commit a6f2c7b1ac67075197ccbaba61e5e23277aab5f7
author Glenn Kasten <gkasten@google.com> Fri Oct 18 13:00:29 2013 -0700
committer The Android Automerger <android-build@google.com> Sun Oct 20 12:32:53 2013 -0700
tree f872e4b7570cf2f431cca474e47d9d10c6cbed66
parent 6a99d2058d0e5afed3643367166abee6b978209f

Allow releaseBuffer after flush

After AudioTrack start checks for pending flush,
allow releaseBuffer on any previously obtained buffer.
For example, this can happen if the resampler has obtained
a buffer but not released the whole buffer yet.
Note that the resampler will be reading obsolete data.

Bug: 11285590
Change-Id: I0614fbb62e43604aac3089cce4b7797c87a306b5

include/private/media/AudioTrackShared.h

diff --git a/include/private/media/AudioTrackShared.h b/include/private/media/AudioTrackShared.h
index 395f164..7fd9379 100644
--- a/include/private/media/AudioTrackShared.h
+++ b/include/private/media/AudioTrackShared.h
@@ -360,6 +360,7 @@
     //      which must be > 0.
     //  buffer->mNonContig is unused.
     //  buffer->mRaw is unused.
+    //  ackFlush is true iff being called from Track::start to acknowledge a pending flush.
     // On exit:
     //  buffer->mFrameCount has the actual number of contiguous available frames,
     //      which is always 0 when the return status != NO_ERROR.
@@ -370,7 +371,7 @@
     //  NO_ERROR    Success, buffer->mFrameCount > 0.
     //  WOULD_BLOCK No frames are available.
     //  NO_INIT     Shared memory is corrupt.
-    virtual status_t    obtainBuffer(Buffer* buffer);
+    virtual status_t    obtainBuffer(Buffer* buffer, bool ackFlush = false);
 
     // Release (some of) the frames last obtained.
     // On entry, buffer->mFrameCount should have the number of frames to release,
@@ -437,7 +438,7 @@
 public:
     virtual size_t      framesReady();
     virtual void        framesReadyIsCalledByMultipleThreads();
-    virtual status_t    obtainBuffer(Buffer* buffer);
+    virtual status_t    obtainBuffer(Buffer* buffer, bool ackFlush);
     virtual void        releaseBuffer(Buffer* buffer);
     virtual void        tallyUnderrunFrames(uint32_t frameCount);
     virtual uint32_t    getUnderrunFrames() const { return 0; }

media/libmedia/AudioTrackShared.cpp

diff --git a/media/libmedia/AudioTrackShared.cpp b/media/libmedia/AudioTrackShared.cpp
index da73d65..caa7900 100644
--- a/media/libmedia/AudioTrackShared.cpp
+++ b/media/libmedia/AudioTrackShared.cpp
@@ -506,7 +506,7 @@
 {
 }
 
-status_t ServerProxy::obtainBuffer(Buffer* buffer)
+status_t ServerProxy::obtainBuffer(Buffer* buffer, bool ackFlush)
 {
     LOG_ALWAYS_FATAL_IF(buffer == NULL || buffer->mFrameCount == 0);
     if (mIsShutdown) {
@@ -579,7 +579,11 @@
     buffer->mRaw = part1 > 0 ?
             &((char *) mBuffers)[(mIsOut ? front : rear) * mFrameSize] : NULL;
     buffer->mNonContig = availToServer - part1;
-    mUnreleased = part1;
+    // After flush(), allow releaseBuffer() on a previously obtained buffer;
+    // see "Acknowledge any pending flush()" in audioflinger/Tracks.cpp.
+    if (!ackFlush) {
+        mUnreleased = part1;
+    }
     return part1 > 0 ? NO_ERROR : WOULD_BLOCK;
     }
 no_init:
@@ -761,7 +765,7 @@
     return (ssize_t) position;
 }
 
-status_t StaticAudioTrackServerProxy::obtainBuffer(Buffer* buffer)
+status_t StaticAudioTrackServerProxy::obtainBuffer(Buffer* buffer, bool ackFlush)
 {
     if (mIsShutdown) {
         buffer->mFrameCount = 0;

services/audioflinger/Tracks.cpp

diff --git a/services/audioflinger/Tracks.cpp b/services/audioflinger/Tracks.cpp
index e93833f..363bc9d 100644
--- a/services/audioflinger/Tracks.cpp
+++ b/services/audioflinger/Tracks.cpp
@@ -608,7 +608,7 @@
             // and for fast tracks the track is not yet in the fast mixer thread's active set.
             ServerProxy::Buffer buffer;
             buffer.mFrameCount = 1;
-            (void) mAudioTrackServerProxy->obtainBuffer(&buffer);
+            (void) mAudioTrackServerProxy->obtainBuffer(&buffer, true /*ackFlush*/);
         }
     } else {
         status = BAD_VALUE;