image/RasterImage.cpp
author Henri Sivonen <hsivonen@hsivonen.fi>
Fri, 06 Jul 2018 10:44:43 +0300
changeset 489140 4ef0f163fdeb9afeddd87b37bfd987298c038542
parent 488037 58968b3702fd25b217a4eddf6d3348df8c1fcbc0
child 489182 69a4c2a0aac6e8bfc041a82b634611e1432af36b
permissions -rw-r--r--
Bug 1402247 - Use encoding_rs for XPCOM string encoding conversions. r=Nika,erahm,froydnj. Correctness improvements: * UTF errors are handled safely per spec instead of dangerously truncating strings. * There are fewer converter implementations. Performance improvements: * The old code did exact buffer length math, which meant doing UTF math twice on each input string (once for length calculation and another time for conversion). Exact length math is more complicated when handling errors properly, which the old code didn't do. The new code does UTF math on the string content only once (when converting) but risks allocating more than once. There are heuristics in place to lower the probability of reallocation in cases where the double math avoidance isn't enough of a saving to absorb an allocation and memcpy. * Previously, in UTF-16 <-> UTF-8 conversions, an ASCII prefix was optimized but a single non-ASCII code point pessimized the rest of the string. The new code tries to get back on the fast ASCII path. * UTF-16 to Latin1 conversion guarantees less about handling of out-of-range input to eliminate an operation from the inner loop on x86/x86_64. * When assigning to a pre-existing string, the new code tries to reuse the old buffer instead of first releasing the old buffer and then allocating a new one. * When reallocating from the new code, the memcpy covers only the data that is part of the logical length of the old string instead of memcpying the whole capacity. (For old callers old excess memcpy behavior is preserved due to bogus callers. See bug 1472113.) * UTF-8 strings in XPConnect that are in the Latin1 range are passed to SpiderMonkey as Latin1. New features: * Conversion between UTF-8 and Latin1 is added in order to enable faster future interop between Rust code (or otherwise UTF-8-using code) and text node and SpiderMonkey code that uses Latin1. MozReview-Commit-ID: JaJuExfILM9

/* -*- 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/. */

// Must #include ImageLogging.h before any IPDL-generated files or other files
// that #include prlog.h
#include "ImageLogging.h"

#include "RasterImage.h"

#include "gfxPlatform.h"
#include "nsComponentManagerUtils.h"
#include "nsError.h"
#include "DecodePool.h"
#include "Decoder.h"
#include "prenv.h"
#include "prsystem.h"
#include "IDecodingTask.h"
#include "ImageRegion.h"
#include "Layers.h"
#include "LookupResult.h"
#include "nsIConsoleService.h"
#include "nsIInputStream.h"
#include "nsIScriptError.h"
#include "nsISupportsPrimitives.h"
#include "nsMemory.h"
#include "nsPresContext.h"
#include "SourceBuffer.h"
#include "SurfaceCache.h"
#include "FrameAnimator.h"

#include "gfxContext.h"

#include "mozilla/gfx/2D.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/Likely.h"
#include "mozilla/RefPtr.h"
#include "mozilla/Move.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Services.h"
#include "mozilla/SizeOfState.h"
#include <stdint.h>
#include "mozilla/Telemetry.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/Tuple.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/gfx/Scale.h"

#include "GeckoProfiler.h"
#include "gfx2DGlue.h"
#include "gfxPrefs.h"
#include <algorithm>

namespace mozilla {

using namespace gfx;
using namespace layers;

namespace image {

using std::ceil;
using std::min;

#ifndef DEBUG
NS_IMPL_ISUPPORTS(RasterImage, imgIContainer, nsIProperties)
#else
NS_IMPL_ISUPPORTS(RasterImage, imgIContainer, nsIProperties,
                  imgIContainerDebug)
#endif

//******************************************************************************
RasterImage::RasterImage(nsIURI* aURI /* = nullptr */) :
  ImageResource(aURI), // invoke superclass's constructor
  mSize(0,0),
  mLockCount(0),
  mDecoderType(DecoderType::UNKNOWN),
  mDecodeCount(0),
#ifdef DEBUG
  mFramesNotified(0),
#endif
  mSourceBuffer(MakeNotNull<SourceBuffer*>()),
  mHasSize(false),
  mTransient(false),
  mSyncLoad(false),
  mDiscardable(false),
  mSomeSourceData(false),
  mAllSourceData(false),
  mHasBeenDecoded(false),
  mPendingAnimation(false),
  mAnimationFinished(false),
  mWantFullDecode(false)
{
}

//******************************************************************************
RasterImage::~RasterImage()
{
  // Make sure our SourceBuffer is marked as complete. This will ensure that any
  // outstanding decoders terminate.
  if (!mSourceBuffer->IsComplete()) {
    mSourceBuffer->Complete(NS_ERROR_ABORT);
  }

  // Release all frames from the surface cache.
  SurfaceCache::RemoveImage(ImageKey(this));

  // Record Telemetry.
  Telemetry::Accumulate(Telemetry::IMAGE_DECODE_COUNT, mDecodeCount);
}

nsresult
RasterImage::Init(const char* aMimeType,
                  uint32_t aFlags)
{
  // We don't support re-initialization
  if (mInitialized) {
    return NS_ERROR_ILLEGAL_VALUE;
  }

  // Not sure an error can happen before init, but be safe
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  // We want to avoid redecodes for transient images.
  MOZ_ASSERT_IF(aFlags & INIT_FLAG_TRANSIENT,
                !(aFlags & INIT_FLAG_DISCARDABLE));

  // Store initialization data
  mDiscardable = !!(aFlags & INIT_FLAG_DISCARDABLE);
  mWantFullDecode = !!(aFlags & INIT_FLAG_DECODE_IMMEDIATELY);
  mTransient = !!(aFlags & INIT_FLAG_TRANSIENT);
  mSyncLoad = !!(aFlags & INIT_FLAG_SYNC_LOAD);

  // Use the MIME type to select a decoder type, and make sure there *is* a
  // decoder for this MIME type.
  NS_ENSURE_ARG_POINTER(aMimeType);
  mDecoderType = DecoderFactory::GetDecoderType(aMimeType);
  if (mDecoderType == DecoderType::UNKNOWN) {
    return NS_ERROR_FAILURE;
  }

  // Lock this image's surfaces in the SurfaceCache if we're not discardable.
  if (!mDiscardable) {
    mLockCount++;
    SurfaceCache::LockImage(ImageKey(this));
  }

  // Mark us as initialized
  mInitialized = true;

  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP_(void)
RasterImage::RequestRefresh(const TimeStamp& aTime)
{
  if (HadRecentRefresh(aTime)) {
    return;
  }

  EvaluateAnimation();

  if (!mAnimating) {
    return;
  }

  RefreshResult res;
  if (mAnimationState) {
    MOZ_ASSERT(mFrameAnimator);
    res = mFrameAnimator->RequestRefresh(*mAnimationState, aTime, mAnimationFinished);
  }

  if (res.mFrameAdvanced) {
    // Notify listeners that our frame has actually changed, but do this only
    // once for all frames that we've now passed (if AdvanceFrame() was called
    // more than once).
    #ifdef DEBUG
      mFramesNotified++;
    #endif

    NotifyProgress(NoProgress, res.mDirtyRect);
  }

  if (res.mAnimationFinished) {
    mAnimationFinished = true;
    EvaluateAnimation();
  }
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::GetWidth(int32_t* aWidth)
{
  NS_ENSURE_ARG_POINTER(aWidth);

  if (mError) {
    *aWidth = 0;
    return NS_ERROR_FAILURE;
  }

  *aWidth = mSize.width;
  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::GetHeight(int32_t* aHeight)
{
  NS_ENSURE_ARG_POINTER(aHeight);

  if (mError) {
    *aHeight = 0;
    return NS_ERROR_FAILURE;
  }

  *aHeight = mSize.height;
  return NS_OK;
}

//******************************************************************************
nsresult
RasterImage::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  if (mNativeSizes.IsEmpty()) {
    aNativeSizes.Clear();
    aNativeSizes.AppendElement(mSize);
  } else {
    aNativeSizes = mNativeSizes;
  }

  return NS_OK;
}

//******************************************************************************
size_t
RasterImage::GetNativeSizesLength() const
{
  if (mError || !mHasSize) {
    return 0;
  }

  if (mNativeSizes.IsEmpty()) {
    return 1;
  }

  return mNativeSizes.Length();
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::GetIntrinsicSize(nsSize* aSize)
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  *aSize = nsSize(nsPresContext::CSSPixelsToAppUnits(mSize.width),
                  nsPresContext::CSSPixelsToAppUnits(mSize.height));
  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::GetIntrinsicRatio(nsSize* aRatio)
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  *aRatio = nsSize(mSize.width, mSize.height);
  return NS_OK;
}

NS_IMETHODIMP_(Orientation)
RasterImage::GetOrientation()
{
  return mOrientation;
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::GetType(uint16_t* aType)
{
  NS_ENSURE_ARG_POINTER(aType);

  *aType = imgIContainer::TYPE_RASTER;
  return NS_OK;
}

LookupResult
RasterImage::LookupFrameInternal(const IntSize& aSize,
                                 uint32_t aFlags,
                                 PlaybackType aPlaybackType)
{
  if (mAnimationState && aPlaybackType == PlaybackType::eAnimated) {
    MOZ_ASSERT(mFrameAnimator);
    MOZ_ASSERT(ToSurfaceFlags(aFlags) == DefaultSurfaceFlags(),
               "Can't composite frames with non-default surface flags");
    return mFrameAnimator->GetCompositedFrame(*mAnimationState);
  }

  SurfaceFlags surfaceFlags = ToSurfaceFlags(aFlags);

  // We don't want any substitution for sync decodes, and substitution would be
  // illegal when high quality downscaling is disabled, so we use
  // SurfaceCache::Lookup in this case.
  if ((aFlags & FLAG_SYNC_DECODE) || !(aFlags & FLAG_HIGH_QUALITY_SCALING)) {
    return SurfaceCache::Lookup(ImageKey(this),
                                RasterSurfaceKey(aSize,
                                                 surfaceFlags,
                                                 PlaybackType::eStatic));
  }

  // We'll return the best match we can find to the requested frame.
  return SurfaceCache::LookupBestMatch(ImageKey(this),
                                       RasterSurfaceKey(aSize,
                                                        surfaceFlags,
                                                        PlaybackType::eStatic));
}

LookupResult
RasterImage::LookupFrame(const IntSize& aSize,
                         uint32_t aFlags,
                         PlaybackType aPlaybackType)
{
  MOZ_ASSERT(NS_IsMainThread());

  // If we're opaque, we don't need to care about premultiplied alpha, because
  // that can only matter for frames with transparency.
  if (IsOpaque()) {
    aFlags &= ~FLAG_DECODE_NO_PREMULTIPLY_ALPHA;
  }

  IntSize requestedSize = CanDownscaleDuringDecode(aSize, aFlags)
                        ? aSize : mSize;
  if (requestedSize.IsEmpty()) {
    // Can't decode to a surface of zero size.
    return LookupResult(MatchType::NOT_FOUND);
  }

  LookupResult result =
    LookupFrameInternal(requestedSize, aFlags, aPlaybackType);

  if (!result && !mHasSize) {
    // We can't request a decode without knowing our intrinsic size. Give up.
    return LookupResult(MatchType::NOT_FOUND);
  }

  if (result.Type() == MatchType::NOT_FOUND ||
      result.Type() == MatchType::SUBSTITUTE_BECAUSE_NOT_FOUND ||
      ((aFlags & FLAG_SYNC_DECODE) && !result)) {
    // We don't have a copy of this frame, and there's no decoder working on
    // one. (Or we're sync decoding and the existing decoder hasn't even started
    // yet.) Trigger decoding so it'll be available next time.
    MOZ_ASSERT(aPlaybackType != PlaybackType::eAnimated ||
               gfxPrefs::ImageMemAnimatedDiscardable() ||
               !mAnimationState || mAnimationState->KnownFrameCount() < 1,
               "Animated frames should be locked");

    // The surface cache may suggest the preferred size we are supposed to
    // decode at. This should only happen if we accept substitutions.
    if (!result.SuggestedSize().IsEmpty()) {
      MOZ_ASSERT(!(aFlags & FLAG_SYNC_DECODE) &&
                  (aFlags & FLAG_HIGH_QUALITY_SCALING));
      requestedSize = result.SuggestedSize();
    }

    bool ranSync = Decode(requestedSize, aFlags, aPlaybackType);

    // If we can or did sync decode, we should already have the frame.
    if (ranSync || (aFlags & FLAG_SYNC_DECODE)) {
      result = LookupFrameInternal(requestedSize, aFlags, aPlaybackType);
    }
  }

  if (!result) {
    // We still weren't able to get a frame. Give up.
    return result;
  }

  if (result.Surface()->GetCompositingFailed()) {
    DrawableSurface tmp = std::move(result.Surface());
    return result;
  }

  MOZ_ASSERT(!result.Surface()->GetIsPaletted(),
             "Should not have a paletted frame");

  // Sync decoding guarantees that we got the frame, but if it's owned by an
  // async decoder that's currently running, the contents of the frame may not
  // be available yet. Make sure we get everything.
  if (mAllSourceData && (aFlags & FLAG_SYNC_DECODE)) {
    result.Surface()->WaitUntilFinished();
  }

  // If we could have done some decoding in this function we need to check if
  // that decoding encountered an error and hence aborted the surface. We want
  // to avoid calling IsAborted if we weren't passed any sync decode flag because
  // IsAborted acquires the monitor for the imgFrame.
  if (aFlags & (FLAG_SYNC_DECODE | FLAG_SYNC_DECODE_IF_FAST) &&
    result.Surface()->IsAborted()) {
    DrawableSurface tmp = std::move(result.Surface());
    return result;
  }

  return result;
}

bool
RasterImage::IsOpaque()
{
  if (mError) {
    return false;
  }

  Progress progress = mProgressTracker->GetProgress();

  // If we haven't yet finished decoding, the safe answer is "not opaque".
  if (!(progress & FLAG_DECODE_COMPLETE)) {
    return false;
  }

  // Other, we're opaque if FLAG_HAS_TRANSPARENCY is not set.
  return !(progress & FLAG_HAS_TRANSPARENCY);
}

NS_IMETHODIMP_(bool)
RasterImage::WillDrawOpaqueNow()
{
  if (!IsOpaque()) {
    return false;
  }

  if (mAnimationState) {
    if (!gfxPrefs::ImageMemAnimatedDiscardable()) {
      // We never discard frames of animated images.
      return true;
    } else {
      if (mAnimationState->GetCompositedFrameInvalid()) {
        // We're not going to draw anything at all.
        return false;
      }
    }
  }

  // If we are not locked our decoded data could get discard at any time (ie
  // between the call to this function and when we are asked to draw), so we
  // have to return false if we are unlocked.
  if (mLockCount == 0) {
    return false;
  }

  LookupResult result =
    SurfaceCache::LookupBestMatch(ImageKey(this),
                                  RasterSurfaceKey(mSize,
                                                   DefaultSurfaceFlags(),
                                                   PlaybackType::eStatic));
  MatchType matchType = result.Type();
  if (matchType == MatchType::NOT_FOUND || matchType == MatchType::PENDING ||
      !result.Surface()->IsFinished()) {
    return false;
  }

  return true;
}

void
RasterImage::OnSurfaceDiscarded(const SurfaceKey& aSurfaceKey)
{
  MOZ_ASSERT(mProgressTracker);

  bool animatedFramesDiscarded =
    mAnimationState && aSurfaceKey.Playback() == PlaybackType::eAnimated;

  nsCOMPtr<nsIEventTarget> eventTarget;
  if (mProgressTracker) {
    eventTarget = mProgressTracker->GetEventTarget();
  } else {
    eventTarget = do_GetMainThread();
  }

  RefPtr<RasterImage> image = this;
  nsCOMPtr<nsIRunnable> ev = NS_NewRunnableFunction(
                            "RasterImage::OnSurfaceDiscarded",
                            [=]() -> void {
    image->OnSurfaceDiscardedInternal(animatedFramesDiscarded);
  });
  eventTarget->Dispatch(ev.forget(), NS_DISPATCH_NORMAL);
}

void
RasterImage::OnSurfaceDiscardedInternal(bool aAnimatedFramesDiscarded)
{
  MOZ_ASSERT(NS_IsMainThread());

  if (aAnimatedFramesDiscarded && mAnimationState) {
    MOZ_ASSERT(gfxPrefs::ImageMemAnimatedDiscardable());
    ReleaseImageContainer();
    gfx::IntRect rect =
      mAnimationState->UpdateState(mAnimationFinished, this, mSize);
    NotifyProgress(NoProgress, rect);
  }

  if (mProgressTracker) {
    mProgressTracker->OnDiscard();
  }
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::GetAnimated(bool* aAnimated)
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  NS_ENSURE_ARG_POINTER(aAnimated);

  // If we have an AnimationState, we can know for sure.
  if (mAnimationState) {
    *aAnimated = true;
    return NS_OK;
  }

  // Otherwise, we need to have been decoded to know for sure, since if we were
  // decoded at least once mAnimationState would have been created for animated
  // images. This is true even though we check for animation during the
  // metadata decode, because we may still discover animation only during the
  // full decode for corrupt images.
  if (!mHasBeenDecoded) {
    return NS_ERROR_NOT_AVAILABLE;
  }

  // We know for sure
  *aAnimated = false;

  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP_(int32_t)
RasterImage::GetFirstFrameDelay()
{
  if (mError) {
    return -1;
  }

  bool animated = false;
  if (NS_FAILED(GetAnimated(&animated)) || !animated) {
    return -1;
  }

  MOZ_ASSERT(mAnimationState, "Animated images should have an AnimationState");
  return mAnimationState->FirstFrameTimeout().AsEncodedValueDeprecated();
}

NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
RasterImage::GetFrame(uint32_t aWhichFrame,
                      uint32_t aFlags)
{
  return GetFrameAtSize(mSize, aWhichFrame, aFlags);
}

NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
RasterImage::GetFrameAtSize(const IntSize& aSize,
                            uint32_t aWhichFrame,
                            uint32_t aFlags)
{
#ifdef DEBUG
  NotifyDrawingObservers();
#endif

  auto result = GetFrameInternal(aSize, Nothing(), aWhichFrame, aFlags);
  return mozilla::Get<2>(result).forget();
}

Tuple<ImgDrawResult, IntSize, RefPtr<SourceSurface>>
RasterImage::GetFrameInternal(const IntSize& aSize,
                              const Maybe<SVGImageContext>& aSVGContext,
                              uint32_t aWhichFrame,
                              uint32_t aFlags)
{
  MOZ_ASSERT(aWhichFrame <= FRAME_MAX_VALUE);

  if (aSize.IsEmpty() || aWhichFrame > FRAME_MAX_VALUE) {
    return MakeTuple(ImgDrawResult::BAD_ARGS, aSize,
                     RefPtr<SourceSurface>());
  }

  if (mError) {
    return MakeTuple(ImgDrawResult::BAD_IMAGE, aSize,
                     RefPtr<SourceSurface>());
  }

  // Get the frame. If it's not there, it's probably the caller's fault for
  // not waiting for the data to be loaded from the network or not passing
  // FLAG_SYNC_DECODE.
  LookupResult result =
    LookupFrame(aSize, aFlags, ToPlaybackType(aWhichFrame));

  // The surface cache may have suggested we use a different size than the
  // given size in the future. This may or may not be accompanied by an
  // actual surface, depending on what it has in its cache.
  IntSize suggestedSize = result.SuggestedSize().IsEmpty()
                          ? aSize : result.SuggestedSize();
  MOZ_ASSERT_IF(result.Type() == MatchType::SUBSTITUTE_BECAUSE_BEST,
                suggestedSize != aSize);

  if (!result) {
    // The OS threw this frame away and we couldn't redecode it.
    return MakeTuple(ImgDrawResult::TEMPORARY_ERROR, suggestedSize,
                     RefPtr<SourceSurface>());
  }

  RefPtr<SourceSurface> surface = result.Surface()->GetSourceSurface();
  if (!result.Surface()->IsFinished()) {
    return MakeTuple(ImgDrawResult::INCOMPLETE, suggestedSize, std::move(surface));
  }

  return MakeTuple(ImgDrawResult::SUCCESS, suggestedSize, std::move(surface));
}

IntSize
RasterImage::GetImageContainerSize(LayerManager* aManager,
                                   const IntSize& aSize,
                                   uint32_t aFlags)
{
  if (!IsImageContainerAvailableAtSize(aManager, aSize, aFlags)) {
    return IntSize(0, 0);
  }

  if (!CanDownscaleDuringDecode(aSize, aFlags)) {
    return mSize;
  }

  return aSize;
}

NS_IMETHODIMP_(bool)
RasterImage::IsImageContainerAvailable(LayerManager* aManager, uint32_t aFlags)
{
  return IsImageContainerAvailableAtSize(aManager, mSize, aFlags);
}

NS_IMETHODIMP_(already_AddRefed<ImageContainer>)
RasterImage::GetImageContainer(LayerManager* aManager, uint32_t aFlags)
{
  return GetImageContainerImpl(aManager, mSize, Nothing(), aFlags);
}

NS_IMETHODIMP_(bool)
RasterImage::IsImageContainerAvailableAtSize(LayerManager* aManager,
                                             const IntSize& aSize,
                                             uint32_t aFlags)
{
  // We check the minimum size because while we support downscaling, we do not
  // support upscaling. If aSize > mSize, we will never give a larger surface
  // than mSize. If mSize > aSize, and mSize > maxTextureSize, we still want to
  // use image containers if aSize <= maxTextureSize.
  int32_t maxTextureSize = aManager->GetMaxTextureSize();
  if (!mHasSize || aSize.IsEmpty() ||
      min(mSize.width, aSize.width) > maxTextureSize ||
      min(mSize.height, aSize.height) > maxTextureSize) {
    return false;
  }

  return true;
}

NS_IMETHODIMP_(already_AddRefed<ImageContainer>)
RasterImage::GetImageContainerAtSize(LayerManager* aManager,
                                     const IntSize& aSize,
                                     const Maybe<SVGImageContext>& aSVGContext,
                                     uint32_t aFlags)
{
  // We do not pass in the given SVG context because in theory it could differ
  // between calls, but actually have no impact on the actual contents of the
  // image container.
  return GetImageContainerImpl(aManager, aSize, Nothing(), aFlags);
}

size_t
RasterImage::SizeOfSourceWithComputedFallback(SizeOfState& aState) const
{
  return mSourceBuffer->SizeOfIncludingThisWithComputedFallback(
    aState.mMallocSizeOf);
}

void
RasterImage::CollectSizeOfSurfaces(nsTArray<SurfaceMemoryCounter>& aCounters,
                                   MallocSizeOf aMallocSizeOf) const
{
  SurfaceCache::CollectSizeOfSurfaces(ImageKey(this), aCounters, aMallocSizeOf);
  if (mFrameAnimator) {
    mFrameAnimator->CollectSizeOfCompositingSurfaces(aCounters, aMallocSizeOf);
  }
}

bool
RasterImage::SetMetadata(const ImageMetadata& aMetadata,
                         bool aFromMetadataDecode)
{
  MOZ_ASSERT(NS_IsMainThread());

  if (mError) {
    return true;
  }

  if (aMetadata.HasSize()) {
    IntSize size = aMetadata.GetSize();
    if (size.width < 0 || size.height < 0) {
      NS_WARNING("Image has negative intrinsic size");
      DoError();
      return true;
    }

    MOZ_ASSERT(aMetadata.HasOrientation());
    Orientation orientation = aMetadata.GetOrientation();

    // If we already have a size, check the new size against the old one.
    if (mHasSize && (size != mSize || orientation != mOrientation)) {
      NS_WARNING("Image changed size or orientation on redecode! "
                 "This should not happen!");
      DoError();
      return true;
    }

    // Set the size and flag that we have it.
    mSize = size;
    mOrientation = orientation;
    mNativeSizes = aMetadata.GetNativeSizes();
    mHasSize = true;
  }

  if (mHasSize && aMetadata.HasAnimation() && !mAnimationState) {
    // We're becoming animated, so initialize animation stuff.
    mAnimationState.emplace(mAnimationMode);
    mFrameAnimator = MakeUnique<FrameAnimator>(this, mSize);

    if (!gfxPrefs::ImageMemAnimatedDiscardable()) {
      // We don't support discarding animated images (See bug 414259).
      // Lock the image and throw away the key.
      LockImage();
    }

    if (!aFromMetadataDecode) {
      // The metadata decode reported that this image isn't animated, but we
      // discovered that it actually was during the full decode. This is a
      // rare failure that only occurs for corrupt images. To recover, we need
      // to discard all existing surfaces and redecode.
      return false;
    }
  }

  if (mAnimationState) {
    mAnimationState->SetLoopCount(aMetadata.GetLoopCount());
    mAnimationState->SetFirstFrameTimeout(aMetadata.GetFirstFrameTimeout());

    if (aMetadata.HasLoopLength()) {
      mAnimationState->SetLoopLength(aMetadata.GetLoopLength());
    }
    if (aMetadata.HasFirstFrameRefreshArea()) {
      mAnimationState
        ->SetFirstFrameRefreshArea(aMetadata.GetFirstFrameRefreshArea());
    }
  }

  if (aMetadata.HasHotspot()) {
    IntPoint hotspot = aMetadata.GetHotspot();

    nsCOMPtr<nsISupportsPRUint32> intwrapx =
      do_CreateInstance(NS_SUPPORTS_PRUINT32_CONTRACTID);
    nsCOMPtr<nsISupportsPRUint32> intwrapy =
      do_CreateInstance(NS_SUPPORTS_PRUINT32_CONTRACTID);
    intwrapx->SetData(hotspot.x);
    intwrapy->SetData(hotspot.y);

    Set("hotspotX", intwrapx);
    Set("hotspotY", intwrapy);
  }

  return true;
}

NS_IMETHODIMP
RasterImage::SetAnimationMode(uint16_t aAnimationMode)
{
  if (mAnimationState) {
    mAnimationState->SetAnimationMode(aAnimationMode);
  }
  return SetAnimationModeInternal(aAnimationMode);
}

//******************************************************************************

nsresult
RasterImage::StartAnimation()
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  MOZ_ASSERT(ShouldAnimate(), "Should not animate!");

  // If we're not ready to animate, then set mPendingAnimation, which will cause
  // us to start animating if and when we do become ready.
  mPendingAnimation = !mAnimationState || mAnimationState->KnownFrameCount() < 1;
  if (mPendingAnimation) {
    return NS_OK;
  }

  // Don't bother to animate if we're displaying the first frame forever.
  if (mAnimationState->GetCurrentAnimationFrameIndex() == 0 &&
      mAnimationState->FirstFrameTimeout() == FrameTimeout::Forever()) {
    mAnimationFinished = true;
    return NS_ERROR_ABORT;
  }

  // We need to set the time that this initial frame was first displayed, as
  // this is used in AdvanceFrame().
  mAnimationState->InitAnimationFrameTimeIfNecessary();

  return NS_OK;
}

//******************************************************************************
nsresult
RasterImage::StopAnimation()
{
  MOZ_ASSERT(mAnimating, "Should be animating!");

  nsresult rv = NS_OK;
  if (mError) {
    rv = NS_ERROR_FAILURE;
  } else {
    mAnimationState->SetAnimationFrameTime(TimeStamp());
  }

  mAnimating = false;
  return rv;
}

//******************************************************************************
NS_IMETHODIMP
RasterImage::ResetAnimation()
{
  if (mError) {
    return NS_ERROR_FAILURE;
    }

  mPendingAnimation = false;

  if (mAnimationMode == kDontAnimMode || !mAnimationState ||
      mAnimationState->GetCurrentAnimationFrameIndex() == 0) {
    return NS_OK;
  }

  mAnimationFinished = false;

  if (mAnimating) {
    StopAnimation();
  }

  MOZ_ASSERT(mAnimationState, "Should have AnimationState");
  MOZ_ASSERT(mFrameAnimator, "Should have FrameAnimator");
  mFrameAnimator->ResetAnimation(*mAnimationState);

  NotifyProgress(NoProgress, mAnimationState->FirstFrameRefreshArea());

  // Start the animation again. It may not have been running before, if
  // mAnimationFinished was true before entering this function.
  EvaluateAnimation();

  return NS_OK;
}

//******************************************************************************
NS_IMETHODIMP_(void)
RasterImage::SetAnimationStartTime(const TimeStamp& aTime)
{
  if (mError || mAnimationMode == kDontAnimMode || mAnimating || !mAnimationState) {
    return;
  }

  mAnimationState->SetAnimationFrameTime(aTime);
}

NS_IMETHODIMP_(float)
RasterImage::GetFrameIndex(uint32_t aWhichFrame)
{
  MOZ_ASSERT(aWhichFrame <= FRAME_MAX_VALUE, "Invalid argument");
  return (aWhichFrame == FRAME_FIRST || !mAnimationState)
         ? 0.0f
         : mAnimationState->GetCurrentAnimationFrameIndex();
}

NS_IMETHODIMP_(IntRect)
RasterImage::GetImageSpaceInvalidationRect(const IntRect& aRect)
{
  return aRect;
}

nsresult
RasterImage::OnImageDataComplete(nsIRequest*, nsISupports*, nsresult aStatus,
                                 bool aLastPart)
{
  MOZ_ASSERT(NS_IsMainThread());

  // Record that we have all the data we're going to get now.
  mAllSourceData = true;

  // Let decoders know that there won't be any more data coming.
  mSourceBuffer->Complete(aStatus);

  // Allow a synchronous metadata decode if mSyncLoad was set, or if we're
  // running on a single thread (in which case waiting for the async metadata
  // decoder could delay this image's load event quite a bit), or if this image
  // is transient.
  bool canSyncDecodeMetadata = mSyncLoad || mTransient ||
                               DecodePool::NumberOfCores() < 2;

  if (canSyncDecodeMetadata && !mHasSize) {
    // We're loading this image synchronously, so it needs to be usable after
    // this call returns.  Since we haven't gotten our size yet, we need to do a
    // synchronous metadata decode here.
    DecodeMetadata(FLAG_SYNC_DECODE);
  }

  // Determine our final status, giving precedence to Necko failure codes. We
  // check after running the metadata decode in case it triggered an error.
  nsresult finalStatus = mError ? NS_ERROR_FAILURE : NS_OK;
  if (NS_FAILED(aStatus)) {
    finalStatus = aStatus;
  }

  // If loading failed, report an error.
  if (NS_FAILED(finalStatus)) {
    DoError();
  }

  Progress loadProgress = LoadCompleteProgress(aLastPart, mError, finalStatus);

  if (!mHasSize && !mError) {
    // We don't have our size yet, so we'll fire the load event in SetSize().
    MOZ_ASSERT(!canSyncDecodeMetadata,
               "Firing load async after metadata sync decode?");
    mLoadProgress = Some(loadProgress);
    return finalStatus;
  }

  NotifyForLoadEvent(loadProgress);

  return finalStatus;
}

void
RasterImage::NotifyForLoadEvent(Progress aProgress)
{
  MOZ_ASSERT(mHasSize || mError, "Need to know size before firing load event");
  MOZ_ASSERT(!mHasSize ||
             (mProgressTracker->GetProgress() & FLAG_SIZE_AVAILABLE),
             "Should have notified that the size is available if we have it");

  // If we encountered an error, make sure we notify for that as well.
  if (mError) {
    aProgress |= FLAG_HAS_ERROR;
  }

  // Notify our listeners, which will fire this image's load event.
  NotifyProgress(aProgress);
}

nsresult
RasterImage::OnImageDataAvailable(nsIRequest*,
                                  nsISupports*,
                                  nsIInputStream* aInputStream,
                                  uint64_t,
                                  uint32_t aCount)
{
  nsresult rv = mSourceBuffer->AppendFromInputStream(aInputStream, aCount);
  if (NS_SUCCEEDED(rv) && !mSomeSourceData) {
    mSomeSourceData = true;
    if (!mSyncLoad) {
      // Create an async metadata decoder and verify we succeed in doing so.
      rv = DecodeMetadata(DECODE_FLAGS_DEFAULT);
    }
  }

  if (NS_FAILED(rv)) {
    DoError();
  }
  return rv;
}

nsresult
RasterImage::SetSourceSizeHint(uint32_t aSizeHint)
{
  if (aSizeHint == 0) {
    return NS_OK;
  }

  nsresult rv = mSourceBuffer->ExpectLength(aSizeHint);
  if (rv == NS_ERROR_OUT_OF_MEMORY) {
    // Flush memory, try to get some back, and try again.
    rv = nsMemory::HeapMinimize(true);
    if (NS_SUCCEEDED(rv)) {
      rv = mSourceBuffer->ExpectLength(aSizeHint);
    }
  }

  return rv;
}

/********* Methods to implement lazy allocation of nsIProperties object *******/
NS_IMETHODIMP
RasterImage::Get(const char* prop, const nsIID& iid, void** result)
{
  if (!mProperties) {
    return NS_ERROR_FAILURE;
  }
  return mProperties->Get(prop, iid, result);
}

NS_IMETHODIMP
RasterImage::Set(const char* prop, nsISupports* value)
{
  if (!mProperties) {
    mProperties = do_CreateInstance("@mozilla.org/properties;1");
  }
  if (!mProperties) {
    return NS_ERROR_OUT_OF_MEMORY;
  }
  return mProperties->Set(prop, value);
}

NS_IMETHODIMP
RasterImage::Has(const char* prop, bool* _retval)
{
  NS_ENSURE_ARG_POINTER(_retval);
  if (!mProperties) {
    *_retval = false;
    return NS_OK;
  }
  return mProperties->Has(prop, _retval);
}

NS_IMETHODIMP
RasterImage::Undefine(const char* prop)
{
  if (!mProperties) {
    return NS_ERROR_FAILURE;
  }
  return mProperties->Undefine(prop);
}

NS_IMETHODIMP
RasterImage::GetKeys(uint32_t* count, char*** keys)
{
  if (!mProperties) {
    *count = 0;
    *keys = nullptr;
    return NS_OK;
  }
  return mProperties->GetKeys(count, keys);
}

void
RasterImage::Discard()
{
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(CanDiscard(), "Asked to discard but can't");
  MOZ_ASSERT(!mAnimationState || gfxPrefs::ImageMemAnimatedDiscardable(),
    "Asked to discard for animated image");

  // Delete all the decoded frames.
  SurfaceCache::RemoveImage(ImageKey(this));

  if (mAnimationState) {
    ReleaseImageContainer();
    gfx::IntRect rect =
      mAnimationState->UpdateState(mAnimationFinished, this, mSize);
    NotifyProgress(NoProgress, rect);
  }

  // Notify that we discarded.
  if (mProgressTracker) {
    mProgressTracker->OnDiscard();
  }
}

bool
RasterImage::CanDiscard() {
  return mAllSourceData &&
         // Can discard animated images if the pref is set
         (!mAnimationState || gfxPrefs::ImageMemAnimatedDiscardable());
}

NS_IMETHODIMP
RasterImage::StartDecoding(uint32_t aFlags)
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  if (!mHasSize) {
    mWantFullDecode = true;
    return NS_OK;
  }

  uint32_t flags = (aFlags & FLAG_ASYNC_NOTIFY) | FLAG_SYNC_DECODE_IF_FAST;
  return RequestDecodeForSize(mSize, flags);
}

bool
RasterImage::StartDecodingWithResult(uint32_t aFlags)
{
  if (mError) {
    return false;
  }

  if (!mHasSize) {
    mWantFullDecode = true;
    return false;
  }

  uint32_t flags = (aFlags & FLAG_ASYNC_NOTIFY) | FLAG_SYNC_DECODE_IF_FAST;
  DrawableSurface surface = RequestDecodeForSizeInternal(mSize, flags);
  return surface && surface->IsFinished();
}

NS_IMETHODIMP
RasterImage::RequestDecodeForSize(const IntSize& aSize, uint32_t aFlags)
{
  MOZ_ASSERT(NS_IsMainThread());

  if (mError) {
    return NS_ERROR_FAILURE;
  }

  RequestDecodeForSizeInternal(aSize, aFlags);

  return NS_OK;
}

DrawableSurface
RasterImage::RequestDecodeForSizeInternal(const IntSize& aSize, uint32_t aFlags)
{
  MOZ_ASSERT(NS_IsMainThread());

  if (mError) {
    return DrawableSurface();
  }

  if (!mHasSize) {
    mWantFullDecode = true;
    return DrawableSurface();
  }

  // Decide whether to sync decode images we can decode quickly. Here we are
  // explicitly trading off flashing for responsiveness in the case that we're
  // redecoding an image (see bug 845147).
  bool shouldSyncDecodeIfFast =
    !mHasBeenDecoded && (aFlags & FLAG_SYNC_DECODE_IF_FAST);

  uint32_t flags = shouldSyncDecodeIfFast
                 ? aFlags
                 : aFlags & ~FLAG_SYNC_DECODE_IF_FAST;

  // Perform a frame lookup, which will implicitly start decoding if needed.
  PlaybackType playbackType = mAnimationState ? PlaybackType::eAnimated
                                              : PlaybackType::eStatic;
  LookupResult result = LookupFrame(aSize, flags, playbackType);
  return std::move(result.Surface());
}

static bool
LaunchDecodingTask(IDecodingTask* aTask,
                   RasterImage* aImage,
                   uint32_t aFlags,
                   bool aHaveSourceData)
{
  if (aHaveSourceData) {
    nsCString uri(aImage->GetURIString());

    // If we have all the data, we can sync decode if requested.
    if (aFlags & imgIContainer::FLAG_SYNC_DECODE) {
      DecodePool::Singleton()->SyncRunIfPossible(aTask, uri);
      return true;
    }

    if (aFlags & imgIContainer::FLAG_SYNC_DECODE_IF_FAST) {
      return DecodePool::Singleton()->SyncRunIfPreferred(aTask, uri);
    }
  }

  // Perform an async decode. We also take this path if we don't have all the
  // source data yet, since sync decoding is impossible in that situation.
  DecodePool::Singleton()->AsyncRun(aTask);
  return false;
}

bool
RasterImage::Decode(const IntSize& aSize,
                    uint32_t aFlags,
                    PlaybackType aPlaybackType)
{
  MOZ_ASSERT(NS_IsMainThread());

  if (mError) {
    return false;
  }

  // If we don't have a size yet, we can't do any other decoding.
  if (!mHasSize) {
    mWantFullDecode = true;
    return false;
  }

  // We're about to decode again, which may mean that some of the previous sizes
  // we've decoded at aren't useful anymore. We can allow them to expire from
  // the cache by unlocking them here. When the decode finishes, it will send an
  // invalidation that will cause all instances of this image to redraw. If this
  // image is locked, any surfaces that are still useful will become locked
  // again when LookupFrame touches them, and the remainder will eventually
  // expire.
  SurfaceCache::UnlockEntries(ImageKey(this));

  // Determine which flags we need to decode this image with.
  DecoderFlags decoderFlags = DefaultDecoderFlags();
  if (aFlags & FLAG_ASYNC_NOTIFY) {
    decoderFlags |= DecoderFlags::ASYNC_NOTIFY;
  }
  if (mTransient) {
    decoderFlags |= DecoderFlags::IMAGE_IS_TRANSIENT;
  }
  if (mHasBeenDecoded) {
    decoderFlags |= DecoderFlags::IS_REDECODE;
  }
  if ((aFlags & FLAG_SYNC_DECODE) || !(aFlags & FLAG_HIGH_QUALITY_SCALING)) {
    // Used SurfaceCache::Lookup instead of SurfaceCache::LookupBestMatch. That
    // means the caller can handle a differently sized surface to be returned
    // at any point.
    decoderFlags |= DecoderFlags::CANNOT_SUBSTITUTE;
  }

  SurfaceFlags surfaceFlags = ToSurfaceFlags(aFlags);
  if (IsOpaque()) {
    // If there's no transparency, it doesn't matter whether we premultiply
    // alpha or not.
    surfaceFlags &= ~SurfaceFlags::NO_PREMULTIPLY_ALPHA;
  }

  // Create a decoder.
  RefPtr<IDecodingTask> task;
  nsresult rv;
  bool animated = mAnimationState && aPlaybackType == PlaybackType::eAnimated;
  if (animated) {
    size_t currentFrame = mAnimationState->GetCurrentAnimationFrameIndex();
    rv = DecoderFactory::CreateAnimationDecoder(mDecoderType, WrapNotNull(this),
                                                mSourceBuffer, mSize,
                                                decoderFlags, surfaceFlags,
                                                currentFrame,
                                                getter_AddRefs(task));
  } else {
    rv = DecoderFactory::CreateDecoder(mDecoderType, WrapNotNull(this),
                                       mSourceBuffer, mSize, aSize,
                                       decoderFlags, surfaceFlags,
                                       getter_AddRefs(task));
  }

  if (rv == NS_ERROR_ALREADY_INITIALIZED) {
    // We raced with an already pending decoder, and it finished before we
    // managed to insert the new decoder. Pretend we did a sync call to make
    // the caller lookup in the surface cache again.
    MOZ_ASSERT(!task);
    return true;
  }

  if (animated) {
    // We pass false for aAllowInvalidation because we may be asked to use
    // async notifications. Any potential invalidation here will be sent when
    // RequestRefresh is called, or NotifyDecodeComplete.
#ifdef DEBUG
    gfx::IntRect rect =
#endif
      mAnimationState->UpdateState(mAnimationFinished, this, mSize, false);
    MOZ_ASSERT(rect.IsEmpty());
  }

  // Make sure DecoderFactory was able to create a decoder successfully.
  if (NS_FAILED(rv)) {
    MOZ_ASSERT(!task);
    return false;
  }

  MOZ_ASSERT(task);
  mDecodeCount++;

  // We're ready to decode; start the decoder.
  return LaunchDecodingTask(task, this, aFlags, mAllSourceData);
}

NS_IMETHODIMP
RasterImage::DecodeMetadata(uint32_t aFlags)
{
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  MOZ_ASSERT(!mHasSize, "Should not do unnecessary metadata decodes");

  // Create a decoder.
  RefPtr<IDecodingTask> task =
    DecoderFactory::CreateMetadataDecoder(mDecoderType, WrapNotNull(this),
                                          mSourceBuffer);

  // Make sure DecoderFactory was able to create a decoder successfully.
  if (!task) {
    return NS_ERROR_FAILURE;
  }

  // We're ready to decode; start the decoder.
  LaunchDecodingTask(task, this, aFlags, mAllSourceData);
  return NS_OK;
}

void
RasterImage::RecoverFromInvalidFrames(const IntSize& aSize, uint32_t aFlags)
{
  if (!mHasSize) {
    return;
  }

  NS_WARNING("A RasterImage's frames became invalid. Attempting to recover...");

  // Discard all existing frames, since they're probably all now invalid.
  SurfaceCache::RemoveImage(ImageKey(this));

  // Relock the image if it's supposed to be locked.
  if (mLockCount > 0) {
    SurfaceCache::LockImage(ImageKey(this));
  }

  // Animated images require some special handling, because we normally require
  // that they never be discarded.
  if (mAnimationState) {
    Decode(mSize, aFlags | FLAG_SYNC_DECODE, PlaybackType::eAnimated);
    ResetAnimation();
    return;
  }

  // For non-animated images, it's fine to recover using an async decode.
  Decode(aSize, aFlags, PlaybackType::eStatic);
}

static bool
HaveSkia()
{
#ifdef MOZ_ENABLE_SKIA
  return true;
#else
  return false;
#endif
}

bool
RasterImage::CanDownscaleDuringDecode(const IntSize& aSize, uint32_t aFlags)
{
  // Check basic requirements: downscale-during-decode is enabled, Skia is
  // available, this image isn't transient, we have all the source data and know
  // our size, and the flags allow us to do it.
  if (!mHasSize || mTransient || !HaveSkia() ||
      !gfxPrefs::ImageDownscaleDuringDecodeEnabled() ||
      !(aFlags & imgIContainer::FLAG_HIGH_QUALITY_SCALING)) {
    return false;
  }

  // We don't downscale animated images during decode.
  if (mAnimationState) {
    return false;
  }

  // Never upscale.
  if (aSize.width >= mSize.width || aSize.height >= mSize.height) {
    return false;
  }

  // Zero or negative width or height is unacceptable.
  if (aSize.width < 1 || aSize.height < 1) {
    return false;
  }

  // There's no point in scaling if we can't store the result.
  if (!SurfaceCache::CanHold(aSize)) {
    return false;
  }

  return true;
}

ImgDrawResult
RasterImage::DrawInternal(DrawableSurface&& aSurface,
                          gfxContext* aContext,
                          const IntSize& aSize,
                          const ImageRegion& aRegion,
                          SamplingFilter aSamplingFilter,
                          uint32_t aFlags,
                          float aOpacity)
{
  gfxContextMatrixAutoSaveRestore saveMatrix(aContext);
  ImageRegion region(aRegion);
  bool frameIsFinished = aSurface->IsFinished();

#ifdef DEBUG
  NotifyDrawingObservers();
#endif

  // By now we may have a frame with the requested size. If not, we need to
  // adjust the drawing parameters accordingly.
  IntSize finalSize = aSurface->GetImageSize();
  bool couldRedecodeForBetterFrame = false;
  if (finalSize != aSize) {
    gfx::Size scale(double(aSize.width) / finalSize.width,
                    double(aSize.height) / finalSize.height);
    aContext->Multiply(gfxMatrix::Scaling(scale.width, scale.height));
    region.Scale(1.0 / scale.width, 1.0 / scale.height);

    couldRedecodeForBetterFrame = CanDownscaleDuringDecode(aSize, aFlags);
  }

  if (!aSurface->Draw(aContext, region, aSamplingFilter, aFlags, aOpacity)) {
    RecoverFromInvalidFrames(aSize, aFlags);
    return ImgDrawResult::TEMPORARY_ERROR;
  }
  if (!frameIsFinished) {
    return ImgDrawResult::INCOMPLETE;
  }
  if (couldRedecodeForBetterFrame) {
    return ImgDrawResult::WRONG_SIZE;
  }
  return ImgDrawResult::SUCCESS;
}

//******************************************************************************
NS_IMETHODIMP_(ImgDrawResult)
RasterImage::Draw(gfxContext* aContext,
                  const IntSize& aSize,
                  const ImageRegion& aRegion,
                  uint32_t aWhichFrame,
                  SamplingFilter aSamplingFilter,
                  const Maybe<SVGImageContext>& /*aSVGContext - ignored*/,
                  uint32_t aFlags,
                  float aOpacity)
{
  if (aWhichFrame > FRAME_MAX_VALUE) {
    return ImgDrawResult::BAD_ARGS;
  }

  if (mError) {
    return ImgDrawResult::BAD_IMAGE;
  }

  // Illegal -- you can't draw with non-default decode flags.
  // (Disabling colorspace conversion might make sense to allow, but
  // we don't currently.)
  if (ToSurfaceFlags(aFlags) != DefaultSurfaceFlags()) {
    return ImgDrawResult::BAD_ARGS;
  }

  if (!aContext) {
    return ImgDrawResult::BAD_ARGS;
  }

  if (mAnimationConsumers == 0) {
    SendOnUnlockedDraw(aFlags);
  }


  // If we're not using SamplingFilter::GOOD, we shouldn't high-quality scale or
  // downscale during decode.
  uint32_t flags = aSamplingFilter == SamplingFilter::GOOD
                 ? aFlags
                 : aFlags & ~FLAG_HIGH_QUALITY_SCALING;

  LookupResult result =
    LookupFrame(aSize, flags, ToPlaybackType(aWhichFrame));
  if (!result) {
    // Getting the frame (above) touches the image and kicks off decoding.
    if (mDrawStartTime.IsNull()) {
      mDrawStartTime = TimeStamp::Now();
    }
    return ImgDrawResult::NOT_READY;
  }

  bool shouldRecordTelemetry = !mDrawStartTime.IsNull() &&
                               result.Surface()->IsFinished();

  auto drawResult = DrawInternal(std::move(result.Surface()), aContext, aSize,
                                 aRegion, aSamplingFilter, flags, aOpacity);

  if (shouldRecordTelemetry) {
      TimeDuration drawLatency = TimeStamp::Now() - mDrawStartTime;
      Telemetry::Accumulate(Telemetry::IMAGE_DECODE_ON_DRAW_LATENCY,
                            int32_t(drawLatency.ToMicroseconds()));
      mDrawStartTime = TimeStamp();
  }

  return drawResult;
}

//******************************************************************************

NS_IMETHODIMP
RasterImage::LockImage()
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Main thread to encourage serialization with UnlockImage");
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  // Increment the lock count
  mLockCount++;

  // Lock this image's surfaces in the SurfaceCache.
  if (mLockCount == 1) {
    SurfaceCache::LockImage(ImageKey(this));
  }

  return NS_OK;
}

//******************************************************************************

NS_IMETHODIMP
RasterImage::UnlockImage()
{
  MOZ_ASSERT(NS_IsMainThread(),
             "Main thread to encourage serialization with LockImage");
  if (mError) {
    return NS_ERROR_FAILURE;
  }

  // It's an error to call this function if the lock count is 0
  MOZ_ASSERT(mLockCount > 0,
             "Calling UnlockImage with mLockCount == 0!");
  if (mLockCount == 0) {
    return NS_ERROR_ABORT;
  }

  // Decrement our lock count
  mLockCount--;

  // Unlock this image's surfaces in the SurfaceCache.
  if (mLockCount == 0 ) {
    SurfaceCache::UnlockImage(ImageKey(this));
  }

  return NS_OK;
}

//******************************************************************************

NS_IMETHODIMP
RasterImage::RequestDiscard()
{
  if (mDiscardable &&      // Enabled at creation time...
      mLockCount == 0 &&   // ...not temporarily disabled...
      CanDiscard()) {
    Discard();
  }

  return NS_OK;
}

// Indempotent error flagging routine. If a decoder is open, shuts it down.
void
RasterImage::DoError()
{
  // If we've flagged an error before, we have nothing to do
  if (mError) {
    return;
  }

  // We can't safely handle errors off-main-thread, so dispatch a worker to
  // do it.
  if (!NS_IsMainThread()) {
    HandleErrorWorker::DispatchIfNeeded(this);
    return;
  }

  // Put the container in an error state.
  mError = true;

  // Stop animation and release our FrameAnimator.
  if (mAnimating) {
    StopAnimation();
  }
  mAnimationState = Nothing();
  mFrameAnimator = nullptr;

  // Release all locks.
  mLockCount = 0;
  SurfaceCache::UnlockImage(ImageKey(this));

  // Release all frames from the surface cache.
  SurfaceCache::RemoveImage(ImageKey(this));

  // Invalidate to get rid of any partially-drawn image content.
  NotifyProgress(NoProgress, IntRect(0, 0, mSize.width, mSize.height));

  MOZ_LOG(gImgLog, LogLevel::Error,
          ("RasterImage: [this=%p] Error detected for image\n", this));
}

/* static */ void
RasterImage::HandleErrorWorker::DispatchIfNeeded(RasterImage* aImage)
{
  RefPtr<HandleErrorWorker> worker = new HandleErrorWorker(aImage);
  NS_DispatchToMainThread(worker);
}

RasterImage::HandleErrorWorker::HandleErrorWorker(RasterImage* aImage)
  : Runnable("image::RasterImage::HandleErrorWorker")
  , mImage(aImage)
{
  MOZ_ASSERT(mImage, "Should have image");
}

NS_IMETHODIMP
RasterImage::HandleErrorWorker::Run()
{
  mImage->DoError();

  return NS_OK;
}

bool
RasterImage::ShouldAnimate()
{
  return ImageResource::ShouldAnimate() &&
         mAnimationState &&
         mAnimationState->KnownFrameCount() >= 1 &&
         !mAnimationFinished;
}

#ifdef DEBUG
NS_IMETHODIMP
RasterImage::GetFramesNotified(uint32_t* aFramesNotified)
{
  NS_ENSURE_ARG_POINTER(aFramesNotified);

  *aFramesNotified = mFramesNotified;

  return NS_OK;
}
#endif

void
RasterImage::NotifyProgress(Progress aProgress,
                            const IntRect& aInvalidRect /* = IntRect() */,
                            const Maybe<uint32_t>& aFrameCount /* = Nothing() */,
                            DecoderFlags aDecoderFlags
                              /* = DefaultDecoderFlags() */,
                            SurfaceFlags aSurfaceFlags
                              /* = DefaultSurfaceFlags() */)
{
  MOZ_ASSERT(NS_IsMainThread());

  // Ensure that we stay alive long enough to finish notifying.
  RefPtr<RasterImage> image = this;

  const bool wasDefaultFlags = aSurfaceFlags == DefaultSurfaceFlags();

  if (!aInvalidRect.IsEmpty() && wasDefaultFlags) {
    // Update our image container since we're invalidating.
    UpdateImageContainer();
  }

  if (!(aDecoderFlags & DecoderFlags::FIRST_FRAME_ONLY)) {
    // We may have decoded new animation frames; update our animation state.
    MOZ_ASSERT_IF(aFrameCount && *aFrameCount > 1, mAnimationState || mError);
    if (mAnimationState && aFrameCount) {
      mAnimationState->UpdateKnownFrameCount(*aFrameCount);
    }

    // If we should start animating right now, do so.
    if (mAnimationState && aFrameCount == Some(1u) &&
        mPendingAnimation && ShouldAnimate()) {
      StartAnimation();
    }
  }

  // Tell the observers what happened.
  image->mProgressTracker->SyncNotifyProgress(aProgress, aInvalidRect);
}

void
RasterImage::NotifyDecodeComplete(const DecoderFinalStatus& aStatus,
                                  const ImageMetadata& aMetadata,
                                  const DecoderTelemetry& aTelemetry,
                                  Progress aProgress,
                                  const IntRect& aInvalidRect,
                                  const Maybe<uint32_t>& aFrameCount,
                                  DecoderFlags aDecoderFlags,
                                  SurfaceFlags aSurfaceFlags)
{
  MOZ_ASSERT(NS_IsMainThread());

  // If the decoder detected an error, log it to the error console.
  if (aStatus.mShouldReportError) {
    ReportDecoderError();
  }

  // Record all the metadata the decoder gathered about this image.
  bool metadataOK = SetMetadata(aMetadata, aStatus.mWasMetadataDecode);
  if (!metadataOK) {
    // This indicates a serious error that requires us to discard all existing
    // surfaces and redecode to recover. We'll drop the results from this
    // decoder on the floor, since they aren't valid.
    RecoverFromInvalidFrames(mSize,
                             FromSurfaceFlags(aSurfaceFlags));
    return;
  }

  MOZ_ASSERT(mError || mHasSize || !aMetadata.HasSize(),
             "SetMetadata should've gotten a size");

  if (!aStatus.mWasMetadataDecode && aStatus.mFinished) {
    // Flag that we've been decoded before.
    mHasBeenDecoded = true;
  }

  // Send out any final notifications.
  NotifyProgress(aProgress, aInvalidRect, aFrameCount,
                 aDecoderFlags, aSurfaceFlags);

  if (!(aDecoderFlags & DecoderFlags::FIRST_FRAME_ONLY) &&
      mHasBeenDecoded && mAnimationState) {
    // We've finished a full decode of all animation frames and our AnimationState
    // has been notified about them all, so let it know not to expect anymore.
    mAnimationState->NotifyDecodeComplete();
    gfx::IntRect rect = mAnimationState->UpdateState(mAnimationFinished, this, mSize);
    if (!rect.IsEmpty()) {
      NotifyProgress(NoProgress, rect);
    }
  }

  // Do some telemetry if this isn't a metadata decode.
  if (!aStatus.mWasMetadataDecode) {
    if (aTelemetry.mChunkCount) {
      Telemetry::Accumulate(Telemetry::IMAGE_DECODE_CHUNKS, aTelemetry.mChunkCount);
    }

    if (aStatus.mFinished) {
      Telemetry::Accumulate(Telemetry::IMAGE_DECODE_TIME,
                            int32_t(aTelemetry.mDecodeTime.ToMicroseconds()));

      if (aTelemetry.mSpeedHistogram && aTelemetry.mBytesDecoded) {
        Telemetry::Accumulate(*aTelemetry.mSpeedHistogram, aTelemetry.Speed());
      }
    }
  }

  // Only act on errors if we have no usable frames from the decoder.
  if (aStatus.mHadError &&
      (!mAnimationState || mAnimationState->KnownFrameCount() == 0)) {
    DoError();
  } else if (aStatus.mWasMetadataDecode && !mHasSize) {
    DoError();
  }

  // XXX(aosmond): Can we get this far without mFinished == true?
  if (aStatus.mFinished && aStatus.mWasMetadataDecode) {
    // If we were waiting to fire the load event, go ahead and fire it now.
    if (mLoadProgress) {
      NotifyForLoadEvent(*mLoadProgress);
      mLoadProgress = Nothing();
    }

    // If we were a metadata decode and a full decode was requested, do it.
    if (mWantFullDecode) {
      mWantFullDecode = false;
      RequestDecodeForSize(mSize, DECODE_FLAGS_DEFAULT);
    }
  }
}

void
RasterImage::ReportDecoderError()
{
  nsCOMPtr<nsIConsoleService> consoleService =
    do_GetService(NS_CONSOLESERVICE_CONTRACTID);
  nsCOMPtr<nsIScriptError> errorObject =
    do_CreateInstance(NS_SCRIPTERROR_CONTRACTID);

  if (consoleService && errorObject) {
    nsAutoString msg(NS_LITERAL_STRING("Image corrupt or truncated."));
    nsAutoString src;
    if (GetURI()) {
      nsAutoCString uri;
      if (!GetSpecTruncatedTo1k(uri)) {
        msg += NS_LITERAL_STRING(" URI in this note truncated due to length.");
      }
      src = NS_ConvertUTF8toUTF16(uri);
    }
    if (NS_SUCCEEDED(errorObject->InitWithWindowID(
                       msg,
                       src,
                       EmptyString(), 0, 0, nsIScriptError::errorFlag,
                       "Image", InnerWindowID()
                     ))) {
      consoleService->LogMessage(errorObject);
    }
  }
}

already_AddRefed<imgIContainer>
RasterImage::Unwrap()
{
  nsCOMPtr<imgIContainer> self(this);
  return self.forget();
}

void
RasterImage::PropagateUseCounters(nsIDocument*)
{
  // No use counters.
}

IntSize
RasterImage::OptimalImageSizeForDest(const gfxSize& aDest, uint32_t aWhichFrame,
                                     SamplingFilter aSamplingFilter, uint32_t aFlags)
{
  MOZ_ASSERT(aDest.width >= 0 || ceil(aDest.width) <= INT32_MAX ||
             aDest.height >= 0 || ceil(aDest.height) <= INT32_MAX,
             "Unexpected destination size");

  if (mSize.IsEmpty() || aDest.IsEmpty()) {
    return IntSize(0, 0);
  }

  IntSize destSize = IntSize::Ceil(aDest.width, aDest.height);

  if (aSamplingFilter == SamplingFilter::GOOD &&
      CanDownscaleDuringDecode(destSize, aFlags)) {
    return destSize;
  }

  // We can't scale to this size. Use our intrinsic size for now.
  return mSize;
}

} // namespace image
} // namespace mozilla