summaryrefslogtreecommitdiff
path: root/lib/libm/src/w_log.c
blob: 9ab1880e08c8b15d8a0a33098c1363189c6cc6d9 (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
/* @(#)w_log.c 5.1 93/09/24 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice
 * is preserved.
 * ====================================================
 */

#include <sys/cdefs.h>
#if defined(LIBM_SCCS) && !defined(lint)
__RCSID("$NetBSD: w_log.c,v 1.10 2007/08/20 16:01:40 drochner Exp $");
#endif

/*
 * wrapper log(x)
 */

#include "namespace.h"
#include "math.h"
#include "math_private.h"

#ifdef __weak_alias
__weak_alias(log, _log)
#endif

double
log(double x)		/* wrapper log */
{
#ifdef _IEEE_LIBM
	return __ieee754_log(x);
#else
	double z;
	z = __ieee754_log(x);
	if(_LIB_VERSION == _IEEE_ || isnan(x) || x > 0.0) return z;
	if(x==0.0)
	    return __kernel_standard(x,x,16); /* log(0) */
	else
	    return __kernel_standard(x,x,17); /* log(x<0) */
#endif
}