1 files changed, 169 insertions, 0 deletions
diff --git a/dom/media/ChannelMediaDecoder.h b/dom/media/ChannelMediaDecoder.h
new file mode 100644
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--- /dev/null
+++ b/dom/media/ChannelMediaDecoder.h
@@ -0,0 +1,169 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef ChannelMediaDecoder_h_
+#define ChannelMediaDecoder_h_
+
+#include "MediaDecoder.h"
+#include "MediaResourceCallback.h"
+#include "MediaChannelStatistics.h"
+
+class nsIChannel;
+class nsIStreamListener;
+
+namespace mozilla {
+
+class BaseMediaResource;
+
+DDLoggedTypeDeclNameAndBase(ChannelMediaDecoder, MediaDecoder);
+
+class ChannelMediaDecoder
+    : public MediaDecoder,
+      public DecoderDoctorLifeLogger<ChannelMediaDecoder> {
+  // Used to register with MediaResource to receive notifications which will
+  // be forwarded to MediaDecoder.
+  class ResourceCallback : public MediaResourceCallback {
+    // Throttle calls to MediaDecoder::NotifyDataArrived()
+    // to be at most once per 500ms.
+    static const uint32_t sDelay = 500;
+
+   public:
+    explicit ResourceCallback(AbstractThread* aMainThread);
+    // Start to receive notifications from ResourceCallback.
+    void Connect(ChannelMediaDecoder* aDecoder);
+    // Called upon shutdown to stop receiving notifications.
+    void Disconnect();
+
+   private:
+    ~ResourceCallback();
+
+    /* MediaResourceCallback functions */
+    AbstractThread* AbstractMainThread() const override;
+    MediaDecoderOwner* GetMediaOwner() const override;
+    void NotifyNetworkError(const MediaResult& aError) override;
+    void NotifyDataArrived() override;
+    void NotifyDataEnded(nsresult aStatus) override;
+    void NotifyPrincipalChanged() override;
+    void NotifySuspendedStatusChanged(bool aSuspendedByCache) override;
+
+    static void TimerCallback(nsITimer* aTimer, void* aClosure);
+
+    // The decoder to send notifications. Main-thread only.
+    ChannelMediaDecoder* mDecoder = nullptr;
+    nsCOMPtr<nsITimer> mTimer;
+    bool mTimerArmed = false;
+    const RefPtr<AbstractThread> mAbstractMainThread;
+  };
+
+ protected:
+  void ShutdownInternal() override;
+  void OnPlaybackEvent(MediaPlaybackEvent&& aEvent) override;
+  void DurationChanged() override;
+  void MetadataLoaded(UniquePtr<MediaInfo> aInfo, UniquePtr<MetadataTags> aTags,
+                      MediaDecoderEventVisibility aEventVisibility) override;
+  void NotifyPrincipalChanged() override;
+
+  RefPtr<ResourceCallback> mResourceCallback;
+  RefPtr<BaseMediaResource> mResource;
+
+  explicit ChannelMediaDecoder(MediaDecoderInit& aInit);
+
+  void GetDebugInfo(dom::MediaDecoderDebugInfo& aInfo);
+
+ public:
+  // Create a decoder for the given aType. Returns null if we were unable
+  // to create the decoder, for example because the requested MIME type in
+  // the init struct was unsupported.
+  static already_AddRefed<ChannelMediaDecoder> Create(
+      MediaDecoderInit& aInit, DecoderDoctorDiagnostics* aDiagnostics);
+
+  void Shutdown() override;
+
+  bool CanClone();
+
+  // Create a new decoder of the same type as this one.
+  already_AddRefed<ChannelMediaDecoder> Clone(MediaDecoderInit& aInit);
+
+  nsresult Load(nsIChannel* aChannel, bool aIsPrivateBrowsing,
+                nsIStreamListener** aStreamListener);
+
+  void AddSizeOfResources(ResourceSizes* aSizes) override;
+  already_AddRefed<nsIPrincipal> GetCurrentPrincipal() override;
+  bool HadCrossOriginRedirects() override;
+  bool IsTransportSeekable() override;
+  void SetLoadInBackground(bool aLoadInBackground) override;
+  void Suspend() override;
+  void Resume() override;
+
+ private:
+  void DownloadProgressed();
+
+  // Create a new state machine to run this decoder.
+  MediaDecoderStateMachineBase* CreateStateMachine(
+      bool aDisableExternalEngine) override;
+
+  nsresult Load(BaseMediaResource* aOriginal);
+
+  // Called by MediaResource when the download has ended.
+  // Called on the main thread only. aStatus is the result from OnStopRequest.
+  void NotifyDownloadEnded(nsresult aStatus);
+
+  // Called by the MediaResource to keep track of the number of bytes read
+  // from the resource. Called on the main by an event runner dispatched
+  // by the MediaResource read functions.
+  void NotifyBytesConsumed(int64_t aBytes, int64_t aOffset);
+
+  bool CanPlayThroughImpl() final;
+
+  struct PlaybackRateInfo {
+    uint32_t mRate;  // Estimate of the current playback rate (bytes/second).
+    bool mReliable;  // True if mRate is a reliable estimate.
+  };
+  // The actual playback rate computation.
+  static PlaybackRateInfo ComputePlaybackRate(
+      const MediaChannelStatistics& aStats, BaseMediaResource* aResource,
+      double aDuration);
+
+  // Something has changed that could affect the computed playback rate,
+  // so recompute it.
+  static void UpdatePlaybackRate(const PlaybackRateInfo& aInfo,
+                                 BaseMediaResource* aResource);
+
+  // Return statistics. This is used for progress events and other things.
+  // This can be called from any thread. It's only a snapshot of the
+  // current state, since other threads might be changing the state
+  // at any time.
+  static MediaStatistics GetStatistics(const PlaybackRateInfo& aInfo,
+                                       BaseMediaResource* aRes,
+                                       int64_t aPlaybackPosition);
+
+  bool ShouldThrottleDownload(const MediaStatistics& aStats);
+
+  // Data needed to estimate playback data rate. The timeline used for
+  // this estimate is "decode time" (where the "current time" is the
+  // time of the last decoded video frame).
+  MediaChannelStatistics mPlaybackStatistics;
+
+  // Current playback position in the stream. This is (approximately)
+  // where we're up to playing back the stream. This is not adjusted
+  // during decoder seek operations, but it's updated at the end when we
+  // start playing back again.
+  int64_t mPlaybackPosition = 0;
+
+  bool mCanPlayThrough = false;
+
+  // True if we've been notified that the ChannelMediaResource has
+  // a principal.
+  bool mInitialChannelPrincipalKnown = false;
+
+  // Set in Shutdown() when we start closing mResource, if mResource is set.
+  // Must resolve before we unregister the shutdown blocker.
+  RefPtr<GenericPromise> mResourceClosePromise;
+};
+
+}  // namespace mozilla
+
+#endif  // ChannelMediaDecoder_h_