[Mojo Video Capture] Introduce abstraction BuildableVideoCaptureDevice

content/browser/renderer_host/media/in_process_buildable_video_capture_device.cc

+// Copyright 2017 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 "content/browser/renderer_host/media/in_process_buildable_video_capture_device.h"
+
+#include "base/metrics/histogram_macros.h"
+#include "base/strings/stringprintf.h"
+#include "content/browser/media/capture/desktop_capture_device_uma_types.h"
+#include "content/browser/media/capture/web_contents_video_capture_device.h"
+#include "content/browser/renderer_host/media/video_capture_controller.h"
+#include "content/browser/renderer_host/media/video_capture_gpu_jpeg_decoder.h"
+#include "content/browser/renderer_host/media/video_frame_receiver_on_io_thread.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/desktop_media_id.h"
+#include "content/public/common/media_stream_request.h"
+#include "media/base/bind_to_current_loop.h"
+#include "media/capture/video/video_capture_buffer_pool_impl.h"
+#include "media/capture/video/video_capture_buffer_tracker_factory_impl.h"
+#include "media/capture/video/video_capture_device_client.h"
+#include "media/capture/video/video_frame_receiver.h"
+
+#if defined(ENABLE_SCREEN_CAPTURE) && !defined(OS_ANDROID)
+#include "content/browser/media/capture/desktop_capture_device.h"
+#if defined(USE_AURA)
+#include "content/browser/media/capture/desktop_capture_device_aura.h"
+#endif
+#endif
+
+#if defined(ENABLE_SCREEN_CAPTURE) && defined(OS_ANDROID)
+#include "content/browser/media/capture/screen_capture_device_android.h"
+#endif
+
+namespace {
+
+class VideoFrameConsumerFeedbackObserverOnTaskRunner
+    : public media::VideoFrameConsumerFeedbackObserver {
+ public:
+  VideoFrameConsumerFeedbackObserverOnTaskRunner(
+      media::VideoFrameConsumerFeedbackObserver* observer,
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner)
+      : observer_(observer), task_runner_(std::move(task_runner)) {}
+
+  void OnUtilizationReport(int frame_feedback_id, double utilization) override {
+    task_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(
+            &media::VideoFrameConsumerFeedbackObserver::OnUtilizationReport,
+            base::Unretained(observer_), frame_feedback_id, utilization));
+  }
+
+ private:
+  media::VideoFrameConsumerFeedbackObserver* const observer_;
+  const scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+};
+
+std::unique_ptr<media::VideoCaptureJpegDecoder> CreateGpuJpegDecoder(
+    const media::VideoCaptureJpegDecoder::DecodeDoneCB& decode_done_cb) {
+  return base::MakeUnique<content::VideoCaptureGpuJpegDecoder>(decode_done_cb);
+}
+
+void StopAndReleaseDeviceOnDeviceThread(media::VideoCaptureDevice* device,
+                                        base::OnceClosure done_cb) {
+  SCOPED_UMA_HISTOGRAM_TIMER("Media.VideoCaptureManager.StopDeviceTime");
+  device->StopAndDeAllocate();
+  DVLOG(3) << "StopAndReleaseDeviceOnDeviceThread";
+  delete device;
+  std::move(done_cb).Run();

[miu, 2017/03/22 22:09:50]

Oh, I mentioned this in the other CL, but here is where it's introduced: Is it
necessary to std::move() here (and elsewhere, where done_cb.Run() is the last
thing a method does before returning)?

[chfremer, 2017/03/22 23:20:38]

Yes. The OnceCallback must be moved in order to invoke Run().
However, I just learned from mcasas@, that base::ResetAndReturn(&done_cb).Run()
now also works on OnceCallbacks (as of Feb 22nd).

+}
+
+// The maximum number of video frame buffers in-flight at any one time. This
+// value should be based on the logical capacity of the capture pipeline, and
+// not on hardware performance.  For example, tab capture requires more buffers
+// than webcam capture because the pipeline is longer (it includes read-backs
+// pending in the GPU pipeline).
+const int kMaxNumberOfBuffers = 3;
+// TODO(miu): The value for tab capture should be determined programmatically.
+// http://crbug.com/460318
+const int kMaxNumberOfBuffersForTabCapture = 10;
+
+}  // anonymous namespace
+
+namespace content {
+
+InProcessBuildableVideoCaptureDevice::InProcessBuildableVideoCaptureDevice(
+    scoped_refptr<base::SingleThreadTaskRunner> device_task_runner,
+    media::VideoCaptureDeviceFactory* device_factory)
+    : device_task_runner_(std::move(device_task_runner)),
+      device_factory_(device_factory) {}
+
+InProcessBuildableVideoCaptureDevice::~InProcessBuildableVideoCaptureDevice() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(!device_);
+}
+
+void InProcessBuildableVideoCaptureDevice::CreateAndStartDeviceAsync(
+    VideoCaptureController* controller,
+    const media::VideoCaptureParams& params,
+    Callbacks* callbacks,
+    base::OnceClosure done_cb) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  const int max_buffers = (controller->stream_type() == MEDIA_TAB_VIDEO_CAPTURE
+                               ? kMaxNumberOfBuffersForTabCapture
+                               : kMaxNumberOfBuffers);
+
+  auto device_client =
+      CreateDeviceClient(max_buffers, controller->GetWeakPtrForIOThread());
+
+  base::Closure start_capture_closure;
+  switch (controller->stream_type()) {
+    case MEDIA_DEVICE_VIDEO_CAPTURE: {
+      const media::VideoCaptureDeviceDescriptor* descriptor =
+          callbacks->LookupDeviceDescriptor(controller->device_id());
+      if (descriptor) {
+        controller->OnLog(
+            base::StringPrintf("Starting device: id: %s, name: %s, api: %s",
+                               descriptor->device_id.c_str(),
+                               descriptor->GetNameAndModel().c_str(),
+                               descriptor->GetCaptureApiTypeString()));
+
+        callbacks->WillStartDevice(descriptor->facing);
+
+        // Use of Unretained() is safe, because |context_reference| guarantees

[mcasas, 2017/03/22 22:43:16]

Seems like |context_reference| doesn't exist around here.
(Also in l. 145, 161).

[chfremer, 2017/03/22 23:20:38]

Done.

+        // that |this| stays alive.
+        ReceiveDeviceCallback after_start_capture_callback =
+            media::BindToCurrentLoop(base::Bind(
+                &InProcessBuildableVideoCaptureDevice::OnDeviceStarted,
+                base::Unretained(this), controller, callbacks,
+                base::Passed(&done_cb)));
+        start_capture_closure =
+            base::Bind(&InProcessBuildableVideoCaptureDevice::
+                           DoStartDeviceCaptureOnDeviceThread,
+                       base::Unretained(this), *descriptor, params,
+                       base::Passed(std::move(device_client)),
+                       std::move(after_start_capture_callback));
+      } else {
+        callbacks->OnDeviceStartFailed(controller);
+        std::move(done_cb).Run();
+        return;
+      }

[mcasas, 2017/03/22 22:43:16]

This probably predatesthis CL, but I suggest we move this else{}
upwards:

if (!descriptor) {
  callbacks->OnDeviceStartFailed(controller);
  base::ResetAndReturn(&done_cb)->Run();
  return;
}
// and here continue knowing that |descriptor| verifies, l.116.

[chfremer, 2017/03/22 23:20:38]

Done.

+      break;
+    }
+    case MEDIA_TAB_VIDEO_CAPTURE: {
+      // Use of Unretained() is safe, because |context_reference| guarantees

[miu, 2017/03/22 22:16:51]

s/context_reference/done_cb/

...and elsewhere...

[chfremer, 2017/03/22 23:20:38]

Done.

+      // that |this| stays alive.
+      ReceiveDeviceCallback after_start_capture_callback =
+          media::BindToCurrentLoop(
+              base::Bind(&InProcessBuildableVideoCaptureDevice::OnDeviceStarted,
+                         base::Unretained(this), controller, callbacks,
+                         base::Passed(&done_cb)));
+      start_capture_closure =
+          base::Bind(&InProcessBuildableVideoCaptureDevice::
+                         DoStartTabCaptureOnDeviceThread,
+                     base::Unretained(this), controller->device_id(), params,
+                     base::Passed(std::move(device_client)),
+                     std::move(after_start_capture_callback));
+      break;
+    }
+    case MEDIA_DESKTOP_VIDEO_CAPTURE: {
+      // Use of Unretained() is safe, because |context_reference| guarantees
+      // that |this| stays alive.
+      ReceiveDeviceCallback after_start_capture_callback =
+          media::BindToCurrentLoop(
+              base::Bind(&InProcessBuildableVideoCaptureDevice::OnDeviceStarted,
+                         base::Unretained(this), controller, callbacks,
+                         base::Passed(&done_cb)));
+      start_capture_closure =
+          base::Bind(&InProcessBuildableVideoCaptureDevice::
+                         DoStartDesktopCaptureOnDeviceThread,
+                     base::Unretained(this), controller->device_id(), params,
+                     base::Passed(std::move(device_client)),
+                     std::move(after_start_capture_callback));
+      break;
+    }
+    default: {
+      NOTIMPLEMENTED();
+      return;
+    }
+  }
+
+  device_task_runner_->PostTask(FROM_HERE, start_capture_closure);
+}
+
+void InProcessBuildableVideoCaptureDevice::ReleaseDeviceAsync(
+    VideoCaptureController* controller,
+    base::OnceClosure done_cb) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  controller->SetConsumerFeedbackObserver(nullptr);
+  if (!device_)
+    return;
+  media::VideoCaptureDevice* device_ptr = device_.release();
+
+  bool posting_task_succeeded = device_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&StopAndReleaseDeviceOnDeviceThread, device_ptr,
+                 base::Bind([](scoped_refptr<base::SingleThreadTaskRunner>) {},
+                            device_task_runner_)));
+  if (posting_task_succeeded == false) {
+    // Since posting to the task runner has failed, we attempt doing it on
+    // the calling thread instead.
+    StopAndReleaseDeviceOnDeviceThread(device_ptr, base::Bind([]() {}));
+  }
+  std::move(done_cb).Run();

[mcasas, 2017/03/22 22:43:16]

Same as in l.139, I'd say here
  base::ResetAndReturn(&done_cb)->Run();

because it's more explicit what you want to do.

Also to consider around all this methods and interfaces
is to use ScopedClosureRunner [1] which guarantees in
prose and code that the a given closure is either 
std::move()d or Run().  Keep it in mind for future 
refactorings ;)

[1]
https://cs.chromium.org/chromium/src/base/callback_helpers.h?type=cs&q=ResetA...,

[chfremer, 2017/03/22 23:20:38]

Thanks. I didn't know that base::ResetAndReturn() now supports OnceCallbacks (it
did not last time I tried, seems it was fixed recently). ScopedClosureRunner
currently does not support OnceCallbacks.

+}
+
+bool InProcessBuildableVideoCaptureDevice::IsDeviceAlive() const {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  return device_ != nullptr;
+}
+
+void InProcessBuildableVideoCaptureDevice::GetPhotoCapabilities(
+    media::VideoCaptureDevice::GetPhotoCapabilitiesCallback callback) const {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Unretained() is safe to use here because |device| would be null if it
+  // was scheduled for shutdown and destruction, and because this task is
+  // guaranteed to run before the task that destroys the |device|.
+  device_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&media::VideoCaptureDevice::GetPhotoCapabilities,
+                 base::Unretained(device_.get()), base::Passed(&callback)));
+}
+
+void InProcessBuildableVideoCaptureDevice::SetPhotoOptions(
+    media::mojom::PhotoSettingsPtr settings,
+    media::VideoCaptureDevice::SetPhotoOptionsCallback callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Unretained() is safe to use here because |device| would be null if it
+  // was scheduled for shutdown and destruction, and because this task is
+  // guaranteed to run before the task that destroys the |device|.
+  device_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&media::VideoCaptureDevice::SetPhotoOptions,
+                            base::Unretained(device_.get()),
+                            base::Passed(&settings), base::Passed(&callback)));
+}
+
+void InProcessBuildableVideoCaptureDevice::TakePhoto(
+    media::VideoCaptureDevice::TakePhotoCallback callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Unretained() is safe to use here because |device| would be null if it
+  // was scheduled for shutdown and destruction, and because this task is
+  // guaranteed to run before the task that destroys the |device|.
+  device_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&media::VideoCaptureDevice::TakePhoto,
+                 base::Unretained(device_.get()), base::Passed(&callback)));
+}
+
+void InProcessBuildableVideoCaptureDevice::MaybeSuspendDevice() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Unretained() is safe to use here because |device| would be null if it
+  // was scheduled for shutdown and destruction, and because this task is
+  // guaranteed to run before the task that destroys the |device|.
+  device_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&media::VideoCaptureDevice::MaybeSuspend,
+                            base::Unretained(device_.get())));
+}
+
+void InProcessBuildableVideoCaptureDevice::ResumeDevice() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Unretained() is safe to use here because |device| would be null if it
+  // was scheduled for shutdown and destruction, and because this task is
+  // guaranteed to run before the task that destroys the |device|.
+  device_task_runner_->PostTask(FROM_HERE,
+                                base::Bind(&media::VideoCaptureDevice::Resume,
+                                           base::Unretained(device_.get())));
+}
+
+void InProcessBuildableVideoCaptureDevice::RequestRefreshFrame() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Unretained() is safe to use here because |device| would be null if it
+  // was scheduled for shutdown and destruction, and because this task is
+  // guaranteed to run before the task that destroys the |device|.
+  device_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&media::VideoCaptureDevice::RequestRefreshFrame,
+                            base::Unretained(device_.get())));
+}
+
+void InProcessBuildableVideoCaptureDevice::SetDesktopCaptureWindowIdAsync(
+    gfx::NativeViewId window_id,
+    base::OnceClosure done_cb) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  // Post |device_| to the the device_task_runner_. This is safe since the
+  // device is destroyed on the device_task_runner_ and |context_reference|

[mcasas, 2017/03/22 22:43:16]

s/device_task_runner_/|device_task_runner_|/

|context_reference| ?

[chfremer, 2017/03/22 23:20:38]

Done.

+  // guarantees that |this| stays alive.
+  device_task_runner_->PostTask(
+      FROM_HERE, base::Bind(&InProcessBuildableVideoCaptureDevice::
+                                SetDesktopCaptureWindowIdOnDeviceThread,
+                            base::Unretained(this), device_.get(), window_id,
+                            base::Passed(&done_cb)));
+}
+
+std::unique_ptr<media::VideoCaptureDeviceClient>
+InProcessBuildableVideoCaptureDevice::CreateDeviceClient(
+    int buffer_pool_max_buffer_count,
+    base::WeakPtr<media::VideoFrameReceiver> receiver) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  scoped_refptr<media::VideoCaptureBufferPool> buffer_pool_ =
+      new media::VideoCaptureBufferPoolImpl(
+          base::MakeUnique<media::VideoCaptureBufferTrackerFactoryImpl>(),
+          buffer_pool_max_buffer_count);
+
+  return base::MakeUnique<media::VideoCaptureDeviceClient>(
+      base::MakeUnique<VideoFrameReceiverOnIOThread>(receiver), buffer_pool_,
+      base::Bind(&CreateGpuJpegDecoder,
+                 base::Bind(&media::VideoFrameReceiver::OnFrameReadyInBuffer,
+                            receiver)));
+}
+
+void InProcessBuildableVideoCaptureDevice::OnDeviceStarted(
+    VideoCaptureController* controller,
+    Callbacks* callbacks,
+    base::OnceClosure done_cb,
+    std::unique_ptr<media::VideoCaptureDevice> device) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (!device) {
+    callbacks->OnDeviceStartFailed(controller);
+    std::move(done_cb).Run();
+    return;
+  }
+  // Passing raw pointer |device.get()| to the controller is safe,
+  // because we take ownership of |device| and we call
+  // controller->SetConsumerFeedbackObserver(nullptr) before releasing |device|.
+  controller->SetConsumerFeedbackObserver(
+      base::MakeUnique<VideoFrameConsumerFeedbackObserverOnTaskRunner>(
+          device.get(), device_task_runner_));
+  device_ = std::move(device);
+  callbacks->DidStartDevice(controller);
+  std::move(done_cb).Run();
+}
+
+void InProcessBuildableVideoCaptureDevice::DoStartDeviceCaptureOnDeviceThread(
+    const media::VideoCaptureDeviceDescriptor& descriptor,
+    const media::VideoCaptureParams& params,
+    std::unique_ptr<media::VideoCaptureDeviceClient> device_client,
+    ReceiveDeviceCallback result_callback) {
+  SCOPED_UMA_HISTOGRAM_TIMER("Media.VideoCaptureManager.StartDeviceTime");
+  DCHECK(device_task_runner_->BelongsToCurrentThread());
+
+  std::unique_ptr<media::VideoCaptureDevice> video_capture_device =
+      device_factory_->CreateDevice(descriptor);
+
+  if (!video_capture_device) {
+    result_callback.Run(nullptr);
+    return;
+  }
+
+  video_capture_device->AllocateAndStart(params, std::move(device_client));
+  result_callback.Run(std::move(video_capture_device));
+}
+
+void InProcessBuildableVideoCaptureDevice::DoStartTabCaptureOnDeviceThread(
+    const std::string& id,
+    const media::VideoCaptureParams& params,
+    std::unique_ptr<media::VideoCaptureDeviceClient> device_client,
+    ReceiveDeviceCallback result_callback) {
+  SCOPED_UMA_HISTOGRAM_TIMER("Media.VideoCaptureManager.StartDeviceTime");
+  DCHECK(device_task_runner_->BelongsToCurrentThread());
+
+  std::unique_ptr<media::VideoCaptureDevice> video_capture_device;
+#if defined(OS_LINUX) || defined(OS_MACOSX) || defined(OS_WIN)
+  video_capture_device = WebContentsVideoCaptureDevice::Create(id);
+#endif
+
+  if (!video_capture_device) {
+    result_callback.Run(nullptr);
+    return;
+  }
+
+  video_capture_device->AllocateAndStart(params, std::move(device_client));
+  result_callback.Run(std::move(video_capture_device));
+}
+
+void InProcessBuildableVideoCaptureDevice::DoStartDesktopCaptureOnDeviceThread(
+    const std::string& id,
+    const media::VideoCaptureParams& params,
+    std::unique_ptr<media::VideoCaptureDeviceClient> device_client,
+    ReceiveDeviceCallback result_callback) {
+  SCOPED_UMA_HISTOGRAM_TIMER("Media.VideoCaptureManager.StartDeviceTime");
+  DCHECK(device_task_runner_->BelongsToCurrentThread());
+
+  std::unique_ptr<media::VideoCaptureDevice> video_capture_device;
+#if defined(ENABLE_SCREEN_CAPTURE)
+  DesktopMediaID desktop_id = DesktopMediaID::Parse(id);
+  if (desktop_id.is_null()) {
+    DLOG(ERROR) << "Desktop media ID is null";
+    result_callback.Run(nullptr);
+    return;
+  }
+
+  if (desktop_id.type == DesktopMediaID::TYPE_WEB_CONTENTS) {
+#if defined(OS_LINUX) || defined(OS_MACOSX) || defined(OS_WIN)
+    video_capture_device = WebContentsVideoCaptureDevice::Create(id);
+    IncrementDesktopCaptureCounter(TAB_VIDEO_CAPTURER_CREATED);
+    if (desktop_id.audio_share) {
+      IncrementDesktopCaptureCounter(TAB_VIDEO_CAPTURER_CREATED_WITH_AUDIO);
+    } else {
+      IncrementDesktopCaptureCounter(TAB_VIDEO_CAPTURER_CREATED_WITHOUT_AUDIO);
+    }

[mcasas, 2017/03/22 22:43:16]

nit: no {} for one line bodies.  Probably this predates you,
but can't harm.

[chfremer, 2017/03/22 23:20:38]

Done.

+#endif
+  } else {
+#if defined(OS_ANDROID)
+    video_capture_device = base::MakeUnique<ScreenCaptureDeviceAndroid>();
+#else
+#if defined(USE_AURA)
+    video_capture_device = DesktopCaptureDeviceAura::Create(desktop_id);
+#endif  // defined(USE_AURA)
+#if BUILDFLAG(ENABLE_WEBRTC)
+    if (!video_capture_device)
+      video_capture_device = DesktopCaptureDevice::Create(desktop_id);
+#endif  // BUILDFLAG(ENABLE_WEBRTC)
+#endif  // defined (OS_ANDROID)
+  }
+#endif  // defined(ENABLE_SCREEN_CAPTURE)
+
+  if (!video_capture_device) {
+    result_callback.Run(nullptr);
+    return;
+  }
+
+  video_capture_device->AllocateAndStart(params, std::move(device_client));
+  result_callback.Run(std::move(video_capture_device));
+}
+
+void InProcessBuildableVideoCaptureDevice::
+    SetDesktopCaptureWindowIdOnDeviceThread(media::VideoCaptureDevice* device,
+                                            gfx::NativeViewId window_id,
+                                            base::OnceClosure done_cb) {
+  DCHECK(device_task_runner_->BelongsToCurrentThread());
+#if defined(ENABLE_SCREEN_CAPTURE) && BUILDFLAG(ENABLE_WEBRTC) && \
+    !defined(OS_ANDROID)
+  DesktopCaptureDevice* desktop_device =
+      static_cast<DesktopCaptureDevice*>(device);
+  desktop_device->SetNotificationWindowId(window_id);
+  VLOG(2) << "Screen capture notification window passed on device thread.";
+#endif
+  std::move(done_cb).Run();
+}
+
+}  // namespace content