2 * GIT - The information manager from hell
4 * Copyright (C) Linus Torvalds, 2005
13 static time_t my_mktime(struct tm *tm)
15 static const int mdays[] = {
16 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
18 int year = tm->tm_year - 70;
19 int month = tm->tm_mon;
20 int day = tm->tm_mday;
22 if (year < 0 || year > 129) /* algo only works for 1970-2099 */
24 if (month < 0 || month > 11) /* array bounds */
26 if (month < 2 || (year + 2) % 4)
28 return (year * 365 + (year + 1) / 4 + mdays[month] + day) * 24*60*60UL +
29 tm->tm_hour * 60*60 + tm->tm_min * 60 + tm->tm_sec;
32 static const char *month_names[] = {
33 "January", "February", "March", "April", "May", "June",
34 "July", "August", "September", "October", "November", "December"
37 static const char *weekday_names[] = {
38 "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
42 * Check these. And note how it doesn't do the summer-time conversion.
44 * In my world, it's always summer, and things are probably a bit off
51 } timezone_names[] = {
52 { "IDLW", -12, 0, }, /* International Date Line West */
53 { "NT", -11, 0, }, /* Nome */
54 { "CAT", -10, 0, }, /* Central Alaska */
55 { "HST", -10, 0, }, /* Hawaii Standard */
56 { "HDT", -10, 1, }, /* Hawaii Daylight */
57 { "YST", -9, 0, }, /* Yukon Standard */
58 { "YDT", -9, 1, }, /* Yukon Daylight */
59 { "PST", -8, 0, }, /* Pacific Standard */
60 { "PDT", -8, 1, }, /* Pacific Daylight */
61 { "MST", -7, 0, }, /* Mountain Standard */
62 { "MDT", -7, 1, }, /* Mountain Daylight */
63 { "CST", -6, 0, }, /* Central Standard */
64 { "CDT", -6, 1, }, /* Central Daylight */
65 { "EST", -5, 0, }, /* Eastern Standard */
66 { "EDT", -5, 1, }, /* Eastern Daylight */
67 { "AST", -3, 0, }, /* Atlantic Standard */
68 { "ADT", -3, 1, }, /* Atlantic Daylight */
69 { "WAT", -1, 0, }, /* West Africa */
71 { "GMT", 0, 0, }, /* Greenwich Mean */
72 { "UTC", 0, 0, }, /* Universal (Coordinated) */
74 { "WET", 0, 0, }, /* Western European */
75 { "BST", 0, 1, }, /* British Summer */
76 { "CET", +1, 0, }, /* Central European */
77 { "MET", +1, 0, }, /* Middle European */
78 { "MEWT", +1, 0, }, /* Middle European Winter */
79 { "MEST", +1, 1, }, /* Middle European Summer */
80 { "CEST", +1, 1, }, /* Central European Summer */
81 { "MESZ", +1, 1, }, /* Middle European Summer */
82 { "FWT", +1, 0, }, /* French Winter */
83 { "FST", +1, 1, }, /* French Summer */
84 { "EET", +2, 0, }, /* Eastern Europe, USSR Zone 1 */
85 { "EEST", +2, 1, }, /* Eastern European Daylight */
86 { "WAST", +7, 0, }, /* West Australian Standard */
87 { "WADT", +7, 1, }, /* West Australian Daylight */
88 { "CCT", +8, 0, }, /* China Coast, USSR Zone 7 */
89 { "JST", +9, 0, }, /* Japan Standard, USSR Zone 8 */
90 { "EAST", +10, 0, }, /* Eastern Australian Standard */
91 { "EADT", +10, 1, }, /* Eastern Australian Daylight */
92 { "GST", +10, 0, }, /* Guam Standard, USSR Zone 9 */
93 { "NZT", +11, 0, }, /* New Zealand */
94 { "NZST", +11, 0, }, /* New Zealand Standard */
95 { "NZDT", +11, 1, }, /* New Zealand Daylight */
96 { "IDLE", +12, 0, }, /* International Date Line East */
99 #define NR_TZ (sizeof(timezone_names) / sizeof(timezone_names[0]))
101 static int match_string(const char *date, const char *str)
105 for (i = 0; *date; date++, str++, i++) {
108 if (toupper(*date) == toupper(*str))
118 * Parse month, weekday, or timezone name
120 static int match_alpha(const char *date, struct tm *tm, int *offset)
124 for (i = 0; i < 12; i++) {
125 int match = match_string(date, month_names[i]);
132 for (i = 0; i < 7; i++) {
133 int match = match_string(date, weekday_names[i]);
140 for (i = 0; i < NR_TZ; i++) {
141 int match = match_string(date, timezone_names[i].name);
143 int off = timezone_names[i].offset;
145 /* This is bogus, but we like summer */
146 off += timezone_names[i].dst;
148 /* Only use the tz name offset if we don't have anything better */
160 static int match_digit(char *date, struct tm *tm, int *offset)
163 unsigned long num, num2, num3;
165 num = strtoul(date, &end, 10);
167 /* Time? num:num[:num] */
168 if (num < 24 && end[0] == ':' && isdigit(end[1])) {
170 num = strtoul(end+1, &end, 10);
173 if (end[0] == ':' && isdigit(end[1])) {
174 num = strtoul(end+1, &end, 10);
182 /* Year? Day of month? Numeric date-string?*/
186 if (num > 0 && num < 32) {
191 tm->tm_year = num - 1900;
202 if (num && num < 32 && isdigit(end[1])) {
203 num2 = strtoul(end+1, &end, 10);
204 if (!num2 || num2 > 31)
213 tm->tm_mon = num - 1;
215 if (*end == c && isdigit(end[1])) {
216 num3 = strtoul(end+1, &end, 10);
231 static int match_tz(char *date, int *offp)
234 int offset = strtoul(date+1, &end, 10);
240 offset = hour*60+min;
248 /* Gr. strptime is crap for this; it doesn't have a way to require RFC2822
249 (i.e. English) day/month names, and it doesn't work correctly with %z. */
250 void parse_date(char *date, char *result, int maxlen)
256 memset(&tm, 0, sizeof(tm));
265 unsigned char c = *date;
267 /* Stop at end of string or newline */
272 match = match_alpha(date, &tm, &offset);
274 match = match_digit(date, &tm, &offset);
275 else if ((c == '-' || c == '+') && isdigit(date[1]))
276 match = match_tz(date, &offset);
286 /* mktime uses local timezone */
287 then = my_mktime(&tm);
289 offset = (then - mktime(&tm)) / 60;
296 snprintf(result, maxlen, "%lu %+03d%02d", then, offset/60, offset % 60);
299 void datestamp(char *buf, int bufsize)
306 offset = my_mktime(localtime(&now)) - now;
309 snprintf(buf, bufsize, "%lu %+05d", now, offset/60*100 + offset%60);