1 /* @(#)w_scalb.c 5.1 93/09/24 */ 2 /* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * 6 * Developed at SunPro, a Sun Microsystems, Inc. business. 7 * Permission to use, copy, modify, and distribute this 8 * software is freely granted, provided that this notice 9 * is preserved. 10 * ==================================================== 11 */ 12 13 #ifndef lint 14 static char rcsid[] = "$Id: w_scalb.c,v 1.4 1994/08/10 20:35:37 jtc Exp $"; 15 #endif 16 17 /* 18 * wrapper scalb(double x, double fn) is provide for 19 * passing various standard test suite. One 20 * should use scalbn() instead. 21 */ 22 23 #include "math.h" 24 #include "math_private.h" 25 26 #include <errno.h> 27 28 #ifdef __STDC__ 29 #ifdef _SCALB_INT 30 double scalb(double x, int fn) /* wrapper scalb */ 31 #else 32 double scalb(double x, double fn) /* wrapper scalb */ 33 #endif 34 #else 35 double scalb(x,fn) /* wrapper scalb */ 36 #ifdef _SCALB_INT 37 double x; int fn; 38 #else 39 double x,fn; 40 #endif 41 #endif 42 { 43 #ifdef _IEEE_LIBM 44 return __ieee754_scalb(x,fn); 45 #else 46 double z; 47 z = __ieee754_scalb(x,fn); 48 if(_LIB_VERSION == _IEEE_) return z; 49 if(!(finite(z)||isnan(z))&&finite(x)) { 50 return __kernel_standard(x,(double)fn,32); /* scalb overflow */ 51 } 52 if(z==0.0&&z!=x) { 53 return __kernel_standard(x,(double)fn,33); /* scalb underflow */ 54 } 55 #ifndef _SCALB_INT 56 if(!finite(fn)) errno = ERANGE; 57 #endif 58 return z; 59 #endif 60 } 61