Video Capture Mojo (1.4c): Handle Subsequent Access

services/video_capture/video_capture_device_proxy_impl.cc

 // Copyright 2016 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/logging.h"
 #include "services/video_capture/device_client_mojo_to_media_adapter.h"
 #include "services/video_capture/video_capture_device_proxy_impl.h"
 
 namespace video_capture {
 
 VideoCaptureDeviceProxyImpl::VideoCaptureDeviceProxyImpl(
     std::unique_ptr<media::VideoCaptureDevice> device)
     : device_(std::move(device)) {}
 
 VideoCaptureDeviceProxyImpl::~VideoCaptureDeviceProxyImpl() = default;

[mcasas, 2016/09/02 16:15:15]

Hmm I wonder if we should call Stop() here
as well, or if the VCD implementation(s) do
clean up on destruction.

[chfremer, 2016/09/02 17:44:32]

Thanks for catching this. The VCD description says "StopAndDeAllocate() must be
called/ before the object is deleted". It does not say whether or not it is okay
to call it twice, though, so I'll add a flag to make sure we do not call it
twice when the device is already stopped when the destructor is called.

 
 void VideoCaptureDeviceProxyImpl::Start(
     mojom::VideoCaptureFormatPtr requested_format,
     mojom::ResolutionChangePolicy resolution_change_policy,
     mojom::PowerLineFrequency power_line_frequency,
     mojom::VideoCaptureDeviceClientPtr client) {
   media::VideoCaptureParams params;
   params.requested_format = ConvertFromMojoToMedia(std::move(requested_format));
   params.resolution_change_policy =
       ConvertFromMojoToMedia(resolution_change_policy);
   params.power_line_frequency = ConvertFromMojoToMedia(power_line_frequency);
   auto media_client =
       base::WrapUnique(new DeviceClientMojoToMediaAdapter(std::move(client)));
   device_->AllocateAndStart(params, std::move(media_client));
 }
 
+void VideoCaptureDeviceProxyImpl::Stop() {
+  device_->StopAndDeAllocate();
+}
+
 // static
 media::VideoCaptureFormat VideoCaptureDeviceProxyImpl::ConvertFromMojoToMedia(
     mojom::VideoCaptureFormatPtr format) {
   media::VideoCaptureFormat result;
   result.pixel_format = ConvertFromMojoToMedia(format->pixel_format);
   result.pixel_storage = ConvertFromMojoToMedia(format->pixel_storage);
   result.frame_size.SetSize(format->frame_size.width(),
                             format->frame_size.height());
   result.frame_rate = format->frame_rate;
   return result;
@@ skipping 46 matching lines @@
     case mojom::PowerLineFrequency::HZ_50:
       return media::PowerLineFrequency::FREQUENCY_50HZ;
     case mojom::PowerLineFrequency::HZ_60:
       return media::PowerLineFrequency::FREQUENCY_60HZ;
   }
   NOTREACHED();
   return media::PowerLineFrequency::FREQUENCY_DEFAULT;
 }
 
 }  // namespace video_capture