OpenSolaris_b135/lib/libntfs/common/libntfs/compat.c

/**
 * compat.c - Tweaks for Windows compatibility
 *
 * Copyright (c) 2002 Richard Russon
 * Copyright (c) 2002-2004 Anton Altaparmakov
 *
 * This program/include file is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program/include file is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program (in the main directory of the Linux-NTFS
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifdef WINDOWS

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "compat.h"

/* TODO: Add check for FFS in the configure script... (AIA) */

#ifndef HAVE_FFS
/**
 * ffs - Find the first set bit in an int
 * @x:
 *
 * Description...
 *
 * Returns:
 */
int ffs(int x)
{
	int r = 1;

	if (!x)
		return 0;
	if (!(x & 0xffff)) {
		x >>= 16;
		r += 16;
	}
	if (!(x & 0xff)) {
		x >>= 8;
		r += 8;
	}
	if (!(x & 0xf)) {
		x >>= 4;
		r += 4;
	}
	if (!(x & 3)) {
		x >>= 2;
		r += 2;
	}
	if (!(x & 1)) {
		x >>= 1;
		r += 1;
	}
	return r;
}
#endif /* HAVE_FFS */

#endif /* WINDOWS */