Adding audio unit tests for Android

media/audio/android/opensles_output.h

Index: media/audio/android/opensles_output.h
diff --git a/media/audio/android/opensles_output.h b/media/audio/android/opensles_output.h
index f505b5165cd4d2016ef3560d3a47e270c65c5977..7232d5da5f76210dee252f44946d141d075e19be 100644
--- a/media/audio/android/opensles_output.h
+++ b/media/audio/android/opensles_output.h
@@ -9,6 +9,8 @@
 #include <SLES/OpenSLES_Android.h>
 
 #include "base/compiler_specific.h"
+#include "base/synchronization/lock.h"
+#include "base/threading/thread_checker.h"
 #include "media/audio/android/opensles_util.h"
 #include "media/audio/audio_io.h"
 #include "media/audio/audio_parameters.h"
@@ -18,9 +20,12 @@ namespace media {
 class AudioManagerAndroid;
 
 // Implements PCM audio output support for Android using the OpenSLES API.
+// This class is created and lives on the Audio Manager thread but recorded
+// audio buffers are given to us from an internal OpenSLES audio thread.
+// All public methods should be called on the Audio Manager thread.
 class OpenSLESOutputStream : public AudioOutputStream {
  public:
-  static const int kNumOfQueuesInBuffer = 2;
+  static const int kMaxNumOfBuffersInQueue = 2;
 
   OpenSLESOutputStream(AudioManagerAndroid* manager,
                        const AudioParameters& params);
@@ -38,11 +43,18 @@ class OpenSLESOutputStream : public AudioOutputStream {
  private:
   bool CreatePlayer();
 
+  // Called from OpenSLES specific audio worker thread.
   static void SimpleBufferQueueCallback(
-      SLAndroidSimpleBufferQueueItf buffer_queue, void* instance);
+      SLAndroidSimpleBufferQueueItf buffer_queue,
+      void* instance);
 
+  // Fills up one buffer by asking the registered source for data.
+  // Called from OpenSLES specific audio worker thread.
   void FillBufferQueue();
 
+  // Called from the audio manager thread.
+  void FillBufferQueueNoLock();
+
   // Called in Open();
   void SetupAudioBuffer();
 
@@ -53,6 +65,12 @@ class OpenSLESOutputStream : public AudioOutputStream {
   // the attached AudioOutputCallback::OnError().
   void HandleError(SLresult error);
 
+  base::ThreadChecker thread_checker_;
+
+  // Protects |callback_|, |active_buffer_index_|, |audio_data_|,
+  // |buffer_size_bytes_| and |simple_buffer_queue_|.
+  base::Lock lock_;
+
   AudioManagerAndroid* audio_manager_;
 
   AudioSourceCallback* callback_;
@@ -69,10 +87,11 @@ class OpenSLESOutputStream : public AudioOutputStream {
 
   SLDataFormat_PCM format_;
 
-  // Audio buffer arrays that are allocated in the constructor.
-  uint8* audio_data_[kNumOfQueuesInBuffer];
+  // Audio buffers that are allocated in the constructor based on
+  // info from audio parameters.
+  uint8* audio_data_[kMaxNumOfBuffersInQueue];
 
-  int active_queue_;
+  int active_buffer_index_;
   size_t buffer_size_bytes_;
 
   bool started_;
@@ -88,4 +107,4 @@ class OpenSLESOutputStream : public AudioOutputStream {
 
 }  // namespace media
 
-#endif  // MEDIA_AUDIO_ANDROID_OPENSLES_INPUT_H_
+#endif  // MEDIA_AUDIO_ANDROID_OPENSLES_OUTPUT_H_