widget/windows/nsUserIdleServiceWin.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:expandtab:shiftwidth=4:tabstop=4:
   3  */
   4 /* This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   7
   8 #ifndef nsUserIdleServiceWin_h__
   9 #define nsUserIdleServiceWin_h__
  10
  11 #include "nsUserIdleService.h"
  12 #include "mozilla/AppShutdown.h"
  13
  14 /* NOTE: Compare of GetTickCount() could overflow.  This corrects for
  15  * overflow situations.
  16  ***/
  17 #ifndef SAFE_COMPARE_EVEN_WITH_WRAPPING
  18 #  define SAFE_COMPARE_EVEN_WITH_WRAPPING(A, B) \
  19     (((int)((long)A - (long)B) & 0xFFFFFFFF))
  20 #endif
  21
  22 class nsUserIdleServiceWin : public nsUserIdleService {
  23  public:
  24   NS_INLINE_DECL_REFCOUNTING_INHERITED(nsUserIdleServiceWin, nsUserIdleService)
  25
  26   bool PollIdleTime(uint32_t* aIdleTime) override;
  27
  28   static already_AddRefed<nsUserIdleServiceWin> GetInstance() {
  29     RefPtr<nsUserIdleServiceWin> idleService =
  30         nsUserIdleService::GetInstance().downcast<nsUserIdleServiceWin>();
  31     if (!idleService) {
  32       // Avoid late instantiation or resurrection during shutdown.
  33       if (mozilla::AppShutdown::IsInOrBeyond(
  34               mozilla::ShutdownPhase::AppShutdownConfirmed)) {
  35         return nullptr;
  36       }
  37       idleService = new nsUserIdleServiceWin();
  38     }
  39
  40     return idleService.forget();
  41   }
  42
  43  protected:
  44   nsUserIdleServiceWin() {}
  45   virtual ~nsUserIdleServiceWin() {}
  46 };
  47
  48 #endif  // nsUserIdleServiceWin_h__