Bug 1013211 - Use the final resource URI after redirects etc as the source URI when dragging an image. r=roc

dom/base/nsContentAreaDragDrop.cpp

@@ -515,14 +515,6 @@ DragDataProducer::Produce(DataTransfer* aDataTransfer,
         // grab the href as the url, use alt text as the title of the
         // area if it's there.  the drag data is the image tag and src
         // attribute.
-        nsCOMPtr<nsIURI> imageURI;
-        image->GetCurrentURI(getter_AddRefs(imageURI));
-        if (imageURI) {
-          nsAutoCString spec;
-          imageURI->GetSpec(spec);
-          CopyUTF8toUTF16(spec, mUrlString);
-        }
-
         nsCOMPtr<nsIDOMElement> imageElement(do_QueryInterface(image));
         // XXXbz Shouldn't we use the "title" attr for title?  Using
         // "alt" seems very wrong....
@@ -530,13 +522,10 @@ DragDataProducer::Produce(DataTransfer* aDataTransfer,
           imageElement->GetAttribute(NS_LITERAL_STRING("alt"), mTitleString);
         }
 
-        if (mTitleString.IsEmpty()) {
-          mTitleString = mUrlString;
-        }
-
-        nsCOMPtr<imgIRequest> imgRequest;
+        mUrlString.Truncate();
 
         // grab the image data, and its request.
+        nsCOMPtr<imgIRequest> imgRequest;
         nsCOMPtr<imgIContainer> img =
           nsContentUtils::GetImageFromContent(image,
                                               getter_AddRefs(imgRequest));
@@ -547,7 +536,7 @@ DragDataProducer::Produce(DataTransfer* aDataTransfer,
         // Fix the file extension in the URL if necessary
         if (imgRequest && mimeService) {
           nsCOMPtr<nsIURI> imgUri;
-          imgRequest->GetURI(getter_AddRefs(imgUri));
+          imgRequest->GetCurrentURI(getter_AddRefs(imgUri));
 
           nsCOMPtr<nsIURL> imgUrl(do_QueryInterface(imgUri));
 
@@ -568,6 +557,7 @@ DragDataProducer::Produce(DataTransfer* aDataTransfer,
 
               // pass out the image source string
               CopyUTF8toUTF16(spec, mImageSourceString);
+              mUrlString = mImageSourceString;
 
               bool validExtension;
               if (extension.IsEmpty() || 
@@ -602,6 +592,18 @@ DragDataProducer::Produce(DataTransfer* aDataTransfer,
             }
           }
         }
+        if (mUrlString.IsEmpty()) {
+          nsCOMPtr<nsIURI> imageURI;
+          image->GetCurrentURI(getter_AddRefs(imageURI));
+          if (imageURI) {
+            nsAutoCString spec;
+            imageURI->GetSpec(spec);
+            CopyUTF8toUTF16(spec, mUrlString);
+          }
+        }
+        if (mTitleString.IsEmpty()) {
+          mTitleString = mUrlString;
+        }
 
         if (parentLink) {
           // If we are dragging around an image in an anchor, then we

image/public/imgIRequest.idl

@@ -19,7 +19,7 @@ interface nsIPrincipal;
  * @version 0.1
  * @see imagelib2
  */
-[scriptable, builtinclass, uuid(710f22f0-558b-11e4-8ed6-0800200c9a66)]
+[scriptable, builtinclass, uuid(dc61f0ea-4139-4c2a-ae69-cec82d33e089)]
 interface imgIRequest : nsIRequest
 {
   /**
@@ -83,6 +83,11 @@ interface imgIRequest : nsIRequest
    */
   readonly attribute nsIURI URI;
 
+  /**
+   * The URI of the resource we ended up loading after all redirects, etc.
+   */
+  readonly attribute nsIURI currentURI;
+
   readonly attribute imgINotificationObserver notificationObserver;
 
   readonly attribute string mimeType;

image/src/imgRequest.cpp

@@ -40,14 +40,17 @@ using namespace mozilla;
 using namespace mozilla::image;
 
 #if defined(PR_LOGGING)
-PRLogModuleInfo *
+PRLogModuleInfo*
 GetImgLog()
 {
-  static PRLogModuleInfo *sImgLog;
+  static PRLogModuleInfo* sImgLog;
   if (!sImgLog)
     sImgLog = PR_NewLogModule("imgRequest");
   return sImgLog;
 }
+#define LOG_TEST(level) (GetImgLog() && PR_LOG_TEST(GetImgLog(), (level)))
+#else
+#define LOG_TEST(level) false
 #endif
 
 NS_IMPL_ISUPPORTS(imgRequest,
@@ -367,6 +370,21 @@ nsresult imgRequest::GetURI(ImageURL **aURI)
   return NS_ERROR_FAILURE;
 }
 
+nsresult imgRequest::GetCurrentURI(nsIURI **aURI)
+{
+  MOZ_ASSERT(aURI);
+
+  LOG_FUNC(GetImgLog(), "imgRequest::GetCurrentURI");
+
+  if (mCurrentURI) {
+    *aURI = mCurrentURI;
+    NS_ADDREF(*aURI);
+    return NS_OK;
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
 nsresult imgRequest::GetImageErrorCode()
 {
   return mImageErrorCode;
@@ -1064,16 +1082,24 @@ imgRequest::OnRedirectVerifyCallback(nsresult result)
   mTimedChannel = do_QueryInterface(mChannel);
   mNewRedirectChannel = nullptr;
 
-#if defined(PR_LOGGING)
-  nsAutoCString oldspec;
-  if (mCurrentURI)
-    mCurrentURI->GetSpec(oldspec);
-  LOG_MSG_WITH_PARAM(GetImgLog(), "imgRequest::OnChannelRedirect", "old", oldspec.get());
-#endif
+  if (LOG_TEST(PR_LOG_DEBUG)) {
+    nsAutoCString spec;
+    if (mCurrentURI)
+      mCurrentURI->GetSpec(spec);
+    LOG_MSG_WITH_PARAM(GetImgLog(), "imgRequest::OnChannelRedirect", "old", spec.get());
+  }
 
   // make sure we have a protocol that returns data rather than opens
   // an external application, e.g. mailto:
   mChannel->GetURI(getter_AddRefs(mCurrentURI));
+
+  if (LOG_TEST(PR_LOG_DEBUG)) {
+    nsAutoCString spec;
+    if (mCurrentURI)
+      mCurrentURI->GetSpec(spec);
+    LOG_MSG_WITH_PARAM(GetImgLog(), "imgRequest::OnChannelRedirect", "new", spec.get());
+  }
+
   bool doesNotReturnData = false;
   nsresult rv =
     NS_URIChainHasFlags(mCurrentURI, nsIProtocolHandler::URI_DOES_NOT_RETURN_DATA,

image/src/imgRequest.h

@@ -137,6 +137,7 @@ public:
 
   // OK to use on any thread.
   nsresult GetURI(ImageURL **aURI);
+  nsresult GetCurrentURI(nsIURI **aURI);
 
   nsresult GetImageErrorCode(void);
 

image/src/imgRequestProxy.cpp

@@ -537,6 +537,14 @@ NS_IMETHODIMP imgRequestProxy::GetURI(nsIURI **aURI)
   return NS_OK;
 }
 
+nsresult imgRequestProxy::GetCurrentURI(nsIURI **aURI)
+{
+  if (!GetOwner())
+    return NS_ERROR_FAILURE;
+
+  return GetOwner()->GetCurrentURI(aURI);
+}
+
 nsresult imgRequestProxy::GetURI(ImageURL **aURI)
 {
   if (!mURI)