HInternet works only one time - c++

Question

This code is in a C++ DLL injected in a game. (This is on a private server so it is legal). The code has to be executed multiple times. However, it works only the first time. It could be on the WCF end but I managed to send 2 and 5 successful requests from a .net dll loaded from the c++ dll before.
Since I didn't figure out why it was blocked after 2 and 5 requests, I decided to go all native but now I'm blocked after one request. I have a feeling it now has to do with the way I'm parsing the response.
The first execution gets a 200 code status and the second one gets a 0.
edit : my fire wall is turned off.
HINTERNET hInternet = InternetOpen(_T("MyApp"), INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
HINTERNET hConnect = InternetConnect(hInternet, _T("localhost"), INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);
LPCSTR rgpszAcceptTypes[] = { _T("application/json"), NULL };
HINTERNET hRequest = HttpOpenRequest(hConnect, _T("POST"), _T("/xxxBackend/service1.svc/SaveDataVoid"), NULL, NULL, rgpszAcceptTypes, 0, 0);
HttpAddRequestHeaders(hRequest, _T("Content-Type: application/json\r\n"), -1, HTTP_ADDREQ_FLAG_ADD);
char *JsonData = "{\"data\":{\"AccountName\":\"\",\"CharName\":\"SilverDeth-IV\",\"GameDiff\":\"1\",\"CompressedData\":[8228138568842941382,8247906688399250381,8244242016143283142]}}";
HttpSendRequest(hRequest, NULL, 0, JsonData, strlen(JsonData));
DWORD StatusCode = 0;
DWORD StatusCodeLen = sizeof(StatusCode);
HttpQueryInfo(hRequest, HTTP_QUERY_STATUS_CODE | HTTP_QUERY_FLAG_NUMBER, &StatusCode, &StatusCodeLen, NULL);
if (StatusCode == 200)
{
char *lpBuffer[2000];
DWORD lpdwNumberOfBytesRead = 0;
InternetQueryDataAvailable(hRequest, &StatusCodeLen, 0, 0);
bool bRetval = InternetReadFile(hRequest, lpBuffer, 2000, &lpdwNumberOfBytesRead);
}
InternetCloseHandle(hRequest);
InternetCloseHandle(hConnect);
InternetCloseHandle(hInternet);

Answer 1

The code you have shown is not doing ANY error handling at all. Add that in, and then see where the failure is really occurring. The fact that StatusCode is 0 means HttpQueryInfo() is failing, which could happen if you did not obtain a valid hRequest to begin with.
BTW, rgpszAcceptTypes needs to be declared as LPCTSTR instead of LPCSTR, and you should be using the TEXT() macro instead of the _T() macro. TEXT() belongs to the Win32 API, but _T() belongs to the C runtime library, which you are not using in this code.
Try this:
void InetError(LPCTSTR msg)
{
DWORD dwErr = GetLastError();
if (dwErr == ERROR_INTERNET_EXTENDED_ERROR)
{
DWORD dwInetErr = 0;
LPTSTR szResp = NULL;
DWORD dwLength = 0;
InternetGetLastResponseInfo(&dwInetErr, NULL, &dwLength);
if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
{
szResp = new TCHAR[dwLength+1];
InternetGetLastResponseInfo(&dwInetErr, szResp, &dwLength);
}
// use msg, szResp, and dwInetErr as needed...
delete[] szResp;
}
else
{
// use msg and dwErr as needed...
}
}
...
HINTERNET hInternet = NULL;
HINTERNET hConnect = NULL;
HINTERNET hRequest = NULL;
hInternet = InternetOpen(TEXT("MyApp"), INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
if (!hInternet)
{
InetError(TEXT("InternetOpen failed"));
goto done;
}
hConnect = InternetConnect(hInternet, TEXT("localhost"), INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);
if (!hConnect)
{
InetError(TEXT("InternetConnect failed"));
goto done;
}
LPCTSTR rgpszAcceptTypes[] = { TEXT("application/json"), NULL };
hRequest = HttpOpenRequest(hConnect, TEXT("POST"), TEXT("/xxxBackend/service1.svc/SaveDataVoid"), NULL, NULL, rgpszAcceptTypes, 0, 0);
if (!hRequest)
{
InetError(TEXT("HttpOpenRequest failed"));
goto done;
}
if (!HttpAddRequestHeaders(hRequest, TEXT("Content-Type: application/json\r\n"), -1, HTTP_ADDREQ_FLAG_ADD))
{
InetError(TEXT("HttpAddRequestHeaders failed"));
goto done;
}
char *JsonData = "{\"data\":{\"AccountName\":\"\",\"CharName\":\"SilverDeth-IV\",\"GameDiff\":\"1\",\"CompressedData\":[8228138568842941382,8247906688399250381,8244242016143283142]}}";
if (!HttpSendRequest(hRequest, NULL, 0, JsonData, strlen(JsonData)))
{
InetError(TEXT("HttpSendRequest failed"));
goto done;
}
DWORD StatusCode = 0;
DWORD StatusCodeLen = sizeof(StatusCode);
if (!HttpQueryInfo(hRequest, HTTP_QUERY_STATUS_CODE | HTTP_QUERY_FLAG_NUMBER, &StatusCode, &StatusCodeLen, NULL))
{
InetError(TEXT("HttpQueryInfo failed"));
goto done;
}
if (StatusCode == 200)
{
BYTE Buffer[2000];
DWORD dwNumberOfBytes = 0;
DWORD dwNumberOfBytesRead = 0;
if (!InternetQueryDataAvailable(hRequest, &dwNumberOfBytes, 0, 0))
{
InetError(TEXT("InternetQueryDataAvailable failed"));
goto done;
}
if (!InternetReadFile(hRequest, Buffer, min(dwNumberOfBytes, sizeof(Buffer)), &dwNumberOfBytesRead))
{
InetError(TEXT("InternetReadFile failed"));
goto done;
}
//...
}
done:
if (hRequest) InternetCloseHandle(hRequest);
if (hConnect) InternetCloseHandle(hConnect);
if (hInternet) InternetCloseHandle(hInternet);