Add m-esr52 at 52.6.0

1 files changed, 1113 insertions, 0 deletions

diff --git a/image/decoders/nsPNGDecoder.cpp b/image/decoders/nsPNGDecoder.cpp
new file mode 100644
index 000000000..0f385b339
--- /dev/null
+++ b/image/decoders/nsPNGDecoder.cpp
@@ -0,0 +1,1113 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ImageLogging.h" // Must appear first
+#include "nsPNGDecoder.h"
+
+#include <algorithm>
+#include <cstdint>
+
+#include "gfxColor.h"
+#include "gfxPlatform.h"
+#include "imgFrame.h"
+#include "nsColor.h"
+#include "nsIInputStream.h"
+#include "nsMemory.h"
+#include "nsRect.h"
+#include "nspr.h"
+#include "png.h"
+#include "RasterImage.h"
+#include "SurfacePipeFactory.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/Telemetry.h"
+
+using namespace mozilla::gfx;
+
+using std::min;
+
+namespace mozilla {
+namespace image {
+
+static LazyLogModule sPNGLog("PNGDecoder");
+static LazyLogModule sPNGDecoderAccountingLog("PNGDecoderAccounting");
+
+// limit image dimensions (bug #251381, #591822, #967656, and #1283961)
+#ifndef MOZ_PNG_MAX_WIDTH
+#  define MOZ_PNG_MAX_WIDTH 0x7fffffff // Unlimited
+#endif
+#ifndef MOZ_PNG_MAX_HEIGHT
+#  define MOZ_PNG_MAX_HEIGHT 0x7fffffff // Unlimited
+#endif
+
+nsPNGDecoder::AnimFrameInfo::AnimFrameInfo()
+ : mDispose(DisposalMethod::KEEP)
+ , mBlend(BlendMethod::OVER)
+ , mTimeout(0)
+{ }
+
+#ifdef PNG_APNG_SUPPORTED
+
+int32_t GetNextFrameDelay(png_structp aPNG, png_infop aInfo)
+{
+  // Delay, in seconds, is delayNum / delayDen.
+  png_uint_16 delayNum = png_get_next_frame_delay_num(aPNG, aInfo);
+  png_uint_16 delayDen = png_get_next_frame_delay_den(aPNG, aInfo);
+
+  if (delayNum == 0) {
+    return 0; // SetFrameTimeout() will set to a minimum.
+  }
+
+  if (delayDen == 0) {
+    delayDen = 100; // So says the APNG spec.
+  }
+
+  // Need to cast delay_num to float to have a proper division and
+  // the result to int to avoid a compiler warning.
+  return static_cast<int32_t>(static_cast<double>(delayNum) * 1000 / delayDen);
+}
+
+nsPNGDecoder::AnimFrameInfo::AnimFrameInfo(png_structp aPNG, png_infop aInfo)
+ : mDispose(DisposalMethod::KEEP)
+ , mBlend(BlendMethod::OVER)
+ , mTimeout(0)
+{
+  png_byte dispose_op = png_get_next_frame_dispose_op(aPNG, aInfo);
+  png_byte blend_op = png_get_next_frame_blend_op(aPNG, aInfo);
+
+  if (dispose_op == PNG_DISPOSE_OP_PREVIOUS) {
+    mDispose = DisposalMethod::RESTORE_PREVIOUS;
+  } else if (dispose_op == PNG_DISPOSE_OP_BACKGROUND) {
+    mDispose = DisposalMethod::CLEAR;
+  } else {
+    mDispose = DisposalMethod::KEEP;
+  }
+
+  if (blend_op == PNG_BLEND_OP_SOURCE) {
+    mBlend = BlendMethod::SOURCE;
+  } else {
+    mBlend = BlendMethod::OVER;
+  }
+
+  mTimeout = GetNextFrameDelay(aPNG, aInfo);
+}
+#endif
+
+// First 8 bytes of a PNG file
+const uint8_t
+nsPNGDecoder::pngSignatureBytes[] = { 137, 80, 78, 71, 13, 10, 26, 10 };
+
+nsPNGDecoder::nsPNGDecoder(RasterImage* aImage)
+ : Decoder(aImage)
+ , mLexer(Transition::ToUnbuffered(State::FINISHED_PNG_DATA,
+                                   State::PNG_DATA,
+                                   SIZE_MAX),
+          Transition::TerminateSuccess())
+ , mNextTransition(Transition::ContinueUnbuffered(State::PNG_DATA))
+ , mLastChunkLength(0)
+ , mPNG(nullptr)
+ , mInfo(nullptr)
+ , mCMSLine(nullptr)
+ , interlacebuf(nullptr)
+ , mInProfile(nullptr)
+ , mTransform(nullptr)
+ , format(gfx::SurfaceFormat::UNKNOWN)
+ , mCMSMode(0)
+ , mChannels(0)
+ , mPass(0)
+ , mFrameIsHidden(false)
+ , mDisablePremultipliedAlpha(false)
+ , mNumFrames(0)
+{ }
+
+nsPNGDecoder::~nsPNGDecoder()
+{
+  if (mPNG) {
+    png_destroy_read_struct(&mPNG, mInfo ? &mInfo : nullptr, nullptr);
+  }
+  if (mCMSLine) {
+    free(mCMSLine);
+  }
+  if (interlacebuf) {
+    free(interlacebuf);
+  }
+  if (mInProfile) {
+    qcms_profile_release(mInProfile);
+
+    // mTransform belongs to us only if mInProfile is non-null
+    if (mTransform) {
+      qcms_transform_release(mTransform);
+    }
+  }
+}
+
+nsPNGDecoder::TransparencyType
+nsPNGDecoder::GetTransparencyType(SurfaceFormat aFormat,
+                                  const IntRect& aFrameRect)
+{
+  // Check if the image has a transparent color in its palette.
+  if (aFormat == SurfaceFormat::B8G8R8A8) {
+    return TransparencyType::eAlpha;
+  }
+  if (!aFrameRect.IsEqualEdges(FullFrame())) {
+    MOZ_ASSERT(HasAnimation());
+    return TransparencyType::eFrameRect;
+  }
+
+  return TransparencyType::eNone;
+}
+
+void
+nsPNGDecoder::PostHasTransparencyIfNeeded(TransparencyType aTransparencyType)
+{
+  switch (aTransparencyType) {
+    case TransparencyType::eNone:
+      return;
+
+    case TransparencyType::eAlpha:
+      PostHasTransparency();
+      return;
+
+    case TransparencyType::eFrameRect:
+      // If the first frame of animated image doesn't draw into the whole image,
+      // then record that it is transparent. For subsequent frames, this doesn't
+      // affect transparency, because they're composited on top of all previous
+      // frames.
+      if (mNumFrames == 0) {
+        PostHasTransparency();
+      }
+      return;
+  }
+}
+
+// CreateFrame() is used for both simple and animated images.
+nsresult
+nsPNGDecoder::CreateFrame(const FrameInfo& aFrameInfo)
+{
+  MOZ_ASSERT(HasSize());
+  MOZ_ASSERT(!IsMetadataDecode());
+
+  // Check if we have transparency, and send notifications if needed.
+  auto transparency = GetTransparencyType(aFrameInfo.mFormat,
+                                          aFrameInfo.mFrameRect);
+  PostHasTransparencyIfNeeded(transparency);
+  SurfaceFormat format = transparency == TransparencyType::eNone
+                       ? SurfaceFormat::B8G8R8X8
+                       : SurfaceFormat::B8G8R8A8;
+
+  // Make sure there's no animation or padding if we're downscaling.
+  MOZ_ASSERT_IF(Size() != OutputSize(), mNumFrames == 0);
+  MOZ_ASSERT_IF(Size() != OutputSize(), !GetImageMetadata().HasAnimation());
+  MOZ_ASSERT_IF(Size() != OutputSize(),
+                transparency != TransparencyType::eFrameRect);
+
+  // If this image is interlaced, we can display better quality intermediate
+  // results to the user by post processing them with ADAM7InterpolatingFilter.
+  SurfacePipeFlags pipeFlags = aFrameInfo.mIsInterlaced
+                             ? SurfacePipeFlags::ADAM7_INTERPOLATE
+                             : SurfacePipeFlags();
+
+  if (mNumFrames == 0) {
+    // The first frame may be displayed progressively.
+    pipeFlags |= SurfacePipeFlags::PROGRESSIVE_DISPLAY;
+  }
+
+  Maybe<SurfacePipe> pipe =
+    SurfacePipeFactory::CreateSurfacePipe(this, mNumFrames, Size(),
+                                          OutputSize(), aFrameInfo.mFrameRect,
+                                          format, pipeFlags);
+
+  if (!pipe) {
+    mPipe = SurfacePipe();
+    return NS_ERROR_FAILURE;
+  }
+
+  mPipe = Move(*pipe);
+
+  mFrameRect = aFrameInfo.mFrameRect;
+  mPass = 0;
+
+  MOZ_LOG(sPNGDecoderAccountingLog, LogLevel::Debug,
+         ("PNGDecoderAccounting: nsPNGDecoder::CreateFrame -- created "
+          "image frame with %dx%d pixels for decoder %p",
+          mFrameRect.width, mFrameRect.height, this));
+
+#ifdef PNG_APNG_SUPPORTED
+  if (png_get_valid(mPNG, mInfo, PNG_INFO_acTL)) {
+    mAnimInfo = AnimFrameInfo(mPNG, mInfo);
+
+    if (mAnimInfo.mDispose == DisposalMethod::CLEAR) {
+      // We may have to display the background under this image during
+      // animation playback, so we regard it as transparent.
+      PostHasTransparency();
+    }
+  }
+#endif
+
+  return NS_OK;
+}
+
+// set timeout and frame disposal method for the current frame
+void
+nsPNGDecoder::EndImageFrame()
+{
+  if (mFrameIsHidden) {
+    return;
+  }
+
+  mNumFrames++;
+
+  Opacity opacity = Opacity::SOME_TRANSPARENCY;
+  if (format == gfx::SurfaceFormat::B8G8R8X8) {
+    opacity = Opacity::FULLY_OPAQUE;
+  }
+
+  PostFrameStop(opacity, mAnimInfo.mDispose,
+                FrameTimeout::FromRawMilliseconds(mAnimInfo.mTimeout),
+                mAnimInfo.mBlend, Some(mFrameRect));
+}
+
+nsresult
+nsPNGDecoder::InitInternal()
+{
+  mCMSMode = gfxPlatform::GetCMSMode();
+  if (GetSurfaceFlags() & SurfaceFlags::NO_COLORSPACE_CONVERSION) {
+    mCMSMode = eCMSMode_Off;
+  }
+  mDisablePremultipliedAlpha =
+    bool(GetSurfaceFlags() & SurfaceFlags::NO_PREMULTIPLY_ALPHA);
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+  static png_byte color_chunks[]=
+       { 99,  72,  82,  77, '\0',   // cHRM
+        105,  67,  67,  80, '\0'};  // iCCP
+  static png_byte unused_chunks[]=
+       { 98,  75,  71,  68, '\0',   // bKGD
+        104,  73,  83,  84, '\0',   // hIST
+        105,  84,  88, 116, '\0',   // iTXt
+        111,  70,  70, 115, '\0',   // oFFs
+        112,  67,  65,  76, '\0',   // pCAL
+        115,  67,  65,  76, '\0',   // sCAL
+        112,  72,  89, 115, '\0',   // pHYs
+        115,  66,  73,  84, '\0',   // sBIT
+        115,  80,  76,  84, '\0',   // sPLT
+        116,  69,  88, 116, '\0',   // tEXt
+        116,  73,  77,  69, '\0',   // tIME
+        122,  84,  88, 116, '\0'};  // zTXt
+#endif
+
+  // Initialize the container's source image header
+  // Always decode to 24 bit pixdepth
+
+  mPNG = png_create_read_struct(PNG_LIBPNG_VER_STRING,
+                                nullptr, nsPNGDecoder::error_callback,
+                                nsPNGDecoder::warning_callback);
+  if (!mPNG) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  mInfo = png_create_info_struct(mPNG);
+  if (!mInfo) {
+    png_destroy_read_struct(&mPNG, nullptr, nullptr);
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+  // Ignore unused chunks
+  if (mCMSMode == eCMSMode_Off || IsMetadataDecode()) {
+    png_set_keep_unknown_chunks(mPNG, 1, color_chunks, 2);
+  }
+
+  png_set_keep_unknown_chunks(mPNG, 1, unused_chunks,
+                              (int)sizeof(unused_chunks)/5);
+#endif
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+  png_set_user_limits(mPNG, MOZ_PNG_MAX_WIDTH, MOZ_PNG_MAX_HEIGHT);
+  if (mCMSMode != eCMSMode_Off) {
+    png_set_chunk_malloc_max(mPNG, 4000000L);
+  }
+#endif
+
+#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
+  // Disallow palette-index checking, for speed; we would ignore the warning
+  // anyhow.  This feature was added at libpng version 1.5.10 and is disabled
+  // in the embedded libpng but enabled by default in the system libpng.  This
+  // call also disables it in the system libpng, for decoding speed.
+  // Bug #745202.
+  png_set_check_for_invalid_index(mPNG, 0);
+#endif
+
+#ifdef PNG_SET_OPTION_SUPPORTED
+#if defined(PNG_sRGB_PROFILE_CHECKS) && PNG_sRGB_PROFILE_CHECKS >= 0
+  // Skip checking of sRGB ICC profiles
+  png_set_option(mPNG, PNG_SKIP_sRGB_CHECK_PROFILE, PNG_OPTION_ON);
+#endif
+
+#ifdef PNG_MAXIMUM_INFLATE_WINDOW
+  // Force a larger zlib inflate window as some images in the wild have
+  // incorrectly set metadata (specifically CMF bits) which prevent us from
+  // decoding them otherwise.
+  png_set_option(mPNG, PNG_MAXIMUM_INFLATE_WINDOW, PNG_OPTION_ON);
+#endif
+#endif
+
+  // use this as libpng "progressive pointer" (retrieve in callbacks)
+  png_set_progressive_read_fn(mPNG, static_cast<png_voidp>(this),
+                              nsPNGDecoder::info_callback,
+                              nsPNGDecoder::row_callback,
+                              nsPNGDecoder::end_callback);
+
+  return NS_OK;
+}
+
+LexerResult
+nsPNGDecoder::DoDecode(SourceBufferIterator& aIterator, IResumable* aOnResume)
+{
+  MOZ_ASSERT(!HasError(), "Shouldn't call DoDecode after error!");
+
+  return mLexer.Lex(aIterator, aOnResume,
+                    [=](State aState, const char* aData, size_t aLength) {
+    switch (aState) {
+      case State::PNG_DATA:
+        return ReadPNGData(aData, aLength);
+      case State::FINISHED_PNG_DATA:
+        return FinishedPNGData();
+    }
+    MOZ_CRASH("Unknown State");
+  });
+}
+
+LexerTransition<nsPNGDecoder::State>
+nsPNGDecoder::ReadPNGData(const char* aData, size_t aLength)
+{
+  // If we were waiting until after returning from a yield to call
+  // CreateFrame(), call it now.
+  if (mNextFrameInfo) {
+    if (NS_FAILED(CreateFrame(*mNextFrameInfo))) {
+      return Transition::TerminateFailure();
+    }
+
+    MOZ_ASSERT(mImageData, "Should have a buffer now");
+    mNextFrameInfo = Nothing();
+  }
+
+  // libpng uses setjmp/longjmp for error handling.
+  if (setjmp(png_jmpbuf(mPNG))) {
+    return Transition::TerminateFailure();
+  }
+
+  // Pass the data off to libpng.
+  mLastChunkLength = aLength;
+  mNextTransition = Transition::ContinueUnbuffered(State::PNG_DATA);
+  png_process_data(mPNG, mInfo,
+                   reinterpret_cast<unsigned char*>(const_cast<char*>((aData))),
+                   aLength);
+
+  // Make sure that we've reached a terminal state if decoding is done.
+  MOZ_ASSERT_IF(GetDecodeDone(), mNextTransition.NextStateIsTerminal());
+  MOZ_ASSERT_IF(HasError(), mNextTransition.NextStateIsTerminal());
+
+  // Continue with whatever transition the callback code requested. We
+  // initialized this to Transition::ContinueUnbuffered(State::PNG_DATA) above,
+  // so by default we just continue the unbuffered read.
+  return mNextTransition;
+}
+
+LexerTransition<nsPNGDecoder::State>
+nsPNGDecoder::FinishedPNGData()
+{
+  // Since we set up an unbuffered read for SIZE_MAX bytes, if we actually read
+  // all that data something is really wrong.
+  MOZ_ASSERT_UNREACHABLE("Read the entire address space?");
+  return Transition::TerminateFailure();
+}
+
+// Sets up gamma pre-correction in libpng before our callback gets called.
+// We need to do this if we don't end up with a CMS profile.
+static void
+PNGDoGammaCorrection(png_structp png_ptr, png_infop info_ptr)
+{
+  double aGamma;
+
+  if (png_get_gAMA(png_ptr, info_ptr, &aGamma)) {
+    if ((aGamma <= 0.0) || (aGamma > 21474.83)) {
+      aGamma = 0.45455;
+      png_set_gAMA(png_ptr, info_ptr, aGamma);
+    }
+    png_set_gamma(png_ptr, 2.2, aGamma);
+  } else {
+    png_set_gamma(png_ptr, 2.2, 0.45455);
+  }
+}
+
+// Adapted from http://www.littlecms.com/pngchrm.c example code
+static qcms_profile*
+PNGGetColorProfile(png_structp png_ptr, png_infop info_ptr,
+                   int color_type, qcms_data_type* inType, uint32_t* intent)
+{
+  qcms_profile* profile = nullptr;
+  *intent = QCMS_INTENT_PERCEPTUAL; // Our default
+
+  // First try to see if iCCP chunk is present
+  if (png_get_valid(png_ptr, info_ptr, PNG_INFO_iCCP)) {
+    png_uint_32 profileLen;
+    png_bytep profileData;
+    png_charp profileName;
+    int compression;
+
+    png_get_iCCP(png_ptr, info_ptr, &profileName, &compression,
+                 &profileData, &profileLen);
+
+    profile = qcms_profile_from_memory((char*)profileData, profileLen);
+    if (profile) {
+      uint32_t profileSpace = qcms_profile_get_color_space(profile);
+
+      bool mismatch = false;
+      if (color_type & PNG_COLOR_MASK_COLOR) {
+        if (profileSpace != icSigRgbData) {
+          mismatch = true;
+        }
+      } else {
+        if (profileSpace == icSigRgbData) {
+          png_set_gray_to_rgb(png_ptr);
+        } else if (profileSpace != icSigGrayData) {
+          mismatch = true;
+        }
+      }
+
+      if (mismatch) {
+        qcms_profile_release(profile);
+        profile = nullptr;
+      } else {
+        *intent = qcms_profile_get_rendering_intent(profile);
+      }
+    }
+  }
+
+  // Check sRGB chunk
+  if (!profile && png_get_valid(png_ptr, info_ptr, PNG_INFO_sRGB)) {
+    profile = qcms_profile_sRGB();
+
+    if (profile) {
+      int fileIntent;
+      png_set_gray_to_rgb(png_ptr);
+      png_get_sRGB(png_ptr, info_ptr, &fileIntent);
+      uint32_t map[] = { QCMS_INTENT_PERCEPTUAL,
+                         QCMS_INTENT_RELATIVE_COLORIMETRIC,
+                         QCMS_INTENT_SATURATION,
+                         QCMS_INTENT_ABSOLUTE_COLORIMETRIC };
+      *intent = map[fileIntent];
+    }
+  }
+
+  // Check gAMA/cHRM chunks
+  if (!profile &&
+       png_get_valid(png_ptr, info_ptr, PNG_INFO_gAMA) &&
+       png_get_valid(png_ptr, info_ptr, PNG_INFO_cHRM)) {
+    qcms_CIE_xyYTRIPLE primaries;
+    qcms_CIE_xyY whitePoint;
+
+    png_get_cHRM(png_ptr, info_ptr,
+                 &whitePoint.x, &whitePoint.y,
+                 &primaries.red.x,   &primaries.red.y,
+                 &primaries.green.x, &primaries.green.y,
+                 &primaries.blue.x,  &primaries.blue.y);
+    whitePoint.Y =
+      primaries.red.Y = primaries.green.Y = primaries.blue.Y = 1.0;
+
+    double gammaOfFile;
+
+    png_get_gAMA(png_ptr, info_ptr, &gammaOfFile);
+
+    profile = qcms_profile_create_rgb_with_gamma(whitePoint, primaries,
+                                                 1.0/gammaOfFile);
+
+    if (profile) {
+      png_set_gray_to_rgb(png_ptr);
+    }
+  }
+
+  if (profile) {
+    uint32_t profileSpace = qcms_profile_get_color_space(profile);
+    if (profileSpace == icSigGrayData) {
+      if (color_type & PNG_COLOR_MASK_ALPHA) {
+        *inType = QCMS_DATA_GRAYA_8;
+      } else {
+        *inType = QCMS_DATA_GRAY_8;
+      }
+    } else {
+      if (color_type & PNG_COLOR_MASK_ALPHA ||
+          png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
+        *inType = QCMS_DATA_RGBA_8;
+      } else {
+        *inType = QCMS_DATA_RGB_8;
+      }
+    }
+  }
+
+  return profile;
+}
+
+void
+nsPNGDecoder::info_callback(png_structp png_ptr, png_infop info_ptr)
+{
+  png_uint_32 width, height;
+  int bit_depth, color_type, interlace_type, compression_type, filter_type;
+  unsigned int channels;
+
+  png_bytep trans = nullptr;
+  int num_trans = 0;
+
+  nsPNGDecoder* decoder =
+               static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
+
+  // Always decode to 24-bit RGB or 32-bit RGBA
+  png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+               &interlace_type, &compression_type, &filter_type);
+
+  const IntRect frameRect(0, 0, width, height);
+
+  // Post our size to the superclass
+  decoder->PostSize(frameRect.width, frameRect.height);
+  if (decoder->HasError()) {
+    // Setting the size led to an error.
+    png_error(decoder->mPNG, "Sizing error");
+  }
+
+  if (color_type == PNG_COLOR_TYPE_PALETTE) {
+    png_set_expand(png_ptr);
+  }
+
+  if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+    png_set_expand(png_ptr);
+  }
+
+  if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) {
+    png_color_16p trans_values;
+    png_get_tRNS(png_ptr, info_ptr, &trans, &num_trans, &trans_values);
+    // libpng doesn't reject a tRNS chunk with out-of-range samples
+    // so we check it here to avoid setting up a useless opacity
+    // channel or producing unexpected transparent pixels (bug #428045)
+    if (bit_depth < 16) {
+      png_uint_16 sample_max = (1 << bit_depth) - 1;
+      if ((color_type == PNG_COLOR_TYPE_GRAY &&
+           trans_values->gray > sample_max) ||
+           (color_type == PNG_COLOR_TYPE_RGB &&
+           (trans_values->red > sample_max ||
+           trans_values->green > sample_max ||
+           trans_values->blue > sample_max))) {
+        // clear the tRNS valid flag and release tRNS memory
+        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
+        num_trans = 0;
+      }
+    }
+    if (num_trans != 0) {
+      png_set_expand(png_ptr);
+    }
+  }
+
+  if (bit_depth == 16) {
+    png_set_scale_16(png_ptr);
+  }
+
+  qcms_data_type inType = QCMS_DATA_RGBA_8;
+  uint32_t intent = -1;
+  uint32_t pIntent;
+  if (decoder->mCMSMode != eCMSMode_Off) {
+    intent = gfxPlatform::GetRenderingIntent();
+    decoder->mInProfile = PNGGetColorProfile(png_ptr, info_ptr,
+                                             color_type, &inType, &pIntent);
+    // If we're not mandating an intent, use the one from the image.
+    if (intent == uint32_t(-1)) {
+      intent = pIntent;
+    }
+  }
+  if (decoder->mInProfile && gfxPlatform::GetCMSOutputProfile()) {
+    qcms_data_type outType;
+
+    if (color_type & PNG_COLOR_MASK_ALPHA || num_trans) {
+      outType = QCMS_DATA_RGBA_8;
+    } else {
+      outType = QCMS_DATA_RGB_8;
+    }
+
+    decoder->mTransform = qcms_transform_create(decoder->mInProfile,
+                                           inType,
+                                           gfxPlatform::GetCMSOutputProfile(),
+                                           outType,
+                                           (qcms_intent)intent);
+  } else {
+    png_set_gray_to_rgb(png_ptr);
+
+    // only do gamma correction if CMS isn't entirely disabled
+    if (decoder->mCMSMode != eCMSMode_Off) {
+      PNGDoGammaCorrection(png_ptr, info_ptr);
+    }
+
+    if (decoder->mCMSMode == eCMSMode_All) {
+      if (color_type & PNG_COLOR_MASK_ALPHA || num_trans) {
+        decoder->mTransform = gfxPlatform::GetCMSRGBATransform();
+      } else {
+        decoder->mTransform = gfxPlatform::GetCMSRGBTransform();
+      }
+    }
+  }
+
+  // Let libpng expand interlaced images.
+  const bool isInterlaced = interlace_type == PNG_INTERLACE_ADAM7;
+  if (isInterlaced) {
+    png_set_interlace_handling(png_ptr);
+  }
+
+  // now all of those things we set above are used to update various struct
+  // members and whatnot, after which we can get channels, rowbytes, etc.
+  png_read_update_info(png_ptr, info_ptr);
+  decoder->mChannels = channels = png_get_channels(png_ptr, info_ptr);
+
+  //---------------------------------------------------------------//
+  // copy PNG info into imagelib structs (formerly png_set_dims()) //
+  //---------------------------------------------------------------//
+
+  if (channels == 1 || channels == 3) {
+    decoder->format = gfx::SurfaceFormat::B8G8R8X8;
+  } else if (channels == 2 || channels == 4) {
+    decoder->format = gfx::SurfaceFormat::B8G8R8A8;
+  } else {
+    png_error(decoder->mPNG, "Invalid number of channels");
+  }
+
+#ifdef PNG_APNG_SUPPORTED
+  bool isAnimated = png_get_valid(png_ptr, info_ptr, PNG_INFO_acTL);
+  if (isAnimated) {
+    int32_t rawTimeout = GetNextFrameDelay(png_ptr, info_ptr);
+    decoder->PostIsAnimated(FrameTimeout::FromRawMilliseconds(rawTimeout));
+
+    if (decoder->Size() != decoder->OutputSize() &&
+        !decoder->IsFirstFrameDecode()) {
+      MOZ_ASSERT_UNREACHABLE("Doing downscale-during-decode "
+                             "for an animated image?");
+      png_error(decoder->mPNG, "Invalid downscale attempt"); // Abort decode.
+    }
+  }
+#endif
+
+  if (decoder->IsMetadataDecode()) {
+    // If we are animated then the first frame rect is either:
+    // 1) the whole image if the IDAT chunk is part of the animation
+    // 2) the frame rect of the first fDAT chunk otherwise.
+    // If we are not animated then we want to make sure to call
+    // PostHasTransparency in the metadata decode if we need to. So it's
+    // okay to pass IntRect(0, 0, width, height) here for animated images;
+    // they will call with the proper first frame rect in the full decode.
+    auto transparency = decoder->GetTransparencyType(decoder->format,
+                                                     frameRect);
+    decoder->PostHasTransparencyIfNeeded(transparency);
+
+    // We have the metadata we're looking for, so stop here, before we allocate
+    // buffers below.
+    return decoder->DoTerminate(png_ptr, TerminalState::SUCCESS);
+  }
+
+#ifdef PNG_APNG_SUPPORTED
+  if (isAnimated) {
+    png_set_progressive_frame_fn(png_ptr, nsPNGDecoder::frame_info_callback,
+                                 nullptr);
+  }
+
+  if (png_get_first_frame_is_hidden(png_ptr, info_ptr)) {
+    decoder->mFrameIsHidden = true;
+  } else {
+#endif
+    nsresult rv = decoder->CreateFrame(FrameInfo{ decoder->format,
+                                                  frameRect,
+                                                  isInterlaced });
+    if (NS_FAILED(rv)) {
+      png_error(decoder->mPNG, "CreateFrame failed");
+    }
+    MOZ_ASSERT(decoder->mImageData, "Should have a buffer now");
+#ifdef PNG_APNG_SUPPORTED
+  }
+#endif
+
+  if (decoder->mTransform && (channels <= 2 || isInterlaced)) {
+    uint32_t bpp[] = { 0, 3, 4, 3, 4 };
+    decoder->mCMSLine =
+      static_cast<uint8_t*>(malloc(bpp[channels] * frameRect.width));
+    if (!decoder->mCMSLine) {
+      png_error(decoder->mPNG, "malloc of mCMSLine failed");
+    }
+  }
+
+  if (interlace_type == PNG_INTERLACE_ADAM7) {
+    if (frameRect.height < INT32_MAX / (frameRect.width * int32_t(channels))) {
+      const size_t bufferSize = channels * frameRect.width * frameRect.height;
+      decoder->interlacebuf = static_cast<uint8_t*>(malloc(bufferSize));
+    }
+    if (!decoder->interlacebuf) {
+      png_error(decoder->mPNG, "malloc of interlacebuf failed");
+    }
+  }
+}
+
+void
+nsPNGDecoder::PostInvalidationIfNeeded()
+{
+  Maybe<SurfaceInvalidRect> invalidRect = mPipe.TakeInvalidRect();
+  if (!invalidRect) {
+    return;
+  }
+
+  PostInvalidation(invalidRect->mInputSpaceRect,
+                   Some(invalidRect->mOutputSpaceRect));
+}
+
+static NextPixel<uint32_t>
+PackRGBPixelAndAdvance(uint8_t*& aRawPixelInOut)
+{
+  const uint32_t pixel =
+    gfxPackedPixel(0xFF, aRawPixelInOut[0], aRawPixelInOut[1],
+                   aRawPixelInOut[2]);
+  aRawPixelInOut += 3;
+  return AsVariant(pixel);
+}
+
+static NextPixel<uint32_t>
+PackRGBAPixelAndAdvance(uint8_t*& aRawPixelInOut)
+{
+  const uint32_t pixel =
+    gfxPackedPixel(aRawPixelInOut[3], aRawPixelInOut[0],
+                   aRawPixelInOut[1], aRawPixelInOut[2]);
+  aRawPixelInOut += 4;
+  return AsVariant(pixel);
+}
+
+static NextPixel<uint32_t>
+PackUnpremultipliedRGBAPixelAndAdvance(uint8_t*& aRawPixelInOut)
+{
+  const uint32_t pixel =
+    gfxPackedPixelNoPreMultiply(aRawPixelInOut[3], aRawPixelInOut[0],
+                                aRawPixelInOut[1], aRawPixelInOut[2]);
+  aRawPixelInOut += 4;
+  return AsVariant(pixel);
+}
+
+void
+nsPNGDecoder::row_callback(png_structp png_ptr, png_bytep new_row,
+                           png_uint_32 row_num, int pass)
+{
+  /* libpng comments:
+   *
+   * This function is called for every row in the image.  If the
+   * image is interlacing, and you turned on the interlace handler,
+   * this function will be called for every row in every pass.
+   * Some of these rows will not be changed from the previous pass.
+   * When the row is not changed, the new_row variable will be
+   * nullptr. The rows and passes are called in order, so you don't
+   * really need the row_num and pass, but I'm supplying them
+   * because it may make your life easier.
+   *
+   * For the non-nullptr rows of interlaced images, you must call
+   * png_progressive_combine_row() passing in the row and the
+   * old row.  You can call this function for nullptr rows (it will
+   * just return) and for non-interlaced images (it just does the
+   * memcpy for you) if it will make the code easier.  Thus, you
+   * can just do this for all cases:
+   *
+   *    png_progressive_combine_row(png_ptr, old_row, new_row);
+   *
+   * where old_row is what was displayed for previous rows.  Note
+   * that the first pass (pass == 0 really) will completely cover
+   * the old row, so the rows do not have to be initialized.  After
+   * the first pass (and only for interlaced images), you will have
+   * to pass the current row, and the function will combine the
+   * old row and the new row.
+   */
+  nsPNGDecoder* decoder =
+    static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
+
+  if (decoder->mFrameIsHidden) {
+    return;  // Skip this frame.
+  }
+
+  MOZ_ASSERT_IF(decoder->IsFirstFrameDecode(), decoder->mNumFrames == 0);
+
+  while (pass > decoder->mPass) {
+    // Advance to the next pass. We may have to do this multiple times because
+    // libpng will skip passes if the image is so small that no pixels have
+    // changed on a given pass, but ADAM7InterpolatingFilter needs to be reset
+    // once for every pass to perform interpolation properly.
+    decoder->mPipe.ResetToFirstRow();
+    decoder->mPass++;
+  }
+
+  const png_uint_32 height =
+    static_cast<png_uint_32>(decoder->mFrameRect.height);
+
+  if (row_num >= height) {
+    // Bail if we receive extra rows. This is especially important because if we
+    // didn't, we might overflow the deinterlacing buffer.
+    MOZ_ASSERT_UNREACHABLE("libpng producing extra rows?");
+    return;
+  }
+
+  // Note that |new_row| may be null here, indicating that this is an interlaced
+  // image and |row_callback| is being called for a row that hasn't changed.
+  MOZ_ASSERT_IF(!new_row, decoder->interlacebuf);
+  uint8_t* rowToWrite = new_row;
+
+  if (decoder->interlacebuf) {
+    uint32_t width = uint32_t(decoder->mFrameRect.width);
+
+    // We'll output the deinterlaced version of the row.
+    rowToWrite = decoder->interlacebuf + (row_num * decoder->mChannels * width);
+
+    // Update the deinterlaced version of this row with the new data.
+    png_progressive_combine_row(png_ptr, rowToWrite, new_row);
+  }
+
+  decoder->WriteRow(rowToWrite);
+}
+
+void
+nsPNGDecoder::WriteRow(uint8_t* aRow)
+{
+  MOZ_ASSERT(aRow);
+
+  uint8_t* rowToWrite = aRow;
+  uint32_t width = uint32_t(mFrameRect.width);
+
+  // Apply color management to the row, if necessary, before writing it out.
+  if (mTransform) {
+    if (mCMSLine) {
+      qcms_transform_data(mTransform, rowToWrite, mCMSLine, width);
+
+      // Copy alpha over.
+      if (mChannels == 2 || mChannels == 4) {
+        for (uint32_t i = 0; i < width; ++i) {
+          mCMSLine[4 * i + 3] = rowToWrite[mChannels * i + mChannels - 1];
+        }
+      }
+
+      rowToWrite = mCMSLine;
+    } else {
+      qcms_transform_data(mTransform, rowToWrite, rowToWrite, width);
+    }
+  }
+
+  // Write this row to the SurfacePipe.
+  DebugOnly<WriteState> result = WriteState::FAILURE;
+  switch (format) {
+    case SurfaceFormat::B8G8R8X8:
+      result = mPipe.WritePixelsToRow<uint32_t>([&]{
+        return PackRGBPixelAndAdvance(rowToWrite);
+      });
+      break;
+
+    case SurfaceFormat::B8G8R8A8:
+      if (mDisablePremultipliedAlpha) {
+        result = mPipe.WritePixelsToRow<uint32_t>([&]{
+          return PackUnpremultipliedRGBAPixelAndAdvance(rowToWrite);
+        });
+      } else {
+        result = mPipe.WritePixelsToRow<uint32_t>([&]{
+          return PackRGBAPixelAndAdvance(rowToWrite);
+        });
+      }
+      break;
+
+    default:
+      png_error(mPNG, "Invalid SurfaceFormat");
+  }
+
+  MOZ_ASSERT(WriteState(result) != WriteState::FAILURE);
+
+  PostInvalidationIfNeeded();
+}
+
+void
+nsPNGDecoder::DoTerminate(png_structp aPNGStruct, TerminalState aState)
+{
+  // Stop processing data. Note that we intentionally ignore the return value of
+  // png_process_data_pause(), which tells us how many bytes of the data that
+  // was passed to png_process_data() have not been consumed yet, because now
+  // that we've reached a terminal state, we won't do any more decoding or call
+  // back into libpng anymore.
+  png_process_data_pause(aPNGStruct, /* save = */ false);
+
+  mNextTransition = aState == TerminalState::SUCCESS
+                  ? Transition::TerminateSuccess()
+                  : Transition::TerminateFailure();
+}
+
+void
+nsPNGDecoder::DoYield(png_structp aPNGStruct)
+{
+  // Pause data processing. png_process_data_pause() returns how many bytes of
+  // the data that was passed to png_process_data() have not been consumed yet.
+  // We use this information to tell StreamingLexer where to place us in the
+  // input stream when we come back from the yield.
+  png_size_t pendingBytes = png_process_data_pause(aPNGStruct,
+                                                   /* save = */ false);
+
+  MOZ_ASSERT(pendingBytes < mLastChunkLength);
+  size_t consumedBytes = mLastChunkLength - min(pendingBytes, mLastChunkLength);
+
+  mNextTransition =
+    Transition::ContinueUnbufferedAfterYield(State::PNG_DATA, consumedBytes);
+}
+
+#ifdef PNG_APNG_SUPPORTED
+// got the header of a new frame that's coming
+void
+nsPNGDecoder::frame_info_callback(png_structp png_ptr, png_uint_32 frame_num)
+{
+  nsPNGDecoder* decoder =
+               static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
+
+  // old frame is done
+  decoder->EndImageFrame();
+
+  const bool previousFrameWasHidden = decoder->mFrameIsHidden;
+
+  if (!previousFrameWasHidden && decoder->IsFirstFrameDecode()) {
+    // We're about to get a second non-hidden frame, but we only want the first.
+    // Stop decoding now. (And avoid allocating the unnecessary buffers below.)
+    decoder->PostDecodeDone();
+    return decoder->DoTerminate(png_ptr, TerminalState::SUCCESS);
+  }
+
+  // Only the first frame can be hidden, so unhide unconditionally here.
+  decoder->mFrameIsHidden = false;
+
+  // Save the information necessary to create the frame; we'll actually create
+  // it when we return from the yield.
+  const IntRect frameRect(png_get_next_frame_x_offset(png_ptr, decoder->mInfo),
+                          png_get_next_frame_y_offset(png_ptr, decoder->mInfo),
+                          png_get_next_frame_width(png_ptr, decoder->mInfo),
+                          png_get_next_frame_height(png_ptr, decoder->mInfo));
+  const bool isInterlaced = bool(decoder->interlacebuf);
+
+#ifndef MOZ_EMBEDDED_LIBPNG
+  // if using system library, check frame_width and height against 0
+  if (frameRect.width == 0) {
+    png_error(png_ptr, "Frame width must not be 0");
+  }
+  if (frameRect.height == 0) {
+    png_error(png_ptr, "Frame height must not be 0");
+  }
+#endif
+
+  const FrameInfo info { decoder->format, frameRect, isInterlaced };
+
+  // If the previous frame was hidden, skip the yield (which will mislead the
+  // caller, who will think the previous frame was real) and just allocate the
+  // new frame here.
+  if (previousFrameWasHidden) {
+    if (NS_FAILED(decoder->CreateFrame(info))) {
+      return decoder->DoTerminate(png_ptr, TerminalState::FAILURE);
+    }
+
+    MOZ_ASSERT(decoder->mImageData, "Should have a buffer now");
+    return;  // No yield, so we'll just keep decoding.
+  }
+
+  // Yield to the caller to notify them that the previous frame is now complete.
+  decoder->mNextFrameInfo = Some(info);
+  return decoder->DoYield(png_ptr);
+}
+#endif
+
+void
+nsPNGDecoder::end_callback(png_structp png_ptr, png_infop info_ptr)
+{
+  /* libpng comments:
+   *
+   * this function is called when the whole image has been read,
+   * including any chunks after the image (up to and including
+   * the IEND).  You will usually have the same info chunk as you
+   * had in the header, although some data may have been added
+   * to the comments and time fields.
+   *
+   * Most people won't do much here, perhaps setting a flag that
+   * marks the image as finished.
+   */
+
+  nsPNGDecoder* decoder =
+               static_cast<nsPNGDecoder*>(png_get_progressive_ptr(png_ptr));
+
+  // We shouldn't get here if we've hit an error
+  MOZ_ASSERT(!decoder->HasError(), "Finishing up PNG but hit error!");
+
+  int32_t loop_count = 0;
+#ifdef PNG_APNG_SUPPORTED
+  if (png_get_valid(png_ptr, info_ptr, PNG_INFO_acTL)) {
+    int32_t num_plays = png_get_num_plays(png_ptr, info_ptr);
+    loop_count = num_plays - 1;
+  }
+#endif
+
+  // Send final notifications.
+  decoder->EndImageFrame();
+  decoder->PostDecodeDone(loop_count);
+  return decoder->DoTerminate(png_ptr, TerminalState::SUCCESS);
+}
+
+
+void
+nsPNGDecoder::error_callback(png_structp png_ptr, png_const_charp error_msg)
+{
+  MOZ_LOG(sPNGLog, LogLevel::Error, ("libpng error: %s\n", error_msg));
+  png_longjmp(png_ptr, 1);
+}
+
+
+void
+nsPNGDecoder::warning_callback(png_structp png_ptr, png_const_charp warning_msg)
+{
+  MOZ_LOG(sPNGLog, LogLevel::Warning, ("libpng warning: %s\n", warning_msg));
+}
+
+Maybe<Telemetry::ID>
+nsPNGDecoder::SpeedHistogram() const
+{
+  return Some(Telemetry::IMAGE_DECODE_SPEED_PNG);
+}
+
+bool
+nsPNGDecoder::IsValidICO() const
+{
+  // Only 32-bit RGBA PNGs are valid ICO resources; see here:
+  //   http://blogs.msdn.com/b/oldnewthing/archive/2010/10/22/10079192.aspx
+
+  // If there are errors in the call to png_get_IHDR, the error_callback in
+  // nsPNGDecoder.cpp is called.  In this error callback we do a longjmp, so
+  // we need to save the jump buffer here. Otherwise we'll end up without a
+  // proper callstack.
+  if (setjmp(png_jmpbuf(mPNG))) {
+    // We got here from a longjmp call indirectly from png_get_IHDR
+    return false;
+  }
+
+  png_uint_32
+      png_width,  // Unused
+      png_height; // Unused
+
+  int png_bit_depth,
+      png_color_type;
+
+  if (png_get_IHDR(mPNG, mInfo, &png_width, &png_height, &png_bit_depth,
+                   &png_color_type, nullptr, nullptr, nullptr)) {
+
+    return ((png_color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
+             png_color_type == PNG_COLOR_TYPE_RGB) &&
+            png_bit_depth == 8);
+  } else {
+    return false;
+  }
+}
+
+} // namespace image
+} // namespace mozilla