blob: c9e49c67955e8ebfdd45c31915131dae456d80b8 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
/* public domain rewrite of isinf(3) */
#ifdef __osf__
#define _IEEE 1
#include <nan.h>
int
isinf(n)
double n;
{
if (IsNANorINF(n) && IsINF(n)) {
return 1;
}
else {
return 0;
}
}
#else
#include "config.h"
#if defined(HAVE_FINITE) && defined(HAVE_ISNAN)
#include <math.h>
#ifdef HAVE_IEEEFP_H
#include <ieeefp.h>
#endif
/*
* isinf may be provided only as a macro.
* ex. HP-UX, Solaris 10
* http://www.gnu.org/software/automake/manual/autoconf/Function-Portability.html
*/
#ifndef isinf
int
isinf(n)
double n;
{
return (!finite(n) && !isnan(n));
}
#endif
#else
#ifdef HAVE_STRING_H
# include <string.h>
#else
# include <strings.h>
#endif
static double zero() { return 0.0; }
static double one() { return 1.0; }
static double inf() { return one() / zero(); }
int
isinf(n)
double n;
{
static double pinf = 0.0;
static double ninf = 0.0;
if (pinf == 0.0) {
pinf = inf();
ninf = -pinf;
}
return memcmp(&n, &pinf, sizeof n) == 0
|| memcmp(&n, &ninf, sizeof n) == 0;
}
#endif
#endif
|
