Setting the Internet Explorer Proxy in cURL Librar

问题:

Well I would like to use the default Internet Explorer connection proxy settings to make a request in cURL in C++, this is my example code:

CURL *curl;
CURLcode result;

curl = curl_easy_init();

char errorBuffer[CURL_ERROR_SIZE];

if (curl)
{
// Now set up all of the curl options
curl_easy_setopt(curl, CURLOPT_ERRORBUFFER, errorBuffer);
curl_easy_setopt(curl, CURLOPT_URL, url);
curl_easy_setopt(curl, CURLOPT_HEADER, 0);
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
curl_easy_setopt(curl, CURLOPT_COOKIEJAR, "cookies.txt");

// Attempt to retrieve the remote page
result = curl_easy_perform(curl);

// Always cleanup
curl_easy_cleanup(curl);
}

How do I do to retrieve the Proxy Internet Explorer settings and then pass to my cURL so it can be able to make requests using the proxy ?

Thanks in advance.

回答1:

The WinHttpGetIEProxyConfigForCurrentUser function retrieves the Internet Explorer proxy configuration for the current user.

    #include "stdafx.h" 
#include <Windows.h>
#include <Winhttp.h>
#include <iostream>

using namespace std;
void main() 
{ 
    WINHTTP_CURRENT_USER_IE_PROXY_CONFIG MyProxyConfig;

    if(!WinHttpGetIEProxyConfigForCurrentUser(&MyProxyConfig))
    { 
        //check the error DWORD Err = GetLastError(); 
        DWORD Err = GetLastError(); 
        cout << "WinHttpGetIEProxyConfigForCurrentUser failed with the following error number: " << Err << endl;
        switch (Err) 
       {
            case ERROR_FILE_NOT_FOUND: 
            cout << "The error is ERROR_FILE_NOT_FOUND" << endl; 
            break; 
            case ERROR_WINHTTP_INTERNAL_ERROR:
            cout << "ERROR_WINHTTP_INTERNAL_ERROR" << endl; 
            break; 
            case ERROR_NOT_ENOUGH_MEMORY:
            cout << "ERROR_NOT_ENOUGH_MEMORY" << endl; 
            break; 
            default: cout << "Look up error in header file." << endl; 
        }//end switch 
    }//end if 
    else 
    { 
        //no error so check the proxy settings and free any strings 
        cout << "Auto Detect is: " << MyProxyConfig.fAutoDetect << endl; 

        if(NULL != MyProxyConfig.lpszAutoConfigUrl) 
        { 
            wcout << "AutoConfigURL (MyProxyConfig.lpszAutoConfigUrl) is: " << MyProxyConfig.lpszAutoConfigUrl << endl; 
            GlobalFree(MyProxyConfig.lpszAutoConfigUrl);
        } 
        if(NULL != MyProxyConfig.lpszProxy) 
        { 
            wcout << "AutoConfigURL (MyProxyConfig.lpszProxy) is: " << MyProxyConfig.lpszProxy << endl;
            GlobalFree(MyProxyConfig.lpszProxy);
         }
        if(NULL != MyProxyConfig.lpszProxyBypass) 
        {
             wcout << "AutoConfigURL (is: " << MyProxyConfig.lpszProxyBypass << endl;                      
             GlobalFree(MyProxyConfig.lpszProxyBypass); 
        }
    }//end else 
    cout << "finished!"; 
    system("PAUSE");
}//end main

回答2:

You want to use InternetQueryOption with INTERNET_OPTION_PROXY (documentation) to find the current proxy setting and then it's just a question of passing the proxy setting to curl as normal.

回答3:

first,use windows api to get the proxy server, then use the curl_easy_setopt to set the proxy to the curl.

Get the proxy: WinHttpGetIEProxyConfigForCurrentUserthis api can get the proxy,but no WPAD. And if someone use "Use automatic proxy configuration",should use the WinHttpGetProxyForUrl api to get the proxy.All in msdn:http://msdn.microsoft.com/en-us/library/windows/desktop/aa384096(v=vs.85).aspx

Set the proxy:curl_easy_setopt(hCurl, CURLOPT_PROXY, astrProxy.c_str());