POK
scalb.c
1 /*
2  * POK header
3  *
4  * The following file is a part of the POK project. Any modification should
5  * made according to the POK licence. You CANNOT use this file or a part of
6  * this file is this part of a file for your own project
7  *
8  * For more information on the POK licence, please see our LICENCE FILE
9  *
10  * Please follow the coding guidelines described in doc/CODING_GUIDELINES
11  *
12  * Copyright (c) 2007-2009 POK team
13  *
14  * Created by julien on Fri Jan 30 14:41:34 2009
15  */
16 
17 /* @(#)w_scalb.c 5.1 93/09/24 */
18 /*
19  * ====================================================
20  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
21  *
22  * Developed at SunPro, a Sun Microsystems, Inc. business.
23  * Permission to use, copy, modify, and distribute this
24  * software is freely granted, provided that this notice
25  * is preserved.
26  * ====================================================
27  */
28 
29 #ifdef POK_NEEDS_LIBMATH
30 
31 /*
32  * wrapper scalb(double x, double fn) is provide for
33  * passing various standard test suite. One
34  * should use scalbn() instead.
35  */
36 
37 #include <libm.h>
38 #include "math_private.h"
39 
40 #include <errno.h>
41 
42 #ifdef _SCALB_INT
43 double
44 scalb(double x, int fn) /* wrapper scalb */
45 #else
46 double
47 scalb(double x, double fn) /* wrapper scalb */
48 #endif
49 {
50 #ifdef _IEEE_LIBM
51  return __ieee754_scalb(x,fn);
52 #else
53  double z;
54  z = __ieee754_scalb(x,fn);
55  if(_LIB_VERSION == _IEEE_) return z;
56  if(!(finite(z)||isnan(z))&&finite(x)) {
57  return __kernel_standard(x,(double)fn,32); /* scalb overflow */
58  }
59  if(z==0.0&&z!=x) {
60  return __kernel_standard(x,(double)fn,33); /* scalb underflow */
61  }
62 #ifndef _SCALB_INT
63  if(!finite(fn)) errno = POK_ERRNO_ERANGE;
64 #endif
65  return z;
66 #endif
67 }
68 
69 #endif