Merge branch 'master' into 816

5 files changed, 50 insertions, 9 deletions

diff --git a/image/DecoderFactory.cpp b/image/DecoderFactory.cpp
index 2085fb7c4..dffe4dc21 100644
--- a/image/DecoderFactory.cpp
+++ b/image/DecoderFactory.cpp
@@ -58,6 +58,10 @@ DecoderFactory::GetDecoderType(const char* aMimeType)
   } else if (!strcmp(aMimeType, IMAGE_BMP_MS)) {
     type = DecoderType::BMP;
 
+  // BMP_CLIPBOARD
+  } else if (!strcmp(aMimeType, IMAGE_BMP_MS_CLIPBOARD)) {
+    type = DecoderType::BMP_CLIPBOARD;
+
   // ICO
   } else if (!strcmp(aMimeType, IMAGE_ICO)) {
     type = DecoderType::ICO;
@@ -100,6 +104,9 @@ DecoderFactory::GetDecoder(DecoderType aType,
     case DecoderType::BMP:
       decoder = new nsBMPDecoder(aImage);
       break;
+    case DecoderType::BMP_CLIPBOARD:
+      decoder = new nsBMPDecoder(aImage, /* aForClipboard */ true);
+      break;
     case DecoderType::ICO:
       decoder = new nsICODecoder(aImage);
       break;
diff --git a/image/DecoderFactory.h b/image/DecoderFactory.h
index f8cf64cc6..5638789ff 100644
--- a/image/DecoderFactory.h
+++ b/image/DecoderFactory.h
@@ -34,6 +34,7 @@ enum class DecoderType
   GIF,
   JPEG,
   BMP,
+  BMP_CLIPBOARD,
   ICO,
   ICON,
   WEBP,
diff --git a/image/decoders/nsBMPDecoder.cpp b/image/decoders/nsBMPDecoder.cpp
index 42bb3486a..b93eb42b6 100644
--- a/image/decoders/nsBMPDecoder.cpp
+++ b/image/decoders/nsBMPDecoder.cpp
@@ -66,6 +66,17 @@
 //   compression, then instead of treating the pixel data as 0RGB it is treated
 //   as ARGB, but only if one or more of the A values are non-zero.
 //
+// Clipboard variants.
+// - It's the BMP format used for BMP images captured from the clipboard.
+// - It is missing the file header, containing the BM signature and the data
+//   offset. Instead the data begins after the header.
+// - If it uses BITFIELDS compression, then there is always an additional 12
+//   bytes of data after the header that must be read. In WinBMPv4+, the masks
+//   are supposed to be included in the header size, which are the values we use
+//   for decoding purposes, but there is additional three masks following the
+//   header which must be skipped to get to the pixel data.
+//
+//
 // OS/2 VERSIONS OF THE BMP FORMAT
 // -------------------------------
 // OS2-BMPv1.
@@ -168,10 +179,12 @@ static mozilla::LazyLogModule sBMPLog("BMPDecoder");
 // The length of the mBIHSize field in the info header.
 static const uint32_t BIHSIZE_FIELD_LENGTH = 4;
 
-nsBMPDecoder::nsBMPDecoder(RasterImage* aImage, State aState, size_t aLength)
+nsBMPDecoder::nsBMPDecoder(RasterImage* aImage, State aState, size_t aLength,
+                           bool aForClipboard)
   : Decoder(aImage)
   , mLexer(Transition::To(aState, aLength), Transition::TerminateSuccess())
   , mIsWithinICO(false)
+  , mIsForClipboard(aForClipboard)
   , mMayHaveTransparency(false)
   , mDoesHaveTransparency(false)
   , mNumColors(0)
@@ -185,15 +198,19 @@ nsBMPDecoder::nsBMPDecoder(RasterImage* aImage, State aState, size_t aLength)
 {
 }
 
-// Constructor for normal BMP files.
-nsBMPDecoder::nsBMPDecoder(RasterImage* aImage)
-  : nsBMPDecoder(aImage, State::FILE_HEADER, FILE_HEADER_LENGTH)
+// Constructor for normal BMP files or from the clipboard.
+nsBMPDecoder::nsBMPDecoder(RasterImage* aImage, bool aForClipboard)
+  : nsBMPDecoder(aImage,
+                 aForClipboard ? State::INFO_HEADER_SIZE : State::FILE_HEADER,
+                 aForClipboard ? BIHSIZE_FIELD_LENGTH : FILE_HEADER_LENGTH,
+                 aForClipboard)
 {
 }
 
 // Constructor used for WinBMPv3-ICO files, which lack a file header.
 nsBMPDecoder::nsBMPDecoder(RasterImage* aImage, uint32_t aDataOffset)
-  : nsBMPDecoder(aImage, State::INFO_HEADER_SIZE, BIHSIZE_FIELD_LENGTH)
+  : nsBMPDecoder(aImage, State::INFO_HEADER_SIZE, BIHSIZE_FIELD_LENGTH,
+                 /* aForClipboard */ false)
 {
   SetIsWithinICO();
 
@@ -598,6 +615,13 @@ nsBMPDecoder::ReadInfoHeaderRest(const char* aData, size_t aLength)
       // Bitfields are present in the info header, so we can read them
       // immediately.
       mBitFields.ReadFromHeader(aData + 36, /* aReadAlpha = */ true);
+
+      // If this came from the clipboard, then we know that even if the header
+      // explicitly includes the bitfield masks, we need to add an additional
+      // offset for the start of the RGB data.
+      if (mIsForClipboard) {
+        mH.mDataOffset += BitFields::LENGTH;
+      }
     } else {
       // Bitfields are present after the info header, so we will read them in
       // ReadBitfields().
@@ -712,6 +736,12 @@ nsBMPDecoder::ReadColorTable(const char* aData, size_t aLength)
     aData += mBytesPerColor;
   }
 
+  // If we are decoding a BMP from the clipboard, we did not know the data
+  // offset in advance. It is defined as just after the header and color table.
+  if (mIsForClipboard) {
+    mH.mDataOffset += mPreGapLength;
+  }
+
   // We know how many bytes we've read so far (mPreGapLength) and we know the
   // offset of the pixel data (mH.mDataOffset), so we can determine the length
   // of the gap (possibly zero) between the color table and the pixel data.
diff --git a/image/decoders/nsBMPDecoder.h b/image/decoders/nsBMPDecoder.h
index 0cf2af689..4b9568487 100644
--- a/image/decoders/nsBMPDecoder.h
+++ b/image/decoders/nsBMPDecoder.h
@@ -164,14 +164,14 @@ private:
     RLE_ABSOLUTE
   };
 
-  // This is the constructor used for normal BMP images.
-  explicit nsBMPDecoder(RasterImage* aImage);
+  // This is the constructor used for normal and clipboard BMP images.
+  explicit nsBMPDecoder(RasterImage* aImage, bool aForClipboard = false);
 
   // This is the constructor used for BMP resources in ICO images.
   nsBMPDecoder(RasterImage* aImage, uint32_t aDataOffset);
 
   // Helper constructor called by the other two.
-  nsBMPDecoder(RasterImage* aImage, State aState, size_t aLength);
+  nsBMPDecoder(RasterImage* aImage, State aState, size_t aLength, bool aForClipboard);
 
   int32_t AbsoluteHeight() const { return abs(mH.mHeight); }
 
@@ -198,6 +198,9 @@ private:
   // If the BMP is within an ICO file our treatment of it differs slightly.
   bool mIsWithinICO;
 
+  // If the BMP is decoded from the clipboard, we start with a data offset.
+  bool mIsForClipboard;
+
   bmp::BitFields mBitFields;
 
   // Might the image have transparency? Determined from the headers during
diff --git a/image/imgFrame.cpp b/image/imgFrame.cpp
index c9f44181d..d982c17c4 100644
--- a/image/imgFrame.cpp
+++ b/image/imgFrame.cpp
@@ -161,13 +161,13 @@ imgFrame::imgFrame()
   : mMonitor("imgFrame")
   , mDecoded(0, 0, 0, 0)
   , mLockCount(0)
+  , mHasNoAlpha(false)
   , mAborted(false)
   , mFinished(false)
   , mOptimizable(false)
   , mTimeout(FrameTimeout::FromRawMilliseconds(100))
   , mDisposalMethod(DisposalMethod::NOT_SPECIFIED)
   , mBlendMethod(BlendMethod::OVER)
-  , mHasNoAlpha(false)
   , mPalettedImageData(nullptr)
   , mPaletteDepth(0)
   , mNonPremult(false)