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Diffstat (limited to 'image/IDecodingTask.cpp')
| -rw-r--r-- | image/IDecodingTask.cpp | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/image/IDecodingTask.cpp b/image/IDecodingTask.cpp new file mode 100644 index 0000000000..a067e7a7d1 --- /dev/null +++ b/image/IDecodingTask.cpp @@ -0,0 +1,172 @@ +/* -*- 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 "gfxPrefs.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. +/////////////////////////////////////////////////////////////////////////////// + +/* static */ void +IDecodingTask::NotifyProgress(NotNull<RasterImage*> aImage, + NotNull<Decoder*> aDecoder) +{ + MOZ_ASSERT(aDecoder->HasProgress() && !aDecoder->IsMetadataDecode()); + + // 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(); + IntRect invalidRect = aDecoder->TakeInvalidRect(); + Maybe<uint32_t> frameCount = aDecoder->TakeCompleteFrameCount(); + DecoderFlags decoderFlags = aDecoder->GetDecoderFlags(); + SurfaceFlags surfaceFlags = aDecoder->GetSurfaceFlags(); + + // Synchronously notify if we can. + if (NS_IsMainThread() && !(decoderFlags & DecoderFlags::ASYNC_NOTIFY)) { + aImage->NotifyProgress(progress, invalidRect, frameCount, + decoderFlags, surfaceFlags); + return; + } + + // We're forced to notify asynchronously. + NotNull<RefPtr<RasterImage>> image = aImage; + NS_DispatchToMainThread(NS_NewRunnableFunction([=]() -> void { + image->NotifyProgress(progress, invalidRect, frameCount, + decoderFlags, surfaceFlags); + })); +} + +/* static */ void +IDecodingTask::NotifyDecodeComplete(NotNull<RasterImage*> aImage, + NotNull<Decoder*> aDecoder) +{ + MOZ_ASSERT(aDecoder->HasError() || !aDecoder->InFrame(), + "Decode complete in the middle of a frame?"); + + // Capture the decoder's state. + DecoderFinalStatus finalStatus = aDecoder->FinalStatus(); + ImageMetadata metadata = aDecoder->GetImageMetadata(); + DecoderTelemetry telemetry = aDecoder->Telemetry(); + Progress progress = aDecoder->TakeProgress(); + IntRect invalidRect = aDecoder->TakeInvalidRect(); + Maybe<uint32_t> frameCount = aDecoder->TakeCompleteFrameCount(); + DecoderFlags decoderFlags = aDecoder->GetDecoderFlags(); + SurfaceFlags surfaceFlags = aDecoder->GetSurfaceFlags(); + + // Synchronously notify if we can. + if (NS_IsMainThread() && !(decoderFlags & DecoderFlags::ASYNC_NOTIFY)) { + aImage->NotifyDecodeComplete(finalStatus, metadata, telemetry, progress, + invalidRect, frameCount, decoderFlags, + surfaceFlags); + return; + } + + // We're forced to notify asynchronously. + NotNull<RefPtr<RasterImage>> image = aImage; + NS_DispatchToMainThread(NS_NewRunnableFunction([=]() -> void { + image->NotifyDecodeComplete(finalStatus, metadata, telemetry, progress, + invalidRect, frameCount, decoderFlags, + surfaceFlags); + })); +} + + +/////////////////////////////////////////////////////////////////////////////// +// IDecodingTask implementation. +/////////////////////////////////////////////////////////////////////////////// + +void +IDecodingTask::Resume() +{ + DecodePool::Singleton()->AsyncRun(this); +} + + +/////////////////////////////////////////////////////////////////////////////// +// MetadataDecodingTask implementation. +/////////////////////////////////////////////////////////////////////////////// + +MetadataDecodingTask::MetadataDecodingTask(NotNull<Decoder*> 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<TerminalState>()) { + 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<Decoder*> aDecoder) + : mDecoder(aDecoder) +{ } + +void +AnonymousDecodingTask::Run() +{ + while (true) { + LexerResult result = mDecoder->Decode(WrapNotNull(this)); + + if (result.is<TerminalState>()) { + 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<Yield>()); + } +} + +} // namespace image +} // namespace mozilla |