102.tcp实现多线程连接与群聊

• 协议之间的关系

• socket在哪

• socket是什么

　Socket是应用层与TCP/IP协议族通信的中间软件抽象层，它是一组接口。在设计模式中，Socket其实就是一个门面模式，它把复杂的TCP/IP协议族隐藏在Socket接口后面，对用户来说，一组简单的接口就是全部，让Socket去组织数据，以符合指定的协议。

　　门面模式，用自己的话说，就是系统对外界提供单一的接口，外部不需要了解内部的实现。

• socket编程的基本流程

tcp通信实现多线程连接与群聊

服务器端

• 定义端口以及本地ip地址

  #define port 9876
  #define ip_addr "192.168.1.102"

• 创建事件以及互斥量

  HANDLE event;//事件
  HANDLE mutex = NULL;

  event = CreateEvent(NULL, TRUE, FALSE, NULL);//第二个参数TRUE表示手动复位
      mutex = CreateMutex(NULL, FALSE, NULL);//互相排斥

• 接收连接

  //接受连接
  void recv_connect(void *p)
  {
      WSADATA WSA;//对比版本
  
      SOCKET client,sever;//客户端
  
      //本地地址信息,以及连接的客户端地址信息
      struct sockaddr_in localeaddr,clientaddr;
      int addrlength = 0;
      HANDLE hthread1 = NULL;//线程句柄
      HANDLE hthread2 = NULL;
      HANDLE hthread3 = NULL;
      int Ret = 0;
      char senbuf[256] = { 0 };
  
      //对比版本
      if (WSAStartup(MAKEWORD(2, 2), &WSA) != 0)
      {
          puts("版本不一致，通信失败");
          system("pause");
          return;
      }
      //创建通信
      sever = socket(AF_INET, SOCK_STREAM, 0);
      if (sever == INVALID_SOCKET)
      {
          puts("服务器创建失败");
          system("pause");
          return;
      }
      //设置服务器结构体信息
      localeaddr.sin_family = AF_INET;
      localeaddr.sin_addr.s_addr = inet_addr(ip_addr);
      localeaddr.sin_port = htons(port);
      memset(localeaddr.sin_zero, 0x00, 8);//清零
      //与socket绑定
      Ret = bind(sever, (struct sockaddr*)&localeaddr, sizeof(localeaddr));
      if (Ret != 0)
      {
          puts("绑定失败");
          system("pause");
          return;
      }
      Ret = listen(sever, 5);
      if (Ret != 0)
      {
          puts("监听失败");
          system("pause");
          return;
      }
      puts("服务器启动");
  
      while (1)
      {
          addrlength = sizeof(clientaddr);//获取长度
          //接受客户端连接,信息存放在clientaddr中
          client = accept(sever, (struct sockaddr*) &clientaddr, &addrlength);
          if (client == INVALID_SOCKET)
          {
              puts("接收失败");
              system("pause");
              return;
          }
          printf("
  客户端连接%s  端口号:%d
  ", inet_ntoa(clientaddr.sin_addr), clientaddr.sin_port);
          //创建写的线程
          hthread3 = CreateThread(NULL, 0, clientthreadwrite, (void*)client, 0, NULL);
      }
  
      //关闭socket
      closesocket(sever);
      closesocket(client);
      WSACleanup();
  }

• 向客户端发送消息的多线程函数

  //创建线程向客户端发送消息
  DWORD WINAPI clientthreadwrite(void *p)
  {
      SOCKET client = (SOCKET)p;//数指针类型转换
      int Ret = 0;
  
      while (1)
      {
          WaitForSingleObject(event, INFINITE);//等待事件
          WaitForSingleObject(mutex, INFINITE);
          
          if (strlen(sendbuf) != 0)
          {
              //发送信息
              Ret = send(client, sendbuf, strlen(sendbuf), 0);
          }
          ReleaseMutex(mutex);
          ResetEvent(event);//手动复位
      }
  }

• 从客户端接收消息的多线程函数

  DWORD WINAPI clientthreadread(void *p)
  {
      //数指针类型转换
      SOCKET client = (SOCKET)p;
      int Ret = 0;
      char receivebuf[256];
  
      while (1)
      {
          //清零
          memset(receivebuf, 0, 256);
          //读取
          Ret = recv(client, receivebuf, 256, 0);
          if (Ret == SOCKET_ERROR)
          {
              puts("客户端send失败");
              break;
          }
          printf("
  收到%s,", receivebuf);    
          //进入临界区
          WaitForSingleObject(mutex, INFINITE);
          memset(sendbuf, 0, 256);
          //全局变量，锁定
          strcpy(sendbuf, receivebuf);
          ReleaseMutex(mutex);
          //通知
          SetEvent(event);
      }
      return 0;
  }

  　　
• main函数

  void main()
  {
      event = CreateEvent(NULL, TRUE, FALSE, NULL);//第二个参数TRUE表示手动复位
      mutex = CreateMutex(NULL, FALSE, NULL);//互相排斥
  
      _beginthread(recv_connect, 0, NULL);
  
      Sleep(100);
      while (1)
      {
          printf("请输入要发送的信息:");
          scanf("%s", sendbuf);
          SetEvent(event);
      }
      system("pause");
  }

客户端

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
#include <winsock.h>
#pragma comment(lib,"ws2_32.lib")

//定义端口号
#define port 9876
//要连接的ip地址
#define ip_addr "192.168.1.102"


void main()
{
    //对比版本
    WSADATA WSA;
    //客户端套接字
    SOCKET client;
    //服务器信息
    struct sockaddr_in severaddr;
    //线程句柄
    HANDLE hthread = NULL;
    //保存连接信息
    int Ret = 0;
    char senbuf[256] = { 0 };

    if (WSAStartup(MAKEWORD(2,2),&WSA)!=0)
    {
        puts("版本不一致，通信失败");
        system("pause");
        return;
    }
    //创建socket
    client = socket(AF_INET, SOCK_STREAM, 0);
    if (client == INVALID_SOCKET)
    {
        puts("客户端创建失败");
        system("pause");

    }
    //设置服务器信息
    severaddr.sin_family = AF_INET;
    //设置地址
    severaddr.sin_addr.s_addr = inet_addr(ip_addr);
    //端口
    severaddr.sin_port = htons(port);
    //清空
    memset(severaddr.sin_zero, 0x00, 8);

    //连接
    Ret = connect(client, (struct sockaddr*) &severaddr, sizeof(severaddr));
    if (Ret!=0)
    {
        puts("客户端链接失败");
        system("pause");
    }
    while (1)
    {
        //printf("请输入向服务器发送的消息:");
        //scanf("%s", senbuf);//输入
        //Ret = send(client, senbuf, strlen(senbuf), 0);//发送
        //if (Ret==SOCKET_ERROR)
        //{
        //    puts("客户端send失败");
        //    system("pause");
        //}
        char receivebuf[256];
        memset(receivebuf, 0, 256);//清零
        Ret = recv(client, receivebuf, 256, 0);
        printf("收到客户端发送的消息:%s
", receivebuf);
    }

    closesocket(client);
    WSACleanup();
}