modules/gui/qt4/util/singleton.hpp

   1 /*****************************************************************************
   2  * singleton.hpp: Generic Singleton pattern implementation
   3  ****************************************************************************
   4  * Copyright (C) 2009 VideoLAN
   5  *
   6  * Authors: Hugo Beauzee-Luyssen <beauze.h # gmail - com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software Foundation, Inc.,
  20  * 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #ifndef _SINGLETON_HPP_
  24 #define _SINGLETON_HPP_
  25
  26 #include <stdlib.h>
  27 #include "qt4.hpp"
  28
  29 template <typename T>
  30 class       Singleton
  31 {
  32 public:
  33     static T*      getInstance( intf_thread_t *p_intf = NULL )
  34     {
  35         if ( m_instance == NULL )
  36             m_instance = new T( p_intf );
  37         return m_instance;
  38     }
  39
  40     static void    killInstance()
  41     {
  42         if ( m_instance != NULL )
  43         {
  44             delete m_instance;
  45             m_instance = NULL;
  46         }
  47     }
  48 protected:
  49     Singleton(){}
  50     virtual ~Singleton(){}
  51     /* Not implemented since these methods should *NEVER* been called.
  52     If they do, it probably won't compile :) */
  53     Singleton(const Singleton<T>&);
  54     Singleton<T>&   operator=(const Singleton<T>&);
  55
  56 private:
  57     static T*      m_instance;
  58 };
  59
  60 template <typename T>
  61 T*  Singleton<T>::m_instance = NULL;
  62
  63 #endif // _SINGLETON_HPP_