DesktopSessionAgent now hosts the video capturer and provides necessary plumbing to drive it via an…

remoting/host/desktop_session_agent.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 "remoting/host/desktop_session_agent.h"
 
 #include "base/logging.h"
 #include "ipc/ipc_channel_proxy.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_message_macros.h"
 #include "remoting/base/auto_thread_task_runner.h"
+#include "remoting/base/capture_data.h"
 #include "remoting/host/chromoting_messages.h"
+#include "remoting/proto/control.pb.h"
+#include "third_party/skia/include/core/SkRegion.h"
 
 namespace remoting {
 
 DesktopSessionAgent::~DesktopSessionAgent() {
-  DCHECK(caller_task_runner()->BelongsToCurrentThread());
+  DCHECK(!video_capturer_);
 }
 
 bool DesktopSessionAgent::OnMessageReceived(const IPC::Message& message) {
   DCHECK(caller_task_runner()->BelongsToCurrentThread());
 
-  NOTIMPLEMENTED();
-  return false;
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(DesktopSessionAgent, message)
+    IPC_MESSAGE_HANDLER(ChromotingNetworkDesktopMsg_CaptureFrame,
+                        OnCaptureFrame)
+    IPC_MESSAGE_HANDLER(ChromotingNetworkDesktopMsg_InvalidateRegion,
+                        OnInvalidateRegion)
+    IPC_MESSAGE_HANDLER(ChromotingNetworkDesktopMsg_SharedBufferCreated,
+                        OnSharedBufferCreated)
+  IPC_END_MESSAGE_MAP()
+  return handled;
 }
 
 void DesktopSessionAgent::OnChannelConnected(int32 peer_pid) {
   DCHECK(caller_task_runner()->BelongsToCurrentThread());
 
   VLOG(1) << "IPC: desktop <- network (" << peer_pid << ")";
-
-  NOTIMPLEMENTED();
 }
 
 void DesktopSessionAgent::OnChannelError() {
   DCHECK(caller_task_runner()->BelongsToCurrentThread());
 
   // Make sure the channel is closed.
   network_channel_.reset();
 
-  // Notify the caller that |this| can be destroyed now.
-  done_task_.Run();
+  // Notify the caller that the channel has been disconnected.
+  disconnected_task_.Run();
 }
 
-bool DesktopSessionAgent::Start(const base::Closure& done_task,
+scoped_refptr<SharedBuffer> DesktopSessionAgent::CreateSharedBuffer(
+    uint32 size) {
+  DCHECK(video_capture_task_runner()->BelongsToCurrentThread());
+
+  scoped_refptr<SharedBuffer> buffer = new SharedBuffer(size);
+  if (buffer->ptr() != NULL) {
+    buffer->set_id(next_shared_buffer_id_);
+    shared_buffers_.push_back(buffer);
+
+    // |next_shared_buffer_id_| starts from 1 and incrementing it by 2 makes
+    // sure it is always odd and therefore zero is never used as a valid buffer
+    // ID.
+    //
+    // It is very unlikely (though theoretically possible) to allocate the same
+    // ID for two different buffers due to integer overflow. It should take
+    // about a year of allocating 100 new buffers every second. Practically
+    // speaking it never happens.
+    next_shared_buffer_id_ += 2;

[Cris Neckar, 2012/11/26 22:57:53]

Nit: If this is already a time consuming operation and this should never happen
we might as well put a check here and CRASH() if it ever does occur.

[alexeypa (please no reviews), 2012/11/26 23:47:13]

If we ever reallocate buffers we tend to reallocate all of them, so in wast
majority of cases ID overflow is harmless. I think CHECKing would be an
overkill.

+
+    SendToNetwork(new ChromotingDesktopNetworkMsg_CreateSharedBuffer(
+        buffer->id(), buffer->handle(), buffer->size()));
+  }
+
+  return buffer;
+}
+
+void DesktopSessionAgent::ReleaseSharedBuffer(
+    scoped_refptr<SharedBuffer> buffer) {
+  DCHECK(video_capture_task_runner()->BelongsToCurrentThread());
+  DCHECK(buffer->id() != 0);
+
+  SendToNetwork(
+      new ChromotingDesktopNetworkMsg_ReleaseSharedBuffer(buffer->id()));
+}
+
+void DesktopSessionAgent::OnCaptureCompleted(
+    scoped_refptr<CaptureData> capture_data) {
+  DCHECK(video_capture_task_runner()->BelongsToCurrentThread());
+
+  // Serialize CaptureData
+  SerializedCapturedData serialized_data;
+  serialized_data.shared_buffer_id = capture_data->shared_buffer()->id();
+  serialized_data.dimensions = capture_data->size();
+  serialized_data.pixel_format = capture_data->pixel_format();
+  serialized_data.capture_time_ms = capture_data->capture_time_ms();
+  serialized_data.client_sequence_number =
+      capture_data->client_sequence_number();
+  serialized_data.dpi = capture_data->dpi();
+  for (SkRegion::Iterator i(capture_data->dirty_region()); !i.done(); i.next())
+    serialized_data.dirty_region.push_back(i.rect());
+
+  SendToNetwork(
+      new ChromotingDesktopNetworkMsg_CaptureCompleted(serialized_data));
+}
+
+void DesktopSessionAgent::OnCursorShapeChanged(
+    scoped_ptr<protocol::CursorShapeInfo> cursor_shape) {
+  DCHECK(video_capture_task_runner()->BelongsToCurrentThread());
+
+  NOTIMPLEMENTED();
+}
+
+bool DesktopSessionAgent::Start(const base::Closure& disconnected_task,
                                 IPC::PlatformFileForTransit* desktop_pipe_out) {
   DCHECK(caller_task_runner()->BelongsToCurrentThread());
 
-  done_task_ = done_task;
-  return DoCreateNetworkChannel(desktop_pipe_out, &network_channel_);
+  disconnected_task_ = disconnected_task;
+  if (!CreateChannelForNetworkProcess(desktop_pipe_out, &network_channel_))
+    return false;
+
+  // Start the video capturer.
+  video_capture_task_runner()->PostTask(
+      FROM_HERE, base::Bind(&DesktopSessionAgent::StartVideoCapturer, this));
+  return true;
+}
+
+void DesktopSessionAgent::Stop() {
+  DCHECK(caller_task_runner()->BelongsToCurrentThread());
+
+  // Stop the video capturer.
+  video_capture_task_runner()->PostTask(
+      FROM_HERE, base::Bind(&DesktopSessionAgent::StopVideoCapturer, this));
+}
+
+void DesktopSessionAgent::OnCaptureFrame() {
+  if (!video_capture_task_runner()->BelongsToCurrentThread()) {
+    video_capture_task_runner()->PostTask(
+        FROM_HERE,
+        base::Bind(&DesktopSessionAgent::OnCaptureFrame, this));
+    return;
+  }
+
+  // VideoFrameCapturer supports a very few (currently 2) outstanding capture
+  // requests. The requests are serialized on |video_capture_task_runner()| task
+  // runner. If the client issues more requests, pixel data in captured farmes
+  // will likely be corrupted but stability of VideoFrameCapturer will not be
+  // affected.
+  video_capturer_->CaptureInvalidRegion();
+}
+
+void DesktopSessionAgent::OnInvalidateRegion(
+    const std::vector<SkIRect>& invalid_rects) {
+  if (!video_capture_task_runner()->BelongsToCurrentThread()) {
+    video_capture_task_runner()->PostTask(
+        FROM_HERE,
+        base::Bind(&DesktopSessionAgent::OnInvalidateRegion, this,
+                   invalid_rects));
+    return;
+  }
+
+  SkIRect bounds = SkIRect::MakeSize(video_capturer_->size_most_recent());
+
+  // Convert |invalid_rects| into a region.
+  SkRegion invalid_region;
+  for (std::vector<SkIRect>::const_iterator i = invalid_rects.begin();
+      i != invalid_rects.end(); ++i) {
+    // Validate each rectange and clip it to the frame bounds. If the rectangle
+    // is not valid it is ignored.
+    SkIRect rect;
+    if (rect.intersect(*i, bounds)) {
+      invalid_region.op(rect, SkRegion::kUnion_Op);
+    }
+  }
+
+  video_capturer_->InvalidateRegion(invalid_region);
+}
+
+void DesktopSessionAgent::OnSharedBufferCreated(int id) {
+  if (!video_capture_task_runner()->BelongsToCurrentThread()) {
+    video_capture_task_runner()->PostTask(
+        FROM_HERE,
+        base::Bind(&DesktopSessionAgent::OnSharedBufferCreated, this, id));
+    return;
+  }
+
+  // Drop the cached reference to the buffer.
+  SharedBuffers::iterator i = shared_buffers_.begin();
+  for (; i != shared_buffers_.end(); ++i) {
+    if ((*i)->id() == id) {
+      shared_buffers_.erase(i);
+      break;
+    }
+  }
+}
+
+void DesktopSessionAgent::SendToNetwork(IPC::Message* message) {
+  if (!caller_task_runner()->BelongsToCurrentThread()) {
+    caller_task_runner()->PostTask(
+        FROM_HERE,
+        base::Bind(&DesktopSessionAgent::SendToNetwork, this, message));
+    return;
+  }
+
+  if (network_channel_) {
+    network_channel_->Send(message);
+  } else {
+    delete message;
+  }
+}
+
+void DesktopSessionAgent::StartVideoCapturer() {
+  DCHECK(video_capture_task_runner()->BelongsToCurrentThread());
+
+  video_capturer_ = VideoFrameCapturer::CreateWithFactory(this);
+  video_capturer_->Start(this);
+}
+
+void DesktopSessionAgent::StopVideoCapturer() {
+  DCHECK(video_capture_task_runner()->BelongsToCurrentThread());
+
+  if (video_capturer_) {
+    video_capturer_->Stop();
+    video_capturer_.reset();
+  }
+
+  // Free any shared buffers left.
+  shared_buffers_.clear();
 }
 
 DesktopSessionAgent::DesktopSessionAgent(
     scoped_refptr<AutoThreadTaskRunner> caller_task_runner,
-    scoped_refptr<AutoThreadTaskRunner> io_task_runner)
+    scoped_refptr<AutoThreadTaskRunner> io_task_runner,
+    scoped_refptr<AutoThreadTaskRunner> video_capture_task_runner)
     : caller_task_runner_(caller_task_runner),
-      io_task_runner_(io_task_runner) {
+      io_task_runner_(io_task_runner),
+      video_capture_task_runner_(video_capture_task_runner),
+      next_shared_buffer_id_(1) {
   DCHECK(caller_task_runner_->BelongsToCurrentThread());
 }
 
 }  // namespace remoting