Many files:

[thirdparty/e2fsprogs.git] / lib / ext2fs / bitops.c

/*
 * bitops.c --- Bitmap frobbing code.  See bitops.h for the inlined
 * 	routines.
 * 
 * Copyright (C) 1993, 1994 Theodore Ts'o.  This file may be
 * redistributed under the terms of the GNU Public License.
 * 
 * Taken from <asm/bitops.h>, Copyright 1992, Linus Torvalds.
 */

#include <stdio.h>
#include <sys/types.h>

#include <linux/ext2_fs.h>

#include "ext2fs.h"

#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 assmebly language, if at all possible.
 * To guarantee atomicity, these routines call cli() and sti() to
 * disable interrupts while they operate.  (You have to provide inline
 * routines to cli() and sti().)
 *
 * Also note, these routines assume that you have 32 bit integers.
 * You will have to change this if you are trying to port Linux to the
 * Alpha architecture or to a Cray.  :-)
 * 
 * C language equivalents written by Theodore Ts'o, 9/26/92
 */

int set_bit(int nr,void * addr)
{
	int	mask, retval;
	int	*ADDR = (int *) addr;

	ADDR += nr >> 5;
	mask = 1 << (nr & 0x1f);
	cli();
	retval = (mask & *ADDR) != 0;
	*ADDR |= mask;
	sti();
	return retval;
}

int clear_bit(int nr, void * addr)
{
	int	mask, retval;
	int	*ADDR = (int *) addr;

	ADDR += nr >> 5;
	mask = 1 << (nr & 0x1f);
	cli();
	retval = (mask & *ADDR) != 0;
	*ADDR &= ~mask;
	sti();
	return retval;
}

int test_bit(int nr, const void * addr)
{
	int		mask;
	const int	*ADDR = (const int *) addr;

	ADDR += nr >> 5;
	mask = 1 << (nr & 0x1f);
	return ((mask & *ADDR) != 0);
}
#endif	/* !_EXT2_HAVE_ASM_BITOPS_ */

void ext2fs_warn_bitmap(errcode_t errcode, unsigned long arg,
			const char *description)
{
	if (description)
		com_err(0, errcode, "#%u for %s", arg, description);
	else
		com_err(0, errcode, "#%u", arg);
}