http 代理

C/C++ code

#include <stdio.h>
#include <iostream>
#include <winsock2.h>
#include <process.h>
#include "SockInit.h"
using namespace std;
#define MAX_REQUESTLINE_LEN  2048  // IE请求行长度
void __cdecl ServerThreadProc(void *param);
int TCPsend(SOCKET s,const char*buf,int len,int flags);
int TCPrecv(SOCKET s,const char*buf,int len,int flags);
/************************************************
调试环境:Visual C++6.0 SP6+platform SDK 2003 R2
程序名称:HTTP proxy Server(HttpProxySvr.cpp)
功能    :IE通过设置代理方式上网,IE所有请求均
先发到该代理服务器,代理服务器
将请求直接转发给webserver,
后从webserver读取响应后发回IE
存在的问题: IE设置代理后只能显示网页文本内容,图片
显示不了,若网页嵌有歌曲,歌曲也下载不
下来(自然歌曲也播放不了)...
Date:    2007/10/12
author:  liqisong
eamil :  liqisong611@yahoo.com.cn
**************************************************/
int main()
{
USHORT uPort=9999;   // 通信端口

WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD( 2, 2 );
err = WSAStartup( wVersionRequested, &wsaData );
if ( err != 0 )
{
return 0;
}
if ( LOBYTE( wsaData.wVersion ) != 2 ||
HIBYTE( wsaData.wVersion ) != 2 )
{
WSACleanup( );
return  0;
}
SOCKET sListen = socket(AF_INET,SOCK_STREAM,0);
if(sListen == INVALID_SOCKET)
{
printf("Failed socket(),error code :%d",WSAGetLastError());
return 0;
}
sockaddr_in sin;
sin.sin_addr.S_un.S_addr = INADDR_ANY;
sin.sin_family =AF_INET;
sin.sin_port = htons(uPort);
if(bind(sListen,(sockaddr*)&sin,sizeof(sin))==SOCKET_ERROR)
{
printf("Failed bind(),error code :%d",WSAGetLastError());
closesocket(sListen);
return 0;
}
int res =listen(sListen,200);
sockaddr_in addrRemote;
int len =sizeof(addrRemote);
while(true)
{
SOCKET sNew = accept(sListen,(sockaddr*)&addrRemote,&len);
if(sNew == INVALID_SOCKET)
{
printf("Failed accept(),error code :%d",WSAGetLastError());
return 0;
}
printf("收到一个IE连接(IP:%s)\n",inet_ntoa(addrRemote.sin_addr));
// 创建一个线程处理该连接 (每客户单线程模式...)
        _beginthread(ServerThreadProc,0,(void*)sNew);
}
closesocket(sListen);
return 0;
}
void __cdecl ServerThreadProc(void *param)
{
SOCKET sock = (SOCKET)param;   //与浏览器连接的套接口

char request[MAX_REQUESTLINE_LEN];
memset(request,0,MAX_REQUESTLINE_LEN);
int res =recv(sock,request,MAX_REQUESTLINE_LEN,0);  // 接收浏览器(客户端)发来的请求
    if(res==0)
{
printf("连接断开\n");
closesocket(sock);
return;
}
shutdown(sock,SD_RECEIVE);
//  打印收到的请求
    printf("header length :%d  header: %s\n",res,request);
// 分析请求行(分离出WebServer域名)
    char szAddrName[1024]={0}; //域名
    int i =11;
while(request[i]!='/'&&i<res)
{
szAddrName[i-11] = request[i];
i++;
}
szAddrName[i-11]='\0';
printf("WebServer address: %s\n\n",szAddrName);
// 向WebServer提交请求
    SOCKADDR_IN   saServer;
LPHOSTENT     lphostent;
SOCKET        hsocket;
int   nRet;
lphostent=gethostbyname(szAddrName); // 通过域名获得目标WebServer的IP 
    if(lphostent==NULL)
{
printf("Failed gethostbyname(),error code:%d\n",WSAGetLastError());
return ;
}
hsocket = socket(AF_INET,SOCK_STREAM,0);
if(hsocket==INVALID_SOCKET)
{
printf("Failed socket(),error code:%d\n",WSAGetLastError());
return ;
}
saServer.sin_family = AF_INET;
saServer.sin_port = htons(80);
saServer.sin_addr= *((LPIN_ADDR)*lphostent->h_addr_list);
nRet = connect(hsocket,(LPSOCKADDR)&saServer,sizeof(SOCKADDR_IN));
if(nRet==SOCKET_ERROR)
{
printf("Failed connect(),error code:%d\n",WSAGetLastError());
closesocket(hsocket);
return;
}
//  向webserver转发IE请求 
    nRet = TCPsend(hsocket,request,strlen(request),0);
char   dest[1000];
nRet=1;
int senlen=0;
while(nRet>0)
{
memset(dest,0,1000);
nRet=recv(hsocket,dest,sizeof(dest)-1,0);  // 从webserver获取数据 
        if(nRet==0)
{
printf("与webserver(%s)的连接关闭\n",szAddrName);
break;
}
else  if(nRet==SOCKET_ERROR )
{
printf("Failed recv(),error code:%d\n",WSAGetLastError());
break;
}
dest[nRet]='\0';
senlen = TCPsend(sock,dest,strlen(dest),0);  //将数据转发给IE浏览器
        if(senlen==0)
{
sockaddr_in sin;
int len = sizeof(sin);
if(getpeername(sock,(sockaddr*)&sin,&len)== SOCKET_ERROR)
{
printf("Failed getpeername(),error code:%d\n",WSAGetLastError());
break;
}
printf("与浏览器(%s)的一个连接关闭...\n",inet_ntoa(sin.sin_addr));
break;
}
else if(senlen==SOCKET_ERROR)
{
printf("Failed send(),error code:%d\n",WSAGetLastError());
break;
}
// printf("%s\n",dest);

} // end of while(nRet>0)   

closesocket(sock);
closesocket(hsocket);
}
int TCPsend(SOCKET s,const char*buf,int len,int flags)
{
int n=0,sendCount=0;
int length =len;
if(buf==NULL)
return 0;
while(length>0)
{
n=send(s,buf+sendCount,length,flags); //发送数据，
        if(n==SOCKET_ERROR)//网络出现异常
        {
printf("Failed send(),error code:%d\n",WSAGetLastError());
break;
}
length-=n;
sendCount+=n;
}
return sendCount; // 返回已发送的字节数
}
int TCPrecv(SOCKET s,char *buf,int len,int flags)
{
int nRev=0,recvCount=0;
int length =len;
if(buf==NULL)
return 0;
// 循环接收数据
    while(length>0)
{
nRev =recv(s,buf+recvCount,length,flags);
if(nRev==SOCKET_ERROR)//网络出现异常
        {
printf("Failed recv(),error code:%d\n",WSAGetLastError());
break;
}
length-=nRev;
recvCount+=nRev;
}
return recvCount; //返回接收到的字节数
}

以下一行出错了
senlen = TCPsend(sock,dest,strlen(dest),0);  //将数据转发给IE浏览器

因为接受图片不是字符串，用strlen()不会正确,用nRet即可。