xref: /openbsd-src/lib/libc/gen/fpclassify.c (revision 48950c12d106c85f315112191a0228d7b83b9510)
1 /*	$OpenBSD: fpclassify.c,v 1.6 2012/12/05 23:19:59 deraadt 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 /* LINTLIBRARY */
19 
20 #include <sys/types.h>
21 #include <machine/ieee.h>
22 #include <float.h>
23 #include <math.h>
24 
25 int
26 __fpclassify(double d)
27 {
28 	struct ieee_double *p = (struct ieee_double *)&d;
29 
30 	if (p->dbl_exp == 0) {
31 		if (p->dbl_frach == 0 && p->dbl_fracl == 0)
32 			return FP_ZERO;
33 		else
34 			return FP_SUBNORMAL;
35 	}
36 
37 	if (p->dbl_exp == DBL_EXP_INFNAN) {
38 		if (p->dbl_frach == 0 && p->dbl_fracl == 0)
39 			return FP_INFINITE;
40 		else
41 			return FP_NAN;
42 	}
43 
44 	return FP_NORMAL;
45 }
46 
47 int
48 __fpclassifyf(float f)
49 {
50 	struct ieee_single *p = (struct ieee_single *)&f;
51 
52 	if (p->sng_exp == 0) {
53 		if (p->sng_frac == 0)
54 			return FP_ZERO;
55 		else
56 			return FP_SUBNORMAL;
57 	}
58 
59 	if (p->sng_exp == SNG_EXP_INFNAN) {
60 		if (p->sng_frac == 0)
61 			return FP_INFINITE;
62 		else
63 			return FP_NAN;
64 	}
65 
66 	return FP_NORMAL;
67 }
68 
69 #if	LDBL_MANT_DIG == 53
70 #ifdef	lint
71 /* PROTOLIB1 */
72 int __fpclassifyl(long double);
73 #else	/* lint */
74 __weak_alias(__fpclassifyl, __fpclassify);
75 #endif	/* lint */
76 #endif	/* LDBL_MANT_DIG == 53 */
77