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      1 /*
      2  * bitops.c --- Bitmap frobbing code.  See bitops.h for the inlined
      3  * 	routines.
      4  *
      5  * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
      6  *
      7  * %Begin-Header%
      8  * This file may be redistributed under the terms of the GNU Public
      9  * License.
     10  * %End-Header%
     11  */
     12 
     13 #include <stdio.h>
     14 #if HAVE_SYS_TYPES_H
     15 #include <sys/types.h>
     16 #endif
     17 
     18 #include "ext2_fs.h"
     19 #include "ext2fs.h"
     20 
     21 #ifndef _EXT2_HAVE_ASM_BITOPS_
     22 
     23 /*
     24  * For the benefit of those who are trying to port Linux to another
     25  * architecture, here are some C-language equivalents.  You should
     26  * recode these in the native assmebly language, if at all possible.
     27  *
     28  * C language equivalents written by Theodore Ts'o, 9/26/92.
     29  * Modified by Pete A. Zaitcev 7/14/95 to be portable to big endian
     30  * systems, as well as non-32 bit systems.
     31  */
     32 
     33 int ext2fs_set_bit(unsigned int nr,void * addr)
     34 {
     35 	int		mask, retval;
     36 	unsigned char	*ADDR = (unsigned char *) addr;
     37 
     38 	ADDR += nr >> 3;
     39 	mask = 1 << (nr & 0x07);
     40 	retval = mask & *ADDR;
     41 	*ADDR |= mask;
     42 	return retval;
     43 }
     44 
     45 int ext2fs_clear_bit(unsigned int nr, void * addr)
     46 {
     47 	int		mask, retval;
     48 	unsigned char	*ADDR = (unsigned char *) addr;
     49 
     50 	ADDR += nr >> 3;
     51 	mask = 1 << (nr & 0x07);
     52 	retval = mask & *ADDR;
     53 	*ADDR &= ~mask;
     54 	return retval;
     55 }
     56 
     57 int ext2fs_test_bit(unsigned int nr, const void * addr)
     58 {
     59 	int			mask;
     60 	const unsigned char	*ADDR = (const unsigned char *) addr;
     61 
     62 	ADDR += nr >> 3;
     63 	mask = 1 << (nr & 0x07);
     64 	return (mask & *ADDR);
     65 }
     66 
     67 #endif	/* !_EXT2_HAVE_ASM_BITOPS_ */
     68 
     69 void ext2fs_warn_bitmap(errcode_t errcode, unsigned long arg,
     70 			const char *description)
     71 {
     72 #ifndef OMIT_COM_ERR
     73 	if (description)
     74 		com_err(0, errcode, "#%lu for %s", arg, description);
     75 	else
     76 		com_err(0, errcode, "#%lu", arg);
     77 #endif
     78 }
     79