Track webcore worker message loops in chromium.

content/common/worker_task_runner.h

+// Copyright (c) 2011 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.
+
+#ifndef CONTENT_COMMON_WORKER_TASK_RUNNER_H_
+#define CONTENT_COMMON_WORKER_TASK_RUNNER_H_
+#pragma once
+
+#include "base/callback_forward.h"
+#include "base/synchronization/lock.h"
+#include "base/threading/thread_local.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebWorkerRunLoop.h"
+
+#include <map>

[darin (slow to review), 2011/12/08 22:41:21]

nit: these are supposed to go above the other includes:
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Names_and_Orde...

[dgrogan, 2011/12/09 03:20:41]

Done.

+#include <set>
+
+class WorkerTaskRunner {
+ public:
+  WorkerTaskRunner();
+
+  void PostTask(int id, const base::Closure& task);
+  int CurrentWorkerId();
+  static WorkerTaskRunner* Instance();
+
+  class Observer {
+   public:
+    virtual ~Observer() {}
+    virtual void OnWorkerRunLoopStarted();
+    virtual void OnWorkerRunLoopStopped();

[michaeln, 2011/12/09 00:43:32]

pure virtual?

[dgrogan, 2011/12/09 03:20:41]

I gave them a default empty implementation.

+  };
+  // Can be called on any thread.  The notifications will be called on the
+  // worker thread in question.
+  void AddObserver(Observer* obs);
+  // Unlike most Observerlists, observers can't remove themselves from this one
+  // during a notification.  Deadlock may result.
+  // Returns number of observers removed.

[michaeln, 2011/12/08 03:10:47]

why the return value?

[dgrogan, 2011/12/09 03:20:41]

Mostly because it's available and could feasibly be useful to some callers.  I
clarified the comment.

+  int RemoveObserver(Observer* obs);
+
+ private:
+  friend class RendererWebKitPlatformSupportImpl;
+
+  typedef std::map<int, WebKit::WebWorkerRunLoop> IDToLoopMap;
+
+  ~WorkerTaskRunner();
+  void OnWorkerRunLoopStarted(const WebKit::WebWorkerRunLoop& loop);
+  void OnWorkerRunLoopStopped(const WebKit::WebWorkerRunLoop& loop);
+
+  base::ThreadLocalPointer<std::pair<int, WebKit::WebWorkerRunLoop> >
+      current_tls_;
+
+  base::Lock lock_;
+  int id_sequence_;
+  IDToLoopMap loop_map_;
+
+  typedef std::set<Observer*> ObserverList;
+  ObserverList observer_list_;
+  base::Lock observer_lock_;
+};
+
+#endif  // CONTENT_COMMON_SOCKET_STREAM_H_