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2aa62f2b | 1 | /* $NetBSD: gethex.c,v 1.3.14.1 2008/04/08 21:10:55 jdc Exp $ */\r |
2 | \r | |
3 | /****************************************************************\r | |
4 | \r | |
5 | The author of this software is David M. Gay.\r | |
6 | \r | |
7 | Copyright (C) 1998 by Lucent Technologies\r | |
8 | All Rights Reserved\r | |
9 | \r | |
10 | Permission to use, copy, modify, and distribute this software and\r | |
11 | its documentation for any purpose and without fee is hereby\r | |
12 | granted, provided that the above copyright notice appear in all\r | |
13 | copies and that both that the copyright notice and this\r | |
14 | permission notice and warranty disclaimer appear in supporting\r | |
15 | documentation, and that the name of Lucent or any of its entities\r | |
16 | not be used in advertising or publicity pertaining to\r | |
17 | distribution of the software without specific, written prior\r | |
18 | permission.\r | |
19 | \r | |
20 | LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,\r | |
21 | INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.\r | |
22 | IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY\r | |
23 | SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES\r | |
24 | WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER\r | |
25 | IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,\r | |
26 | ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF\r | |
27 | THIS SOFTWARE.\r | |
28 | \r | |
29 | ****************************************************************/\r | |
30 | \r | |
31 | /* Please send bug reports to David M. Gay (dmg at acm dot org,\r | |
32 | * with " at " changed at "@" and " dot " changed to "."). */\r | |
33 | #include <LibConfig.h>\r | |
34 | \r | |
35 | #include "gdtoaimp.h"\r | |
36 | \r | |
37 | #ifdef USE_LOCALE\r | |
38 | #include "locale.h"\r | |
39 | #endif\r | |
40 | \r | |
41 | int\r | |
42 | gethex( CONST char **sp, CONST FPI *fpi, Long *expt, Bigint **bp, int sign)\r | |
43 | {\r | |
44 | Bigint *b;\r | |
45 | CONST unsigned char *decpt, *s0, *s, *s1;\r | |
46 | int esign, havedig, irv, k, n, nbits, up, zret;\r | |
47 | ULong L, lostbits, *x;\r | |
48 | Long e, e1;\r | |
49 | #ifdef USE_LOCALE\r | |
50 | unsigned char decimalpoint = *localeconv()->decimal_point;\r | |
51 | #else\r | |
52 | #define decimalpoint '.'\r | |
53 | #endif\r | |
54 | \r | |
55 | if (!hexdig['0'])\r | |
56 | hexdig_init_D2A();\r | |
57 | havedig = 0;\r | |
58 | s0 = *(CONST unsigned char **)sp + 2;\r | |
59 | while(s0[havedig] == '0')\r | |
60 | havedig++;\r | |
61 | s0 += havedig;\r | |
62 | s = s0;\r | |
63 | decpt = 0;\r | |
64 | zret = 0;\r | |
65 | e = 0;\r | |
66 | if (!hexdig[*s]) {\r | |
67 | zret = 1;\r | |
68 | if (*s != decimalpoint)\r | |
69 | goto pcheck;\r | |
70 | decpt = ++s;\r | |
71 | if (!hexdig[*s])\r | |
72 | goto pcheck;\r | |
73 | while(*s == '0')\r | |
74 | s++;\r | |
75 | if (hexdig[*s])\r | |
76 | zret = 0;\r | |
77 | havedig = 1;\r | |
78 | s0 = s;\r | |
79 | }\r | |
80 | while(hexdig[*s])\r | |
81 | s++;\r | |
82 | if (*s == decimalpoint && !decpt) {\r | |
83 | decpt = ++s;\r | |
84 | while(hexdig[*s])\r | |
85 | s++;\r | |
86 | }\r | |
87 | if (decpt)\r | |
88 | e = -(((Long)(s-decpt)) << 2);\r | |
89 | pcheck:\r | |
90 | s1 = s;\r | |
91 | switch(*s) {\r | |
92 | case 'p':\r | |
93 | case 'P':\r | |
94 | esign = 0;\r | |
95 | switch(*++s) {\r | |
96 | case '-':\r | |
97 | esign = 1;\r | |
98 | /* FALLTHROUGH */\r | |
99 | case '+':\r | |
100 | s++;\r | |
101 | }\r | |
102 | if ((n = hexdig[*s]) == 0 || n > 0x19) {\r | |
103 | s = s1;\r | |
104 | break;\r | |
105 | }\r | |
106 | e1 = n - 0x10;\r | |
107 | while((n = hexdig[*++s]) !=0 && n <= 0x19)\r | |
108 | e1 = 10*e1 + n - 0x10;\r | |
109 | if (esign)\r | |
110 | e1 = -e1;\r | |
111 | e += e1;\r | |
112 | }\r | |
113 | *sp = __UNCONST(s);\r | |
114 | if (zret)\r | |
115 | return havedig ? STRTOG_Zero : STRTOG_NoNumber;\r | |
116 | n = (int)(s1 - s0 - 1);\r | |
117 | for(k = 0; n > 7; n = (unsigned int)n >> 1)\r | |
118 | k++;\r | |
119 | b = Balloc(k);\r | |
120 | if (b == NULL)\r | |
121 | return STRTOG_NoMemory;\r | |
122 | x = b->x;\r | |
123 | n = 0;\r | |
124 | L = 0;\r | |
125 | while(s1 > s0) {\r | |
126 | if (*--s1 == decimalpoint)\r | |
127 | continue;\r | |
128 | if (n == 32) {\r | |
129 | *x++ = L;\r | |
130 | L = 0;\r | |
131 | n = 0;\r | |
132 | }\r | |
133 | L |= (hexdig[*s1] & 0x0f) << n;\r | |
134 | n += 4;\r | |
135 | }\r | |
136 | *x++ = L;\r | |
137 | b->wds = n = (int)(x - b->x);\r | |
138 | n = 32*n - hi0bits(L);\r | |
139 | nbits = fpi->nbits;\r | |
140 | lostbits = 0;\r | |
141 | x = b->x;\r | |
142 | if (n > nbits) {\r | |
143 | n -= nbits;\r | |
144 | if (any_on(b,n)) {\r | |
145 | lostbits = 1;\r | |
146 | k = n - 1;\r | |
147 | if (x[(unsigned int)k>>kshift] & 1 << (k & kmask)) {\r | |
148 | lostbits = 2;\r | |
149 | if (k > 1 && any_on(b,k-1))\r | |
150 | lostbits = 3;\r | |
151 | }\r | |
152 | }\r | |
153 | rshift(b, n);\r | |
154 | e += n;\r | |
155 | }\r | |
156 | else if (n < nbits) {\r | |
157 | n = nbits - n;\r | |
158 | b = lshift(b, n);\r | |
159 | if (b == NULL)\r | |
160 | return STRTOG_NoMemory;\r | |
161 | e -= n;\r | |
162 | x = b->x;\r | |
163 | }\r | |
164 | if (e > fpi->emax) {\r | |
165 | ovfl:\r | |
166 | Bfree(b);\r | |
167 | *bp = 0;\r | |
168 | return STRTOG_Infinite | STRTOG_Overflow | STRTOG_Inexhi;\r | |
169 | }\r | |
170 | irv = STRTOG_Normal;\r | |
171 | if (e < fpi->emin) {\r | |
172 | irv = STRTOG_Denormal;\r | |
173 | n = fpi->emin - e;\r | |
174 | if (n >= nbits) {\r | |
175 | switch (fpi->rounding) {\r | |
176 | case FPI_Round_near:\r | |
177 | if (n == nbits && (n < 2 || any_on(b,n-1)))\r | |
178 | goto one_bit;\r | |
179 | break;\r | |
180 | case FPI_Round_up:\r | |
181 | if (!sign)\r | |
182 | goto one_bit;\r | |
183 | break;\r | |
184 | case FPI_Round_down:\r | |
185 | if (sign) {\r | |
186 | one_bit:\r | |
187 | *expt = fpi->emin;\r | |
188 | x[0] = b->wds = 1;\r | |
189 | *bp = b;\r | |
190 | return STRTOG_Denormal | STRTOG_Inexhi\r | |
191 | | STRTOG_Underflow;\r | |
192 | }\r | |
193 | }\r | |
194 | Bfree(b);\r | |
195 | *bp = 0;\r | |
196 | return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow;\r | |
197 | }\r | |
198 | k = n - 1;\r | |
199 | if (lostbits)\r | |
200 | lostbits = 1;\r | |
201 | else if (k > 0)\r | |
202 | lostbits = any_on(b,k);\r | |
203 | if (x[(unsigned int)k>>kshift] & 1 << (k & kmask))\r | |
204 | lostbits |= 2;\r | |
205 | nbits -= n;\r | |
206 | rshift(b,n);\r | |
207 | e = fpi->emin;\r | |
208 | }\r | |
209 | if (lostbits) {\r | |
210 | up = 0;\r | |
211 | switch(fpi->rounding) {\r | |
212 | case FPI_Round_zero:\r | |
213 | break;\r | |
214 | case FPI_Round_near:\r | |
215 | if (lostbits & 2\r | |
216 | && (lostbits & 1) | (x[0] & 1))\r | |
217 | up = 1;\r | |
218 | break;\r | |
219 | case FPI_Round_up:\r | |
220 | up = 1 - sign;\r | |
221 | break;\r | |
222 | case FPI_Round_down:\r | |
223 | up = sign;\r | |
224 | }\r | |
225 | if (up) {\r | |
226 | k = b->wds;\r | |
227 | b = increment(b);\r | |
228 | x = b->x;\r | |
229 | if (irv == STRTOG_Denormal) {\r | |
230 | if (nbits == fpi->nbits - 1\r | |
231 | && x[(unsigned int)nbits >> kshift] & 1 << (nbits & kmask))\r | |
232 | irv = STRTOG_Normal;\r | |
233 | }\r | |
234 | else if (b->wds > k\r | |
235 | || ((n = nbits & kmask) !=0\r | |
236 | && hi0bits(x[k-1]) < 32-n)) {\r | |
237 | rshift(b,1);\r | |
238 | if (++e > fpi->emax)\r | |
239 | goto ovfl;\r | |
240 | }\r | |
241 | irv |= STRTOG_Inexhi;\r | |
242 | }\r | |
243 | else\r | |
244 | irv |= STRTOG_Inexlo;\r | |
245 | }\r | |
246 | *bp = b;\r | |
247 | *expt = e;\r | |
248 | return irv;\r | |
249 | }\r |