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 1.3 1994/02/18 02:28:05 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 25 #include <errno.h> 26 27 #ifdef __STDC__ 28 #ifdef _SCALB_INT 29 double scalb(double x, int fn) /* wrapper scalb */ 30 #else 31 double scalb(double x, double fn) /* wrapper scalb */ 32 #endif 33 #else 34 double scalb(x,fn) /* wrapper scalb */ 35 #ifdef _SCALB_INT 36 double x; int fn; 37 #else 38 double x,fn; 39 #endif 40 #endif 41 { 42 #ifdef _IEEE_LIBM 43 return __ieee754_scalb(x,fn); 44 #else 45 double z; 46 z = __ieee754_scalb(x,fn); 47 if(_LIB_VERSION == _IEEE_) return z; 48 if(!(finite(z)||isnan(z))&&finite(x)) { 49 return __kernel_standard(x,(double)fn,32); /* scalb overflow */ 50 } 51 if(z==0.0&&z!=x) { 52 return __kernel_standard(x,(double)fn,33); /* scalb underflow */ 53 } 54 #ifndef _SCALB_INT 55 if(!finite(fn)) errno = ERANGE; 56 #endif 57 return z; 58 #endif 59 } 60