mem.h

日本著名的的嵌入式实时操作系统T-Kernel的源码及用户手册。

/*
 *----------------------------------------------------------------------
 *    T-Kernel
 *
 *    Copyright (C) 2004 by Ken Sakamura. All rights reserved.
 *    T-Kernel is distributed under the T-License.
 *----------------------------------------------------------------------
 *
 *    Version:   1.01.00
 *    Released by T-Engine Forum(http://www.t-engine.org) at 2004/6/28.
 *
 *----------------------------------------------------------------------
 */

/*
 *	@(#)mem.h (libtk)
 *
 *	Memory local allocation library 
 */

#include <basic.h>
#include <sys/memalloc.h>
#include <libstr.h>

/*
 * Minimum fragmentation unit 
 *	Since memory is allocated in ROUNDSZ units,
 *	the lower three bits of the address must be 0.
 *	These low three bits are used in the flag in the area queue.
 */
#define	ROUNDSZ		( sizeof(QUEUE) )	/* 8 byte */
#define	ROUND(sz)	( ((sz) + (ROUNDSZ-1)) & ~(ROUNDSZ-1) )

/* Minimum fragment size */
#define	MIN_FRAGMENT	( _mem_minfragment )

/*
 * Flag that uses the lower bits of the area queue prev  
 */
#define	AREA_USE	0x00000001	/* In use */
#define	AREA_TOP	0x00000002	/* Top of page */
#define	AREA_END	0x00000004	/* End of page */
#define	AREA_MASK	0x00000007

#define	setAreaFlag(q, f)     ( (q)->prev = (QUEUE*)((UW)(q)->prev |  (f)) )
#define	clrAreaFlag(q, f)     ( (q)->prev = (QUEUE*)((UW)(q)->prev & ~(f)) )
#define	chkAreaFlag(q, f)     ( ((UW)(q)->prev & (f)) != 0 )

#define	Mask(x)		( (QUEUE*)((UW)(x) & ~AREA_MASK) )
#define	Assign(x, y)	( (x) = (QUEUE*)(((UW)(x) & AREA_MASK) | (UW)(y)) )

/*
 * Area size 
 */
#define	AreaSize(aq)	( (VB*)(aq)->next - (VB*)((aq) + 1) )
#define	FreeSize(fq)	( (VB*)((fq) - 1)->next - (VB*)(fq) )

/*
 * Memory allocation check function
 */
IMPORT BOOL (*_mem_chkalloc)( void *ptr, int mode, MACB *macb );