Update copyright years in .h files. Also, in .pl
[p5sagit/p5-mst-13.2.git] / numeric.c
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98994639 1/* numeric.c
2 *
4bb101f2 3 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999,
54ca4ee7 4 * 2000, 2001, 2002, 2003, 2004, 2005, 2006, by Larry Wall and others
98994639 5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
8 *
9 */
10
11/*
12 * "That only makes eleven (plus one mislaid) and not fourteen, unless
13 * wizards count differently to other people."
14 */
15
ccfc67b7 16/*
17=head1 Numeric functions
166f8a29 18
19This file contains all the stuff needed by perl for manipulating numeric
20values, including such things as replacements for the OS's atof() function
21
22=cut
23
ccfc67b7 24*/
25
98994639 26#include "EXTERN.h"
27#define PERL_IN_NUMERIC_C
28#include "perl.h"
29
30U32
31Perl_cast_ulong(pTHX_ NV f)
32{
96a5add6 33 PERL_UNUSED_CONTEXT;
98994639 34 if (f < 0.0)
35 return f < I32_MIN ? (U32) I32_MIN : (U32)(I32) f;
36 if (f < U32_MAX_P1) {
37#if CASTFLAGS & 2
38 if (f < U32_MAX_P1_HALF)
39 return (U32) f;
40 f -= U32_MAX_P1_HALF;
41 return ((U32) f) | (1 + U32_MAX >> 1);
42#else
43 return (U32) f;
44#endif
45 }
46 return f > 0 ? U32_MAX : 0 /* NaN */;
47}
48
49I32
50Perl_cast_i32(pTHX_ NV f)
51{
96a5add6 52 PERL_UNUSED_CONTEXT;
98994639 53 if (f < I32_MAX_P1)
54 return f < I32_MIN ? I32_MIN : (I32) f;
55 if (f < U32_MAX_P1) {
56#if CASTFLAGS & 2
57 if (f < U32_MAX_P1_HALF)
58 return (I32)(U32) f;
59 f -= U32_MAX_P1_HALF;
60 return (I32)(((U32) f) | (1 + U32_MAX >> 1));
61#else
62 return (I32)(U32) f;
63#endif
64 }
65 return f > 0 ? (I32)U32_MAX : 0 /* NaN */;
66}
67
68IV
69Perl_cast_iv(pTHX_ NV f)
70{
96a5add6 71 PERL_UNUSED_CONTEXT;
98994639 72 if (f < IV_MAX_P1)
73 return f < IV_MIN ? IV_MIN : (IV) f;
74 if (f < UV_MAX_P1) {
75#if CASTFLAGS & 2
76 /* For future flexibility allowing for sizeof(UV) >= sizeof(IV) */
77 if (f < UV_MAX_P1_HALF)
78 return (IV)(UV) f;
79 f -= UV_MAX_P1_HALF;
80 return (IV)(((UV) f) | (1 + UV_MAX >> 1));
81#else
82 return (IV)(UV) f;
83#endif
84 }
85 return f > 0 ? (IV)UV_MAX : 0 /* NaN */;
86}
87
88UV
89Perl_cast_uv(pTHX_ NV f)
90{
96a5add6 91 PERL_UNUSED_CONTEXT;
98994639 92 if (f < 0.0)
93 return f < IV_MIN ? (UV) IV_MIN : (UV)(IV) f;
94 if (f < UV_MAX_P1) {
95#if CASTFLAGS & 2
96 if (f < UV_MAX_P1_HALF)
97 return (UV) f;
98 f -= UV_MAX_P1_HALF;
99 return ((UV) f) | (1 + UV_MAX >> 1);
100#else
101 return (UV) f;
102#endif
103 }
104 return f > 0 ? UV_MAX : 0 /* NaN */;
105}
106
53305cf1 107/*
108=for apidoc grok_bin
98994639 109
53305cf1 110converts a string representing a binary number to numeric form.
111
112On entry I<start> and I<*len> give the string to scan, I<*flags> gives
113conversion flags, and I<result> should be NULL or a pointer to an NV.
114The scan stops at the end of the string, or the first invalid character.
7b667b5f 115Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an
116invalid character will also trigger a warning.
117On return I<*len> is set to the length of the scanned string,
118and I<*flags> gives output flags.
53305cf1 119
7fc63493 120If the value is <= C<UV_MAX> it is returned as a UV, the output flags are clear,
53305cf1 121and nothing is written to I<*result>. If the value is > UV_MAX C<grok_bin>
122returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags,
123and writes the value to I<*result> (or the value is discarded if I<result>
124is NULL).
125
7b667b5f 126The binary number may optionally be prefixed with "0b" or "b" unless
a4c04bdc 127C<PERL_SCAN_DISALLOW_PREFIX> is set in I<*flags> on entry. If
128C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the binary
53305cf1 129number may use '_' characters to separate digits.
130
131=cut
132 */
133
134UV
7fc63493 135Perl_grok_bin(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) {
53305cf1 136 const char *s = start;
137 STRLEN len = *len_p;
138 UV value = 0;
139 NV value_nv = 0;
140
141 const UV max_div_2 = UV_MAX / 2;
585ec06d 142 const bool allow_underscores = (bool)(*flags & PERL_SCAN_ALLOW_UNDERSCORES);
53305cf1 143 bool overflowed = FALSE;
7fc63493 144 char bit;
53305cf1 145
a4c04bdc 146 if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) {
147 /* strip off leading b or 0b.
148 for compatibility silently suffer "b" and "0b" as valid binary
149 numbers. */
150 if (len >= 1) {
151 if (s[0] == 'b') {
152 s++;
153 len--;
154 }
155 else if (len >= 2 && s[0] == '0' && s[1] == 'b') {
156 s+=2;
157 len-=2;
158 }
159 }
53305cf1 160 }
161
7fc63493 162 for (; len-- && (bit = *s); s++) {
53305cf1 163 if (bit == '0' || bit == '1') {
164 /* Write it in this wonky order with a goto to attempt to get the
165 compiler to make the common case integer-only loop pretty tight.
166 With gcc seems to be much straighter code than old scan_bin. */
167 redo:
168 if (!overflowed) {
169 if (value <= max_div_2) {
170 value = (value << 1) | (bit - '0');
171 continue;
172 }
173 /* Bah. We're just overflowed. */
174 if (ckWARN_d(WARN_OVERFLOW))
9014280d 175 Perl_warner(aTHX_ packWARN(WARN_OVERFLOW),
53305cf1 176 "Integer overflow in binary number");
177 overflowed = TRUE;
178 value_nv = (NV) value;
179 }
180 value_nv *= 2.0;
98994639 181 /* If an NV has not enough bits in its mantissa to
d1be9408 182 * represent a UV this summing of small low-order numbers
98994639 183 * is a waste of time (because the NV cannot preserve
184 * the low-order bits anyway): we could just remember when
53305cf1 185 * did we overflow and in the end just multiply value_nv by the
98994639 186 * right amount. */
53305cf1 187 value_nv += (NV)(bit - '0');
188 continue;
189 }
190 if (bit == '_' && len && allow_underscores && (bit = s[1])
191 && (bit == '0' || bit == '1'))
98994639 192 {
193 --len;
194 ++s;
53305cf1 195 goto redo;
98994639 196 }
94dd8549 197 if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT) && ckWARN(WARN_DIGIT))
9014280d 198 Perl_warner(aTHX_ packWARN(WARN_DIGIT),
53305cf1 199 "Illegal binary digit '%c' ignored", *s);
200 break;
98994639 201 }
53305cf1 202
203 if ( ( overflowed && value_nv > 4294967295.0)
98994639 204#if UVSIZE > 4
53305cf1 205 || (!overflowed && value > 0xffffffff )
98994639 206#endif
207 ) {
208 if (ckWARN(WARN_PORTABLE))
9014280d 209 Perl_warner(aTHX_ packWARN(WARN_PORTABLE),
53305cf1 210 "Binary number > 0b11111111111111111111111111111111 non-portable");
211 }
212 *len_p = s - start;
213 if (!overflowed) {
214 *flags = 0;
215 return value;
98994639 216 }
53305cf1 217 *flags = PERL_SCAN_GREATER_THAN_UV_MAX;
218 if (result)
219 *result = value_nv;
220 return UV_MAX;
98994639 221}
222
53305cf1 223/*
224=for apidoc grok_hex
225
226converts a string representing a hex number to numeric form.
227
228On entry I<start> and I<*len> give the string to scan, I<*flags> gives
229conversion flags, and I<result> should be NULL or a pointer to an NV.
7b667b5f 230The scan stops at the end of the string, or the first invalid character.
231Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an
232invalid character will also trigger a warning.
233On return I<*len> is set to the length of the scanned string,
234and I<*flags> gives output flags.
53305cf1 235
236If the value is <= UV_MAX it is returned as a UV, the output flags are clear,
237and nothing is written to I<*result>. If the value is > UV_MAX C<grok_hex>
238returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags,
239and writes the value to I<*result> (or the value is discarded if I<result>
240is NULL).
241
d1be9408 242The hex number may optionally be prefixed with "0x" or "x" unless
a4c04bdc 243C<PERL_SCAN_DISALLOW_PREFIX> is set in I<*flags> on entry. If
244C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the hex
53305cf1 245number may use '_' characters to separate digits.
246
247=cut
248 */
249
250UV
7fc63493 251Perl_grok_hex(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) {
27da23d5 252 dVAR;
53305cf1 253 const char *s = start;
254 STRLEN len = *len_p;
255 UV value = 0;
256 NV value_nv = 0;
257
258 const UV max_div_16 = UV_MAX / 16;
585ec06d 259 const bool allow_underscores = (bool)(*flags & PERL_SCAN_ALLOW_UNDERSCORES);
53305cf1 260 bool overflowed = FALSE;
98994639 261
a4c04bdc 262 if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) {
263 /* strip off leading x or 0x.
264 for compatibility silently suffer "x" and "0x" as valid hex numbers.
265 */
266 if (len >= 1) {
267 if (s[0] == 'x') {
268 s++;
269 len--;
270 }
271 else if (len >= 2 && s[0] == '0' && s[1] == 'x') {
272 s+=2;
273 len-=2;
274 }
275 }
98994639 276 }
277
278 for (; len-- && *s; s++) {
a3b680e6 279 const char *hexdigit = strchr(PL_hexdigit, *s);
53305cf1 280 if (hexdigit) {
281 /* Write it in this wonky order with a goto to attempt to get the
282 compiler to make the common case integer-only loop pretty tight.
283 With gcc seems to be much straighter code than old scan_hex. */
284 redo:
285 if (!overflowed) {
286 if (value <= max_div_16) {
287 value = (value << 4) | ((hexdigit - PL_hexdigit) & 15);
288 continue;
289 }
290 /* Bah. We're just overflowed. */
291 if (ckWARN_d(WARN_OVERFLOW))
9014280d 292 Perl_warner(aTHX_ packWARN(WARN_OVERFLOW),
53305cf1 293 "Integer overflow in hexadecimal number");
294 overflowed = TRUE;
295 value_nv = (NV) value;
296 }
297 value_nv *= 16.0;
298 /* If an NV has not enough bits in its mantissa to
d1be9408 299 * represent a UV this summing of small low-order numbers
53305cf1 300 * is a waste of time (because the NV cannot preserve
301 * the low-order bits anyway): we could just remember when
302 * did we overflow and in the end just multiply value_nv by the
303 * right amount of 16-tuples. */
304 value_nv += (NV)((hexdigit - PL_hexdigit) & 15);
305 continue;
306 }
307 if (*s == '_' && len && allow_underscores && s[1]
e1ec3a88 308 && (hexdigit = strchr(PL_hexdigit, s[1])))
98994639 309 {
310 --len;
311 ++s;
53305cf1 312 goto redo;
98994639 313 }
94dd8549 314 if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT) && ckWARN(WARN_DIGIT))
9014280d 315 Perl_warner(aTHX_ packWARN(WARN_DIGIT),
53305cf1 316 "Illegal hexadecimal digit '%c' ignored", *s);
317 break;
318 }
319
320 if ( ( overflowed && value_nv > 4294967295.0)
321#if UVSIZE > 4
322 || (!overflowed && value > 0xffffffff )
323#endif
324 ) {
325 if (ckWARN(WARN_PORTABLE))
9014280d 326 Perl_warner(aTHX_ packWARN(WARN_PORTABLE),
53305cf1 327 "Hexadecimal number > 0xffffffff non-portable");
328 }
329 *len_p = s - start;
330 if (!overflowed) {
331 *flags = 0;
332 return value;
333 }
334 *flags = PERL_SCAN_GREATER_THAN_UV_MAX;
335 if (result)
336 *result = value_nv;
337 return UV_MAX;
338}
339
340/*
341=for apidoc grok_oct
342
7b667b5f 343converts a string representing an octal number to numeric form.
344
345On entry I<start> and I<*len> give the string to scan, I<*flags> gives
346conversion flags, and I<result> should be NULL or a pointer to an NV.
347The scan stops at the end of the string, or the first invalid character.
348Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an
349invalid character will also trigger a warning.
350On return I<*len> is set to the length of the scanned string,
351and I<*flags> gives output flags.
352
353If the value is <= UV_MAX it is returned as a UV, the output flags are clear,
354and nothing is written to I<*result>. If the value is > UV_MAX C<grok_oct>
355returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags,
356and writes the value to I<*result> (or the value is discarded if I<result>
357is NULL).
358
359If C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the octal
360number may use '_' characters to separate digits.
53305cf1 361
362=cut
363 */
364
365UV
7fc63493 366Perl_grok_oct(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result) {
53305cf1 367 const char *s = start;
368 STRLEN len = *len_p;
369 UV value = 0;
370 NV value_nv = 0;
371
372 const UV max_div_8 = UV_MAX / 8;
585ec06d 373 const bool allow_underscores = (bool)(*flags & PERL_SCAN_ALLOW_UNDERSCORES);
53305cf1 374 bool overflowed = FALSE;
375
376 for (; len-- && *s; s++) {
377 /* gcc 2.95 optimiser not smart enough to figure that this subtraction
378 out front allows slicker code. */
379 int digit = *s - '0';
380 if (digit >= 0 && digit <= 7) {
381 /* Write it in this wonky order with a goto to attempt to get the
382 compiler to make the common case integer-only loop pretty tight.
383 */
384 redo:
385 if (!overflowed) {
386 if (value <= max_div_8) {
387 value = (value << 3) | digit;
388 continue;
389 }
390 /* Bah. We're just overflowed. */
391 if (ckWARN_d(WARN_OVERFLOW))
9014280d 392 Perl_warner(aTHX_ packWARN(WARN_OVERFLOW),
53305cf1 393 "Integer overflow in octal number");
394 overflowed = TRUE;
395 value_nv = (NV) value;
396 }
397 value_nv *= 8.0;
98994639 398 /* If an NV has not enough bits in its mantissa to
d1be9408 399 * represent a UV this summing of small low-order numbers
98994639 400 * is a waste of time (because the NV cannot preserve
401 * the low-order bits anyway): we could just remember when
53305cf1 402 * did we overflow and in the end just multiply value_nv by the
403 * right amount of 8-tuples. */
404 value_nv += (NV)digit;
405 continue;
406 }
407 if (digit == ('_' - '0') && len && allow_underscores
408 && (digit = s[1] - '0') && (digit >= 0 && digit <= 7))
409 {
410 --len;
411 ++s;
412 goto redo;
413 }
414 /* Allow \octal to work the DWIM way (that is, stop scanning
7b667b5f 415 * as soon as non-octal characters are seen, complain only if
53305cf1 416 * someone seems to want to use the digits eight and nine). */
417 if (digit == 8 || digit == 9) {
94dd8549 418 if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT) && ckWARN(WARN_DIGIT))
9014280d 419 Perl_warner(aTHX_ packWARN(WARN_DIGIT),
53305cf1 420 "Illegal octal digit '%c' ignored", *s);
421 }
422 break;
98994639 423 }
53305cf1 424
425 if ( ( overflowed && value_nv > 4294967295.0)
98994639 426#if UVSIZE > 4
53305cf1 427 || (!overflowed && value > 0xffffffff )
98994639 428#endif
429 ) {
430 if (ckWARN(WARN_PORTABLE))
9014280d 431 Perl_warner(aTHX_ packWARN(WARN_PORTABLE),
53305cf1 432 "Octal number > 037777777777 non-portable");
433 }
434 *len_p = s - start;
435 if (!overflowed) {
436 *flags = 0;
437 return value;
98994639 438 }
53305cf1 439 *flags = PERL_SCAN_GREATER_THAN_UV_MAX;
440 if (result)
441 *result = value_nv;
442 return UV_MAX;
443}
444
445/*
446=for apidoc scan_bin
447
448For backwards compatibility. Use C<grok_bin> instead.
449
450=for apidoc scan_hex
451
452For backwards compatibility. Use C<grok_hex> instead.
453
454=for apidoc scan_oct
455
456For backwards compatibility. Use C<grok_oct> instead.
457
458=cut
459 */
460
461NV
73d840c0 462Perl_scan_bin(pTHX_ const char *start, STRLEN len, STRLEN *retlen)
53305cf1 463{
464 NV rnv;
465 I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0;
73d840c0 466 const UV ruv = grok_bin (start, &len, &flags, &rnv);
53305cf1 467
468 *retlen = len;
469 return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv;
470}
471
472NV
73d840c0 473Perl_scan_oct(pTHX_ const char *start, STRLEN len, STRLEN *retlen)
53305cf1 474{
475 NV rnv;
476 I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0;
73d840c0 477 const UV ruv = grok_oct (start, &len, &flags, &rnv);
53305cf1 478
479 *retlen = len;
480 return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv;
481}
482
483NV
73d840c0 484Perl_scan_hex(pTHX_ const char *start, STRLEN len, STRLEN *retlen)
53305cf1 485{
486 NV rnv;
487 I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0;
73d840c0 488 const UV ruv = grok_hex (start, &len, &flags, &rnv);
53305cf1 489
490 *retlen = len;
491 return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv;
98994639 492}
493
494/*
495=for apidoc grok_numeric_radix
496
497Scan and skip for a numeric decimal separator (radix).
498
499=cut
500 */
501bool
502Perl_grok_numeric_radix(pTHX_ const char **sp, const char *send)
503{
504#ifdef USE_LOCALE_NUMERIC
97aff369 505 dVAR;
98994639 506 if (PL_numeric_radix_sv && IN_LOCALE) {
507 STRLEN len;
c4420975 508 const char * const radix = SvPV(PL_numeric_radix_sv, len);
98994639 509 if (*sp + len <= send && memEQ(*sp, radix, len)) {
510 *sp += len;
511 return TRUE;
512 }
513 }
514 /* always try "." if numeric radix didn't match because
515 * we may have data from different locales mixed */
516#endif
517 if (*sp < send && **sp == '.') {
518 ++*sp;
519 return TRUE;
520 }
521 return FALSE;
522}
523
524/*
525=for apidoc grok_number
526
527Recognise (or not) a number. The type of the number is returned
528(0 if unrecognised), otherwise it is a bit-ORed combination of
529IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX, IS_NUMBER_NOT_INT,
aa8b85de 530IS_NUMBER_NEG, IS_NUMBER_INFINITY, IS_NUMBER_NAN (defined in perl.h).
60939fb8 531
532If the value of the number can fit an in UV, it is returned in the *valuep
533IS_NUMBER_IN_UV will be set to indicate that *valuep is valid, IS_NUMBER_IN_UV
534will never be set unless *valuep is valid, but *valuep may have been assigned
535to during processing even though IS_NUMBER_IN_UV is not set on return.
536If valuep is NULL, IS_NUMBER_IN_UV will be set for the same cases as when
537valuep is non-NULL, but no actual assignment (or SEGV) will occur.
538
539IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were
540seen (in which case *valuep gives the true value truncated to an integer), and
541IS_NUMBER_NEG if the number is negative (in which case *valuep holds the
542absolute value). IS_NUMBER_IN_UV is not set if e notation was used or the
543number is larger than a UV.
98994639 544
545=cut
546 */
547int
548Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep)
549{
60939fb8 550 const char *s = pv;
c4420975 551 const char * const send = pv + len;
60939fb8 552 const UV max_div_10 = UV_MAX / 10;
553 const char max_mod_10 = UV_MAX % 10;
554 int numtype = 0;
555 int sawinf = 0;
aa8b85de 556 int sawnan = 0;
60939fb8 557
558 while (s < send && isSPACE(*s))
559 s++;
560 if (s == send) {
561 return 0;
562 } else if (*s == '-') {
563 s++;
564 numtype = IS_NUMBER_NEG;
565 }
566 else if (*s == '+')
567 s++;
568
569 if (s == send)
570 return 0;
571
572 /* next must be digit or the radix separator or beginning of infinity */
573 if (isDIGIT(*s)) {
574 /* UVs are at least 32 bits, so the first 9 decimal digits cannot
575 overflow. */
576 UV value = *s - '0';
577 /* This construction seems to be more optimiser friendly.
578 (without it gcc does the isDIGIT test and the *s - '0' separately)
579 With it gcc on arm is managing 6 instructions (6 cycles) per digit.
580 In theory the optimiser could deduce how far to unroll the loop
581 before checking for overflow. */
58bb9ec3 582 if (++s < send) {
583 int digit = *s - '0';
60939fb8 584 if (digit >= 0 && digit <= 9) {
585 value = value * 10 + digit;
58bb9ec3 586 if (++s < send) {
587 digit = *s - '0';
60939fb8 588 if (digit >= 0 && digit <= 9) {
589 value = value * 10 + digit;
58bb9ec3 590 if (++s < send) {
591 digit = *s - '0';
60939fb8 592 if (digit >= 0 && digit <= 9) {
593 value = value * 10 + digit;
58bb9ec3 594 if (++s < send) {
595 digit = *s - '0';
60939fb8 596 if (digit >= 0 && digit <= 9) {
597 value = value * 10 + digit;
58bb9ec3 598 if (++s < send) {
599 digit = *s - '0';
60939fb8 600 if (digit >= 0 && digit <= 9) {
601 value = value * 10 + digit;
58bb9ec3 602 if (++s < send) {
603 digit = *s - '0';
60939fb8 604 if (digit >= 0 && digit <= 9) {
605 value = value * 10 + digit;
58bb9ec3 606 if (++s < send) {
607 digit = *s - '0';
60939fb8 608 if (digit >= 0 && digit <= 9) {
609 value = value * 10 + digit;
58bb9ec3 610 if (++s < send) {
611 digit = *s - '0';
60939fb8 612 if (digit >= 0 && digit <= 9) {
613 value = value * 10 + digit;
58bb9ec3 614 if (++s < send) {
60939fb8 615 /* Now got 9 digits, so need to check
616 each time for overflow. */
58bb9ec3 617 digit = *s - '0';
60939fb8 618 while (digit >= 0 && digit <= 9
619 && (value < max_div_10
620 || (value == max_div_10
621 && digit <= max_mod_10))) {
622 value = value * 10 + digit;
58bb9ec3 623 if (++s < send)
624 digit = *s - '0';
60939fb8 625 else
626 break;
627 }
628 if (digit >= 0 && digit <= 9
51bd16da 629 && (s < send)) {
60939fb8 630 /* value overflowed.
631 skip the remaining digits, don't
632 worry about setting *valuep. */
633 do {
634 s++;
635 } while (s < send && isDIGIT(*s));
636 numtype |=
637 IS_NUMBER_GREATER_THAN_UV_MAX;
638 goto skip_value;
639 }
640 }
641 }
98994639 642 }
60939fb8 643 }
644 }
645 }
646 }
647 }
648 }
649 }
650 }
651 }
652 }
653 }
98994639 654 }
60939fb8 655 }
98994639 656 }
60939fb8 657 numtype |= IS_NUMBER_IN_UV;
658 if (valuep)
659 *valuep = value;
660
661 skip_value:
662 if (GROK_NUMERIC_RADIX(&s, send)) {
663 numtype |= IS_NUMBER_NOT_INT;
664 while (s < send && isDIGIT(*s)) /* optional digits after the radix */
665 s++;
98994639 666 }
60939fb8 667 }
668 else if (GROK_NUMERIC_RADIX(&s, send)) {
669 numtype |= IS_NUMBER_NOT_INT | IS_NUMBER_IN_UV; /* valuep assigned below */
670 /* no digits before the radix means we need digits after it */
671 if (s < send && isDIGIT(*s)) {
672 do {
673 s++;
674 } while (s < send && isDIGIT(*s));
675 if (valuep) {
676 /* integer approximation is valid - it's 0. */
677 *valuep = 0;
678 }
98994639 679 }
60939fb8 680 else
681 return 0;
682 } else if (*s == 'I' || *s == 'i') {
683 s++; if (s == send || (*s != 'N' && *s != 'n')) return 0;
684 s++; if (s == send || (*s != 'F' && *s != 'f')) return 0;
685 s++; if (s < send && (*s == 'I' || *s == 'i')) {
686 s++; if (s == send || (*s != 'N' && *s != 'n')) return 0;
687 s++; if (s == send || (*s != 'I' && *s != 'i')) return 0;
688 s++; if (s == send || (*s != 'T' && *s != 't')) return 0;
689 s++; if (s == send || (*s != 'Y' && *s != 'y')) return 0;
690 s++;
98994639 691 }
60939fb8 692 sawinf = 1;
aa8b85de 693 } else if (*s == 'N' || *s == 'n') {
694 /* XXX TODO: There are signaling NaNs and quiet NaNs. */
695 s++; if (s == send || (*s != 'A' && *s != 'a')) return 0;
696 s++; if (s == send || (*s != 'N' && *s != 'n')) return 0;
697 s++;
698 sawnan = 1;
699 } else
98994639 700 return 0;
60939fb8 701
702 if (sawinf) {
703 numtype &= IS_NUMBER_NEG; /* Keep track of sign */
704 numtype |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT;
aa8b85de 705 } else if (sawnan) {
706 numtype &= IS_NUMBER_NEG; /* Keep track of sign */
707 numtype |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT;
60939fb8 708 } else if (s < send) {
709 /* we can have an optional exponent part */
710 if (*s == 'e' || *s == 'E') {
711 /* The only flag we keep is sign. Blow away any "it's UV" */
712 numtype &= IS_NUMBER_NEG;
713 numtype |= IS_NUMBER_NOT_INT;
714 s++;
715 if (s < send && (*s == '-' || *s == '+'))
716 s++;
717 if (s < send && isDIGIT(*s)) {
718 do {
719 s++;
720 } while (s < send && isDIGIT(*s));
721 }
722 else
723 return 0;
724 }
725 }
726 while (s < send && isSPACE(*s))
727 s++;
728 if (s >= send)
aa8b85de 729 return numtype;
60939fb8 730 if (len == 10 && memEQ(pv, "0 but true", 10)) {
731 if (valuep)
732 *valuep = 0;
733 return IS_NUMBER_IN_UV;
734 }
735 return 0;
98994639 736}
737
4801ca72 738STATIC NV
98994639 739S_mulexp10(NV value, I32 exponent)
740{
741 NV result = 1.0;
742 NV power = 10.0;
743 bool negative = 0;
744 I32 bit;
745
746 if (exponent == 0)
747 return value;
20f6aaab 748 if (value == 0)
66a1b24b 749 return (NV)0;
87032ba1 750
24866caa 751 /* On OpenVMS VAX we by default use the D_FLOAT double format,
67597c89 752 * and that format does not have *easy* capabilities [1] for
24866caa 753 * overflowing doubles 'silently' as IEEE fp does. We also need
754 * to support G_FLOAT on both VAX and Alpha, and though the exponent
755 * range is much larger than D_FLOAT it still doesn't do silent
756 * overflow. Therefore we need to detect early whether we would
757 * overflow (this is the behaviour of the native string-to-float
758 * conversion routines, and therefore of native applications, too).
67597c89 759 *
24866caa 760 * [1] Trying to establish a condition handler to trap floating point
761 * exceptions is not a good idea. */
87032ba1 762
763 /* In UNICOS and in certain Cray models (such as T90) there is no
764 * IEEE fp, and no way at all from C to catch fp overflows gracefully.
765 * There is something you can do if you are willing to use some
766 * inline assembler: the instruction is called DFI-- but that will
767 * disable *all* floating point interrupts, a little bit too large
768 * a hammer. Therefore we need to catch potential overflows before
769 * it's too late. */
353813d9 770
771#if ((defined(VMS) && !defined(__IEEE_FP)) || defined(_UNICOS)) && defined(NV_MAX_10_EXP)
772 STMT_START {
c4420975 773 const NV exp_v = log10(value);
353813d9 774 if (exponent >= NV_MAX_10_EXP || exponent + exp_v >= NV_MAX_10_EXP)
775 return NV_MAX;
776 if (exponent < 0) {
777 if (-(exponent + exp_v) >= NV_MAX_10_EXP)
778 return 0.0;
779 while (-exponent >= NV_MAX_10_EXP) {
780 /* combination does not overflow, but 10^(-exponent) does */
781 value /= 10;
782 ++exponent;
783 }
784 }
785 } STMT_END;
87032ba1 786#endif
787
353813d9 788 if (exponent < 0) {
789 negative = 1;
790 exponent = -exponent;
791 }
98994639 792 for (bit = 1; exponent; bit <<= 1) {
793 if (exponent & bit) {
794 exponent ^= bit;
795 result *= power;
236f0012 796 /* Floating point exceptions are supposed to be turned off,
797 * but if we're obviously done, don't risk another iteration.
798 */
799 if (exponent == 0) break;
98994639 800 }
801 power *= power;
802 }
803 return negative ? value / result : value * result;
804}
805
806NV
807Perl_my_atof(pTHX_ const char* s)
808{
809 NV x = 0.0;
810#ifdef USE_LOCALE_NUMERIC
97aff369 811 dVAR;
98994639 812 if (PL_numeric_local && IN_LOCALE) {
813 NV y;
814
815 /* Scan the number twice; once using locale and once without;
816 * choose the larger result (in absolute value). */
a36244b7 817 Perl_atof2(s, x);
98994639 818 SET_NUMERIC_STANDARD();
a36244b7 819 Perl_atof2(s, y);
98994639 820 SET_NUMERIC_LOCAL();
821 if ((y < 0.0 && y < x) || (y > 0.0 && y > x))
822 return y;
823 }
824 else
a36244b7 825 Perl_atof2(s, x);
98994639 826#else
a36244b7 827 Perl_atof2(s, x);
98994639 828#endif
829 return x;
830}
831
832char*
833Perl_my_atof2(pTHX_ const char* orig, NV* value)
834{
20f6aaab 835 NV result[3] = {0.0, 0.0, 0.0};
e1ec3a88 836 const char* s = orig;
a36244b7 837#ifdef USE_PERL_ATOF
20f6aaab 838 UV accumulator[2] = {0,0}; /* before/after dp */
a36244b7 839 bool negative = 0;
e1ec3a88 840 const char* send = s + strlen(orig) - 1;
8194bf88 841 bool seen_digit = 0;
20f6aaab 842 I32 exp_adjust[2] = {0,0};
843 I32 exp_acc[2] = {-1, -1};
844 /* the current exponent adjust for the accumulators */
98994639 845 I32 exponent = 0;
8194bf88 846 I32 seen_dp = 0;
20f6aaab 847 I32 digit = 0;
848 I32 old_digit = 0;
8194bf88 849 I32 sig_digits = 0; /* noof significant digits seen so far */
850
851/* There is no point in processing more significant digits
852 * than the NV can hold. Note that NV_DIG is a lower-bound value,
853 * while we need an upper-bound value. We add 2 to account for this;
854 * since it will have been conservative on both the first and last digit.
855 * For example a 32-bit mantissa with an exponent of 4 would have
856 * exact values in the set
857 * 4
858 * 8
859 * ..
860 * 17179869172
861 * 17179869176
862 * 17179869180
863 *
864 * where for the purposes of calculating NV_DIG we would have to discount
865 * both the first and last digit, since neither can hold all values from
866 * 0..9; but for calculating the value we must examine those two digits.
867 */
868#define MAX_SIG_DIGITS (NV_DIG+2)
869
870/* the max number we can accumulate in a UV, and still safely do 10*N+9 */
871#define MAX_ACCUMULATE ( (UV) ((UV_MAX - 9)/10))
98994639 872
96a05aee 873 /* leading whitespace */
874 while (isSPACE(*s))
875 ++s;
876
98994639 877 /* sign */
878 switch (*s) {
879 case '-':
880 negative = 1;
881 /* fall through */
882 case '+':
883 ++s;
884 }
885
2b54f59f 886 /* punt to strtod for NaN/Inf; if no support for it there, tough luck */
887
888#ifdef HAS_STRTOD
889 if (*s == 'n' || *s == 'N' || *s == 'i' || *s == 'I') {
c042ae3a 890 const char *p = negative ? s - 1 : s;
2b54f59f 891 char *endp;
892 NV rslt;
893 rslt = strtod(p, &endp);
894 if (endp != p) {
895 *value = rslt;
896 return (char *)endp;
897 }
898 }
899#endif
900
8194bf88 901 /* we accumulate digits into an integer; when this becomes too
902 * large, we add the total to NV and start again */
98994639 903
8194bf88 904 while (1) {
905 if (isDIGIT(*s)) {
906 seen_digit = 1;
20f6aaab 907 old_digit = digit;
8194bf88 908 digit = *s++ - '0';
20f6aaab 909 if (seen_dp)
910 exp_adjust[1]++;
98994639 911
8194bf88 912 /* don't start counting until we see the first significant
913 * digit, eg the 5 in 0.00005... */
914 if (!sig_digits && digit == 0)
915 continue;
916
917 if (++sig_digits > MAX_SIG_DIGITS) {
98994639 918 /* limits of precision reached */
20f6aaab 919 if (digit > 5) {
920 ++accumulator[seen_dp];
921 } else if (digit == 5) {
922 if (old_digit % 2) { /* round to even - Allen */
923 ++accumulator[seen_dp];
924 }
925 }
926 if (seen_dp) {
927 exp_adjust[1]--;
928 } else {
929 exp_adjust[0]++;
930 }
8194bf88 931 /* skip remaining digits */
98994639 932 while (isDIGIT(*s)) {
98994639 933 ++s;
20f6aaab 934 if (! seen_dp) {
935 exp_adjust[0]++;
936 }
98994639 937 }
938 /* warn of loss of precision? */
98994639 939 }
8194bf88 940 else {
20f6aaab 941 if (accumulator[seen_dp] > MAX_ACCUMULATE) {
8194bf88 942 /* add accumulator to result and start again */
20f6aaab 943 result[seen_dp] = S_mulexp10(result[seen_dp],
944 exp_acc[seen_dp])
945 + (NV)accumulator[seen_dp];
946 accumulator[seen_dp] = 0;
947 exp_acc[seen_dp] = 0;
98994639 948 }
20f6aaab 949 accumulator[seen_dp] = accumulator[seen_dp] * 10 + digit;
950 ++exp_acc[seen_dp];
98994639 951 }
8194bf88 952 }
e1ec3a88 953 else if (!seen_dp && GROK_NUMERIC_RADIX(&s, send)) {
8194bf88 954 seen_dp = 1;
20f6aaab 955 if (sig_digits > MAX_SIG_DIGITS) {
956 ++s;
957 while (isDIGIT(*s)) {
958 ++s;
959 }
960 break;
961 }
8194bf88 962 }
963 else {
964 break;
98994639 965 }
966 }
967
20f6aaab 968 result[0] = S_mulexp10(result[0], exp_acc[0]) + (NV)accumulator[0];
969 if (seen_dp) {
970 result[1] = S_mulexp10(result[1], exp_acc[1]) + (NV)accumulator[1];
971 }
98994639 972
8194bf88 973 if (seen_digit && (*s == 'e' || *s == 'E')) {
98994639 974 bool expnegative = 0;
975
976 ++s;
977 switch (*s) {
978 case '-':
979 expnegative = 1;
980 /* fall through */
981 case '+':
982 ++s;
983 }
984 while (isDIGIT(*s))
985 exponent = exponent * 10 + (*s++ - '0');
986 if (expnegative)
987 exponent = -exponent;
988 }
989
20f6aaab 990
991
98994639 992 /* now apply the exponent */
20f6aaab 993
994 if (seen_dp) {
995 result[2] = S_mulexp10(result[0],exponent+exp_adjust[0])
996 + S_mulexp10(result[1],exponent-exp_adjust[1]);
997 } else {
998 result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]);
999 }
98994639 1000
1001 /* now apply the sign */
1002 if (negative)
20f6aaab 1003 result[2] = -result[2];
a36244b7 1004#endif /* USE_PERL_ATOF */
20f6aaab 1005 *value = result[2];
73d840c0 1006 return (char *)s;
98994639 1007}
1008
55954f19 1009#if ! defined(HAS_MODFL) && defined(HAS_AINTL) && defined(HAS_COPYSIGNL)
1010long double
1011Perl_my_modfl(long double x, long double *ip)
1012{
1013 *ip = aintl(x);
1014 return (x == *ip ? copysignl(0.0L, x) : x - *ip);
1015}
1016#endif
1017
1018#if ! defined(HAS_FREXPL) && defined(HAS_ILOGBL) && defined(HAS_SCALBNL)
1019long double
1020Perl_my_frexpl(long double x, int *e) {
1021 *e = x == 0.0L ? 0 : ilogbl(x) + 1;
1022 return (scalbnl(x, -*e));
1023}
1024#endif
66610fdd 1025
1026/*
1027 * Local variables:
1028 * c-indentation-style: bsd
1029 * c-basic-offset: 4
1030 * indent-tabs-mode: t
1031 * End:
1032 *
37442d52 1033 * ex: set ts=8 sts=4 sw=4 noet:
1034 */