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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 #pragma ident "%Z%%M% %I% %E% SMI" /* from ATT S5R3 */
23
24 /* The following is extracted from... */
25
26 /* Copyright (c) 1984 AT&T */
27 /* All Rights Reserved */
28
29
30 /*
31 * modf(value, iptr) returns the signed fractional part of value
32 * and stores the integer part indirectly through iptr.
33 *
34 */
35
36 #define MAXPOWTWO 4.503599627370496000E+15
37 /* doubles >= MAXPOWTWO are already integers */
38 double
modf(value,iptr)39 modf(value, iptr)
40 double value;
41 register double *iptr;
42 {
43 register double absvalue;
44
45 if ((absvalue = (value >= 0.0) ? value : -value) >= MAXPOWTWO)
46 *iptr = value; /* it must be an integer */
47 else {
48 *iptr = absvalue + MAXPOWTWO; /* shift fraction off right */
49 *iptr -= MAXPOWTWO; /* shift back without fraction */
50 while (*iptr > absvalue) /* above arithmetic might round */
51 *iptr -= 1.0; /* test again just to be sure */
52 if (value < 0.0)
53 *iptr = -*iptr;
54 }
55 return (value - *iptr); /* signed fractional part */
56 }
57