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[perl5.git] / numeric.c
CommitLineData
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
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16 */
17
ccfc67b7
JH
18/*
19=head1 Numeric functions
166f8a29 20
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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
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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
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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
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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
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253
254Not documented yet because experimental is C<PERL_SCAN_SILENT_NON_PORTABLE
255which suppresses any message for non-portable numbers that are still valid
256on this platform.
53305cf1
NC
257 */
258
259UV
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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)) {
21431899
KW
525 DECLARE_STORE_LC_NUMERIC_SET_TO_NEEDED();
526 if (PL_numeric_radix_sv) {
c5a7e38e
KW
527 STRLEN len;
528 const char * const radix = SvPV(PL_numeric_radix_sv, len);
529 if (*sp + len <= send && memEQ(*sp, radix, len)) {
530 *sp += len;
531 RESTORE_LC_NUMERIC();
532 return TRUE;
533 }
21431899
KW
534 }
535 RESTORE_LC_NUMERIC();
98994639
HS
536 }
537 /* always try "." if numeric radix didn't match because
538 * we may have data from different locales mixed */
539#endif
7918f24d
NC
540
541 PERL_ARGS_ASSERT_GROK_NUMERIC_RADIX;
542
98994639
HS
543 if (*sp < send && **sp == '.') {
544 ++*sp;
545 return TRUE;
546 }
547 return FALSE;
548}
549
550/*
3f7602fa 551=for apidoc grok_number_flags
98994639
HS
552
553Recognise (or not) a number. The type of the number is returned
554(0 if unrecognised), otherwise it is a bit-ORed combination of
555IS_NUMBER_IN_UV, IS_NUMBER_GREATER_THAN_UV_MAX, IS_NUMBER_NOT_INT,
aa8b85de 556IS_NUMBER_NEG, IS_NUMBER_INFINITY, IS_NUMBER_NAN (defined in perl.h).
60939fb8 557
cd164854 558If the value of the number can fit in a UV, it is returned in the *valuep
60939fb8
NC
559IS_NUMBER_IN_UV will be set to indicate that *valuep is valid, IS_NUMBER_IN_UV
560will never be set unless *valuep is valid, but *valuep may have been assigned
561to during processing even though IS_NUMBER_IN_UV is not set on return.
562If valuep is NULL, IS_NUMBER_IN_UV will be set for the same cases as when
563valuep is non-NULL, but no actual assignment (or SEGV) will occur.
564
565IS_NUMBER_NOT_INT will be set with IS_NUMBER_IN_UV if trailing decimals were
566seen (in which case *valuep gives the true value truncated to an integer), and
567IS_NUMBER_NEG if the number is negative (in which case *valuep holds the
568absolute value). IS_NUMBER_IN_UV is not set if e notation was used or the
569number is larger than a UV.
98994639 570
3f7602fa
TC
571C<flags> allows only C<PERL_SCAN_TRAILING>, which allows for trailing
572non-numeric text on an otherwise successful I<grok>, setting
573C<IS_NUMBER_TRAILING> on the result.
574
575=for apidoc grok_number
576
577Identical to grok_number_flags() with flags set to zero.
578
98994639
HS
579=cut
580 */
581int
582Perl_grok_number(pTHX_ const char *pv, STRLEN len, UV *valuep)
583{
3f7602fa
TC
584 PERL_ARGS_ASSERT_GROK_NUMBER;
585
586 return grok_number_flags(pv, len, valuep, 0);
587}
588
ae776a2c 589/* Peek ahead to see whether this could be Inf/NaN/qNaN/snan/1.#INF */
9ff909cf
JH
590#define INFNAN_PEEK(s, send) \
591 (s < send && \
592 ((isALPHA_FOLD_EQ(*s, 'I') || isALPHA_FOLD_EQ(*s, 'N')) || \
593 ((s + 4) < send && \
594 (isALPHA_FOLD_EQ(*s, 'Q') || isALPHA_FOLD_EQ(*s, 'S')) && \
595 isALPHA_FOLD_EQ(s[1], 'N')) || \
596 ((s + 5) < send && \
597 (*s == '1' && ((s[1] == '.' && s[2] == '#') || s[1] == '#')))))
ae776a2c 598
ff4eb398
JH
599/*
600=for apidoc grok_infnan
601
602Helper for grok_number(), accepts various ways of spelling "infinity"
603or "not a number", and returns one of the following flag combinations:
604
605 IS_NUMBER_INFINITE
606 IS_NUMBER_NAN
607 IS_NUMBER_INFINITE | IS_NUMBER_NEG
608 IS_NUMBER_NAN | IS_NUMBER_NEG
609 0
610
611If an infinity or not-a-number is recognized, the *sp will point to
612one past the end of the recognized string. If the recognition fails,
613zero is returned, and the *sp will not move.
614
615=cut
616*/
617
618int
619Perl_grok_infnan(const char** sp, const char* send)
620{
621 const char* s = *sp;
622 int flags = 0;
623
624 PERL_ARGS_ASSERT_GROK_INFNAN;
625
626 if (*s == '-') {
627 flags |= IS_NUMBER_NEG; /* Yes, -NaN happens. Incorrect but happens. */
628 s++; if (s == send) return 0;
629 }
630
631 if (*s == '1') {
632 /* Visual C: 1.#SNAN, -1.#QNAN, 1#INF, 1#.IND (maybe also 1.#NAN) */
633 s++; if (s == send) return 0;
634 if (*s == '.') {
635 s++; if (s == send) return 0;
636 }
637 if (*s == '#') {
638 s++; if (s == send) return 0;
639 } else
640 return 0;
641 }
642
305b8651 643 if (isALPHA_FOLD_EQ(*s, 'I')) {
ff4eb398 644 /* INF or IND (1.#IND is indeterminate, a certain type of NAN) */
305b8651 645 s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0;
ff4eb398 646 s++; if (s == send) return 0;
305b8651 647 if (isALPHA_FOLD_EQ(*s, 'F')) {
ff4eb398 648 s++;
305b8651
KW
649 if (s < send && (isALPHA_FOLD_EQ(*s, 'I'))) {
650 s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0;
651 s++; if (s == send || isALPHA_FOLD_NE(*s, 'I')) return 0;
652 s++; if (s == send || isALPHA_FOLD_NE(*s, 'T')) return 0;
ff4eb398 653 /* XXX maybe also grok "infinite"? */
305b8651 654 s++; if (s == send || isALPHA_FOLD_NE(*s, 'Y')) return 0;
ff4eb398
JH
655 s++;
656 } else if (*s)
657 return 0;
658 flags |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT;
659 }
305b8651 660 else if (isALPHA_FOLD_EQ(*s, 'D')) {
ff4eb398
JH
661 s++;
662 flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT;
663 } else
664 return 0;
665
666 *sp = s;
667 return flags;
668 }
669 else {
670 /* NAN */
305b8651 671 if (isALPHA_FOLD_EQ(*s, 'S') || isALPHA_FOLD_EQ(*s, 'Q')) {
ff4eb398
JH
672 /* snan, qNaN */
673 /* XXX do something with the snan/qnan difference */
ae776a2c 674 s++; if (s == send) return 0;
ff4eb398
JH
675 }
676
305b8651
KW
677 if (isALPHA_FOLD_EQ(*s, 'N')) {
678 s++; if (s == send || isALPHA_FOLD_NE(*s, 'A')) return 0;
679 s++; if (s == send || isALPHA_FOLD_NE(*s, 'N')) return 0;
ff4eb398
JH
680 s++;
681
ae776a2c
JH
682 flags |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT;
683
ff4eb398
JH
684 /* NaN can be followed by various stuff since there are
685 * multiple different NaN values, and some implementations
ae776a2c
JH
686 * output the "payload" values, e.g. NaN123, NAN(abc),
687 * some implementation just have weird stuff like NaN%. */
688 s = send;
ff4eb398 689 }
ae776a2c
JH
690 else
691 return 0;
ff4eb398
JH
692
693 *sp = s;
694 return flags;
695 }
696
697 return 0;
698}
699
945b524a
JH
700static const UV uv_max_div_10 = UV_MAX / 10;
701static const U8 uv_max_mod_10 = UV_MAX % 10;
702
3f7602fa
TC
703int
704Perl_grok_number_flags(pTHX_ const char *pv, STRLEN len, UV *valuep, U32 flags)
705{
60939fb8 706 const char *s = pv;
c4420975 707 const char * const send = pv + len;
ae776a2c 708 const char *d;
60939fb8
NC
709 int numtype = 0;
710 int sawinf = 0;
aa8b85de 711 int sawnan = 0;
60939fb8 712
3f7602fa 713 PERL_ARGS_ASSERT_GROK_NUMBER_FLAGS;
7918f24d 714
60939fb8
NC
715 while (s < send && isSPACE(*s))
716 s++;
717 if (s == send) {
718 return 0;
719 } else if (*s == '-') {
720 s++;
721 numtype = IS_NUMBER_NEG;
722 }
723 else if (*s == '+')
aa42a541 724 s++;
60939fb8
NC
725
726 if (s == send)
727 return 0;
728
ae776a2c
JH
729 /* The first digit (after optional sign): note that might
730 * also point to "infinity" or "nan". */
731 d = s;
732
60939fb8
NC
733 /* next must be digit or the radix separator or beginning of infinity */
734 if (isDIGIT(*s)) {
735 /* UVs are at least 32 bits, so the first 9 decimal digits cannot
736 overflow. */
737 UV value = *s - '0';
738 /* This construction seems to be more optimiser friendly.
739 (without it gcc does the isDIGIT test and the *s - '0' separately)
740 With it gcc on arm is managing 6 instructions (6 cycles) per digit.
741 In theory the optimiser could deduce how far to unroll the loop
742 before checking for overflow. */
58bb9ec3
NC
743 if (++s < send) {
744 int digit = *s - '0';
60939fb8
NC
745 if (digit >= 0 && digit <= 9) {
746 value = value * 10 + digit;
58bb9ec3
NC
747 if (++s < send) {
748 digit = *s - '0';
60939fb8
NC
749 if (digit >= 0 && digit <= 9) {
750 value = value * 10 + digit;
58bb9ec3
NC
751 if (++s < send) {
752 digit = *s - '0';
60939fb8
NC
753 if (digit >= 0 && digit <= 9) {
754 value = value * 10 + digit;
58bb9ec3
NC
755 if (++s < send) {
756 digit = *s - '0';
60939fb8
NC
757 if (digit >= 0 && digit <= 9) {
758 value = value * 10 + digit;
58bb9ec3
NC
759 if (++s < send) {
760 digit = *s - '0';
60939fb8
NC
761 if (digit >= 0 && digit <= 9) {
762 value = value * 10 + digit;
58bb9ec3
NC
763 if (++s < send) {
764 digit = *s - '0';
60939fb8
NC
765 if (digit >= 0 && digit <= 9) {
766 value = value * 10 + digit;
58bb9ec3
NC
767 if (++s < send) {
768 digit = *s - '0';
60939fb8
NC
769 if (digit >= 0 && digit <= 9) {
770 value = value * 10 + digit;
58bb9ec3
NC
771 if (++s < send) {
772 digit = *s - '0';
60939fb8
NC
773 if (digit >= 0 && digit <= 9) {
774 value = value * 10 + digit;
58bb9ec3 775 if (++s < send) {
60939fb8
NC
776 /* Now got 9 digits, so need to check
777 each time for overflow. */
58bb9ec3 778 digit = *s - '0';
60939fb8 779 while (digit >= 0 && digit <= 9
945b524a
JH
780 && (value < uv_max_div_10
781 || (value == uv_max_div_10
782 && digit <= uv_max_mod_10))) {
60939fb8 783 value = value * 10 + digit;
58bb9ec3
NC
784 if (++s < send)
785 digit = *s - '0';
60939fb8
NC
786 else
787 break;
788 }
789 if (digit >= 0 && digit <= 9
51bd16da 790 && (s < send)) {
60939fb8
NC
791 /* value overflowed.
792 skip the remaining digits, don't
793 worry about setting *valuep. */
794 do {
795 s++;
796 } while (s < send && isDIGIT(*s));
797 numtype |=
798 IS_NUMBER_GREATER_THAN_UV_MAX;
799 goto skip_value;
800 }
801 }
802 }
98994639 803 }
60939fb8
NC
804 }
805 }
806 }
807 }
808 }
809 }
810 }
811 }
812 }
813 }
814 }
98994639 815 }
60939fb8 816 }
98994639 817 }
60939fb8
NC
818 numtype |= IS_NUMBER_IN_UV;
819 if (valuep)
820 *valuep = value;
821
822 skip_value:
823 if (GROK_NUMERIC_RADIX(&s, send)) {
824 numtype |= IS_NUMBER_NOT_INT;
825 while (s < send && isDIGIT(*s)) /* optional digits after the radix */
826 s++;
98994639 827 }
60939fb8
NC
828 }
829 else if (GROK_NUMERIC_RADIX(&s, send)) {
830 numtype |= IS_NUMBER_NOT_INT | IS_NUMBER_IN_UV; /* valuep assigned below */
831 /* no digits before the radix means we need digits after it */
832 if (s < send && isDIGIT(*s)) {
833 do {
834 s++;
835 } while (s < send && isDIGIT(*s));
836 if (valuep) {
837 /* integer approximation is valid - it's 0. */
838 *valuep = 0;
839 }
98994639 840 }
60939fb8 841 else
ae776a2c 842 return 0;
ff4eb398
JH
843 }
844 else {
9ff909cf 845 if (INFNAN_PEEK(d, send)) {
ae776a2c
JH
846 int infnan = Perl_grok_infnan(&d, send);
847 if ((infnan & IS_NUMBER_INFINITY)) {
848 numtype |= infnan;
849 sawinf = 1;
850 }
851 else if ((infnan & IS_NUMBER_NAN)) {
852 numtype |= infnan;
853 sawnan = 1;
854 }
855 else
856 return 0;
857 s = d;
ff4eb398 858 }
ff4eb398 859 }
60939fb8
NC
860
861 if (sawinf) {
ff4eb398 862 /* Keep the sign for infinity. */
60939fb8 863 numtype |= IS_NUMBER_INFINITY | IS_NUMBER_NOT_INT;
aa8b85de 864 } else if (sawnan) {
ff4eb398 865 numtype &= IS_NUMBER_NEG; /* Clear sign for nan. */
aa8b85de 866 numtype |= IS_NUMBER_NAN | IS_NUMBER_NOT_INT;
60939fb8
NC
867 } else if (s < send) {
868 /* we can have an optional exponent part */
305b8651 869 if (isALPHA_FOLD_EQ(*s, 'e')) {
60939fb8
NC
870 s++;
871 if (s < send && (*s == '-' || *s == '+'))
872 s++;
873 if (s < send && isDIGIT(*s)) {
874 do {
875 s++;
876 } while (s < send && isDIGIT(*s));
877 }
3f7602fa
TC
878 else if (flags & PERL_SCAN_TRAILING)
879 return numtype | IS_NUMBER_TRAILING;
60939fb8 880 else
3f7602fa
TC
881 return 0;
882
883 /* The only flag we keep is sign. Blow away any "it's UV" */
884 numtype &= IS_NUMBER_NEG;
885 numtype |= IS_NUMBER_NOT_INT;
60939fb8
NC
886 }
887 }
888 while (s < send && isSPACE(*s))
889 s++;
890 if (s >= send)
aa8b85de 891 return numtype;
60939fb8
NC
892 if (len == 10 && memEQ(pv, "0 but true", 10)) {
893 if (valuep)
894 *valuep = 0;
895 return IS_NUMBER_IN_UV;
896 }
3f7602fa
TC
897 else if (flags & PERL_SCAN_TRAILING) {
898 return numtype | IS_NUMBER_TRAILING;
899 }
900
60939fb8 901 return 0;
98994639
HS
902}
903
6313e544 904/*
d62b8c6a 905=for apidoc grok_atou
6313e544 906
d62b8c6a 907grok_atou is a safer replacement for atoi and strtol.
6313e544 908
d62b8c6a
JH
909grok_atou parses a C-style zero-byte terminated string, looking for
910a decimal unsigned integer.
338aa8b0 911
d62b8c6a
JH
912Returns the unsigned integer, if a valid value can be parsed
913from the beginning of the string.
f4379102 914
d62b8c6a 915Accepts only the decimal digits '0'..'9'.
6313e544 916
d62b8c6a
JH
917As opposed to atoi or strtol, grok_atou does NOT allow optional
918leading whitespace, or negative inputs. If such features are
919required, the calling code needs to explicitly implement those.
6313e544 920
d62b8c6a 921If a valid value cannot be parsed, returns either zero (if non-digits
75feedba 922are met before any digits) or UV_MAX (if the value overflows).
6313e544 923
d62b8c6a
JH
924Note that extraneous leading zeros also count as an overflow
925(meaning that only "0" is the zero).
338aa8b0 926
d62b8c6a 927On failure, the *endptr is also set to NULL, unless endptr is NULL.
338aa8b0
JH
928
929Trailing non-digit bytes are allowed if the endptr is non-NULL.
6313e544
JH
930On return the *endptr will contain the pointer to the first non-digit byte.
931
6313e544 932If the endptr is NULL, the first non-digit byte MUST be
f4379102 933the zero byte terminating the pv, or zero will be returned.
6313e544 934
d62b8c6a
JH
935Background: atoi has severe problems with illegal inputs, it cannot be
936used for incremental parsing, and therefore should be avoided
937atoi and strtol are also affected by locale settings, which can also be
938seen as a bug (global state controlled by user environment).
939
6313e544
JH
940=cut
941*/
942
75feedba 943UV
6313e544
JH
944Perl_grok_atou(const char *pv, const char** endptr)
945{
946 const char* s = pv;
947 const char** eptr;
948 const char* end2; /* Used in case endptr is NULL. */
75feedba 949 UV val = 0; /* The return value. */
6313e544
JH
950
951 PERL_ARGS_ASSERT_GROK_ATOU;
952
953 eptr = endptr ? endptr : &end2;
75feedba
JH
954 if (isDIGIT(*s)) {
955 /* Single-digit inputs are quite common. */
6313e544 956 val = *s++ - '0';
75feedba
JH
957 if (isDIGIT(*s)) {
958 /* Extra leading zeros cause overflow. */
959 if (val == 0) {
960 *eptr = NULL;
961 return UV_MAX;
962 }
963 while (isDIGIT(*s)) {
964 /* This could be unrolled like in grok_number(), but
965 * the expected uses of this are not speed-needy, and
966 * unlikely to need full 64-bitness. */
967 U8 digit = *s++ - '0';
945b524a
JH
968 if (val < uv_max_div_10 ||
969 (val == uv_max_div_10 && digit <= uv_max_mod_10)) {
75feedba
JH
970 val = val * 10 + digit;
971 } else {
6313e544 972 *eptr = NULL;
75feedba 973 return UV_MAX;
6313e544 974 }
6313e544
JH
975 }
976 }
75feedba
JH
977 }
978 if (s == pv) {
979 *eptr = NULL; /* If no progress, failed to parse anything. */
980 return 0;
6313e544
JH
981 }
982 if (endptr == NULL && *s) {
983 return 0; /* If endptr is NULL, no trailing non-digits allowed. */
984 }
985 *eptr = s;
986 return val;
987}
988
4801ca72 989STATIC NV
98994639
HS
990S_mulexp10(NV value, I32 exponent)
991{
992 NV result = 1.0;
993 NV power = 10.0;
994 bool negative = 0;
995 I32 bit;
996
997 if (exponent == 0)
998 return value;
659c4b96
DM
999 if (value == 0)
1000 return (NV)0;
87032ba1 1001
24866caa 1002 /* On OpenVMS VAX we by default use the D_FLOAT double format,
67597c89 1003 * and that format does not have *easy* capabilities [1] for
24866caa
CB
1004 * overflowing doubles 'silently' as IEEE fp does. We also need
1005 * to support G_FLOAT on both VAX and Alpha, and though the exponent
1006 * range is much larger than D_FLOAT it still doesn't do silent
1007 * overflow. Therefore we need to detect early whether we would
1008 * overflow (this is the behaviour of the native string-to-float
1009 * conversion routines, and therefore of native applications, too).
67597c89 1010 *
24866caa
CB
1011 * [1] Trying to establish a condition handler to trap floating point
1012 * exceptions is not a good idea. */
87032ba1
JH
1013
1014 /* In UNICOS and in certain Cray models (such as T90) there is no
1015 * IEEE fp, and no way at all from C to catch fp overflows gracefully.
1016 * There is something you can do if you are willing to use some
1017 * inline assembler: the instruction is called DFI-- but that will
1018 * disable *all* floating point interrupts, a little bit too large
1019 * a hammer. Therefore we need to catch potential overflows before
1020 * it's too late. */
353813d9 1021
85bba25f 1022#if ((defined(VMS) && !defined(_IEEE_FP)) || defined(_UNICOS)) && defined(NV_MAX_10_EXP)
353813d9 1023 STMT_START {
c4420975 1024 const NV exp_v = log10(value);
353813d9
HS
1025 if (exponent >= NV_MAX_10_EXP || exponent + exp_v >= NV_MAX_10_EXP)
1026 return NV_MAX;
1027 if (exponent < 0) {
1028 if (-(exponent + exp_v) >= NV_MAX_10_EXP)
1029 return 0.0;
1030 while (-exponent >= NV_MAX_10_EXP) {
1031 /* combination does not overflow, but 10^(-exponent) does */
1032 value /= 10;
1033 ++exponent;
1034 }
1035 }
1036 } STMT_END;
87032ba1
JH
1037#endif
1038
353813d9
HS
1039 if (exponent < 0) {
1040 negative = 1;
1041 exponent = -exponent;
b27804d8
DM
1042#ifdef NV_MAX_10_EXP
1043 /* for something like 1234 x 10^-309, the action of calculating
1044 * the intermediate value 10^309 then returning 1234 / (10^309)
1045 * will fail, since 10^309 becomes infinity. In this case try to
1046 * refactor it as 123 / (10^308) etc.
1047 */
1048 while (value && exponent > NV_MAX_10_EXP) {
1049 exponent--;
1050 value /= 10;
1051 }
1052#endif
353813d9 1053 }
98994639
HS
1054 for (bit = 1; exponent; bit <<= 1) {
1055 if (exponent & bit) {
1056 exponent ^= bit;
1057 result *= power;
236f0012
CB
1058 /* Floating point exceptions are supposed to be turned off,
1059 * but if we're obviously done, don't risk another iteration.
1060 */
1061 if (exponent == 0) break;
98994639
HS
1062 }
1063 power *= power;
1064 }
1065 return negative ? value / result : value * result;
1066}
1067
1068NV
1069Perl_my_atof(pTHX_ const char* s)
1070{
1071 NV x = 0.0;
1072#ifdef USE_LOCALE_NUMERIC
7918f24d
NC
1073 PERL_ARGS_ASSERT_MY_ATOF;
1074
a2287a13
KW
1075 {
1076 DECLARE_STORE_LC_NUMERIC_SET_TO_NEEDED();
d6ded950 1077 if (PL_numeric_radix_sv && IN_LC(LC_NUMERIC)) {
e4850248
KW
1078 const char *standard = NULL, *local = NULL;
1079 bool use_standard_radix;
98994639 1080
e4850248
KW
1081 /* Look through the string for the first thing that looks like a
1082 * decimal point: either the value in the current locale or the
1083 * standard fallback of '.'. The one which appears earliest in the
1084 * input string is the one that we should have atof look for. Note
1085 * that we have to determine this beforehand because on some
1086 * systems, Perl_atof2 is just a wrapper around the system's atof.
1087 * */
1088 standard = strchr(s, '.');
1089 local = strstr(s, SvPV_nolen(PL_numeric_radix_sv));
78787052 1090
e4850248 1091 use_standard_radix = standard && (!local || standard < local);
78787052 1092
e4850248
KW
1093 if (use_standard_radix)
1094 SET_NUMERIC_STANDARD();
78787052 1095
e4850248 1096 Perl_atof2(s, x);
78787052 1097
e4850248
KW
1098 if (use_standard_radix)
1099 SET_NUMERIC_LOCAL();
1100 }
1101 else
1102 Perl_atof2(s, x);
a2287a13
KW
1103 RESTORE_LC_NUMERIC();
1104 }
98994639 1105#else
a36244b7 1106 Perl_atof2(s, x);
98994639
HS
1107#endif
1108 return x;
1109}
1110
1111char*
1112Perl_my_atof2(pTHX_ const char* orig, NV* value)
1113{
20f6aaab 1114 NV result[3] = {0.0, 0.0, 0.0};
e1ec3a88 1115 const char* s = orig;
a36244b7 1116#ifdef USE_PERL_ATOF
20f6aaab 1117 UV accumulator[2] = {0,0}; /* before/after dp */
a36244b7 1118 bool negative = 0;
ae776a2c 1119 const char* send = s + strlen(orig); /* one past the last */
8194bf88 1120 bool seen_digit = 0;
20f6aaab
AS
1121 I32 exp_adjust[2] = {0,0};
1122 I32 exp_acc[2] = {-1, -1};
1123 /* the current exponent adjust for the accumulators */
98994639 1124 I32 exponent = 0;
8194bf88 1125 I32 seen_dp = 0;
20f6aaab
AS
1126 I32 digit = 0;
1127 I32 old_digit = 0;
8194bf88
DM
1128 I32 sig_digits = 0; /* noof significant digits seen so far */
1129
7918f24d
NC
1130 PERL_ARGS_ASSERT_MY_ATOF2;
1131
8194bf88
DM
1132/* There is no point in processing more significant digits
1133 * than the NV can hold. Note that NV_DIG is a lower-bound value,
1134 * while we need an upper-bound value. We add 2 to account for this;
1135 * since it will have been conservative on both the first and last digit.
1136 * For example a 32-bit mantissa with an exponent of 4 would have
1137 * exact values in the set
1138 * 4
1139 * 8
1140 * ..
1141 * 17179869172
1142 * 17179869176
1143 * 17179869180
1144 *
1145 * where for the purposes of calculating NV_DIG we would have to discount
1146 * both the first and last digit, since neither can hold all values from
1147 * 0..9; but for calculating the value we must examine those two digits.
1148 */
ffa277e5
AS
1149#ifdef MAX_SIG_DIG_PLUS
1150 /* It is not necessarily the case that adding 2 to NV_DIG gets all the
1151 possible digits in a NV, especially if NVs are not IEEE compliant
1152 (e.g., long doubles on IRIX) - Allen <allens@cpan.org> */
1153# define MAX_SIG_DIGITS (NV_DIG+MAX_SIG_DIG_PLUS)
1154#else
1155# define MAX_SIG_DIGITS (NV_DIG+2)
1156#endif
8194bf88
DM
1157
1158/* the max number we can accumulate in a UV, and still safely do 10*N+9 */
1159#define MAX_ACCUMULATE ( (UV) ((UV_MAX - 9)/10))
98994639 1160
96a05aee
HS
1161 /* leading whitespace */
1162 while (isSPACE(*s))
1163 ++s;
1164
98994639
HS
1165 /* sign */
1166 switch (*s) {
1167 case '-':
1168 negative = 1;
924ba076 1169 /* FALLTHROUGH */
98994639
HS
1170 case '+':
1171 ++s;
1172 }
1173
ae776a2c
JH
1174 {
1175 const char *p0 = negative ? s - 1 : s;
1176 const char *p = p0;
1177#if defined(NV_INF) && defined(NV_NAN)
1178 int infnan_flags = grok_infnan(&p, send);
1179 if (infnan_flags && p != p0) {
1180 if ((infnan_flags & IS_NUMBER_INFINITY)) {
1181 *value = (infnan_flags & IS_NUMBER_NEG) ? -NV_INF: NV_INF;
1182 return (char*)p;
1183 }
1184 else if ((infnan_flags & IS_NUMBER_NAN)) {
1185 *value = NV_NAN;
1186 return (char*)p;
1187 }
1188 }
1189#elif defined(HAS_STRTOD)
9ff909cf 1190 if (INFNAN_PEEK(s, send)) {
ae776a2c 1191 /* The native strtod() may not get all the possible
9ff909cf 1192 * inf/nan strings INFNAN_PEEK() recognizes. */
ae776a2c 1193 char* endp;
f1b32d61 1194 NV nv = Perl_strtod(p, &endp);
ae776a2c
JH
1195 if (p != endp) {
1196 *value = nv;
1197 return endp;
1198 }
2b54f59f 1199 }
2b54f59f 1200#endif
ae776a2c 1201 }
2b54f59f 1202
8194bf88
DM
1203 /* we accumulate digits into an integer; when this becomes too
1204 * large, we add the total to NV and start again */
98994639 1205
8194bf88
DM
1206 while (1) {
1207 if (isDIGIT(*s)) {
1208 seen_digit = 1;
20f6aaab 1209 old_digit = digit;
8194bf88 1210 digit = *s++ - '0';
20f6aaab
AS
1211 if (seen_dp)
1212 exp_adjust[1]++;
98994639 1213
8194bf88
DM
1214 /* don't start counting until we see the first significant
1215 * digit, eg the 5 in 0.00005... */
1216 if (!sig_digits && digit == 0)
1217 continue;
1218
1219 if (++sig_digits > MAX_SIG_DIGITS) {
98994639 1220 /* limits of precision reached */
20f6aaab
AS
1221 if (digit > 5) {
1222 ++accumulator[seen_dp];
1223 } else if (digit == 5) {
1224 if (old_digit % 2) { /* round to even - Allen */
1225 ++accumulator[seen_dp];
1226 }
1227 }
1228 if (seen_dp) {
1229 exp_adjust[1]--;
1230 } else {
1231 exp_adjust[0]++;
1232 }
8194bf88 1233 /* skip remaining digits */
98994639 1234 while (isDIGIT(*s)) {
98994639 1235 ++s;
20f6aaab
AS
1236 if (! seen_dp) {
1237 exp_adjust[0]++;
1238 }
98994639
HS
1239 }
1240 /* warn of loss of precision? */
98994639 1241 }
8194bf88 1242 else {
20f6aaab 1243 if (accumulator[seen_dp] > MAX_ACCUMULATE) {
8194bf88 1244 /* add accumulator to result and start again */
20f6aaab
AS
1245 result[seen_dp] = S_mulexp10(result[seen_dp],
1246 exp_acc[seen_dp])
1247 + (NV)accumulator[seen_dp];
1248 accumulator[seen_dp] = 0;
1249 exp_acc[seen_dp] = 0;
98994639 1250 }
20f6aaab
AS
1251 accumulator[seen_dp] = accumulator[seen_dp] * 10 + digit;
1252 ++exp_acc[seen_dp];
98994639 1253 }
8194bf88 1254 }
e1ec3a88 1255 else if (!seen_dp && GROK_NUMERIC_RADIX(&s, send)) {
8194bf88 1256 seen_dp = 1;
20f6aaab 1257 if (sig_digits > MAX_SIG_DIGITS) {
c86f7df5 1258 do {
20f6aaab 1259 ++s;
c86f7df5 1260 } while (isDIGIT(*s));
20f6aaab
AS
1261 break;
1262 }
8194bf88
DM
1263 }
1264 else {
1265 break;
98994639
HS
1266 }
1267 }
1268
20f6aaab
AS
1269 result[0] = S_mulexp10(result[0], exp_acc[0]) + (NV)accumulator[0];
1270 if (seen_dp) {
1271 result[1] = S_mulexp10(result[1], exp_acc[1]) + (NV)accumulator[1];
1272 }
98994639 1273
305b8651 1274 if (seen_digit && (isALPHA_FOLD_EQ(*s, 'e'))) {
98994639
HS
1275 bool expnegative = 0;
1276
1277 ++s;
1278 switch (*s) {
1279 case '-':
1280 expnegative = 1;
924ba076 1281 /* FALLTHROUGH */
98994639
HS
1282 case '+':
1283 ++s;
1284 }
1285 while (isDIGIT(*s))
1286 exponent = exponent * 10 + (*s++ - '0');
1287 if (expnegative)
1288 exponent = -exponent;
1289 }
1290
20f6aaab
AS
1291
1292
98994639 1293 /* now apply the exponent */
20f6aaab
AS
1294
1295 if (seen_dp) {
1296 result[2] = S_mulexp10(result[0],exponent+exp_adjust[0])
1297 + S_mulexp10(result[1],exponent-exp_adjust[1]);
1298 } else {
1299 result[2] = S_mulexp10(result[0],exponent+exp_adjust[0]);
1300 }
98994639
HS
1301
1302 /* now apply the sign */
1303 if (negative)
20f6aaab 1304 result[2] = -result[2];
a36244b7 1305#endif /* USE_PERL_ATOF */
20f6aaab 1306 *value = result[2];
73d840c0 1307 return (char *)s;
98994639
HS
1308}
1309
55954f19
JH
1310#if ! defined(HAS_MODFL) && defined(HAS_AINTL) && defined(HAS_COPYSIGNL)
1311long double
1312Perl_my_modfl(long double x, long double *ip)
1313{
1314 *ip = aintl(x);
1315 return (x == *ip ? copysignl(0.0L, x) : x - *ip);
1316}
1317#endif
1318
1319#if ! defined(HAS_FREXPL) && defined(HAS_ILOGBL) && defined(HAS_SCALBNL)
1320long double
1321Perl_my_frexpl(long double x, int *e) {
1322 *e = x == 0.0L ? 0 : ilogbl(x) + 1;
1323 return (scalbnl(x, -*e));
1324}
1325#endif
66610fdd
RGS
1326
1327/*
ed140128
AD
1328=for apidoc Perl_signbit
1329
1330Return a non-zero integer if the sign bit on an NV is set, and 0 if
1331it is not.
1332
1333If Configure detects this system has a signbit() that will work with
1334our NVs, then we just use it via the #define in perl.h. Otherwise,
8b7fad81
JH
1335fall back on this implementation. The main use of this function
1336is catching -0.0.
ed140128
AD
1337
1338Configure notes: This function is called 'Perl_signbit' instead of a
1339plain 'signbit' because it is easy to imagine a system having a signbit()
1340function or macro that doesn't happen to work with our particular choice
1341of NVs. We shouldn't just re-#define signbit as Perl_signbit and expect
1342the standard system headers to be happy. Also, this is a no-context
1343function (no pTHX_) because Perl_signbit() is usually re-#defined in
1344perl.h as a simple macro call to the system's signbit().
1345Users should just always call Perl_signbit().
1346
1347=cut
1348*/
1349#if !defined(HAS_SIGNBIT)
1350int
1351Perl_signbit(NV x) {
8b7fad81
JH
1352# ifdef Perl_fp_class_nzero
1353 if (x == 0)
1354 return Perl_fp_class_nzero(x);
8b7fad81 1355# endif
3585840c 1356 return (x < 0.0) ? 1 : 0;
ed140128
AD
1357}
1358#endif
1359
1360/*
66610fdd
RGS
1361 * Local variables:
1362 * c-indentation-style: bsd
1363 * c-basic-offset: 4
14d04a33 1364 * indent-tabs-mode: nil
66610fdd
RGS
1365 * End:
1366 *
14d04a33 1367 * ex: set ts=8 sts=4 sw=4 et:
37442d52 1368 */