Avoids irregular OnMoreData callbacks on Windows using Core Audio

media/audio/win/core_audio_util_win.cc

Index: media/audio/win/core_audio_util_win.cc
diff --git a/media/audio/win/core_audio_util_win.cc b/media/audio/win/core_audio_util_win.cc
index 2c262b4e72d37026199881a3fdaae3ef37601964..efa796ae0c602a851a5660c2bdb77f12d63a1c4f 100644
--- a/media/audio/win/core_audio_util_win.cc
+++ b/media/audio/win/core_audio_util_win.cc
@@ -138,7 +138,7 @@ AUDCLNT_SHAREMODE CoreAudioUtil::GetShareMode() {
 }
 
 int CoreAudioUtil::NumberOfActiveDevices(EDataFlow data_flow) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   // Create the IMMDeviceEnumerator interface.
   ScopedComPtr<IMMDeviceEnumerator> device_enumerator =
       CreateDeviceEnumerator();
@@ -166,7 +166,7 @@ int CoreAudioUtil::NumberOfActiveDevices(EDataFlow data_flow) {
 }
 
 ScopedComPtr<IMMDeviceEnumerator> CoreAudioUtil::CreateDeviceEnumerator() {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMDeviceEnumerator> device_enumerator;
   HRESULT hr = CoCreateInstance(__uuidof(MMDeviceEnumerator),
                                 NULL,
@@ -181,7 +181,7 @@ ScopedComPtr<IMMDeviceEnumerator> CoreAudioUtil::CreateDeviceEnumerator() {
 
 ScopedComPtr<IMMDevice> CoreAudioUtil::CreateDefaultDevice(EDataFlow data_flow,
                                                            ERole role) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMDevice> endpoint_device;
 
   // Create the IMMDeviceEnumerator interface.
@@ -216,7 +216,7 @@ ScopedComPtr<IMMDevice> CoreAudioUtil::CreateDefaultDevice(EDataFlow data_flow,
 
 ScopedComPtr<IMMDevice> CoreAudioUtil::CreateDevice(
     const std::string& device_id) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMDevice> endpoint_device;
 
   // Create the IMMDeviceEnumerator interface.
@@ -235,7 +235,7 @@ ScopedComPtr<IMMDevice> CoreAudioUtil::CreateDevice(
 }
 
 HRESULT CoreAudioUtil::GetDeviceName(IMMDevice* device, AudioDeviceName* name) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
 
   // Retrieve unique name of endpoint device.
   // Example: "{0.0.1.00000000}.{8db6020f-18e3-4f25-b6f5-7726c9122574}".
@@ -270,7 +270,7 @@ HRESULT CoreAudioUtil::GetDeviceName(IMMDevice* device, AudioDeviceName* name) {
 }
 
 std::string CoreAudioUtil::GetFriendlyName(const std::string& device_id) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMDevice> audio_device = CreateDevice(device_id);
   if (!audio_device)
     return std::string();
@@ -286,7 +286,7 @@ std::string CoreAudioUtil::GetFriendlyName(const std::string& device_id) {
 bool CoreAudioUtil::DeviceIsDefault(EDataFlow flow,
                                     ERole role,
                                     std::string device_id) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMDevice> device = CreateDefaultDevice(flow, role);
   if (!device)
     return false;
@@ -304,7 +304,7 @@ bool CoreAudioUtil::DeviceIsDefault(EDataFlow flow,
 }
 
 EDataFlow CoreAudioUtil::GetDataFlow(IMMDevice* device) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMEndpoint> endpoint;
   HRESULT hr = device->QueryInterface(endpoint.Receive());
   if (FAILED(hr)) {
@@ -323,7 +323,7 @@ EDataFlow CoreAudioUtil::GetDataFlow(IMMDevice* device) {
 
 ScopedComPtr<IAudioClient> CoreAudioUtil::CreateClient(
     IMMDevice* audio_device) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
 
   // Creates and activates an IAudioClient COM object given the selected
   // endpoint device.
@@ -338,7 +338,7 @@ ScopedComPtr<IAudioClient> CoreAudioUtil::CreateClient(
 
 ScopedComPtr<IAudioClient> CoreAudioUtil::CreateDefaultClient(
     EDataFlow data_flow, ERole role) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedComPtr<IMMDevice> default_device(CreateDefaultDevice(data_flow, role));
   return (default_device ? CreateClient(default_device) :
       ScopedComPtr<IAudioClient>());
@@ -346,7 +346,7 @@ ScopedComPtr<IAudioClient> CoreAudioUtil::CreateDefaultClient(
 
 HRESULT CoreAudioUtil::GetSharedModeMixFormat(
     IAudioClient* client, WAVEFORMATPCMEX* format) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedCoMem<WAVEFORMATPCMEX> format_pcmex;
   HRESULT hr = client->GetMixFormat(
       reinterpret_cast<WAVEFORMATEX**>(&format_pcmex));
@@ -371,10 +371,22 @@ HRESULT CoreAudioUtil::GetSharedModeMixFormat(
   return hr;
 }
 
+HRESULT CoreAudioUtil::GetDefaultSharedModeMixFormat(
+    EDataFlow data_flow, ERole role, WAVEFORMATPCMEX* format) {
+  DCHECK(IsSupported());
+  ScopedComPtr<IAudioClient> client(CreateDefaultClient(data_flow, role));
+  if (!client) {
+    // Map NULL-pointer to new error code which can be different from the
+    // actual error code. The exact value is not important here.
+    return AUDCLNT_E_ENDPOINT_CREATE_FAILED;
+  }
+  return CoreAudioUtil::GetSharedModeMixFormat(client, format);
+}
+
 bool CoreAudioUtil::IsFormatSupported(IAudioClient* client,
                                       AUDCLNT_SHAREMODE share_mode,
                                       const WAVEFORMATPCMEX* format) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   ScopedCoMem<WAVEFORMATEXTENSIBLE> closest_match;
   HRESULT hr = client->IsFormatSupported(
       share_mode, reinterpret_cast<const WAVEFORMATEX*>(format),
@@ -398,7 +410,7 @@ bool CoreAudioUtil::IsFormatSupported(IAudioClient* client,
 HRESULT CoreAudioUtil::GetDevicePeriod(IAudioClient* client,
                                        AUDCLNT_SHAREMODE share_mode,
                                        REFERENCE_TIME* device_period) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
 
   // Get the period of the engine thread.
   REFERENCE_TIME default_period = 0;
@@ -417,7 +429,7 @@ HRESULT CoreAudioUtil::GetDevicePeriod(IAudioClient* client,
 
 HRESULT CoreAudioUtil::GetPreferredAudioParameters(
     IAudioClient* client, AudioParameters* params) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
   WAVEFORMATPCMEX format;
   HRESULT hr = GetSharedModeMixFormat(client, &format);
   if (FAILED(hr))
@@ -468,9 +480,8 @@ HRESULT CoreAudioUtil::GetPreferredAudioParameters(
 
 HRESULT CoreAudioUtil::GetPreferredAudioParameters(
     EDataFlow data_flow, ERole role, AudioParameters* params) {
-  DCHECK(CoreAudioUtil::IsSupported());
-
-  ScopedComPtr<IAudioClient> client = CreateDefaultClient(data_flow, role);
+  DCHECK(IsSupported());
+  ScopedComPtr<IAudioClient> client(CreateDefaultClient(data_flow, role));
   if (!client) {
     // Map NULL-pointer to new error code which can be different from the
     // actual error code. The exact value is not important here.
@@ -483,8 +494,7 @@ HRESULT CoreAudioUtil::SharedModeInitialize(IAudioClient* client,
                                             const WAVEFORMATPCMEX* format,
                                             HANDLE event_handle,
                                             size_t* endpoint_buffer_size) {
-  DCHECK(CoreAudioUtil::IsSupported());
-
+  DCHECK(IsSupported());
   DWORD stream_flags = AUDCLNT_STREAMFLAGS_NOPERSIST;
 
   // Enable event-driven streaming if a valid event handle is provided.
@@ -538,7 +548,7 @@ HRESULT CoreAudioUtil::SharedModeInitialize(IAudioClient* client,
 
 ScopedComPtr<IAudioRenderClient> CoreAudioUtil::CreateRenderClient(
     IAudioClient* client) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
 
   // Get access to the IAudioRenderClient interface. This interface
   // enables us to write output data to a rendering endpoint buffer.
@@ -549,40 +559,12 @@ ScopedComPtr<IAudioRenderClient> CoreAudioUtil::CreateRenderClient(
     DVLOG(1) << "IAudioClient::GetService: " << std::hex << hr;
     return ScopedComPtr<IAudioRenderClient>();
   }
-
-  // TODO(henrika): verify that this scheme is the same for shared mode and
-  // exclusive mode streams.
-
-  // Avoid start-up glitches by filling up the endpoint buffer with "silence"
-  // before starting the stream.
-  UINT32 endpoint_buffer_size = 0;
-  hr = client->GetBufferSize(&endpoint_buffer_size);
-  DVLOG_IF(1, FAILED(hr)) << "IAudioClient::GetBufferSize: " << std::hex << hr;
-
-  BYTE* data = NULL;
-  hr = audio_render_client->GetBuffer(endpoint_buffer_size, &data);
-  DVLOG_IF(1, FAILED(hr)) << "IAudioRenderClient::GetBuffer: "
-                          << std::hex << hr;
-  if (SUCCEEDED(hr)) {
-    // Using the AUDCLNT_BUFFERFLAGS_SILENT flag eliminates the need to
-    // explicitly write silence data to the rendering buffer.
-    hr = audio_render_client->ReleaseBuffer(endpoint_buffer_size,
-                                            AUDCLNT_BUFFERFLAGS_SILENT);
-    DVLOG_IF(1, FAILED(hr)) << "IAudioRenderClient::ReleaseBuffer: "
-                            << std::hex << hr;
-  }
-
-  // Sanity check: verify that the endpoint buffer is filled with silence.
-  UINT32 num_queued_frames = 0;
-  client->GetCurrentPadding(&num_queued_frames);
-  DCHECK(num_queued_frames == endpoint_buffer_size);
-
   return audio_render_client;
 }
 
 ScopedComPtr<IAudioCaptureClient> CoreAudioUtil::CreateCaptureClient(
     IAudioClient* client) {
-  DCHECK(CoreAudioUtil::IsSupported());
+  DCHECK(IsSupported());
 
   // Get access to the IAudioCaptureClient interface. This interface
   // enables us to read input data from a capturing endpoint buffer.
@@ -596,4 +578,28 @@ ScopedComPtr<IAudioCaptureClient> CoreAudioUtil::CreateCaptureClient(
   return audio_capture_client;
 }
 
+bool CoreAudioUtil::FillRenderEndpointBufferWithSilence(
+    IAudioClient* client, IAudioRenderClient* render_client) {
+  DCHECK(IsSupported());
+
+  UINT32 endpoint_buffer_size = 0;
+  if (FAILED(client->GetBufferSize(&endpoint_buffer_size)))
+    return false;
+
+  UINT32 num_queued_frames = 0;
+  if (FAILED(client->GetCurrentPadding(&num_queued_frames)))
+    return false;
+
+  BYTE* data = NULL;
+  int num_frames_to_fill = endpoint_buffer_size - num_queued_frames;
+  if (FAILED(render_client->GetBuffer(num_frames_to_fill, &data)))
+    return false;
+
+  // Using the AUDCLNT_BUFFERFLAGS_SILENT flag eliminates the need to
+  // explicitly write silence data to the rendering buffer.
+  DVLOG(2) << "filling up " << num_frames_to_fill << " frames with silence";
+  return SUCCEEDED(render_client->ReleaseBuffer(num_frames_to_fill,
+                                                AUDCLNT_BUFFERFLAGS_SILENT));
+}
+
 }  // namespace media