gecko-dev/image/AnimationSurfaceProvider.cpp

294 lines
8.9 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 "AnimationSurfaceProvider.h"
#include "gfxPrefs.h"
#include "nsProxyRelease.h"
#include "Decoder.h"
using namespace mozilla::gfx;
namespace mozilla {
namespace image {
AnimationSurfaceProvider::AnimationSurfaceProvider(NotNull<RasterImage*> aImage,
const SurfaceKey& aSurfaceKey,
NotNull<Decoder*> aDecoder)
: ISurfaceProvider(ImageKey(aImage.get()), aSurfaceKey,
AvailabilityState::StartAsPlaceholder())
, mImage(aImage.get())
, mDecodingMutex("AnimationSurfaceProvider::mDecoder")
, mDecoder(aDecoder.get())
, mFramesMutex("AnimationSurfaceProvider::mFrames")
{
MOZ_ASSERT(!mDecoder->IsMetadataDecode(),
"Use MetadataDecodingTask for metadata decodes");
MOZ_ASSERT(!mDecoder->IsFirstFrameDecode(),
"Use DecodedSurfaceProvider for single-frame image decodes");
}
AnimationSurfaceProvider::~AnimationSurfaceProvider()
{
DropImageReference();
}
void
AnimationSurfaceProvider::DropImageReference()
{
if (!mImage) {
return; // Nothing to do.
}
// RasterImage objects need to be destroyed on the main thread. We also need
// to destroy them asynchronously, because if our surface cache entry is
// destroyed and we were the only thing keeping |mImage| alive, RasterImage's
// destructor may call into the surface cache while whatever code caused us to
// get evicted is holding the surface cache lock, causing deadlock.
RefPtr<RasterImage> image = mImage;
mImage = nullptr;
NS_ReleaseOnMainThreadSystemGroup(image.forget(), /* aAlwaysProxy = */ true);
}
DrawableFrameRef
AnimationSurfaceProvider::DrawableRef(size_t aFrame)
{
MutexAutoLock lock(mFramesMutex);
if (Availability().IsPlaceholder()) {
MOZ_ASSERT_UNREACHABLE("Calling DrawableRef() on a placeholder");
return DrawableFrameRef();
}
if (mFrames.IsEmpty()) {
MOZ_ASSERT_UNREACHABLE("Calling DrawableRef() when we have no frames");
return DrawableFrameRef();
}
// If we don't have that frame, return an empty frame ref.
if (aFrame >= mFrames.Length()) {
return DrawableFrameRef();
}
// We've got the requested frame. Return it.
MOZ_ASSERT(mFrames[aFrame]);
return mFrames[aFrame]->DrawableRef();
}
bool
AnimationSurfaceProvider::IsFinished() const
{
MutexAutoLock lock(mFramesMutex);
if (Availability().IsPlaceholder()) {
MOZ_ASSERT_UNREACHABLE("Calling IsFinished() on a placeholder");
return false;
}
if (mFrames.IsEmpty()) {
MOZ_ASSERT_UNREACHABLE("Calling IsFinished() when we have no frames");
return false;
}
// As long as we have at least one finished frame, we're finished.
return mFrames[0]->IsFinished();
}
size_t
AnimationSurfaceProvider::LogicalSizeInBytes() const
{
// When decoding animated images, we need at most three live surfaces: the
// composited surface, the previous composited surface for
// DisposalMethod::RESTORE_PREVIOUS, and the surface we're currently decoding
// into. The composited surfaces are always BGRA. Although the surface we're
// decoding into may be paletted, and may be smaller than the real size of the
// image, we assume the worst case here.
// XXX(seth): Note that this is actually not accurate yet; we're storing the
// full sequence of frames, not just the three live surfaces mentioned above.
// Unfortunately there's no way to know in advance how many frames an
// animation has, so we really can't do better here. This will become correct
// once bug 1289954 is complete.
IntSize size = GetSurfaceKey().Size();
return 3 * size.width * size.height * sizeof(uint32_t);
}
void
AnimationSurfaceProvider::AddSizeOfExcludingThis(MallocSizeOf aMallocSizeOf,
size_t& aHeapSizeOut,
size_t& aNonHeapSizeOut,
size_t& aSharedHandlesOut)
{
// Note that the surface cache lock is already held here, and then we acquire
// mFramesMutex. For this method, this ordering is unavoidable, which means
// that we must be careful to always use the same ordering elsewhere.
MutexAutoLock lock(mFramesMutex);
for (const RawAccessFrameRef& frame : mFrames) {
frame->AddSizeOfExcludingThis(aMallocSizeOf, aHeapSizeOut,
aNonHeapSizeOut, aSharedHandlesOut);
}
}
void
AnimationSurfaceProvider::Run()
{
MutexAutoLock lock(mDecodingMutex);
if (!mDecoder || !mImage) {
MOZ_ASSERT_UNREACHABLE("Running after decoding finished?");
return;
}
while (true) {
// Run the decoder.
LexerResult result = mDecoder->Decode(WrapNotNull(this));
if (result.is<TerminalState>()) {
// We may have a new frame now, but it's not guaranteed - a decoding
// failure or truncated data may mean that no new frame got produced.
// Since we're not sure, rather than call CheckForNewFrameAtYield() here
// we call CheckForNewFrameAtTerminalState(), which handles both of these
// possibilities.
CheckForNewFrameAtTerminalState();
// We're done!
FinishDecoding();
return;
}
// Notify for the progress we've made so far.
if (mDecoder->HasProgress()) {
NotifyProgress(WrapNotNull(mImage), WrapNotNull(mDecoder));
}
if (result == LexerResult(Yield::NEED_MORE_DATA)) {
// We can't make any more progress right now. The decoder itself will ensure
// that we get reenqueued when more data is available; just return for now.
return;
}
// There's new output available - a new frame! Grab it.
MOZ_ASSERT(result == LexerResult(Yield::OUTPUT_AVAILABLE));
CheckForNewFrameAtYield();
}
}
void
AnimationSurfaceProvider::CheckForNewFrameAtYield()
{
mDecodingMutex.AssertCurrentThreadOwns();
MOZ_ASSERT(mDecoder);
bool justGotFirstFrame = false;
{
MutexAutoLock lock(mFramesMutex);
// Try to get the new frame from the decoder.
RawAccessFrameRef frame = mDecoder->GetCurrentFrameRef();
if (!frame) {
MOZ_ASSERT_UNREACHABLE("Decoder yielded but didn't produce a frame?");
return;
}
// We should've gotten a different frame than last time.
MOZ_ASSERT_IF(!mFrames.IsEmpty(),
mFrames.LastElement().get() != frame.get());
// Append the new frame to the list.
mFrames.AppendElement(Move(frame));
if (mFrames.Length() == 1) {
justGotFirstFrame = true;
}
}
if (justGotFirstFrame) {
AnnounceSurfaceAvailable();
}
}
void
AnimationSurfaceProvider::CheckForNewFrameAtTerminalState()
{
mDecodingMutex.AssertCurrentThreadOwns();
MOZ_ASSERT(mDecoder);
bool justGotFirstFrame = false;
{
MutexAutoLock lock(mFramesMutex);
RawAccessFrameRef frame = mDecoder->GetCurrentFrameRef();
if (!frame) {
return;
}
if (!mFrames.IsEmpty() && mFrames.LastElement().get() == frame.get()) {
return; // We already have this one.
}
// Append the new frame to the list.
mFrames.AppendElement(Move(frame));
if (mFrames.Length() == 1) {
justGotFirstFrame = true;
}
}
if (justGotFirstFrame) {
AnnounceSurfaceAvailable();
}
}
void
AnimationSurfaceProvider::AnnounceSurfaceAvailable()
{
mFramesMutex.AssertNotCurrentThreadOwns();
MOZ_ASSERT(mImage);
// We just got the first frame; let the surface cache know. We deliberately do
// this outside of mFramesMutex to avoid a potential deadlock with
// AddSizeOfExcludingThis(), since otherwise we'd be acquiring mFramesMutex
// and then the surface cache lock, while the memory reporting code would
// acquire the surface cache lock and then mFramesMutex.
SurfaceCache::SurfaceAvailable(WrapNotNull(this));
}
void
AnimationSurfaceProvider::FinishDecoding()
{
mDecodingMutex.AssertCurrentThreadOwns();
MOZ_ASSERT(mImage);
MOZ_ASSERT(mDecoder);
// Send notifications.
NotifyDecodeComplete(WrapNotNull(mImage), WrapNotNull(mDecoder));
// Destroy our decoder; we don't need it anymore.
mDecoder = nullptr;
// We don't need a reference to our image anymore, either, and we don't want
// one. We may be stored in the surface cache for a long time after decoding
// finishes. If we don't drop our reference to the image, we'll end up
// keeping it alive as long as we remain in the surface cache, which could
// greatly extend the image's lifetime - in fact, if the image isn't
// discardable, it'd result in a leak!
DropImageReference();
}
bool
AnimationSurfaceProvider::ShouldPreferSyncRun() const
{
MutexAutoLock lock(mDecodingMutex);
MOZ_ASSERT(mDecoder);
return mDecoder->ShouldSyncDecode(gfxPrefs::ImageMemDecodeBytesAtATime());
}
} // namespace image
} // namespace mozilla