xref: /openbsd-src/lib/libc/gen/fpclassify.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: fpclassify.c,v 1.4 2008/12/10 01:15:02 martynas Exp $	*/
2 /*
3  * Copyright (c) 2008 Martynas Venckus <martynas@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/cdefs.h>
20 #include <machine/ieee.h>
21 #include <float.h>
22 #include <math.h>
23 
24 int
25 __fpclassify(double d)
26 {
27 	struct ieee_double *p = (struct ieee_double *)&d;
28 
29 	if (p->dbl_exp == 0) {
30 		if (p->dbl_frach == 0 && p->dbl_fracl == 0)
31 			return FP_ZERO;
32 		else
33 			return FP_SUBNORMAL;
34 	}
35 
36 	if (p->dbl_exp == DBL_EXP_INFNAN) {
37 		if (p->dbl_frach == 0 && p->dbl_fracl == 0)
38 			return FP_INFINITE;
39 		else
40 			return FP_NAN;
41 	}
42 
43 	return FP_NORMAL;
44 }
45 
46 int
47 __fpclassifyf(float f)
48 {
49 	struct ieee_single *p = (struct ieee_single *)&f;
50 
51 	if (p->sng_exp == 0) {
52 		if (p->sng_frac == 0)
53 			return FP_ZERO;
54 		else
55 			return FP_SUBNORMAL;
56 	}
57 
58 	if (p->sng_exp == SNG_EXP_INFNAN) {
59 		if (p->sng_frac == 0)
60 			return FP_INFINITE;
61 		else
62 			return FP_NAN;
63 	}
64 
65 	return FP_NORMAL;
66 }
67 
68 #if LDBL_MANT_DIG == 53
69 #ifdef __weak_alias
70 __weak_alias(__fpclassifyl, __fpclassify);
71 #endif /* __weak_alias */
72 #endif /* LDBL_MANT_DIG == 53 */
73