1 /****************************************************************
2
3 The author of this software is David M. Gay.
4
5 Copyright (C) 1998 by Lucent Technologies
6 All Rights Reserved
7
8 Permission to use, copy, modify, and distribute this software and
9 its documentation for any purpose and without fee is hereby
10 granted, provided that the above copyright notice appear in all
11 copies and that both that the copyright notice and this
12 permission notice and warranty disclaimer appear in supporting
13 documentation, and that the name of Lucent or any of its entities
14 not be used in advertising or publicity pertaining to
15 distribution of the software without specific, written prior
16 permission.
17
18 LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
20 IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
21 SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
22 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
23 IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
24 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
25 THIS SOFTWARE.
26
27 ****************************************************************/
28
29 /* Please send bug reports to David M. Gay (dmg at acm dot org,
30 * with " at " changed at "@" and " dot " changed to "."). */
31
32 #include "gdtoaimp.h"
33
34 #ifdef USE_LOCALE
35 #include "locale.h"
36 #endif
37
38 int
39 #ifdef KR_headers
gethex(sp,fpi,exp,bp,sign)40 gethex(sp, fpi, exp, bp, sign)
41 CONST char **sp; FPI *fpi; Long *exp; Bigint **bp; int sign;
42 #else
43 gethex( CONST char **sp, FPI *fpi, Long *exp, Bigint **bp, int sign)
44 #endif
45 {
46 Bigint *b;
47 CONST unsigned char *decpt, *s0, *s, *s1;
48 int big, esign, havedig, irv, j, k, n, n0, nbits, up, zret;
49 ULong L, lostbits, *x;
50 Long e, e1;
51 #ifdef USE_LOCALE
52 int i;
53 #ifdef NO_LOCALE_CACHE
54 const unsigned char *decimalpoint = (unsigned char*)localeconv()->decimal_point;
55 #else
56 const unsigned char *decimalpoint;
57 static unsigned char *decimalpoint_cache;
58 if (!(s0 = decimalpoint_cache)) {
59 s0 = (unsigned char*)localeconv()->decimal_point;
60 if ((decimalpoint_cache = (char*)MALLOC(strlen(s0) + 1))) {
61 strlcpy(decimalpoint_cache, s0, strlen(s0) + 1);
62 s0 = decimalpoint_cache;
63 }
64 }
65 decimalpoint = s0;
66 #endif
67 #endif
68
69 if (!hexdig['0'])
70 hexdig_init_D2A();
71 *bp = 0;
72 havedig = 0;
73 s0 = *(CONST unsigned char **)sp + 2;
74 while(s0[havedig] == '0')
75 havedig++;
76 s0 += havedig;
77 s = s0;
78 decpt = 0;
79 zret = 0;
80 e = 0;
81 if (hexdig[*s])
82 havedig++;
83 else {
84 zret = 1;
85 #ifdef USE_LOCALE
86 for(i = 0; decimalpoint[i]; ++i) {
87 if (s[i] != decimalpoint[i])
88 goto pcheck;
89 }
90 decpt = s += i;
91 #else
92 if (*s != '.')
93 goto pcheck;
94 decpt = ++s;
95 #endif
96 if (!hexdig[*s])
97 goto pcheck;
98 while(*s == '0')
99 s++;
100 if (hexdig[*s])
101 zret = 0;
102 havedig = 1;
103 s0 = s;
104 }
105 while(hexdig[*s])
106 s++;
107 #ifdef USE_LOCALE
108 if (*s == *decimalpoint && !decpt) {
109 for(i = 1; decimalpoint[i]; ++i) {
110 if (s[i] != decimalpoint[i])
111 goto pcheck;
112 }
113 decpt = s += i;
114 #else
115 if (*s == '.' && !decpt) {
116 decpt = ++s;
117 #endif
118 while(hexdig[*s])
119 s++;
120 }/*}*/
121 if (decpt)
122 e = -(((Long)(s-decpt)) << 2);
123 pcheck:
124 s1 = s;
125 big = esign = 0;
126 switch(*s) {
127 case 'p':
128 case 'P':
129 switch(*++s) {
130 case '-':
131 esign = 1;
132 /* no break */
133 case '+':
134 s++;
135 }
136 if ((n = hexdig[*s]) == 0 || n > 0x19) {
137 s = s1;
138 break;
139 }
140 e1 = n - 0x10;
141 while((n = hexdig[*++s]) !=0 && n <= 0x19) {
142 if (e1 & 0xf8000000)
143 big = 1;
144 e1 = 10*e1 + n - 0x10;
145 }
146 if (esign)
147 e1 = -e1;
148 e += e1;
149 }
150 *sp = (char*)s;
151 if (!havedig)
152 *sp = (char*)s0 - 1;
153 if (zret)
154 return STRTOG_Zero;
155 if (big) {
156 if (esign) {
157 switch(fpi->rounding) {
158 case FPI_Round_up:
159 if (sign)
160 break;
161 goto ret_tiny;
162 case FPI_Round_down:
163 if (!sign)
164 break;
165 goto ret_tiny;
166 }
167 goto retz;
168 ret_tiny:
169 b = Balloc(0);
170 if (b == NULL)
171 return (STRTOG_NoMemory);
172 b->wds = 1;
173 b->x[0] = 1;
174 goto dret;
175 }
176 switch(fpi->rounding) {
177 case FPI_Round_near:
178 goto ovfl1;
179 case FPI_Round_up:
180 if (!sign)
181 goto ovfl1;
182 goto ret_big;
183 case FPI_Round_down:
184 if (sign)
185 goto ovfl1;
186 goto ret_big;
187 }
188 ret_big:
189 nbits = fpi->nbits;
190 n0 = n = nbits >> kshift;
191 if (nbits & kmask)
192 ++n;
193 for(j = n, k = 0; j >>= 1; ++k);
194 *bp = b = Balloc(k);
195 if (*bp == NULL)
196 return (STRTOG_NoMemory);
197 b->wds = n;
198 for(j = 0; j < n0; ++j)
199 b->x[j] = ALL_ON;
200 if (n > n0)
201 b->x[j] = ULbits >> (ULbits - (nbits & kmask));
202 *exp = fpi->emin;
203 return STRTOG_Normal | STRTOG_Inexlo;
204 }
205 n = s1 - s0 - 1;
206 for(k = 0; n > (1 << (kshift-2)) - 1; n >>= 1)
207 k++;
208 b = Balloc(k);
209 if (b == NULL)
210 return (STRTOG_NoMemory);
211 x = b->x;
212 n = 0;
213 L = 0;
214 #ifdef USE_LOCALE
215 for(i = 0; decimalpoint[i+1]; ++i);
216 #endif
217 while(s1 > s0) {
218 #ifdef USE_LOCALE
219 if (*--s1 == decimalpoint[i]) {
220 s1 -= i;
221 continue;
222 }
223 #else
224 if (*--s1 == '.')
225 continue;
226 #endif
227 if (n == ULbits) {
228 *x++ = L;
229 L = 0;
230 n = 0;
231 }
232 L |= (hexdig[*s1] & 0x0f) << n;
233 n += 4;
234 }
235 *x++ = L;
236 b->wds = n = x - b->x;
237 n = ULbits*n - hi0bits(L);
238 nbits = fpi->nbits;
239 lostbits = 0;
240 x = b->x;
241 if (n > nbits) {
242 n -= nbits;
243 if (any_on(b,n)) {
244 lostbits = 1;
245 k = n - 1;
246 if (x[k>>kshift] & 1 << (k & kmask)) {
247 lostbits = 2;
248 if (k > 0 && any_on(b,k))
249 lostbits = 3;
250 }
251 }
252 rshift(b, n);
253 e += n;
254 }
255 else if (n < nbits) {
256 n = nbits - n;
257 b = lshift(b, n);
258 if (b == NULL)
259 return (STRTOG_NoMemory);
260 e -= n;
261 x = b->x;
262 }
263 if (e > fpi->emax) {
264 ovfl:
265 Bfree(b);
266 ovfl1:
267 #ifndef NO_ERRNO
268 errno = ERANGE;
269 #endif
270 return STRTOG_Infinite | STRTOG_Overflow | STRTOG_Inexhi;
271 }
272 irv = STRTOG_Normal;
273 if (e < fpi->emin) {
274 irv = STRTOG_Denormal;
275 n = fpi->emin - e;
276 if (n >= nbits) {
277 switch (fpi->rounding) {
278 case FPI_Round_near:
279 if (n == nbits && (n < 2 || any_on(b,n-1)))
280 goto one_bit;
281 break;
282 case FPI_Round_up:
283 if (!sign)
284 goto one_bit;
285 break;
286 case FPI_Round_down:
287 if (sign) {
288 one_bit:
289 x[0] = b->wds = 1;
290 dret:
291 *bp = b;
292 *exp = fpi->emin;
293 #ifndef NO_ERRNO
294 errno = ERANGE;
295 #endif
296 return STRTOG_Denormal | STRTOG_Inexhi
297 | STRTOG_Underflow;
298 }
299 }
300 Bfree(b);
301 retz:
302 #ifndef NO_ERRNO
303 errno = ERANGE;
304 #endif
305 return STRTOG_Zero | STRTOG_Inexlo | STRTOG_Underflow;
306 }
307 k = n - 1;
308 if (lostbits)
309 lostbits = 1;
310 else if (k > 0)
311 lostbits = any_on(b,k);
312 if (x[k>>kshift] & 1 << (k & kmask))
313 lostbits |= 2;
314 nbits -= n;
315 rshift(b,n);
316 e = fpi->emin;
317 }
318 if (lostbits) {
319 up = 0;
320 switch(fpi->rounding) {
321 case FPI_Round_zero:
322 break;
323 case FPI_Round_near:
324 if (lostbits & 2
325 && (lostbits | x[0]) & 1)
326 up = 1;
327 break;
328 case FPI_Round_up:
329 up = 1 - sign;
330 break;
331 case FPI_Round_down:
332 up = sign;
333 }
334 if (up) {
335 k = b->wds;
336 b = increment(b);
337 if (b == NULL)
338 return (STRTOG_NoMemory);
339 x = b->x;
340 if (irv == STRTOG_Denormal) {
341 if (nbits == fpi->nbits - 1
342 && x[nbits >> kshift] & 1 << (nbits & kmask))
343 irv = STRTOG_Normal;
344 }
345 else if (b->wds > k
346 || ((n = nbits & kmask) !=0
347 && hi0bits(x[k-1]) < 32-n)) {
348 rshift(b,1);
349 if (++e > fpi->emax)
350 goto ovfl;
351 }
352 irv |= STRTOG_Inexhi;
353 }
354 else
355 irv |= STRTOG_Inexlo;
356 }
357 *bp = b;
358 *exp = e;
359 return irv;
360 }
361