Linux C 网络编程之路—— TCP client、tcp server

common.h头文件

c 复制代码

#ifndef __COMMON__H__
#define __COMMON__H__

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#define LOG_SOFT(fmt,...) printf("%s,%d:" fmt,__FUNCTION__,__LINE__,##__VA_ARGS__)

#define SERVER_IP "172.23.10.84"
#define SERVER_PORT 8600

#define LOG_SOFT(fmt,...) printf("%s,%d:" fmt,__FUNCTION__,__LINE__,##__VA_ARGS__)
#define LOG_SOFT_ERRNO(fmt,...) printf("errno:%d,%s,%s,%d:" fmt,errno,strerror(errno),__FUNCTION__,__LINE__,##__VA_ARGS__)


#endif

tcp_client.c

c 复制代码

#include "common.h"


int main()
{   
    char buf[1024] = {"hello,word"};
    int ret = 0 ;
    //IPV4,TCP,0默认协议
    int socket_fd = socket(AF_INET,SOCK_STREAM | SOCK_CLOEXEC ,0);
    if(socket_fd == -1)
    {
        LOG_SOFT("socket faild:%d,%s",errno,strerror(errno));
       
        return -1;
    }

    struct sockaddr_in server_addr;
    int addr_len = 0;
    {
        memset(&server_addr,0,sizeof(struct sockaddr_in));
        server_addr.sin_family = AF_INET;
        server_addr.sin_port = htons(SERVER_PORT);
        server_addr.sin_addr.s_addr = inet_addr(SERVER_IP);
        addr_len = sizeof(server_addr);
    }

    {
        ret = connect(socket_fd,(struct sockaddr*)&server_addr,addr_len);
        if(ret < 0)
        {
            LOG_SOFT("connect failed ,errno:%d,%s\n",errno,stderr);
        
        }
    }

    while (1)
    {
        memcpy(buf,"hello,word",sizeof("hello,word"));
        ret = write(socket_fd, buf, strlen(buf));
        LOG_SOFT("send data ret:%d, %s \n", ret, buf);

        ret = read(socket_fd, buf, sizeof(buf));
        if (ret > 0)
        {
            LOG_SOFT("recv data %s\n", buf);
        }
        else if (ret < 0)
        {
            LOG_SOFT("recv errno:%d,%s", errno, strerror(errno));
        }
        else
        {
            LOG_SOFT("ret == 0,fd:%d\n", socket_fd);
        }
    }

    close(socket_fd);

    return 0;
}

tcp_server

c 复制代码

#include "common.h"

int main()
{

    int client_fd = -1;
    int socket_fd = socket(AF_INET,SOCK_STREAM,0);

    if(socket_fd < 0)
    {
        LOG_SOFT_ERRNO("socket faild\n");
        goto on_errno;
    }
    int value = 1;
    //SO_REUSEADDR: 当服务进程崩溃重启或者主动重启时，会进入time_wait，如果不使用该选项，会导致服务无法启动
    
    if(setsockopt(socket_fd,SOL_SOCKET,SO_REUSEADDR,&value,sizeof(value)) < 0)
    {
        LOG_SOFT_ERRNO("setsockopt faild\n");
        goto on_errno;
    }
    struct sockaddr_in server_addr;
    memset(&server_addr,0,sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(SERVER_PORT);
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    int addr_len = sizeof(server_addr);
    int ret = bind(socket_fd,(const struct sockaddr*)&server_addr,addr_len);
    if(ret < 0)
    {
        LOG_SOFT_ERRNO("bind faild\n");
        goto on_errno;
    }

    ret = listen(socket_fd,5);
    if(ret < 0)
    {
        LOG_SOFT_ERRNO("listen faild\n");
        goto on_errno;
    }

    struct sockaddr_in client_addr;
    client_fd = accept(socket_fd,(struct sockaddr*)&client_addr,&addr_len);
    if(client_fd < 0)
    {
        LOG_SOFT_ERRNO("accept faild %d\n",client_fd);
        goto on_errno;
    }
    // sleep(2);

    char buf[1024] = {0};
    while (1)
    {
        int read_len = read(client_fd, buf, 1024);
        if (read_len > 0)
        {
            LOG_SOFT("recv data %s\n", buf);
            write(client_fd, "server", sizeof("server"));
            // break;
        }
        else if (read_len < 0)
        {
            LOG_SOFT("recv errno:%d,%s", errno, strerror(errno));
            // break;
        }
        else
        {
            LOG_SOFT("ret == 0,fd:%d\n", socket_fd);
            // continue;
        }
    }

    close(socket_fd);
    close(client_fd);


    return 0;

    on_errno:
        close(socket_fd);
        client_fd == -1 ?  : close(client_fd);
       
        return -1;
}