网络编程(6)单进程多线程并发服务器实现-CFANZ编程社区

会占用大量的资源而多线程方式都在一个进程内，就无需占用这些资源，但同步也是个问题，而且一个线程挂了，可能会影响到进程中的其它线程。

多线程并发的原理就是当accept 成功连接一个客户端后，把与这个客户端的交互丢到新线程去处理它。

服务端代码:

/*************************************************
Author: xiongchuanliang
Description: 单进程多线程服务端代码
编译命令:
Linux:
g++ -o tcpserver_thread tcpserver_thread.cpp -m64 -I./common -lpthread
**************************************************/

// 服务端代码
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <pthread.h>
#include <string.h>
#include <sys/stat.h>
#include <time.h>

#include "initsock.h"
#include "common.h"


CInitSock initSock;

//客户端Socket信息结构体
typedef struct _client_info{        
   int    fd;              //客户端socket描述符
   struct sockaddr_in addr;    //客户端地址信息结构体    
   time_t lastseconds;        //可依这个计算空闲时间,空闲太长的连接可以关闭。
} client_info; 

void *TestSocket(void *cinfo);

int main(int argc, char* argv[])
{
   struct _client_info *client_info = NULL;
   
   //创建套接字
   SOCKET sListen = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
   if(sListen == INVALID_SOCKET)
   {
      PrintError("socket() failed.\n");
      exit(EXIT_FAILURE);
   }

   //绑定本地IP和端口到套接字
   struct sockaddr_in server_addr;
   server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(SERVPORT); //大于1024且小于65535
   server_addr.sin_addr.s_addr = INADDR_ANY;
   bzero(&(server_addr.sin_zero),8);

   //SO_REUSEADDR : 使bind函数能允许地址立即重用
   int on = 1;
   setsockopt( sListen, SOL_SOCKET, SO_REUSEADDR, (const char*)&on, sizeof(on) );

   if(bind(sListen,(struct sockaddr *)&server_addr,sizeof(struct sockaddr)) == SOCKET_ERROR)
    {
      PrintError("bind() failed.");
      exit(EXIT_FAILURE);
    }

    //开始监听
    if(listen(sListen, BACKLOG) == SOCKET_ERROR)
    {  
      PrintError("sListen() failed.");
        exit(EXIT_FAILURE);
    }

   struct sockaddr_in remoteAddr = {0};
   socklen_t nAddrlen = sizeof(struct sockaddr_in);
   pthread_t tpid;

   //循环接收数据
   while(1){   
      SOCKET sClient;            
      printf("等待客户端连接中...\n");   
      sClient = accept(sListen,(struct sockaddr *)&remoteAddr, &nAddrlen);     
      if(sClient == INVALID_SOCKET)
      {
         PrintError("accept() failed.");
         continue;
      }
      printf("接收到一个客户端连接:%s \n",inet_ntoa(remoteAddr.sin_addr));

      //复制连接
      client_info = (struct _client_info *)malloc(sizeof(struct _client_info));
      client_info->fd = sClient; 
      memcpy((void *)&client_info->addr,&remoteAddr,sizeof(remoteAddr));
      client_info->lastseconds = time(NULL);
      //在线程中处理
      if( pthread_create(&tpid,NULL,&TestSocket,(void *)client_info) != 0 ) 
       {
          PrintError("pthread_create() failed.");
          exit(EXIT_FAILURE);
       }

   }// end while

   
   exit(EXIT_SUCCESS);
}


void *TestSocket(void *cinfo)
{
   pthread_t tid; 
   char sendData[100] = {0};
   struct _client_info *client_info = (struct _client_info *)cinfo;
   tid = pthread_self();

   SOCKET sClient = client_info->fd;   
   char recvData[MAXDATASIZE]={0};
   //接收数据
   int recvbytes = recv(sClient, recvData, MAXDATASIZE, 0);        
   if( recvbytes == 0)
   {
      printf("recv() no data!\n");
   }else if( recvbytes < 0)
   {
      PrintError("recv() failed");
   }else if(recvbytes > 0)
   {            
      recvData[recvbytes]='\0';
      printf("service thread id=%lu \n收到信息:%s\n",tid,recvData);         
   
      //发送数据到客户端
      //char * sendData = "客户端，你好啊!\n";   
      snprintf(sendData,100,"service thread id=%lu \n%s\n",tid, recvData); 
      send(sClient, sendData, strlen(sendData), 0);
   }
  
   //关闭子进程连接的套接字  
   close(sClient);

   free(cinfo);
   pthread_exit(NULL);
}