xref: /netbsd-src/lib/libm/src/w_logf.c (revision 76dfffe33547c37f8bdd446e3e4ab0f3c16cea4b)
1 /* w_logf.c -- float version of w_log.c.
2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3  */
4 
5 /*
6  * ====================================================
7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8  *
9  * Developed at SunPro, a Sun Microsystems, Inc. business.
10  * Permission to use, copy, modify, and distribute this
11  * software is freely granted, provided that this notice
12  * is preserved.
13  * ====================================================
14  */
15 
16 #if defined(LIBM_SCCS) && !defined(lint)
17 static char rcsid[] = "$NetBSD: w_logf.c,v 1.3 1995/05/10 20:49:40 jtc Exp $";
18 #endif
19 
20 /*
21  * wrapper logf(x)
22  */
23 
24 #include "math.h"
25 #include "math_private.h"
26 
27 
28 #ifdef __STDC__
29 	float logf(float x)		/* wrapper logf */
30 #else
31 	float logf(x)			/* wrapper logf */
32 	float x;
33 #endif
34 {
35 #ifdef _IEEE_LIBM
36 	return __ieee754_logf(x);
37 #else
38 	float z;
39 	z = __ieee754_logf(x);
40 	if(_LIB_VERSION == _IEEE_ || isnanf(x) || x > (float)0.0) return z;
41 	if(x==(float)0.0)
42 	    /* logf(0) */
43 	    return (float)__kernel_standard((double)x,(double)x,116);
44 	else
45 	    /* logf(x<0) */
46 	    return (float)__kernel_standard((double)x,(double)x,117);
47 #endif
48 }
49