dom/workers/WorkerThread.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_workers_WorkerThread_h__
   8 #define mozilla_dom_workers_WorkerThread_h__
   9
  10 #include "mozilla/AlreadyAddRefed.h"
  11 #include "mozilla/CondVar.h"
  12 #include "mozilla/Mutex.h"
  13 #include "mozilla/RefPtr.h"
  14 #include "mozilla/dom/SafeRefPtr.h"
  15 #include "nsISupports.h"
  16 #include "nsThread.h"
  17 #include "nscore.h"
  18
  19 class nsIRunnable;
  20
  21 namespace mozilla {
  22 class Runnable;
  23
  24 namespace dom {
  25
  26 class WorkerRunnable;
  27 class WorkerPrivate;
  28 template <class>
  29 class WorkerPrivateParent;
  30
  31 namespace workerinternals {
  32 class RuntimeService;
  33 }
  34
  35 // This class lets us restrict the public methods that can be called on
  36 // WorkerThread to RuntimeService and WorkerPrivate without letting them gain
  37 // full access to private methods (as would happen if they were simply friends).
  38 class WorkerThreadFriendKey {
  39   friend class workerinternals::RuntimeService;
  40   friend class WorkerPrivate;
  41   friend class WorkerPrivateParent<WorkerPrivate>;
  42
  43   WorkerThreadFriendKey();
  44   ~WorkerThreadFriendKey();
  45 };
  46
  47 class WorkerThread final : public nsThread {
  48   class Observer;
  49
  50   Mutex mLock MOZ_UNANNOTATED;
  51   CondVar mWorkerPrivateCondVar;
  52
  53   // Protected by nsThread::mLock.
  54   WorkerPrivate* mWorkerPrivate;
  55
  56   // Only touched on the target thread.
  57   RefPtr<Observer> mObserver;
  58
  59   // Protected by nsThread::mLock and waited on with mWorkerPrivateCondVar.
  60   uint32_t mOtherThreadsDispatchingViaEventTarget;
  61
  62 #ifdef DEBUG
  63   // Protected by nsThread::mLock.
  64   bool mAcceptingNonWorkerRunnables;
  65 #endif
  66
  67   // Using this struct we restrict access to the constructor while still being
  68   // able to use MakeSafeRefPtr.
  69   struct ConstructorKey {};
  70
  71  public:
  72   explicit WorkerThread(ConstructorKey);
  73
  74   static SafeRefPtr<WorkerThread> Create(const WorkerThreadFriendKey& aKey);
  75
  76   void SetWorker(const WorkerThreadFriendKey& aKey,
  77                  WorkerPrivate* aWorkerPrivate);
  78
  79   nsresult DispatchPrimaryRunnable(const WorkerThreadFriendKey& aKey,
  80                                    already_AddRefed<nsIRunnable> aRunnable);
  81
  82   nsresult DispatchAnyThread(const WorkerThreadFriendKey& aKey,
  83                              already_AddRefed<WorkerRunnable> aWorkerRunnable);
  84
  85   uint32_t RecursionDepth(const WorkerThreadFriendKey& aKey) const;
  86
  87   // Override HasPendingEvents to allow HasPendingEvents could be accessed by
  88   // the parent thread. WorkerPrivate::IsEligibleForCC calls this method on the
  89   // parent thread to check if there is any pending events on the worker thread.
  90   NS_IMETHOD HasPendingEvents(bool* aHasPendingEvents) override;
  91
  92   NS_INLINE_DECL_REFCOUNTING_INHERITED(WorkerThread, nsThread)
  93
  94  private:
  95   ~WorkerThread();
  96
  97   // This should only be called by consumers that have an
  98   // nsIEventTarget/nsIThread pointer.
  99   NS_IMETHOD
 100   Dispatch(already_AddRefed<nsIRunnable> aRunnable, uint32_t aFlags) override;
 101
 102   NS_IMETHOD
 103   DispatchFromScript(nsIRunnable* aRunnable, uint32_t aFlags) override;
 104
 105   NS_IMETHOD
 106   DelayedDispatch(already_AddRefed<nsIRunnable>, uint32_t) override;
 107 };
 108
 109 }  // namespace dom
 110 }  // namespace mozilla
 111
 112 #endif  // mozilla_dom_workers_WorkerThread_h__