dom/base/MessagePort.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef mozilla_dom_MessagePort_h
   7 #define mozilla_dom_MessagePort_h
   8
   9 #include "mozilla/Attributes.h"
  10 #include "mozilla/DOMEventTargetHelper.h"
  11
  12 class nsPIDOMWindow;
  13
  14 namespace mozilla {
  15 namespace dom {
  16
  17 class DispatchEventRunnable;
  18 class PostMessageRunnable;
  19
  20 class MessagePortBase : public DOMEventTargetHelper
  21 {
  22 protected:
  23   explicit MessagePortBase(nsPIDOMWindow* aWindow);
  24   MessagePortBase();
  25
  26 public:
  27
  28   virtual void
  29   PostMessageMoz(JSContext* aCx, JS::Handle<JS::Value> aMessage,
  30                 const Optional<Sequence<JS::Value>>& aTransferable,
  31                 ErrorResult& aRv) = 0;
  32
  33   virtual void
  34   Start() = 0;
  35
  36   virtual void
  37   Close() = 0;
  38
  39   // The 'message' event handler has to call |Start()| method, so we
  40   // cannot use IMPL_EVENT_HANDLER macro here.
  41   virtual EventHandlerNonNull*
  42   GetOnmessage() = 0;
  43
  44   virtual void
  45   SetOnmessage(EventHandlerNonNull* aCallback) = 0;
  46
  47   // Duplicate this message port. This method is used by the Structured Clone
  48   // Algorithm and makes the new MessagePort active with the entangled
  49   // MessagePort of this object.
  50   virtual already_AddRefed<MessagePortBase>
  51   Clone() = 0;
  52 };
  53
  54 class MessagePort MOZ_FINAL : public MessagePortBase
  55 {
  56   friend class DispatchEventRunnable;
  57   friend class PostMessageRunnable;
  58
  59 public:
  60   NS_DECL_ISUPPORTS_INHERITED
  61   NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(MessagePort,
  62                                            DOMEventTargetHelper)
  63
  64   explicit MessagePort(nsPIDOMWindow* aWindow);
  65
  66   virtual JSObject*
  67   WrapObject(JSContext* aCx) MOZ_OVERRIDE;
  68
  69   virtual void
  70   PostMessageMoz(JSContext* aCx, JS::Handle<JS::Value> aMessage,
  71                  const Optional<Sequence<JS::Value>>& aTransferable,
  72                  ErrorResult& aRv) MOZ_OVERRIDE;
  73
  74   virtual void
  75   Start() MOZ_OVERRIDE;
  76
  77   virtual void
  78   Close() MOZ_OVERRIDE;
  79
  80   virtual EventHandlerNonNull*
  81   GetOnmessage() MOZ_OVERRIDE;
  82
  83   virtual void
  84   SetOnmessage(EventHandlerNonNull* aCallback) MOZ_OVERRIDE;
  85
  86   // Non WebIDL methods
  87
  88   // This method entangles this MessagePort with another one.
  89   // If it is already entangled, it's disentangled first and enatangle to the
  90   // new one.
  91   void
  92   Entangle(MessagePort* aMessagePort);
  93
  94   virtual already_AddRefed<MessagePortBase>
  95   Clone() MOZ_OVERRIDE;
  96
  97 private:
  98   ~MessagePort();
  99
 100   // Dispatch events from the Message Queue using a nsRunnable.
 101   void Dispatch();
 102
 103   nsRefPtr<DispatchEventRunnable> mDispatchRunnable;
 104
 105   nsRefPtr<MessagePort> mEntangledPort;
 106
 107   nsTArray<nsRefPtr<PostMessageRunnable> > mMessageQueue;
 108   bool mMessageQueueEnabled;
 109 };
 110
 111 } // namespace dom
 112 } // namespace mozilla
 113
 114 #endif // mozilla_dom_MessagePort_h