1 /* 2 * bitmap.h - Exports for bitmap handling. Originated from the Linux-NTFS project. 3 * 4 * Copyright (c) 2000-2004 Anton Altaparmakov 5 * Copyright (c) 2004-2005 Richard Russon 6 * 7 * This program/include file is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License as published 9 * by the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program/include file is distributed in the hope that it will be 13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program (in the main directory of the NTFS-3G 19 * distribution in the file COPYING); if not, write to the Free Software 20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23 #ifndef _NTFS_BITMAP_H 24 #define _NTFS_BITMAP_H 25 26 #include "types.h" 27 #include "attrib.h" 28 29 /* 30 * NOTES: 31 * 32 * - Operations are 8-bit only to ensure the functions work both on little 33 * and big endian machines! So don't make them 32-bit ops! 34 * - bitmap starts at bit = 0 and ends at bit = bitmap size - 1. 35 * - _Caller_ has to make sure that the bit to operate on is less than the 36 * size of the bitmap. 37 */ 38 39 extern void ntfs_bit_set(u8 *bitmap, const u64 bit, const u8 new_value); 40 extern char ntfs_bit_get(const u8 *bitmap, const u64 bit); 41 extern char ntfs_bit_get_and_set(u8 *bitmap, const u64 bit, const u8 new_value); 42 extern int ntfs_bitmap_set_run(ntfs_attr *na, s64 start_bit, s64 count); 43 extern int ntfs_bitmap_clear_run(ntfs_attr *na, s64 start_bit, s64 count); 44 45 /** 46 * ntfs_bitmap_set_bit - set a bit in a bitmap 47 * @na: attribute containing the bitmap 48 * @bit: bit to set 49 * 50 * Set the @bit in the bitmap described by the attribute @na. 51 * 52 * On success return 0 and on error return -1 with errno set to the error code. 53 */ 54 static __inline__ int ntfs_bitmap_set_bit(ntfs_attr *na, s64 bit) 55 { 56 return ntfs_bitmap_set_run(na, bit, 1); 57 } 58 59 /** 60 * ntfs_bitmap_clear_bit - clear a bit in a bitmap 61 * @na: attribute containing the bitmap 62 * @bit: bit to clear 63 * 64 * Clear @bit in the bitmap described by the attribute @na. 65 * 66 * On success return 0 and on error return -1 with errno set to the error code. 67 */ 68 static __inline__ int ntfs_bitmap_clear_bit(ntfs_attr *na, s64 bit) 69 { 70 return ntfs_bitmap_clear_run(na, bit, 1); 71 } 72 73 /* 74 * rol32 - rotate a 32-bit value left 75 * 76 * @word: value to rotate 77 * @shift: bits to roll 78 */ 79 static __inline__ u32 ntfs_rol32(u32 word, unsigned int shift) 80 { 81 return (word << shift) | (word >> (32 - shift)); 82 } 83 84 /* 85 * ror32 - rotate a 32-bit value right 86 * 87 * @word: value to rotate 88 * @shift: bits to roll 89 */ 90 static __inline__ u32 ntfs_ror32(u32 word, unsigned int shift) 91 { 92 return (word >> shift) | (word << (32 - shift)); 93 } 94 95 #endif /* defined _NTFS_BITMAP_H */ 96 97