/* -*- 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 "IDecodingTask.h" #include "nsThreadUtils.h" #include "Decoder.h" #include "DecodePool.h" #include "RasterImage.h" #include "SurfaceCache.h" namespace mozilla { using gfx::IntRect; namespace image { /////////////////////////////////////////////////////////////////////////////// // Helpers for sending notifications to the image associated with a decoder. /////////////////////////////////////////////////////////////////////////////// void IDecodingTask::EnsureHasEventTarget(NotNull aImage) { if (!mEventTarget) { // We determine the event target as late as possible, at the first dispatch // time, because the observers bound to an imgRequest will affect it. // We cache it rather than query for the event target each time because the // event target can change. We don't want to risk events being executed in // a different order than they are dispatched, which can happen if we // selected scheduler groups which have no ordering guarantees relative to // each other (e.g. it moves from scheduler group A for doc group DA to // scheduler group B for doc group DB due to changing observers -- if we // dispatched the first event on A, and the second on B, we don't know which // will execute first.) RefPtr tracker = aImage->GetProgressTracker(); if (tracker) { mEventTarget = tracker->GetEventTarget(); } else { mEventTarget = GetMainThreadSerialEventTarget(); } } } bool IDecodingTask::IsOnEventTarget() const { // This is essentially equivalent to NS_IsOnMainThread() because all of the // event targets are for the main thread (although perhaps with a different // label / scheduler group). The observers in ProgressTracker may have // different event targets from this, so this is just a best effort guess. bool current = false; mEventTarget->IsOnCurrentThread(¤t); return current; } void IDecodingTask::NotifyProgress(NotNull aImage, NotNull aDecoder) { MOZ_ASSERT(aDecoder->HasProgress() && !aDecoder->IsMetadataDecode()); EnsureHasEventTarget(aImage); // Capture the decoder's state. If we need to notify asynchronously, it's // important that we don't wait until the lambda actually runs to capture the // state that we're going to notify. That would both introduce data races on // the decoder's state and cause inconsistencies between the NotifyProgress() // calls we make off-main-thread and the notifications that RasterImage // actually receives, which would cause bugs. Progress progress = aDecoder->TakeProgress(); UnorientedIntRect invalidRect = UnorientedIntRect::FromUnknownRect(aDecoder->TakeInvalidRect()); Maybe frameCount = aDecoder->TakeCompleteFrameCount(); DecoderFlags decoderFlags = aDecoder->GetDecoderFlags(); SurfaceFlags surfaceFlags = aDecoder->GetSurfaceFlags(); // Synchronously notify if we can. if (IsOnEventTarget() && !(decoderFlags & DecoderFlags::ASYNC_NOTIFY)) { aImage->NotifyProgress(progress, invalidRect, frameCount, decoderFlags, surfaceFlags); return; } // Don't try to dispatch after shutdown, we'll just leak the runnable. if (gXPCOMThreadsShutDown) { return; } // We're forced to notify asynchronously. NotNull> image = aImage; mEventTarget->Dispatch(CreateMediumHighRunnable(NS_NewRunnableFunction( "IDecodingTask::NotifyProgress", [=]() -> void { image->NotifyProgress(progress, invalidRect, frameCount, decoderFlags, surfaceFlags); })), NS_DISPATCH_NORMAL); } void IDecodingTask::NotifyDecodeComplete(NotNull aImage, NotNull aDecoder) { MOZ_ASSERT(aDecoder->HasError() || !aDecoder->InFrame(), "Decode complete in the middle of a frame?"); EnsureHasEventTarget(aImage); // Capture the decoder's state. DecoderFinalStatus finalStatus = aDecoder->FinalStatus(); ImageMetadata metadata = aDecoder->GetImageMetadata(); DecoderTelemetry telemetry = aDecoder->Telemetry(); Progress progress = aDecoder->TakeProgress(); UnorientedIntRect invalidRect = UnorientedIntRect::FromUnknownRect(aDecoder->TakeInvalidRect()); Maybe frameCount = aDecoder->TakeCompleteFrameCount(); DecoderFlags decoderFlags = aDecoder->GetDecoderFlags(); SurfaceFlags surfaceFlags = aDecoder->GetSurfaceFlags(); // Synchronously notify if we can. if (IsOnEventTarget() && !(decoderFlags & DecoderFlags::ASYNC_NOTIFY)) { aImage->NotifyDecodeComplete(finalStatus, metadata, telemetry, progress, invalidRect, frameCount, decoderFlags, surfaceFlags); return; } // Don't try to dispatch after shutdown, we'll just leak the runnable. if (gXPCOMThreadsShutDown) { return; } // We're forced to notify asynchronously. NotNull> image = aImage; mEventTarget->Dispatch(CreateMediumHighRunnable(NS_NewRunnableFunction( "IDecodingTask::NotifyDecodeComplete", [=]() -> void { image->NotifyDecodeComplete( finalStatus, metadata, telemetry, progress, invalidRect, frameCount, decoderFlags, surfaceFlags); })), NS_DISPATCH_NORMAL); } /////////////////////////////////////////////////////////////////////////////// // IDecodingTask implementation. /////////////////////////////////////////////////////////////////////////////// void IDecodingTask::Resume() { DecodePool::Singleton()->AsyncRun(this); } /////////////////////////////////////////////////////////////////////////////// // MetadataDecodingTask implementation. /////////////////////////////////////////////////////////////////////////////// MetadataDecodingTask::MetadataDecodingTask(NotNull aDecoder) : mMutex("mozilla::image::MetadataDecodingTask"), mDecoder(aDecoder) { MOZ_ASSERT(mDecoder->IsMetadataDecode(), "Use DecodingTask for non-metadata decodes"); } void MetadataDecodingTask::Run() { MutexAutoLock lock(mMutex); LexerResult result = mDecoder->Decode(WrapNotNull(this)); if (result.is()) { NotifyDecodeComplete(mDecoder->GetImage(), mDecoder); return; // We're done. } if (result == LexerResult(Yield::NEED_MORE_DATA)) { // We can't make any more progress right now. We also don't want to report // any progress, because it's important that metadata decode results are // delivered atomically. The decoder itself will ensure that we get // reenqueued when more data is available; just return for now. return; } MOZ_ASSERT_UNREACHABLE("Metadata decode yielded for an unexpected reason"); } /////////////////////////////////////////////////////////////////////////////// // AnonymousDecodingTask implementation. /////////////////////////////////////////////////////////////////////////////// AnonymousDecodingTask::AnonymousDecodingTask(NotNull aDecoder, bool aResumable) : mDecoder(aDecoder), mResumable(aResumable) {} void AnonymousDecodingTask::Run() { while (true) { LexerResult result = mDecoder->Decode(WrapNotNull(this)); if (result.is()) { return; // We're done. } if (result == LexerResult(Yield::NEED_MORE_DATA)) { // We can't make any more progress right now. Let the caller decide how to // handle it. return; } // Right now we don't do anything special for other kinds of yields, so just // keep working. MOZ_ASSERT(result.is()); } } void AnonymousDecodingTask::Resume() { // Anonymous decoders normally get all their data at once. We have tests // where they don't; typically in these situations, the test re-runs them // manually. However some tests want to verify Resume works, so they will // explicitly request this behaviour. if (mResumable) { RefPtr self(this); NS_DispatchToMainThread( NS_NewRunnableFunction("image::AnonymousDecodingTask::Resume", [self]() -> void { self->Run(); })); } } } // namespace image } // namespace mozilla