Singleton.hpp

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/* This file is part of Berserk Engine project                                    */
/* https://github.com/EgorOrachyov/Berserk                                        */
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/* Copyright (c) 2018 - 2021 Egor Orachyov                                        */
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#ifndef BERSERK_SINGLETON_HPP
#define BERSERK_SINGLETON_HPP
 
#include <core/Config.hpp>
 
BRK_NS_BEGIN
 
template<typename TInstance>
class Singleton {
public:
    static TInstance *InstancePointer() {
        return mInstancePointer;
    }
 
    static TInstance &Instance() {
        return *mInstancePointer;
    }
 
protected:
    static void Provide(TInstance *reference) {
        if (mInstancePointer == nullptr) {
            mInstancePointer = reference;
        }
    }
 
    static void Remove(TInstance *reference) {
        if (mInstancePointer == reference) {
            mInstancePointer = nullptr;
        }
    }
 
private:
    static TInstance *mInstancePointer;
};
 
template<typename TInstance>
TInstance *Singleton<TInstance>::mInstancePointer = nullptr;
 
BRK_NS_END
 
#endif//BERSERK_SINGLETON_HPP