The seventh batch
[git.git] / date.c
blobf9ea807b3a9f9ee64a4173fa923f31b00455e840
1 /*
2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
5 */
7 #include "cache.h"
9 /*
10 * This is like mktime, but without normalization of tm_wday and tm_yday.
12 static time_t tm_to_time_t(const struct tm *tm)
14 static const int mdays[] = {
15 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
17 int year = tm->tm_year - 70;
18 int month = tm->tm_mon;
19 int day = tm->tm_mday;
21 if (year < 0 || year > 129) /* algo only works for 1970-2099 */
22 return -1;
23 if (month < 0 || month > 11) /* array bounds */
24 return -1;
25 if (month < 2 || (year + 2) % 4)
26 day--;
27 if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_sec < 0)
28 return -1;
29 return (year * 365 + (year + 1) / 4 + mdays[month] + day) * 24*60*60UL +
30 tm->tm_hour * 60*60 + tm->tm_min * 60 + tm->tm_sec;
33 static const char *month_names[] = {
34 "January", "February", "March", "April", "May", "June",
35 "July", "August", "September", "October", "November", "December"
38 static const char *weekday_names[] = {
39 "Sundays", "Mondays", "Tuesdays", "Wednesdays", "Thursdays", "Fridays", "Saturdays"
42 static time_t gm_time_t(timestamp_t time, int tz)
44 int minutes;
46 minutes = tz < 0 ? -tz : tz;
47 minutes = (minutes / 100)*60 + (minutes % 100);
48 minutes = tz < 0 ? -minutes : minutes;
50 if (minutes > 0) {
51 if (unsigned_add_overflows(time, minutes * 60))
52 die("Timestamp+tz too large: %"PRItime" +%04d",
53 time, tz);
54 } else if (time < -minutes * 60)
55 die("Timestamp before Unix epoch: %"PRItime" %04d", time, tz);
56 time += minutes * 60;
57 if (date_overflows(time))
58 die("Timestamp too large for this system: %"PRItime, time);
59 return (time_t)time;
63 * The "tz" thing is passed in as this strange "decimal parse of tz"
64 * thing, which means that tz -0100 is passed in as the integer -100,
65 * even though it means "sixty minutes off"
67 static struct tm *time_to_tm(timestamp_t time, int tz, struct tm *tm)
69 time_t t = gm_time_t(time, tz);
70 return gmtime_r(&t, tm);
73 static struct tm *time_to_tm_local(timestamp_t time, struct tm *tm)
75 time_t t = time;
76 return localtime_r(&t, tm);
80 * Fill in the localtime 'struct tm' for the supplied time,
81 * and return the local tz.
83 static int local_time_tzoffset(time_t t, struct tm *tm)
85 time_t t_local;
86 int offset, eastwest;
88 localtime_r(&t, tm);
89 t_local = tm_to_time_t(tm);
90 if (t_local == -1)
91 return 0; /* error; just use +0000 */
92 if (t_local < t) {
93 eastwest = -1;
94 offset = t - t_local;
95 } else {
96 eastwest = 1;
97 offset = t_local - t;
99 offset /= 60; /* in minutes */
100 offset = (offset % 60) + ((offset / 60) * 100);
101 return offset * eastwest;
105 * What value of "tz" was in effect back then at "time" in the
106 * local timezone?
108 static int local_tzoffset(timestamp_t time)
110 struct tm tm;
112 if (date_overflows(time))
113 die("Timestamp too large for this system: %"PRItime, time);
115 return local_time_tzoffset((time_t)time, &tm);
118 static void get_time(struct timeval *now)
120 const char *x;
122 x = getenv("GIT_TEST_DATE_NOW");
123 if (x) {
124 now->tv_sec = atoi(x);
125 now->tv_usec = 0;
127 else
128 gettimeofday(now, NULL);
131 void show_date_relative(timestamp_t time, struct strbuf *timebuf)
133 struct timeval now;
134 timestamp_t diff;
136 get_time(&now);
137 if (now.tv_sec < time) {
138 strbuf_addstr(timebuf, _("in the future"));
139 return;
141 diff = now.tv_sec - time;
142 if (diff < 90) {
143 strbuf_addf(timebuf,
144 Q_("%"PRItime" second ago", "%"PRItime" seconds ago", diff), diff);
145 return;
147 /* Turn it into minutes */
148 diff = (diff + 30) / 60;
149 if (diff < 90) {
150 strbuf_addf(timebuf,
151 Q_("%"PRItime" minute ago", "%"PRItime" minutes ago", diff), diff);
152 return;
154 /* Turn it into hours */
155 diff = (diff + 30) / 60;
156 if (diff < 36) {
157 strbuf_addf(timebuf,
158 Q_("%"PRItime" hour ago", "%"PRItime" hours ago", diff), diff);
159 return;
161 /* We deal with number of days from here on */
162 diff = (diff + 12) / 24;
163 if (diff < 14) {
164 strbuf_addf(timebuf,
165 Q_("%"PRItime" day ago", "%"PRItime" days ago", diff), diff);
166 return;
168 /* Say weeks for the past 10 weeks or so */
169 if (diff < 70) {
170 strbuf_addf(timebuf,
171 Q_("%"PRItime" week ago", "%"PRItime" weeks ago", (diff + 3) / 7),
172 (diff + 3) / 7);
173 return;
175 /* Say months for the past 12 months or so */
176 if (diff < 365) {
177 strbuf_addf(timebuf,
178 Q_("%"PRItime" month ago", "%"PRItime" months ago", (diff + 15) / 30),
179 (diff + 15) / 30);
180 return;
182 /* Give years and months for 5 years or so */
183 if (diff < 1825) {
184 timestamp_t totalmonths = (diff * 12 * 2 + 365) / (365 * 2);
185 timestamp_t years = totalmonths / 12;
186 timestamp_t months = totalmonths % 12;
187 if (months) {
188 struct strbuf sb = STRBUF_INIT;
189 strbuf_addf(&sb, Q_("%"PRItime" year", "%"PRItime" years", years), years);
190 strbuf_addf(timebuf,
191 /* TRANSLATORS: "%s" is "<n> years" */
192 Q_("%s, %"PRItime" month ago", "%s, %"PRItime" months ago", months),
193 sb.buf, months);
194 strbuf_release(&sb);
195 } else
196 strbuf_addf(timebuf,
197 Q_("%"PRItime" year ago", "%"PRItime" years ago", years), years);
198 return;
200 /* Otherwise, just years. Centuries is probably overkill. */
201 strbuf_addf(timebuf,
202 Q_("%"PRItime" year ago", "%"PRItime" years ago", (diff + 183) / 365),
203 (diff + 183) / 365);
206 struct date_mode *date_mode_from_type(enum date_mode_type type)
208 static struct date_mode mode;
209 if (type == DATE_STRFTIME)
210 BUG("cannot create anonymous strftime date_mode struct");
211 mode.type = type;
212 mode.local = 0;
213 return &mode;
216 static void show_date_normal(struct strbuf *buf, timestamp_t time, struct tm *tm, int tz, struct tm *human_tm, int human_tz, int local)
218 struct {
219 unsigned int year:1,
220 date:1,
221 wday:1,
222 time:1,
223 seconds:1,
224 tz:1;
225 } hide = { 0 };
227 hide.tz = local || tz == human_tz;
228 hide.year = tm->tm_year == human_tm->tm_year;
229 if (hide.year) {
230 if (tm->tm_mon == human_tm->tm_mon) {
231 if (tm->tm_mday > human_tm->tm_mday) {
232 /* Future date: think timezones */
233 } else if (tm->tm_mday == human_tm->tm_mday) {
234 hide.date = hide.wday = 1;
235 } else if (tm->tm_mday + 5 > human_tm->tm_mday) {
236 /* Leave just weekday if it was a few days ago */
237 hide.date = 1;
242 /* Show "today" times as just relative times */
243 if (hide.wday) {
244 show_date_relative(time, buf);
245 return;
249 * Always hide seconds for human-readable.
250 * Hide timezone if showing date.
251 * Hide weekday and time if showing year.
253 * The logic here is two-fold:
254 * (a) only show details when recent enough to matter
255 * (b) keep the maximum length "similar", and in check
257 if (human_tm->tm_year) {
258 hide.seconds = 1;
259 hide.tz |= !hide.date;
260 hide.wday = hide.time = !hide.year;
263 if (!hide.wday)
264 strbuf_addf(buf, "%.3s ", weekday_names[tm->tm_wday]);
265 if (!hide.date)
266 strbuf_addf(buf, "%.3s %d ", month_names[tm->tm_mon], tm->tm_mday);
268 /* Do we want AM/PM depending on locale? */
269 if (!hide.time) {
270 strbuf_addf(buf, "%02d:%02d", tm->tm_hour, tm->tm_min);
271 if (!hide.seconds)
272 strbuf_addf(buf, ":%02d", tm->tm_sec);
273 } else
274 strbuf_rtrim(buf);
276 if (!hide.year)
277 strbuf_addf(buf, " %d", tm->tm_year + 1900);
279 if (!hide.tz)
280 strbuf_addf(buf, " %+05d", tz);
283 const char *show_date(timestamp_t time, int tz, const struct date_mode *mode)
285 struct tm *tm;
286 struct tm tmbuf = { 0 };
287 struct tm human_tm = { 0 };
288 int human_tz = -1;
289 static struct strbuf timebuf = STRBUF_INIT;
291 if (mode->type == DATE_UNIX) {
292 strbuf_reset(&timebuf);
293 strbuf_addf(&timebuf, "%"PRItime, time);
294 return timebuf.buf;
297 if (mode->type == DATE_HUMAN) {
298 struct timeval now;
300 get_time(&now);
302 /* Fill in the data for "current time" in human_tz and human_tm */
303 human_tz = local_time_tzoffset(now.tv_sec, &human_tm);
306 if (mode->local)
307 tz = local_tzoffset(time);
309 if (mode->type == DATE_RAW) {
310 strbuf_reset(&timebuf);
311 strbuf_addf(&timebuf, "%"PRItime" %+05d", time, tz);
312 return timebuf.buf;
315 if (mode->type == DATE_RELATIVE) {
316 strbuf_reset(&timebuf);
317 show_date_relative(time, &timebuf);
318 return timebuf.buf;
321 if (mode->local)
322 tm = time_to_tm_local(time, &tmbuf);
323 else
324 tm = time_to_tm(time, tz, &tmbuf);
325 if (!tm) {
326 tm = time_to_tm(0, 0, &tmbuf);
327 tz = 0;
330 strbuf_reset(&timebuf);
331 if (mode->type == DATE_SHORT)
332 strbuf_addf(&timebuf, "%04d-%02d-%02d", tm->tm_year + 1900,
333 tm->tm_mon + 1, tm->tm_mday);
334 else if (mode->type == DATE_ISO8601)
335 strbuf_addf(&timebuf, "%04d-%02d-%02d %02d:%02d:%02d %+05d",
336 tm->tm_year + 1900,
337 tm->tm_mon + 1,
338 tm->tm_mday,
339 tm->tm_hour, tm->tm_min, tm->tm_sec,
340 tz);
341 else if (mode->type == DATE_ISO8601_STRICT) {
342 char sign = (tz >= 0) ? '+' : '-';
343 tz = abs(tz);
344 strbuf_addf(&timebuf, "%04d-%02d-%02dT%02d:%02d:%02d%c%02d:%02d",
345 tm->tm_year + 1900,
346 tm->tm_mon + 1,
347 tm->tm_mday,
348 tm->tm_hour, tm->tm_min, tm->tm_sec,
349 sign, tz / 100, tz % 100);
350 } else if (mode->type == DATE_RFC2822)
351 strbuf_addf(&timebuf, "%.3s, %d %.3s %d %02d:%02d:%02d %+05d",
352 weekday_names[tm->tm_wday], tm->tm_mday,
353 month_names[tm->tm_mon], tm->tm_year + 1900,
354 tm->tm_hour, tm->tm_min, tm->tm_sec, tz);
355 else if (mode->type == DATE_STRFTIME)
356 strbuf_addftime(&timebuf, mode->strftime_fmt, tm, tz,
357 !mode->local);
358 else
359 show_date_normal(&timebuf, time, tm, tz, &human_tm, human_tz, mode->local);
360 return timebuf.buf;
364 * Check these. And note how it doesn't do the summer-time conversion.
366 * In my world, it's always summer, and things are probably a bit off
367 * in other ways too.
369 static const struct {
370 const char *name;
371 int offset;
372 int dst;
373 } timezone_names[] = {
374 { "IDLW", -12, 0, }, /* International Date Line West */
375 { "NT", -11, 0, }, /* Nome */
376 { "CAT", -10, 0, }, /* Central Alaska */
377 { "HST", -10, 0, }, /* Hawaii Standard */
378 { "HDT", -10, 1, }, /* Hawaii Daylight */
379 { "YST", -9, 0, }, /* Yukon Standard */
380 { "YDT", -9, 1, }, /* Yukon Daylight */
381 { "PST", -8, 0, }, /* Pacific Standard */
382 { "PDT", -8, 1, }, /* Pacific Daylight */
383 { "MST", -7, 0, }, /* Mountain Standard */
384 { "MDT", -7, 1, }, /* Mountain Daylight */
385 { "CST", -6, 0, }, /* Central Standard */
386 { "CDT", -6, 1, }, /* Central Daylight */
387 { "EST", -5, 0, }, /* Eastern Standard */
388 { "EDT", -5, 1, }, /* Eastern Daylight */
389 { "AST", -3, 0, }, /* Atlantic Standard */
390 { "ADT", -3, 1, }, /* Atlantic Daylight */
391 { "WAT", -1, 0, }, /* West Africa */
393 { "GMT", 0, 0, }, /* Greenwich Mean */
394 { "UTC", 0, 0, }, /* Universal (Coordinated) */
395 { "Z", 0, 0, }, /* Zulu, alias for UTC */
397 { "WET", 0, 0, }, /* Western European */
398 { "BST", 0, 1, }, /* British Summer */
399 { "CET", +1, 0, }, /* Central European */
400 { "MET", +1, 0, }, /* Middle European */
401 { "MEWT", +1, 0, }, /* Middle European Winter */
402 { "MEST", +1, 1, }, /* Middle European Summer */
403 { "CEST", +1, 1, }, /* Central European Summer */
404 { "MESZ", +1, 1, }, /* Middle European Summer */
405 { "FWT", +1, 0, }, /* French Winter */
406 { "FST", +1, 1, }, /* French Summer */
407 { "EET", +2, 0, }, /* Eastern Europe, USSR Zone 1 */
408 { "EEST", +2, 1, }, /* Eastern European Daylight */
409 { "WAST", +7, 0, }, /* West Australian Standard */
410 { "WADT", +7, 1, }, /* West Australian Daylight */
411 { "CCT", +8, 0, }, /* China Coast, USSR Zone 7 */
412 { "JST", +9, 0, }, /* Japan Standard, USSR Zone 8 */
413 { "EAST", +10, 0, }, /* Eastern Australian Standard */
414 { "EADT", +10, 1, }, /* Eastern Australian Daylight */
415 { "GST", +10, 0, }, /* Guam Standard, USSR Zone 9 */
416 { "NZT", +12, 0, }, /* New Zealand */
417 { "NZST", +12, 0, }, /* New Zealand Standard */
418 { "NZDT", +12, 1, }, /* New Zealand Daylight */
419 { "IDLE", +12, 0, }, /* International Date Line East */
422 static int match_string(const char *date, const char *str)
424 int i = 0;
426 for (i = 0; *date; date++, str++, i++) {
427 if (*date == *str)
428 continue;
429 if (toupper(*date) == toupper(*str))
430 continue;
431 if (!isalnum(*date))
432 break;
433 return 0;
435 return i;
438 static int skip_alpha(const char *date)
440 int i = 0;
441 do {
442 i++;
443 } while (isalpha(date[i]));
444 return i;
448 * Parse month, weekday, or timezone name
450 static int match_alpha(const char *date, struct tm *tm, int *offset)
452 int i;
454 for (i = 0; i < 12; i++) {
455 int match = match_string(date, month_names[i]);
456 if (match >= 3) {
457 tm->tm_mon = i;
458 return match;
462 for (i = 0; i < 7; i++) {
463 int match = match_string(date, weekday_names[i]);
464 if (match >= 3) {
465 tm->tm_wday = i;
466 return match;
470 for (i = 0; i < ARRAY_SIZE(timezone_names); i++) {
471 int match = match_string(date, timezone_names[i].name);
472 if (match >= 3 || match == strlen(timezone_names[i].name)) {
473 int off = timezone_names[i].offset;
475 /* This is bogus, but we like summer */
476 off += timezone_names[i].dst;
478 /* Only use the tz name offset if we don't have anything better */
479 if (*offset == -1)
480 *offset = 60*off;
482 return match;
486 if (match_string(date, "PM") == 2) {
487 tm->tm_hour = (tm->tm_hour % 12) + 12;
488 return 2;
491 if (match_string(date, "AM") == 2) {
492 tm->tm_hour = (tm->tm_hour % 12) + 0;
493 return 2;
496 /* BAD CRAP */
497 return skip_alpha(date);
500 static int set_date(int year, int month, int day, struct tm *now_tm, time_t now, struct tm *tm)
502 if (month > 0 && month < 13 && day > 0 && day < 32) {
503 struct tm check = *tm;
504 struct tm *r = (now_tm ? &check : tm);
505 time_t specified;
507 r->tm_mon = month - 1;
508 r->tm_mday = day;
509 if (year == -1) {
510 if (!now_tm)
511 return 1;
512 r->tm_year = now_tm->tm_year;
514 else if (year >= 1970 && year < 2100)
515 r->tm_year = year - 1900;
516 else if (year > 70 && year < 100)
517 r->tm_year = year;
518 else if (year < 38)
519 r->tm_year = year + 100;
520 else
521 return -1;
522 if (!now_tm)
523 return 0;
525 specified = tm_to_time_t(r);
527 /* Be it commit time or author time, it does not make
528 * sense to specify timestamp way into the future. Make
529 * sure it is not later than ten days from now...
531 if ((specified != -1) && (now + 10*24*3600 < specified))
532 return -1;
533 tm->tm_mon = r->tm_mon;
534 tm->tm_mday = r->tm_mday;
535 if (year != -1)
536 tm->tm_year = r->tm_year;
537 return 0;
539 return -1;
542 static int set_time(long hour, long minute, long second, struct tm *tm)
544 /* We accept 61st second because of leap second */
545 if (0 <= hour && hour <= 24 &&
546 0 <= minute && minute < 60 &&
547 0 <= second && second <= 60) {
548 tm->tm_hour = hour;
549 tm->tm_min = minute;
550 tm->tm_sec = second;
551 return 0;
553 return -1;
556 static int is_date_known(struct tm *tm)
558 return tm->tm_year != -1 && tm->tm_mon != -1 && tm->tm_mday != -1;
561 static int match_multi_number(timestamp_t num, char c, const char *date,
562 char *end, struct tm *tm, time_t now)
564 struct tm now_tm;
565 struct tm *refuse_future;
566 long num2, num3;
568 num2 = strtol(end+1, &end, 10);
569 num3 = -1;
570 if (*end == c && isdigit(end[1]))
571 num3 = strtol(end+1, &end, 10);
573 /* Time? Date? */
574 switch (c) {
575 case ':':
576 if (num3 < 0)
577 num3 = 0;
578 if (set_time(num, num2, num3, tm) == 0) {
580 * If %H:%M:%S was just parsed followed by: .<num4>
581 * Consider (& discard) it as fractional second
582 * if %Y%m%d is parsed before.
584 if (*end == '.' && isdigit(end[1]) && is_date_known(tm))
585 strtol(end + 1, &end, 10);
586 break;
588 return 0;
590 case '-':
591 case '/':
592 case '.':
593 if (!now)
594 now = time(NULL);
595 refuse_future = NULL;
596 if (gmtime_r(&now, &now_tm))
597 refuse_future = &now_tm;
599 if (num > 70) {
600 /* yyyy-mm-dd? */
601 if (set_date(num, num2, num3, NULL, now, tm) == 0)
602 break;
603 /* yyyy-dd-mm? */
604 if (set_date(num, num3, num2, NULL, now, tm) == 0)
605 break;
607 /* Our eastern European friends say dd.mm.yy[yy]
608 * is the norm there, so giving precedence to
609 * mm/dd/yy[yy] form only when separator is not '.'
611 if (c != '.' &&
612 set_date(num3, num, num2, refuse_future, now, tm) == 0)
613 break;
614 /* European dd.mm.yy[yy] or funny US dd/mm/yy[yy] */
615 if (set_date(num3, num2, num, refuse_future, now, tm) == 0)
616 break;
617 /* Funny European mm.dd.yy */
618 if (c == '.' &&
619 set_date(num3, num, num2, refuse_future, now, tm) == 0)
620 break;
621 return 0;
623 return end - date;
627 * Have we filled in any part of the time/date yet?
628 * We just do a binary 'and' to see if the sign bit
629 * is set in all the values.
631 static inline int nodate(struct tm *tm)
633 return (tm->tm_year &
634 tm->tm_mon &
635 tm->tm_mday &
636 tm->tm_hour &
637 tm->tm_min &
638 tm->tm_sec) < 0;
642 * We've seen a digit. Time? Year? Date?
644 static int match_digit(const char *date, struct tm *tm, int *offset, int *tm_gmt)
646 int n;
647 char *end;
648 timestamp_t num;
650 num = parse_timestamp(date, &end, 10);
653 * Seconds since 1970? We trigger on that for any numbers with
654 * more than 8 digits. This is because we don't want to rule out
655 * numbers like 20070606 as a YYYYMMDD date.
657 if (num >= 100000000 && nodate(tm)) {
658 time_t time = num;
659 if (gmtime_r(&time, tm)) {
660 *tm_gmt = 1;
661 return end - date;
666 * Check for special formats: num[-.:/]num[same]num
668 switch (*end) {
669 case ':':
670 case '.':
671 case '/':
672 case '-':
673 if (isdigit(end[1])) {
674 int match = match_multi_number(num, *end, date, end, tm, 0);
675 if (match)
676 return match;
681 * None of the special formats? Try to guess what
682 * the number meant. We use the number of digits
683 * to make a more educated guess..
685 n = 0;
686 do {
687 n++;
688 } while (isdigit(date[n]));
690 /* 8 digits, compact style of ISO-8601's date: YYYYmmDD */
691 /* 6 digits, compact style of ISO-8601's time: HHMMSS */
692 if (n == 8 || n == 6) {
693 unsigned int num1 = num / 10000;
694 unsigned int num2 = (num % 10000) / 100;
695 unsigned int num3 = num % 100;
696 if (n == 8)
697 set_date(num1, num2, num3, NULL, time(NULL), tm);
698 else if (n == 6 && set_time(num1, num2, num3, tm) == 0 &&
699 *end == '.' && isdigit(end[1]))
700 strtoul(end + 1, &end, 10);
701 return end - date;
704 /* Four-digit year or a timezone? */
705 if (n == 4) {
706 if (num <= 1400 && *offset == -1) {
707 unsigned int minutes = num % 100;
708 unsigned int hours = num / 100;
709 *offset = hours*60 + minutes;
710 } else if (num > 1900 && num < 2100)
711 tm->tm_year = num - 1900;
712 return n;
716 * Ignore lots of numerals. We took care of 4-digit years above.
717 * Days or months must be one or two digits.
719 if (n > 2)
720 return n;
723 * NOTE! We will give precedence to day-of-month over month or
724 * year numbers in the 1-12 range. So 05 is always "mday 5",
725 * unless we already have a mday..
727 * IOW, 01 Apr 05 parses as "April 1st, 2005".
729 if (num > 0 && num < 32 && tm->tm_mday < 0) {
730 tm->tm_mday = num;
731 return n;
734 /* Two-digit year? */
735 if (n == 2 && tm->tm_year < 0) {
736 if (num < 10 && tm->tm_mday >= 0) {
737 tm->tm_year = num + 100;
738 return n;
740 if (num >= 70) {
741 tm->tm_year = num;
742 return n;
746 if (num > 0 && num < 13 && tm->tm_mon < 0)
747 tm->tm_mon = num-1;
749 return n;
752 static int match_tz(const char *date, int *offp)
754 char *end;
755 int hour = strtoul(date + 1, &end, 10);
756 int n = end - (date + 1);
757 int min = 0;
759 if (n == 4) {
760 /* hhmm */
761 min = hour % 100;
762 hour = hour / 100;
763 } else if (n != 2) {
764 min = 99; /* random crap */
765 } else if (*end == ':') {
766 /* hh:mm? */
767 min = strtoul(end + 1, &end, 10);
768 if (end - (date + 1) != 5)
769 min = 99; /* random crap */
770 } /* otherwise we parsed "hh" */
773 * Don't accept any random crap. Even though some places have
774 * offset larger than 12 hours (e.g. Pacific/Kiritimati is at
775 * UTC+14), there is something wrong if hour part is much
776 * larger than that. We might also want to check that the
777 * minutes are divisible by 15 or something too. (Offset of
778 * Kathmandu, Nepal is UTC+5:45)
780 if (min < 60 && hour < 24) {
781 int offset = hour * 60 + min;
782 if (*date == '-')
783 offset = -offset;
784 *offp = offset;
786 return end - date;
789 static void date_string(timestamp_t date, int offset, struct strbuf *buf)
791 int sign = '+';
793 if (offset < 0) {
794 offset = -offset;
795 sign = '-';
797 strbuf_addf(buf, "%"PRItime" %c%02d%02d", date, sign, offset / 60, offset % 60);
801 * Parse a string like "0 +0000" as ancient timestamp near epoch, but
802 * only when it appears not as part of any other string.
804 static int match_object_header_date(const char *date, timestamp_t *timestamp, int *offset)
806 char *end;
807 timestamp_t stamp;
808 int ofs;
810 if (*date < '0' || '9' < *date)
811 return -1;
812 stamp = parse_timestamp(date, &end, 10);
813 if (*end != ' ' || stamp == TIME_MAX || (end[1] != '+' && end[1] != '-'))
814 return -1;
815 date = end + 2;
816 ofs = strtol(date, &end, 10);
817 if ((*end != '\0' && (*end != '\n')) || end != date + 4)
818 return -1;
819 ofs = (ofs / 100) * 60 + (ofs % 100);
820 if (date[-1] == '-')
821 ofs = -ofs;
822 *timestamp = stamp;
823 *offset = ofs;
824 return 0;
827 /* Gr. strptime is crap for this; it doesn't have a way to require RFC2822
828 (i.e. English) day/month names, and it doesn't work correctly with %z. */
829 int parse_date_basic(const char *date, timestamp_t *timestamp, int *offset)
831 struct tm tm;
832 int tm_gmt;
833 timestamp_t dummy_timestamp;
834 int dummy_offset;
836 if (!timestamp)
837 timestamp = &dummy_timestamp;
838 if (!offset)
839 offset = &dummy_offset;
841 memset(&tm, 0, sizeof(tm));
842 tm.tm_year = -1;
843 tm.tm_mon = -1;
844 tm.tm_mday = -1;
845 tm.tm_isdst = -1;
846 tm.tm_hour = -1;
847 tm.tm_min = -1;
848 tm.tm_sec = -1;
849 *offset = -1;
850 tm_gmt = 0;
852 if (*date == '@' &&
853 !match_object_header_date(date + 1, timestamp, offset))
854 return 0; /* success */
855 for (;;) {
856 int match = 0;
857 unsigned char c = *date;
859 /* Stop at end of string or newline */
860 if (!c || c == '\n')
861 break;
863 if (isalpha(c))
864 match = match_alpha(date, &tm, offset);
865 else if (isdigit(c))
866 match = match_digit(date, &tm, offset, &tm_gmt);
867 else if ((c == '-' || c == '+') && isdigit(date[1]))
868 match = match_tz(date, offset);
870 if (!match) {
871 /* BAD CRAP */
872 match = 1;
875 date += match;
878 /* do not use mktime(), which uses local timezone, here */
879 *timestamp = tm_to_time_t(&tm);
880 if (*timestamp == -1)
881 return -1;
883 if (*offset == -1) {
884 time_t temp_time;
886 /* gmtime_r() in match_digit() may have clobbered it */
887 tm.tm_isdst = -1;
888 temp_time = mktime(&tm);
889 if ((time_t)*timestamp > temp_time) {
890 *offset = ((time_t)*timestamp - temp_time) / 60;
891 } else {
892 *offset = -(int)((temp_time - (time_t)*timestamp) / 60);
896 if (!tm_gmt)
897 *timestamp -= *offset * 60;
898 return 0; /* success */
901 int parse_expiry_date(const char *date, timestamp_t *timestamp)
903 int errors = 0;
905 if (!strcmp(date, "never") || !strcmp(date, "false"))
906 *timestamp = 0;
907 else if (!strcmp(date, "all") || !strcmp(date, "now"))
909 * We take over "now" here, which usually translates
910 * to the current timestamp. This is because the user
911 * really means to expire everything she has done in
912 * the past, and by definition reflogs are the record
913 * of the past, and there is nothing from the future
914 * to be kept.
916 *timestamp = TIME_MAX;
917 else
918 *timestamp = approxidate_careful(date, &errors);
920 return errors;
923 int parse_date(const char *date, struct strbuf *result)
925 timestamp_t timestamp;
926 int offset;
927 if (parse_date_basic(date, &timestamp, &offset))
928 return -1;
929 date_string(timestamp, offset, result);
930 return 0;
933 static enum date_mode_type parse_date_type(const char *format, const char **end)
935 if (skip_prefix(format, "relative", end))
936 return DATE_RELATIVE;
937 if (skip_prefix(format, "iso8601-strict", end) ||
938 skip_prefix(format, "iso-strict", end))
939 return DATE_ISO8601_STRICT;
940 if (skip_prefix(format, "iso8601", end) ||
941 skip_prefix(format, "iso", end))
942 return DATE_ISO8601;
943 if (skip_prefix(format, "rfc2822", end) ||
944 skip_prefix(format, "rfc", end))
945 return DATE_RFC2822;
946 if (skip_prefix(format, "short", end))
947 return DATE_SHORT;
948 if (skip_prefix(format, "default", end))
949 return DATE_NORMAL;
950 if (skip_prefix(format, "human", end))
951 return DATE_HUMAN;
952 if (skip_prefix(format, "raw", end))
953 return DATE_RAW;
954 if (skip_prefix(format, "unix", end))
955 return DATE_UNIX;
956 if (skip_prefix(format, "format", end))
957 return DATE_STRFTIME;
959 * Please update $__git_log_date_formats in
960 * git-completion.bash when you add new formats.
963 die("unknown date format %s", format);
966 void parse_date_format(const char *format, struct date_mode *mode)
968 const char *p;
970 /* "auto:foo" is "if tty/pager, then foo, otherwise normal" */
971 if (skip_prefix(format, "auto:", &p)) {
972 if (isatty(1) || pager_in_use())
973 format = p;
974 else
975 format = "default";
978 /* historical alias */
979 if (!strcmp(format, "local"))
980 format = "default-local";
982 mode->type = parse_date_type(format, &p);
983 mode->local = 0;
985 if (skip_prefix(p, "-local", &p))
986 mode->local = 1;
988 if (mode->type == DATE_STRFTIME) {
989 if (!skip_prefix(p, ":", &p))
990 die("date format missing colon separator: %s", format);
991 mode->strftime_fmt = xstrdup(p);
992 } else if (*p)
993 die("unknown date format %s", format);
996 void datestamp(struct strbuf *out)
998 time_t now;
999 int offset;
1000 struct tm tm = { 0 };
1002 time(&now);
1004 offset = tm_to_time_t(localtime_r(&now, &tm)) - now;
1005 offset /= 60;
1007 date_string(now, offset, out);
1011 * Relative time update (eg "2 days ago"). If we haven't set the time
1012 * yet, we need to set it from current time.
1014 static time_t update_tm(struct tm *tm, struct tm *now, time_t sec)
1016 time_t n;
1018 if (tm->tm_mday < 0)
1019 tm->tm_mday = now->tm_mday;
1020 if (tm->tm_mon < 0)
1021 tm->tm_mon = now->tm_mon;
1022 if (tm->tm_year < 0) {
1023 tm->tm_year = now->tm_year;
1024 if (tm->tm_mon > now->tm_mon)
1025 tm->tm_year--;
1028 n = mktime(tm) - sec;
1029 localtime_r(&n, tm);
1030 return n;
1034 * Do we have a pending number at the end, or when
1035 * we see a new one? Let's assume it's a month day,
1036 * as in "Dec 6, 1992"
1038 static void pending_number(struct tm *tm, int *num)
1040 int number = *num;
1042 if (number) {
1043 *num = 0;
1044 if (tm->tm_mday < 0 && number < 32)
1045 tm->tm_mday = number;
1046 else if (tm->tm_mon < 0 && number < 13)
1047 tm->tm_mon = number-1;
1048 else if (tm->tm_year < 0) {
1049 if (number > 1969 && number < 2100)
1050 tm->tm_year = number - 1900;
1051 else if (number > 69 && number < 100)
1052 tm->tm_year = number;
1053 else if (number < 38)
1054 tm->tm_year = 100 + number;
1055 /* We screw up for number = 00 ? */
1060 static void date_now(struct tm *tm, struct tm *now, int *num)
1062 *num = 0;
1063 update_tm(tm, now, 0);
1066 static void date_yesterday(struct tm *tm, struct tm *now, int *num)
1068 *num = 0;
1069 update_tm(tm, now, 24*60*60);
1072 static void date_time(struct tm *tm, struct tm *now, int hour)
1074 if (tm->tm_hour < hour)
1075 update_tm(tm, now, 24*60*60);
1076 tm->tm_hour = hour;
1077 tm->tm_min = 0;
1078 tm->tm_sec = 0;
1081 static void date_midnight(struct tm *tm, struct tm *now, int *num)
1083 pending_number(tm, num);
1084 date_time(tm, now, 0);
1087 static void date_noon(struct tm *tm, struct tm *now, int *num)
1089 pending_number(tm, num);
1090 date_time(tm, now, 12);
1093 static void date_tea(struct tm *tm, struct tm *now, int *num)
1095 pending_number(tm, num);
1096 date_time(tm, now, 17);
1099 static void date_pm(struct tm *tm, struct tm *now, int *num)
1101 int hour, n = *num;
1102 *num = 0;
1104 hour = tm->tm_hour;
1105 if (n) {
1106 hour = n;
1107 tm->tm_min = 0;
1108 tm->tm_sec = 0;
1110 tm->tm_hour = (hour % 12) + 12;
1113 static void date_am(struct tm *tm, struct tm *now, int *num)
1115 int hour, n = *num;
1116 *num = 0;
1118 hour = tm->tm_hour;
1119 if (n) {
1120 hour = n;
1121 tm->tm_min = 0;
1122 tm->tm_sec = 0;
1124 tm->tm_hour = (hour % 12);
1127 static void date_never(struct tm *tm, struct tm *now, int *num)
1129 time_t n = 0;
1130 localtime_r(&n, tm);
1131 *num = 0;
1134 static const struct special {
1135 const char *name;
1136 void (*fn)(struct tm *, struct tm *, int *);
1137 } special[] = {
1138 { "yesterday", date_yesterday },
1139 { "noon", date_noon },
1140 { "midnight", date_midnight },
1141 { "tea", date_tea },
1142 { "PM", date_pm },
1143 { "AM", date_am },
1144 { "never", date_never },
1145 { "now", date_now },
1146 { NULL }
1149 static const char *number_name[] = {
1150 "zero", "one", "two", "three", "four",
1151 "five", "six", "seven", "eight", "nine", "ten",
1154 static const struct typelen {
1155 const char *type;
1156 int length;
1157 } typelen[] = {
1158 { "seconds", 1 },
1159 { "minutes", 60 },
1160 { "hours", 60*60 },
1161 { "days", 24*60*60 },
1162 { "weeks", 7*24*60*60 },
1163 { NULL }
1166 static const char *approxidate_alpha(const char *date, struct tm *tm, struct tm *now, int *num, int *touched)
1168 const struct typelen *tl;
1169 const struct special *s;
1170 const char *end = date;
1171 int i;
1173 while (isalpha(*++end))
1176 for (i = 0; i < 12; i++) {
1177 int match = match_string(date, month_names[i]);
1178 if (match >= 3) {
1179 tm->tm_mon = i;
1180 *touched = 1;
1181 return end;
1185 for (s = special; s->name; s++) {
1186 int len = strlen(s->name);
1187 if (match_string(date, s->name) == len) {
1188 s->fn(tm, now, num);
1189 *touched = 1;
1190 return end;
1194 if (!*num) {
1195 for (i = 1; i < 11; i++) {
1196 int len = strlen(number_name[i]);
1197 if (match_string(date, number_name[i]) == len) {
1198 *num = i;
1199 *touched = 1;
1200 return end;
1203 if (match_string(date, "last") == 4) {
1204 *num = 1;
1205 *touched = 1;
1207 return end;
1210 tl = typelen;
1211 while (tl->type) {
1212 int len = strlen(tl->type);
1213 if (match_string(date, tl->type) >= len-1) {
1214 update_tm(tm, now, tl->length * *num);
1215 *num = 0;
1216 *touched = 1;
1217 return end;
1219 tl++;
1222 for (i = 0; i < 7; i++) {
1223 int match = match_string(date, weekday_names[i]);
1224 if (match >= 3) {
1225 int diff, n = *num -1;
1226 *num = 0;
1228 diff = tm->tm_wday - i;
1229 if (diff <= 0)
1230 n++;
1231 diff += 7*n;
1233 update_tm(tm, now, diff * 24 * 60 * 60);
1234 *touched = 1;
1235 return end;
1239 if (match_string(date, "months") >= 5) {
1240 int n;
1241 update_tm(tm, now, 0); /* fill in date fields if needed */
1242 n = tm->tm_mon - *num;
1243 *num = 0;
1244 while (n < 0) {
1245 n += 12;
1246 tm->tm_year--;
1248 tm->tm_mon = n;
1249 *touched = 1;
1250 return end;
1253 if (match_string(date, "years") >= 4) {
1254 update_tm(tm, now, 0); /* fill in date fields if needed */
1255 tm->tm_year -= *num;
1256 *num = 0;
1257 *touched = 1;
1258 return end;
1261 return end;
1264 static const char *approxidate_digit(const char *date, struct tm *tm, int *num,
1265 time_t now)
1267 char *end;
1268 timestamp_t number = parse_timestamp(date, &end, 10);
1270 switch (*end) {
1271 case ':':
1272 case '.':
1273 case '/':
1274 case '-':
1275 if (isdigit(end[1])) {
1276 int match = match_multi_number(number, *end, date, end,
1277 tm, now);
1278 if (match)
1279 return date + match;
1283 /* Accept zero-padding only for small numbers ("Dec 02", never "Dec 0002") */
1284 if (date[0] != '0' || end - date <= 2)
1285 *num = number;
1286 return end;
1289 static timestamp_t approxidate_str(const char *date,
1290 const struct timeval *tv,
1291 int *error_ret)
1293 int number = 0;
1294 int touched = 0;
1295 struct tm tm, now;
1296 time_t time_sec;
1298 time_sec = tv->tv_sec;
1299 localtime_r(&time_sec, &tm);
1300 now = tm;
1302 tm.tm_year = -1;
1303 tm.tm_mon = -1;
1304 tm.tm_mday = -1;
1306 for (;;) {
1307 unsigned char c = *date;
1308 if (!c)
1309 break;
1310 date++;
1311 if (isdigit(c)) {
1312 pending_number(&tm, &number);
1313 date = approxidate_digit(date-1, &tm, &number, time_sec);
1314 touched = 1;
1315 continue;
1317 if (isalpha(c))
1318 date = approxidate_alpha(date-1, &tm, &now, &number, &touched);
1320 pending_number(&tm, &number);
1321 if (!touched)
1322 *error_ret = 1;
1323 return (timestamp_t)update_tm(&tm, &now, 0);
1326 timestamp_t approxidate_relative(const char *date)
1328 struct timeval tv;
1329 timestamp_t timestamp;
1330 int offset;
1331 int errors = 0;
1333 if (!parse_date_basic(date, &timestamp, &offset))
1334 return timestamp;
1336 get_time(&tv);
1337 return approxidate_str(date, (const struct timeval *) &tv, &errors);
1340 timestamp_t approxidate_careful(const char *date, int *error_ret)
1342 struct timeval tv;
1343 timestamp_t timestamp;
1344 int offset;
1345 int dummy = 0;
1346 if (!error_ret)
1347 error_ret = &dummy;
1349 if (!parse_date_basic(date, &timestamp, &offset)) {
1350 *error_ret = 0;
1351 return timestamp;
1354 get_time(&tv);
1355 return approxidate_str(date, &tv, error_ret);
1358 int date_overflows(timestamp_t t)
1360 time_t sys;
1362 /* If we overflowed our timestamp data type, that's bad... */
1363 if ((uintmax_t)t >= TIME_MAX)
1364 return 1;
1367 * ...but we also are going to feed the result to system
1368 * functions that expect time_t, which is often "signed long".
1369 * Make sure that we fit into time_t, as well.
1371 sys = t;
1372 return t != sys || (t < 1) != (sys < 1);