forked from mirrors/gecko-dev
		
	
		
			
				
	
	
		
			1035 lines
		
	
	
	
		
			36 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			1035 lines
		
	
	
	
		
			36 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /* -*- 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 "nsMemory.h"
 | |
| #include "nsRect.h"
 | |
| #include "nspr.h"
 | |
| #include "png.h"
 | |
| 
 | |
| #include "RasterImage.h"
 | |
| #include "SurfaceCache.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
 | |
| 
 | |
| /* Controls the maximum chunk size configuration for libpng. We set this to a
 | |
|  * very large number, 256MB specifically. */
 | |
| static constexpr png_alloc_size_t kPngMaxChunkSize = 0x10000000;
 | |
| 
 | |
| 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),
 | |
|       mFormat(SurfaceFormat::UNKNOWN),
 | |
|       mChannels(0),
 | |
|       mPass(0),
 | |
|       mFrameIsHidden(false),
 | |
|       mDisablePremultipliedAlpha(false),
 | |
|       mGotInfoCallback(false),
 | |
|       mUsePipeTransform(false),
 | |
|       mNumFrames(0) {}
 | |
| 
 | |
| nsPNGDecoder::~nsPNGDecoder() {
 | |
|   if (mPNG) {
 | |
|     png_destroy_read_struct(&mPNG, mInfo ? &mInfo : nullptr, nullptr);
 | |
|   }
 | |
|   if (mCMSLine) {
 | |
|     free(mCMSLine);
 | |
|   }
 | |
|   if (interlacebuf) {
 | |
|     free(interlacebuf);
 | |
|   }
 | |
| }
 | |
| 
 | |
| nsPNGDecoder::TransparencyType nsPNGDecoder::GetTransparencyType(
 | |
|     const IntRect& aFrameRect) {
 | |
|   // Check if the image has a transparent color in its palette.
 | |
|   if (HasAlphaChannel()) {
 | |
|     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.mFrameRect);
 | |
|   PostHasTransparencyIfNeeded(transparency);
 | |
|   mFormat = transparency == TransparencyType::eNone ? SurfaceFormat::OS_RGBX
 | |
|                                                     : SurfaceFormat::OS_RGBA;
 | |
| 
 | |
|   // 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);
 | |
| 
 | |
|   Maybe<AnimationParams> animParams;
 | |
| #ifdef PNG_APNG_SUPPORTED
 | |
|   if (!IsFirstFrameDecode() && 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();
 | |
|     }
 | |
| 
 | |
|     animParams.emplace(
 | |
|         AnimationParams{aFrameInfo.mFrameRect,
 | |
|                         FrameTimeout::FromRawMilliseconds(mAnimInfo.mTimeout),
 | |
|                         mNumFrames, mAnimInfo.mBlend, mAnimInfo.mDispose});
 | |
|   }
 | |
| #endif
 | |
| 
 | |
|   // 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;
 | |
|   }
 | |
| 
 | |
|   SurfaceFormat inFormat;
 | |
|   if (mTransform && !mUsePipeTransform) {
 | |
|     // QCMS will output in the correct format.
 | |
|     inFormat = mFormat;
 | |
|   } else if (transparency == TransparencyType::eAlpha) {
 | |
|     // We are outputting directly as RGBA, so we need to swap at this step.
 | |
|     inFormat = SurfaceFormat::R8G8B8A8;
 | |
|   } else {
 | |
|     // We have no alpha channel, so we need to unpack from RGB to BGRA.
 | |
|     inFormat = SurfaceFormat::R8G8B8;
 | |
|   }
 | |
| 
 | |
|   // Only apply premultiplication if the frame has true alpha. If we ever
 | |
|   // support downscaling animated images, we will need to premultiply for frame
 | |
|   // rect transparency when downscaling as well.
 | |
|   if (transparency == TransparencyType::eAlpha && !mDisablePremultipliedAlpha) {
 | |
|     pipeFlags |= SurfacePipeFlags::PREMULTIPLY_ALPHA;
 | |
|   }
 | |
| 
 | |
|   qcms_transform* pipeTransform = mUsePipeTransform ? mTransform : nullptr;
 | |
|   Maybe<SurfacePipe> pipe = SurfacePipeFactory::CreateSurfacePipe(
 | |
|       this, Size(), OutputSize(), aFrameInfo.mFrameRect, inFormat, mFormat,
 | |
|       animParams, pipeTransform, pipeFlags);
 | |
| 
 | |
|   if (!pipe) {
 | |
|     mPipe = SurfacePipe();
 | |
|     return NS_ERROR_FAILURE;
 | |
|   }
 | |
| 
 | |
|   mPipe = std::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));
 | |
| 
 | |
|   return NS_OK;
 | |
| }
 | |
| 
 | |
| // set timeout and frame disposal method for the current frame
 | |
| void nsPNGDecoder::EndImageFrame() {
 | |
|   if (mFrameIsHidden) {
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   mNumFrames++;
 | |
| 
 | |
|   Opacity opacity = mFormat == SurfaceFormat::OS_RGBX
 | |
|                         ? Opacity::FULLY_OPAQUE
 | |
|                         : Opacity::SOME_TRANSPARENCY;
 | |
| 
 | |
|   PostFrameStop(opacity);
 | |
| }
 | |
| 
 | |
| nsresult nsPNGDecoder::InitInternal() {
 | |
|   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
 | |
|                                      101, 88, 73, 102, '\0',   // eXIf
 | |
|                                      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 == CMSMode::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);
 | |
|   png_set_chunk_malloc_max(mPNG, kPngMaxChunkSize);
 | |
| #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
 | |
| uint32_t nsPNGDecoder::ReadColorProfile(png_structp png_ptr, png_infop info_ptr,
 | |
|                                         int color_type, bool* sRGBTag) {
 | |
|   // 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);
 | |
| 
 | |
|     mInProfile = qcms_profile_from_memory((char*)profileData, profileLen);
 | |
|     if (mInProfile) {
 | |
|       uint32_t profileSpace = qcms_profile_get_color_space(mInProfile);
 | |
| 
 | |
|       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(mInProfile);
 | |
|         mInProfile = nullptr;
 | |
|       } else {
 | |
|         return qcms_profile_get_rendering_intent(mInProfile);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   // Check sRGB chunk
 | |
|   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sRGB)) {
 | |
|     *sRGBTag = true;
 | |
| 
 | |
|     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};
 | |
|     return map[fileIntent];
 | |
|   }
 | |
| 
 | |
|   // Check gAMA/cHRM chunks
 | |
|   if (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);
 | |
| 
 | |
|     mInProfile = qcms_profile_create_rgb_with_gamma(whitePoint, primaries,
 | |
|                                                     1.0 / gammaOfFile);
 | |
| 
 | |
|     if (mInProfile) {
 | |
|       png_set_gray_to_rgb(png_ptr);
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   return QCMS_INTENT_PERCEPTUAL;  // Our default
 | |
| }
 | |
| 
 | |
| 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));
 | |
| 
 | |
|   if (decoder->mGotInfoCallback) {
 | |
|     MOZ_LOG(sPNGLog, LogLevel::Warning,
 | |
|             ("libpng called info_callback more than once\n"));
 | |
|     return;
 | |
|   }
 | |
| 
 | |
|   decoder->mGotInfoCallback = true;
 | |
| 
 | |
|   // 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 (width > SurfaceCache::MaximumCapacity() / (bit_depth > 8 ? 16 : 8)) {
 | |
|     // libpng needs space to allocate two row buffers
 | |
|     png_error(decoder->mPNG, "Image is too wide");
 | |
|   }
 | |
| 
 | |
|   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);
 | |
|   }
 | |
| 
 | |
|   // We only need to extract the color profile for non-metadata decodes. It is
 | |
|   // fairly expensive to read the profile and create the transform so we should
 | |
|   // avoid it if not necessary.
 | |
|   uint32_t intent = -1;
 | |
|   bool sRGBTag = false;
 | |
|   if (!decoder->IsMetadataDecode()) {
 | |
|     if (decoder->mCMSMode != CMSMode::Off) {
 | |
|       intent = gfxPlatform::GetRenderingIntent();
 | |
|       uint32_t pIntent =
 | |
|           decoder->ReadColorProfile(png_ptr, info_ptr, color_type, &sRGBTag);
 | |
|       // If we're not mandating an intent, use the one from the image.
 | |
|       if (intent == uint32_t(-1)) {
 | |
|         intent = pIntent;
 | |
|       }
 | |
|     }
 | |
|     if (!decoder->mInProfile || !decoder->GetCMSOutputProfile()) {
 | |
|       png_set_gray_to_rgb(png_ptr);
 | |
| 
 | |
|       // only do gamma correction if CMS isn't entirely disabled
 | |
|       if (decoder->mCMSMode != CMSMode::Off) {
 | |
|         PNGDoGammaCorrection(png_ptr, info_ptr);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   // 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 > 4) {
 | |
|     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
 | |
| 
 | |
|   auto transparency = decoder->GetTransparencyType(frameRect);
 | |
|   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.
 | |
|     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);
 | |
|   }
 | |
| 
 | |
|   if (decoder->mInProfile && decoder->GetCMSOutputProfile()) {
 | |
|     qcms_data_type inType;
 | |
|     qcms_data_type outType;
 | |
| 
 | |
|     uint32_t profileSpace = qcms_profile_get_color_space(decoder->mInProfile);
 | |
|     decoder->mUsePipeTransform = profileSpace != icSigGrayData;
 | |
|     if (decoder->mUsePipeTransform) {
 | |
|       // If the transform happens with SurfacePipe, it will be in RGBA if we
 | |
|       // have an alpha channel, because the swizzle and premultiplication
 | |
|       // happens after color management. Otherwise it will be in BGRA because
 | |
|       // the swizzle happens at the start.
 | |
|       if (transparency == TransparencyType::eAlpha) {
 | |
|         inType = QCMS_DATA_RGBA_8;
 | |
|         outType = QCMS_DATA_RGBA_8;
 | |
|       } else {
 | |
|         inType = gfxPlatform::GetCMSOSRGBAType();
 | |
|         outType = inType;
 | |
|       }
 | |
|     } else {
 | |
|       if (color_type & PNG_COLOR_MASK_ALPHA) {
 | |
|         inType = QCMS_DATA_GRAYA_8;
 | |
|         outType = gfxPlatform::GetCMSOSRGBAType();
 | |
|       } else {
 | |
|         inType = QCMS_DATA_GRAY_8;
 | |
|         outType = gfxPlatform::GetCMSOSRGBAType();
 | |
|       }
 | |
|     }
 | |
| 
 | |
|     decoder->mTransform = qcms_transform_create(decoder->mInProfile, inType,
 | |
|                                                 decoder->GetCMSOutputProfile(),
 | |
|                                                 outType, (qcms_intent)intent);
 | |
|   } else if ((sRGBTag && decoder->mCMSMode == CMSMode::TaggedOnly) ||
 | |
|              decoder->mCMSMode == CMSMode::All) {
 | |
|     // If the transform happens with SurfacePipe, it will be in RGBA if we
 | |
|     // have an alpha channel, because the swizzle and premultiplication
 | |
|     // happens after color management. Otherwise it will be in OS_RGBA because
 | |
|     // the swizzle happens at the start.
 | |
|     if (transparency == TransparencyType::eAlpha) {
 | |
|       decoder->mTransform =
 | |
|           decoder->GetCMSsRGBTransform(SurfaceFormat::R8G8B8A8);
 | |
|     } else {
 | |
|       decoder->mTransform =
 | |
|           decoder->GetCMSsRGBTransform(SurfaceFormat::OS_RGBA);
 | |
|     }
 | |
|     decoder->mUsePipeTransform = true;
 | |
|   }
 | |
| 
 | |
| #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{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 && !decoder->mUsePipeTransform) {
 | |
|     decoder->mCMSLine =
 | |
|         static_cast<uint8_t*>(malloc(sizeof(uint32_t) * 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();
 | |
| 
 | |
|       if (bufferSize > SurfaceCache::MaximumCapacity()) {
 | |
|         png_error(decoder->mPNG, "Insufficient memory to deinterlace image");
 | |
|       }
 | |
| 
 | |
|       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));
 | |
| }
 | |
| 
 | |
| 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);
 | |
| 
 | |
|   if (decoder->interlacebuf) {
 | |
|     uint32_t width = uint32_t(decoder->mFrameRect.Width());
 | |
| 
 | |
|     // We'll output the deinterlaced version of the row.
 | |
|     uint8_t* 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);
 | |
|   } else {
 | |
|     decoder->WriteRow(new_row);
 | |
|   }
 | |
| }
 | |
| 
 | |
| 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.
 | |
|   // This is only needed for grayscale images.
 | |
|   if (mTransform && !mUsePipeTransform) {
 | |
|     MOZ_ASSERT(mCMSLine);
 | |
|     qcms_transform_data(mTransform, rowToWrite, mCMSLine, width);
 | |
|     rowToWrite = mCMSLine;
 | |
|   }
 | |
| 
 | |
|   // Write this row to the SurfacePipe.
 | |
|   DebugOnly<WriteState> result =
 | |
|       mPipe.WriteBuffer(reinterpret_cast<uint32_t*>(rowToWrite));
 | |
|   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);
 | |
| }
 | |
| 
 | |
| nsresult nsPNGDecoder::FinishInternal() {
 | |
|   // We shouldn't be called in error cases.
 | |
|   MOZ_ASSERT(!HasError(), "Can't call FinishInternal on error!");
 | |
| 
 | |
|   if (IsMetadataDecode()) {
 | |
|     return NS_OK;
 | |
|   }
 | |
| 
 | |
|   int32_t loop_count = 0;
 | |
| #ifdef PNG_APNG_SUPPORTED
 | |
|   if (png_get_valid(mPNG, mInfo, PNG_INFO_acTL)) {
 | |
|     int32_t num_plays = png_get_num_plays(mPNG, mInfo);
 | |
|     loop_count = num_plays - 1;
 | |
|   }
 | |
| #endif
 | |
| 
 | |
|   if (InFrame()) {
 | |
|     EndImageFrame();
 | |
|   }
 | |
|   PostDecodeDone(loop_count);
 | |
| 
 | |
|   return NS_OK;
 | |
| }
 | |
| 
 | |
| #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.)
 | |
|     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{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!");
 | |
| 
 | |
|   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::HistogramID> nsPNGDecoder::SpeedHistogram() const {
 | |
|   return Some(Telemetry::IMAGE_DECODE_SPEED_PNG);
 | |
| }
 | |
| 
 | |
| bool nsPNGDecoder::IsValidICOResource() 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
 | 
