bitops.c revision 50e1e10fa0ac12a3e2a9d20a75ee9041873cda96 
1/*
2 * bitops.c --- Bitmap frobbing code.  See bitops.h for the inlined
3 * 	routines.
4 *
5 * Copyright (C) 1993, 1994 Theodore Ts'o.  This file may be
6 * redistributed under the terms of the GNU Public License.
7 *
8 * Taken from <asm/bitops.h>, Copyright 1992, Linus Torvalds.
9 */
10
11#include <stdio.h>
12#include <sys/types.h>
13
14#include <linux/ext2_fs.h>
15
16#include "ext2fs.h"
17
18#ifndef _EXT2_HAVE_ASM_BITOPS_
19
20/*
21 * For the benefit of those who are trying to port Linux to another
22 * architecture, here are some C-language equivalents.  You should
23 * recode these in the native assmebly language, if at all possible.
24 *
25 * C language equivalents written by Theodore Ts'o, 9/26/92.
26 * Modified by Pete A. Zaitcev 7/14/95 to be portable to big endian
27 * systems, as well as non-32 bit systems.
28 */
29
30int set_bit(int nr,void * addr)
31{
32	int		mask, retval;
33	unsigned char	*ADDR = (unsigned char *) addr;
34
35	ADDR += nr >> 3;
36	mask = 1 << (nr & 0x07);
37	retval = (mask & *ADDR) != 0;
38	*ADDR |= mask;
39	return retval;
40}
41
42int clear_bit(int nr, void * addr)
43{
44	int		mask, retval;
45	unsigned char	*ADDR = (unsigned char *) addr;
46
47	ADDR += nr >> 3;
48	mask = 1 << (nr & 0x07);
49	retval = (mask & *ADDR) != 0;
50	*ADDR &= ~mask;
51	return retval;
52}
53
54int test_bit(int nr, const void * addr)
55{
56	int			mask;
57	const unsigned char	*ADDR = (const unsigned char *) addr;
58
59	ADDR += nr >> 3;
60	mask = 1 << (nr & 0x07);
61	return ((mask & *ADDR) != 0);
62}
63
64#endif	/* !_EXT2_HAVE_ASM_BITOPS_ */
65
66void ext2fs_warn_bitmap(errcode_t errcode, unsigned long arg,
67			const char *description)
68{
69	if (description)
70		com_err(0, errcode, "#%u for %s", arg, description);
71	else
72		com_err(0, errcode, "#%u", arg);
73}
74
75