From 598de6c701e989385eeffa7c5dfd61f0459a2631 Mon Sep 17 00:00:00 2001
From: Glenn Kasten <gkasten@google.com>
Date: Wed, 16 Oct 2013 17:02:13 -0700
Subject: Fix race condition in AudioTrack::pause followed by start

Bug: 11148722
Change-Id: Iec88f00c8510363d4418e4b8d5b34feb06ecf04d
---
 include/media/AudioTrack.h    |  1 +
 media/libmedia/AudioTrack.cpp | 15 ++++++++-------
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/include/media/AudioTrack.h b/include/media/AudioTrack.h
index 22ad57e..f2f9c22 100644
--- a/include/media/AudioTrack.h
+++ b/include/media/AudioTrack.h
@@ -612,6 +612,7 @@ protected:
         bool                mPaused;    // whether thread is requested to pause at next loop entry
         bool                mPausedInt; // whether thread internally requests pause
         nsecs_t             mPausedNs;  // if mPausedInt then associated timeout, otherwise ignored
+        bool                mIgnoreNextPausedInt;   // whether to ignore next mPausedInt request
     };
 
             // body of AudioTrackThread::threadLoop()
diff --git a/media/libmedia/AudioTrack.cpp b/media/libmedia/AudioTrack.cpp
index 37d50cf..80f5155 100644
--- a/media/libmedia/AudioTrack.cpp
+++ b/media/libmedia/AudioTrack.cpp
@@ -1785,7 +1785,8 @@ void AudioTrack::DeathNotifier::binderDied(const wp<IBinder>& who)
 // =========================================================================
 
 AudioTrack::AudioTrackThread::AudioTrackThread(AudioTrack& receiver, bool bCanCallJava)
-    : Thread(bCanCallJava), mReceiver(receiver), mPaused(true), mPausedInt(false), mPausedNs(0LL)
+    : Thread(bCanCallJava), mReceiver(receiver), mPaused(true), mPausedInt(false), mPausedNs(0LL),
+      mIgnoreNextPausedInt(false)
 {
 }
 
@@ -1802,6 +1803,10 @@ bool AudioTrack::AudioTrackThread::threadLoop()
             // caller will check for exitPending()
             return true;
         }
+        if (mIgnoreNextPausedInt) {
+            mIgnoreNextPausedInt = false;
+            mPausedInt = false;
+        }
         if (mPausedInt) {
             if (mPausedNs > 0) {
                 (void) mMyCond.waitRelative(mMyLock, mPausedNs);
@@ -1836,12 +1841,7 @@ void AudioTrack::AudioTrackThread::requestExit()
 {
     // must be in this order to avoid a race condition
     Thread::requestExit();
-    AutoMutex _l(mMyLock);
-    if (mPaused || mPausedInt) {
-        mPaused = false;
-        mPausedInt = false;
-        mMyCond.signal();
-    }
+    resume();
 }
 
 void AudioTrack::AudioTrackThread::pause()
@@ -1853,6 +1853,7 @@ void AudioTrack::AudioTrackThread::pause()
 void AudioTrack::AudioTrackThread::resume()
 {
     AutoMutex _l(mMyLock);
+    mIgnoreNextPausedInt = true;
     if (mPaused || mPausedInt) {
         mPaused = false;
         mPausedInt = false;
-- 
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