libpam: Play some 4D chess for static pam modules support.
[dragonfly.git] / sys / libkern / ffsl.c
blob97cec6aca6080325576a275301fcf839d30df9a4
1 /*-
2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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27 * SUCH DAMAGE.
29 * $FreeBSD: head/sys/libkern/ffsl.c 128019 2004-04-07 20:46:16Z imp $
32 #include <sys/libkern.h>
35 * Find First Set bit
37 int
38 ffsl(long mask)
40 int bit;
42 if (mask == 0)
43 return (0);
44 for (bit = 1; !(mask & 1); bit++)
45 mask = (unsigned long)mask >> 1;
46 return (bit);