1/*-
2 * See the file LICENSE for redistribution information.
3 *
4 * Copyright (c) 1996,2008 Oracle.  All rights reserved.
5 */
6/*
7 * Copyright (c) 1995, 1996
8 *	The Regents of the University of California.  All rights reserved.
9 *
10 * This code is derived from software contributed to Berkeley by
11 * Margo Seltzer.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 *    notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 *    notice, this list of conditions and the following disclaimer in the
20 *    documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * $Id: db_log2.c,v 12.7 2008/01/08 20:58:08 bostic Exp $
38 */
39
40#include "db_config.h"
41
42#include "db_int.h"
43
44/*
45 * PUBLIC: u_int32_t __db_log2 __P((u_int32_t));
46 */
47u_int32_t
48__db_log2(num)
49	u_int32_t num;
50{
51	u_int32_t i, limit;
52
53	limit = 1;
54	for (i = 0; limit < num; limit = limit << 1)
55		++i;
56	return (i);
57}
58