Is there any good example of http upload using WinInet c++ library

Question

I cannot get my code to work :/

Answer 1

Here's a quick example from Microsoft.

   static TCHAR hdrs[] =
      _T("Content-Type: application/x-www-form-urlencoded");
   static TCHAR frmdata[] =
      _T("name=John+Doe&userid=hithere&other=P%26Q");
  static LPSTR accept[2]={"*/*", NULL};

   // for clarity, error-checking has been removed
   HINTERNET hSession = InternetOpen("MyAgent",
      INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
   HINTERNET hConnect = InternetConnect(hSession, _T("ServerNameHere"),
      INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 1);
   HINTERNET hRequest = HttpOpenRequest(hConnect, "POST",
      _T("FormActionHere"), NULL, NULL, accept, 0, 1);
   HttpSendRequest(hRequest, hdrs, strlen(hdrs), frmdata, strlen(frmdata));
   // close any valid internet-handles

The example comes from here.

Answer 2

Eventually I found some working example on the web

static char szRawData[5000];
  memset(szRawData, 0x11, sizeof(szRawData));

  //
  // CIHandle is just a wrapper class for HINTERNET, that closes handle in destructor
  //
  CIHandle hIntrn = InternetOpen( "LiveUpdate"), 
                                  INTERNET_OPEN_TYPE_PRECONFIG_WITH_NO_AUTOPROXY,
                                  NULL,
                                  NULL,
                                  0);
  if (!hIntrn)
    return printf("No Internet connection: %li.\n", GetLastError());

  CIHandle hConn = InternetConnect( hIntrn, 
                                    "65.254.250.104",
                                    INTERNET_DEFAULT_HTTP_PORT,
                                    NULL,
                                    NULL,
                                    INTERNET_SERVICE_HTTP,
                                    0,
                                    NULL);
  if (!hConn)
    return printf("Connection to update server failed: %li.\n", GetLastError());

  DWORD dwOpenRequestFlags = INTERNET_FLAG_IGNORE_REDIRECT_TO_HTTP |
                             INTERNET_FLAG_IGNORE_REDIRECT_TO_HTTPS |
                             INTERNET_FLAG_KEEP_CONNECTION |
                             INTERNET_FLAG_NO_AUTO_REDIRECT |
                             INTERNET_FLAG_NO_COOKIES |
                             INTERNET_FLAG_NO_CACHE_WRITE |
                             INTERNET_FLAG_NO_UI |
                             INTERNET_FLAG_RELOAD;

  CIHandle hReq = HttpOpenRequest(hConn,
                                  "POST",
                                  "upload.php",
                                  "HTTP/1.0",
                                  NULL,
                                  NULL,
                                  dwOpenRequestFlags,
                                  NULL);

  ZString strBoundary = "---------------------------autoupdater";
  ZString strContentHeader =  "Host: www.mydomain_at_powweb.com\r\n"
                              "Content-Type: multipart/form-data; boundary=";
  strContentHeader+=strBoundary;

  HttpAddRequestHeaders(hReq, strContentHeader, strContentHeader.length(), HTTP_ADDREQ_FLAG_ADD);


  ZString strHeaders;
  strHeaders.precache(16384);
  sprintf(strHeaders,
          "--%s\r\n"
          "Content-Disposition: form-data; name=\"userfile\"; "
          "filename=\"test.raw\"\r\n"
          "Content-Type: application/octet-stream\r\n\r\n",
          (LPCTSTR)strBoundary);

  tCharSeq s;//this is a just a dynamic array of bytes;
  //
  // append headers and file to request:
  //
  s.precache(16384);
  s.append(strHeaders.length(), strHeaders);
  //append with file data:
  s.append(2000, szRawData); //<------------------- depending on this size, SendRequest fails.
  //trailing end of data:
  s.append(4,"\r\n--");
  s.append(strBoundary.length(), (LPTSTR)strBoundary);
  s.append(4,"--\r\n");

  InternetSetOption(hReq, INTERNET_OPTION_USERNAME, "username\0", 9);
  InternetSetOption(hReq, INTERNET_OPTION_PASSWORD, "password\0", 9);

  if (!HttpSendRequest(hReq, NULL, 0, (void*)s.getBuffer(), s.length()))
    return printf("HttpSendRequest failed: %li.\n", GetLastError());