Initialize the shared memory to appease Valgrind.

BUG=138515
TEST=Under valgrind, run: content_unittests --gtest_filter=AudioDeviceTest.*

Review URL: https://chromiumcodereview.appspot.com/10806061

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@147848 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 32 insertions, 4 deletions

diff --git a/content/renderer/media/audio_device.cc b/content/renderer/media/audio_device.cc
index 22fb7fc..9936ebd 100644
--- a/content/renderer/media/audio_device.cc
+++ b/content/renderer/media/audio_device.cc
@@ -273,8 +273,7 @@ void AudioDevice::AudioThreadCallback::Process(int pending_data) {
   // TODO(crogers/vrk): Figure out a way to avoid the float -> int -> float
   // conversions that happen in the <audio> and WebRTC scenarios.
   media::InterleaveFloatToInt(audio_data_, shared_memory_.memory(),
-      audio_parameters_.frames_per_buffer(),
-      audio_parameters_.bits_per_sample() / 8);
+      num_frames, audio_parameters_.bits_per_sample() / 8);
 
   // Let the host know we are done.
   media::SetActualDataSizeInBytes(&shared_memory_, memory_length_,
diff --git a/content/renderer/media/audio_device_unittest.cc b/content/renderer/media/audio_device_unittest.cc
index adf5506..4612ec7 100644
--- a/content/renderer/media/audio_device_unittest.cc
+++ b/content/renderer/media/audio_device_unittest.cc
@@ -111,6 +111,19 @@ ACTION_P(QuitLoop, loop) {
   loop->PostTask(FROM_HERE, MessageLoop::QuitClosure());
 }
 
+// Zeros out |number_of_frames| in all channel buffers pointed to by
+// the |audio_data| vector.
+void ZeroAudioData(int number_of_frames,
+                   const std::vector<float*>& audio_data) {
+  std::vector<float*>::const_iterator it = audio_data.begin();
+  for (; it != audio_data.end(); ++it) {
+    float* channel = *it;
+    for (int j = 0; j < number_of_frames; ++j) {
+      channel[j] = 0.0f;
+    }
+  }
+}
+
 }  // namespace.
 
 class AudioDeviceTest : public testing::Test {
@@ -197,7 +210,9 @@ TEST_F(AudioDeviceTest, CreateStream) {
   int memory_size = media::TotalSharedMemorySizeInBytes(
       default_audio_parameters_.GetBytesPerBuffer());
   SharedMemory shared_memory;
-  ASSERT_TRUE(shared_memory.CreateAnonymous(memory_size));
+  ASSERT_TRUE(shared_memory.CreateAndMapAnonymous(memory_size));
+  // Initialize the memory.
+  memset(shared_memory.memory(), 0xff, memory_size);
 
   CancelableSyncSocket browser_socket, renderer_socket;
   ASSERT_TRUE(CancelableSyncSocket::CreatePair(&browser_socket,
@@ -226,10 +241,24 @@ TEST_F(AudioDeviceTest, CreateStream) {
   // writing the interleaved audio data into the shared memory section.
   // So, for the sake of this test, we consider the call to Render a sign
   // of success and quit the loop.
+
+  // A note on the call to ZeroAudioData():
+  // Valgrind caught a bug in AudioDevice::AudioThreadCallback::Process()
+  // whereby we always interleaved all the frames in the buffer regardless
+  // of how many were actually rendered.  So to keep the benefits of that
+  // test, we explicitly pass 0 in here as the number of frames to
+  // ZeroAudioData().  Other tests might want to pass the requested number
+  // by using WithArgs<1, 0>(Invoke(&ZeroAudioData)) and set the return
+  // value accordingly.
+  const int kNumberOfFramesToProcess = 0;
+
   EXPECT_CALL(callback_, Render(_, _, _))
       .WillOnce(DoAll(
+          WithArgs<0>(Invoke(
+              testing::CreateFunctor(&ZeroAudioData,
+                  kNumberOfFramesToProcess))),
           QuitLoop(io_loop_.message_loop_proxy()),
-          Return(1)));
+          Return(kNumberOfFramesToProcess)));
 
   audio_device->OnStreamCreated(duplicated_memory_handle, audio_device_socket,
                                 memory_size);