实现服务器端的多线程SOCKET Server(独立监听线程)

实现服务器端的多线程SOCKET Server
C++/VC

想要实现的功能：在服务器端有一个控制台程序（或者Windows服务），与多个客户端程序通讯，其中主线程有一个socket绑定在一个固定端口上，负责监听客户端的Socket信息。每当启动一个客户端程序，客户端发送来一个socket连接请求，server端就新开启一个线程，并在其中创建一个socket与该客户端的socket通讯，直到客户端程序关闭，结束该线程。主线程中的socket在应用程序退出时关闭。

这里是Server端代码的简单示意，展示了如何创建多线程的Socket Server。

#include "StdAfx.h"

#include <stdio.h>

DWORD WINAPI AnswerThread(LPVOID lparam)

{

SOCKET ClientSocket=(SOCKET)(LPVOID)lparam;

int bytesRecv;

char sendbuf[32]="";

char recvbuf[32]="";

while(1)

{

bytesRecv=SOCKET_ERROR;

for(int i=0;i<(int)strlen(recvbuf);i++)

{ recvbuf[i]=´\0´; }

while(bytesRecv==SOCKET_ERROR)

{ //Receiving Data

bytesRecv=recv(ClientSocket,recvbuf,32,0);

}

//Write your processing code here

send(ClientSocket,recvbuf,strlen(recvbuf),0);

printf("%s\n",recvbuf);

}

return 0;

}

int main(int argc,char* argv[])

{

//initialize Winsock

WSADATA wsaData;

int iRet=WSAStartup(MAKEWORD(2,2),&wsaData);

if(iRet!=NO_ERROR)

printf("Error at WSAStartup()\n");

//create a
socket

SOCKET m_socket;

m_socket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

if(m_socket==INVALID_SOCKET)

{

printf("Error at
socket():%ld\n",WSAGetLastError());

WSACleanup();

return 0;

}

//bind a
socket

sockaddr_in service;

service.sin_family=AF_INET;

service.sin_addr.s_addr=inet_addr("172.16.3.250");

service.sin_port=htons(2501);

if(bind(m_socket,(SOCKADDR*)&service,sizeof(service))==SOCKET_ERROR)

{

printf("bind() failed.\n");

closesocket(m_socket);

return 0;

}

else

printf("bind OK.\n");

//listen on a
socket

if(listen(m_socket,20)==SOCKET_ERROR)

printf("Error listening on
socket.\n");

else

printf("listening ok.\n");

//accept a connection

SOCKET AcceptSocket;

printf("Waiting for a client to connect...\n");

while(1)

{

AcceptSocket=SOCKET_ERROR;

while(AcceptSocket==SOCKET_ERROR)

{

AcceptSocket=accept(m_socket,NULL,NULL);

}

printf("Client Connected.\n");

DWORD dwThreadId;

HANDLE hThread;

hThread=CreateThread(NULL,NULL, AnswerThread,

(LPVOID)AcceptSocket,0,&dwThreadId);

if(hThread==NULL)

{

printf("CreatThread AnswerThread() failed.\n");

}

else

{

printf("CreateThread OK.\n");

}

}

return 0;

}

Socket的客户端程序就很简单了，可以使用VB拖一个WinSock控件到Form中，然后连接服务器的Socket并发送数据就行了。

最好不要在主进程监听，会造成堵塞，CPU占用100%