Dispatch IndexedDB IPC messages to worker threads

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/memory/ref_counted.h"
+#include "base/observer_list.h"
+#include "base/synchronization/lock.h"
+#include "base/threading/thread_local.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebWorkerRunLoop.h"
+
+#include <map>
+
+using WebKit::WebWorkerRunLoop;
+
+class WorkerTaskRunner : public base::RefCountedThreadSafe<WorkerTaskRunner> {
+ public:
+  WorkerTaskRunner();
+  ~WorkerTaskRunner();
+  // This could be changed to take a chromium closure that is then wrapped by
+  // this class.
+  void PostTask(int id, WebKit::WebWorkerRunLoop::Task* closure);
+  int CurrentWorkerId();
+
+  class Observer {
+   public:
+    virtual ~Observer() { }
+    virtual void onLoopRegistered() { }
+    virtual void onLoopUnregistered() { }
+  };
+  // 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.
+  void RemoveObserver(Observer* obs);
+
+ private:
+  friend class RendererWebKitPlatformSupportImpl;
+
+  typedef std::map<int, WebWorkerRunLoop> IDToLoopMap;
+
+  void RegisterCurrentWorkerLoop(const WebWorkerRunLoop& loop);
+  void UnRegisterCurrentWorkerLoop(const WebWorkerRunLoop& loop);
+
+  base::ThreadLocalPointer<std::pair<int, WebWorkerRunLoop> > current_tls_;
+
+  base::Lock lock_;
+  int id_sequence_;
+  IDToLoopMap loop_map_;
+
+  ObserverList<Observer> observer_list_;
+  base::Lock observer_lock_;
+};
+
+#endif  // CONTENT_COMMON_SOCKET_STREAM_H_