pjs/dom/workers/Workers.h

/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Web Workers.
 *
 * The Initial Developer of the Original Code is
 *   The Mozilla Foundation.
 * Portions created by the Initial Developer are Copyright (C) 2011
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Ben Turner <bent.mozilla@gmail.com> (Original Author)
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef mozilla_dom_workers_workers_h__
#define mozilla_dom_workers_workers_h__

#include "jspubtd.h"
#include "jsapi.h"
#include "nsISupportsImpl.h"
#include "mozilla/Mutex.h"

#define BEGIN_WORKERS_NAMESPACE \
  namespace mozilla { namespace dom { namespace workers {
#define END_WORKERS_NAMESPACE \
  } /* namespace workers */ } /* namespace dom */ } /* namespace mozilla */
#define USING_WORKERS_NAMESPACE \
  using namespace mozilla::dom::workers;

#define WORKERS_SHUTDOWN_TOPIC "web-workers-shutdown"

class nsPIDOMWindow;

BEGIN_WORKERS_NAMESPACE

class WorkerPrivate;

struct PrivatizableBase
{ };

#ifdef DEBUG
void
AssertIsOnMainThread();
#else
inline void
AssertIsOnMainThread()
{ }
#endif

// All of these are implemented in RuntimeService.cpp
JSBool
ResolveWorkerClasses(JSContext* aCx, JSObject* aObj, jsid aId, unsigned aFlags,
                     JSObject** aObjp);

void
CancelWorkersForWindow(JSContext* aCx, nsPIDOMWindow* aWindow);

void
SuspendWorkersForWindow(JSContext* aCx, nsPIDOMWindow* aWindow);

void
ResumeWorkersForWindow(JSContext* aCx, nsPIDOMWindow* aWindow);

class WorkerTask {
public:
    NS_INLINE_DECL_THREADSAFE_REFCOUNTING(WorkerTask)

    virtual ~WorkerTask() { }

    virtual bool RunTask(JSContext* aCx) = 0;
};

class WorkerCrossThreadDispatcher {
public:
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(WorkerCrossThreadDispatcher)

  WorkerCrossThreadDispatcher(WorkerPrivate* aPrivate) :
    mMutex("WorkerCrossThreadDispatcher"), mPrivate(aPrivate) {}
  void Forget()
  {
    mozilla::MutexAutoLock lock(mMutex);
    mPrivate = nsnull;
  }

  /**
   * Generically useful function for running a bit of C++ code on the worker
   * thread.
   */
  bool PostTask(WorkerTask* aTask);

protected:
  friend class WorkerPrivate;

  // Must be acquired *before* the WorkerPrivate's mutex, when they're both held.
  mozilla::Mutex mMutex;
  WorkerPrivate* mPrivate;
};

WorkerCrossThreadDispatcher*
GetWorkerCrossThreadDispatcher(JSContext* aCx, jsval aWorker);

// Random unique constant to facilitate JSPrincipal debugging
const uint32_t kJSPrincipalsDebugToken = 0x7e2df9d2;

END_WORKERS_NAMESPACE

#endif /* mozilla_dom_workers_workers_h__ */