xref: /illumos-gate/usr/src/cmd/sendmail/db/db/db_log2.c (revision 7c478bd9)
1*7c478bd9Sstevel@tonic-gate /*-
2*7c478bd9Sstevel@tonic-gate  * See the file LICENSE for redistribution information.
3*7c478bd9Sstevel@tonic-gate  *
4*7c478bd9Sstevel@tonic-gate  * Copyright (c) 1996, 1997, 1998
5*7c478bd9Sstevel@tonic-gate  *	Sleepycat Software.  All rights reserved.
6*7c478bd9Sstevel@tonic-gate  */
7*7c478bd9Sstevel@tonic-gate /*
8*7c478bd9Sstevel@tonic-gate  * Copyright (c) 1995, 1996
9*7c478bd9Sstevel@tonic-gate  *	The Regents of the University of California.  All rights reserved.
10*7c478bd9Sstevel@tonic-gate  *
11*7c478bd9Sstevel@tonic-gate  * This code is derived from software contributed to Berkeley by
12*7c478bd9Sstevel@tonic-gate  * Margo Seltzer.
13*7c478bd9Sstevel@tonic-gate  *
14*7c478bd9Sstevel@tonic-gate  * Redistribution and use in source and binary forms, with or without
15*7c478bd9Sstevel@tonic-gate  * modification, are permitted provided that the following conditions
16*7c478bd9Sstevel@tonic-gate  * are met:
17*7c478bd9Sstevel@tonic-gate  * 1. Redistributions of source code must retain the above copyright
18*7c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer.
19*7c478bd9Sstevel@tonic-gate  * 2. Redistributions in binary form must reproduce the above copyright
20*7c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer in the
21*7c478bd9Sstevel@tonic-gate  *    documentation and/or other materials provided with the distribution.
22*7c478bd9Sstevel@tonic-gate  * 3. All advertising materials mentioning features or use of this software
23*7c478bd9Sstevel@tonic-gate  *    must display the following acknowledgement:
24*7c478bd9Sstevel@tonic-gate  *	This product includes software developed by the University of
25*7c478bd9Sstevel@tonic-gate  *	California, Berkeley and its contributors.
26*7c478bd9Sstevel@tonic-gate  * 4. Neither the name of the University nor the names of its contributors
27*7c478bd9Sstevel@tonic-gate  *    may be used to endorse or promote products derived from this software
28*7c478bd9Sstevel@tonic-gate  *    without specific prior written permission.
29*7c478bd9Sstevel@tonic-gate  *
30*7c478bd9Sstevel@tonic-gate  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31*7c478bd9Sstevel@tonic-gate  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32*7c478bd9Sstevel@tonic-gate  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33*7c478bd9Sstevel@tonic-gate  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34*7c478bd9Sstevel@tonic-gate  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35*7c478bd9Sstevel@tonic-gate  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36*7c478bd9Sstevel@tonic-gate  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37*7c478bd9Sstevel@tonic-gate  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38*7c478bd9Sstevel@tonic-gate  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39*7c478bd9Sstevel@tonic-gate  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40*7c478bd9Sstevel@tonic-gate  * SUCH DAMAGE.
41*7c478bd9Sstevel@tonic-gate  */
42*7c478bd9Sstevel@tonic-gate 
43*7c478bd9Sstevel@tonic-gate #include "config.h"
44*7c478bd9Sstevel@tonic-gate 
45*7c478bd9Sstevel@tonic-gate #ifndef lint
46*7c478bd9Sstevel@tonic-gate static const char sccsid[] = "@(#)db_log2.c	10.5 (Sleepycat) 4/26/98";
47*7c478bd9Sstevel@tonic-gate #endif /* not lint */
48*7c478bd9Sstevel@tonic-gate 
49*7c478bd9Sstevel@tonic-gate #ifndef NO_SYSTEM_INCLUDES
50*7c478bd9Sstevel@tonic-gate #include <sys/types.h>
51*7c478bd9Sstevel@tonic-gate #endif
52*7c478bd9Sstevel@tonic-gate 
53*7c478bd9Sstevel@tonic-gate #include "db_int.h"
54*7c478bd9Sstevel@tonic-gate #include "common_ext.h"
55*7c478bd9Sstevel@tonic-gate 
56*7c478bd9Sstevel@tonic-gate /*
57*7c478bd9Sstevel@tonic-gate  * PUBLIC: u_int32_t __db_log2 __P((u_int32_t));
58*7c478bd9Sstevel@tonic-gate  */
59*7c478bd9Sstevel@tonic-gate u_int32_t
__db_log2(num)60*7c478bd9Sstevel@tonic-gate __db_log2(num)
61*7c478bd9Sstevel@tonic-gate 	u_int32_t num;
62*7c478bd9Sstevel@tonic-gate {
63*7c478bd9Sstevel@tonic-gate 	u_int32_t i, limit;
64*7c478bd9Sstevel@tonic-gate 
65*7c478bd9Sstevel@tonic-gate 	limit = 1;
66*7c478bd9Sstevel@tonic-gate 	for (i = 0; limit < num; limit = limit << 1, i++)
67*7c478bd9Sstevel@tonic-gate 		;
68*7c478bd9Sstevel@tonic-gate 	return (i);
69*7c478bd9Sstevel@tonic-gate }
70