xref: /illumos-gate/usr/src/lib/libc/port/gen/llog10.c (revision 0250c53ad267726f2438e3c6556199a0bbf588a2)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 #include	"lint.h"
31 #include	<sys/types.h>
32 #include	<sys/dl.h>
33 
34 dl_t
35 llog10(dl_t val)
36 {
37 	dl_t	result;
38 
39 	result = lzero;
40 	val    = ldivide(val, lten);
41 
42 	while (val.dl_hop != 0 || val.dl_lop != 0) {
43 		val = ldivide(val, lten);
44 		result = ladd(result, lone);
45 	}
46 
47 	return (result);
48 }
49