workspace/libs/solid/control/singletondefs.h

   1 /*  This file is part of the KDE project
   2     Copyright (C) 2006-2007 Kevin Ottens <ervin@kde.org>
   3
   4     This library is free software; you can redistribute it and/or
   5     modify it under the terms of the GNU Library General Public
   6     License version 2 as published by the Free Software Foundation.
   7
   8     This library is distributed in the hope that it will be useful,
   9     but WITHOUT ANY WARRANTY; without even the implied warranty of
  10     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11     Library General Public License for more details.
  12
  13     You should have received a copy of the GNU Library General Public License
  14     along with this library; see the file COPYING.LIB.  If not, write to
  15     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  16     Boston, MA 02110-1301, USA.
  17
  18 */
  19
  20 #ifndef SOLID_SINGLETONDEFS_H
  21 #define SOLID_SINGLETONDEFS_H
  22
  23 #include <kglobal.h>
  24
  25 class QObject;
  26
  27 namespace Solid
  28 {
  29 namespace Control
  30 {
  31     /**
  32      * @internal
  33      */
  34     template<typename T>
  35     class SingletonHelper { public: T instance; };
  36
  37 #define SOLID_SINGLETON(Type)                                   \
  38 public:                                                           \
  39     static Type &self();                                          \
  40     static Type &selfForceBackend(QObject *backend);            \
  41 private:                                                          \
  42     friend class Solid::Control::SingletonHelper< Type >;
  43
  44 #define SOLID_SINGLETON_IMPLEMENTATION(Type, Name)              \
  45     K_GLOBAL_STATIC(Solid::Control::SingletonHelper< Type >, global##Name) \
  46                                                                   \
  47     Type &Type::self()                                            \
  48     {                                                             \
  49         Solid::Control::SingletonHelper< Type > *singleton = global##Name; \
  50                                                                   \
  51         return singleton->instance;                               \
  52     }
  53 }
  54 }
  55
  56 #endif