linux-sg2042/fs/xfs/xfs_bit.h

86 lines
2.9 KiB
C

/*
* Copyright (c) 2000, 2002 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
*/
#ifndef __XFS_BIT_H__
#define __XFS_BIT_H__
/*
* XFS bit manipulation routines.
*/
/*
* masks with n high/low bits set, 32-bit values & 64-bit values
*/
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK32HI)
__uint32_t xfs_mask32hi(int n);
#define XFS_MASK32HI(n) xfs_mask32hi(n)
#else
#define XFS_MASK32HI(n) ((__uint32_t)-1 << (32 - (n)))
#endif
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK64HI)
__uint64_t xfs_mask64hi(int n);
#define XFS_MASK64HI(n) xfs_mask64hi(n)
#else
#define XFS_MASK64HI(n) ((__uint64_t)-1 << (64 - (n)))
#endif
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK32LO)
__uint32_t xfs_mask32lo(int n);
#define XFS_MASK32LO(n) xfs_mask32lo(n)
#else
#define XFS_MASK32LO(n) (((__uint32_t)1 << (n)) - 1)
#endif
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MASK64LO)
__uint64_t xfs_mask64lo(int n);
#define XFS_MASK64LO(n) xfs_mask64lo(n)
#else
#define XFS_MASK64LO(n) (((__uint64_t)1 << (n)) - 1)
#endif
/* Get high bit set out of 32-bit argument, -1 if none set */
extern int xfs_highbit32(__uint32_t v);
/* Get low bit set out of 64-bit argument, -1 if none set */
extern int xfs_lowbit64(__uint64_t v);
/* Get high bit set out of 64-bit argument, -1 if none set */
extern int xfs_highbit64(__uint64_t);
/* Count set bits in map starting with start_bit */
extern int xfs_count_bits(uint *map, uint size, uint start_bit);
/* Count continuous one bits in map starting with start_bit */
extern int xfs_contig_bits(uint *map, uint size, uint start_bit);
/* Find next set bit in map */
extern int xfs_next_bit(uint *map, uint size, uint start_bit);
#endif /* __XFS_BIT_H__ */