c++下基于windows socket的多线程服务器(基于TCP协议)

　　之前用c++实现过基于windows socket的单线程TCP服务器(http://www.cnblogs.com/jzincnblogs/p/5170230.html)，今天实现了一个多线程的版本，可以接受多个客户端的请求，原理与之前的单线程版本相似，只是在多线程版本中主线程用于监测客户端请求，每当有新客户端请求连接，主线程便新开一个线程用户处理客户端的请求。代码如下：

　　头文件：

 #ifndef SERVER_H
 #define SERVER_H

 #include <Winsock2.h>
 #include <windows.h>

 #pragma comment (lib, "ws2_32.lib")

 #define IP_BUF_SIZE 129

 class Server
 {
 public:
     Server();
     ~Server();
     Server(const Server &) = delete;
     Server & operator=(const Server &) = delete;
     void WaitForClient();
 private:
     WORD winsock_ver;
     WSADATA wsa_data;
     SOCKET sock_svr;
     SOCKET sock_clt;
     HANDLE h_thread;
     SOCKADDR_IN addr_svr;
     SOCKADDR_IN addr_clt;
     int ret_val;
     int addr_len;
     char buf_ip[IP_BUF_SIZE];
 };

 #endif

　　函数定义：

 #include "server.h"
 #include <iostream>
 #include <WS2tcpip.h>

 using std::cerr;
 using std::cout;
 using std::endl;

 #define SERVER_PORT 5000
 #define MSG_BUF_SIZE 1024

 Server::Server()
 {
     cout << "Initializing server...\n";
     //
     winsock_ver = MAKEWORD(, );
     addr_len = sizeof(SOCKADDR_IN);
     addr_svr.sin_family = AF_INET;
     addr_svr.sin_port = ::htons(SERVER_PORT);
     addr_svr.sin_addr.S_un.S_addr = ADDR_ANY;
     memset(buf_ip, 0, IP_BUF_SIZE);
     //
     ret_val = ::WSAStartup(winsock_ver, &wsa_data);
     if (ret_val != )
     {
         cerr << "WSA failed to start up!Error code: " << ::WSAGetLastError() << "\n";
         system("pause");
         exit();
     }
     cout << "WSA started up successfully...\n";
     //
     sock_svr = ::socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
     if (sock_svr == INVALID_SOCKET)
     {
         cerr << "Failed to create server socket!Error code: " << ::WSAGetLastError() << "\n";
         ::WSACleanup();
         system("pause");
         exit();
     }
     cout << "Server socket created successfully...\n";
     //
     ret_val = ::bind(sock_svr, (SOCKADDR*)&addr_svr, addr_len);
     if (ret_val != )
     {
         cerr << "Failed to bind server socket!Error code: " << ::WSAGetLastError() << "\n";
         ::WSACleanup();
         system("pause");
         exit();
     }
     cout << "Server socket bound successfully...\n";
     //
     ret_val = ::listen(sock_svr, SOMAXCONN);
     if (ret_val == SOCKET_ERROR)
     {
         cerr << "Server socket failed to listen!Error code: " << ::WSAGetLastError() << "\n";
         ::WSACleanup();
         system("pause");
         exit();
     }
     cout << "Server socket started to listen...\n";
     //
     cout << "Server started successfully..." << endl;
 }

 Server::~Server()
 {
     ::closesocket(sock_svr);
     ::closesocket(sock_clt);
     ::WSACleanup();
     cout << "Socket closed..." << endl;
 }

 DWORD WINAPI CreateClientThread(LPVOID lpParameter);
 //
 void Server::WaitForClient()
 {
     while (true)
     {
         sock_clt = ::accept(sock_svr, (SOCKADDR*)&addr_clt, &addr_len);
         if (sock_clt == INVALID_SOCKET)
         {
             cerr << "Failed to accept client!Error code: " << ::WSAGetLastError() << "\n";
             ::WSACleanup();
             system("pause");
             exit();
         }
         ::InetNtop(addr_clt.sin_family, &addr_clt, buf_ip, IP_BUF_SIZE);
         cout << "A new client connected...IP address: " << buf_ip << ", port number: " << ::ntohs(addr_clt.sin_port) << endl;
         h_thread = ::CreateThread(nullptr, , CreateClientThread, (LPVOID)sock_clt, , nullptr);
         if (h_thread == NULL)
         {
             cerr << "Failed to create a new thread!Error code: " << ::WSAGetLastError() << "\n";
             ::WSACleanup();
             system("pause");
             exit();
         }
         ::CloseHandle(h_thread);
     }
 }

 DWORD WINAPI CreateClientThread(LPVOID lpParameter)
 {
     SOCKET sock_clt = (SOCKET)lpParameter;
     char buf_msg[MSG_BUF_SIZE];
     int ret_val = ;
     int snd_result = ;
     do
     {
         memset(buf_msg, 0, MSG_BUF_SIZE);
         ret_val = ::recv(sock_clt, buf_msg, MSG_BUF_SIZE, );
         if (ret_val > )
         {
             if (strcmp(buf_msg, "exit") == )
             {
                 cout << "Client requests to close the connection..." << endl;
                 break;
             }
             cout << "Message received: " << buf_msg << endl;
             snd_result = ::send(sock_clt, buf_msg, MSG_BUF_SIZE, );
             if (snd_result == SOCKET_ERROR)
             {
                 cerr << "Failed to send message to client!Error code: " << ::GetLastError() << "\n";
                 ::closesocket(sock_clt);
                 system("pause");
                 return ;
             }
         }
         else if (ret_val == )
         {
             cout << "connection closed..." << endl;
         }
         else
         {
             cerr << "Failed to receive message from client!Error code: " << ::GetLastError() << "\n";
             ::closesocket(sock_clt);
             system("pause");
             return ;
         }
     } while (ret_val > );
     //
     ret_val = ::shutdown(sock_clt, SD_SEND);
     if (ret_val == SOCKET_ERROR)
     {
         cerr << "Failed to shutdown the client socket!Error code: " << ::GetLastError() << "\n";
         ::closesocket(sock_clt);
         system("pause");
         return ;
     }
     return ;
 }

　　程序入口：

 #include "server.h"

 int main()
 {
     Server svr;
     svr.WaitForClient();
     system("pause");
     return ;
 }