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

5 files changed, 9 insertions, 7 deletions

diff --git a/include/media/AudioTrack.h b/include/media/AudioTrack.h
index 0b616e3..8dbc9ee 100644
--- a/include/media/AudioTrack.h
+++ b/include/media/AudioTrack.h
@@ -191,7 +191,9 @@ public:
     /* Terminates the AudioTrack and unregisters it from AudioFlinger.
      * Also destroys all resources associated with the AudioTrack.
      */
-                        ~AudioTrack();
+protected:
+                        virtual ~AudioTrack();
+public:
 
     /* Initialize an uninitialized AudioTrack.
      * Returned status (from utils/Errors.h) can be:
diff --git a/include/media/JetPlayer.h b/include/media/JetPlayer.h
index 0616bf0..388f767 100644
--- a/include/media/JetPlayer.h
+++ b/include/media/JetPlayer.h
@@ -88,7 +88,7 @@ private:
     EAS_DATA_HANDLE     mEasData;
     EAS_FILE_LOCATOR    mEasJetFileLoc;
     EAS_PCM*            mAudioBuffer;// EAS renders the MIDI data into this buffer,
-    AudioTrack*         mAudioTrack; // and we play it in this audio track
+    sp<AudioTrack>      mAudioTrack; // and we play it in this audio track
     int                 mTrackBufferSize;
     S_JET_STATUS        mJetStatus;
     S_JET_STATUS        mPreviousJetStatus;
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;
diff --git a/include/media/ToneGenerator.h b/include/media/ToneGenerator.h
index 2183fbe..98c4332 100644
--- a/include/media/ToneGenerator.h
+++ b/include/media/ToneGenerator.h
@@ -160,7 +160,7 @@ public:
     bool isInited() { return (mState == TONE_IDLE)?false:true;}
 
     // returns the audio session this ToneGenerator belongs to or 0 if an error occured.
-    int getSessionId() { return (mpAudioTrack == NULL) ? 0 : mpAudioTrack->getSessionId(); }
+    int getSessionId() { return (mpAudioTrack == 0) ? 0 : mpAudioTrack->getSessionId(); }
 
 private:
 
@@ -264,7 +264,7 @@ private:
     unsigned short mLoopCounter; // Current tone loopback count
 
     uint32_t mSamplingRate;  // AudioFlinger Sampling rate
-    AudioTrack *mpAudioTrack;  // Pointer to audio track used for playback
+    sp<AudioTrack> mpAudioTrack;  // Pointer to audio track used for playback
     Mutex mLock;  // Mutex to control concurent access to ToneGenerator object from audio callback and application API
     Mutex mCbkCondLock; // Mutex associated to mWaitCbkCond
     Condition mWaitCbkCond; // condition enabling interface to wait for audio callback completion after a change is requested
diff --git a/include/media/stagefright/AudioPlayer.h b/include/media/stagefright/AudioPlayer.h
index 1dc408f..3bf046d 100644
--- a/include/media/stagefright/AudioPlayer.h
+++ b/include/media/stagefright/AudioPlayer.h
@@ -70,7 +70,7 @@ public:
 private:
     friend class VideoEditorAudioPlayer;
     sp<MediaSource> mSource;
-    AudioTrack *mAudioTrack;
+    sp<AudioTrack> mAudioTrack;
 
     MediaBuffer *mInputBuffer;