实现TCP通信客户端和服务端

最后更新：2023-08-29

一、Server端实现

Go语言C语言

//Server.go
package main

import (
    "fmt"
    "net"
    "os"
)

func main(){
    //服务端在本机8888端口建立tcp监听
    listener,err :=net.Listen("tcp","127.0.0.1:8888")
    ServerHandleError(err,"net.listen")

    for {
        //循环接入所有客户端得到专线连接
        conn,e := listener.Accept()
        ServerHandleError(e,"listener.accept")
        //开辟独立协程与该客聊天
        go ChatWith(conn)
    }
}

func ServerHandleError(err error,when string) {
    if err != nil {
        fmt.Println(err, when)
        os.Exit(1)
    }
}

//在conn网络专线中与客户端对话
func ChatWith(conn net.Conn){
    //创建消息缓冲区
    buffer := make([]byte, 1024)
    for {
        ///---一个完整的消息回合
        //读取客户端发来的消息放入缓冲区
        n,err := conn.Read(buffer)
        ServerHandleError(err,"conn.read buffer")

        //转化为字符串输出
        clientMsg := string(buffer[0:n])
        fmt.Printf("收到消息",conn.RemoteAddr(),clientMsg)

        //回复客户端消息
        if clientMsg != "im off" {
            conn.Write([]byte("已读:"+clientMsg))
        } else {
            conn.Write([]byte("bye"))
            break
        }
    }
    conn.Close()
    fmt.Printf("客户端断开连接",conn.RemoteAddr())
}

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#define _PORT_ 9999
#define _BACKLOG_ 10

int main()
{
    int sock=socket(AF_INET,SOCK_STREAM,0);
    if(sock<0)
    {
        printf("socket()\n");
    }
    struct sockaddr_in server_socket;
    struct sockaddr_in socket;
    bzero(&server_socket,sizeof(server_socket));
    server_socket.sin_family=AF_INET;
    server_socket.sin_addr.s_addr=htonl(INADDR_ANY);
    server_socket.sin_port=htons(_PORT_);
    if(bind(sock,(struct sockaddr*)&server_socket,sizeof(struct sockaddr_in))<0)
    {
        printf("bind()\n");
        close(sock);
        return 1;
    }
    if(listen(sock,_BACKLOG_)<0)
    {
        printf("listen()\n");
        close(sock);
        return 2;
    }
    printf("success\n");
    for(;;)
    {
        socklen_t len=0;
        int client_sock=accept(sock,(struct sockaddr*)&socket,&len);
        if(client_sock<0)
        {
            printf("accept()\n");
            return 3;
        }
        char buf_ip[INET_ADDRSTRLEN];
        memset(buf_ip,'\0',sizeof(buf_ip));
        inet_ntop(AF_INET,&socket.sin_addr,buf_ip,sizeof(buf_ip));
        printf("get connect\n");
        
        while(1)
        {
            char buf[1024];
            memset(buf,'\0',sizeof(buf));
            read(client_sock,buf,sizeof(buf));
            
            printf("client:# %s\n",buf);
            printf("server:$ ");
            
            memset(buf,'\0',sizeof(buf));
            fgets(buf,sizeof(buf),stdin);
            buf[strlen(buf)-1]='\0';
            if(strncasecmp(buf,"quit",4)==0)
            {
                printf("quit\n");
                break;
            }
            write(client_sock,buf,strlen(buf)+1);
            printf("wait...\n");
        }
        close(client_sock);
    }
    close(sock);
    return 0;
}

二、Client端实现

Go语言C语言

//Client.go
package main

import (
    "bufio"
    "fmt"
    "net"
    "os"
)

func ClientHandleError(err error, when string){
    if err != nil {
        fmt.Println(err, when)
        os.Exit(1)
    }
}

func main(){
    //拨号远程地址，简历tcp连接
    conn, err := net.Dial("tcp","127.0.0.1:8888")
    ClientHandleError(err, "client conn error")

    //预先准备消息缓冲区
    buffer := make([]byte,1024)

    //准备命令行标准输入
    reader := bufio.NewReader(os.Stdin)
    
    for {
        lineBytes,_,_ := reader.ReadLine()
        conn.Write(lineBytes)
        n,err := conn.Read(buffer)
        ClientHandleError(err, "client read error")
        
        serverMsg := string(buffer[0:n])
        fmt.Printf("服务端msg",serverMsg)
        if serverMsg == "bye" {
            break
        }
    }
}

#include <strings.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <netinet/ip.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <pthread.h>

void *recv_data(void *arg)
{
    int sockfd = *(int *)arg;
    char s[64] = {0};
    while(1)
    {
        int ret = read(sockfd, s, 64);
        if(ret < 0)
        {
            perror("read");
            return NULL;
        }
        printf("%s\n", s);
        memset(s, 0, 64);
    }
}

int main(int argc, char *argv[])
{
    int sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if(sockfd == -1)
    {
        perror("socket");
        return -1;
    }
    
    pthread_t pid;
    pthread_create(&pid, NULL, recv_data, (void *)&sockfd);
    pthread_detach(pid);

    struct sockaddr_in ser;
    ser.sin_family = AF_INET;
    ser.sin_port = htons(11111);
    //ser.sin_addr.s_addr = inet_addr("0.0.0.0");
    ser.sin_addr.s_addr = htonl(INADDR_ANY);
    
    int ret = connect(sockfd, (struct sockaddr *)&ser, sizeof(ser));
    if(ret == -1)
    {
        perror("connect");
        return -1;
    }
    
    char buf[64];
    while(1)
    {
        fgets(buf, 64, stdin);
        buf[strlen(buf)-1] = '\0';
        write(sockfd, buf, 64);
        
        if(strcmp(buf, "time") == 0)
        {
            char data[64];
            read(sockfd, data, 64);
            printf(">>:%s\n", data);
            memset(buf, 0, 64);
            memset(data, 0, 64); 
        } else if(strncmp(buf, "get", 3) == 0) {
            char str[64];
            while(read(sockfd, str, 64) != 0) {
                if(strcmp(str, "over") == 0) {
                    memset(str, 0, 64);        
                    break;
                }
                printf(">>:%s\n", str);
                memset(buf, 0, 64);
                memset(str, 0, 64); 
            }
        } else {	
            char arr[64] = {0};
            read(sockfd, arr, 64);
            printf(">>:%s\n", arr);
            memset(buf, 0, 64);
            memset(arr, 0, 64); 
        }
    }
    close(sockfd);
    return 0;
}