xref: /netbsd-src/lib/libm/src/w_scalbf.c (revision 2a399c6883d870daece976daec6ffa7bb7f934ce)
1 /* w_scalbf.c -- float version of w_scalb.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 #include <sys/cdefs.h>
17 #if defined(LIBM_SCCS) && !defined(lint)
18 __RCSID("$NetBSD: w_scalbf.c,v 1.4 1997/10/09 11:36:04 lukem Exp $");
19 #endif
20 
21 /*
22  * wrapper scalbf(float x, float fn) is provide for
23  * passing various standard test suite. One
24  * should use scalbn() instead.
25  */
26 
27 #include "math.h"
28 #include "math_private.h"
29 
30 #include <errno.h>
31 
32 #ifdef __STDC__
33 #ifdef _SCALB_INT
34 	float scalbf(float x, int fn)		/* wrapper scalbf */
35 #else
36 	float scalbf(float x, float fn)		/* wrapper scalbf */
37 #endif
38 #else
39 	float scalbf(x,fn)			/* wrapper scalbf */
40 #ifdef _SCALB_INT
41 	float x; int fn;
42 #else
43 	float x,fn;
44 #endif
45 #endif
46 {
47 #ifdef _IEEE_LIBM
48 	return __ieee754_scalbf(x,fn);
49 #else
50 	float z;
51 	z = __ieee754_scalbf(x,fn);
52 	if(_LIB_VERSION == _IEEE_) return z;
53 	if(!(finitef(z)||isnanf(z))&&finitef(x)) {
54 	    /* scalbf overflow */
55 	    return (float)__kernel_standard((double)x,(double)fn,132);
56 	}
57 	if(z==(float)0.0&&z!=x) {
58 	    /* scalbf underflow */
59 	    return (float)__kernel_standard((double)x,(double)fn,133);
60 	}
61 #ifndef _SCALB_INT
62 	if(!finitef(fn)) errno = ERANGE;
63 #endif
64 	return z;
65 #endif
66 }
67