1 /* $NetBSD: hexnan.c,v 1.5 2011/03/21 04:52:09 christos 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
34 #include "gdtoaimp.h"
35
36 static void
37 #ifdef KR_headers
L_shift(x,x1,i)38 L_shift(x, x1, i) ULong *x; ULong *x1; int i;
39 #else
40 L_shift(ULong *x, ULong *x1, int i)
41 #endif
42 {
43 int j;
44
45 i = 8 - i;
46 i <<= 2;
47 j = ULbits - i;
48 do {
49 *x |= x[1] << j;
50 x[1] >>= i;
51 } while(++x < x1);
52 }
53
54 int
55 #ifdef KR_headers
hexnan(sp,fpi,x0)56 hexnan(sp, fpi, x0)
57 CONST char **sp; CONST FPI *fpi; ULong *x0;
58 #else
59 hexnan( CONST char **sp, CONST FPI *fpi, ULong *x0)
60 #endif
61 {
62 ULong c, h, *x, *x1, *xe;
63 CONST char *s;
64 int havedig, hd0, i, nbits;
65
66 if (!hexdig['0'])
67 hexdig_init_D2A();
68 nbits = fpi->nbits;
69 x = x0 + ((unsigned int)nbits >> kshift);
70 if (nbits & kmask)
71 x++;
72 *--x = 0;
73 x1 = xe = x;
74 havedig = hd0 = i = 0;
75 s = *sp;
76 /* allow optional initial 0x or 0X */
77 while((c = *(CONST unsigned char*)(s+1)) && c <= ' ')
78 ++s;
79 if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
80 && *(CONST unsigned char*)(s+3) > ' ')
81 s += 2;
82 while((c = *(CONST unsigned char*)++s) != '\0') {
83 if (!(h = hexdig[c])) {
84 if (c <= ' ') {
85 if (hd0 < havedig) {
86 if (x < x1 && i < 8)
87 L_shift(x, x1, i);
88 if (x <= x0) {
89 i = 8;
90 continue;
91 }
92 hd0 = havedig;
93 *--x = 0;
94 x1 = x;
95 i = 0;
96 }
97 while(*(CONST unsigned char*)(s+1) <= ' ')
98 ++s;
99 if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X')
100 && *(CONST unsigned char*)(s+3) > ' ')
101 s += 2;
102 continue;
103 }
104 if (/*(*/ c == ')' && havedig) {
105 *sp = s + 1;
106 break;
107 }
108 #ifndef GDTOA_NON_PEDANTIC_NANCHECK
109 do {
110 if (/*(*/ c == ')') {
111 *sp = s + 1;
112 break;
113 }
114 } while((c = *++s) != '\0');
115 #endif
116 return STRTOG_NaN;
117 }
118 havedig++;
119 if (++i > 8) {
120 if (x <= x0)
121 continue;
122 i = 1;
123 *--x = 0;
124 }
125 *x = (*x << 4) | (h & 0xf);
126 }
127 if (!havedig)
128 return STRTOG_NaN;
129 if (x < x1 && i < 8)
130 L_shift(x, x1, i);
131 if (x > x0) {
132 x1 = x0;
133 do *x1++ = *x++;
134 while(x <= xe);
135 do *x1++ = 0;
136 while(x1 <= xe);
137 }
138 else {
139 /* truncate high-order word if necessary */
140 if ( (i = nbits & (ULbits-1)) !=0)
141 *xe &= ((ULong)0xffffffff) >> (ULbits - i);
142 }
143 for(x1 = xe;; --x1) {
144 if (*x1 != 0)
145 break;
146 if (x1 == x0) {
147 *x1 = 1;
148 break;
149 }
150 }
151 return STRTOG_NaNbits;
152 }
153