source: vendor/current/source3/modules/getdate.y@ 596

Last change on this file since 596 was 414, checked in by Herwig Bauernfeind, 16 years ago

Samba 3.5.0: Initial import
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[414]1%{
2/* Parse a string into an internal time stamp.
3 Copyright (C) 1999, 2000, 2002 Free Software Foundation, Inc.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
8 any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, see <http://www.gnu.org/licenses/>. */
17
18/* Originally written by Steven M. Bellovin <[email protected]> while
19 at the University of North Carolina at Chapel Hill. Later tweaked by
20 a couple of people on Usenet. Completely overhauled by Rich $alz
21 <[email protected]> and Jim Berets <[email protected]> in August, 1990.
22
23 Modified by Paul Eggert <[email protected]> in August 1999 to do
24 the right thing about local DST. Unlike previous versions, this
25 version is reentrant. */
26
27#ifdef HAVE_CONFIG_H
28# include <config.h>
29# ifdef HAVE_ALLOCA_H
30# include <alloca.h>
31# endif
32#endif
33
34/* Since the code of getdate.y is not included in the Emacs executable
35 itself, there is no need to #define static in this file. Even if
36 the code were included in the Emacs executable, it probably
37 wouldn't do any harm to #undef it here; this will only cause
38 problems if we try to write to a static variable, which I don't
39 think this code needs to do. */
40#ifdef emacs
41# undef static
42#endif
43
44#include <ctype.h>
45#include <string.h>
46
47#if HAVE_STDLIB_H
48# include <stdlib.h> /* for `free'; used by Bison 1.27 */
49#endif
50
51#if STDC_HEADERS || (! defined isascii && ! HAVE_ISASCII)
52# define IN_CTYPE_DOMAIN(c) 1
53#else
54# define IN_CTYPE_DOMAIN(c) isascii (c)
55#endif
56
57#define ISSPACE(c) (IN_CTYPE_DOMAIN (c) && isspace (c))
58#define ISALPHA(c) (IN_CTYPE_DOMAIN (c) && isalpha (c))
59#define ISLOWER(c) (IN_CTYPE_DOMAIN (c) && islower (c))
60#define ISDIGIT_LOCALE(c) (IN_CTYPE_DOMAIN (c) && isdigit (c))
61
62/* ISDIGIT differs from ISDIGIT_LOCALE, as follows:
63 - Its arg may be any int or unsigned int; it need not be an unsigned char.
64 - It's guaranteed to evaluate its argument exactly once.
65 - It's typically faster.
66 POSIX says that only '0' through '9' are digits. Prefer ISDIGIT to
67 ISDIGIT_LOCALE unless it's important to use the locale's definition
68 of `digit' even when the host does not conform to POSIX. */
69#define ISDIGIT(c) ((unsigned) (c) - '0' <= 9)
70
71#if STDC_HEADERS || HAVE_STRING_H
72# include <string.h>
73#endif
74
75#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
76# define __attribute__(x)
77#endif
78
79#ifndef ATTRIBUTE_UNUSED
80# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
81#endif
82
83#define EPOCH_YEAR 1970
84#define TM_YEAR_BASE 1900
85
86#define HOUR(x) ((x) * 60)
87
88/* An integer value, and the number of digits in its textual
89 representation. */
90typedef struct
91{
92 int value;
93 int digits;
94} textint;
95
96/* An entry in the lexical lookup table. */
97typedef struct
98{
99 char const *name;
100 int type;
101 int value;
102} table;
103
104/* Meridian: am, pm, or 24-hour style. */
105enum { MERam, MERpm, MER24 };
106
107/* Information passed to and from the parser. */
108typedef struct
109{
110 /* The input string remaining to be parsed. */
111 const char *input;
112
113 /* N, if this is the Nth Tuesday. */
114 int day_ordinal;
115
116 /* Day of week; Sunday is 0. */
117 int day_number;
118
119 /* tm_isdst flag for the local zone. */
120 int local_isdst;
121
122 /* Time zone, in minutes east of UTC. */
123 int time_zone;
124
125 /* Style used for time. */
126 int meridian;
127
128 /* Gregorian year, month, day, hour, minutes, and seconds. */
129 textint year;
130 int month;
131 int day;
132 int hour;
133 int minutes;
134 int seconds;
135
136 /* Relative year, month, day, hour, minutes, and seconds. */
137 int rel_year;
138 int rel_month;
139 int rel_day;
140 int rel_hour;
141 int rel_minutes;
142 int rel_seconds;
143
144 /* Counts of nonterminals of various flavors parsed so far. */
145 int dates_seen;
146 int days_seen;
147 int local_zones_seen;
148 int rels_seen;
149 int times_seen;
150 int zones_seen;
151
152 /* Table of local time zone abbrevations, terminated by a null entry. */
153 table local_time_zone_table[3];
154} parser_control;
155
156#define PC (* (parser_control *) parm)
157#define YYLEX_PARAM parm
158#define YYPARSE_PARAM parm
159
160%}
161
162/* We want a reentrant parser. */
163%pure_parser
164
165/* This grammar has 13 shift/reduce conflicts. */
166%expect 13
167
168%union
169{
170 int intval;
171 textint textintval;
172}
173
174%{
175
176static int yyerror(const char *);
177static int yylex(YYSTYPE *, parser_control *);
178
179%}
180
181%token tAGO tDST
182
183%token <intval> tDAY tDAY_UNIT tDAYZONE tHOUR_UNIT tLOCAL_ZONE tMERIDIAN
184%token <intval> tMINUTE_UNIT tMONTH tMONTH_UNIT tSEC_UNIT tYEAR_UNIT tZONE
185
186%token <textintval> tSNUMBER tUNUMBER
187
188%type <intval> o_merid
189
190%%
191
192spec:
193 /* empty */
194 | spec item
195 ;
196
197item:
198 time
199 { PC.times_seen++; }
200 | local_zone
201 { PC.local_zones_seen++; }
202 | zone
203 { PC.zones_seen++; }
204 | date
205 { PC.dates_seen++; }
206 | day
207 { PC.days_seen++; }
208 | rel
209 { PC.rels_seen++; }
210 | number
211 ;
212
213time:
214 tUNUMBER tMERIDIAN
215 {
216 PC.hour = $1.value;
217 PC.minutes = 0;
218 PC.seconds = 0;
219 PC.meridian = $2;
220 }
221 | tUNUMBER ':' tUNUMBER o_merid
222 {
223 PC.hour = $1.value;
224 PC.minutes = $3.value;
225 PC.seconds = 0;
226 PC.meridian = $4;
227 }
228 | tUNUMBER ':' tUNUMBER tSNUMBER
229 {
230 PC.hour = $1.value;
231 PC.minutes = $3.value;
232 PC.meridian = MER24;
233 PC.zones_seen++;
234 PC.time_zone = $4.value % 100 + ($4.value / 100) * 60;
235 }
236 | tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid
237 {
238 PC.hour = $1.value;
239 PC.minutes = $3.value;
240 PC.seconds = $5.value;
241 PC.meridian = $6;
242 }
243 | tUNUMBER ':' tUNUMBER ':' tUNUMBER tSNUMBER
244 {
245 PC.hour = $1.value;
246 PC.minutes = $3.value;
247 PC.seconds = $5.value;
248 PC.meridian = MER24;
249 PC.zones_seen++;
250 PC.time_zone = $6.value % 100 + ($6.value / 100) * 60;
251 }
252 ;
253
254local_zone:
255 tLOCAL_ZONE
256 { PC.local_isdst = $1; }
257 | tLOCAL_ZONE tDST
258 { PC.local_isdst = $1 < 0 ? 1 : $1 + 1; }
259 ;
260
261zone:
262 tZONE
263 { PC.time_zone = $1; }
264 | tDAYZONE
265 { PC.time_zone = $1 + 60; }
266 | tZONE tDST
267 { PC.time_zone = $1 + 60; }
268 ;
269
270day:
271 tDAY
272 {
273 PC.day_ordinal = 1;
274 PC.day_number = $1;
275 }
276 | tDAY ','
277 {
278 PC.day_ordinal = 1;
279 PC.day_number = $1;
280 }
281 | tUNUMBER tDAY
282 {
283 PC.day_ordinal = $1.value;
284 PC.day_number = $2;
285 }
286 ;
287
288date:
289 tUNUMBER '/' tUNUMBER
290 {
291 PC.month = $1.value;
292 PC.day = $3.value;
293 }
294 | tUNUMBER '/' tUNUMBER '/' tUNUMBER
295 {
296 /* Interpret as YYYY/MM/DD if the first value has 4 or more digits,
297 otherwise as MM/DD/YY.
298 The goal in recognizing YYYY/MM/DD is solely to support legacy
299 machine-generated dates like those in an RCS log listing. If
300 you want portability, use the ISO 8601 format. */
301 if (4 <= $1.digits)
302 {
303 PC.year = $1;
304 PC.month = $3.value;
305 PC.day = $5.value;
306 }
307 else
308 {
309 PC.month = $1.value;
310 PC.day = $3.value;
311 PC.year = $5;
312 }
313 }
314 | tUNUMBER tSNUMBER tSNUMBER
315 {
316 /* ISO 8601 format. YYYY-MM-DD. */
317 PC.year = $1;
318 PC.month = -$2.value;
319 PC.day = -$3.value;
320 }
321 | tUNUMBER tMONTH tSNUMBER
322 {
323 /* e.g. 17-JUN-1992. */
324 PC.day = $1.value;
325 PC.month = $2;
326 PC.year.value = -$3.value;
327 PC.year.digits = $3.digits;
328 }
329 | tMONTH tUNUMBER
330 {
331 PC.month = $1;
332 PC.day = $2.value;
333 }
334 | tMONTH tUNUMBER ',' tUNUMBER
335 {
336 PC.month = $1;
337 PC.day = $2.value;
338 PC.year = $4;
339 }
340 | tUNUMBER tMONTH
341 {
342 PC.day = $1.value;
343 PC.month = $2;
344 }
345 | tUNUMBER tMONTH tUNUMBER
346 {
347 PC.day = $1.value;
348 PC.month = $2;
349 PC.year = $3;
350 }
351 ;
352
353rel:
354 relunit tAGO
355 {
356 PC.rel_seconds = -PC.rel_seconds;
357 PC.rel_minutes = -PC.rel_minutes;
358 PC.rel_hour = -PC.rel_hour;
359 PC.rel_day = -PC.rel_day;
360 PC.rel_month = -PC.rel_month;
361 PC.rel_year = -PC.rel_year;
362 }
363 | relunit
364 ;
365
366relunit:
367 tUNUMBER tYEAR_UNIT
368 { PC.rel_year += $1.value * $2; }
369 | tSNUMBER tYEAR_UNIT
370 { PC.rel_year += $1.value * $2; }
371 | tYEAR_UNIT
372 { PC.rel_year += $1; }
373 | tUNUMBER tMONTH_UNIT
374 { PC.rel_month += $1.value * $2; }
375 | tSNUMBER tMONTH_UNIT
376 { PC.rel_month += $1.value * $2; }
377 | tMONTH_UNIT
378 { PC.rel_month += $1; }
379 | tUNUMBER tDAY_UNIT
380 { PC.rel_day += $1.value * $2; }
381 | tSNUMBER tDAY_UNIT
382 { PC.rel_day += $1.value * $2; }
383 | tDAY_UNIT
384 { PC.rel_day += $1; }
385 | tUNUMBER tHOUR_UNIT
386 { PC.rel_hour += $1.value * $2; }
387 | tSNUMBER tHOUR_UNIT
388 { PC.rel_hour += $1.value * $2; }
389 | tHOUR_UNIT
390 { PC.rel_hour += $1; }
391 | tUNUMBER tMINUTE_UNIT
392 { PC.rel_minutes += $1.value * $2; }
393 | tSNUMBER tMINUTE_UNIT
394 { PC.rel_minutes += $1.value * $2; }
395 | tMINUTE_UNIT
396 { PC.rel_minutes += $1; }
397 | tUNUMBER tSEC_UNIT
398 { PC.rel_seconds += $1.value * $2; }
399 | tSNUMBER tSEC_UNIT
400 { PC.rel_seconds += $1.value * $2; }
401 | tSEC_UNIT
402 { PC.rel_seconds += $1; }
403 ;
404
405number:
406 tUNUMBER
407 {
408 if (PC.dates_seen
409 && ! PC.rels_seen && (PC.times_seen || 2 < $1.digits))
410 PC.year = $1;
411 else
412 {
413 if (4 < $1.digits)
414 {
415 PC.dates_seen++;
416 PC.day = $1.value % 100;
417 PC.month = ($1.value / 100) % 100;
418 PC.year.value = $1.value / 10000;
419 PC.year.digits = $1.digits - 4;
420 }
421 else
422 {
423 PC.times_seen++;
424 if ($1.digits <= 2)
425 {
426 PC.hour = $1.value;
427 PC.minutes = 0;
428 }
429 else
430 {
431 PC.hour = $1.value / 100;
432 PC.minutes = $1.value % 100;
433 }
434 PC.seconds = 0;
435 PC.meridian = MER24;
436 }
437 }
438 }
439 ;
440
441o_merid:
442 /* empty */
443 { $$ = MER24; }
444 | tMERIDIAN
445 { $$ = $1; }
446 ;
447
448%%
449
450/* Include this file down here because bison inserts code above which
451 may define-away `const'. We want the prototype for get_date to have
452 the same signature as the function definition. */
453#include "modules/getdate.h"
454
455#ifndef gmtime
456struct tm *gmtime (const time_t *);
457#endif
458#ifndef localtime
459struct tm *localtime (const time_t *);
460#endif
461#ifndef mktime
462time_t mktime (struct tm *);
463#endif
464
465static table const meridian_table[] =
466{
467 { "AM", tMERIDIAN, MERam },
468 { "A.M.", tMERIDIAN, MERam },
469 { "PM", tMERIDIAN, MERpm },
470 { "P.M.", tMERIDIAN, MERpm },
471 { 0, 0, 0 }
472};
473
474static table const dst_table[] =
475{
476 { "DST", tDST, 0 }
477};
478
479static table const month_and_day_table[] =
480{
481 { "JANUARY", tMONTH, 1 },
482 { "FEBRUARY", tMONTH, 2 },
483 { "MARCH", tMONTH, 3 },
484 { "APRIL", tMONTH, 4 },
485 { "MAY", tMONTH, 5 },
486 { "JUNE", tMONTH, 6 },
487 { "JULY", tMONTH, 7 },
488 { "AUGUST", tMONTH, 8 },
489 { "SEPTEMBER",tMONTH, 9 },
490 { "SEPT", tMONTH, 9 },
491 { "OCTOBER", tMONTH, 10 },
492 { "NOVEMBER", tMONTH, 11 },
493 { "DECEMBER", tMONTH, 12 },
494 { "SUNDAY", tDAY, 0 },
495 { "MONDAY", tDAY, 1 },
496 { "TUESDAY", tDAY, 2 },
497 { "TUES", tDAY, 2 },
498 { "WEDNESDAY",tDAY, 3 },
499 { "WEDNES", tDAY, 3 },
500 { "THURSDAY", tDAY, 4 },
501 { "THUR", tDAY, 4 },
502 { "THURS", tDAY, 4 },
503 { "FRIDAY", tDAY, 5 },
504 { "SATURDAY", tDAY, 6 },
505 { 0, 0, 0 }
506};
507
508static table const time_units_table[] =
509{
510 { "YEAR", tYEAR_UNIT, 1 },
511 { "MONTH", tMONTH_UNIT, 1 },
512 { "FORTNIGHT",tDAY_UNIT, 14 },
513 { "WEEK", tDAY_UNIT, 7 },
514 { "DAY", tDAY_UNIT, 1 },
515 { "HOUR", tHOUR_UNIT, 1 },
516 { "MINUTE", tMINUTE_UNIT, 1 },
517 { "MIN", tMINUTE_UNIT, 1 },
518 { "SECOND", tSEC_UNIT, 1 },
519 { "SEC", tSEC_UNIT, 1 },
520 { 0, 0, 0 }
521};
522
523/* Assorted relative-time words. */
524static table const relative_time_table[] =
525{
526 { "TOMORROW", tMINUTE_UNIT, 24 * 60 },
527 { "YESTERDAY",tMINUTE_UNIT, - (24 * 60) },
528 { "TODAY", tMINUTE_UNIT, 0 },
529 { "NOW", tMINUTE_UNIT, 0 },
530 { "LAST", tUNUMBER, -1 },
531 { "THIS", tUNUMBER, 0 },
532 { "NEXT", tUNUMBER, 1 },
533 { "FIRST", tUNUMBER, 1 },
534/*{ "SECOND", tUNUMBER, 2 }, */
535 { "THIRD", tUNUMBER, 3 },
536 { "FOURTH", tUNUMBER, 4 },
537 { "FIFTH", tUNUMBER, 5 },
538 { "SIXTH", tUNUMBER, 6 },
539 { "SEVENTH", tUNUMBER, 7 },
540 { "EIGHTH", tUNUMBER, 8 },
541 { "NINTH", tUNUMBER, 9 },
542 { "TENTH", tUNUMBER, 10 },
543 { "ELEVENTH", tUNUMBER, 11 },
544 { "TWELFTH", tUNUMBER, 12 },
545 { "AGO", tAGO, 1 },
546 { 0, 0, 0 }
547};
548
549/* The time zone table. This table is necessarily incomplete, as time
550 zone abbreviations are ambiguous; e.g. Australians interpret "EST"
551 as Eastern time in Australia, not as US Eastern Standard Time.
552 You cannot rely on getdate to handle arbitrary time zone
553 abbreviations; use numeric abbreviations like `-0500' instead. */
554static table const time_zone_table[] =
555{
556 { "GMT", tZONE, HOUR ( 0) }, /* Greenwich Mean */
557 { "UT", tZONE, HOUR ( 0) }, /* Universal (Coordinated) */
558 { "UTC", tZONE, HOUR ( 0) },
559 { "WET", tZONE, HOUR ( 0) }, /* Western European */
560 { "WEST", tDAYZONE, HOUR ( 0) }, /* Western European Summer */
561 { "BST", tDAYZONE, HOUR ( 0) }, /* British Summer */
562 { "ART", tZONE, -HOUR ( 3) }, /* Argentina */
563 { "BRT", tZONE, -HOUR ( 3) }, /* Brazil */
564 { "BRST", tDAYZONE, -HOUR ( 3) }, /* Brazil Summer */
565 { "NST", tZONE, -(HOUR ( 3) + 30) }, /* Newfoundland Standard */
566 { "NDT", tDAYZONE,-(HOUR ( 3) + 30) }, /* Newfoundland Daylight */
567 { "AST", tZONE, -HOUR ( 4) }, /* Atlantic Standard */
568 { "ADT", tDAYZONE, -HOUR ( 4) }, /* Atlantic Daylight */
569 { "CLT", tZONE, -HOUR ( 4) }, /* Chile */
570 { "CLST", tDAYZONE, -HOUR ( 4) }, /* Chile Summer */
571 { "EST", tZONE, -HOUR ( 5) }, /* Eastern Standard */
572 { "EDT", tDAYZONE, -HOUR ( 5) }, /* Eastern Daylight */
573 { "CST", tZONE, -HOUR ( 6) }, /* Central Standard */
574 { "CDT", tDAYZONE, -HOUR ( 6) }, /* Central Daylight */
575 { "MST", tZONE, -HOUR ( 7) }, /* Mountain Standard */
576 { "MDT", tDAYZONE, -HOUR ( 7) }, /* Mountain Daylight */
577 { "PST", tZONE, -HOUR ( 8) }, /* Pacific Standard */
578 { "PDT", tDAYZONE, -HOUR ( 8) }, /* Pacific Daylight */
579 { "AKST", tZONE, -HOUR ( 9) }, /* Alaska Standard */
580 { "AKDT", tDAYZONE, -HOUR ( 9) }, /* Alaska Daylight */
581 { "HST", tZONE, -HOUR (10) }, /* Hawaii Standard */
582 { "HAST", tZONE, -HOUR (10) }, /* Hawaii-Aleutian Standard */
583 { "HADT", tDAYZONE, -HOUR (10) }, /* Hawaii-Aleutian Daylight */
584 { "SST", tZONE, -HOUR (12) }, /* Samoa Standard */
585 { "WAT", tZONE, HOUR ( 1) }, /* West Africa */
586 { "CET", tZONE, HOUR ( 1) }, /* Central European */
587 { "CEST", tDAYZONE, HOUR ( 1) }, /* Central European Summer */
588 { "MET", tZONE, HOUR ( 1) }, /* Middle European */
589 { "MEZ", tZONE, HOUR ( 1) }, /* Middle European */
590 { "MEST", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */
591 { "MESZ", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */
592 { "EET", tZONE, HOUR ( 2) }, /* Eastern European */
593 { "EEST", tDAYZONE, HOUR ( 2) }, /* Eastern European Summer */
594 { "CAT", tZONE, HOUR ( 2) }, /* Central Africa */
595 { "SAST", tZONE, HOUR ( 2) }, /* South Africa Standard */
596 { "EAT", tZONE, HOUR ( 3) }, /* East Africa */
597 { "MSK", tZONE, HOUR ( 3) }, /* Moscow */
598 { "MSD", tDAYZONE, HOUR ( 3) }, /* Moscow Daylight */
599 { "IST", tZONE, (HOUR ( 5) + 30) }, /* India Standard */
600 { "SGT", tZONE, HOUR ( 8) }, /* Singapore */
601 { "KST", tZONE, HOUR ( 9) }, /* Korea Standard */
602 { "JST", tZONE, HOUR ( 9) }, /* Japan Standard */
603 { "GST", tZONE, HOUR (10) }, /* Guam Standard */
604 { "NZST", tZONE, HOUR (12) }, /* New Zealand Standard */
605 { "NZDT", tDAYZONE, HOUR (12) }, /* New Zealand Daylight */
606 { 0, 0, 0 }
607};
608
609/* Military time zone table. */
610static table const military_table[] =
611{
612 { "A", tZONE, -HOUR ( 1) },
613 { "B", tZONE, -HOUR ( 2) },
614 { "C", tZONE, -HOUR ( 3) },
615 { "D", tZONE, -HOUR ( 4) },
616 { "E", tZONE, -HOUR ( 5) },
617 { "F", tZONE, -HOUR ( 6) },
618 { "G", tZONE, -HOUR ( 7) },
619 { "H", tZONE, -HOUR ( 8) },
620 { "I", tZONE, -HOUR ( 9) },
621 { "K", tZONE, -HOUR (10) },
622 { "L", tZONE, -HOUR (11) },
623 { "M", tZONE, -HOUR (12) },
624 { "N", tZONE, HOUR ( 1) },
625 { "O", tZONE, HOUR ( 2) },
626 { "P", tZONE, HOUR ( 3) },
627 { "Q", tZONE, HOUR ( 4) },
628 { "R", tZONE, HOUR ( 5) },
629 { "S", tZONE, HOUR ( 6) },
630 { "T", tZONE, HOUR ( 7) },
631 { "U", tZONE, HOUR ( 8) },
632 { "V", tZONE, HOUR ( 9) },
633 { "W", tZONE, HOUR (10) },
634 { "X", tZONE, HOUR (11) },
635 { "Y", tZONE, HOUR (12) },
636 { "Z", tZONE, HOUR ( 0) },
637 { 0, 0, 0 }
638};
639
640
641
642
643static int
644to_hour (int hours, int meridian)
645{
646 switch (meridian)
647 {
648 case MER24:
649 return 0 <= hours && hours < 24 ? hours : -1;
650 case MERam:
651 return 0 < hours && hours < 12 ? hours : hours == 12 ? 0 : -1;
652 case MERpm:
653 return 0 < hours && hours < 12 ? hours + 12 : hours == 12 ? 12 : -1;
654 default:
655 abort ();
656 }
657 /* NOTREACHED */
658 return 0;
659}
660
661static int
662to_year (textint textyear)
663{
664 int year = textyear.value;
665
666 if (year < 0)
667 year = -year;
668
669 /* XPG4 suggests that years 00-68 map to 2000-2068, and
670 years 69-99 map to 1969-1999. */
671 if (textyear.digits == 2)
672 year += year < 69 ? 2000 : 1900;