File: [Development] / xfs-linux / xfs_bit.h (download)
Revision 1.3, Thu May 11 01:22:56 1995 UTC (22 years, 5 months ago) by ajs
Branch: MAIN
Changes since 1.2: +2 -2
lines
272139 - Change xFS to XFS
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#ifndef _FS_XFS_BIT_H
#define _FS_XFS_BIT_H
#ident "$Revision: 1.2 $"
/*
* XFS bit manipulation routines.
*/
/*
* masks with n high/low bits set, 32-bit values & 64-bit values
*/
#define XFS_MASK32HI(n) ((__uint32_t)-1 << (32 - (n)))
#define XFS_MASK64HI(n) ((__uint64_t)-1 << (64 - (n)))
#define XFS_MASK32LO(n) (((__uint32_t)1 << (n)) - 1)
#define XFS_MASK64LO(n) (((__uint64_t)1 << (n)) - 1)
/*
* Index of low bit number in byte, -1 for none set, 0..7 otherwise.
*/
extern const char xfs_lowbit[256];
/*
* Index of high bit number in byte, -1 for none set, 0..7 otherwise.
*/
extern const char xfs_highbit[256];
/*
* Count of bits set in byte, 0..8.
*/
extern const char xfs_countbit[256];
/*
* xfs_lowbit32: get low bit set out of 32-bit argument, -1 if none set.
*/
extern int xfs_lowbit32(__uint32_t v);
/*
* xfs_highbit32: get high bit set out of 32-bit argument, -1 if none set.
*/
extern int xfs_highbit32(__uint32_t v);
/*
* xfs_lowbit64: get low bit set out of 64-bit argument, -1 if none set.
*/
extern int xfs_lowbit64(__uint64_t v);
/*
* xfs_highbit64: get high bit set out of 64-bit argument, -1 if none set.
*/
extern int xfs_highbit64(__uint64_t);
#endif /* _FS_XFS_BIT_H */