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/*
* Copyright (c) 2003 Marcel Moolenaar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_GNU_EXT2FS_EXT2_BITOPS_H_
#define _SYS_GNU_EXT2FS_EXT2_BITOPS_H_
#define find_first_zero_bit(data, sz) find_next_zero_bit(data, sz, 0)
static __inline int
clear_bit(int no, void *data)
{
uint32_t *p;
uint32_t mask, new, old;
p = (uint32_t*)data + (no >> 5);
mask = (1U << (no & 31));
do {
old = *p;
new = old & ~mask;
} while (!atomic_cmpset_32(p, old, new));
return (old & mask);
}
static __inline int
set_bit(int no, void *data)
{
uint32_t *p;
uint32_t mask, new, old;
p = (uint32_t*)data + (no >> 5);
mask = (1U << (no & 31));
do {
old = *p;
new = old | mask;
} while (!atomic_cmpset_32(p, old, new));
return (old & mask);
}
static __inline int
test_bit(int no, void *data)
{
uint32_t *p;
uint32_t mask;
p = (uint32_t*)data + (no >> 5);
mask = (1U << (no & 31));
return (*p & mask);
}
static __inline size_t
find_next_zero_bit(void *data, size_t sz, size_t ofs)
{
uint32_t *p;
uint32_t mask;
int bit;
p = (uint32_t*)data + (ofs >> 5);
if (ofs & 31) {
mask = ~0U << (ofs & 31);
bit = *p | ~mask;
if (bit != ~0U)
return (ffs(~bit) + ofs - 1);
p++;
ofs = (ofs + 31U) & ~31U;
}
while(*p == ~0U && ofs < sz) {
p++;
ofs += 32;
}
if (ofs == sz)
return (ofs);
bit = *p;
return (ffs(~bit) + ofs - 1);
}
static __inline void *
memscan(void *data, int c, size_t sz)
{
uint8_t *p;
p = data;
while (sz && *p != c) {
p++;
sz--;
}
return (p);
}
#endif /* _SYS_GNU_EXT2FS_EXT2_BITOPS_H_ */
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