# HG changeset patch
# User Rafał Mużyło <galtgendo@o2.pl>
# Parent 69e253891ca3839b6d4b8f5cb7c0e6950bb66902
Fix animated gif flickering bug 597174

diff --git a/modules/libpr0n/decoders/gif/nsGIFDecoder2.cpp b/modules/libpr0n/decoders/gif/nsGIFDecoder2.cpp
--- a/modules/libpr0n/decoders/gif/nsGIFDecoder2.cpp
+++ b/modules/libpr0n/decoders/gif/nsGIFDecoder2.cpp
@@ -197,30 +197,29 @@ static NS_METHOD ReadDataOut(nsIInputStr
 }
 
 // Push any new rows according to mCurrentPass/mLastFlushedPass and
 // mCurrentRow/mLastFlushedRow.  Note: caller is responsible for
 // updating mlastFlushed{Row,Pass}.
 nsresult
 nsGIFDecoder2::FlushImageData(PRUint32 fromRow, PRUint32 rows)
 {
-  nsIntRect r(0, fromRow, mGIFStruct.width, rows);
+  nsIntRect r(mGIFStruct.x_offset, mGIFStruct.y_offset + fromRow, mGIFStruct.width, rows);
 
   // Update image  
   nsresult rv = mImageContainer->FrameUpdated(mGIFStruct.images_decoded, r);
   if (NS_FAILED(rv)) {
     return rv;
   }
 
   // Offset to the frame position
   // Only notify observer(s) for first frame
   if (!mGIFStruct.images_decoded && mObserver) {
     PRUint32 imgCurFrame;
     mImageContainer->GetCurrentFrameIndex(&imgCurFrame);
-    r.y += mGIFStruct.y_offset;
     mObserver->OnDataAvailable(nsnull, imgCurFrame == PRUint32(mGIFStruct.images_decoded), &r);
   }
   return NS_OK;
 }
 
 nsresult
 nsGIFDecoder2::FlushImageData()
 {
diff --git a/modules/libpr0n/src/imgContainer.cpp b/modules/libpr0n/src/imgContainer.cpp
--- a/modules/libpr0n/src/imgContainer.cpp
+++ b/modules/libpr0n/src/imgContainer.cpp
@@ -415,16 +415,18 @@ nsresult imgContainer::InternalAddFrameH
 
   nsAutoPtr<imgFrame> frame(aFrame);
 
   if (paletteData && paletteLength)
     frame->GetPaletteData(paletteData, paletteLength);
 
   frame->GetImageData(imageData, imageLength);
 
+  frame->LockImageData();
+
   mFrames.InsertElementAt(framenum, frame.forget());
   mNumFrames++;
 
   return NS_OK;
 }
                                   
 nsresult imgContainer::InternalAddFrame(PRUint32 framenum,
                                         PRInt32 aX, PRInt32 aY,
@@ -440,16 +442,21 @@ nsresult imgContainer::InternalAddFrame(
     return NS_ERROR_INVALID_ARG;
 
   nsAutoPtr<imgFrame> frame(new imgFrame());
   NS_ENSURE_TRUE(frame, NS_ERROR_OUT_OF_MEMORY);
 
   nsresult rv = frame->Init(aX, aY, aWidth, aHeight, aFormat, aPaletteDepth);
   NS_ENSURE_SUCCESS(rv, rv);
 
+  if (mFrames.Length() > 0) {
+    imgFrame *prevframe = mFrames.ElementAt(mFrames.Length() - 1);
+    prevframe->UnlockImageData();
+  }
+
   if (mFrames.Length() == 0) {
     return InternalAddFrameHelper(framenum, frame.forget(), imageData, imageLength, 
                                   paletteData, paletteLength);
   }
 
   if (mFrames.Length() == 1) {
     // Since we're about to add our second frame, initialize animation stuff
     if (!ensureAnimExists())
diff --git a/modules/libpr0n/src/imgFrame.cpp b/modules/libpr0n/src/imgFrame.cpp
--- a/modules/libpr0n/src/imgFrame.cpp
+++ b/modules/libpr0n/src/imgFrame.cpp
@@ -152,16 +152,17 @@ imgFrame::imgFrame() :
   mBlendMethod(1), /* imgIContainer::kBlendOver */
   mSinglePixel(PR_FALSE),
   mNeverUseDeviceSurface(PR_FALSE),
   mFormatChanged(PR_FALSE),
   mCompositingFailed(PR_FALSE)
 #ifdef USE_WIN_SURFACE
   , mIsDDBSurface(PR_FALSE)
 #endif
+  , mLocked(PR_FALSE)
 {
   static PRBool hasCheckedOptimize = PR_FALSE;
   if (!hasCheckedOptimize) {
     if (PR_GetEnv("MOZ_DISABLE_IMAGE_OPTIMIZE")) {
       gDisableOptimize = PR_TRUE;
     }
     hasCheckedOptimize = PR_TRUE;
   }
@@ -413,18 +414,17 @@ void imgFrame::Draw(gfxContext *aContext
   nsRefPtr<gfxASurface> surface;
   gfxImageSurface::gfxImageFormat format;
 
   NS_ASSERTION(!sourceRect.Intersect(subimage).IsEmpty(),
                "We must be allowed to sample *some* source pixels!");
 
   PRBool doTile = !imageRect.Contains(sourceRect);
   if (doPadding || doPartialDecode) {
-    gfxRect available = gfxRect(mDecoded.x, mDecoded.y, mDecoded.width, mDecoded.height) +
-      gfxPoint(aPadding.left, aPadding.top);
+    gfxRect available = gfxRect(mDecoded.x, mDecoded.y, mDecoded.width, mDecoded.height);
 
     if (!doTile && !mSinglePixel) {
       // Not tiling, and we have a surface, so we can account for
       // padding and/or a partial decode just by twiddling parameters.
       // First, update our user-space fill rect.
       sourceRect = sourceRect.Intersect(available);
       gfxMatrix imageSpaceToUserSpace = userSpaceToImageSpace;
       imageSpaceToUserSpace.Invert();
@@ -708,17 +708,17 @@ nsresult imgFrame::ImageUpdated(const ns
   mem->IsLowMemory(&lowMemory);
   if (lowMemory)
     return NS_ERROR_OUT_OF_MEMORY;
 
   mDecoded.UnionRect(mDecoded, aUpdateRect);
 
   // clamp to bounds, in case someone sends a bogus updateRect (I'm looking at
   // you, gif decoder)
-  nsIntRect boundsRect(0, 0, mSize.width, mSize.height);
+  nsIntRect boundsRect(mOffset, mSize);
   mDecoded.IntersectRect(mDecoded, boundsRect);
 
 #ifdef XP_MACOSX
   if (mQuartzSurface)
     mQuartzSurface->Flush();
 #endif
   return NS_OK;
 }
@@ -806,17 +806,23 @@ void imgFrame::GetPaletteData(PRUint32 *
     *aPalette = (PRUint32 *) mPalettedImageData;
     *length = PaletteDataLength();
   }
 }
 
 nsresult imgFrame::LockImageData()
 {
   if (mPalettedImageData)
-    return NS_OK;
+    return NS_ERROR_NOT_AVAILABLE;
+
+  NS_ABORT_IF_FALSE(!mLocked, "Trying to lock already locked image data.");
+  if (mLocked) {
+    return NS_ERROR_FAILURE;
+  }
+  mLocked = PR_TRUE;
 
   if ((mOptSurface || mSinglePixel) && !mImageSurface) {
     // Recover the pixels
     mImageSurface = new gfxImageSurface(gfxIntSize(mSize.width, mSize.height),
                                         gfxImageSurface::ImageFormatARGB32);
     if (!mImageSurface || mImageSurface->CairoStatus())
       return NS_ERROR_OUT_OF_MEMORY;
 
@@ -832,23 +838,35 @@ nsresult imgFrame::LockImageData()
 #ifdef USE_WIN_SURFACE
     mWinSurface = nsnull;
 #endif
 #ifdef XP_MACOSX
     mQuartzSurface = nsnull;
 #endif
   }
 
+  if (mImageSurface)
+    mImageSurface->Flush();
+
   return NS_OK;
 }
 
 nsresult imgFrame::UnlockImageData()
 {
   if (mPalettedImageData)
-    return NS_OK;
+    return NS_ERROR_NOT_AVAILABLE;
+
+  NS_ABORT_IF_FALSE(mLocked, "Unlocking an unlocked image!");
+  if (!mLocked) {
+    return NS_ERROR_FAILURE;
+  }
+  mLocked = PR_FALSE;
+
+  if (mImageSurface)
+    mImageSurface->MarkDirty();
 
 #ifdef XP_MACOSX
   if (mQuartzSurface)
     mQuartzSurface->Flush();
 #endif
   return NS_OK;
 }
 
@@ -895,17 +913,17 @@ PRInt32 imgFrame::GetBlendMethod() const
 
 void imgFrame::SetBlendMethod(PRInt32 aBlendMethod)
 {
   mBlendMethod = (PRInt8)aBlendMethod;
 }
 
 PRBool imgFrame::ImageComplete() const
 {
-  return mDecoded == nsIntRect(0, 0, mSize.width, mSize.height);
+  return mDecoded == nsIntRect(mOffset, mSize);
 }
 
 // A hint from the image decoders that this image has no alpha, even
 // though we created is ARGB32.  This changes our format to RGB24,
 // which in turn will cause us to Optimize() to RGB24.  Has no effect
 // after Optimize() is called, though in all cases it will be just a
 // performance win -- the pixels are still correct and have the A byte
 // set to 0xff.
diff --git a/modules/libpr0n/src/imgFrame.h b/modules/libpr0n/src/imgFrame.h
--- a/modules/libpr0n/src/imgFrame.h
+++ b/modules/libpr0n/src/imgFrame.h
@@ -167,16 +167,17 @@ private: // data
 
   gfxASurface::gfxImageFormat mFormat;
   PRInt8       mPaletteDepth;
   PRInt8       mBlendMethod;
   PRPackedBool mSinglePixel;
   PRPackedBool mNeverUseDeviceSurface;
   PRPackedBool mFormatChanged;
   PRPackedBool mCompositingFailed;
+  PRPackedBool mLocked;
 
 #ifdef XP_WIN
   PRPackedBool mIsDDBSurface;
 #endif
 
 };
 
 #endif /* imgFrame_h */