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-rw-r--r--date.c796
1 files changed, 796 insertions, 0 deletions
diff --git a/date.c b/date.c
new file mode 100644
index 0000000000..542c004c2e
--- /dev/null
+++ b/date.c
@@ -0,0 +1,796 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+
+#include "cache.h"
+
+static time_t my_mktime(struct tm *tm)
+{
+ static const int mdays[] = {
+ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
+ };
+ int year = tm->tm_year - 70;
+ int month = tm->tm_mon;
+ int day = tm->tm_mday;
+
+ if (year < 0 || year > 129) /* algo only works for 1970-2099 */
+ return -1;
+ if (month < 0 || month > 11) /* array bounds */
+ return -1;
+ if (month < 2 || (year + 2) % 4)
+ day--;
+ return (year * 365 + (year + 1) / 4 + mdays[month] + day) * 24*60*60UL +
+ tm->tm_hour * 60*60 + tm->tm_min * 60 + tm->tm_sec;
+}
+
+static const char *month_names[] = {
+ "January", "February", "March", "April", "May", "June",
+ "July", "August", "September", "October", "November", "December"
+};
+
+static const char *weekday_names[] = {
+ "Sundays", "Mondays", "Tuesdays", "Wednesdays", "Thursdays", "Fridays", "Saturdays"
+};
+
+static time_t gm_time_t(unsigned long time, int tz)
+{
+ int minutes;
+
+ minutes = tz < 0 ? -tz : tz;
+ minutes = (minutes / 100)*60 + (minutes % 100);
+ minutes = tz < 0 ? -minutes : minutes;
+ return time + minutes * 60;
+}
+
+/*
+ * The "tz" thing is passed in as this strange "decimal parse of tz"
+ * thing, which means that tz -0100 is passed in as the integer -100,
+ * even though it means "sixty minutes off"
+ */
+static struct tm *time_to_tm(unsigned long time, int tz)
+{
+ time_t t = gm_time_t(time, tz);
+ return gmtime(&t);
+}
+
+const char *show_date(unsigned long time, int tz, int relative)
+{
+ struct tm *tm;
+ static char timebuf[200];
+
+ if (relative) {
+ unsigned long diff;
+ struct timeval now;
+ gettimeofday(&now, NULL);
+ if (now.tv_sec < time)
+ return "in the future";
+ diff = now.tv_sec - time;
+ if (diff < 90) {
+ snprintf(timebuf, sizeof(timebuf), "%lu seconds ago", diff);
+ return timebuf;
+ }
+ /* Turn it into minutes */
+ diff = (diff + 30) / 60;
+ if (diff < 90) {
+ snprintf(timebuf, sizeof(timebuf), "%lu minutes ago", diff);
+ return timebuf;
+ }
+ /* Turn it into hours */
+ diff = (diff + 30) / 60;
+ if (diff < 36) {
+ snprintf(timebuf, sizeof(timebuf), "%lu hours ago", diff);
+ return timebuf;
+ }
+ /* We deal with number of days from here on */
+ diff = (diff + 12) / 24;
+ if (diff < 14) {
+ snprintf(timebuf, sizeof(timebuf), "%lu days ago", diff);
+ return timebuf;
+ }
+ /* Say weeks for the past 10 weeks or so */
+ if (diff < 70) {
+ snprintf(timebuf, sizeof(timebuf), "%lu weeks ago", (diff + 3) / 7);
+ return timebuf;
+ }
+ /* Say months for the past 12 months or so */
+ if (diff < 360) {
+ snprintf(timebuf, sizeof(timebuf), "%lu months ago", (diff + 15) / 30);
+ return timebuf;
+ }
+ /* Else fall back on absolute format.. */
+ }
+
+ tm = time_to_tm(time, tz);
+ if (!tm)
+ return NULL;
+ sprintf(timebuf, "%.3s %.3s %d %02d:%02d:%02d %d %+05d",
+ weekday_names[tm->tm_wday],
+ month_names[tm->tm_mon],
+ tm->tm_mday,
+ tm->tm_hour, tm->tm_min, tm->tm_sec,
+ tm->tm_year + 1900, tz);
+ return timebuf;
+}
+
+const char *show_rfc2822_date(unsigned long time, int tz)
+{
+ struct tm *tm;
+ static char timebuf[200];
+
+ tm = time_to_tm(time, tz);
+ if (!tm)
+ return NULL;
+ sprintf(timebuf, "%.3s, %d %.3s %d %02d:%02d:%02d %+05d",
+ weekday_names[tm->tm_wday], tm->tm_mday,
+ month_names[tm->tm_mon], tm->tm_year + 1900,
+ tm->tm_hour, tm->tm_min, tm->tm_sec, tz);
+ return timebuf;
+}
+
+/*
+ * Check these. And note how it doesn't do the summer-time conversion.
+ *
+ * In my world, it's always summer, and things are probably a bit off
+ * in other ways too.
+ */
+static const struct {
+ const char *name;
+ int offset;
+ int dst;
+} timezone_names[] = {
+ { "IDLW", -12, 0, }, /* International Date Line West */
+ { "NT", -11, 0, }, /* Nome */
+ { "CAT", -10, 0, }, /* Central Alaska */
+ { "HST", -10, 0, }, /* Hawaii Standard */
+ { "HDT", -10, 1, }, /* Hawaii Daylight */
+ { "YST", -9, 0, }, /* Yukon Standard */
+ { "YDT", -9, 1, }, /* Yukon Daylight */
+ { "PST", -8, 0, }, /* Pacific Standard */
+ { "PDT", -8, 1, }, /* Pacific Daylight */
+ { "MST", -7, 0, }, /* Mountain Standard */
+ { "MDT", -7, 1, }, /* Mountain Daylight */
+ { "CST", -6, 0, }, /* Central Standard */
+ { "CDT", -6, 1, }, /* Central Daylight */
+ { "EST", -5, 0, }, /* Eastern Standard */
+ { "EDT", -5, 1, }, /* Eastern Daylight */
+ { "AST", -3, 0, }, /* Atlantic Standard */
+ { "ADT", -3, 1, }, /* Atlantic Daylight */
+ { "WAT", -1, 0, }, /* West Africa */
+
+ { "GMT", 0, 0, }, /* Greenwich Mean */
+ { "UTC", 0, 0, }, /* Universal (Coordinated) */
+
+ { "WET", 0, 0, }, /* Western European */
+ { "BST", 0, 1, }, /* British Summer */
+ { "CET", +1, 0, }, /* Central European */
+ { "MET", +1, 0, }, /* Middle European */
+ { "MEWT", +1, 0, }, /* Middle European Winter */
+ { "MEST", +1, 1, }, /* Middle European Summer */
+ { "CEST", +1, 1, }, /* Central European Summer */
+ { "MESZ", +1, 1, }, /* Middle European Summer */
+ { "FWT", +1, 0, }, /* French Winter */
+ { "FST", +1, 1, }, /* French Summer */
+ { "EET", +2, 0, }, /* Eastern Europe, USSR Zone 1 */
+ { "EEST", +2, 1, }, /* Eastern European Daylight */
+ { "WAST", +7, 0, }, /* West Australian Standard */
+ { "WADT", +7, 1, }, /* West Australian Daylight */
+ { "CCT", +8, 0, }, /* China Coast, USSR Zone 7 */
+ { "JST", +9, 0, }, /* Japan Standard, USSR Zone 8 */
+ { "EAST", +10, 0, }, /* Eastern Australian Standard */
+ { "EADT", +10, 1, }, /* Eastern Australian Daylight */
+ { "GST", +10, 0, }, /* Guam Standard, USSR Zone 9 */
+ { "NZT", +11, 0, }, /* New Zealand */
+ { "NZST", +11, 0, }, /* New Zealand Standard */
+ { "NZDT", +11, 1, }, /* New Zealand Daylight */
+ { "IDLE", +12, 0, }, /* International Date Line East */
+};
+
+static int match_string(const char *date, const char *str)
+{
+ int i = 0;
+
+ for (i = 0; *date; date++, str++, i++) {
+ if (*date == *str)
+ continue;
+ if (toupper(*date) == toupper(*str))
+ continue;
+ if (!isalnum(*date))
+ break;
+ return 0;
+ }
+ return i;
+}
+
+static int skip_alpha(const char *date)
+{
+ int i = 0;
+ do {
+ i++;
+ } while (isalpha(date[i]));
+ return i;
+}
+
+/*
+* Parse month, weekday, or timezone name
+*/
+static int match_alpha(const char *date, struct tm *tm, int *offset)
+{
+ int i;
+
+ for (i = 0; i < 12; i++) {
+ int match = match_string(date, month_names[i]);
+ if (match >= 3) {
+ tm->tm_mon = i;
+ return match;
+ }
+ }
+
+ for (i = 0; i < 7; i++) {
+ int match = match_string(date, weekday_names[i]);
+ if (match >= 3) {
+ tm->tm_wday = i;
+ return match;
+ }
+ }
+
+ for (i = 0; i < ARRAY_SIZE(timezone_names); i++) {
+ int match = match_string(date, timezone_names[i].name);
+ if (match >= 3) {
+ int off = timezone_names[i].offset;
+
+ /* This is bogus, but we like summer */
+ off += timezone_names[i].dst;
+
+ /* Only use the tz name offset if we don't have anything better */
+ if (*offset == -1)
+ *offset = 60*off;
+
+ return match;
+ }
+ }
+
+ if (match_string(date, "PM") == 2) {
+ tm->tm_hour = (tm->tm_hour % 12) + 12;
+ return 2;
+ }
+
+ if (match_string(date, "AM") == 2) {
+ tm->tm_hour = (tm->tm_hour % 12) + 0;
+ return 2;
+ }
+
+ /* BAD CRAP */
+ return skip_alpha(date);
+}
+
+static int is_date(int year, int month, int day, struct tm *now_tm, time_t now, struct tm *tm)
+{
+ if (month > 0 && month < 13 && day > 0 && day < 32) {
+ struct tm check = *tm;
+ struct tm *r = (now_tm ? &check : tm);
+ time_t specified;
+
+ r->tm_mon = month - 1;
+ r->tm_mday = day;
+ if (year == -1) {
+ if (!now_tm)
+ return 1;
+ r->tm_year = now_tm->tm_year;
+ }
+ else if (year >= 1970 && year < 2100)
+ r->tm_year = year - 1900;
+ else if (year > 70 && year < 100)
+ r->tm_year = year;
+ else if (year < 38)
+ r->tm_year = year + 100;
+ else
+ return 0;
+ if (!now_tm)
+ return 1;
+
+ specified = my_mktime(r);
+
+ /* Be it commit time or author time, it does not make
+ * sense to specify timestamp way into the future. Make
+ * sure it is not later than ten days from now...
+ */
+ if (now + 10*24*3600 < specified)
+ return 0;
+ tm->tm_mon = r->tm_mon;
+ tm->tm_mday = r->tm_mday;
+ if (year != -1)
+ tm->tm_year = r->tm_year;
+ return 1;
+ }
+ return 0;
+}
+
+static int match_multi_number(unsigned long num, char c, const char *date, char *end, struct tm *tm)
+{
+ time_t now;
+ struct tm now_tm;
+ struct tm *refuse_future;
+ long num2, num3;
+
+ num2 = strtol(end+1, &end, 10);
+ num3 = -1;
+ if (*end == c && isdigit(end[1]))
+ num3 = strtol(end+1, &end, 10);
+
+ /* Time? Date? */
+ switch (c) {
+ case ':':
+ if (num3 < 0)
+ num3 = 0;
+ if (num < 25 && num2 >= 0 && num2 < 60 && num3 >= 0 && num3 <= 60) {
+ tm->tm_hour = num;
+ tm->tm_min = num2;
+ tm->tm_sec = num3;
+ break;
+ }
+ return 0;
+
+ case '-':
+ case '/':
+ case '.':
+ now = time(NULL);
+ refuse_future = NULL;
+ if (gmtime_r(&now, &now_tm))
+ refuse_future = &now_tm;
+
+ if (num > 70) {
+ /* yyyy-mm-dd? */
+ if (is_date(num, num2, num3, refuse_future, now, tm))
+ break;
+ /* yyyy-dd-mm? */
+ if (is_date(num, num3, num2, refuse_future, now, tm))
+ break;
+ }
+ /* Our eastern European friends say dd.mm.yy[yy]
+ * is the norm there, so giving precedence to
+ * mm/dd/yy[yy] form only when separator is not '.'
+ */
+ if (c != '.' &&
+ is_date(num3, num, num2, refuse_future, now, tm))
+ break;
+ /* European dd.mm.yy[yy] or funny US dd/mm/yy[yy] */
+ if (is_date(num3, num2, num, refuse_future, now, tm))
+ break;
+ /* Funny European mm.dd.yy */
+ if (c == '.' &&
+ is_date(num3, num, num2, refuse_future, now, tm))
+ break;
+ return 0;
+ }
+ return end - date;
+}
+
+/*
+ * We've seen a digit. Time? Year? Date?
+ */
+static int match_digit(const char *date, struct tm *tm, int *offset, int *tm_gmt)
+{
+ int n;
+ char *end;
+ unsigned long num;
+
+ num = strtoul(date, &end, 10);
+
+ /*
+ * Seconds since 1970? We trigger on that for anything after Jan 1, 2000
+ */
+ if (num > 946684800) {
+ time_t time = num;
+ if (gmtime_r(&time, tm)) {
+ *tm_gmt = 1;
+ return end - date;
+ }
+ }
+
+ /*
+ * Check for special formats: num[-.:/]num[same]num
+ */
+ switch (*end) {
+ case ':':
+ case '.':
+ case '/':
+ case '-':
+ if (isdigit(end[1])) {
+ int match = match_multi_number(num, *end, date, end, tm);
+ if (match)
+ return match;
+ }
+ }
+
+ /*
+ * None of the special formats? Try to guess what
+ * the number meant. We use the number of digits
+ * to make a more educated guess..
+ */
+ n = 0;
+ do {
+ n++;
+ } while (isdigit(date[n]));
+
+ /* Four-digit year or a timezone? */
+ if (n == 4) {
+ if (num <= 1400 && *offset == -1) {
+ unsigned int minutes = num % 100;
+ unsigned int hours = num / 100;
+ *offset = hours*60 + minutes;
+ } else if (num > 1900 && num < 2100)
+ tm->tm_year = num - 1900;
+ return n;
+ }
+
+ /*
+ * NOTE! We will give precedence to day-of-month over month or
+ * year numbers in the 1-12 range. So 05 is always "mday 5",
+ * unless we already have a mday..
+ *
+ * IOW, 01 Apr 05 parses as "April 1st, 2005".
+ */
+ if (num > 0 && num < 32 && tm->tm_mday < 0) {
+ tm->tm_mday = num;
+ return n;
+ }
+
+ /* Two-digit year? */
+ if (n == 2 && tm->tm_year < 0) {
+ if (num < 10 && tm->tm_mday >= 0) {
+ tm->tm_year = num + 100;
+ return n;
+ }
+ if (num >= 70) {
+ tm->tm_year = num;
+ return n;
+ }
+ }
+
+ if (num > 0 && num < 32) {
+ tm->tm_mday = num;
+ } else if (num > 1900) {
+ tm->tm_year = num - 1900;
+ } else if (num > 70) {
+ tm->tm_year = num;
+ } else if (num > 0 && num < 13) {
+ tm->tm_mon = num-1;
+ }
+
+ return n;
+}
+
+static int match_tz(const char *date, int *offp)
+{
+ char *end;
+ int offset = strtoul(date+1, &end, 10);
+ int min, hour;
+ int n = end - date - 1;
+
+ min = offset % 100;
+ hour = offset / 100;
+
+ /*
+ * Don't accept any random crap.. At least 3 digits, and
+ * a valid minute. We might want to check that the minutes
+ * are divisible by 30 or something too.
+ */
+ if (min < 60 && n > 2) {
+ offset = hour*60+min;
+ if (*date == '-')
+ offset = -offset;
+
+ *offp = offset;
+ }
+ return end - date;
+}
+
+static int date_string(unsigned long date, int offset, char *buf, int len)
+{
+ int sign = '+';
+
+ if (offset < 0) {
+ offset = -offset;
+ sign = '-';
+ }
+ return snprintf(buf, len, "%lu %c%02d%02d", date, sign, offset / 60, offset % 60);
+}
+
+/* Gr. strptime is crap for this; it doesn't have a way to require RFC2822
+ (i.e. English) day/month names, and it doesn't work correctly with %z. */
+int parse_date(const char *date, char *result, int maxlen)
+{
+ struct tm tm;
+ int offset, tm_gmt;
+ time_t then;
+
+ memset(&tm, 0, sizeof(tm));
+ tm.tm_year = -1;
+ tm.tm_mon = -1;
+ tm.tm_mday = -1;
+ tm.tm_isdst = -1;
+ offset = -1;
+ tm_gmt = 0;
+
+ for (;;) {
+ int match = 0;
+ unsigned char c = *date;
+
+ /* Stop at end of string or newline */
+ if (!c || c == '\n')
+ break;
+
+ if (isalpha(c))
+ match = match_alpha(date, &tm, &offset);
+ else if (isdigit(c))
+ match = match_digit(date, &tm, &offset, &tm_gmt);
+ else if ((c == '-' || c == '+') && isdigit(date[1]))
+ match = match_tz(date, &offset);
+
+ if (!match) {
+ /* BAD CRAP */
+ match = 1;
+ }
+
+ date += match;
+ }
+
+ /* mktime uses local timezone */
+ then = my_mktime(&tm);
+ if (offset == -1)
+ offset = (then - mktime(&tm)) / 60;
+
+ if (then == -1)
+ return -1;
+
+ if (!tm_gmt)
+ then -= offset * 60;
+ return date_string(then, offset, result, maxlen);
+}
+
+void datestamp(char *buf, int bufsize)
+{
+ time_t now;
+ int offset;
+
+ time(&now);
+
+ offset = my_mktime(localtime(&now)) - now;
+ offset /= 60;
+
+ date_string(now, offset, buf, bufsize);
+}
+
+static void update_tm(struct tm *tm, unsigned long sec)
+{
+ time_t n = mktime(tm) - sec;
+ localtime_r(&n, tm);
+}
+
+static void date_yesterday(struct tm *tm, int *num)
+{
+ update_tm(tm, 24*60*60);
+}
+
+static void date_time(struct tm *tm, int hour)
+{
+ if (tm->tm_hour < hour)
+ date_yesterday(tm, NULL);
+ tm->tm_hour = hour;
+ tm->tm_min = 0;
+ tm->tm_sec = 0;
+}
+
+static void date_midnight(struct tm *tm, int *num)
+{
+ date_time(tm, 0);
+}
+
+static void date_noon(struct tm *tm, int *num)
+{
+ date_time(tm, 12);
+}
+
+static void date_tea(struct tm *tm, int *num)
+{
+ date_time(tm, 17);
+}
+
+static void date_pm(struct tm *tm, int *num)
+{
+ int hour, n = *num;
+ *num = 0;
+
+ hour = tm->tm_hour;
+ if (n) {
+ hour = n;
+ tm->tm_min = 0;
+ tm->tm_sec = 0;
+ }
+ tm->tm_hour = (hour % 12) + 12;
+}
+
+static void date_am(struct tm *tm, int *num)
+{
+ int hour, n = *num;
+ *num = 0;
+
+ hour = tm->tm_hour;
+ if (n) {
+ hour = n;
+ tm->tm_min = 0;
+ tm->tm_sec = 0;
+ }
+ tm->tm_hour = (hour % 12);
+}
+
+static const struct special {
+ const char *name;
+ void (*fn)(struct tm *, int *);
+} special[] = {
+ { "yesterday", date_yesterday },
+ { "noon", date_noon },
+ { "midnight", date_midnight },
+ { "tea", date_tea },
+ { "PM", date_pm },
+ { "AM", date_am },
+ { NULL }
+};
+
+static const char *number_name[] = {
+ "zero", "one", "two", "three", "four",
+ "five", "six", "seven", "eight", "nine", "ten",
+};
+
+static const struct typelen {
+ const char *type;
+ int length;
+} typelen[] = {
+ { "seconds", 1 },
+ { "minutes", 60 },
+ { "hours", 60*60 },
+ { "days", 24*60*60 },
+ { "weeks", 7*24*60*60 },
+ { NULL }
+};
+
+static const char *approxidate_alpha(const char *date, struct tm *tm, int *num)
+{
+ const struct typelen *tl;
+ const struct special *s;
+ const char *end = date;
+ int i;
+
+ while (isalpha(*++end));
+ ;
+
+ for (i = 0; i < 12; i++) {
+ int match = match_string(date, month_names[i]);
+ if (match >= 3) {
+ tm->tm_mon = i;
+ return end;
+ }
+ }
+
+ for (s = special; s->name; s++) {
+ int len = strlen(s->name);
+ if (match_string(date, s->name) == len) {
+ s->fn(tm, num);
+ return end;
+ }
+ }
+
+ if (!*num) {
+ for (i = 1; i < 11; i++) {
+ int len = strlen(number_name[i]);
+ if (match_string(date, number_name[i]) == len) {
+ *num = i;
+ return end;
+ }
+ }
+ if (match_string(date, "last") == 4)
+ *num = 1;
+ return end;
+ }
+
+ tl = typelen;
+ while (tl->type) {
+ int len = strlen(tl->type);
+ if (match_string(date, tl->type) >= len-1) {
+ update_tm(tm, tl->length * *num);
+ *num = 0;
+ return end;
+ }
+ tl++;
+ }
+
+ for (i = 0; i < 7; i++) {
+ int match = match_string(date, weekday_names[i]);
+ if (match >= 3) {
+ int diff, n = *num -1;
+ *num = 0;
+
+ diff = tm->tm_wday - i;
+ if (diff <= 0)
+ n++;
+ diff += 7*n;
+
+ update_tm(tm, diff * 24 * 60 * 60);
+ return end;
+ }
+ }
+
+ if (match_string(date, "months") >= 5) {
+ int n = tm->tm_mon - *num;
+ *num = 0;
+ while (n < 0) {
+ n += 12;
+ tm->tm_year--;
+ }
+ tm->tm_mon = n;
+ return end;
+ }
+
+ if (match_string(date, "years") >= 4) {
+ tm->tm_year -= *num;
+ *num = 0;
+ return end;
+ }
+
+ return end;
+}
+
+static const char *approxidate_digit(const char *date, struct tm *tm, int *num)
+{
+ char *end;
+ unsigned long number = strtoul(date, &end, 10);
+
+ switch (*end) {
+ case ':':
+ case '.':
+ case '/':
+ case '-':
+ if (isdigit(end[1])) {
+ int match = match_multi_number(number, *end, date, end, tm);
+ if (match)
+ return date + match;
+ }
+ }
+
+ *num = number;
+ return end;
+}
+
+unsigned long approxidate(const char *date)
+{
+ int number = 0;
+ struct tm tm, now;
+ struct timeval tv;
+ char buffer[50];
+
+ if (parse_date(date, buffer, sizeof(buffer)) > 0)
+ return strtoul(buffer, NULL, 10);
+
+ gettimeofday(&tv, NULL);
+ localtime_r(&tv.tv_sec, &tm);
+ now = tm;
+ for (;;) {
+ unsigned char c = *date;
+ if (!c)
+ break;
+ date++;
+ if (isdigit(c)) {
+ date = approxidate_digit(date-1, &tm, &number);
+ continue;
+ }
+ if (isalpha(c))
+ date = approxidate_alpha(date-1, &tm, &number);
+ }
+ if (number > 0 && number < 32)
+ tm.tm_mday = number;
+ if (tm.tm_mon > now.tm_mon && tm.tm_year == now.tm_year)
+ tm.tm_year--;
+ return mktime(&tm);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-20 14:10:39 +0000