www.pudn.com > evil’s illusion Server Codes.rar > fsa.h


 
 
/* 
	Fixed Size Allocator 
 
	Date: 
		2002/03/05 
 
	Note: 
		메모리 할당/해제에 드는 비용(Cost)과 단편화(Fragmentation)를 줄이기 위한 클래스 
*/ 
#ifndef __ORZ_MEMORY_ALLOCATOR__ 
#define __ORZ_MEMORY_ALLOCATOR__ 
 
 
template< class T > 
class CFixedSizeAllocator 
{ 
public: 
	class CMemBlock 
	{ 
	public: 
		T			tData; 
		CMemBlock	*pNext; 
	}; 
 
protected: 
	CMemBlock *	m_pMemory; 
	CMemBlock * m_pFirstFree; 
	int			m_nCapacity; 
 
public: 
	CFixedSizeAllocator( int nCapacity ); 
	virtual ~CFixedSizeAllocator(); 
 
	T *  Alloc(); 
	void Free( T *pMemory ); 
 
protected: 
	void ConstructFreeList( int nFrom, int nTo ); 
}; 
 
 
template< class T > 
CFixedSizeAllocator< T >::CFixedSizeAllocator( int nCapacity ) 
: m_nCapacity( nCapacity ) 
{ 
	m_pMemory = new CMemBlock[ nCapacity ]; 
	if ( !m_pMemory ) 
		m_nCapacity = 0; 
 
	ConstructFreeList( 0, m_nCapacity ); 
} 
 
 
template< class T > 
CFixedSizeAllocator< T >::~CFixedSizeAllocator() 
{ 
	if ( m_pMemory ) 
		delete[] m_pMemory; 
} 
 
 
template< class T > 
T * CFixedSizeAllocator< T >::Alloc() 
{ 
	if ( !m_pFirstFree ) 
		return NULL; 
	 
	CMemBlock *pBlock	= m_pFirstFree; 
	m_pFirstFree		= pBlock->pNext; 
 
	return (T *) pBlock; 
} 
 
 
template< class T > 
void CFixedSizeAllocator< T >::Free( T *pMemory ) 
{ 
	CMemBlock *pBlock = (CMemBlock *) pMemory; 
 
	pBlock->pNext = m_pFirstFree; 
	m_pFirstFree  = pBlock; 
} 
 
 
template< class T > 
void CFixedSizeAllocator< T >::ConstructFreeList( int nFrom, int nTo ) 
{ 
	CMemBlock *pBaseMemory	= &m_pMemory[nFrom]; 
	m_pFirstFree			= pBaseMemory; 
 
	for ( int i = nFrom + 1; i < nTo; i++ ) 
	{ 
		pBaseMemory->pNext = pBaseMemory + 1; 
		pBaseMemory++; 
	} 
 
	pBaseMemory->pNext = NULL; 
} 
 
 
#endif