layout/base/PaintTracker.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef mozilla_PaintTracker_h
   6 #define mozilla_PaintTracker_h
   7
   8 #include "mozilla/Attributes.h"
   9 #include "nsDebug.h"
  10
  11 namespace mozilla {
  12
  13 class MOZ_STACK_CLASS PaintTracker
  14 {
  15 public:
  16   PaintTracker() {
  17     ++gPaintTracker;
  18   }
  19   ~PaintTracker() {
  20     NS_ASSERTION(gPaintTracker > 0, "Mismatched constructor/destructor");
  21     --gPaintTracker;
  22   }
  23
  24   static bool IsPainting() {
  25     return !!gPaintTracker;
  26   }
  27
  28 private:
  29   static int gPaintTracker;
  30 };
  31
  32 } // namespace mozilla
  33
  34 #endif // mozilla_PaintTracker_h