Merge "Add comments"

3 files changed, 10 insertions, 1 deletions

diff --git a/media/libmedia/AudioSystem.cpp b/media/libmedia/AudioSystem.cpp
index 5de46bb..6b9b3be 100644
--- a/media/libmedia/AudioSystem.cpp
+++ b/media/libmedia/AudioSystem.cpp
@@ -537,6 +537,8 @@ const sp<IAudioPolicyService>& AudioSystem::get_audio_policy_service()
     return gAudioPolicyService;
 }
 
+// ---------------------------------------------------------------------------
+
 status_t AudioSystem::setDeviceConnectionState(audio_devices_t device,
                                                audio_policy_dev_state_t state,
                                                const char *device_address)
diff --git a/media/libmedia/AudioTrack.cpp b/media/libmedia/AudioTrack.cpp
index 00f4640..7b6b38d 100644
--- a/media/libmedia/AudioTrack.cpp
+++ b/media/libmedia/AudioTrack.cpp
@@ -585,6 +585,7 @@ void AudioTrack::setLoop_l(uint32_t loopStart, uint32_t loopEnd, int loopCount)
 
 status_t AudioTrack::setMarkerPosition(uint32_t marker)
 {
+    // The only purpose of setting marker position is to get a callback
     if (mCbf == NULL) {
         return INVALID_OPERATION;
     }
@@ -610,6 +611,7 @@ status_t AudioTrack::getMarkerPosition(uint32_t *marker) const
 
 status_t AudioTrack::setPositionUpdatePeriod(uint32_t updatePeriod)
 {
+    // The only purpose of setting position update period is to get a callback
     if (mCbf == NULL) {
         return INVALID_OPERATION;
     }
@@ -1220,6 +1222,11 @@ status_t TimedAudioTrack::setMediaTimeTransform(const LinearTransform& xform,
 
 nsecs_t AudioTrack::processAudioBuffer(const sp<AudioTrackThread>& thread)
 {
+    // Currently the AudioTrack thread is not created if there are no callbacks.
+    // Would it ever make sense to run the thread, even without callbacks?
+    // If so, then replace this by checks at each use for mCbf != NULL.
+    LOG_ALWAYS_FATAL_IF(mCblk == NULL);
+
     mLock.lock();
     if (mAwaitBoost) {
         mAwaitBoost = false;
diff --git a/media/libmediaplayerservice/MidiFile.cpp b/media/libmediaplayerservice/MidiFile.cpp
index 8db5b9b..270b872 100644
--- a/media/libmediaplayerservice/MidiFile.cpp
+++ b/media/libmediaplayerservice/MidiFile.cpp
@@ -422,7 +422,7 @@ status_t MidiFile::setLooping(int loop)
 
 status_t MidiFile::createOutputTrack() {
     if (mAudioSink->open(pLibConfig->sampleRate, pLibConfig->numChannels,
-            CHANNEL_MASK_USE_CHANNEL_ORDER, AUDIO_FORMAT_PCM_16_BIT, 2) != NO_ERROR) {
+            CHANNEL_MASK_USE_CHANNEL_ORDER, AUDIO_FORMAT_PCM_16_BIT, 2 /*bufferCount*/) != NO_ERROR) {
         ALOGE("mAudioSink open failed");
         return ERROR_OPEN_FAILED;
     }