[Chromoting] Introducing refcount-based life time management of the message loops in the service (daemon) and me2me host (network) processes.
This CL introduces AutoMessageLoop wrapper that provides control over life time of a message loop via scoped_refptr references. This scheme is useful in the cases when shutdown code has to run on a particular thread or when the OS requires resources (such as windows) to be freed before exiting a message loop.
The CL switches threads, owned by remoting::HostService, remoting::HostProcess and remoting::ChromotingHostContext, to refcount-based lifetime management. This change required updating tear-down sequences in remoting_me2me_host and the host plugin code.
BUG=134694
Review URL: https://chromiumcodereview.appspot.com/10829467
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@154827 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/remoting/host/chromoting_host_context.h b/remoting/host/chromoting_host_context.h
index 149444a..497b8e3 100644
--- a/remoting/host/chromoting_host_context.h
+++ b/remoting/host/chromoting_host_context.h
@@ -5,22 +5,17 @@
#ifndef REMOTING_HOST_CHROMOTING_HOST_CONTEXT_H_
#define REMOTING_HOST_CHROMOTING_HOST_CONTEXT_H_
-#include <string>
-
#include "base/gtest_prod_util.h"
#include "base/memory/ref_counted.h"
-#include "base/threading/platform_thread.h"
+#include "base/single_thread_task_runner.h"
#include "base/threading/thread.h"
-namespace base {
-class SingleThreadTaskRunner;
-} // namespace base
-
namespace net {
class URLRequestContextGetter;
} // namespace net
namespace remoting {
+class AutoThreadTaskRunner;
// A class that manages threads and running context for the chromoting host
// process. This class is virtual only for testing purposes (see below).
@@ -28,9 +23,11 @@
public:
// Create a context.
ChromotingHostContext(
- scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
+ scoped_refptr<AutoThreadTaskRunner> ui_task_runner);
virtual ~ChromotingHostContext();
+ void ReleaseTaskRunners();
+
// TODO(ajwong): Move the Start method out of this class. Then
// create a static factory for construction, and destruction. We
// should be able to remove the need for virtual functions below
@@ -38,61 +35,70 @@
// this API.
virtual bool Start();
- // Task runner for the thread that is used for the UI. In the NPAPI
- // plugin this corresponds to the main plugin thread.
- virtual base::SingleThreadTaskRunner* ui_task_runner();
+ // Task runner for the thread used for audio capture and encoding.
+ virtual base::SingleThreadTaskRunner* audio_task_runner();
// Task runner for the thread used by the ScreenRecorder to capture
// the screen.
virtual base::SingleThreadTaskRunner* capture_task_runner();
- // Task runner for the thread used to encode video streams.
- virtual base::SingleThreadTaskRunner* encode_task_runner();
-
- // Task runner for the thread used for audio capture and encoding.
- virtual base::SingleThreadTaskRunner* audio_task_runner();
-
- // Task runner for the thread used for network IO. This thread runs
- // a libjingle message loop, and is the only thread on which
- // libjingle code may be run.
- virtual base::SingleThreadTaskRunner* network_task_runner();
-
// Task runner for the thread that is used by the EventExecutor.
//
// TODO(sergeyu): Do we need a separate thread for EventExecutor?
// Can we use some other thread instead?
virtual base::SingleThreadTaskRunner* desktop_task_runner();
+ // Task runner for the thread used to encode video streams.
+ virtual base::SingleThreadTaskRunner* encode_task_runner();
+
// Task runner for the thread that is used for blocking file
// IO. This thread is used by the URLRequestContext to read proxy
// configuration and by NatConfig to read policy configs.
virtual base::SingleThreadTaskRunner* file_task_runner();
+ // Task runner for the thread used for network IO. This thread runs
+ // a libjingle message loop, and is the only thread on which
+ // libjingle code may be run.
+ virtual base::SingleThreadTaskRunner* network_task_runner();
+
+ // Task runner for the thread that is used for the UI. In the NPAPI
+ // plugin this corresponds to the main plugin thread.
+ virtual base::SingleThreadTaskRunner* ui_task_runner();
+
const scoped_refptr<net::URLRequestContextGetter>&
url_request_context_getter();
private:
FRIEND_TEST_ALL_PREFIXES(ChromotingHostContextTest, StartAndStop);
- // A thread that hosts all network operations.
- base::Thread network_thread_;
+ // A thread that hosts audio capture and encoding.
+ base::Thread audio_thread_;
// A thread that hosts screen capture.
base::Thread capture_thread_;
- // A thread that hosts all encode operations.
- base::Thread encode_thread_;
-
- // A thread that hosts audio capture and encoding.
- base::Thread audio_thread_;
-
// A thread that hosts input injection.
base::Thread desktop_thread_;
+ // A thread that hosts all encode operations.
+ base::Thread encode_thread_;
+
// Thread for blocking IO operations.
base::Thread file_thread_;
- scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
+ // A thread that hosts all network operations.
+ base::Thread network_thread_;
+
+ // Task runners wrapping the above threads. These should be declared after
+ // the corresponding threads to guarantee proper order of destruction.
+ scoped_refptr<base::SingleThreadTaskRunner> audio_task_runner_;
+ scoped_refptr<base::SingleThreadTaskRunner> capture_task_runner_;
+ scoped_refptr<base::SingleThreadTaskRunner> desktop_task_runner_;
+ scoped_refptr<base::SingleThreadTaskRunner> encode_task_runner_;
+ scoped_refptr<base::SingleThreadTaskRunner> file_task_runner_;
+ scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
+
+ scoped_refptr<AutoThreadTaskRunner> ui_task_runner_;
scoped_refptr<net::URLRequestContextGetter> url_request_context_getter_;
