dom/power/WakeLock.h

   1 /* -*- Mode: C++; tab-width: 40; 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 file,
   4  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef mozilla_dom_power_WakeLock_h
   7 #define mozilla_dom_power_WakeLock_h
   8
   9 #include "nsCOMPtr.h"
  10 #include "nsIDOMEventListener.h"
  11 #include "nsIObserver.h"
  12 #include "nsString.h"
  13 #include "nsWeakReference.h"
  14 #include "nsWrapperCache.h"
  15 #include "mozilla/ErrorResult.h"
  16
  17 class nsIDOMWindow;
  18
  19 namespace mozilla {
  20 namespace dom {
  21
  22 class ContentParent;
  23
  24 class WakeLock MOZ_FINAL
  25   : public nsIDOMEventListener
  26   , public nsWrapperCache
  27   , public nsIObserver
  28   , public nsSupportsWeakReference
  29 {
  30 public:
  31   NS_DECL_NSIDOMEVENTLISTENER
  32   NS_DECL_NSIOBSERVER
  33
  34   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  35   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(WakeLock, nsIDOMEventListener)
  36
  37   // Note: WakeLock lives for the lifetime of the document in order to avoid
  38   // exposing GC behavior to pages. This means that
  39   // |var foo = navigator.requestWakeLock('cpu'); foo = null;|
  40   // doesn't unlock the 'cpu' resource.
  41
  42   WakeLock();
  43
  44   // Initialize this wake lock on behalf of the given window.  Null windows are
  45   // allowed; a lock without an associated window is always considered
  46   // invisible.
  47   nsresult Init(const nsAString &aTopic, nsIDOMWindow* aWindow);
  48
  49   // Initialize this wake lock on behalf of the given process.  If the process
  50   // dies, the lock is released.  A wake lock initialized via this method is
  51   // always considered visible.
  52   nsresult Init(const nsAString &aTopic, ContentParent* aContentParent);
  53
  54   // WebIDL methods
  55
  56   nsISupports* GetParentObject() const;
  57
  58   virtual JSObject*
  59   WrapObject(JSContext* aCx) MOZ_OVERRIDE;
  60
  61   void GetTopic(nsAString& aTopic);
  62
  63   void Unlock(ErrorResult& aRv);
  64
  65 private:
  66   virtual ~WakeLock();
  67
  68   void     DoUnlock();
  69   void     DoLock();
  70   void     AttachEventListener();
  71   void     DetachEventListener();
  72
  73   bool      mLocked;
  74   bool      mHidden;
  75
  76   // The ID of the ContentParent on behalf of whom we acquired this lock, or
  77   // CONTENT_PROCESS_UNKNOWN_ID if this lock was acquired on behalf of the
  78   // current process.
  79   uint64_t  mContentParentID;
  80   nsString  mTopic;
  81
  82   // window that this was created for.  Weak reference.
  83   nsWeakPtr mWindow;
  84 };
  85
  86 } // namespace dom
  87 } // namespace mozilla
  88
  89 #endif // mozilla_dom_power_WakeLock_h