Use sp<AudioTrack> instead of raw AudioTrack *

This change prepares for the new implementation of AudioTrack client, which
will require clients to use only sp<AudioTrack>, not raw AudioTrack *.
A raw delete will cause a race condition during AudioTrack destruction.

AudioTrack was made a RefBase by commit b68a91a70bc8d0d18e7404e14443d4e4020b3635
on 2011/11/15, when it was needed by OpenSL ES (for the callback protector).
At that time, the only other client that was also converted from
AudioTrack * to sp<AudioTrack> was android.media.AudioTrack JNI in
project frameworks/base (file android_media_AudioTrack.cpp).

Details:
 * Use .clear() instead of delete followed by = NULL.
 * ALOG %p need .get().
 * sp<> don't need to be listed in constructor initializer, if initially 0.
 * Use == 0 for sp<> vs == NULL for raw pointers.
 * Use if (sp != 0) instead of if (raw).

Change-Id: Ic7cad25795d6e862e112abdc227b6d33afdfce17

1 files changed, 2 insertions, 2 deletions

diff --git a/include/media/SoundPool.h b/include/media/SoundPool.h
index 7bf3069..9e5654f 100644
--- a/include/media/SoundPool.h
+++ b/include/media/SoundPool.h
@@ -118,7 +118,7 @@ protected:
 class SoundChannel : public SoundEvent {
 public:
     enum state { IDLE, RESUMING, STOPPING, PAUSED, PLAYING };
-    SoundChannel() : mAudioTrack(NULL), mState(IDLE), mNumChannels(1),
+    SoundChannel() : mState(IDLE), mNumChannels(1),
             mPos(0), mToggle(0), mAutoPaused(false) {}
     ~SoundChannel();
     void init(SoundPool* soundPool);
@@ -148,7 +148,7 @@ private:
     bool doStop_l();
 
     SoundPool*          mSoundPool;
-    AudioTrack*         mAudioTrack;
+    sp<AudioTrack>      mAudioTrack;
     SoundEvent          mNextEvent;
     Mutex               mLock;
     int                 mState;