WiiFlow_Lite/portlibs/sources/libntfs/bitmap.h
2012-01-21 20:57:41 +00:00

97 lines
2.9 KiB
C

/*
* bitmap.h - Exports for bitmap handling. Originated from the Linux-NTFS project.
*
* Copyright (c) 2000-2004 Anton Altaparmakov
* Copyright (c) 2004-2005 Richard Russon
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program/include file is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (in the main directory of the NTFS-3G
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _NTFS_BITMAP_H
#define _NTFS_BITMAP_H
#include "types.h"
#include "attrib.h"
/*
* NOTES:
*
* - Operations are 8-bit only to ensure the functions work both on little
* and big endian machines! So don't make them 32-bit ops!
* - bitmap starts at bit = 0 and ends at bit = bitmap size - 1.
* - _Caller_ has to make sure that the bit to operate on is less than the
* size of the bitmap.
*/
extern void ntfs_bit_set(u8 *bitmap, const u64 bit, const u8 new_value);
extern char ntfs_bit_get(const u8 *bitmap, const u64 bit);
extern char ntfs_bit_get_and_set(u8 *bitmap, const u64 bit, const u8 new_value);
extern int ntfs_bitmap_set_run(ntfs_attr *na, s64 start_bit, s64 count);
extern int ntfs_bitmap_clear_run(ntfs_attr *na, s64 start_bit, s64 count);
/**
* ntfs_bitmap_set_bit - set a bit in a bitmap
* @na: attribute containing the bitmap
* @bit: bit to set
*
* Set the @bit in the bitmap described by the attribute @na.
*
* On success return 0 and on error return -1 with errno set to the error code.
*/
static __inline__ int ntfs_bitmap_set_bit(ntfs_attr *na, s64 bit)
{
return ntfs_bitmap_set_run(na, bit, 1);
}
/**
* ntfs_bitmap_clear_bit - clear a bit in a bitmap
* @na: attribute containing the bitmap
* @bit: bit to clear
*
* Clear @bit in the bitmap described by the attribute @na.
*
* On success return 0 and on error return -1 with errno set to the error code.
*/
static __inline__ int ntfs_bitmap_clear_bit(ntfs_attr *na, s64 bit)
{
return ntfs_bitmap_clear_run(na, bit, 1);
}
/*
* rol32 - rotate a 32-bit value left
*
* @word: value to rotate
* @shift: bits to roll
*/
static __inline__ u32 ntfs_rol32(u32 word, unsigned int shift)
{
return (word << shift) | (word >> (32 - shift));
}
/*
* ror32 - rotate a 32-bit value right
*
* @word: value to rotate
* @shift: bits to roll
*/
static __inline__ u32 ntfs_ror32(u32 word, unsigned int shift)
{
return (word >> shift) | (word << (32 - shift));
}
#endif /* defined _NTFS_BITMAP_H */