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/*
* bitops.c - bitmap operations
*
* This code has been extracted from e2fsprogs/lib/ext2fs/bitops.c
*/
#ifndef _EXT2_HAVE_ASM_BITOPS_
/*
* For the benefit of those who are trying to port Linux to another
* architecture, here are some C-language equivalents. You should
* recode these in the native assembly language, if at all possible.
*
* C language equivalents written by Theodore Ts'o, 9/26/92.
* Modified by Pete A. Zaitcev 7/14/95 to be portable to big endian
* systems, as well as non-32 bit systems.
*/
int ext2fs_set_bit(int nr, void *addr)
{
int mask, retval;
unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
retval = mask & *ADDR;
*ADDR |= mask;
return retval;
}
int ext2fs_clear_bit(int nr, void *addr)
{
int mask, retval;
unsigned char *ADDR = (unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
retval = mask & *ADDR;
*ADDR &= ~mask;
return retval;
}
int ext2fs_test_bit(int nr, const void *addr)
{
int mask;
const unsigned char *ADDR = (const unsigned char *) addr;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
return mask & *ADDR;
}
#endif /* !_EXT2_HAVE_ASM_BITOPS_ */
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