//******************************************************************************
//
//	File:		BlockCache.h
//
//	Description:	A simple caching mecahnism for fixed size blocks
//
//	Copyright 1995-97, Be Incorporated
//
//******************************************************************************


#ifndef _BLOCK_CACHE_H
#define _BLOCK_CACHE_H

#include <stddef.h>
#include <Locker.h>

/*
 temporary comment:

 The BBlockCache object can be used to transparently cache a blocks of
 memory. In certain situations this can be a substantial performance
 boast. This code is limited to objects that are either managed by
 malloc/free or the C++ new/delete operator. In addition, the blocks
 must be of fixed size.

 B_OBJECT_CACHE:
	 The block of memory being cached is an object that is allocated
	 by the global 'new' operator and disposed of by the global
	 'delete' operator. 

 B_MALLOC_CACHE:
	 The block of memory being cached is allocated and deallocated
	 by the standard malloc/free methods.

*/

enum {
	B_OBJECT_CACHE = 0,
	B_MALLOC_CACHE = 1
};

class BMessage;

// ------------------------------------------------------------------- //

class BBlockCache {
public:
					BBlockCache(size_t cache_size,
								size_t block_size,
								uint32 type);
virtual				~BBlockCache();

		void		*Get(size_t block_size);
		void		Save(void *pointer, size_t block_size);

private:

virtual	void		_ReservedBlockCache1();
virtual	void		_ReservedBlockCache2();

					BBlockCache(const BBlockCache &);
		BBlockCache	&operator=(const BBlockCache &);

		int			fCacheSize;
		void		**fCache;
		int			fMark;
		BLocker		fLock;
		int			fBlkSize;
		void		*(*fAlloc)(size_t size);
		void		(*fFree)(void *);
		uint32		_reserved[2];
};

#endif