1 files changed, 470 insertions, 0 deletions
diff --git a/dom/media/AccurateSeekTask.cpp b/dom/media/AccurateSeekTask.cpp
new file mode 100644
index 000000000..30eeb5904
--- /dev/null
+++ b/dom/media/AccurateSeekTask.cpp
@@ -0,0 +1,470 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "AccurateSeekTask.h"
+#include "MediaDecoderReaderWrapper.h"
+#include "mozilla/AbstractThread.h"
+#include "mozilla/Assertions.h"
+#include "nsPrintfCString.h"
+
+namespace mozilla {
+
+extern LazyLogModule gMediaDecoderLog;
+extern LazyLogModule gMediaSampleLog;
+
+// avoid redefined macro in unified build
+#undef FMT
+#undef DECODER_LOG
+#undef SAMPLE_LOG
+#undef DECODER_WARN
+
+#define FMT(x, ...) "[AccurateSeekTask] Decoder=%p " x, mDecoderID, ##__VA_ARGS__
+#define DECODER_LOG(...) MOZ_LOG(gMediaDecoderLog, LogLevel::Debug,   (FMT(__VA_ARGS__)))
+#define SAMPLE_LOG(...)  MOZ_LOG(gMediaSampleLog,  LogLevel::Debug,   (FMT(__VA_ARGS__)))
+#define DECODER_WARN(...) NS_WARNING(nsPrintfCString(FMT(__VA_ARGS__)).get())
+
+AccurateSeekTask::AccurateSeekTask(const void* aDecoderID,
+                                   AbstractThread* aThread,
+                                   MediaDecoderReaderWrapper* aReader,
+                                   const SeekTarget& aTarget,
+                                   const MediaInfo& aInfo,
+                                   const media::TimeUnit& aEnd,
+                                   int64_t aCurrentMediaTime)
+  : SeekTask(aDecoderID, aThread, aReader, aTarget)
+  , mCurrentTimeBeforeSeek(media::TimeUnit::FromMicroseconds(aCurrentMediaTime))
+  , mAudioRate(aInfo.mAudio.mRate)
+  , mDoneAudioSeeking(!aInfo.HasAudio() || aTarget.IsVideoOnly())
+  , mDoneVideoSeeking(!aInfo.HasVideo())
+{
+  AssertOwnerThread();
+
+  // Bound the seek time to be inside the media range.
+  NS_ASSERTION(aEnd.ToMicroseconds() != -1, "Should know end time by now");
+  mTarget.SetTime(std::max(media::TimeUnit(), std::min(mTarget.GetTime(), aEnd)));
+
+  // Configure MediaDecoderReaderWrapper.
+  SetCallbacks();
+}
+
+AccurateSeekTask::~AccurateSeekTask()
+{
+  AssertOwnerThread();
+  MOZ_ASSERT(mIsDiscarded);
+}
+
+void
+AccurateSeekTask::Discard()
+{
+  AssertOwnerThread();
+
+  // Disconnect MDSM.
+  RejectIfExist(NS_ERROR_DOM_MEDIA_CANCELED, __func__);
+
+  // Disconnect MediaDecoderReaderWrapper.
+  mSeekRequest.DisconnectIfExists();
+  CancelCallbacks();
+
+  mIsDiscarded = true;
+}
+
+bool
+AccurateSeekTask::NeedToResetMDSM() const
+{
+  AssertOwnerThread();
+  return true;
+}
+
+RefPtr<AccurateSeekTask::SeekTaskPromise>
+AccurateSeekTask::Seek(const media::TimeUnit& aDuration)
+{
+  AssertOwnerThread();
+
+  // Do the seek.
+  mSeekRequest.Begin(mReader->Seek(mTarget, aDuration)
+    ->Then(OwnerThread(), __func__, this,
+           &AccurateSeekTask::OnSeekResolved, &AccurateSeekTask::OnSeekRejected));
+
+  return mSeekTaskPromise.Ensure(__func__);
+}
+
+void
+AccurateSeekTask::RequestAudioData()
+{
+  AssertOwnerThread();
+  MOZ_ASSERT(!mDoneAudioSeeking);
+  MOZ_ASSERT(!mReader->IsRequestingAudioData());
+  MOZ_ASSERT(!mReader->IsWaitingAudioData());
+  mReader->RequestAudioData();
+}
+
+void
+AccurateSeekTask::RequestVideoData()
+{
+  AssertOwnerThread();
+  MOZ_ASSERT(!mDoneVideoSeeking);
+  MOZ_ASSERT(!mReader->IsRequestingVideoData());
+  MOZ_ASSERT(!mReader->IsWaitingVideoData());
+  mReader->RequestVideoData(false, media::TimeUnit());
+}
+
+nsresult
+AccurateSeekTask::DropAudioUpToSeekTarget(MediaData* aSample)
+{
+  AssertOwnerThread();
+
+  RefPtr<AudioData> audio(aSample->As<AudioData>());
+  MOZ_ASSERT(audio && mTarget.IsAccurate());
+
+  CheckedInt64 sampleDuration = FramesToUsecs(audio->mFrames, mAudioRate);
+  if (!sampleDuration.isValid()) {
+    return NS_ERROR_DOM_MEDIA_OVERFLOW_ERR;
+  }
+
+  if (audio->mTime + sampleDuration.value() <= mTarget.GetTime().ToMicroseconds()) {
+    // Our seek target lies after the frames in this AudioData. Don't
+    // push it onto the audio queue, and keep decoding forwards.
+    return NS_OK;
+  }
+
+  if (audio->mTime > mTarget.GetTime().ToMicroseconds()) {
+    // The seek target doesn't lie in the audio block just after the last
+    // audio frames we've seen which were before the seek target. This
+    // could have been the first audio data we've seen after seek, i.e. the
+    // seek terminated after the seek target in the audio stream. Just
+    // abort the audio decode-to-target, the state machine will play
+    // silence to cover the gap. Typically this happens in poorly muxed
+    // files.
+    DECODER_WARN("Audio not synced after seek, maybe a poorly muxed file?");
+    mSeekedAudioData = audio;
+    mDoneAudioSeeking = true;
+    return NS_OK;
+  }
+
+  // The seek target lies somewhere in this AudioData's frames, strip off
+  // any frames which lie before the seek target, so we'll begin playback
+  // exactly at the seek target.
+  NS_ASSERTION(mTarget.GetTime().ToMicroseconds() >= audio->mTime,
+               "Target must at or be after data start.");
+  NS_ASSERTION(mTarget.GetTime().ToMicroseconds() < audio->mTime + sampleDuration.value(),
+               "Data must end after target.");
+
+  CheckedInt64 framesToPrune =
+    UsecsToFrames(mTarget.GetTime().ToMicroseconds() - audio->mTime, mAudioRate);
+  if (!framesToPrune.isValid()) {
+    return NS_ERROR_DOM_MEDIA_OVERFLOW_ERR;
+  }
+  if (framesToPrune.value() > audio->mFrames) {
+    // We've messed up somehow. Don't try to trim frames, the |frames|
+    // variable below will overflow.
+    DECODER_WARN("Can't prune more frames that we have!");
+    return NS_ERROR_FAILURE;
+  }
+  uint32_t frames = audio->mFrames - static_cast<uint32_t>(framesToPrune.value());
+  uint32_t channels = audio->mChannels;
+  AlignedAudioBuffer audioData(frames * channels);
+  if (!audioData) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  memcpy(audioData.get(),
+         audio->mAudioData.get() + (framesToPrune.value() * channels),
+         frames * channels * sizeof(AudioDataValue));
+  CheckedInt64 duration = FramesToUsecs(frames, mAudioRate);
+  if (!duration.isValid()) {
+    return NS_ERROR_DOM_MEDIA_OVERFLOW_ERR;
+  }
+  RefPtr<AudioData> data(new AudioData(audio->mOffset,
+                                       mTarget.GetTime().ToMicroseconds(),
+                                       duration.value(),
+                                       frames,
+                                       Move(audioData),
+                                       channels,
+                                       audio->mRate));
+  MOZ_ASSERT(!mSeekedAudioData, "Should be the 1st sample after seeking");
+  mSeekedAudioData = data;
+  mDoneAudioSeeking = true;
+
+  return NS_OK;
+}
+
+nsresult
+AccurateSeekTask::DropVideoUpToSeekTarget(MediaData* aSample)
+{
+  AssertOwnerThread();
+
+  RefPtr<VideoData> video(aSample->As<VideoData>());
+  MOZ_ASSERT(video);
+  DECODER_LOG("DropVideoUpToSeekTarget() frame [%lld, %lld]",
+              video->mTime, video->GetEndTime());
+  const int64_t target = mTarget.GetTime().ToMicroseconds();
+
+  // If the frame end time is less than the seek target, we won't want
+  // to display this frame after the seek, so discard it.
+  if (target >= video->GetEndTime()) {
+    DECODER_LOG("DropVideoUpToSeekTarget() pop video frame [%lld, %lld] target=%lld",
+                video->mTime, video->GetEndTime(), target);
+    mFirstVideoFrameAfterSeek = video;
+  } else {
+    if (target >= video->mTime && video->GetEndTime() >= target) {
+      // The seek target lies inside this frame's time slice. Adjust the frame's
+      // start time to match the seek target. We do this by replacing the
+      // first frame with a shallow copy which has the new timestamp.
+      RefPtr<VideoData> temp = VideoData::ShallowCopyUpdateTimestamp(video.get(), target);
+      video = temp;
+    }
+    mFirstVideoFrameAfterSeek = nullptr;
+
+    DECODER_LOG("DropVideoUpToSeekTarget() found video frame [%lld, %lld] containing target=%lld",
+                video->mTime, video->GetEndTime(), target);
+
+    MOZ_ASSERT(!mSeekedVideoData, "Should be the 1st sample after seeking");
+    mSeekedVideoData = video;
+    mDoneVideoSeeking = true;
+  }
+
+  return NS_OK;
+}
+
+void
+AccurateSeekTask::MaybeFinishSeek()
+{
+  AssertOwnerThread();
+  if (mDoneAudioSeeking && mDoneVideoSeeking) {
+    Resolve(__func__); // Call to MDSM::SeekCompleted();
+  }
+}
+
+void
+AccurateSeekTask::OnSeekResolved(media::TimeUnit)
+{
+  AssertOwnerThread();
+
+  mSeekRequest.Complete();
+  // We must decode the first samples of active streams, so we can determine
+  // the new stream time. So dispatch tasks to do that.
+  if (!mDoneVideoSeeking) {
+    RequestVideoData();
+  }
+  if (!mDoneAudioSeeking) {
+    RequestAudioData();
+  }
+}
+
+void
+AccurateSeekTask::OnSeekRejected(nsresult aResult)
+{
+  AssertOwnerThread();
+
+  mSeekRequest.Complete();
+  MOZ_ASSERT(NS_FAILED(aResult), "Cancels should also disconnect mSeekRequest");
+  RejectIfExist(aResult, __func__);
+}
+
+void
+AccurateSeekTask::AdjustFastSeekIfNeeded(MediaData* aSample)
+{
+  AssertOwnerThread();
+  if (mTarget.IsFast() &&
+      mTarget.GetTime() > mCurrentTimeBeforeSeek &&
+      aSample->mTime < mCurrentTimeBeforeSeek.ToMicroseconds()) {
+    // We are doing a fastSeek, but we ended up *before* the previous
+    // playback position. This is surprising UX, so switch to an accurate
+    // seek and decode to the seek target. This is not conformant to the
+    // spec, fastSeek should always be fast, but until we get the time to
+    // change all Readers to seek to the keyframe after the currentTime
+    // in this case, we'll just decode forward. Bug 1026330.
+    mTarget.SetType(SeekTarget::Accurate);
+  }
+}
+
+void
+AccurateSeekTask::OnAudioDecoded(MediaData* aAudioSample)
+{
+  AssertOwnerThread();
+  MOZ_ASSERT(!mSeekTaskPromise.IsEmpty(), "Seek shouldn't be finished");
+
+  RefPtr<MediaData> audio(aAudioSample);
+  MOZ_ASSERT(audio);
+
+  // The MDSM::mDecodedAudioEndTime will be updated once the whole SeekTask is
+  // resolved.
+
+  SAMPLE_LOG("OnAudioDecoded [%lld,%lld]", audio->mTime, audio->GetEndTime());
+
+  // Video-only seek doesn't reset audio decoder. There might be pending audio
+  // requests when AccurateSeekTask::Seek() begins. We will just store the data
+  // without checking |mDiscontinuity| or calling DropAudioUpToSeekTarget().
+  if (mTarget.IsVideoOnly()) {
+    mSeekedAudioData = audio.forget();
+    return;
+  }
+
+  AdjustFastSeekIfNeeded(audio);
+
+  if (mTarget.IsFast()) {
+    // Non-precise seek; we can stop the seek at the first sample.
+    mSeekedAudioData = audio;
+    mDoneAudioSeeking = true;
+  } else {
+    nsresult rv = DropAudioUpToSeekTarget(audio);
+    if (NS_FAILED(rv)) {
+      CancelCallbacks();
+      RejectIfExist(rv, __func__);
+      return;
+    }
+  }
+
+  if (!mDoneAudioSeeking) {
+    RequestAudioData();
+    return;
+  }
+  MaybeFinishSeek();
+}
+
+void
+AccurateSeekTask::OnNotDecoded(MediaData::Type aType,
+                               const MediaResult& aError)
+{
+  AssertOwnerThread();
+  MOZ_ASSERT(!mSeekTaskPromise.IsEmpty(), "Seek shouldn't be finished");
+
+  SAMPLE_LOG("OnNotDecoded type=%d reason=%u", aType, aError.Code());
+
+  // Ignore pending requests from video-only seek.
+  if (aType == MediaData::AUDIO_DATA && mTarget.IsVideoOnly()) {
+    return;
+  }
+
+  // If the decoder is waiting for data, we tell it to call us back when the
+  // data arrives.
+  if (aError == NS_ERROR_DOM_MEDIA_WAITING_FOR_DATA) {
+    mReader->WaitForData(aType);
+    return;
+  }
+
+  if (aError == NS_ERROR_DOM_MEDIA_CANCELED) {
+    if (aType == MediaData::AUDIO_DATA) {
+      RequestAudioData();
+    } else {
+      RequestVideoData();
+    }
+    return;
+  }
+
+  if (aError == NS_ERROR_DOM_MEDIA_END_OF_STREAM) {
+    if (aType == MediaData::AUDIO_DATA) {
+      mIsAudioQueueFinished = true;
+      mDoneAudioSeeking = true;
+    } else {
+      mIsVideoQueueFinished = true;
+      mDoneVideoSeeking = true;
+      if (mFirstVideoFrameAfterSeek) {
+        // Hit the end of stream. Move mFirstVideoFrameAfterSeek into
+        // mSeekedVideoData so we have something to display after seeking.
+        mSeekedVideoData = mFirstVideoFrameAfterSeek.forget();
+      }
+    }
+    MaybeFinishSeek();
+    return;
+  }
+
+  // This is a decode error, delegate to the generic error path.
+  CancelCallbacks();
+  RejectIfExist(aError, __func__);
+}
+
+void
+AccurateSeekTask::OnVideoDecoded(MediaData* aVideoSample)
+{
+  AssertOwnerThread();
+  MOZ_ASSERT(!mSeekTaskPromise.IsEmpty(), "Seek shouldn't be finished");
+
+  RefPtr<MediaData> video(aVideoSample);
+  MOZ_ASSERT(video);
+
+  // The MDSM::mDecodedVideoEndTime will be updated once the whole SeekTask is
+  // resolved.
+
+  SAMPLE_LOG("OnVideoDecoded [%lld,%lld]", video->mTime, video->GetEndTime());
+
+  AdjustFastSeekIfNeeded(video);
+
+  if (mTarget.IsFast()) {
+    // Non-precise seek. We can stop the seek at the first sample.
+    mSeekedVideoData = video;
+    mDoneVideoSeeking = true;
+  } else {
+    nsresult rv = DropVideoUpToSeekTarget(video.get());
+    if (NS_FAILED(rv)) {
+      CancelCallbacks();
+      RejectIfExist(rv, __func__);
+      return;
+    }
+  }
+
+  if (!mDoneVideoSeeking) {
+    RequestVideoData();
+    return;
+  }
+  MaybeFinishSeek();
+}
+
+void
+AccurateSeekTask::SetCallbacks()
+{
+  AssertOwnerThread();
+
+  RefPtr<AccurateSeekTask> self = this;
+  mAudioCallback = mReader->AudioCallback().Connect(
+    OwnerThread(), [self] (AudioCallbackData aData) {
+    if (aData.is<MediaData*>()) {
+      self->OnAudioDecoded(aData.as<MediaData*>());
+    } else {
+      self->OnNotDecoded(MediaData::AUDIO_DATA,
+        aData.as<MediaResult>());
+    }
+  });
+
+  mVideoCallback = mReader->VideoCallback().Connect(
+    OwnerThread(), [self] (VideoCallbackData aData) {
+    typedef Tuple<MediaData*, TimeStamp> Type;
+    if (aData.is<Type>()) {
+      self->OnVideoDecoded(Get<0>(aData.as<Type>()));
+    } else {
+      self->OnNotDecoded(MediaData::VIDEO_DATA,
+        aData.as<MediaResult>());
+    }
+  });
+
+  mAudioWaitCallback = mReader->AudioWaitCallback().Connect(
+    OwnerThread(), [self] (WaitCallbackData aData) {
+    // Ignore pending requests from video-only seek.
+    if (self->mTarget.IsVideoOnly()) {
+      return;
+    }
+    if (aData.is<MediaData::Type>()) {
+      self->RequestAudioData();
+    }
+  });
+
+  mVideoWaitCallback = mReader->VideoWaitCallback().Connect(
+    OwnerThread(), [self] (WaitCallbackData aData) {
+    if (aData.is<MediaData::Type>()) {
+      self->RequestVideoData();
+    }
+  });
+}
+
+void
+AccurateSeekTask::CancelCallbacks()
+{
+  AssertOwnerThread();
+  mAudioCallback.DisconnectIfExists();
+  mVideoCallback.DisconnectIfExists();
+  mAudioWaitCallback.DisconnectIfExists();
+  mVideoWaitCallback.DisconnectIfExists();
+}
+} // namespace mozilla