xfs_bit.h 2.0 KB

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  1. /*
  2. * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
  3. * All Rights Reserved.
  4. *
  5. * This program is free software; you can redistribute it and/or
  6. * modify it under the terms of the GNU General Public License as
  7. * published by the Free Software Foundation.
  8. *
  9. * This program is distributed in the hope that it would be useful,
  10. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12. * GNU General Public License for more details.
  13. *
  14. * You should have received a copy of the GNU General Public License
  15. * along with this program; if not, write the Free Software Foundation,
  16. * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  17. */
  18. #ifndef __XFS_BIT_H__
  19. #define __XFS_BIT_H__
  20. /*
  21. * XFS bit manipulation routines.
  22. */
  23. /*
  24. * masks with n high/low bits set, 32-bit values & 64-bit values
  25. */
  26. #define XFS_MASK32HI(n) xfs_mask32hi(n)
  27. static inline __uint32_t xfs_mask32hi(int n)
  28. {
  29. return (__uint32_t)-1 << (32 - (n));
  30. }
  31. #define XFS_MASK64HI(n) xfs_mask64hi(n)
  32. static inline __uint64_t xfs_mask64hi(int n)
  33. {
  34. return (__uint64_t)-1 << (64 - (n));
  35. }
  36. #define XFS_MASK32LO(n) xfs_mask32lo(n)
  37. static inline __uint32_t xfs_mask32lo(int n)
  38. {
  39. return ((__uint32_t)1 << (n)) - 1;
  40. }
  41. #define XFS_MASK64LO(n) xfs_mask64lo(n)
  42. static inline __uint64_t xfs_mask64lo(int n)
  43. {
  44. return ((__uint64_t)1 << (n)) - 1;
  45. }
  46. /* Get high bit set out of 32-bit argument, -1 if none set */
  47. extern int xfs_highbit32(__uint32_t v);
  48. /* Get low bit set out of 64-bit argument, -1 if none set */
  49. extern int xfs_lowbit64(__uint64_t v);
  50. /* Get high bit set out of 64-bit argument, -1 if none set */
  51. extern int xfs_highbit64(__uint64_t);
  52. /* Count set bits in map starting with start_bit */
  53. extern int xfs_count_bits(uint *map, uint size, uint start_bit);
  54. /* Count continuous one bits in map starting with start_bit */
  55. extern int xfs_contig_bits(uint *map, uint size, uint start_bit);
  56. /* Find next set bit in map */
  57. extern int xfs_next_bit(uint *map, uint size, uint start_bit);
  58. #endif /* __XFS_BIT_H__ */