Stop enqueueing data to output audio device if consecutive empty buffers are received

media/audio/android/audio_android_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/android/build_info.h"
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 386 matching lines @@
   AudioParameters params_;
   base::TimeTicks previous_time_;
   base::Lock lock_;
   scoped_ptr<media::SeekableBuffer> fifo_;
   scoped_ptr<uint8[]> buffer_;
   bool started_;
 
   DISALLOW_COPY_AND_ASSIGN(FullDuplexAudioSinkSource);
 };
 
+// Implements AudioOutputStream::AudioSourceCallback and provides empty audio
+// data.
+class EmptyAudioSource : public AudioOutputStream::AudioSourceCallback {
+ public:
+  EmptyAudioSource(base::WaitableEvent* event, int size)
+      : event_(event), remaining_size_(size) {}
+  ~EmptyAudioSource() override {}
+
+  // AudioOutputStream::AudioSourceCallback implementation.
+  int OnMoreData(AudioBus* audio_bus, uint32 total_bytes_delay) override {
+    audio_bus->Zero();
+    int max_size =
+        audio_bus->frames() * audio_bus->channels() * kBytesPerSample;
+    bool stop_playing = false;
+    if (max_size > remaining_size_) {
+      stop_playing = true;
+      max_size = remaining_size_;
+    }
+    remaining_size_ -= max_size;
+    // Set event to ensure that the test can stop.
+    if (stop_playing)
+      event_->Signal();
+
+    return max_size / (audio_bus->channels() * kBytesPerSample);
+  }
+
+  void OnError(AudioOutputStream* stream) override {}
+
+ private:
+  base::WaitableEvent* event_;
+  int remaining_size_;
+
+  DISALLOW_COPY_AND_ASSIGN(EmptyAudioSource);
+};
+
 // Test fixture class for tests which only exercise the output path.
 class AudioAndroidOutputTest : public testing::Test {
  public:
   AudioAndroidOutputTest()
       : loop_(new base::MessageLoopForUI()),
         audio_manager_(AudioManager::CreateForTesting()),
         audio_output_stream_(NULL) {
   }
 
   ~AudioAndroidOutputTest() override {}
@@ skipping 439 matching lines @@
 
   base::WaitableEvent event(false, false);
   FileAudioSource source(&event, file_name);
 
   OpenAndStartAudioOutputStreamOnAudioThread(&source);
   DVLOG(0) << ">> Verify that the file is played out correctly...";
   EXPECT_TRUE(event.TimedWait(TestTimeouts::action_max_timeout()));
   StopAndCloseAudioOutputStreamOnAudioThread();
 }
 
+// Play empty data and verify that the data are consumed properly.
+TEST_F(AudioAndroidOutputTest, RunOutputStreamWithEmptySource) {
+  GetDefaultOutputStreamParametersOnAudioThread();
+  const AudioParameters params = audio_output_parameters();
+  DVLOG(1) << params;
+  MakeAudioOutputStreamOnAudioThread(params);
+
+  base::WaitableEvent event(false, false);
+  int size = 100000;
+  EmptyAudioSource source(&event, size);
+  base::TimeTicks start_time = base::TimeTicks::Now();
+
+  OpenAndStartAudioOutputStreamOnAudioThread(&source);
+  EXPECT_TRUE(event.TimedWait(TestTimeouts::action_max_timeout()));
+  // Verify that all the data are consumed as if they are passed through audio
+  // hardware.
+  base::TimeDelta time_passed = base::TimeTicks::Now() - start_time;
+  int estimated_consumption_time_ms = (size * 1000) /
+      (params.channels() * params.sample_rate() * kBytesPerSample);
+  EXPECT_LE(estimated_consumption_time_ms, time_passed.InMilliseconds());
+  StopAndCloseAudioOutputStreamOnAudioThread();
+}
+
 // Start input streaming and run it for ten seconds while recording to a
 // local audio file.
 // NOTE: this test requires user interaction and is not designed to run as an
 // automatized test on bots.
 TEST_P(AudioAndroidInputTest, DISABLED_RunSimplexInputStreamWithFileAsSink) {
   AudioParameters params = GetInputStreamParameters();
   DVLOG(1) << params;
   MakeAudioInputStreamOnAudioThread(params);
 
   std::string file_name = base::StringPrintf("out_simplex_%d_%d_%d.pcm",
@@ skipping 88 matching lines @@
   base::PlatformThread::Sleep(base::TimeDelta::FromSeconds(20));
   printf("\n");
   StopAndCloseAudioOutputStreamOnAudioThread();
   StopAndCloseAudioInputStreamOnAudioThread();
 }
 
 INSTANTIATE_TEST_CASE_P(AudioAndroidInputTest, AudioAndroidInputTest,
     testing::ValuesIn(RunAudioRecordInputPathTests()));
 
 }  // namespace media