source: trunk/sys/libm/w_scalb.c @ 128

/* @(#)w_scalb.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.
 * ====================================================
 */

/*
 * wrapper scalb(double x, double fn) is provide for
 * passing various standard test suite. One 
 * should use scalbn() instead.
 */

#include <libm/fdlibm.h>

#include <errno.h>

#ifdef __STDC__
#ifdef _SCALB_INT
        double scalb(double x, int fn)          /* wrapper scalb */
#else
        double scalb(double x, double fn)       /* wrapper scalb */
#endif
#else
        double scalb(x,fn)                      /* wrapper scalb */
#ifdef _SCALB_INT
        double x; int fn;
#else
        double x,fn;
#endif
#endif
{
#ifdef _IEEE_LIBM
        return __ieee754_scalb(x,fn);
#else
        double z;
        z = __ieee754_scalb(x,fn);
        if(_LIB_VERSION == _IEEE_) return z;
        if(!(finite(z)||isnan(z))&&finite(x)) {
            return __kernel_standard(x,(double)fn,32); /* scalb overflow */
        }
        if(z==0.0&&z!=x) {
            return __kernel_standard(x,(double)fn,33); /* scalb underflow */
        } 
#ifndef _SCALB_INT
        if(!finite(fn)) errno = ERANGE;
#endif
        return z;
#endif 
}