Add m-esr52 at 52.6.0

1 files changed, 348 insertions, 0 deletions

diff --git a/dom/media/StreamTracks.h b/dom/media/StreamTracks.h
new file mode 100644
index 000000000..0152c3bae
--- /dev/null
+++ b/dom/media/StreamTracks.h
@@ -0,0 +1,348 @@
+/* -*- 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/. */
+
+#ifndef MOZILLA_STREAMTRACKS_H_
+#define MOZILLA_STREAMTRACKS_H_
+
+#include "MediaSegment.h"
+#include "nsAutoPtr.h"
+
+namespace mozilla {
+
+/**
+ * Unique ID for track within a StreamTracks. Tracks from different
+ * StreamTrackss may have the same ID; this matters when appending StreamTrackss,
+ * since tracks with the same ID are matched. Only IDs greater than 0 are allowed.
+ */
+typedef int32_t TrackID;
+const TrackID TRACK_NONE = 0;
+const TrackID TRACK_INVALID = -1;
+const TrackID TRACK_ANY = -2;
+
+inline bool IsTrackIDExplicit(const TrackID& aId) {
+  return aId > TRACK_NONE;
+}
+
+inline TrackTicks RateConvertTicksRoundDown(TrackRate aOutRate,
+                                            TrackRate aInRate,
+                                            TrackTicks aTicks)
+{
+  NS_ASSERTION(0 < aOutRate && aOutRate <= TRACK_RATE_MAX, "Bad out rate");
+  NS_ASSERTION(0 < aInRate && aInRate <= TRACK_RATE_MAX, "Bad in rate");
+  NS_ASSERTION(0 <= aTicks && aTicks <= TRACK_TICKS_MAX, "Bad ticks");
+  return (aTicks * aOutRate) / aInRate;
+}
+inline TrackTicks RateConvertTicksRoundUp(TrackRate aOutRate,
+                                          TrackRate aInRate, TrackTicks aTicks)
+{
+  NS_ASSERTION(0 < aOutRate && aOutRate <= TRACK_RATE_MAX, "Bad out rate");
+  NS_ASSERTION(0 < aInRate && aInRate <= TRACK_RATE_MAX, "Bad in rate");
+  NS_ASSERTION(0 <= aTicks && aTicks <= TRACK_TICKS_MAX, "Bad ticks");
+  return (aTicks * aOutRate + aInRate - 1) / aInRate;
+}
+
+/**
+ * This object contains the decoded data for a stream's tracks.
+ * A StreamTracks can be appended to. Logically a StreamTracks only gets longer,
+ * but we also have the ability to "forget" data before a certain time that
+ * we know won't be used again. (We prune a whole number of seconds internally.)
+ *
+ * StreamTrackss should only be used from one thread at a time.
+ *
+ * A StreamTracks has a set of tracks that can be of arbitrary types ---
+ * the data for each track is a MediaSegment. The set of tracks can vary
+ * over the timeline of the StreamTracks.
+ */
+class StreamTracks
+{
+public:
+  /**
+   * Every track has a start time --- when it started in the StreamTracks.
+   * It has an end flag; when false, no end point is known; when true,
+   * the track ends when the data we have for the track runs out.
+   * Tracks have a unique ID assigned at creation. This allows us to identify
+   * the same track across StreamTrackss. A StreamTracks should never have
+   * two tracks with the same ID (even if they don't overlap in time).
+   * TODO Tracks can also be enabled and disabled over time.
+   * Takes ownership of aSegment.
+   */
+  class Track final
+  {
+    Track(TrackID aID, StreamTime aStart, MediaSegment* aSegment)
+      : mStart(aStart),
+        mSegment(aSegment),
+        mID(aID),
+        mEnded(false)
+    {
+      MOZ_COUNT_CTOR(Track);
+
+      NS_ASSERTION(aID > TRACK_NONE, "Bad track ID");
+      NS_ASSERTION(0 <= aStart && aStart <= aSegment->GetDuration(), "Bad start position");
+    }
+
+  public:
+    ~Track()
+    {
+      MOZ_COUNT_DTOR(Track);
+    }
+
+    template <class T> T* Get() const
+    {
+      if (mSegment->GetType() == T::StaticType()) {
+        return static_cast<T*>(mSegment.get());
+      }
+      return nullptr;
+    }
+
+    MediaSegment* GetSegment() const { return mSegment; }
+    TrackID GetID() const { return mID; }
+    bool IsEnded() const { return mEnded; }
+    StreamTime GetStart() const { return mStart; }
+    StreamTime GetEnd() const { return mSegment->GetDuration(); }
+    MediaSegment::Type GetType() const { return mSegment->GetType(); }
+
+    void SetEnded() { mEnded = true; }
+    void AppendFrom(Track* aTrack)
+    {
+      NS_ASSERTION(!mEnded, "Can't append to ended track");
+      NS_ASSERTION(aTrack->mID == mID, "IDs must match");
+      NS_ASSERTION(aTrack->mStart == 0, "Source track must start at zero");
+      NS_ASSERTION(aTrack->mSegment->GetType() == GetType(), "Track types must match");
+
+      mSegment->AppendFrom(aTrack->mSegment);
+      mEnded = aTrack->mEnded;
+    }
+    MediaSegment* RemoveSegment()
+    {
+      return mSegment.forget();
+    }
+    void ForgetUpTo(StreamTime aTime)
+    {
+      mSegment->ForgetUpTo(aTime);
+    }
+    void FlushAfter(StreamTime aNewEnd)
+    {
+      // Forget everything after a given endpoint
+      // a specified amount
+      mSegment->FlushAfter(aNewEnd);
+    }
+
+    size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
+    {
+      size_t amount = aMallocSizeOf(this);
+      if (mSegment) {
+        amount += mSegment->SizeOfIncludingThis(aMallocSizeOf);
+      }
+      return amount;
+    }
+
+  private:
+    friend class StreamTracks;
+
+    // Start offset is in ticks at rate mRate
+    StreamTime mStart;
+    // The segment data starts at the start of the owning StreamTracks, i.e.,
+    // there's mStart silence/no video at the beginning.
+    nsAutoPtr<MediaSegment> mSegment;
+    // Unique ID
+    TrackID mID;
+    // True when the track ends with the data in mSegment
+    bool mEnded;
+  };
+
+  class MOZ_STACK_CLASS CompareTracksByID final
+  {
+  public:
+    bool Equals(Track* aA, Track* aB) const {
+      return aA->GetID() == aB->GetID();
+    }
+    bool LessThan(Track* aA, Track* aB) const {
+      return aA->GetID() < aB->GetID();
+    }
+  };
+
+  StreamTracks()
+    : mGraphRate(0)
+    , mTracksKnownTime(0)
+    , mForgottenTime(0)
+    , mTracksDirty(false)
+#ifdef DEBUG
+    , mGraphRateIsSet(false)
+#endif
+  {
+    MOZ_COUNT_CTOR(StreamTracks);
+  }
+  ~StreamTracks()
+  {
+    MOZ_COUNT_DTOR(StreamTracks);
+  }
+
+  size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
+  {
+    size_t amount = 0;
+    amount += mTracks.ShallowSizeOfExcludingThis(aMallocSizeOf);
+    for (size_t i = 0; i < mTracks.Length(); i++) {
+      amount += mTracks[i]->SizeOfIncludingThis(aMallocSizeOf);
+    }
+    return amount;
+  }
+
+  /**
+   * Initialize the graph rate for use in calculating StreamTimes from track
+   * ticks.  Called when a MediaStream's graph pointer is initialized.
+   */
+  void InitGraphRate(TrackRate aGraphRate)
+  {
+    mGraphRate = aGraphRate;
+#if DEBUG
+    MOZ_ASSERT(!mGraphRateIsSet);
+    mGraphRateIsSet = true;
+#endif
+  }
+
+  TrackRate GraphRate() const
+  {
+    MOZ_ASSERT(mGraphRateIsSet);
+    return mGraphRate;
+  }
+
+  /**
+   * Takes ownership of aSegment. Don't do this while iterating, or while
+   * holding a Track reference.
+   * aSegment must have aStart worth of null data.
+   */
+  Track& AddTrack(TrackID aID, StreamTime aStart, MediaSegment* aSegment)
+  {
+    NS_ASSERTION(!FindTrack(aID), "Track with this ID already exists");
+
+    Track* track = new Track(aID, aStart, aSegment);
+    mTracks.InsertElementSorted(track, CompareTracksByID());
+    mTracksDirty = true;
+
+    if (mTracksKnownTime == STREAM_TIME_MAX) {
+      // There exists code like
+      // http://mxr.mozilla.org/mozilla-central/source/media/webrtc/signaling/src/mediapipeline/MediaPipeline.cpp?rev=96b197deb91e&mark=1292-1297#1292
+      NS_WARNING("Adding track to StreamTracks that should have no more tracks");
+    } else {
+      NS_ASSERTION(mTracksKnownTime <= aStart, "Start time too early");
+    }
+    return *track;
+  }
+
+  void AdvanceKnownTracksTime(StreamTime aKnownTime)
+  {
+    NS_ASSERTION(aKnownTime >= mTracksKnownTime, "Can't move tracks-known time earlier");
+    mTracksKnownTime = aKnownTime;
+  }
+
+  /**
+   * The end time for the StreamTracks is the latest time for which we have
+   * data for all tracks that haven't ended by that time.
+   */
+  StreamTime GetEnd() const;
+
+  /**
+   * Returns the earliest time >= 0 at which all tracks have ended
+   * and all their data has been played out and no new tracks can be added,
+   * or STREAM_TIME_MAX if there is no such time.
+   */
+  StreamTime GetAllTracksEnd() const;
+
+#ifdef DEBUG
+  void DumpTrackInfo() const;
+#endif
+
+  Track* FindTrack(TrackID aID);
+
+  class MOZ_STACK_CLASS TrackIter final
+  {
+  public:
+    /**
+     * Iterate through the tracks of aBuffer in order of ID.
+     */
+    explicit TrackIter(const StreamTracks& aBuffer) :
+      mBuffer(&aBuffer.mTracks), mIndex(0), mMatchType(false) {}
+    /**
+     * Iterate through the tracks of aBuffer with type aType, in order of ID.
+     */
+    TrackIter(const StreamTracks& aBuffer, MediaSegment::Type aType) :
+      mBuffer(&aBuffer.mTracks), mIndex(0), mType(aType), mMatchType(true) { FindMatch(); }
+    bool IsEnded() { return mIndex >= mBuffer->Length(); }
+    void Next()
+    {
+      ++mIndex;
+      FindMatch();
+    }
+    Track* get() { return mBuffer->ElementAt(mIndex); }
+    Track& operator*() { return *mBuffer->ElementAt(mIndex); }
+    Track* operator->() { return mBuffer->ElementAt(mIndex); }
+  private:
+    void FindMatch()
+    {
+      if (!mMatchType)
+        return;
+      while (mIndex < mBuffer->Length() &&
+             mBuffer->ElementAt(mIndex)->GetType() != mType) {
+        ++mIndex;
+      }
+    }
+
+    const nsTArray<nsAutoPtr<Track> >* mBuffer;
+    uint32_t mIndex;
+    MediaSegment::Type mType;
+    bool mMatchType;
+  };
+  friend class TrackIter;
+
+  /**
+   * Forget stream data before aTime; they will no longer be needed.
+   * Also can forget entire tracks that have ended at or before aTime.
+   * Can't be used to forget beyond GetEnd().
+   */
+  void ForgetUpTo(StreamTime aTime);
+  /**
+   * Clears out all Tracks and the data they are holding.
+   * MediaStreamGraph calls this during forced shutdown.
+   */
+  void Clear();
+  /**
+   * Returns the latest time passed to ForgetUpTo.
+   */
+  StreamTime GetForgottenDuration()
+  {
+    return mForgottenTime;
+  }
+
+  bool GetAndResetTracksDirty()
+  {
+    if (!mTracksDirty) {
+      return false;
+    }
+
+    mTracksDirty = false;
+    return true;
+  }
+
+protected:
+  TrackRate mGraphRate; // StreamTime per second
+  // Any new tracks added will start at or after this time. In other words, the track
+  // list is complete and correct for all times less than this time.
+  StreamTime mTracksKnownTime;
+  StreamTime mForgottenTime;
+
+private:
+  // All known tracks for this StreamTracks
+  nsTArray<nsAutoPtr<Track>> mTracks;
+  bool mTracksDirty;
+
+#ifdef DEBUG
+  bool mGraphRateIsSet;
+#endif
+};
+
+} // namespace mozilla
+
+#endif /* MOZILLA_STREAMTRACKS_H_ */
+