1 /* $NetBSD: hexnan.c,v 1.3 2006/03/11 18:38:14 kleink Exp $ */
2
3 /****************************************************************
4
5 The author of this software is David M. Gay.
6
7 Copyright (C) 2000 by Lucent Technologies
8 All Rights Reserved
9
10 Permission to use, copy, modify, and distribute this software and
11 its documentation for any purpose and without fee is hereby
12 granted, provided that the above copyright notice appear in all
13 copies and that both that the copyright notice and this
14 permission notice and warranty disclaimer appear in supporting
15 documentation, and that the name of Lucent or any of its entities
16 not be used in advertising or publicity pertaining to
17 distribution of the software without specific, written prior
18 permission.
19
20 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
21 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
22 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
23 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
24 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
25 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
26 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
27 THIS SOFTWARE.
28
29 ****************************************************************/
30
31 /* Please send bug reports to David M. Gay (dmg at acm dot org,
32 * with " at " changed at "@" and " dot " changed to "."). */
33 #include <LibConfig.h>
34
35 #include "gdtoaimp.h"
36
37 static void
38 #ifdef KR_headers
L_shift(x,x1,i)39 L_shift(x, x1, i) ULong *x; ULong *x1; int i;
40 #else
41 L_shift(ULong *x, ULong *x1, int i)
42 #endif
43 {
44 int j;
45
46 i = 8 - i;
47 i <<= 2;
48 j = ULbits - i;
49 do {
50 *x |= x[1] << j;
51 x[1] >>= i;
52 } while(++x < x1);
53 }
54
55 int
56 #ifdef KR_headers
hexnan(sp,fpi,x0)57 hexnan(sp, fpi, x0)
58 CONST char **sp; CONST FPI *fpi; ULong *x0;
59 #else
60 hexnan( CONST char **sp, CONST FPI *fpi, ULong *x0)
61 #endif
62 {
63 ULong c, h, *x, *x1, *xe;
64 CONST char *s;
65 int havedig, hd0, i, nbits;
66
67 if (!hexdig['0'])
68 hexdig_init_D2A();
69 nbits = fpi->nbits;
70 x = x0 + ((unsigned int)nbits >> kshift);
71 if (nbits & kmask)
72 x++;
73 *--x = 0;
74 x1 = xe = x;
75 havedig = hd0 = i = 0;
76 s = *sp;
77 while((c = *(CONST unsigned char*)++s) != 0) {
78 if ((h = hexdig[c]) == 0) {
79 if (c <= ' ') {
80 if (hd0 < havedig) {
81 if (x < x1 && i < 8)
82 L_shift(x, x1, i);
83 if (x <= x0) {
84 i = 8;
85 continue;
86 }
87 hd0 = havedig;
88 *--x = 0;
89 x1 = x;
90 i = 0;
91 }
92 continue;
93 }
94 if (/*(*/ c == ')' && havedig) {
95 *sp = s + 1;
96 break;
97 }
98 return STRTOG_NaN;
99 }
100 havedig++;
101 if (++i > 8) {
102 if (x <= x0)
103 continue;
104 i = 1;
105 *--x = 0;
106 }
107 *x = (*x << 4) | (h & 0xf);
108 }
109 if (!havedig)
110 return STRTOG_NaN;
111 if (x < x1 && i < 8)
112 L_shift(x, x1, i);
113 if (x > x0) {
114 x1 = x0;
115 do *x1++ = *x++;
116 while(x <= xe);
117 do *x1++ = 0;
118 while(x1 <= xe);
119 }
120 else {
121 /* truncate high-order word if necessary */
122 if ( (i = nbits & (ULbits-1)) !=0)
123 *xe &= ((ULong)0xffffffff) >> (ULbits - i);
124 }
125 for(x1 = xe;; --x1) {
126 if (*x1 != 0)
127 break;
128 if (x1 == x0) {
129 *x1 = 1;
130 break;
131 }
132 }
133 return STRTOG_NaNbits;
134 }
135