1 %{
2 /* $OpenBSD: date.y,v 1.27 2023/03/08 04:43:10 guenther Exp $ */
3
4 /*
5 ** Originally written by Steven M. Bellovin <smb@research.att.com> while
6 ** at the University of North Carolina at Chapel Hill. Later tweaked by
7 ** a couple of people on Usenet. Completely overhauled by Rich $alz
8 ** <rsalz@bbn.com> and Jim Berets <jberets@bbn.com> in August, 1990;
9 **
10 ** This grammar has 10 shift/reduce conflicts.
11 **
12 ** This code is in the public domain and has no copyright.
13 */
14 /* SUPPRESS 287 on yaccpar_sccsid *//* Unused static variable */
15 /* SUPPRESS 288 on yyerrlab *//* Label unused */
16
17 #include <ctype.h>
18 #include <string.h>
19 #include <time.h>
20
21 #include "cvs.h"
22
23 #define YEAR_EPOCH 1970
24 #define YEAR_TMORIGIN 1900
25 #define HOUR(x) ((time_t)(x) * 60)
26 #define SECSPERDAY (24L * 60L * 60L)
27
28
29 /* An entry in the lexical lookup table */
30 typedef struct _TABLE {
31 char *name;
32 int type;
33 time_t value;
34 } TABLE;
35
36
37 /* Daylight-savings mode: on, off, or not yet known. */
38 typedef enum _DSTMODE {
39 DSTon, DSToff, DSTmaybe
40 } DSTMODE;
41
42 /* Meridian: am, pm, or 24-hour style. */
43 typedef enum _MERIDIAN {
44 MERam, MERpm, MER24
45 } MERIDIAN;
46
47
48 /*
49 * Global variables. We could get rid of most of these by using a good
50 * union as the yacc stack. (This routine was originally written before
51 * yacc had the %union construct.) Maybe someday; right now we only use
52 * the %union very rarely.
53 */
54 static const char *yyInput;
55 static DSTMODE yyDSTmode;
56 static time_t yyDayOrdinal;
57 static time_t yyDayNumber;
58 static int yyHaveDate;
59 static int yyHaveDay;
60 static int yyHaveRel;
61 static int yyHaveTime;
62 static int yyHaveZone;
63 static time_t yyTimezone;
64 static time_t yyDay;
65 static time_t yyHour;
66 static time_t yyMinutes;
67 static time_t yyMonth;
68 static time_t yySeconds;
69 static time_t yyYear;
70 static MERIDIAN yyMeridian;
71 static time_t yyRelMonth;
72 static time_t yyRelSeconds;
73
74
75 static int yyerror(const char *);
76 static int yylex(void);
77 static int yyparse(void);
78 static int lookup(char *);
79
80 %}
81
82 %union {
83 time_t Number;
84 enum _MERIDIAN Meridian;
85 }
86
87 %token tAGO tDAY tDAYZONE tID tMERIDIAN tMINUTE_UNIT tMONTH tMONTH_UNIT
88 %token tSEC_UNIT tSNUMBER tUNUMBER tZONE tDST
89
90 %type <Number> tDAY tDAYZONE tMINUTE_UNIT tMONTH tMONTH_UNIT
91 %type <Number> tSEC_UNIT tSNUMBER tUNUMBER tZONE
92 %type <Meridian> tMERIDIAN o_merid
93
94 %%
95
96 spec : /* NULL */
97 | spec item
98 ;
99
100 item : time {
101 yyHaveTime++;
102 }
103 | zone {
104 yyHaveZone++;
105 }
106 | date {
107 yyHaveDate++;
108 }
109 | day {
110 yyHaveDay++;
111 }
112 | rel {
113 yyHaveRel++;
114 }
115 | number
116 ;
117
118 time : tUNUMBER tMERIDIAN {
119 yyHour = $1;
120 yyMinutes = 0;
121 yySeconds = 0;
122 yyMeridian = $2;
123 }
124 | tUNUMBER ':' tUNUMBER o_merid {
125 yyHour = $1;
126 yyMinutes = $3;
127 yySeconds = 0;
128 yyMeridian = $4;
129 }
130 | tUNUMBER ':' tUNUMBER tSNUMBER {
131 yyHour = $1;
132 yyMinutes = $3;
133 yyMeridian = MER24;
134 yyDSTmode = DSToff;
135 yyTimezone = - ($4 % 100 + ($4 / 100) * 60);
136 }
137 | tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid {
138 yyHour = $1;
139 yyMinutes = $3;
140 yySeconds = $5;
141 yyMeridian = $6;
142 }
143 | tUNUMBER ':' tUNUMBER ':' tUNUMBER tSNUMBER {
144 yyHour = $1;
145 yyMinutes = $3;
146 yySeconds = $5;
147 yyMeridian = MER24;
148 yyDSTmode = DSToff;
149 yyTimezone = - ($6 % 100 + ($6 / 100) * 60);
150 }
151 ;
152
153 zone : tZONE {
154 yyTimezone = $1;
155 yyDSTmode = DSToff;
156 }
157 | tDAYZONE {
158 yyTimezone = $1;
159 yyDSTmode = DSTon;
160 }
161 | tZONE tDST {
162 yyTimezone = $1;
163 yyDSTmode = DSTon;
164 }
165 ;
166
167 day : tDAY {
168 yyDayOrdinal = 1;
169 yyDayNumber = $1;
170 }
171 | tDAY ',' {
172 yyDayOrdinal = 1;
173 yyDayNumber = $1;
174 }
175 | tUNUMBER tDAY {
176 yyDayOrdinal = $1;
177 yyDayNumber = $2;
178 }
179 ;
180
181 date : tUNUMBER '/' tUNUMBER {
182 yyMonth = $1;
183 yyDay = $3;
184 }
185 | tUNUMBER '/' tUNUMBER '/' tUNUMBER {
186 if ($1 >= 100) {
187 yyYear = $1;
188 yyMonth = $3;
189 yyDay = $5;
190 } else {
191 yyMonth = $1;
192 yyDay = $3;
193 yyYear = $5;
194 }
195 }
196 | tUNUMBER tSNUMBER tSNUMBER {
197 /* ISO 8601 format. yyyy-mm-dd. */
198 yyYear = $1;
199 yyMonth = -$2;
200 yyDay = -$3;
201 }
202 | tUNUMBER tMONTH tSNUMBER {
203 /* e.g. 17-JUN-1992. */
204 yyDay = $1;
205 yyMonth = $2;
206 yyYear = -$3;
207 }
208 | tMONTH tUNUMBER {
209 yyMonth = $1;
210 yyDay = $2;
211 }
212 | tMONTH tUNUMBER ',' tUNUMBER {
213 yyMonth = $1;
214 yyDay = $2;
215 yyYear = $4;
216 }
217 | tUNUMBER tMONTH {
218 yyMonth = $2;
219 yyDay = $1;
220 }
221 | tUNUMBER tMONTH tUNUMBER {
222 yyMonth = $2;
223 yyDay = $1;
224 yyYear = $3;
225 }
226 ;
227
228 rel : relunit tAGO {
229 yyRelSeconds = -yyRelSeconds;
230 yyRelMonth = -yyRelMonth;
231 }
232 | relunit
233 ;
234
235 relunit : tUNUMBER tMINUTE_UNIT {
236 yyRelSeconds += $1 * $2 * 60L;
237 }
238 | tSNUMBER tMINUTE_UNIT {
239 yyRelSeconds += $1 * $2 * 60L;
240 }
241 | tMINUTE_UNIT {
242 yyRelSeconds += $1 * 60L;
243 }
244 | tSNUMBER tSEC_UNIT {
245 yyRelSeconds += $1;
246 }
247 | tUNUMBER tSEC_UNIT {
248 yyRelSeconds += $1;
249 }
250 | tSEC_UNIT {
251 yyRelSeconds++;
252 }
253 | tSNUMBER tMONTH_UNIT {
254 yyRelMonth += $1 * $2;
255 }
256 | tUNUMBER tMONTH_UNIT {
257 yyRelMonth += $1 * $2;
258 }
259 | tMONTH_UNIT {
260 yyRelMonth += $1;
261 }
262 ;
263
264 number : tUNUMBER {
265 if (yyHaveTime && yyHaveDate && !yyHaveRel)
266 yyYear = $1;
267 else {
268 if ($1 > 10000) {
269 yyHaveDate++;
270 yyDay= ($1)%100;
271 yyMonth= ($1/100)%100;
272 yyYear = $1/10000;
273 } else {
274 yyHaveTime++;
275 if ($1 < 100) {
276 yyHour = $1;
277 yyMinutes = 0;
278 } else {
279 yyHour = $1 / 100;
280 yyMinutes = $1 % 100;
281 }
282 yySeconds = 0;
283 yyMeridian = MER24;
284 }
285 }
286 }
287 ;
288
289 o_merid : /* NULL */ {
290 $$ = MER24;
291 }
292 | tMERIDIAN {
293 $$ = $1;
294 }
295 ;
296
297 %%
298
299 /* Month and day table. */
300 static TABLE const MonthDayTable[] = {
301 { "january", tMONTH, 1 },
302 { "february", tMONTH, 2 },
303 { "march", tMONTH, 3 },
304 { "april", tMONTH, 4 },
305 { "may", tMONTH, 5 },
306 { "june", tMONTH, 6 },
307 { "july", tMONTH, 7 },
308 { "august", tMONTH, 8 },
309 { "september", tMONTH, 9 },
310 { "sept", tMONTH, 9 },
311 { "october", tMONTH, 10 },
312 { "november", tMONTH, 11 },
313 { "december", tMONTH, 12 },
314 { "sunday", tDAY, 0 },
315 { "monday", tDAY, 1 },
316 { "tuesday", tDAY, 2 },
317 { "tues", tDAY, 2 },
318 { "wednesday", tDAY, 3 },
319 { "wednes", tDAY, 3 },
320 { "thursday", tDAY, 4 },
321 { "thur", tDAY, 4 },
322 { "thurs", tDAY, 4 },
323 { "friday", tDAY, 5 },
324 { "saturday", tDAY, 6 },
325 { NULL }
326 };
327
328 /* Time units table. */
329 static TABLE const UnitsTable[] = {
330 { "year", tMONTH_UNIT, 12 },
331 { "month", tMONTH_UNIT, 1 },
332 { "fortnight", tMINUTE_UNIT, 14 * 24 * 60 },
333 { "week", tMINUTE_UNIT, 7 * 24 * 60 },
334 { "day", tMINUTE_UNIT, 1 * 24 * 60 },
335 { "hour", tMINUTE_UNIT, 60 },
336 { "minute", tMINUTE_UNIT, 1 },
337 { "min", tMINUTE_UNIT, 1 },
338 { "second", tSEC_UNIT, 1 },
339 { "sec", tSEC_UNIT, 1 },
340 { NULL }
341 };
342
343 /* Assorted relative-time words. */
344 static TABLE const OtherTable[] = {
345 { "tomorrow", tMINUTE_UNIT, 1 * 24 * 60 },
346 { "yesterday", tMINUTE_UNIT, -1 * 24 * 60 },
347 { "today", tMINUTE_UNIT, 0 },
348 { "now", tMINUTE_UNIT, 0 },
349 { "last", tUNUMBER, -1 },
350 { "this", tMINUTE_UNIT, 0 },
351 { "next", tUNUMBER, 2 },
352 { "first", tUNUMBER, 1 },
353 /* { "second", tUNUMBER, 2 }, */
354 { "third", tUNUMBER, 3 },
355 { "fourth", tUNUMBER, 4 },
356 { "fifth", tUNUMBER, 5 },
357 { "sixth", tUNUMBER, 6 },
358 { "seventh", tUNUMBER, 7 },
359 { "eighth", tUNUMBER, 8 },
360 { "ninth", tUNUMBER, 9 },
361 { "tenth", tUNUMBER, 10 },
362 { "eleventh", tUNUMBER, 11 },
363 { "twelfth", tUNUMBER, 12 },
364 { "ago", tAGO, 1 },
365 { NULL }
366 };
367
368 /* The timezone table. */
369 /* Some of these are commented out because a time_t can't store a float. */
370 static TABLE const TimezoneTable[] = {
371 { "gmt", tZONE, HOUR( 0) }, /* Greenwich Mean */
372 { "ut", tZONE, HOUR( 0) }, /* Universal (Coordinated) */
373 { "utc", tZONE, HOUR( 0) },
374 { "wet", tZONE, HOUR( 0) }, /* Western European */
375 { "bst", tDAYZONE, HOUR( 0) }, /* British Summer */
376 { "wat", tZONE, HOUR( 1) }, /* West Africa */
377 { "at", tZONE, HOUR( 2) }, /* Azores */
378 #if 0
379 /* For completeness. BST is also British Summer, and GST is
380 * also Guam Standard. */
381 { "bst", tZONE, HOUR( 3) }, /* Brazil Standard */
382 { "gst", tZONE, HOUR( 3) }, /* Greenland Standard */
383 #endif
384 #if 0
385 { "nft", tZONE, HOUR(3.5) }, /* Newfoundland */
386 { "nst", tZONE, HOUR(3.5) }, /* Newfoundland Standard */
387 { "ndt", tDAYZONE, HOUR(3.5) }, /* Newfoundland Daylight */
388 #endif
389 { "ast", tZONE, HOUR( 4) }, /* Atlantic Standard */
390 { "adt", tDAYZONE, HOUR( 4) }, /* Atlantic Daylight */
391 { "est", tZONE, HOUR( 5) }, /* Eastern Standard */
392 { "edt", tDAYZONE, HOUR( 5) }, /* Eastern Daylight */
393 { "cst", tZONE, HOUR( 6) }, /* Central Standard */
394 { "cdt", tDAYZONE, HOUR( 6) }, /* Central Daylight */
395 { "mst", tZONE, HOUR( 7) }, /* Mountain Standard */
396 { "mdt", tDAYZONE, HOUR( 7) }, /* Mountain Daylight */
397 { "pst", tZONE, HOUR( 8) }, /* Pacific Standard */
398 { "pdt", tDAYZONE, HOUR( 8) }, /* Pacific Daylight */
399 { "yst", tZONE, HOUR( 9) }, /* Yukon Standard */
400 { "ydt", tDAYZONE, HOUR( 9) }, /* Yukon Daylight */
401 { "hst", tZONE, HOUR(10) }, /* Hawaii Standard */
402 { "hdt", tDAYZONE, HOUR(10) }, /* Hawaii Daylight */
403 { "cat", tZONE, HOUR(10) }, /* Central Alaska */
404 { "ahst", tZONE, HOUR(10) }, /* Alaska-Hawaii Standard */
405 { "nt", tZONE, HOUR(11) }, /* Nome */
406 { "idlw", tZONE, HOUR(12) }, /* International Date Line West */
407 { "cet", tZONE, -HOUR(1) }, /* Central European */
408 { "met", tZONE, -HOUR(1) }, /* Middle European */
409 { "mewt", tZONE, -HOUR(1) }, /* Middle European Winter */
410 { "mest", tDAYZONE, -HOUR(1) }, /* Middle European Summer */
411 { "swt", tZONE, -HOUR(1) }, /* Swedish Winter */
412 { "sst", tDAYZONE, -HOUR(1) }, /* Swedish Summer */
413 { "fwt", tZONE, -HOUR(1) }, /* French Winter */
414 { "fst", tDAYZONE, -HOUR(1) }, /* French Summer */
415 { "eet", tZONE, -HOUR(2) }, /* Eastern Europe, USSR Zone 1 */
416 { "bt", tZONE, -HOUR(3) }, /* Baghdad, USSR Zone 2 */
417 #if 0
418 { "it", tZONE, -HOUR(3.5) },/* Iran */
419 #endif
420 { "zp4", tZONE, -HOUR(4) }, /* USSR Zone 3 */
421 { "zp5", tZONE, -HOUR(5) }, /* USSR Zone 4 */
422 #if 0
423 { "ist", tZONE, -HOUR(5.5) },/* Indian Standard */
424 #endif
425 { "zp6", tZONE, -HOUR(6) }, /* USSR Zone 5 */
426 #if 0
427 /* For completeness. NST is also Newfoundland Stanard, and SST is
428 * also Swedish Summer. */
429 { "nst", tZONE, -HOUR(6.5) },/* North Sumatra */
430 { "sst", tZONE, -HOUR(7) }, /* South Sumatra, USSR Zone 6 */
431 #endif /* 0 */
432 { "wast", tZONE, -HOUR(7) }, /* West Australian Standard */
433 { "wadt", tDAYZONE, -HOUR(7) }, /* West Australian Daylight */
434 #if 0
435 { "jt", tZONE, -HOUR(7.5) },/* Java (3pm in Cronusland!) */
436 #endif
437 { "cct", tZONE, -HOUR(8) }, /* China Coast, USSR Zone 7 */
438 { "jst", tZONE, -HOUR(9) }, /* Japan Standard, USSR Zone 8 */
439 #if 0
440 { "cast", tZONE, -HOUR(9.5) },/* Central Australian Standard */
441 { "cadt", tDAYZONE, -HOUR(9.5) },/* Central Australian Daylight */
442 #endif
443 { "east", tZONE, -HOUR(10) }, /* Eastern Australian Standard */
444 { "eadt", tDAYZONE, -HOUR(10) }, /* Eastern Australian Daylight */
445 { "gst", tZONE, -HOUR(10) }, /* Guam Standard, USSR Zone 9 */
446 { "nzt", tZONE, -HOUR(12) }, /* New Zealand */
447 { "nzst", tZONE, -HOUR(12) }, /* New Zealand Standard */
448 { "nzdt", tDAYZONE, -HOUR(12) }, /* New Zealand Daylight */
449 { "idle", tZONE, -HOUR(12) }, /* International Date Line East */
450 { NULL }
451 };
452
453 /* Military timezone table. */
454 static TABLE const MilitaryTable[] = {
455 { "a", tZONE, HOUR( 1) },
456 { "b", tZONE, HOUR( 2) },
457 { "c", tZONE, HOUR( 3) },
458 { "d", tZONE, HOUR( 4) },
459 { "e", tZONE, HOUR( 5) },
460 { "f", tZONE, HOUR( 6) },
461 { "g", tZONE, HOUR( 7) },
462 { "h", tZONE, HOUR( 8) },
463 { "i", tZONE, HOUR( 9) },
464 { "k", tZONE, HOUR( 10) },
465 { "l", tZONE, HOUR( 11) },
466 { "m", tZONE, HOUR( 12) },
467 { "n", tZONE, HOUR(- 1) },
468 { "o", tZONE, HOUR(- 2) },
469 { "p", tZONE, HOUR(- 3) },
470 { "q", tZONE, HOUR(- 4) },
471 { "r", tZONE, HOUR(- 5) },
472 { "s", tZONE, HOUR(- 6) },
473 { "t", tZONE, HOUR(- 7) },
474 { "u", tZONE, HOUR(- 8) },
475 { "v", tZONE, HOUR(- 9) },
476 { "w", tZONE, HOUR(-10) },
477 { "x", tZONE, HOUR(-11) },
478 { "y", tZONE, HOUR(-12) },
479 { "z", tZONE, HOUR( 0) },
480 { NULL }
481 };
482
483
484 static int
yyerror(const char * s)485 yyerror(const char *s)
486 {
487 #if !defined(TEST)
488 char *str;
489
490 (void)xasprintf(&str, "parsing date string: %s", s);
491 cvs_log(LP_ERR, "%s", str);
492 free(str);
493 #endif
494 return (0);
495 }
496
497
498 static time_t
ToSeconds(time_t Hours,time_t Minutes,time_t Seconds,MERIDIAN Meridian)499 ToSeconds(time_t Hours, time_t Minutes, time_t Seconds, MERIDIAN Meridian)
500 {
501 if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59)
502 return (-1);
503
504 switch (Meridian) {
505 case MER24:
506 if (Hours < 0 || Hours > 23)
507 return (-1);
508 return (Hours * 60L + Minutes) * 60L + Seconds;
509 case MERam:
510 if (Hours < 1 || Hours > 12)
511 return (-1);
512 if (Hours == 12)
513 Hours = 0;
514 return (Hours * 60L + Minutes) * 60L + Seconds;
515 case MERpm:
516 if (Hours < 1 || Hours > 12)
517 return (-1);
518 if (Hours == 12)
519 Hours = 0;
520 return ((Hours + 12) * 60L + Minutes) * 60L + Seconds;
521 default:
522 return (-1);
523 }
524 /* NOTREACHED */
525 }
526
527
528 /* Year is either
529 * A negative number, which means to use its absolute value (why?)
530 * A number from 0 to 99, which means a year from 1900 to 1999, or
531 * The actual year (>=100).
532 */
533 static time_t
Convert(time_t Month,time_t Day,time_t Year,time_t Hours,time_t Minutes,time_t Seconds,MERIDIAN Meridian,DSTMODE DSTmode)534 Convert(time_t Month, time_t Day, time_t Year, time_t Hours, time_t Minutes,
535 time_t Seconds, MERIDIAN Meridian, DSTMODE DSTmode)
536 {
537 static int DaysInMonth[12] = {
538 31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
539 };
540 time_t tod;
541 time_t julian;
542 int i;
543
544 if (Year < 0)
545 Year = -Year;
546 if (Year < 69)
547 Year += 2000;
548 else if (Year < 100) {
549 Year += 1900;
550 if (Year < YEAR_EPOCH)
551 Year += 100;
552 }
553 DaysInMonth[1] = Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0)
554 ? 29 : 28;
555 /* XXX Sloppily check for 2038 if time_t is 32 bits */
556 if (Year < YEAR_EPOCH ||
557 (sizeof(time_t) == sizeof(int) && Year > 2038) ||
558 Month < 1 || Month > 12 ||
559 /* Lint fluff: "conversion from long may lose accuracy" */
560 Day < 1 || Day > DaysInMonth[(int)--Month])
561 return (-1);
562
563 for (julian = Day - 1, i = 0; i < Month; i++)
564 julian += DaysInMonth[i];
565
566 for (i = YEAR_EPOCH; i < Year; i++)
567 julian += 365 + (i % 4 == 0);
568 julian *= SECSPERDAY;
569 julian += yyTimezone * 60L;
570
571 if ((tod = ToSeconds(Hours, Minutes, Seconds, Meridian)) < 0)
572 return (-1);
573 julian += tod;
574 if ((DSTmode == DSTon) ||
575 (DSTmode == DSTmaybe && localtime(&julian)->tm_isdst))
576 julian -= 60 * 60;
577 return (julian);
578 }
579
580
581 static time_t
DSTcorrect(time_t Start,time_t Future)582 DSTcorrect(time_t Start, time_t Future)
583 {
584 time_t StartDay;
585 time_t FutureDay;
586
587 StartDay = (localtime(&Start)->tm_hour + 1) % 24;
588 FutureDay = (localtime(&Future)->tm_hour + 1) % 24;
589 return (Future - Start) + (StartDay - FutureDay) * 60L * 60L;
590 }
591
592
593 static time_t
RelativeDate(time_t Start,time_t DayOrdinal,time_t DayNumber)594 RelativeDate(time_t Start, time_t DayOrdinal, time_t DayNumber)
595 {
596 struct tm *tm;
597 time_t now;
598
599 now = Start;
600 tm = localtime(&now);
601 now += SECSPERDAY * ((DayNumber - tm->tm_wday + 7) % 7);
602 now += 7 * SECSPERDAY * (DayOrdinal <= 0 ? DayOrdinal : DayOrdinal - 1);
603 return DSTcorrect(Start, now);
604 }
605
606
607 static time_t
RelativeMonth(time_t Start,time_t RelMonth)608 RelativeMonth(time_t Start, time_t RelMonth)
609 {
610 struct tm *tm;
611 time_t Month;
612 time_t Year;
613
614 if (RelMonth == 0)
615 return (0);
616 tm = localtime(&Start);
617 Month = 12 * (tm->tm_year + 1900) + tm->tm_mon + RelMonth;
618 Year = Month / 12;
619 Month = Month % 12 + 1;
620 return DSTcorrect(Start,
621 Convert(Month, (time_t)tm->tm_mday, Year,
622 (time_t)tm->tm_hour, (time_t)tm->tm_min, (time_t)tm->tm_sec,
623 MER24, DSTmaybe));
624 }
625
626
627 static int
lookup(char * buff)628 lookup(char *buff)
629 {
630 size_t len;
631 char *p, *q;
632 int i, abbrev;
633 const TABLE *tp;
634
635 /* Make it lowercase. */
636 for (p = buff; *p; p++)
637 if (isupper(*p))
638 *p = tolower(*p);
639
640 if (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0) {
641 yylval.Meridian = MERam;
642 return (tMERIDIAN);
643 }
644 if (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0) {
645 yylval.Meridian = MERpm;
646 return (tMERIDIAN);
647 }
648
649 len = strlen(buff);
650 /* See if we have an abbreviation for a month. */
651 if (len == 3)
652 abbrev = 1;
653 else if (len == 4 && buff[3] == '.') {
654 abbrev = 1;
655 buff[3] = '\0';
656 --len;
657 } else
658 abbrev = 0;
659
660 for (tp = MonthDayTable; tp->name; tp++) {
661 if (abbrev) {
662 if (strncmp(buff, tp->name, 3) == 0) {
663 yylval.Number = tp->value;
664 return (tp->type);
665 }
666 } else if (strcmp(buff, tp->name) == 0) {
667 yylval.Number = tp->value;
668 return (tp->type);
669 }
670 }
671
672 for (tp = TimezoneTable; tp->name; tp++)
673 if (strcmp(buff, tp->name) == 0) {
674 yylval.Number = tp->value;
675 return (tp->type);
676 }
677
678 if (strcmp(buff, "dst") == 0)
679 return (tDST);
680
681 for (tp = UnitsTable; tp->name; tp++)
682 if (strcmp(buff, tp->name) == 0) {
683 yylval.Number = tp->value;
684 return (tp->type);
685 }
686
687 /* Strip off any plural and try the units table again. */
688 if (len != 0 && buff[len - 1] == 's') {
689 buff[len - 1] = '\0';
690 for (tp = UnitsTable; tp->name; tp++)
691 if (strcmp(buff, tp->name) == 0) {
692 yylval.Number = tp->value;
693 return (tp->type);
694 }
695 buff[len - 1] = 's'; /* Put back for "this" in OtherTable. */
696 }
697
698 for (tp = OtherTable; tp->name; tp++)
699 if (strcmp(buff, tp->name) == 0) {
700 yylval.Number = tp->value;
701 return (tp->type);
702 }
703
704 /* Military timezones. */
705 if (len == 1 && isalpha(*buff)) {
706 for (tp = MilitaryTable; tp->name; tp++)
707 if (strcmp(buff, tp->name) == 0) {
708 yylval.Number = tp->value;
709 return (tp->type);
710 }
711 }
712
713 /* Drop out any periods and try the timezone table again. */
714 for (i = 0, p = q = buff; *q; q++)
715 if (*q != '.')
716 *p++ = *q;
717 else
718 i++;
719 *p = '\0';
720 if (i)
721 for (tp = TimezoneTable; tp->name; tp++)
722 if (strcmp(buff, tp->name) == 0) {
723 yylval.Number = tp->value;
724 return (tp->type);
725 }
726
727 return (tID);
728 }
729
730
731 static int
yylex(void)732 yylex(void)
733 {
734 char c, *p, buff[20];
735 int count, sign;
736
737 for (;;) {
738 while (isspace(*yyInput))
739 yyInput++;
740
741 if (isdigit(c = *yyInput) || c == '-' || c == '+') {
742 if (c == '-' || c == '+') {
743 sign = c == '-' ? -1 : 1;
744 if (!isdigit(*++yyInput))
745 /* skip the '-' sign */
746 continue;
747 }
748 else
749 sign = 0;
750
751 for (yylval.Number = 0; isdigit(c = *yyInput++); )
752 yylval.Number = 10 * yylval.Number + c - '0';
753 yyInput--;
754 if (sign < 0)
755 yylval.Number = -yylval.Number;
756 return sign ? tSNUMBER : tUNUMBER;
757 }
758
759 if (isalpha(c)) {
760 for (p = buff; isalpha(c = *yyInput++) || c == '.'; )
761 if (p < &buff[sizeof buff - 1])
762 *p++ = c;
763 *p = '\0';
764 yyInput--;
765 return lookup(buff);
766 }
767 if (c != '(')
768 return *yyInput++;
769
770 count = 0;
771 do {
772 c = *yyInput++;
773 if (c == '\0')
774 return (c);
775 if (c == '(')
776 count++;
777 else if (c == ')')
778 count--;
779 } while (count > 0);
780 }
781 }
782
783 /* Yield A - B, measured in seconds. */
784 static long
difftm(struct tm * a,struct tm * b)785 difftm(struct tm *a, struct tm *b)
786 {
787 int ay = a->tm_year + (YEAR_TMORIGIN - 1);
788 int by = b->tm_year + (YEAR_TMORIGIN - 1);
789 int days = (
790 /* difference in day of year */
791 a->tm_yday - b->tm_yday
792 /* + intervening leap days */
793 + ((ay >> 2) - (by >> 2))
794 - (ay/100 - by/100)
795 + ((ay/100 >> 2) - (by/100 >> 2))
796 /* + difference in years * 365 */
797 + (long)(ay-by) * 365);
798 return (60 * (60 * (24 * days + (a->tm_hour - b->tm_hour))
799 + (a->tm_min - b->tm_min)) + (a->tm_sec - b->tm_sec));
800 }
801
802 /*
803 * date_parse()
804 *
805 * Returns the number of seconds since the Epoch corresponding to the date.
806 */
807 time_t
date_parse(const char * p)808 date_parse(const char *p)
809 {
810 struct tm gmt, tm;
811 time_t Start, tod, nowtime, tz;
812
813 yyInput = p;
814
815 if (time(&nowtime) == -1 || !gmtime_r(&nowtime, &gmt) ||
816 !localtime_r(&nowtime, &tm))
817 return -1;
818
819 tz = difftm(&gmt, &tm) / 60;
820
821 if (tm.tm_isdst)
822 tz += 60;
823
824 yyYear = tm.tm_year + 1900;
825 yyMonth = tm.tm_mon + 1;
826 yyDay = tm.tm_mday;
827 yyTimezone = tz;
828 yyDSTmode = DSTmaybe;
829 yyHour = 0;
830 yyMinutes = 0;
831 yySeconds = 0;
832 yyMeridian = MER24;
833 yyRelSeconds = 0;
834 yyRelMonth = 0;
835 yyHaveDate = 0;
836 yyHaveDay = 0;
837 yyHaveRel = 0;
838 yyHaveTime = 0;
839 yyHaveZone = 0;
840
841 if (yyparse() || yyHaveTime > 1 || yyHaveZone > 1 ||
842 yyHaveDate > 1 || yyHaveDay > 1)
843 return (-1);
844
845 if (yyHaveDate || yyHaveTime || yyHaveDay) {
846 Start = Convert(yyMonth, yyDay, yyYear, yyHour, yyMinutes,
847 yySeconds, yyMeridian, yyDSTmode);
848 if (Start < 0)
849 return (-1);
850 } else {
851 Start = nowtime;
852 if (!yyHaveRel)
853 Start -= ((tm.tm_hour * 60L + tm.tm_min) * 60L) +
854 tm.tm_sec;
855 }
856
857 Start += yyRelSeconds;
858 Start += RelativeMonth(Start, yyRelMonth);
859
860 if (yyHaveDay && !yyHaveDate) {
861 tod = RelativeDate(Start, yyDayOrdinal, yyDayNumber);
862 Start += tod;
863 }
864
865 return Start;
866 }
867
868 #if defined(TEST)
869 int
main(int argc,char ** argv)870 main(int argc, char **argv)
871 {
872 char buff[128];
873 time_t d;
874
875 (void)printf("Enter date, or blank line to exit.\n\t> ");
876 (void)fflush(stdout);
877 while (fgets(buff, sizeof(buff), stdin) && buff[0]) {
878 d = date_parse(buff);
879 if (d == -1)
880 (void)printf("Bad format - couldn't convert.\n");
881 else
882 (void)printf("%s", ctime(&d));
883 (void)printf("\t> ");
884 (void)fflush(stdout);
885 }
886
887 return (0);
888 }
889 #endif /* defined(TEST) */
890