Fast, Low Latency and Non-synchronizing Trace Class

// singleton.h
//
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//
// 19.07.2001 : Tim Hagemann
//  - created
//
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

#ifndef singletonH
#define singletonH

#include <memory>

template <class T> class CreateImplementation
{
public:
        static T *CreateNew(void)
        {
            return new T;
        }
};

template <class T,typename CreatePolicy = CreateImplementation<T> > class Singleton
{
public:
    //--- d'tor is public. Will shutdown the implementation implicitly 

    ~Singleton()
    {
        Shutdown();
    }

    // -- acessors
	
	// --- static Get will create the singleton using an auto-ptr

    static Singleton &Get()
    {
        if (m_InstancePtr.get() == NULL) m_InstancePtr = std::auto_ptr<Singleton>(new Singleton);
        return *m_InstancePtr;
    }

	// --- static Get will create the singleton using an auto-ptr

    static bool IsAvailable(void)
    {      
        if (!m_InstancePtr.get()) return false;

        return (m_InstancePtr->m_Implementation != NULL);

    }

	// --- this will create the implementation implicitly

    T *operator -> ()
    {
		Startup();
        return m_Implementation;
    }

	// --- this will create the implementation explicitly

    void Startup(void)
    {
        if (m_Implementation == NULL)
		{
			m_Implementation = CreatePolicy::CreateNew();
		}
    }

	// --- this will shutdown the implementation 

    void Shutdown(void)
    {
        if (m_Implementation)
        {
			delete m_Implementation;
			m_Implementation = NULL;
		}
    }
    void Restart(void)
    {
        Shutdown();
        Startup();
    }

protected:
    //--- c'tor,copy-c'tor and assignment are forbidden 

    Singleton()
    {
        m_Implementation = NULL;
    }

    Singleton(const Singleton &copy)
    {
        ESG_ASSERT(false);
    }

    void operator = (const Singleton &copy)
    {
        ESG_ASSERT(false);
    }

	// --- auto_ptr of singleton class. Will remove the singleton on app shutdown

    static std::auto_ptr<Singleton>  m_InstancePtr;
    T *m_Implementation;
};

#endif