git/date.c
Junio C Hamano 116eb3abfe parse_date(): allow ancient git-timestamp
The date-time parser parses out a human-readble datestring piece by
piece, so that it could even parse a string in a rather strange
notation like 'noon november 11, 2005', but restricts itself from
parsing strings in "<seconds since epoch> <timezone>" format only
for reasonably new timestamps (like 1974 or newer) with 10 or more
digits. This is to prevent a string like "20100917" from getting
interpreted as seconds since epoch (we want to treat it as September
17, 2010 instead) while doing so.

The same codepath is used to read back the timestamp that we have
already recorded in the headers of commit and tag objects; because
of this, such a commit with timestamp "0 +0000" cannot be rebased or
amended very easily.

Teach parse_date() codepath to special case a string of the form
"<digits> +<4-digits>" to work this issue around, but require that
there is no other cruft around the string when parsing a timestamp
of this format for safety.

Note that this has a slight backward incompatibility implications.

If somebody writes "git commit --date='20100917 +0900'" and wants it
to mean a timestamp in September 2010 in Japan, this change will
break such a use case.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-03 23:11:32 -08:00

1058 lines
23 KiB
C

/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.h"
/*
* This is like mktime, but without normalization of tm_wday and tm_yday.
*/
static time_t tm_to_time_t(const 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--;
if (tm->tm_hour < 0 || tm->tm_min < 0 || tm->tm_sec < 0)
return -1;
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);
}
/*
* What value of "tz" was in effect back then at "time" in the
* local timezone?
*/
static int local_tzoffset(unsigned long time)
{
time_t t, t_local;
struct tm tm;
int offset, eastwest;
t = time;
localtime_r(&t, &tm);
t_local = tm_to_time_t(&tm);
if (t_local < t) {
eastwest = -1;
offset = t - t_local;
} else {
eastwest = 1;
offset = t_local - t;
}
offset /= 60; /* in minutes */
offset = (offset % 60) + ((offset / 60) * 100);
return offset * eastwest;
}
const char *show_date_relative(unsigned long time, int tz,
const struct timeval *now,
char *timebuf,
size_t timebuf_size)
{
unsigned long diff;
if (now->tv_sec < time)
return "in the future";
diff = now->tv_sec - time;
if (diff < 90) {
snprintf(timebuf, timebuf_size, "%lu seconds ago", diff);
return timebuf;
}
/* Turn it into minutes */
diff = (diff + 30) / 60;
if (diff < 90) {
snprintf(timebuf, timebuf_size, "%lu minutes ago", diff);
return timebuf;
}
/* Turn it into hours */
diff = (diff + 30) / 60;
if (diff < 36) {
snprintf(timebuf, timebuf_size, "%lu hours ago", diff);
return timebuf;
}
/* We deal with number of days from here on */
diff = (diff + 12) / 24;
if (diff < 14) {
snprintf(timebuf, timebuf_size, "%lu days ago", diff);
return timebuf;
}
/* Say weeks for the past 10 weeks or so */
if (diff < 70) {
snprintf(timebuf, timebuf_size, "%lu weeks ago", (diff + 3) / 7);
return timebuf;
}
/* Say months for the past 12 months or so */
if (diff < 365) {
snprintf(timebuf, timebuf_size, "%lu months ago", (diff + 15) / 30);
return timebuf;
}
/* Give years and months for 5 years or so */
if (diff < 1825) {
unsigned long totalmonths = (diff * 12 * 2 + 365) / (365 * 2);
unsigned long years = totalmonths / 12;
unsigned long months = totalmonths % 12;
int n;
n = snprintf(timebuf, timebuf_size, "%lu year%s",
years, (years > 1 ? "s" : ""));
if (months)
snprintf(timebuf + n, timebuf_size - n,
", %lu month%s ago",
months, (months > 1 ? "s" : ""));
else
snprintf(timebuf + n, timebuf_size - n, " ago");
return timebuf;
}
/* Otherwise, just years. Centuries is probably overkill. */
snprintf(timebuf, timebuf_size, "%lu years ago", (diff + 183) / 365);
return timebuf;
}
const char *show_date(unsigned long time, int tz, enum date_mode mode)
{
struct tm *tm;
static char timebuf[200];
if (mode == DATE_RAW) {
snprintf(timebuf, sizeof(timebuf), "%lu %+05d", time, tz);
return timebuf;
}
if (mode == DATE_RELATIVE) {
struct timeval now;
gettimeofday(&now, NULL);
return show_date_relative(time, tz, &now,
timebuf, sizeof(timebuf));
}
if (mode == DATE_LOCAL)
tz = local_tzoffset(time);
tm = time_to_tm(time, tz);
if (!tm)
return NULL;
if (mode == DATE_SHORT)
sprintf(timebuf, "%04d-%02d-%02d", tm->tm_year + 1900,
tm->tm_mon + 1, tm->tm_mday);
else if (mode == DATE_ISO8601)
sprintf(timebuf, "%04d-%02d-%02d %02d:%02d:%02d %+05d",
tm->tm_year + 1900,
tm->tm_mon + 1,
tm->tm_mday,
tm->tm_hour, tm->tm_min, tm->tm_sec,
tz);
else if (mode == DATE_RFC2822)
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);
else
sprintf(timebuf, "%.3s %.3s %d %02d:%02d:%02d %d%c%+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,
(mode == DATE_LOCAL) ? 0 : ' ',
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) */
{ "Z", 0, 0, }, /* Zulu, alias for UTC */
{ "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", +12, 0, }, /* New Zealand */
{ "NZST", +12, 0, }, /* New Zealand Standard */
{ "NZDT", +12, 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 || match == strlen(timezone_names[i].name)) {
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 = tm_to_time_t(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;
}
/*
* Have we filled in any part of the time/date yet?
* We just do a binary 'and' to see if the sign bit
* is set in all the values.
*/
static inline int nodate(struct tm *tm)
{
return (tm->tm_year &
tm->tm_mon &
tm->tm_mday &
tm->tm_hour &
tm->tm_min &
tm->tm_sec) < 0;
}
/*
* 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 any numbers with
* more than 8 digits. This is because we don't want to rule out
* numbers like 20070606 as a YYYYMMDD date.
*/
if (num >= 100000000 && nodate(tm)) {
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;
}
/*
* Ignore lots of numerals. We took care of 4-digit years above.
* Days or months must be one or two digits.
*/
if (n > 2)
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 < 13 && tm->tm_mon < 0)
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);
}
/*
* Parse a string like "0 +0000" as ancient timestamp near epoch, but
* only when it appears not as part of any other string.
*/
static int match_object_header_date(const char *date, unsigned long *timestamp, int *offset)
{
char *end;
unsigned long stamp;
int ofs;
if (*date < '0' || '9' <= *date)
return -1;
stamp = strtoul(date, &end, 10);
if (*end != ' ' || stamp == ULONG_MAX || (end[1] != '+' && end[1] != '-'))
return -1;
date = end + 2;
ofs = strtol(date, &end, 10);
if ((*end != '\0' && (*end != '\n')) || end != date + 4)
return -1;
ofs = (ofs / 100) * 60 + (ofs % 100);
if (date[-1] == '-')
ofs = -ofs;
*timestamp = stamp;
*offset = ofs;
return 0;
}
/* 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_basic(const char *date, unsigned long *timestamp, int *offset)
{
struct tm tm;
int tm_gmt;
unsigned long dummy_timestamp;
int dummy_offset;
if (!timestamp)
timestamp = &dummy_timestamp;
if (!offset)
offset = &dummy_offset;
memset(&tm, 0, sizeof(tm));
tm.tm_year = -1;
tm.tm_mon = -1;
tm.tm_mday = -1;
tm.tm_isdst = -1;
tm.tm_hour = -1;
tm.tm_min = -1;
tm.tm_sec = -1;
*offset = -1;
tm_gmt = 0;
if (!match_object_header_date(date, timestamp, offset))
return 0; /* success */
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 */
*timestamp = tm_to_time_t(&tm);
if (*offset == -1)
*offset = ((time_t)*timestamp - mktime(&tm)) / 60;
if (*timestamp == -1)
return -1;
if (!tm_gmt)
*timestamp -= *offset * 60;
return 0; /* success */
}
int parse_date(const char *date, char *result, int maxlen)
{
unsigned long timestamp;
int offset;
if (parse_date_basic(date, &timestamp, &offset))
return -1;
return date_string(timestamp, offset, result, maxlen);
}
enum date_mode parse_date_format(const char *format)
{
if (!strcmp(format, "relative"))
return DATE_RELATIVE;
else if (!strcmp(format, "iso8601") ||
!strcmp(format, "iso"))
return DATE_ISO8601;
else if (!strcmp(format, "rfc2822") ||
!strcmp(format, "rfc"))
return DATE_RFC2822;
else if (!strcmp(format, "short"))
return DATE_SHORT;
else if (!strcmp(format, "local"))
return DATE_LOCAL;
else if (!strcmp(format, "default"))
return DATE_NORMAL;
else if (!strcmp(format, "raw"))
return DATE_RAW;
else
die("unknown date format %s", format);
}
void datestamp(char *buf, int bufsize)
{
time_t now;
int offset;
time(&now);
offset = tm_to_time_t(localtime(&now)) - now;
offset /= 60;
date_string(now, offset, buf, bufsize);
}
/*
* Relative time update (eg "2 days ago"). If we haven't set the time
* yet, we need to set it from current time.
*/
static unsigned long update_tm(struct tm *tm, struct tm *now, unsigned long sec)
{
time_t n;
if (tm->tm_mday < 0)
tm->tm_mday = now->tm_mday;
if (tm->tm_mon < 0)
tm->tm_mon = now->tm_mon;
if (tm->tm_year < 0) {
tm->tm_year = now->tm_year;
if (tm->tm_mon > now->tm_mon)
tm->tm_year--;
}
n = mktime(tm) - sec;
localtime_r(&n, tm);
return n;
}
static void date_now(struct tm *tm, struct tm *now, int *num)
{
update_tm(tm, now, 0);
}
static void date_yesterday(struct tm *tm, struct tm *now, int *num)
{
update_tm(tm, now, 24*60*60);
}
static void date_time(struct tm *tm, struct tm *now, int hour)
{
if (tm->tm_hour < hour)
date_yesterday(tm, now, NULL);
tm->tm_hour = hour;
tm->tm_min = 0;
tm->tm_sec = 0;
}
static void date_midnight(struct tm *tm, struct tm *now, int *num)
{
date_time(tm, now, 0);
}
static void date_noon(struct tm *tm, struct tm *now, int *num)
{
date_time(tm, now, 12);
}
static void date_tea(struct tm *tm, struct tm *now, int *num)
{
date_time(tm, now, 17);
}
static void date_pm(struct tm *tm, struct tm *now, 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, struct tm *now, 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 void date_never(struct tm *tm, struct tm *now, int *num)
{
time_t n = 0;
localtime_r(&n, tm);
}
static const struct special {
const char *name;
void (*fn)(struct tm *, struct tm *, int *);
} special[] = {
{ "yesterday", date_yesterday },
{ "noon", date_noon },
{ "midnight", date_midnight },
{ "tea", date_tea },
{ "PM", date_pm },
{ "AM", date_am },
{ "never", date_never },
{ "now", date_now },
{ 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, struct tm *now, int *num, int *touched)
{
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;
*touched = 1;
return end;
}
}
for (s = special; s->name; s++) {
int len = strlen(s->name);
if (match_string(date, s->name) == len) {
s->fn(tm, now, num);
*touched = 1;
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;
*touched = 1;
return end;
}
}
if (match_string(date, "last") == 4) {
*num = 1;
*touched = 1;
}
return end;
}
tl = typelen;
while (tl->type) {
int len = strlen(tl->type);
if (match_string(date, tl->type) >= len-1) {
update_tm(tm, now, tl->length * *num);
*num = 0;
*touched = 1;
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, now, diff * 24 * 60 * 60);
*touched = 1;
return end;
}
}
if (match_string(date, "months") >= 5) {
int n;
update_tm(tm, now, 0); /* fill in date fields if needed */
n = tm->tm_mon - *num;
*num = 0;
while (n < 0) {
n += 12;
tm->tm_year--;
}
tm->tm_mon = n;
*touched = 1;
return end;
}
if (match_string(date, "years") >= 4) {
update_tm(tm, now, 0); /* fill in date fields if needed */
tm->tm_year -= *num;
*num = 0;
*touched = 1;
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;
}
}
/* Accept zero-padding only for small numbers ("Dec 02", never "Dec 0002") */
if (date[0] != '0' || end - date <= 2)
*num = number;
return end;
}
/*
* Do we have a pending number at the end, or when
* we see a new one? Let's assume it's a month day,
* as in "Dec 6, 1992"
*/
static void pending_number(struct tm *tm, int *num)
{
int number = *num;
if (number) {
*num = 0;
if (tm->tm_mday < 0 && number < 32)
tm->tm_mday = number;
else if (tm->tm_mon < 0 && number < 13)
tm->tm_mon = number-1;
else if (tm->tm_year < 0) {
if (number > 1969 && number < 2100)
tm->tm_year = number - 1900;
else if (number > 69 && number < 100)
tm->tm_year = number;
else if (number < 38)
tm->tm_year = 100 + number;
/* We screw up for number = 00 ? */
}
}
}
static unsigned long approxidate_str(const char *date,
const struct timeval *tv,
int *error_ret)
{
int number = 0;
int touched = 0;
struct tm tm, now;
time_t time_sec;
time_sec = tv->tv_sec;
localtime_r(&time_sec, &tm);
now = tm;
tm.tm_year = -1;
tm.tm_mon = -1;
tm.tm_mday = -1;
for (;;) {
unsigned char c = *date;
if (!c)
break;
date++;
if (isdigit(c)) {
pending_number(&tm, &number);
date = approxidate_digit(date-1, &tm, &number);
touched = 1;
continue;
}
if (isalpha(c))
date = approxidate_alpha(date-1, &tm, &now, &number, &touched);
}
pending_number(&tm, &number);
if (!touched)
*error_ret = 1;
return update_tm(&tm, &now, 0);
}
unsigned long approxidate_relative(const char *date, const struct timeval *tv)
{
unsigned long timestamp;
int offset;
int errors = 0;
if (!parse_date_basic(date, &timestamp, &offset))
return timestamp;
return approxidate_str(date, tv, &errors);
}
unsigned long approxidate_careful(const char *date, int *error_ret)
{
struct timeval tv;
unsigned long timestamp;
int offset;
int dummy = 0;
if (!error_ret)
error_ret = &dummy;
if (!parse_date_basic(date, &timestamp, &offset)) {
*error_ret = 0;
return timestamp;
}
gettimeofday(&tv, NULL);
return approxidate_str(date, &tv, error_ret);
}