1 /* Copyright (C) 2019 Wildfire Games.
2 * This file is part of 0 A.D.
4 * 0 A.D. is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 2 of the License, or
7 * (at your option) any later version.
9 * 0 A.D. is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with 0 A.D. If not, see <http://www.gnu.org/licenses/>.
18 #ifndef INCLUDED_SINGLETON
19 #define INCLUDED_SINGLETON
21 #include "lib/debug.h"
24 * Template base class for singletons.
27 * class MyClass : public Singleton<MyClass> {};
28 * MyClass::GetSingleton().MyMethod();
30 * Modified from http://gamedev.net/reference/articles/article1954.asp
35 NONCOPYABLE(Singleton
);
39 ENSURE(!ms_singleton
);
40 ms_singleton
= static_cast<T
*>(this);
46 ms_singleton
= nullptr;
49 static T
& GetSingleton()
55 static T
* GetSingletonPtr()
61 static bool IsInitialised()
63 return ms_singleton
!= nullptr;
67 static T
* ms_singleton
;
71 T
* Singleton
<T
>::ms_singleton
= nullptr;
73 #endif // INCLUDED_SINGLETON