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glibc  2.9
w_logf.c
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00001 /* w_logf.c -- float version of w_log.c.
00002  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
00003  */
00004 
00005 /*
00006  * ====================================================
00007  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
00008  *
00009  * Developed at SunPro, a Sun Microsystems, Inc. business.
00010  * Permission to use, copy, modify, and distribute this
00011  * software is freely granted, provided that this notice 
00012  * is preserved.
00013  * ====================================================
00014  */
00015 
00016 #if defined(LIBM_SCCS) && !defined(lint)
00017 static char rcsid[] = "$NetBSD: w_logf.c,v 1.3 1995/05/10 20:49:40 jtc Exp $";
00018 #endif
00019 
00020 /*
00021  * wrapper logf(x)
00022  */
00023 
00024 #include <math.h>
00025 #include "math_private.h"
00026 
00027 
00028 #ifdef __STDC__
00029        float __logf(float x)              /* wrapper logf */
00030 #else
00031        float __logf(x)                    /* wrapper logf */
00032        float x;
00033 #endif
00034 {
00035 #ifdef _IEEE_LIBM
00036        return __ieee754_logf(x);
00037 #else
00038        float z;
00039        z = __ieee754_logf(x);
00040        if(_LIB_VERSION == _IEEE_ || __isnanf(x) || x > (float)0.0) return z;
00041        if(x==(float)0.0)
00042            /* logf(0) */
00043            return (float)__kernel_standard((double)x,(double)x,116);
00044        else 
00045            /* logf(x<0) */
00046            return (float)__kernel_standard((double)x,(double)x,117);
00047 #endif
00048 }
00049 weak_alias (__logf, logf)