULL);
        pthread_join(thr2, NULL);
        END: close(st);
        return 0;
    }

2，服务器端

//网络编程--服务端
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    #include <errno.h>
    
    #include <sys/types.h>
    #include <sys/socket.h>
    #include <pthread.h>
    #include <netinet/in.h>
    #include <arpa/inet.h>
    
    typedef struct _recvmodel
    {
        int st;
        struct sockaddr_in * addr;
    } RecvModel;
    
    //send message
    void * send_thread(void *arg)
    {
        if (arg == NULL)
        {
            printf("param is not allow NULL!\n");
            return NULL;
        }
        int st = *(int *) arg;
        char buf[1024] = { 0 };
        while (1)
        {
            read(STDIN_FILENO, buf, sizeof(buf));
            if (send(st, buf, strlen(buf), 0) == -1)
            {
                printf("send failed ! error message %s\n", strerror(errno));
                return NULL;
            }
            memset(buf, 0, sizeof(buf));
        }
        return NULL;
    }
    
    //recv message
    void * recv_thread(void * arg)
    {
        if (arg == NULL)
        {
            printf("param is not allow NULL!\n");
            return NULL;
        }
        RecvModel * model = (RecvModel *) arg;
        int flag = 0;
        char buf[1024] = { 0 };
        while (1)
        {
            flag = recv(model->st, buf, sizeof(buf), 0);
            if (flag == 0)
            {
                printf("对方已经关闭连接！\n");
                return NULL;
            } else if (flag == -1)
            {
                printf("recv failed ! error message : %s\n", strerror(errno));
                return NULL;
            }
            printf("from %s:%s", inet_ntoa(model->addr->sin_addr), buf);
            memset(buf, 0, sizeof(buf));
        }
        return NULL;
    }
    
    int main(int arg, char *args[])
    {
    
        //short port = atoi(args[1]);
        //打开socket
        int st = socket(AF_INET, SOCK_STREAM, 0);
        if (st == -1)
        {
            printf("open socket failed! error message:%s\n", strerror(errno));
            return -1;
        }
        //设置系统地址可重用
        int on = 1;
        if (setsockopt(st, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
        {
            printf("setsockpot failed ! error message %s\n", strerror(errno));
            goto END;
        }
        //定义IP地址结构
        struct sockaddr_in addr;
        memset(&addr, 0, sizeof(addr));
        //设置TCP/IP连接
        addr.sin_family = AF_INET;
        //设置端口号
        addr.sin_port = htons(8080);
        //设置允许连接地址
        addr.sin_addr.s_addr = htonl(INADDR_ANY);
        //bind ip
        if (bind(st, (struct sockaddr *) &addr, sizeof(addr)) == -1)
        {
            printf("bind ip failed ! error message :%s\n", strerror(errno));
            goto END;
        }
        //监听连接
        if (listen(st, 20) == -1)
        {
            printf("listen failed ! error message :%s\n", strerror(errno));
            goto END;
        }
        //接收客户端连接（阻塞）
        struct sockaddr_in client_addr;
        memset(&client_addr, 0, sizeof(client_addr));
        socklen_t client_addrlen = sizeof(client_addr);
        //强调：这里的client_addrlen并不是为了在函数中设置client_addrlen的值，而是通过client_addrlen的值来判断client_addr是一个什么类型的结构，
        //所以这里client_addrlen设置为0是错误的，必须是struct sockaddr_in这个结构的大小，不然返回值不正确
        int client_st = accept(st, (struct sockaddr *) &client_addr,
                &client_addrlen);
        if (client_st == -1)
        {
            printf("accept failed ! error message :%s\n", strerror(errno));
            goto END;
        }
        RecvModel model;
        model.st = client_st;
        model.addr = &client_addr;
        printf("accept by=%s\n",inet_ntoa(client_addr.sin_addr));
        //开启多线程--线程1接收消息，线程2发送消息
        pthread_t thr1, thr2;
        if (pthread_create(&thr1, NULL, send_thread, &client_st) != 0)
        {
            printf("create thread failed ! \n");
            goto END;
        }
        if (pthread_create(&thr2, NULL, recv_thread, &model) != 0)
        {
            printf("create thread failed ! \n");
            goto END;
        }
        pthread_join(thr1, NULL);
        pthread_join(thr2, NULL);
        //关闭客户端管道
        close(client_st);
        END: close(st);
        return 0;
    }