ENH : Remove the use of the CurlResource class in RetrieveFileMulti method

      Using the CurlResource in the loop will make the easy handle destroyed
      at the end of each loop, then making the multi handle not working

Code/UtilitiesAdapters/CurlAdapters/otbCurlHelper.cxx

@@ -312,10 +312,14 @@ int CurlHelper::RetrieveFileMulti(const std::vector<std::string>& listURLs,
   filename = listFilename.begin();
   while (filename != listFilename.end())
     {
-    FileResource lOutputFile((*filename).c_str());
-    
+    FILE* lOutputFile = fopen((*filename).c_str(), "wb");
+    if (lOutputFile == NULL)
+      {
+      itkExceptionMacro(<< "otbCurlHelper: bad file name: " << (*filename).c_str());
+      }
+
     // Add file to vector
-    listFiles.push_back(lOutputFile.GetFileResource());
+    listFiles.push_back(lOutputFile);
     ++filename;
     }
 
@@ -328,19 +332,29 @@ int CurlHelper::RetrieveFileMulti(const std::vector<std::string>& listURLs,
   while ((url != listURLs.end()) && (file != listFiles.end()))
     {
     otbMsgDevMacro(<< "Retrieving: " << (*url).data());
-    CurlResource lEasyHandleResource;
-    
+    CURL * lEasyHandle;
+    lEasyHandle = curl_easy_init();
+
+    if (!lEasyHandle)
+      {
+      itkExceptionMacro(<< "otbCurlHelper: Curl easy handle init error.");
+      }
+
     // Param easy handle
-    otbCurlCall(curl_easy_setopt(lEasyHandleResource.GetCurlResource(), CURLOPT_USERAGENT, m_Browser.data()));
-    otbCurlCall(curl_easy_setopt(lEasyHandleResource.GetCurlResource(), CURLOPT_URL, (*url).data()));
-    otbCurlCall(curl_easy_setopt(lEasyHandleResource.GetCurlResource(), CURLOPT_WRITEFUNCTION, &Self::CallbackWriteDataToFile));
-    otbCurlCall(curl_easy_setopt(lEasyHandleResource.GetCurlResource(), CURLOPT_WRITEDATA, (void*) (*file)));
+    // the otbCurlCall is not used here cause we are not using the
+    // CurlResource class : Using the CurlResource class in the loop
+    // will make the object CurlResource destroyed at the end of each
+    // loop, making the multi handle not working.    
+    curl_easy_setopt(lEasyHandle, CURLOPT_USERAGENT, m_Browser.data());
+    curl_easy_setopt(lEasyHandle, CURLOPT_URL, (*url).data());
+    curl_easy_setopt(lEasyHandle, CURLOPT_WRITEFUNCTION, &Self::CallbackWriteDataToFile);
+    curl_easy_setopt(lEasyHandle, CURLOPT_WRITEDATA, (void*) (*file));
 
     // Add easy handle to multi handle
-    curl_multi_add_handle(multiHandle.GetCurlMultiResource(), lEasyHandleResource.GetCurlResource());
+    curl_multi_add_handle(multiHandle.GetCurlMultiResource(), lEasyHandle);
 
     // Add hanle to vector
-    listCurlHandles.push_back(lEasyHandleResource.GetCurlResource());
+    listCurlHandles.push_back(lEasyHandle);
     ++url;
     ++file;
     }
@@ -411,7 +425,18 @@ int CurlHelper::RetrieveFileMulti(const std::vector<std::string>& listURLs,
     }
 
   // Cleanup
+  // Close files
+  for (unsigned int currentFile = 0; currentFile < listFiles.size(); currentFile++)
+    {
+    fclose(listFiles[currentFile]);
+    }
   listFiles.clear();
+
+  // Cleanup easy handles
+  for (unsigned int currentHandle = 0; currentHandle < listCurlHandles.size(); currentHandle++)
+    {
+    curl_easy_cleanup(listCurlHandles[currentHandle]);
+    }
   listCurlHandles.clear();
   
 #else