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98994639
HS
1/* numeric.c
2 *
663f364b 3 * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
1129b882 4 * 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
98994639
HS
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/*
4ac71550
TC
12 * "That only makes eleven (plus one mislaid) and not fourteen,
13 * unless wizards count differently to other people." --Beorn
14 *
15 * [p.115 of _The Hobbit_: "Queer Lodgings"]
98994639
HS
16 */
17
ccfc67b7
JH
18/*
19=head1 Numeric functions
166f8a29 20
7fefc6c1
KW
21=cut
22
166f8a29
DM
23This file contains all the stuff needed by perl for manipulating numeric
24values, including such things as replacements for the OS's atof() function
25
ccfc67b7
JH
26*/
27
98994639
HS
28#include "EXTERN.h"
29#define PERL_IN_NUMERIC_C
30#include "perl.h"
31
32U32
ddeaf645 33Perl_cast_ulong(NV f)
98994639
HS
34{
35 if (f < 0.0)
36 return f < I32_MIN ? (U32) I32_MIN : (U32)(I32) f;
37 if (f < U32_MAX_P1) {
38#if CASTFLAGS & 2
39 if (f < U32_MAX_P1_HALF)
40 return (U32) f;
41 f -= U32_MAX_P1_HALF;
42 return ((U32) f) | (1 + U32_MAX >> 1);
43#else
44 return (U32) f;
45#endif
46 }
47 return f > 0 ? U32_MAX : 0 /* NaN */;
48}
49
50I32
ddeaf645 51Perl_cast_i32(NV f)
98994639
HS
52{
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
ddeaf645 69Perl_cast_iv(NV f)
98994639
HS
70{
71 if (f < IV_MAX_P1)
72 return f < IV_MIN ? IV_MIN : (IV) f;
73 if (f < UV_MAX_P1) {
74#if CASTFLAGS & 2
75 /* For future flexibility allowing for sizeof(UV) >= sizeof(IV) */
76 if (f < UV_MAX_P1_HALF)
77 return (IV)(UV) f;
78 f -= UV_MAX_P1_HALF;
79 return (IV)(((UV) f) | (1 + UV_MAX >> 1));
80#else
81 return (IV)(UV) f;
82#endif
83 }
84 return f > 0 ? (IV)UV_MAX : 0 /* NaN */;
85}
86
87UV
ddeaf645 88Perl_cast_uv(NV f)
98994639
HS
89{
90 if (f < 0.0)
91 return f < IV_MIN ? (UV) IV_MIN : (UV)(IV) f;
92 if (f < UV_MAX_P1) {
93#if CASTFLAGS & 2
94 if (f < UV_MAX_P1_HALF)
95 return (UV) f;
96 f -= UV_MAX_P1_HALF;
97 return ((UV) f) | (1 + UV_MAX >> 1);
98#else
99 return (UV) f;
100#endif
101 }
102 return f > 0 ? UV_MAX : 0 /* NaN */;
103}
104
53305cf1
NC
105/*
106=for apidoc grok_bin
98994639 107
53305cf1
NC
108converts a string representing a binary number to numeric form.
109
110On entry I<start> and I<*len> give the string to scan, I<*flags> gives
111conversion flags, and I<result> should be NULL or a pointer to an NV.
112The scan stops at the end of the string, or the first invalid character.
7b667b5f
MHM
113Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an
114invalid character will also trigger a warning.
115On return I<*len> is set to the length of the scanned string,
116and I<*flags> gives output flags.
53305cf1 117
7fc63493 118If the value is <= C<UV_MAX> it is returned as a UV, the output flags are clear,
72d33970 119and nothing is written to I<*result>. If the value is > UV_MAX C<grok_bin>
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NC
120returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags,
121and writes the value to I<*result> (or the value is discarded if I<result>
122is NULL).
123
7b667b5f 124The binary number may optionally be prefixed with "0b" or "b" unless
72d33970 125C<PERL_SCAN_DISALLOW_PREFIX> is set in I<*flags> on entry. If
a4c04bdc 126C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the binary
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NC
127number may use '_' characters to separate digits.
128
129=cut
02470786
KW
130
131Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE
132which suppresses any message for non-portable numbers that are still valid
133on this platform.
53305cf1
NC
134 */
135
136UV
7918f24d
NC
137Perl_grok_bin(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result)
138{
53305cf1
NC
139 const char *s = start;
140 STRLEN len = *len_p;
141 UV value = 0;
142 NV value_nv = 0;
143
144 const UV max_div_2 = UV_MAX / 2;
f2338a2e 145 const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES);
53305cf1 146 bool overflowed = FALSE;
7fc63493 147 char bit;
53305cf1 148
7918f24d
NC
149 PERL_ARGS_ASSERT_GROK_BIN;
150
a4c04bdc
NC
151 if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) {
152 /* strip off leading b or 0b.
153 for compatibility silently suffer "b" and "0b" as valid binary
154 numbers. */
155 if (len >= 1) {
305b8651 156 if (isALPHA_FOLD_EQ(s[0], 'b')) {
a4c04bdc
NC
157 s++;
158 len--;
159 }
305b8651 160 else if (len >= 2 && s[0] == '0' && (isALPHA_FOLD_EQ(s[1], 'b'))) {
a4c04bdc
NC
161 s+=2;
162 len-=2;
163 }
164 }
53305cf1
NC
165 }
166
7fc63493 167 for (; len-- && (bit = *s); s++) {
53305cf1
NC
168 if (bit == '0' || bit == '1') {
169 /* Write it in this wonky order with a goto to attempt to get the
170 compiler to make the common case integer-only loop pretty tight.
171 With gcc seems to be much straighter code than old scan_bin. */
172 redo:
173 if (!overflowed) {
174 if (value <= max_div_2) {
175 value = (value << 1) | (bit - '0');
176 continue;
177 }
178 /* Bah. We're just overflowed. */
dcbac5bb 179 /* diag_listed_as: Integer overflow in %s number */
9b387841
NC
180 Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW),
181 "Integer overflow in binary number");
53305cf1
NC
182 overflowed = TRUE;
183 value_nv = (NV) value;
184 }
185 value_nv *= 2.0;
98994639 186 /* If an NV has not enough bits in its mantissa to
d1be9408 187 * represent a UV this summing of small low-order numbers
98994639
HS
188 * is a waste of time (because the NV cannot preserve
189 * the low-order bits anyway): we could just remember when
53305cf1 190 * did we overflow and in the end just multiply value_nv by the
98994639 191 * right amount. */
53305cf1
NC
192 value_nv += (NV)(bit - '0');
193 continue;
194 }
195 if (bit == '_' && len && allow_underscores && (bit = s[1])
196 && (bit == '0' || bit == '1'))
98994639
HS
197 {
198 --len;
199 ++s;
53305cf1 200 goto redo;
98994639 201 }
a2a5de95
NC
202 if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT))
203 Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT),
204 "Illegal binary digit '%c' ignored", *s);
53305cf1 205 break;
98994639 206 }
53305cf1
NC
207
208 if ( ( overflowed && value_nv > 4294967295.0)
98994639 209#if UVSIZE > 4
02470786
KW
210 || (!overflowed && value > 0xffffffff
211 && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE))
98994639
HS
212#endif
213 ) {
a2a5de95
NC
214 Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE),
215 "Binary number > 0b11111111111111111111111111111111 non-portable");
53305cf1
NC
216 }
217 *len_p = s - start;
218 if (!overflowed) {
219 *flags = 0;
220 return value;
98994639 221 }
53305cf1
NC
222 *flags = PERL_SCAN_GREATER_THAN_UV_MAX;
223 if (result)
224 *result = value_nv;
225 return UV_MAX;
98994639
HS
226}
227
53305cf1
NC
228/*
229=for apidoc grok_hex
230
231converts a string representing a hex number to numeric form.
232
c2da02fc 233On entry I<start> and I<*len_p> give the string to scan, I<*flags> gives
53305cf1 234conversion flags, and I<result> should be NULL or a pointer to an NV.
7b667b5f
MHM
235The scan stops at the end of the string, or the first invalid character.
236Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an
237invalid character will also trigger a warning.
238On return I<*len> is set to the length of the scanned string,
239and I<*flags> gives output flags.
53305cf1
NC
240
241If the value is <= UV_MAX it is returned as a UV, the output flags are clear,
72d33970 242and nothing is written to I<*result>. If the value is > UV_MAX C<grok_hex>
53305cf1
NC
243returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags,
244and writes the value to I<*result> (or the value is discarded if I<result>
245is NULL).
246
d1be9408 247The hex number may optionally be prefixed with "0x" or "x" unless
72d33970 248C<PERL_SCAN_DISALLOW_PREFIX> is set in I<*flags> on entry. If
a4c04bdc 249C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the hex
53305cf1
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250number may use '_' characters to separate digits.
251
252=cut
02470786
KW
253
254Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE
baf48926 255which suppresses any message for non-portable numbers, but which are valid
02470786 256on this platform.
53305cf1
NC
257 */
258
259UV
7918f24d
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260Perl_grok_hex(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result)
261{
53305cf1
NC
262 const char *s = start;
263 STRLEN len = *len_p;
264 UV value = 0;
265 NV value_nv = 0;
53305cf1 266 const UV max_div_16 = UV_MAX / 16;
f2338a2e 267 const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES);
53305cf1 268 bool overflowed = FALSE;
98994639 269
7918f24d
NC
270 PERL_ARGS_ASSERT_GROK_HEX;
271
a4c04bdc
NC
272 if (!(*flags & PERL_SCAN_DISALLOW_PREFIX)) {
273 /* strip off leading x or 0x.
274 for compatibility silently suffer "x" and "0x" as valid hex numbers.
275 */
276 if (len >= 1) {
305b8651 277 if (isALPHA_FOLD_EQ(s[0], 'x')) {
a4c04bdc
NC
278 s++;
279 len--;
280 }
305b8651 281 else if (len >= 2 && s[0] == '0' && (isALPHA_FOLD_EQ(s[1], 'x'))) {
a4c04bdc
NC
282 s+=2;
283 len-=2;
284 }
285 }
98994639
HS
286 }
287
288 for (; len-- && *s; s++) {
626ef089 289 if (isXDIGIT(*s)) {
53305cf1
NC
290 /* Write it in this wonky order with a goto to attempt to get the
291 compiler to make the common case integer-only loop pretty tight.
292 With gcc seems to be much straighter code than old scan_hex. */
293 redo:
294 if (!overflowed) {
295 if (value <= max_div_16) {
626ef089 296 value = (value << 4) | XDIGIT_VALUE(*s);
53305cf1
NC
297 continue;
298 }
299 /* Bah. We're just overflowed. */
dcbac5bb 300 /* diag_listed_as: Integer overflow in %s number */
9b387841
NC
301 Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW),
302 "Integer overflow in hexadecimal number");
53305cf1
NC
303 overflowed = TRUE;
304 value_nv = (NV) value;
305 }
306 value_nv *= 16.0;
307 /* If an NV has not enough bits in its mantissa to
d1be9408 308 * represent a UV this summing of small low-order numbers
53305cf1
NC
309 * is a waste of time (because the NV cannot preserve
310 * the low-order bits anyway): we could just remember when
311 * did we overflow and in the end just multiply value_nv by the
312 * right amount of 16-tuples. */
626ef089 313 value_nv += (NV) XDIGIT_VALUE(*s);
53305cf1
NC
314 continue;
315 }
316 if (*s == '_' && len && allow_underscores && s[1]
626ef089 317 && isXDIGIT(s[1]))
98994639
HS
318 {
319 --len;
320 ++s;
53305cf1 321 goto redo;
98994639 322 }
a2a5de95
NC
323 if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT))
324 Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT),
53305cf1
NC
325 "Illegal hexadecimal digit '%c' ignored", *s);
326 break;
327 }
328
329 if ( ( overflowed && value_nv > 4294967295.0)
330#if UVSIZE > 4
02470786
KW
331 || (!overflowed && value > 0xffffffff
332 && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE))
53305cf1
NC
333#endif
334 ) {
a2a5de95
NC
335 Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE),
336 "Hexadecimal number > 0xffffffff non-portable");
53305cf1
NC
337 }
338 *len_p = s - start;
339 if (!overflowed) {
340 *flags = 0;
341 return value;
342 }
343 *flags = PERL_SCAN_GREATER_THAN_UV_MAX;
344 if (result)
345 *result = value_nv;
346 return UV_MAX;
347}
348
349/*
350=for apidoc grok_oct
351
7b667b5f
MHM
352converts a string representing an octal number to numeric form.
353
354On entry I<start> and I<*len> give the string to scan, I<*flags> gives
355conversion flags, and I<result> should be NULL or a pointer to an NV.
356The scan stops at the end of the string, or the first invalid character.
357Unless C<PERL_SCAN_SILENT_ILLDIGIT> is set in I<*flags>, encountering an
154bd527 3588 or 9 will also trigger a warning.
7b667b5f
MHM
359On return I<*len> is set to the length of the scanned string,
360and I<*flags> gives output flags.
361
362If the value is <= UV_MAX it is returned as a UV, the output flags are clear,
72d33970 363and nothing is written to I<*result>. If the value is > UV_MAX C<grok_oct>
7b667b5f
MHM
364returns UV_MAX, sets C<PERL_SCAN_GREATER_THAN_UV_MAX> in the output flags,
365and writes the value to I<*result> (or the value is discarded if I<result>
366is NULL).
367
368If C<PERL_SCAN_ALLOW_UNDERSCORES> is set in I<*flags> then the octal
369number may use '_' characters to separate digits.
53305cf1
NC
370
371=cut
02470786 372
333ae27c
KW
373Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE>
374which suppresses any message for non-portable numbers, but which are valid
02470786 375on this platform.
53305cf1
NC
376 */
377
378UV
7918f24d
NC
379Perl_grok_oct(pTHX_ const char *start, STRLEN *len_p, I32 *flags, NV *result)
380{
53305cf1
NC
381 const char *s = start;
382 STRLEN len = *len_p;
383 UV value = 0;
384 NV value_nv = 0;
53305cf1 385 const UV max_div_8 = UV_MAX / 8;
f2338a2e 386 const bool allow_underscores = cBOOL(*flags & PERL_SCAN_ALLOW_UNDERSCORES);
53305cf1
NC
387 bool overflowed = FALSE;
388
7918f24d
NC
389 PERL_ARGS_ASSERT_GROK_OCT;
390
53305cf1 391 for (; len-- && *s; s++) {
626ef089 392 if (isOCTAL(*s)) {
53305cf1
NC
393 /* Write it in this wonky order with a goto to attempt to get the
394 compiler to make the common case integer-only loop pretty tight.
395 */
396 redo:
397 if (!overflowed) {
398 if (value <= max_div_8) {
626ef089 399 value = (value << 3) | OCTAL_VALUE(*s);
53305cf1
NC
400 continue;
401 }
402 /* Bah. We're just overflowed. */
dcbac5bb 403 /* diag_listed_as: Integer overflow in %s number */
9b387841
NC
404 Perl_ck_warner_d(aTHX_ packWARN(WARN_OVERFLOW),
405 "Integer overflow in octal number");
53305cf1
NC
406 overflowed = TRUE;
407 value_nv = (NV) value;
408 }
409 value_nv *= 8.0;
98994639 410 /* If an NV has not enough bits in its mantissa to
d1be9408 411 * represent a UV this summing of small low-order numbers
98994639
HS
412 * is a waste of time (because the NV cannot preserve
413 * the low-order bits anyway): we could just remember when
53305cf1
NC
414 * did we overflow and in the end just multiply value_nv by the
415 * right amount of 8-tuples. */
626ef089 416 value_nv += (NV) OCTAL_VALUE(*s);
53305cf1
NC
417 continue;
418 }
626ef089
KW
419 if (*s == '_' && len && allow_underscores && isOCTAL(s[1])) {
420 --len;
421 ++s;
422 goto redo;
423 }
53305cf1 424 /* Allow \octal to work the DWIM way (that is, stop scanning
7b667b5f 425 * as soon as non-octal characters are seen, complain only if
626ef089
KW
426 * someone seems to want to use the digits eight and nine. Since we
427 * know it is not octal, then if isDIGIT, must be an 8 or 9). */
428 if (isDIGIT(*s)) {
a2a5de95
NC
429 if (!(*flags & PERL_SCAN_SILENT_ILLDIGIT))
430 Perl_ck_warner(aTHX_ packWARN(WARN_DIGIT),
431 "Illegal octal digit '%c' ignored", *s);
53305cf1
NC
432 }
433 break;
98994639 434 }
53305cf1
NC
435
436 if ( ( overflowed && value_nv > 4294967295.0)
98994639 437#if UVSIZE > 4
02470786
KW
438 || (!overflowed && value > 0xffffffff
439 && ! (*flags & PERL_SCAN_SILENT_NON_PORTABLE))
98994639
HS
440#endif
441 ) {
a2a5de95
NC
442 Perl_ck_warner(aTHX_ packWARN(WARN_PORTABLE),
443 "Octal number > 037777777777 non-portable");
53305cf1
NC
444 }
445 *len_p = s - start;
446 if (!overflowed) {
447 *flags = 0;
448 return value;
98994639 449 }
53305cf1
NC
450 *flags = PERL_SCAN_GREATER_THAN_UV_MAX;
451 if (result)
452 *result = value_nv;
453 return UV_MAX;
454}
455
456/*
457=for apidoc scan_bin
458
72d33970 459For backwards compatibility. Use C<grok_bin> instead.
53305cf1
NC
460
461=for apidoc scan_hex
462
72d33970 463For backwards compatibility. Use C<grok_hex> instead.
53305cf1
NC
464
465=for apidoc scan_oct
466
72d33970 467For backwards compatibility. Use C<grok_oct> instead.
53305cf1
NC
468
469=cut
470 */
471
472NV
73d840c0 473Perl_scan_bin(pTHX_ const char *start, STRLEN len, STRLEN *retlen)
53305cf1
NC
474{
475 NV rnv;
476 I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0;
73d840c0 477 const UV ruv = grok_bin (start, &len, &flags, &rnv);
53305cf1 478
7918f24d
NC
479 PERL_ARGS_ASSERT_SCAN_BIN;
480
53305cf1
NC
481 *retlen = len;
482 return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv;
483}
484
485NV
73d840c0 486Perl_scan_oct(pTHX_ const char *start, STRLEN len, STRLEN *retlen)
53305cf1
NC
487{
488 NV rnv;
489 I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0;
73d840c0 490 const UV ruv = grok_oct (start, &len, &flags, &rnv);
53305cf1 491
7918f24d
NC
492 PERL_ARGS_ASSERT_SCAN_OCT;
493
53305cf1
NC
494 *retlen = len;
495 return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv;
496}
497
498NV
73d840c0 499Perl_scan_hex(pTHX_ const char *start, STRLEN len, STRLEN *retlen)
53305cf1
NC
500{
501 NV rnv;
502 I32 flags = *retlen ? PERL_SCAN_ALLOW_UNDERSCORES : 0;
73d840c0 503 const UV ruv = grok_hex (start, &len, &flags, &rnv);
53305cf1 504
7918f24d
NC
505 PERL_ARGS_ASSERT_SCAN_HEX;
506
53305cf1
NC
507 *retlen = len;
508 return (flags & PERL_SCAN_GREATER_THAN_UV_MAX) ? rnv : (NV)ruv;
98994639
HS
509}
510
511/*
512=for apidoc grok_numeric_radix
513
514Scan and skip for a numeric decimal separator (radix).
515
516=cut
517 */
518bool
519Perl_grok_numeric_radix(pTHX_ const char **sp, const char *send)
520{
521#ifdef USE_LOCALE_NUMERIC
7918f24d
NC
522 PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX;
523
d6ded950 524 if (IN_LC(LC_NUMERIC)) {
67d796ae
KW
525 DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
526 STORE_LC_NUMERIC_SET_TO_NEEDED();
21431899 527 if (PL_numeric_radix_sv) {
c5a7e38e
KW
528 STRLEN len;
529 const char * const radix = SvPV(PL_numeric_radix_sv, len);
530 if (*sp + len <= send && memEQ(*sp, radix, len)) {
531 *sp += len;
532 RESTORE_LC_NUMERIC();
533 return TRUE;
534 }
21431899
KW
535 }
536 RESTORE_LC_NUMERIC();
98994639
HS
537 }
538 /* always try "." if numeric radix didn't match because
539 * we may have data from different locales mixed */
540#endif
7918f24d
NC
541
542 PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX;
543
98994639
HS
544 if (*sp < send && **sp == '.') {
545 ++*sp;
546 return TRUE;
547 }
548 return FALSE;
549}
550
569f27e5 551/*
ff4eb398
JH
552=for apidoc grok_infnan
553
554Helper for grok_number(), accepts various ways of spelling "infinity"
555or "not a number", and returns one of the following flag combinations:
556
557 IS_NUMBER_INFINITE
558 IS_NUMBER_NAN
559 IS_NUMBER_INFINITE | IS_NUMBER_NEG
560 IS_NUMBER_NAN | IS_NUMBER_NEG
561 0
562
62bdc035 563possibly |-ed with IS_NUMBER_TRAILING.
b489e20f 564
62bdc035
JH
565If an infinity or a not-a-number is recognized, the *sp will point to
566one byte past the end of the recognized string. If the recognition fails,
ff4eb398
JH
567zero is returned, and the *sp will not move.
568
569=cut
570*/
571
572int
3823048b 573Perl_grok_infnan(pTHX_ const char** sp, const char* send)
ff4eb398
JH
574{
575 const char* s = *sp;
576 int flags = 0;
62bdc035 577 bool odh = FALSE; /* one-dot-hash: 1.#INF */
ff4eb398
JH
578
579 PERL_ARGS_ASSERT_GROK_INFNAN;
580
8c12dc63
JH
581 if (*s == '+') {
582 s++; if (s == send) return 0;
583 }
584 else if (*s == '-') {
ff4eb398
JH
585 flags |= IS_NUMBER_NEG; /* Yes, -NaN happens. Incorrect but happens. */
586 s++; if (s == send) return 0;
587 }
588
589 if (*s == '1') {
62bdc035
JH
590 /* Visual C: 1.#SNAN, -1.#QNAN, 1#INF, 1.#IND (maybe also 1.#NAN)
591 * Let's keep the dot optional. */
ff4eb398
JH
592 s++; if (s == send) return 0;
593 if (*s == '.') {
594 s++; if (s == send) return 0;
595 }
596 if (*s == '#') {
597 s++; if (s == send) return 0;
598 } else
599 return 0;
e855f543 600 odh = TRUE;
ff4eb398
JH
601 }
602
305b8651 603 if (isALPHA_FOLD_EQ(*s, 'I')) {
62bdc035
JH
604 /* INF or IND (1.#IND is "indeterminate", a certain type of NAN) */
605
305b8651 606 s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0;
ff4eb398 607 s++; if (s == send) return 0;
305b8651 608 if (isALPHA_FOLD_EQ(*s, 'F')) {
ff4eb398 609 s++;
b8974fcb
JH
610 if (s < send && (isALPHA_FOLD_EQ(*s, 'I'))) {
611 int fail =
612 flags | IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT | IS_NUMBER_TRAILING;
613 s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return fail;
614 s++; if (s == send || isALPHA_FOLD_NE(*s, 'I')) return fail;
615 s++; if (s == send || isALPHA_FOLD_NE(*s, 'T')) return fail;
616 s++; if (s == send || isALPHA_FOLD_NE(*s, 'Y')) return fail;
3396ed30 617 s++;
b8974fcb
JH
618 } else if (odh) {
619 while (*s == '0') { /* 1.#INF00 */
620 s++;
621 }
3396ed30 622 }
b489e20f
JH
623 while (s < send && isSPACE(*s))
624 s++;
625 if (s < send && *s) {
3396ed30 626 flags |= IS_NUMBER_TRAILING;
fae4db12 627 }
ff4eb398
JH
628 flags |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT;
629 }
e855f543 630 else if (isALPHA_FOLD_EQ(*s, 'D') && odh) { /* 1.#IND */
ff4eb398
JH
631 s++;
632 flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT;
fae4db12
JH
633 while (*s == '0') { /* 1.#IND00 */
634 s++;
635 }
1e9aa12f
JH
636 if (*s) {
637 flags |= IS_NUMBER_TRAILING;
638 }
ff4eb398
JH
639 } else
640 return 0;
ff4eb398
JH
641 }
642 else {
62bdc035 643 /* Maybe NAN of some sort */
3823048b
JH
644
645 if (isALPHA_FOLD_EQ(*s, 'S') || isALPHA_FOLD_EQ(*s, 'Q')) {
646 /* snan, qNaN */
647 /* XXX do something with the snan/qnan difference */
648 s++; if (s == send) return 0;
649 }
650
651 if (isALPHA_FOLD_EQ(*s, 'N')) {
652 s++; if (s == send || isALPHA_FOLD_NE(*s, 'A')) return 0;
653 s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0;
654 s++;
655
656 flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT;
657
658 /* NaN can be followed by various stuff (NaNQ, NaNS), but
659 * there are also multiple different NaN values, and some
660 * implementations output the "payload" values,
661 * e.g. NaN123, NAN(abc), while some legacy implementations
662 * have weird stuff like NaN%. */
663 if (isALPHA_FOLD_EQ(*s, 'q') ||
664 isALPHA_FOLD_EQ(*s, 's')) {
665 /* "nanq" or "nans" are ok, though generating
666 * these portably is tricky. */
667 s++;
668 }
669 if (*s == '(') {
670 /* C99 style "nan(123)" or Perlish equivalent "nan($uv)". */
671 const char *t;
672 s++;
673 if (s == send) {
674 return flags | IS_NUMBER_TRAILING;
675 }
676 t = s + 1;
677 while (t < send && *t && *t != ')') {
678 t++;
679 }
680 if (t == send) {
681 return flags | IS_NUMBER_TRAILING;
682 }
683 if (*t == ')') {
684 int nantype;
685 UV nanval;
686 if (s[0] == '0' && s + 2 < t &&
687 isALPHA_FOLD_EQ(s[1], 'x') &&
688 isXDIGIT(s[2])) {
689 STRLEN len = t - s;
690 I32 flags = PERL_SCAN_ALLOW_UNDERSCORES;
691 nanval = grok_hex(s, &len, &flags, NULL);
692 if ((flags & PERL_SCAN_GREATER_THAN_UV_MAX)) {
693 nantype = 0;
694 } else {
695 nantype = IS_NUMBER_IN_UV;
696 }
697 s += len;
698 } else if (s[0] == '0' && s + 2 < t &&
699 isALPHA_FOLD_EQ(s[1], 'b') &&
700 (s[2] == '0' || s[2] == '1')) {
701 STRLEN len = t - s;
702 I32 flags = PERL_SCAN_ALLOW_UNDERSCORES;
703 nanval = grok_bin(s, &len, &flags, NULL);
704 if ((flags & PERL_SCAN_GREATER_THAN_UV_MAX)) {
705 nantype = 0;
706 } else {
707 nantype = IS_NUMBER_IN_UV;
708 }
709 s += len;
710 } else {
711 const char *u;
712 nantype =
713 grok_number_flags(s, t - s, &nanval,
714 PERL_SCAN_TRAILING |
715 PERL_SCAN_ALLOW_UNDERSCORES);
716 /* Unfortunately grok_number_flags() doesn't
717 * tell how far we got and the ')' will always
718 * be "trailing", so we need to double-check
719 * whether we had something dubious. */
720 for (u = s; u < t; u++) {
721 if (!isDIGIT(*u)) {
722 flags |= IS_NUMBER_TRAILING;
723 break;
724 }
725 }
726 s = u;
727 }
728
729 /* XXX Doesn't do octal: nan("0123").
730 * Probably not a big loss. */
731
732 if ((nantype & IS_NUMBER_NOT_INT) ||
733 !(nantype && IS_NUMBER_IN_UV)) {
734 /* XXX the nanval is currently unused, that is,
735 * not inserted as the NaN payload of the NV.
736 * But the above code already parses the C99
737 * nan(...) format. See below, and see also
738 * the nan() in POSIX.xs.
739 *
740 * Certain configuration combinations where
741 * NVSIZE is greater than UVSIZE mean that
742 * a single UV cannot contain all the possible
743 * NaN payload bits. There would need to be
744 * some more generic syntax than "nan($uv)".
745 *
746 * Issues to keep in mind:
747 *
748 * (1) In most common cases there would
749 * not be an integral number of bytes that
750 * could be set, only a certain number of bits.
751 * For example for the common case of
752 * NVSIZE == UVSIZE == 8 there is room for 52
753 * bits in the payload, but the most significant
754 * bit is commonly reserved for the
755 * signaling/quiet bit, leaving 51 bits.
756 * Furthermore, the C99 nan() is supposed
757 * to generate quiet NaNs, so it is doubtful
758 * whether it should be able to generate
759 * signaling NaNs. For the x86 80-bit doubles
760 * (if building a long double Perl) there would
761 * be 62 bits (s/q bit being the 63rd).
762 *
763 * (2) Endianness of the payload bits. If the
764 * payload is specified as an UV, the low-order
765 * bits of the UV are naturally little-endianed
766 * (rightmost) bits of the payload. The endianness
767 * of UVs and NVs can be different. */
768 return 0;
769 }
770 if (s < t) {
771 flags |= IS_NUMBER_TRAILING;
772 }
773 } else {
774 /* Looked like nan(...), but no close paren. */
775 flags |= IS_NUMBER_TRAILING;
776 }
777 } else {
778 while (s < send && isSPACE(*s))
779 s++;
780 if (s < send && *s) {
781 /* Note that we here implicitly accept (parse as
782 * "nan", but with warnings) also any other weird
783 * trailing stuff for "nan". In the above we just
784 * check that if we got the C99-style "nan(...)",
785 * the "..." looks sane.
786 * If in future we accept more ways of specifying
787 * the nan payload, the accepting would happen around
788 * here. */
789 flags |= IS_NUMBER_TRAILING;
790 }
791 }
792 s = send;
793 }
794 else
795 return 0;
ff4eb398
JH
796 }
797
b489e20f
JH
798 while (s < send && isSPACE(*s))
799 s++;
800
a1fe7cea
JH
801 *sp = s;
802 return flags;
ff4eb398
JH
803}
804
13393a5e 805/*
3823048b 806=for apidoc grok_number_flags
13393a5e
JH
807
808Recognise (or not) a number. The type of the number is returned
809(0 if unrecognised), otherwise it is a bit-ORed combination of
810IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX, IS_NUMBER_NOT_INT,
811IS_NUMBER_NEG, IS_NUMBER_INFINITY, IS_NUMBER_NAN (defined in perl.h).
812
813If the value of the number can fit in a UV, it is returned in the *valuep
814IS_NUMBER_IN_UV will be set to indicate that *valuep is valid, IS_NUMBER_IN_UV
815will never be set unless *valuep is valid, but *valuep may have been assigned
816to during processing even though IS_NUMBER_IN_UV is not set on return.
817If valuep is NULL, IS_NUMBER_IN_UV will be set for the same cases as when
818valuep is non-NULL, but no actual assignment (or SEGV) will occur.
819
820IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were
821seen (in which case *valuep gives the true value truncated to an integer), and
822IS_NUMBER_NEG if the number is negative (in which case *valuep holds the
823absolute value). IS_NUMBER_IN_UV is not set if e notation was used or the
824number is larger than a UV.
825
826C<flags> allows only C<PERL_SCAN_TRAILING>, which allows for trailing
827non-numeric text on an otherwise successful I<grok>, setting
828C<IS_NUMBER_TRAILING> on the result.
829
830=for apidoc grok_number
831
832Identical to grok_number_flags() with flags set to zero.
833
834=cut
835 */
836int
837Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep)
838{
839 PERL_ARGS_ASSERT_GROK_NUMBER;
840
841 return grok_number_flags(pv, len, valuep, 0);
842}
843
945b524a
JH
844static const UV uv_max_div_10 = UV_MAX / 10;
845static const U8 uv_max_mod_10 = UV_MAX % 10;
846
3f7602fa 847int
3823048b 848Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags)
3f7602fa 849{
60939fb8 850 const char *s = pv;
c4420975 851 const char * const send = pv + len;
ae776a2c 852 const char *d;
60939fb8 853 int numtype = 0;
60939fb8 854
3823048b 855 PERL_ARGS_ASSERT_GROK_NUMBER_FLAGS;
7918f24d 856
60939fb8
NC
857 while (s < send && isSPACE(*s))
858 s++;
859 if (s == send) {
860 return 0;
861 } else if (*s == '-') {
862 s++;
863 numtype = IS_NUMBER_NEG;
864 }
865 else if (*s == '+')
aa42a541 866 s++;
60939fb8
NC
867
868 if (s == send)
869 return 0;
870
ae776a2c 871 /* The first digit (after optional sign): note that might
8c12dc63 872 * also point to "infinity" or "nan", or "1.#INF". */
ae776a2c
JH
873 d = s;
874
8c12dc63 875 /* next must be digit or the radix separator or beginning of infinity/nan */
60939fb8
NC
876 if (isDIGIT(*s)) {
877 /* UVs are at least 32 bits, so the first 9 decimal digits cannot
878 overflow. */
879 UV value = *s - '0';
880 /* This construction seems to be more optimiser friendly.
881 (without it gcc does the isDIGIT test and the *s - '0' separately)
882 With it gcc on arm is managing 6 instructions (6 cycles) per digit.
883 In theory the optimiser could deduce how far to unroll the loop
884 before checking for overflow. */
58bb9ec3
NC
885 if (++s < send) {
886 int digit = *s - '0';
60939fb8
NC
887 if (digit >= 0 && digit <= 9) {
888 value = value * 10 + digit;
58bb9ec3
NC
889 if (++s < send) {
890 digit = *s - '0';
60939fb8
NC
891 if (digit >= 0 && digit <= 9) {
892 value = value * 10 + digit;
58bb9ec3
NC
893 if (++s < send) {
894 digit = *s - '0';
60939fb8
NC
895 if (digit >= 0 && digit <= 9) {
896 value = value * 10 + digit;
58bb9ec3
NC
897 if (++s < send) {
898 digit = *s - '0';
60939fb8
NC
899 if (digit >= 0 && digit <= 9) {
900 value = value * 10 + digit;
58bb9ec3
NC
901 if (++s < send) {
902 digit = *s - '0';
60939fb8
NC
903 if (digit >= 0 && digit <= 9) {
904 value = value * 10 + digit;
58bb9ec3
NC
905 if (++s < send) {
906 digit = *s - '0';
60939fb8
NC
907 if (digit >= 0 && digit <= 9) {
908 value = value * 10 + digit;
58bb9ec3
NC
909 if (++s < send) {
910 digit = *s - '0';
60939fb8
NC
911 if (digit >= 0 && digit <= 9) {
912 value = value * 10 + digit;
58bb9ec3
NC
913 if (++s < send) {
914 digit = *s - '0';
60939fb8
NC
915 if (digit >= 0 && digit <= 9) {
916 value = value * 10 + digit;
58bb9ec3 917 if (++s < send) {
60939fb8
NC
918 /* Now got 9 digits, so need to check
919 each time for overflow. */
58bb9ec3 920 digit = *s - '0';
60939fb8 921 while (digit >= 0 && digit <= 9
945b524a
JH
922 && (value < uv_max_div_10
923 || (value == uv_max_div_10
924 && digit <= uv_max_mod_10))) {
60939fb8 925 value = value * 10 + digit;
58bb9ec3
NC
926 if (++s < send)
927 digit = *s - '0';
60939fb8
NC
928 else
929 break;
930 }
931 if (digit >= 0 && digit <= 9
51bd16da 932 && (s < send)) {
60939fb8
NC
933 /* value overflowed.
934 skip the remaining digits, don't
935 worry about setting *valuep. */
936 do {
937 s++;
938 } while (s < send && isDIGIT(*s));
939 numtype |=
940 IS_NUMBER_GREATER_THAN_UV_MAX;
941 goto skip_value;
942 }
943 }
944 }
98994639 945 }
60939fb8
NC
946 }
947 }
948 }
949 }
950 }
951 }
952 }
953 }
954 }
955 }
956 }
98994639 957 }
60939fb8 958 }
98994639 959 }
60939fb8
NC
960 numtype |= IS_NUMBER_IN_UV;
961 if (valuep)
962 *valuep = value;
963
964 skip_value:
965 if (GROK_NUMERIC_RADIX(&s, send)) {
966 numtype |= IS_NUMBER_NOT_INT;
967 while (s < send && isDIGIT(*s)) /* optional digits after the radix */
968 s++;
98994639 969 }
60939fb8
NC
970 }
971 else if (GROK_NUMERIC_RADIX(&s, send)) {
972 numtype |= IS_NUMBER_NOT_INT | IS_NUMBER_IN_UV; /* valuep assigned below */
973 /* no digits before the radix means we need digits after it */
974 if (s < send && isDIGIT(*s)) {
975 do {
976 s++;
977 } while (s < send && isDIGIT(*s));
978 if (valuep) {
979 /* integer approximation is valid - it's 0. */
980 *valuep = 0;
981 }
98994639 982 }
60939fb8 983 else
ae776a2c 984 return 0;
ff4eb398 985 }
60939fb8 986
926f5fc6 987 if (s > d && s < send) {
60939fb8 988 /* we can have an optional exponent part */
305b8651 989 if (isALPHA_FOLD_EQ(*s, 'e')) {
60939fb8
NC
990 s++;
991 if (s < send && (*s == '-' || *s == '+'))
992 s++;
993 if (s < send && isDIGIT(*s)) {
994 do {
995 s++;
996 } while (s < send && isDIGIT(*s));
997 }
3f7602fa
TC
998 else if (flags & PERL_SCAN_TRAILING)
999 return numtype | IS_NUMBER_TRAILING;
60939fb8 1000 else
3f7602fa
TC
1001 return 0;
1002
1003 /* The only flag we keep is sign. Blow away any "it's UV" */
1004 numtype &= IS_NUMBER_NEG;
1005 numtype |= IS_NUMBER_NOT_INT;
60939fb8
NC
1006 }
1007 }
1008 while (s < send && isSPACE(*s))
1009 s++;
1010 if (s >= send)
aa8b85de 1011 return numtype;
60939fb8
NC
1012 if (len == 10 && memEQ(pv, "0 but true", 10)) {
1013 if (valuep)
1014 *valuep = 0;
1015 return IS_NUMBER_IN_UV;
1016 }
8c12dc63
JH
1017 /* We could be e.g. at "Inf" or "NaN", or at the "#" of "1.#INF". */
1018 if ((s + 2 < send) && strchr("inqs#", toFOLD(*s))) {
1019 /* Really detect inf/nan. Start at d, not s, since the above
1020 * code might have already consumed the "1." or "1". */
3823048b 1021 int infnan = Perl_grok_infnan(aTHX_ &d, send);
8c12dc63
JH
1022 if ((infnan & IS_NUMBER_INFINITY)) {
1023 return (numtype | infnan); /* Keep sign for infinity. */
1024 }
1025 else if ((infnan & IS_NUMBER_NAN)) {
1026 return (numtype | infnan) & ~IS_NUMBER_NEG; /* Clear sign for nan. */
1027 }
1028 }
3f7602fa
TC
1029 else if (flags & PERL_SCAN_TRAILING) {
1030 return numtype | IS_NUMBER_TRAILING;
1031 }
1032
60939fb8 1033 return 0;
98994639
HS
1034}
1035
6313e544 1036/*
73e43954 1037grok_atoUV
6313e544 1038
22ff3130 1039grok_atoUV parses a C-style zero-byte terminated string, looking for
d62b8c6a 1040a decimal unsigned integer.
338aa8b0 1041
d62b8c6a
JH
1042Returns the unsigned integer, if a valid value can be parsed
1043from the beginning of the string.
f4379102 1044
d62b8c6a 1045Accepts only the decimal digits '0'..'9'.
6313e544 1046
22ff3130 1047As opposed to atoi or strtol, grok_atoUV does NOT allow optional
d62b8c6a
JH
1048leading whitespace, or negative inputs. If such features are
1049required, the calling code needs to explicitly implement those.
6313e544 1050
22ff3130
HS
1051Returns true if a valid value could be parsed. In that case, valptr
1052is set to the parsed value, and endptr (if provided) is set to point
1053to the character after the last digit.
338aa8b0 1054
22ff3130
HS
1055Returns false otherwise. This can happen if a) there is a leading zero
1056followed by another digit; b) the digits would overflow a UV; or c)
1057there are trailing non-digits AND endptr is not provided.
6313e544 1058
d62b8c6a
JH
1059Background: atoi has severe problems with illegal inputs, it cannot be
1060used for incremental parsing, and therefore should be avoided
1061atoi and strtol are also affected by locale settings, which can also be
1062seen as a bug (global state controlled by user environment).
1063
6313e544
JH
1064*/
1065
22ff3130
HS
1066bool
1067Perl_grok_atoUV(const char *pv, UV *valptr, const char** endptr)
6313e544
JH
1068{
1069 const char* s = pv;
1070 const char** eptr;
1071 const char* end2; /* Used in case endptr is NULL. */
22ff3130 1072 UV val = 0; /* The parsed value. */
6313e544 1073
22ff3130 1074 PERL_ARGS_ASSERT_GROK_ATOUV;
6313e544
JH
1075
1076 eptr = endptr ? endptr : &end2;
75feedba
JH
1077 if (isDIGIT(*s)) {
1078 /* Single-digit inputs are quite common. */
6313e544 1079 val = *s++ - '0';
75feedba 1080 if (isDIGIT(*s)) {
22ff3130
HS
1081 /* Fail on extra leading zeros. */
1082 if (val == 0)
1083 return FALSE;
75feedba
JH
1084 while (isDIGIT(*s)) {
1085 /* This could be unrolled like in grok_number(), but
1086 * the expected uses of this are not speed-needy, and
1087 * unlikely to need full 64-bitness. */
1088 U8 digit = *s++ - '0';
945b524a
JH
1089 if (val < uv_max_div_10 ||
1090 (val == uv_max_div_10 && digit <= uv_max_mod_10)) {
75feedba
JH
1091 val = val * 10 + digit;
1092 } else {
22ff3130 1093 return FALSE;
6313e544 1094 }
6313e544
JH
1095 }
1096 }
75feedba 1097 }
22ff3130
HS
1098 if (s == pv)
1099 return FALSE;
1100 if (endptr == NULL && *s)
1101 return FALSE; /* If endptr is NULL, no trailing non-digits allowed. */
6313e544 1102 *eptr = s;
22ff3130
HS
1103 *valptr = val;
1104 return TRUE;
6313e544
JH
1105}
1106
a4eca1d4 1107#ifndef USE_QUADMATH
4801ca72 1108STATIC NV
98994639
HS
1109S_mulexp10(NV value, I32 exponent)
1110{
1111 NV result = 1.0;
1112 NV power = 10.0;
1113 bool negative = 0;
1114 I32 bit;
1115
1116 if (exponent == 0)
1117 return value;
659c4b96
DM
1118 if (value == 0)
1119 return (NV)0;
87032ba1 1120
24866caa 1121 /* On OpenVMS VAX we by default use the D_FLOAT double format,
67597c89 1122 * and that format does not have *easy* capabilities [1] for
24866caa
CB
1123 * overflowing doubles 'silently' as IEEE fp does. We also need
1124 * to support G_FLOAT on both VAX and Alpha, and though the exponent
1125 * range is much larger than D_FLOAT it still doesn't do silent
1126 * overflow. Therefore we need to detect early whether we would
1127 * overflow (this is the behaviour of the native string-to-float
1128 * conversion routines, and therefore of native applications, too).
67597c89 1129 *
24866caa
CB
1130 * [1] Trying to establish a condition handler to trap floating point
1131 * exceptions is not a good idea. */
87032ba1
JH
1132
1133 /* In UNICOS and in certain Cray models (such as T90) there is no
1134 * IEEE fp, and no way at all from C to catch fp overflows gracefully.
1135 * There is something you can do if you are willing to use some
1136 * inline assembler: the instruction is called DFI-- but that will
1137 * disable *all* floating point interrupts, a little bit too large
1138 * a hammer. Therefore we need to catch potential overflows before
1139 * it's too late. */
353813d9 1140
85bba25f 1141#if ((defined(VMS) && !defined(_IEEE_FP)) || defined(_UNICOS)) && defined(NV_MAX_10_EXP)
353813d9 1142 STMT_START {
c4420975 1143 const NV exp_v = log10(value);
353813d9
HS
1144 if (exponent >= NV_MAX_10_EXP || exponent + exp_v >= NV_MAX_10_EXP)
1145 return NV_MAX;
1146 if (exponent < 0) {
1147 if (-(exponent + exp_v) >= NV_MAX_10_EXP)
1148 return 0.0;
1149 while (-exponent >= NV_MAX_10_EXP) {
1150 /* combination does not overflow, but 10^(-exponent) does */
1151 value /= 10;
1152 ++exponent;
1153 }
1154 }
1155 } STMT_END;
87032ba1
JH
1156#endif
1157
353813d9
HS
1158 if (exponent < 0) {
1159 negative = 1;
1160 exponent = -exponent;
b27804d8
DM
1161#ifdef NV_MAX_10_EXP
1162 /* for something like 1234 x 10^-309, the action of calculating
1163 * the intermediate value 10^309 then returning 1234 / (10^309)
1164 * will fail, since 10^309 becomes infinity. In this case try to
1165 * refactor it as 123 / (10^308) etc.
1166 */
1167 while (value && exponent > NV_MAX_10_EXP) {
1168 exponent--;
1169 value /= 10;
1170 }
48853916
JH
1171 if (value == 0.0)
1172 return value;
b27804d8 1173#endif
353813d9 1174 }
c62e754c
JH
1175#if defined(__osf__)
1176 /* Even with cc -ieee + ieee_set_fp_control(IEEE_TRAP_ENABLE_INV)
1177 * Tru64 fp behavior on inf/nan is somewhat broken. Another way
1178 * to do this would be ieee_set_fp_control(IEEE_TRAP_ENABLE_OVF)
1179 * but that breaks another set of infnan.t tests. */
1180# define FP_OVERFLOWS_TO_ZERO
1181#endif
98994639
HS
1182 for (bit = 1; exponent; bit <<= 1) {
1183 if (exponent & bit) {
1184 exponent ^= bit;
1185 result *= power;
c62e754c
JH
1186#ifdef FP_OVERFLOWS_TO_ZERO
1187 if (result == 0)
1188 return value < 0 ? -NV_INF : NV_INF;
1189#endif
236f0012
CB
1190 /* Floating point exceptions are supposed to be turned off,
1191 * but if we're obviously done, don't risk another iteration.
1192 */
1193 if (exponent == 0) break;
98994639
HS
1194 }
1195 power *= power;
1196 }
1197 return negative ? value / result : value * result;
1198}
a4eca1d4 1199#endif /* #ifndef USE_QUADMATH */
98994639
HS
1200
1201NV
1202Perl_my_atof(pTHX_ const char* s)
1203{
1204 NV x = 0.0;
a4eca1d4
JH
1205#ifdef USE_QUADMATH
1206 Perl_my_atof2(aTHX_ s, &x);
1207 return x;
1208#else
1209# ifdef USE_LOCALE_NUMERIC
7918f24d
NC
1210 PERL_ARGS_ASSERT_MY_ATOF;
1211
a2287a13 1212 {
67d796ae
KW
1213 DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
1214 STORE_LC_NUMERIC_SET_TO_NEEDED();
d6ded950 1215 if (PL_numeric_radix_sv && IN_LC(LC_NUMERIC)) {
e4850248
KW
1216 const char *standard = NULL, *local = NULL;
1217 bool use_standard_radix;
98994639 1218
e4850248
KW
1219 /* Look through the string for the first thing that looks like a
1220 * decimal point: either the value in the current locale or the
1221 * standard fallback of '.'. The one which appears earliest in the
1222 * input string is the one that we should have atof look for. Note
1223 * that we have to determine this beforehand because on some
1224 * systems, Perl_atof2 is just a wrapper around the system's atof.
1225 * */
1226 standard = strchr(s, '.');
1227 local = strstr(s, SvPV_nolen(PL_numeric_radix_sv));
78787052 1228
e4850248 1229 use_standard_radix = standard && (!local || standard < local);
78787052 1230
e4850248
KW
1231 if (use_standard_radix)
1232 SET_NUMERIC_STANDARD();
78787052 1233
e4850248 1234 Perl_atof2(s, x);
78787052 1235
e4850248 1236 if (use_standard_radix)
67d796ae 1237 SET_NUMERIC_UNDERLYING();
e4850248
KW
1238 }
1239 else
1240 Perl_atof2(s, x);
a2287a13
KW
1241 RESTORE_LC_NUMERIC();
1242 }
a4eca1d4 1243# else
a36244b7 1244 Perl_atof2(s, x);
a4eca1d4 1245# endif
98994639
HS
1246#endif
1247 return x;
1248}
1249
3c81f0b3
DD
1250
1251#ifdef USING_MSVC6
1252# pragma warning(push)
1253# pragma warning(disable:4756;disable:4056)
1254#endif
829757a4 1255static char*
5563f457 1256S_my_atof_infnan(pTHX_ const char* s, bool negative, const char* send, NV* value)
829757a4
JH
1257{
1258 const char *p0 = negative ? s - 1 : s;
1259 const char *p = p0;
3823048b 1260 int infnan = grok_infnan(&p, send);
829757a4
JH
1261 if (infnan && p != p0) {
1262 /* If we can generate inf/nan directly, let's do so. */
1263#ifdef NV_INF
1264 if ((infnan & IS_NUMBER_INFINITY)) {
3823048b 1265 *value = (infnan & IS_NUMBER_NEG) ? -NV_INF: NV_INF;
829757a4
JH
1266 return (char*)p;
1267 }
1268#endif
1269#ifdef NV_NAN
1270 if ((infnan & IS_NUMBER_NAN)) {
3823048b 1271 *value = NV_NAN;
829757a4
JH
1272 return (char*)p;
1273 }
1274#endif
1275#ifdef Perl_strtod
68611e6f 1276 /* If still here, we didn't have either NV_INF or NV_NAN,
829757a4
JH
1277 * and can try falling back to native strtod/strtold.
1278 *
68611e6f
JH
1279 * (Though, are our NV_INF or NV_NAN ever not defined?)
1280 *
829757a4
JH
1281 * The native interface might not recognize all the possible
1282 * inf/nan strings Perl recognizes. What we can try
1283 * is to try faking the input. We will try inf/-inf/nan
1284 * as the most promising/portable input. */
1285 {
1286 const char* fake = NULL;
1287 char* endp;
1288 NV nv;
1289 if ((infnan & IS_NUMBER_INFINITY)) {
1290 fake = ((infnan & IS_NUMBER_NEG)) ? "-inf" : "inf";
1291 }
1292 else if ((infnan & IS_NUMBER_NAN)) {
1293 fake = "nan";
1294 }
1295 assert(fake);
1296 nv = Perl_strtod(fake, &endp);
1297 if (fake != endp) {
1298 if ((infnan & IS_NUMBER_INFINITY)) {
1299#ifdef Perl_isinf
1300 if (Perl_isinf(nv))
1301 *value = nv;
1302#else
1303 /* last resort, may generate SIGFPE */
1304 *value = Perl_exp((NV)1e9);
1305 if ((infnan & IS_NUMBER_NEG))
1306 *value = -*value;
1307#endif
1308 return (char*)p; /* p, not endp */
1309 }
1310 else if ((infnan & IS_NUMBER_NAN)) {
1311#ifdef Perl_isnan
1312 if (Perl_isnan(nv))
1313 *value = nv;
1314#else
1315 /* last resort, may generate SIGFPE */
1316 *value = Perl_log((NV)-1.0);
1317#endif
1318 return (char*)p; /* p, not endp */
1319 }
1320 }
1321 }
1322#endif /* #ifdef Perl_strtod */
1323 }
1324 return NULL;
1325}
3c81f0b3
DD
1326#ifdef USING_MSVC6
1327# pragma warning(pop)
1328#endif
829757a4 1329
98994639
HS
1330char*
1331Perl_my_atof2(pTHX_ const char* orig, NV* value)
1332{
e1ec3a88 1333 const char* s = orig;
a4eca1d4
JH
1334 NV result[3] = {0.0, 0.0, 0.0};
1335#if defined(USE_PERL_ATOF) || defined(USE_QUADMATH)
ae776a2c 1336 const char* send = s + strlen(orig); /* one past the last */
a4eca1d4
JH
1337 bool negative = 0;
1338#endif
1339#if defined(USE_PERL_ATOF) && !defined(USE_QUADMATH)
1340 UV accumulator[2] = {0,0}; /* before/after dp */
8194bf88 1341 bool seen_digit = 0;
20f6aaab
AS
1342 I32 exp_adjust[2] = {0,0};
1343 I32 exp_acc[2] = {-1, -1};
1344 /* the current exponent adjust for the accumulators */
98994639 1345 I32 exponent = 0;
8194bf88 1346 I32 seen_dp = 0;
20f6aaab
AS
1347 I32 digit = 0;
1348 I32 old_digit = 0;
8194bf88 1349 I32 sig_digits = 0; /* noof significant digits seen so far */
a4eca1d4 1350#endif
8194bf88 1351
a4eca1d4 1352#if defined(USE_PERL_ATOF) || defined(USE_QUADMATH)
7918f24d
NC
1353 PERL_ARGS_ASSERT_MY_ATOF2;
1354
a4eca1d4
JH
1355 /* leading whitespace */
1356 while (isSPACE(*s))
1357 ++s;
1358
1359 /* sign */
1360 switch (*s) {
1361 case '-':
1362 negative = 1;
1363 /* FALLTHROUGH */
1364 case '+':
1365 ++s;
1366 }
1367#endif
1368
1369#ifdef USE_QUADMATH
1370 {
1371 char* endp;
adc55e02 1372 if ((endp = S_my_atof_infnan(aTHX_ s, negative, send, value)))
a4eca1d4
JH
1373 return endp;
1374 result[2] = strtoflt128(s, &endp);
1375 if (s != endp) {
1376 *value = negative ? -result[2] : result[2];
1377 return endp;
1378 }
1379 return NULL;
1380 }
1381#elif defined(USE_PERL_ATOF)
1382
8194bf88
DM
1383/* There is no point in processing more significant digits
1384 * than the NV can hold. Note that NV_DIG is a lower-bound value,
1385 * while we need an upper-bound value. We add 2 to account for this;
1386 * since it will have been conservative on both the first and last digit.
1387 * For example a 32-bit mantissa with an exponent of 4 would have
1388 * exact values in the set
1389 * 4
1390 * 8
1391 * ..
1392 * 17179869172
1393 * 17179869176
1394 * 17179869180
1395 *
1396 * where for the purposes of calculating NV_DIG we would have to discount
1397 * both the first and last digit, since neither can hold all values from
1398 * 0..9; but for calculating the value we must examine those two digits.
1399 */
ffa277e5
EAS
1400#ifdef MAX_SIG_DIG_PLUS
1401 /* It is not necessarily the case that adding 2 to NV_DIG gets all the
1402 possible digits in a NV, especially if NVs are not IEEE compliant
1403 (e.g., long doubles on IRIX) - Allen <allens@cpan.org> */
1404# define MAX_SIG_DIGITS (NV_DIG+MAX_SIG_DIG_PLUS)
1405#else
1406# define MAX_SIG_DIGITS (NV_DIG+2)
1407#endif
8194bf88
DM
1408
1409/* the max number we can accumulate in a UV, and still safely do 10*N+9 */
1410#define MAX_ACCUMULATE ( (UV) ((UV_MAX - 9)/10))
98994639 1411
ae776a2c 1412 {
829757a4 1413 const char* endp;
5563f457 1414 if ((endp = S_my_atof_infnan(aTHX_ s, negative, send, value)))
829757a4 1415 return (char*)endp;
ae776a2c 1416 }
2b54f59f 1417
8194bf88
DM
1418 /* we accumulate digits into an integer; when this becomes too
1419 * large, we add the total to NV and start again */
98994639 1420
8194bf88
DM
1421 while (1) {
1422 if (isDIGIT(*s)) {
1423 seen_digit = 1;
20f6aaab 1424 old_digit = digit;
8194bf88 1425 digit = *s++ - '0';
20f6aaab
AS
1426 if (seen_dp)
1427 exp_adjust[1]++;
98994639 1428
8194bf88
DM
1429 /* don't start counting until we see the first significant
1430 * digit, eg the 5 in 0.00005... */
1431 if (!sig_digits && digit == 0)
1432 continue;
1433
1434 if (++sig_digits > MAX_SIG_DIGITS) {
98994639 1435 /* limits of precision reached */
20f6aaab
AS
1436 if (digit > 5) {
1437 ++accumulator[seen_dp];
1438 } else if (digit == 5) {
1439 if (old_digit % 2) { /* round to even - Allen */
1440 ++accumulator[seen_dp];
1441 }
1442 }
1443 if (seen_dp) {
1444 exp_adjust[1]--;
1445 } else {
1446 exp_adjust[0]++;
1447 }
8194bf88 1448 /* skip remaining digits */
98994639 1449 while (isDIGIT(*s)) {
98994639 1450 ++s;
20f6aaab
AS
1451 if (! seen_dp) {
1452 exp_adjust[0]++;
1453 }
98994639
HS
1454 }
1455 /* warn of loss of precision? */
98994639 1456 }
8194bf88 1457 else {
20f6aaab 1458 if (accumulator[seen_dp] > MAX_ACCUMULATE) {
8194bf88 1459 /* add accumulator to result and start again */
20f6aaab
AS
1460 result[seen_dp] = S_mulexp10(result[seen_dp],
1461 exp_acc[seen_dp])
1462 + (NV)accumulator[seen_dp];
1463 accumulator[seen_dp] = 0;
1464 exp_acc[seen_dp] = 0;
98994639 1465 }
20f6aaab
AS
1466 accumulator[seen_dp] = accumulator[seen_dp] * 10 + digit;
1467 ++exp_acc[seen_dp];
98994639 1468 }
8194bf88 1469 }
e1ec3a88 1470 else if (!seen_dp && GROK_NUMERIC_RADIX(&s, send)) {
8194bf88 1471 seen_dp = 1;
20f6aaab 1472 if (sig_digits > MAX_SIG_DIGITS) {
c86f7df5 1473 do {
20f6aaab 1474 ++s;
c86f7df5 1475 } while (isDIGIT(*s));
20f6aaab
AS
1476 break;
1477 }
8194bf88
DM
1478 }
1479 else {
1480 break;
98994639
HS
1481 }
1482 }
1483
20f6aaab
AS
1484 result[0] = S_mulexp10(result[0], exp_acc[0]) + (NV)accumulator[0];
1485 if (seen_dp) {
1486 result[1] = S_mulexp10(result[1], exp_acc[1]) + (NV)accumulator[1];
1487 }
98994639 1488
305b8651 1489 if (seen_digit && (isALPHA_FOLD_EQ(*s, 'e'))) {
98994639
HS
1490 bool expnegative = 0;
1491
1492 ++s;
1493 switch (*s) {
1494 case '-':
1495 expnegative = 1;
924ba076 1496 /* FALLTHROUGH */
98994639
HS
1497 case '+':
1498 ++s;
1499 }
1500 while (isDIGIT(*s))
1501 exponent = exponent * 10 + (*s++ - '0');
1502 if (expnegative)
1503 exponent = -exponent;
1504 }
1505
20f6aaab
AS
1506
1507
98994639 1508 /* now apply the exponent */
20f6aaab
AS
1509
1510 if (seen_dp) {
1511 result[2] = S_mulexp10(result[0],exponent+exp_adjust[0])
1512 + S_mulexp10(result[1],exponent-exp_adjust[1]);
1513 } else {
1514 result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]);
1515 }
98994639
HS
1516
1517 /* now apply the sign */
1518 if (negative)
20f6aaab 1519 result[2] = -result[2];
a36244b7 1520#endif /* USE_PERL_ATOF */
20f6aaab 1521 *value = result[2];
73d840c0 1522 return (char *)s;
98994639
HS
1523}
1524
5d34af89 1525/*
3d9d9213 1526=for apidoc isinfnan
5d34af89
JH
1527
1528Perl_isinfnan() is utility function that returns true if the NV
1529argument is either an infinity or a NaN, false otherwise. To test
1530in more detail, use Perl_isinf() and Perl_isnan().
1531
68611e6f
JH
1532This is also the logical inverse of Perl_isfinite().
1533
5d34af89
JH
1534=cut
1535*/
1cd88304
JH
1536bool
1537Perl_isinfnan(NV nv)
1538{
1539#ifdef Perl_isinf
1540 if (Perl_isinf(nv))
1541 return TRUE;
1542#endif
1543#ifdef Perl_isnan
1544 if (Perl_isnan(nv))
1545 return TRUE;
1546#endif
1547 return FALSE;
1548}
1549
354b74ae
FC
1550/*
1551=for apidoc
1552
1553Checks whether the argument would be either an infinity or NaN when used
1554as a number, but is careful not to trigger non-numeric or uninitialized
1555warnings. it assumes the caller has done SvGETMAGIC(sv) already.
1556
1557=cut
1558*/
1559
1560bool
1561Perl_isinfnansv(pTHX_ SV *sv)
1562{
1563 PERL_ARGS_ASSERT_ISINFNANSV;
1564 if (!SvOK(sv))
1565 return FALSE;
1566 if (SvNOKp(sv))
1567 return Perl_isinfnan(SvNVX(sv));
1568 if (SvIOKp(sv))
1569 return FALSE;
1570 {
1571 STRLEN len;
1572 const char *s = SvPV_nomg_const(sv, len);
3823048b 1573 return cBOOL(grok_infnan(&s, s+len));
354b74ae
FC
1574 }
1575}
1576
d67dac15 1577#ifndef HAS_MODFL
68611e6f
JH
1578/* C99 has truncl, pre-C99 Solaris had aintl. We can use either with
1579 * copysignl to emulate modfl, which is in some platforms missing or
1580 * broken. */
d67dac15
JH
1581# if defined(HAS_TRUNCL) && defined(HAS_COPYSIGNL)
1582long double
1583Perl_my_modfl(long double x, long double *ip)
1584{
68611e6f
JH
1585 *ip = truncl(x);
1586 return (x == *ip ? copysignl(0.0L, x) : x - *ip);
d67dac15
JH
1587}
1588# elif defined(HAS_AINTL) && defined(HAS_COPYSIGNL)
55954f19
JH
1589long double
1590Perl_my_modfl(long double x, long double *ip)
1591{
68611e6f
JH
1592 *ip = aintl(x);
1593 return (x == *ip ? copysignl(0.0L, x) : x - *ip);
55954f19 1594}
d67dac15 1595# endif
55954f19
JH
1596#endif
1597
7b9b7dff 1598/* Similarly, with ilogbl and scalbnl we can emulate frexpl. */
55954f19
JH
1599#if ! defined(HAS_FREXPL) && defined(HAS_ILOGBL) && defined(HAS_SCALBNL)
1600long double
1601Perl_my_frexpl(long double x, int *e) {
68611e6f
JH
1602 *e = x == 0.0L ? 0 : ilogbl(x) + 1;
1603 return (scalbnl(x, -*e));
55954f19
JH
1604}
1605#endif
66610fdd
RGS
1606
1607/*
ed140128
AD
1608=for apidoc Perl_signbit
1609
1610Return a non-zero integer if the sign bit on an NV is set, and 0 if
1611it is not.
1612
1613If Configure detects this system has a signbit() that will work with
1614our NVs, then we just use it via the #define in perl.h. Otherwise,
8b7fad81
JH
1615fall back on this implementation. The main use of this function
1616is catching -0.0.
ed140128
AD
1617
1618Configure notes: This function is called 'Perl_signbit' instead of a
1619plain 'signbit' because it is easy to imagine a system having a signbit()
1620function or macro that doesn't happen to work with our particular choice
1621of NVs. We shouldn't just re-#define signbit as Perl_signbit and expect
1622the standard system headers to be happy. Also, this is a no-context
1623function (no pTHX_) because Perl_signbit() is usually re-#defined in
1624perl.h as a simple macro call to the system's signbit().
1625Users should just always call Perl_signbit().
1626
1627=cut
1628*/
1629#if !defined(HAS_SIGNBIT)
1630int
1631Perl_signbit(NV x) {
8b7fad81
JH
1632# ifdef Perl_fp_class_nzero
1633 if (x == 0)
1634 return Perl_fp_class_nzero(x);
8b7fad81 1635# endif
3585840c 1636 return (x < 0.0) ? 1 : 0;
ed140128
AD
1637}
1638#endif
1639
1640/*
14d04a33 1641 * ex: set ts=8 sts=4 sw=4 et:
37442d52 1642 */