简易的命令行聊天室程序（Winsock，服务器&客户端）

代码中使用WinSock2函数库，设计并实现了简单的聊天室功能。该程序为命令行程序。对于服务器和客户端，需要：

1. 服务器：创建监听套接字，并按本地主机绑定；主线程监听并接受来自客户端的请求，并为该客户端创建单独线程；接收与发送消息的事务放在同各客户端的单独线程中处理。
2. 客户端：创建套接字，并对服务器发起连接；主线程始终处于发送消息的状态；副线程用于不断从服务器接收来自其他客户端的消息。

实验代码及部分说明如下：

1. 服务器（Server.cpp）

#include <WinSock2.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include<vector>

using namespace std;

#define DEFAULT_PORT 7321

#define BUF_SIZE 1024

typedef struct{

SOCKET info_socket_rev;

sockaddr_in info_addr_rev;

} info2thread;

char szMessage[BUF_SIZE];

std::vector<SOCKET>  vClientSockets;  //用于保存连接中的Client套接字

DWORD WINAPI ThreadProc(PVOID pParam) ;

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

WSADATA   wsd;

SOCKET    sListen,sClient;

sockaddr_in    local,client;

int    iAddrSize;

HANDLE    hThread;

DWORD    dwThreadId;

info2thread infoParam;

//加载Winsock

if(WSAStartup(MAKEWORD(2,2),&wsd) != 0){

printf("Failed to load Winsock!\n");

exit(1);

}

//创建监听套接字及其地址信息结构体

sListen = socket(AF_INET,SOCK_STREAM,IPPROTO_IP);

local.sin_addr.s_addr = htonl(INADDR_ANY);

local.sin_port = htons(DEFAULT_PORT);

local.sin_family = AF_INET;

//j将套接字和地址信息绑定

if(bind(sListen,(const sockaddr*) &local,sizeof(local)) == SOCKET_ERROR){

printf("bind() failed:%d\n",WSAGetLastError());

return 1;

}

//监听

listen(sListen,7);

printf("Server is Ready, listening on Port:%d.\n>\n",ntohs(local.sin_port));

while(1){

//处理连接请求

iAddrSize = sizeof(client);

sClient = accept(sListen,(sockaddr*)&client,&iAddrSize);

if(sClient == INVALID_SOCKET){

printf("accept() failed:%d\n",WSAGetLastError());

return 1;

}

printf("Accepted Client: %s:%d\n",

inet_ntoa(client.sin_addr), ntohs(client.sin_port));

infoParam.info_addr_rev = client;     //infoParam用于构建传给线程的结构体,主要用于IP地址和Port端口的输出

infoParam.info_socket_rev = sClient;

//在vector中保存连接中的客户端Socket

vClientSockets.push_back(sClient);

//创建进程接收数据

hThread = CreateThread(NULL,0,ThreadProc,(LPVOID)&infoParam,0,&dwThreadId);

if (hThread == NULL){

printf("CreateThread() failed: %d\n", GetLastError());

break;

}

CloseHandle(hThread); //不再需要这个句柄，关掉它，但并非是关掉对应线程

}

//关闭

closesocket(sListen);

WSACleanup();

return 0;

}

DWORD WINAPI ThreadProc (PVOID pParam) {

int ret,errCode;

info2thread *pInfo = (info2thread*) pParam;

SOCKET sClient = pInfo->info_socket_rev,

sOther;

sockaddr_in client = pInfo->info_addr_rev;

char     szIPPort[BUF_SIZE],

szPort[7];

//构造客户端 "IP:Port" 标识

_itoa(ntohs(client.sin_port),szPort,10);  //itoa函数用于将整型数转化成对应的字符串，10表示十进制，末尾自动添'\0'

strcpy(szIPPort,inet_ntoa(client.sin_addr));  //拷贝IP

strcpy(szIPPort+strlen(inet_ntoa(client.sin_addr)),":");

strcpy(szIPPort+strlen(inet_ntoa(client.sin_addr))+1,szPort);  //拷贝Port

while(1){

//接收来自客户端的数据

ret = recv(sClient,szMessage,BUF_SIZE,0);

if (ret == SOCKET_ERROR){

errCode = WSAGetLastError();

switch(errCode){

case 10054: //10054：客户端主动退出时的错误代码

printf("%s:%d has exited.\n",inet_ntoa(client.sin_addr),ntohs(client.sin_port));

break;

default:

printf("recv() failed:%d from %s\n", errCode,szIPPort);

}

break;  //跳出while(1)循环

}

szMessage[ret] = '\0';

printf("Server%d REV %s: %s\n",     GetCurrentProcessId(),

szIPPort,

szMessage);

//向正在连接的所有其他客户端发送消息（聊天室）

for(vector<SOCKET>::iterator it = vClientSockets.begin();it != vClientSockets.end(); ++it){

if(*it == sClient)      continue;

sOther = *it;

//广播客户标识信息

ret = send(sOther,szIPPort,strlen(szIPPort),0);

if (ret == SOCKET_ERROR); //do nothing

//广播客户消息

ret = send(sOther,szMessage,strlen(szMessage),0);

if (ret == SOCKET_ERROR); //do nothing

}

}

//关闭套接字，从vector中删除对应的元素

for(vector<SOCKET>::iterator it = vClientSockets.begin(); it != vClientSockets.end();  ){

if(*it == sClient){

it = vClientSockets.erase(it);

break;

}

else{

++it;

}

}

closesocket(sClient);

return 0;

}

1. 客户端（Client.cpp）

#include <WinSock2.h>

#include <stdio.h>

#define DEFAULT_PORT        7321

#define BUF_SIZE 128

char szMessage[BUF_SIZE],

szRecieved[BUF_SIZE];

DWORD WINAPI ThreadProc (PVOID);

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

WSADATA wsd;

SOCKET sClient;

struct sockaddr_in server;

HANDLE    hThread;

DWORD    dwThreadId;

int ret;

// 加载Winsock

if(WSAStartup(MAKEWORD(2,2), &wsd) != 0){

printf("Failed to load Winsock library!\n");

return 1;

}

//创建套接字

sClient = socket(AF_INET,SOCK_STREAM,IPPROTO_IP);

if(sClient == INVALID_SOCKET){

printf("socket() failed on %d\n",WSAGetLastError());

return 1;

}

//填写服务器地址信息结构体

server.sin_addr.s_addr = inet_addr("127.0.0.1");

server.sin_port = htons(DEFAULT_PORT);

server.sin_family = AF_INET;

//查询服务器

//连接

if(connect(  sClient,(const sockaddr*)&server,

sizeof(server)) == SOCKET_ERROR){

printf("connect() failed: %d\n", WSAGetLastError());

return 1;

}

else

{

printf("This Client is Connected.\n>\n");

}

//创建一个用于不停接收服务器数据的进程

hThread = CreateThread(NULL,0,ThreadProc,(LPVOID)&sClient,0,&dwThreadId);

if (hThread == NULL){

printf("CreateThread() failed: %d, can't receive message from SERVER!\n", GetLastError());

}

CloseHandle(hThread); //不再需要这个句柄，关掉它，但并非是关掉对应线程

//发送数据

do{

gets_s(szMessage,BUF_SIZE-1);

ret = send(sClient,szMessage,strlen(szMessage),0);

if (ret == SOCKET_ERROR){

printf("send() failed: %d\n", WSAGetLastError());

break;

}

}while(ret);

//关闭套接字

closesocket(sClient);

WSACleanup();

return 0;

}

DWORD WINAPI ThreadProc (PVOID pParam){

SOCKET sRecv = *(SOCKET*)pParam;

int ret;

while(1){

//接收标识

ret = recv(sRecv,szRecieved,BUF_SIZE,0);

if(ret == SOCKET_ERROR){

printf("[Unknown]"); //标识接收失败，则统一认其为Unknown用户

}

else{

szRecieved[ret] = '\0';

printf("[%s]",szRecieved);

}

//分割符

printf(":");

//接收消息

ret = recv(sRecv,szRecieved,BUF_SIZE,0);

if(ret == SOCKET_ERROR){

printf("recv() from server failed: %d\n",WSAGetLastError());

continue;

}

szRecieved[ret] = '\0';

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

}

return 0;

}

运行结果截图：