Eliminate video capture thread in renderer

content/renderer/media/video_capture_impl.cc

 // Copyright (c) 2012 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/renderer/media/video_capture_impl.h"
 
 #include "base/bind.h"
 #include "base/stl_util.h"
 #include "content/child/child_process.h"
 #include "content/common/media/video_capture_messages.h"
@@ skipping 24 matching lines @@
 bool VideoCaptureImpl::CaptureStarted() {
   return state_ == VIDEO_CAPTURE_STATE_STARTED;
 }
 
 int VideoCaptureImpl::CaptureFrameRate() {
   return last_frame_format_.frame_rate;
 }
 
 VideoCaptureImpl::VideoCaptureImpl(
     const media::VideoCaptureSessionId session_id,
-    base::MessageLoopProxy* capture_message_loop_proxy,
     VideoCaptureMessageFilter* filter)
     : VideoCapture(),
       message_filter_(filter),
-      capture_message_loop_proxy_(capture_message_loop_proxy),
       io_message_loop_proxy_(ChildProcess::current()->io_message_loop_proxy()),
       device_id_(0),
       session_id_(session_id),
       suspended_(false),
       state_(VIDEO_CAPTURE_STATE_STOPPED),
       weak_this_factory_(this) {
   DCHECK(filter);
 }
 
 VideoCaptureImpl::~VideoCaptureImpl() {}
 
 void VideoCaptureImpl::Init() {
   if (!io_message_loop_proxy_->BelongsToCurrentThread()) {
     io_message_loop_proxy_->PostTask(FROM_HERE,
-        base::Bind(&VideoCaptureImpl::AddDelegateOnIOThread,
+        base::Bind(&VideoCaptureImpl::Init,
                    base::Unretained(this)));
-  } else {
-    AddDelegateOnIOThread();
+    return;
   }
+
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
+  message_filter_->AddDelegate(this);
 }
 
 void VideoCaptureImpl::DeInit(base::Closure task) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoDeInitOnCaptureThread,
-                 base::Unretained(this), task));
+  if (!io_message_loop_proxy_->BelongsToCurrentThread()) {
+    io_message_loop_proxy_->PostTask(FROM_HERE,
+        base::Bind(&VideoCaptureImpl::DeInit,
+                   base::Unretained(this),
+                   task));
+    return;
+  }
+
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
+  if (state_ == VIDEO_CAPTURE_STATE_STARTED)
+    Send(new VideoCaptureHostMsg_Stop(device_id_));
+  message_filter_->RemoveDelegate(this);
+  task.Run();
+}
+
+void VideoCaptureImpl::SuspendCapture(bool suspend) {
+  if (!io_message_loop_proxy_->BelongsToCurrentThread()) {
+    io_message_loop_proxy_->PostTask(FROM_HERE,
+        base::Bind(&VideoCaptureImpl::SuspendCapture,
+                   base::Unretained(this),
+                   suspend));
+    return;
+  }
+
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
+  suspended_ = suspend;
 }
 
 void VideoCaptureImpl::StartCapture(
     media::VideoCapture::EventHandler* handler,
     const media::VideoCaptureParams& params) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoStartCaptureOnCaptureThread,
-                 base::Unretained(this), handler, params));
-}
+  if (!io_message_loop_proxy_->BelongsToCurrentThread()) {
+    io_message_loop_proxy_->PostTask(FROM_HERE,
+        base::Bind(&VideoCaptureImpl::StartCapture,
+                   base::Unretained(this), handler, params));
+    return;
+  }
 
-void VideoCaptureImpl::StopCapture(media::VideoCapture::EventHandler* handler) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoStopCaptureOnCaptureThread,
-                 base::Unretained(this), handler));
-}
-
-void VideoCaptureImpl::OnBufferCreated(
-    base::SharedMemoryHandle handle,
-    int length, int buffer_id) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoBufferCreatedOnCaptureThread,
-                 base::Unretained(this), handle, length, buffer_id));
-}
-
-void VideoCaptureImpl::OnBufferDestroyed(int buffer_id) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoBufferDestroyedOnCaptureThread,
-                 base::Unretained(this), buffer_id));
-}
-
-void VideoCaptureImpl::OnBufferReceived(
-    int buffer_id,
-    base::Time timestamp,
-    const media::VideoCaptureFormat& format) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoBufferReceivedOnCaptureThread,
-                 base::Unretained(this), buffer_id, timestamp, format));
-}
-
-void VideoCaptureImpl::OnStateChanged(VideoCaptureState state) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoStateChangedOnCaptureThread,
-                 base::Unretained(this), state));
-}
-
-void VideoCaptureImpl::OnDelegateAdded(int32 device_id) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoDelegateAddedOnCaptureThread,
-                 base::Unretained(this), device_id));
-}
-
-void VideoCaptureImpl::SuspendCapture(bool suspend) {
-  capture_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::DoSuspendCaptureOnCaptureThread,
-                 base::Unretained(this), suspend));
-}
-
-void VideoCaptureImpl::DoDeInitOnCaptureThread(base::Closure task) {
-  if (state_ == VIDEO_CAPTURE_STATE_STARTED)
-    Send(new VideoCaptureHostMsg_Stop(device_id_));
-
-  io_message_loop_proxy_->PostTask(FROM_HERE,
-      base::Bind(&VideoCaptureImpl::RemoveDelegateOnIOThread,
-                 base::Unretained(this), task));
-}
-
-void VideoCaptureImpl::DoStartCaptureOnCaptureThread(
-    media::VideoCapture::EventHandler* handler,
-    const media::VideoCaptureParams& params) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
-
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
   if (state_ == VIDEO_CAPTURE_STATE_ERROR) {
     handler->OnError(this, 1);
     handler->OnRemoved(this);
   } else if ((clients_pending_on_filter_.find(handler) !=
               clients_pending_on_filter_.end()) ||
              (clients_pending_on_restart_.find(handler) !=
               clients_pending_on_restart_.end()) ||
              clients_.find(handler) != clients_.end() ) {
     // This client has started.
   } else if (!device_id_) {
@@ skipping 20 matching lines @@
             media::limits::kMaxFramesPerSecond;
       }
       DVLOG(1) << "StartCapture: starting with first resolution "
                << params_.requested_format.frame_size.ToString();
 
       StartCaptureInternal();
     }
   }
 }
 
-void VideoCaptureImpl::DoStopCaptureOnCaptureThread(
+void VideoCaptureImpl::StopCapture(
     media::VideoCapture::EventHandler* handler) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  if (!io_message_loop_proxy_->BelongsToCurrentThread()) {
+    io_message_loop_proxy_->PostTask(FROM_HERE,
+        base::Bind(&VideoCaptureImpl::StopCapture,
+                   base::Unretained(this), handler));
+    return;
+  }
+
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   // A handler can be in only one client list.
   // If this handler is in any client list, we can just remove it from
   // that client list and don't have to run the other following RemoveClient().
   RemoveClient(handler, &clients_pending_on_filter_) ||
   RemoveClient(handler, &clients_pending_on_restart_) ||
   RemoveClient(handler, &clients_);
 
   if (clients_.empty()) {
     DVLOG(1) << "StopCapture: No more client, stopping ...";
     StopDevice();
     client_buffers_.clear();
     weak_this_factory_.InvalidateWeakPtrs();
   }
 }
 
-void VideoCaptureImpl::DoBufferCreatedOnCaptureThread(
+void VideoCaptureImpl::OnBufferCreated(
     base::SharedMemoryHandle handle,
     int length, int buffer_id) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   // In case client calls StopCapture before the arrival of created buffer,
   // just close this buffer and return.
   if (state_ != VIDEO_CAPTURE_STATE_STARTED) {
     base::SharedMemory::CloseHandle(handle);
     return;
   }
 
   scoped_ptr<base::SharedMemory> shm(new base::SharedMemory(handle, false));
   if (!shm->Map(length)) {
-    DLOG(ERROR) << "DoBufferCreatedOnCaptureThread: Map() failed.";
+    DLOG(ERROR) << "SharedMemory::Map() failed.";

[Jói, 2013/12/27 13:34:35]

nit: "OnBufferCreated: Map failed." might give more context.

[Alpha Left Google, 2013/12/27 21:30:01]

Done.

     return;
   }
 
   bool inserted =
       client_buffers_.insert(std::make_pair(
                                  buffer_id,
                                  new ClientBuffer(shm.Pass(),
                                                   length))).second;
   DCHECK(inserted);
 }
 
-void VideoCaptureImpl::DoBufferDestroyedOnCaptureThread(int buffer_id) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+void VideoCaptureImpl::OnBufferDestroyed(int buffer_id) {
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   ClientBufferMap::iterator iter = client_buffers_.find(buffer_id);
   if (iter == client_buffers_.end())
     return;
 
   DCHECK(!iter->second || iter->second->HasOneRef())
       << "Instructed to delete buffer we are still using.";
   client_buffers_.erase(iter);
 }
 
-void VideoCaptureImpl::DoBufferReceivedOnCaptureThread(
+void VideoCaptureImpl::OnBufferReceived(
     int buffer_id,
     base::Time timestamp,
     const media::VideoCaptureFormat& format) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   if (state_ != VIDEO_CAPTURE_STATE_STARTED || suspended_) {
     Send(new VideoCaptureHostMsg_BufferReady(device_id_, buffer_id));
     return;
   }
 
   last_frame_format_ = format;
 
   ClientBufferMap::iterator iter = client_buffers_.find(buffer_id);
   DCHECK(iter != client_buffers_.end());
   scoped_refptr<ClientBuffer> buffer = iter->second;
   scoped_refptr<media::VideoFrame> frame =
       media::VideoFrame::WrapExternalPackedMemory(
           media::VideoFrame::I420,
           last_frame_format_.frame_size,
           gfx::Rect(last_frame_format_.frame_size),
           last_frame_format_.frame_size,
           reinterpret_cast<uint8*>(buffer->buffer->memory()),
           buffer->buffer_size,
           buffer->buffer->handle(),
           // TODO(sheu): convert VideoCaptureMessageFilter::Delegate to use
           // base::TimeTicks instead of base::Time.  http://crbug.com/249215
           timestamp - base::Time::UnixEpoch(),
           media::BindToLoop(
-              capture_message_loop_proxy_,
+              io_message_loop_proxy_,
               base::Bind(
-                  &VideoCaptureImpl::DoClientBufferFinishedOnCaptureThread,
+                  &VideoCaptureImpl::OnClientBufferFinished,
                   weak_this_factory_.GetWeakPtr(),
                   buffer_id,
                   buffer)));
 
   for (ClientInfo::iterator it = clients_.begin(); it != clients_.end(); ++it)
     it->first->OnFrameReady(this, frame);
 }
 
-void VideoCaptureImpl::DoClientBufferFinishedOnCaptureThread(
+void VideoCaptureImpl::OnClientBufferFinished(
     int buffer_id,
     const scoped_refptr<ClientBuffer>& buffer) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
   Send(new VideoCaptureHostMsg_BufferReady(device_id_, buffer_id));
 }
 
-void VideoCaptureImpl::DoStateChangedOnCaptureThread(VideoCaptureState state) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+void VideoCaptureImpl::OnStateChanged(VideoCaptureState state) {
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   switch (state) {
     case VIDEO_CAPTURE_STATE_STARTED:
       break;
     case VIDEO_CAPTURE_STATE_STOPPED:
       state_ = VIDEO_CAPTURE_STATE_STOPPED;
       DVLOG(1) << "OnStateChanged: stopped!, device_id = " << device_id_;
       client_buffers_.clear();
       weak_this_factory_.InvalidateWeakPtrs();
       if (!clients_.empty() || !clients_pending_on_restart_.empty())
@@ skipping 23 matching lines @@
         it->first->OnRemoved(this);
       }
       clients_.clear();
       state_ = VIDEO_CAPTURE_STATE_ENDED;
       break;
     default:
       break;
   }
 }
 
-void VideoCaptureImpl::DoDelegateAddedOnCaptureThread(int32 device_id) {
-  DVLOG(1) << "DoDelegateAdded: device_id " << device_id;
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+void VideoCaptureImpl::OnDelegateAdded(int32 device_id) {
+  DVLOG(1) << "OnDelegateAdded: device_id " << device_id;
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   device_id_ = device_id;
   for (ClientInfo::iterator it = clients_pending_on_filter_.begin();
        it != clients_pending_on_filter_.end(); ) {
     media::VideoCapture::EventHandler* handler = it->first;
     const media::VideoCaptureParams params = it->second;
     clients_pending_on_filter_.erase(it++);
     StartCapture(handler, params);
   }
 }
 
-void VideoCaptureImpl::DoSuspendCaptureOnCaptureThread(bool suspend) {
-  DVLOG(1) << "DoSuspendCapture: suspend " << (suspend ? "yes" : "no");
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
-
-  suspended_ = suspend;
-}
-
 void VideoCaptureImpl::StopDevice() {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
 
   if (state_ == VIDEO_CAPTURE_STATE_STARTED) {
     state_ = VIDEO_CAPTURE_STATE_STOPPING;
     Send(new VideoCaptureHostMsg_Stop(device_id_));
     params_.requested_format.frame_size.SetSize(0, 0);
   }
 }
 
 void VideoCaptureImpl::RestartCapture() {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
   DCHECK_EQ(state_, VIDEO_CAPTURE_STATE_STOPPED);
 
   int width = 0;
   int height = 0;
   for (ClientInfo::iterator it = clients_.begin();
        it != clients_.end(); ++it) {
     width = std::max(width, it->second.requested_format.frame_size.width());
     height = std::max(height, it->second.requested_format.frame_size.height());
   }
   for (ClientInfo::iterator it = clients_pending_on_restart_.begin();
        it != clients_pending_on_restart_.end(); ) {
     width = std::max(width, it->second.requested_format.frame_size.width());
     height = std::max(height, it->second.requested_format.frame_size.height());
     clients_[it->first] = it->second;
     clients_pending_on_restart_.erase(it++);
   }
   params_.requested_format.frame_size.SetSize(width, height);
   DVLOG(1) << "RestartCapture, "
            << params_.requested_format.frame_size.ToString();
   StartCaptureInternal();
 }
 
 void VideoCaptureImpl::StartCaptureInternal() {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
   DCHECK(device_id_);
 
   Send(new VideoCaptureHostMsg_Start(device_id_, session_id_, params_));
   state_ = VIDEO_CAPTURE_STATE_STARTED;
 }
 
-void VideoCaptureImpl::AddDelegateOnIOThread() {
-  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
-  message_filter_->AddDelegate(this);
-}
-
-void VideoCaptureImpl::RemoveDelegateOnIOThread(base::Closure task) {
-  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
-  message_filter_->RemoveDelegate(this);
-  capture_message_loop_proxy_->PostTask(FROM_HERE, task);
-}
-
 void VideoCaptureImpl::Send(IPC::Message* message) {
   io_message_loop_proxy_->PostTask(FROM_HERE,
       base::Bind(base::IgnoreResult(&VideoCaptureMessageFilter::Send),
                  message_filter_.get(), message));
 }
 
 bool VideoCaptureImpl::RemoveClient(
     media::VideoCapture::EventHandler* handler,
     ClientInfo* clients) {
-  DCHECK(capture_message_loop_proxy_->BelongsToCurrentThread());
+  DCHECK(io_message_loop_proxy_->BelongsToCurrentThread());
   bool found = false;
 
   ClientInfo::iterator it = clients->find(handler);
   if (it != clients->end()) {
     handler->OnStopped(this);
     handler->OnRemoved(this);
     clients->erase(it);
     found = true;
   }
   return found;
 }
 
 }  // namespace content