65 lines
1.6 KiB
C++
Executable File
65 lines
1.6 KiB
C++
Executable File
//////////////////////////////////////////////////////////////////////////////
|
|
// AUTHOR: Michael Reiland
|
|
// FILENAME: Singleton.h
|
|
// PURPOSE: Provides a base template class for Singletons
|
|
//
|
|
// USEAGE: class myClass : Singleton<myClass>{};
|
|
//
|
|
// INFO: This implementation was copied from:
|
|
//
|
|
// Enginuity, Part II
|
|
// Memory Management, Error Logging, and Utility Classes;
|
|
// or, How To Forget To Explode Your Underwear
|
|
// by Richard "superpig" Fine
|
|
//
|
|
// hosted at Gamedev.net at
|
|
// http://gamedev.net/reference/articles/article1954.asp
|
|
//
|
|
// MODIFIED: 07.09.2003 mreiland
|
|
#ifndef _TEMPLATE_SINGLETON
|
|
#define _TEMPLATE_SINGLETON
|
|
|
|
#include <assert.h>
|
|
#include "lib.h"
|
|
|
|
|
|
template<typename T>
|
|
class Singleton
|
|
{
|
|
static T* ms_singleton;
|
|
|
|
public:
|
|
Singleton()
|
|
{
|
|
assert( !ms_singleton );
|
|
|
|
//use a cunning trick to get the singleton pointing to the start of
|
|
//the whole, rather than the start of the Singleton part of the object
|
|
uintptr_t offset = (uintptr_t)(T*)1 - (uintptr_t)(Singleton<T>*)(T*)1;
|
|
ms_singleton = (T*)((uintptr_t)this + offset);
|
|
}
|
|
|
|
~Singleton()
|
|
{
|
|
assert( ms_singleton );
|
|
ms_singleton=0;
|
|
}
|
|
|
|
static T& GetSingleton()
|
|
{
|
|
assert( ms_singleton );
|
|
return *ms_singleton;
|
|
}
|
|
|
|
static T* GetSingletonPtr()
|
|
{
|
|
assert( ms_singleton );
|
|
return ms_singleton;
|
|
}
|
|
};
|
|
|
|
template <typename T>
|
|
T* Singleton<T>::ms_singleton = 0;
|
|
|
|
#endif
|