author Ryan VanderMeulen <>
Wed, 17 Jan 2018 15:55:38 -0500
changeset 399709 ef04f3ad847540c876c130b7d140a960d922a024
parent 391897 7159964287fe161b0dda9cdfa59d74bc7bead348
child 444021 5223058ac4fffd00aad34eeb29998c3264b250e8
permissions -rw-r--r--
Backed out 20 changesets (bug 1411654) for incorrect android:debuggable. r=nalexander, a=RyanVM Backed out changeset cfad693be918 (bug 1411654) Backed out changeset 55776829a744 (bug 1411654) Backed out changeset c5bf85d56fed (bug 1411654) Backed out changeset c270f97bb0da (bug 1411654) Backed out changeset fde9bf9c14c3 (bug 1411654) Backed out changeset 01836fd98c63 (bug 1411654) Backed out changeset 730a70767743 (bug 1411654) Backed out changeset 690e265c684c (bug 1411654) Backed out changeset f918500d9cf5 (bug 1411654) Backed out changeset cec2b8828cc8 (bug 1411654) Backed out changeset 76085ddd5ac7 (bug 1411654) Backed out changeset 2b37201606f5 (bug 1411654) Backed out changeset d0d513d1c379 (bug 1411654) Backed out changeset e7b0cc801cf1 (bug 1411654) Backed out changeset 901b304603d9 (bug 1411654) Backed out changeset 373c9a71d945 (bug 1411654) Backed out changeset 3dc3beab95f8 (bug 1411654) Backed out changeset 22a861db1573 (bug 1411654) Backed out changeset 0850b319efd4 (bug 1411654) Backed out changeset d276d3deba05 (bug 1411654)

/* -*- 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 */

 * An interface for tasks which can execute on the ImageLib DecodePool, and
 * various implementations.

#ifndef mozilla_image_IDecodingTask_h
#define mozilla_image_IDecodingTask_h

#include "imgFrame.h"
#include "mozilla/NotNull.h"
#include "mozilla/RefPtr.h"
#include "nsIEventTarget.h"
#include "SourceBuffer.h"

namespace mozilla {
namespace image {

class Decoder;
class RasterImage;

/// A priority hint that DecodePool can use when scheduling an IDecodingTask.
enum class TaskPriority : uint8_t

 * An interface for tasks which can execute on the ImageLib DecodePool.
class IDecodingTask : public IResumable
  /// Run the task.
  virtual void Run() = 0;

  /// @return true if, given the option, this task prefers to run synchronously.
  virtual bool ShouldPreferSyncRun() const = 0;

  /// @return a priority hint that DecodePool can use when scheduling this task.
  virtual TaskPriority Priority() const = 0;

  /// A default implementation of IResumable which resubmits the task to the
  /// DecodePool. Subclasses can override this if they need different behavior.
  void Resume() override;

  virtual ~IDecodingTask() { }

  /// Notify @aImage of @aDecoder's progress.
  void NotifyProgress(NotNull<RasterImage*> aImage,
                      NotNull<Decoder*> aDecoder);

  /// Notify @aImage that @aDecoder has finished.
  void NotifyDecodeComplete(NotNull<RasterImage*> aImage,
                            NotNull<Decoder*> aDecoder);

  void EnsureHasEventTarget(NotNull<RasterImage*> aImage);

  bool IsOnEventTarget() const;

  nsCOMPtr<nsIEventTarget> mEventTarget;

 * An IDecodingTask implementation for metadata decodes of images.
class MetadataDecodingTask final : public IDecodingTask

  explicit MetadataDecodingTask(NotNull<Decoder*> aDecoder);

  void Run() override;

  // Metadata decodes are very fast (since they only need to examine an image's
  // header) so there's no reason to refuse to run them synchronously if the
  // caller will allow us to.
  bool ShouldPreferSyncRun() const override { return true; }

  // Metadata decodes run at the highest priority because they block layout and
  // page load.
  TaskPriority Priority() const override { return TaskPriority::eHigh; }

  virtual ~MetadataDecodingTask() { }

  /// Mutex protecting access to mDecoder.
  Mutex mMutex;

  NotNull<RefPtr<Decoder>> mDecoder;

 * An IDecodingTask implementation for anonymous decoders - that is, decoders
 * with no associated Image object.
class AnonymousDecodingTask final : public IDecodingTask
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AnonymousDecodingTask, override)

  explicit AnonymousDecodingTask(NotNull<Decoder*> aDecoder);

  void Run() override;

  bool ShouldPreferSyncRun() const override { return true; }
  TaskPriority Priority() const override { return TaskPriority::eLow; }

  // Anonymous decoders normally get all their data at once. We have tests where
  // they don't; in these situations, the test re-runs them manually. So no
  // matter what, we don't want to resume by posting a task to the DecodePool.
  void Resume() override { }

  virtual ~AnonymousDecodingTask() { }

  NotNull<RefPtr<Decoder>> mDecoder;

} // namespace image
} // namespace mozilla

#endif // mozilla_image_IDecodingTask_h