Enable seek in fullscreen mode for MSE impl on android

media/base/android/media_source_player.cc

Index: media/base/android/media_source_player.cc
diff --git a/media/base/android/media_source_player.cc b/media/base/android/media_source_player.cc
index b29d182d84938638a33561467efe1f6dae3f4c9a..9d47292c539b2a9e6400baab71ed32ba5a96d4c7 100644
--- a/media/base/android/media_source_player.cc
+++ b/media/base/android/media_source_player.cc
@@ -193,6 +193,8 @@ MediaSourcePlayer::MediaSourcePlayer(
     MediaPlayerManager* manager)
     : MediaPlayerAndroid(player_id, manager),
       pending_play_(false),
+      pending_media_seek_request_(false),
+      active_decoding_tasks_(0),
       width_(0),
       height_(0),
       audio_codec_(kUnknownAudioCodec),
@@ -271,7 +273,6 @@ int MediaSourcePlayer::GetVideoHeight() {
 void MediaSourcePlayer::SeekTo(base::TimeDelta timestamp) {
   last_presentation_timestamp_ = timestamp;
   start_wallclock_time_ = base::Time();
-  last_seek_time_ = base::Time::Now();
   if (audio_decoder_job_)
     audio_decoder_job_->Flush();
   if (video_decoder_job_)
@@ -280,7 +281,9 @@ void MediaSourcePlayer::SeekTo(base::TimeDelta timestamp) {
   received_video_ = MediaPlayerHostMsg_ReadFromDemuxerAck_Params();
   audio_access_unit_index_ = 0;
   video_access_unit_index_ = 0;
-  OnSeekComplete();
+  pending_media_seek_request_ = true;
+  if (!active_decoding_tasks_)

[ycheo (away), 2013/05/22 06:59:13]

This SeekTo() can be called from ContentVideoView::SeekTo() which is Java
thread.
So do we need a lock for the data members used in this method?

[qinmin, 2013/05/22 07:20:38]

SeekTo() is always called on the browser thread since the java view lives on it.
So there is no race condition here.
If you take a look at the MediaPlayerBridge, only the listener callbacks will be
on different threads. In that case, we always post the tasks onto the browser
thread.  Similarly for MediaSourcePlayer, all the calls should be on the browser
thread (excluding decoder jobs which has its own thread).

On 2013/05/22 06:59:13, Yuncheol Heo wrote:

+    manager()->OnMediaSeekRequest(player_id(), last_presentation_timestamp_);
 }
 
 base::TimeDelta MediaSourcePlayer::GetCurrentTime() {
@@ -294,6 +297,7 @@ base::TimeDelta MediaSourcePlayer::GetDuration() {
 void MediaSourcePlayer::Release() {
   audio_decoder_job_.reset();
   video_decoder_job_.reset();
+  active_decoding_tasks_ = 0;
   ReleaseMediaResourcesFromManager();
 }
 
@@ -348,41 +352,67 @@ void MediaSourcePlayer::DemuxerReady(
 
 void MediaSourcePlayer::ReadFromDemuxerAck(
     const MediaPlayerHostMsg_ReadFromDemuxerAck_Params& params) {
+  if (params.type == DemuxerStream::AUDIO)
+    waiting_for_audio_data_ = false;
+  else
+    waiting_for_video_data_ = false;
+
+  // If there is a pending seek request, ignore the data from the chunk demuxer.
+  // The data will be requested later when OnSeekRequestAck() is called.
+  if (pending_media_seek_request_)
+    return;
+
   if (params.type == DemuxerStream::AUDIO) {
     DCHECK_EQ(0u, audio_access_unit_index_);
     received_audio_ = params;
-    waiting_for_audio_data_ = false;
     DecodeMoreAudio();
   } else {
     DCHECK_EQ(0u, video_access_unit_index_);
     received_video_ = params;
-    waiting_for_video_data_ = false;
     DecodeMoreVideo();
   }
 }
 
+void MediaSourcePlayer::OnSeekRequestAck() {
+  pending_media_seek_request_ = false;
+  OnSeekComplete();
+  if (!playing_)
+    return;
+
+  if (HasAudio())
+    DecodeMoreAudio();
+  if (HasVideo())
+    DecodeMoreVideo();
+}
+
 void MediaSourcePlayer::UpdateTimestamps(
-    const base::Time& kickoff_time,
     const base::TimeDelta& presentation_timestamp,
     const base::Time& wallclock_time) {
-  // If the job was posted after last seek, update the presentation time.
-  // Otherwise, ignore it.
-  if (kickoff_time > last_seek_time_) {
-    last_presentation_timestamp_ = presentation_timestamp;
-    OnTimeUpdated();
-    if (start_wallclock_time_.is_null() && playing_) {
-      start_wallclock_time_ = wallclock_time;
-      start_presentation_timestamp_ = last_presentation_timestamp_;
-    }
+  last_presentation_timestamp_ = presentation_timestamp;
+  OnTimeUpdated();
+  if (start_wallclock_time_.is_null() && playing_) {
+    start_wallclock_time_ = wallclock_time;
+    start_presentation_timestamp_ = last_presentation_timestamp_;
   }
 }
 
 void MediaSourcePlayer::MediaDecoderCallback(
-    bool is_audio, const base::Time& kickoff_time,
-    const base::TimeDelta& presentation_timestamp,
+    bool is_audio, const base::TimeDelta& presentation_timestamp,
     const base::Time& wallclock_time, bool end_of_stream) {
+  if (active_decoding_tasks_ > 0)
+    active_decoding_tasks_--;
+
+  if (pending_media_seek_request_) {
+    // Wait for all the decoding jobs to finish before sending a seek request.
+    if (!active_decoding_tasks_) {
+      manager()->OnMediaSeekRequest(player_id(),
+                                    last_presentation_timestamp_);
+    }
+    return;
+  }
+
   if (is_audio || !HasAudio())
-    UpdateTimestamps(kickoff_time, presentation_timestamp, wallclock_time);
+    UpdateTimestamps(presentation_timestamp, wallclock_time);
 
   if (end_of_stream) {
     PlaybackCompleted(is_audio);
@@ -413,8 +443,9 @@ void MediaSourcePlayer::DecodeMoreAudio() {
       received_audio_.access_units[audio_access_unit_index_],
       start_wallclock_time_, start_presentation_timestamp_,
       base::Bind(&MediaSourcePlayer::MediaDecoderCallback,
-                 weak_this_.GetWeakPtr(), true, base::Time::Now()));
-  ++audio_access_unit_index_;
+                 weak_this_.GetWeakPtr(), true));
+  active_decoding_tasks_++;
+  audio_access_unit_index_++;
 }
 
 void MediaSourcePlayer::DecodeMoreVideo() {
@@ -432,8 +463,9 @@ void MediaSourcePlayer::DecodeMoreVideo() {
       received_video_.access_units[video_access_unit_index_],
       start_wallclock_time_, start_presentation_timestamp_,
       base::Bind(&MediaSourcePlayer::MediaDecoderCallback,
-                 weak_this_.GetWeakPtr(), false, base::Time::Now()));
-  ++video_access_unit_index_;
+                 weak_this_.GetWeakPtr(), false));
+  active_decoding_tasks_++;
+  video_access_unit_index_++;
 }