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, 7 insertions, 15 deletions

diff --git a/media/libmedia/ToneGenerator.cpp b/media/libmedia/ToneGenerator.cpp
index f55b697..ebe1ba1 100644
--- a/media/libmedia/ToneGenerator.cpp
+++ b/media/libmedia/ToneGenerator.cpp
@@ -803,7 +803,6 @@ ToneGenerator::ToneGenerator(audio_stream_type_t streamType, float volume, bool
     ALOGV("ToneGenerator constructor: streamType=%d, volume=%f", streamType, volume);
 
     mState = TONE_IDLE;
-    mpAudioTrack = NULL;
 
     if (AudioSystem::getOutputSamplingRate(&mSamplingRate, streamType) != NO_ERROR) {
         ALOGE("Unable to marshal AudioFlinger");
@@ -855,10 +854,10 @@ ToneGenerator::ToneGenerator(audio_stream_type_t streamType, float volume, bool
 ToneGenerator::~ToneGenerator() {
     ALOGV("ToneGenerator destructor");
 
-    if (mpAudioTrack != NULL) {
+    if (mpAudioTrack != 0) {
         stopTone();
-        ALOGV("Delete Track: %p", mpAudioTrack);
-        delete mpAudioTrack;
+        ALOGV("Delete Track: %p", mpAudioTrack.get());
+        mpAudioTrack.clear();
     }
 }
 
@@ -1047,14 +1046,9 @@ void ToneGenerator::stopTone() {
 ////////////////////////////////////////////////////////////////////////////////
 bool ToneGenerator::initAudioTrack() {
 
-    if (mpAudioTrack) {
-        delete mpAudioTrack;
-        mpAudioTrack = NULL;
-    }
-
     // Open audio track in mono, PCM 16bit, default sampling rate, default buffer size
     mpAudioTrack = new AudioTrack();
-    ALOGV("Create Track: %p", mpAudioTrack);
+    ALOGV("Create Track: %p", mpAudioTrack.get());
 
     mpAudioTrack->set(mStreamType,
                       0,    // sampleRate
@@ -1081,12 +1075,10 @@ bool ToneGenerator::initAudioTrack() {
 
 initAudioTrack_exit:
 
+    ALOGV("Init failed: %p", mpAudioTrack.get());
+
     // Cleanup
-    if (mpAudioTrack != NULL) {
-        ALOGV("Delete Track I: %p", mpAudioTrack);
-        delete mpAudioTrack;
-        mpAudioTrack = NULL;
-    }
+    mpAudioTrack.clear();
 
     return false;
 }