libmedia: offloaded playback support

- start() returns a status so that upper layers can
recreate a non offloaded track in case of error.

- Added states to handle offloaded tracks specific:
  - waiting for stream end (drain) notification by
audio flinger
  - allow pause while waiting for stream end notification

- getPosition() queries the render position directly from
audio HAL.

- disable APIs not applicable to offloaded tracks

- Modified track restoring behavior for invalidated
offloaded tracks: just send the callback and wait for
upper layers to create a new track.

- Added wait for stream end management in audio track client
proxy. Similar to obtainBuffer and should be factored in.

Change-Id: I0fc48117946364cb255afd653195498891f622bd
Signed-off-by: Eric Laurent <elaurent@google.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/private/media/AudioTrackShared.h b/include/private/media/AudioTrackShared.h
index 6129c80..b890180 100644
--- a/include/private/media/AudioTrackShared.h
+++ b/include/private/media/AudioTrackShared.h
@@ -296,6 +296,7 @@ public:
 
     bool        getStreamEndDone() const;
 
+    status_t    waitStreamEndDone(const struct timespec *requested);
 };
 
 class StaticAudioTrackClientProxy : public AudioTrackClientProxy {
@@ -379,8 +380,8 @@ public:
 
 protected:
     size_t      mAvailToClient; // estimated frames available to client prior to releaseBuffer()
-private:
     int32_t     mFlush;         // our copy of cblk->u.mStreaming.mFlush, for streaming output only
+private:
     bool        mDeferWake;     // whether another releaseBuffer() is expected soon
 };