1 /* wf_log10.c -- float version of w_log10.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 /*
17  * wrapper log10f(X)
18  */
19 
20 #include "fdlibm.h"
21 #include <errno.h>
22 
23 #ifdef __STDC__
log10f(float x)24 	float log10f(float x)		/* wrapper log10f */
25 #else
26 	float log10f(x)			/* wrapper log10f */
27 	float x;
28 #endif
29 {
30 #ifdef _IEEE_LIBM
31 	return __ieee754_log10f(x);
32 #else
33 	float z;
34 	struct exception exc;
35 	z = __ieee754_log10f(x);
36 	if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
37 	if(x<=(float)0.0) {
38 #ifndef HUGE_VAL
39 #define HUGE_VAL inf
40 	    double inf = 0.0;
41 
42 	    SET_HIGH_WORD(inf,0x7ff00000);	/* set inf to infinite */
43 #endif
44 	    exc.name = "log10f";
45 	    exc.err = 0;
46 	    exc.arg1 = exc.arg2 = (double)x;
47 	    if (_LIB_VERSION == _SVID_)
48                exc.retval = -HUGE;
49 	    else
50 	       exc.retval = -HUGE_VAL;
51 	    if(x==(float)0.0) {
52 	        /* log10f(0) */
53 	        exc.type = SING;
54 	        if (_LIB_VERSION == _POSIX_)
55 	           errno = ERANGE;
56 	        else if (!matherr(&exc)) {
57 	           errno = ERANGE;
58 	        }
59 	    } else {
60 	        /* log10f(x<0) */
61 	        exc.type = DOMAIN;
62 	        if (_LIB_VERSION == _POSIX_)
63 	           errno = EDOM;
64 	        else if (!matherr(&exc)) {
65 	           errno = EDOM;
66 	        }
67                 exc.retval = nan("");
68             }
69 	    if (exc.err != 0)
70                errno = exc.err;
71             return (float)exc.retval;
72 	} else
73 	    return z;
74 #endif
75 }
76 
77 #ifdef _DOUBLE_IS_32BITS
78 
79 #ifdef __STDC__
log10(double x)80 	double log10(double x)
81 #else
82 	double log10(x)
83 	double x;
84 #endif
85 {
86 	return (double) log10f((float) x);
87 }
88 
89 #endif /* defined(_DOUBLE_IS_32BITS) */
90