Purpose of WINHTTP_QUERY_URI in WinHTTP?

Question

What HTTP header exactly can be queried using WINHTTP_QUERY_URI flag with WinHttpQueryHeaders function? After reading its description I was under impression this flag was supposed to be used to get the URI of the request specified in WinHttpOpenRequest function. Yet the following program gives me an error code 12019 ERROR_INTERNET_INCORRECT_HANDLE_STATE (and 12150 ERROR_HTTP_HEADER_NOT_FOUND if I uncomment two commented lines).

#include <cstdio>
#include <windows.h>
#include <winhttp.h>
#pragma comment(lib, "winhttp.lib")
int main()
{
    HINTERNET hSession = WinHttpOpen(nullptr, WINHTTP_ACCESS_TYPE_NO_PROXY, WINHTTP_NO_PROXY_NAME, WINHTTP_NO_PROXY_BYPASS, 0);
    HINTERNET hConnect = WinHttpConnect(hSession, L"www.ietf.org", INTERNET_DEFAULT_HTTP_PORT, 0);
    HINTERNET hRequest = WinHttpOpenRequest(hConnect, L"GET", L"/rfc/rfc2616.txt", nullptr, WINHTTP_NO_REFERER, nullptr, 0);

    //WinHttpSendRequest(hRequest, WINHTTP_NO_ADDITIONAL_HEADERS, 0, WINHTTP_NO_REQUEST_DATA, 0, 0, 0);
    //WinHttpReceiveResponse(hRequest, 0);

    wchar_t url[1024] = {};
    DWORD url_size = sizeof(url);
    auto success = WinHttpQueryHeaders(hRequest, WINHTTP_QUERY_URI, WINHTTP_HEADER_NAME_BY_INDEX, url, &url_size, WINHTTP_NO_HEADER_INDEX);
    auto error_code = GetLastError();
    wprintf(L"success=%d error_code=%u url=%s", success, error_code, url);

    WinHttpCloseHandle(hRequest);
    WinHttpCloseHandle(hConnect);
    WinHttpCloseHandle(hSession);
}

P.S. Yes, I know I can get request URI using WinHttpQueryOption and WINHTTP_OPTION_URL, no need to point that out.

EDIT. Adding WINHTTP_QUERY_FLAG_REQUEST_HEADERS flag as per Captain Obvlious answer below (which totally makes sense if WINHTTP_QUERY_URI was indeed supposed to return request URI) did not make much difference: now with or without WinHttpSendRequest and WinHttpReceiveResponse calls WinHttpQueryHeaders function produces error code 12150 ERROR_HTTP_HEADER_NOT_FOUND.

How did you solve the problemm... I am having the exact same problem.. I am trying to download a file through ssl and exactly confronting the same issues on the answer and the OP. what to do? can you please help me. — Ahmed Can Unbay, Jan 14 '20 at 18:07
https://stackoverflow.com/questions/59730223/receiving-12030-at-winhttpreceiveresponse — Ahmed Can Unbay, Jan 14 '20 at 18:09
no i think i dont receive 12030 as much but im receving the same errors as you — Ahmed Can Unbay, Jan 14 '20 at 18:09

score 1 · Answer 1 · answered Apr 16 '13 at 19:53

1

You are querying the response headers of the request which do not contain the URI. You need to include the WINHTTP_QUERY_FLAG_REQUEST_HEADERS modifier flag to retrieve from the request header.

WinHttpQueryHeaders(
    hRequest,
    WINHTTP_QUERY_URI | WINHTTP_QUERY_FLAG_REQUEST_HEADERS,
    WINHTTP_HEADER_NAME_BY_INDEX,
    url,
    &url_size,
    WINHTTP_NO_HEADER_INDEX);

answered Apr 16 '13 at 19:53

Captain Obvlious

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Good catch, yet adding this flag does not solve the problem - now instead of error code 12019 I am getting error code 12150. Still, I'll update my post to include `WINHTTP_QUERY_FLAG_REQUEST_HEADERS` flag (which I totally forgot about). – PowerGamer Apr 16 '13 at 20:00
AFAIK `WinHttpSendRequest` and `WinHttpReceiveResponse` still have to be called. – Captain Obvlious Apr 16 '13 at 20:03
How to fix this ?? – Ahmed Can Unbay Jan 14 '20 at 18:09

Purpose of WINHTTP_QUERY_URI in WinHTTP?

1 Answers1