- /*
- Fixed Size Allocator
- Date:
- 2002/03/05
- Note:
- 皋葛府 且寸/秦力俊 靛绰 厚侩(Cost)苞 窜祈拳(Fragmentation)甫 临捞扁 困茄 努贰胶
- */
- #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