X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=date.c;h=1c1917b4e8768b0046729e19505d6f1b0845a0d8;hb=cebff98dbe3fd6177337ae4d440b81ffed797608;hp=d3bae90677ca89f366439cf26596831c3fb847c5;hpb=92e2311b6c10bf1e4f3e1231d26a6e71d81c5f47;p=git.git

diff --git a/date.c b/date.c
index d3bae906..1c1917b4 100644
--- a/date.c
+++ b/date.c
@@ -4,11 +4,10 @@
  * Copyright (C) Linus Torvalds, 2005
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <ctype.h>
 #include <time.h>
+#include <sys/time.h>
+
+#include "cache.h"
 
 static time_t my_mktime(struct tm *tm)
 {
@@ -35,10 +34,38 @@ static const char *month_names[] = {
 };
 
 static const char *weekday_names[] = {
-	"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
+	"Sundays", "Mondays", "Tuesdays", "Wednesdays", "Thursdays", "Fridays", "Saturdays"
 };
 
 /*
+ * 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"
+ */
+const char *show_date(unsigned long time, int tz)
+{
+	struct tm *tm;
+	time_t t;
+	static char timebuf[200];
+	int minutes;
+
+	minutes = tz < 0 ? -tz : tz;
+	minutes = (minutes / 100)*60 + (minutes % 100);
+	minutes = tz < 0 ? -minutes : minutes;
+	t = time + minutes * 60;
+	tm = gmtime(&t);
+	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;
+}
+
+/*
  * 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
@@ -96,8 +123,6 @@ static const struct {
 	{ "IDLE", +12, 0, },	/* International Date Line East */
 };
 
-#define NR_TZ (sizeof(timezone_names) / sizeof(timezone_names[0]))
-	
 static int match_string(const char *date, const char *str)
 {
 	int i = 0;
@@ -114,6 +139,15 @@ static int match_string(const char *date, const char *str)
 	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
 */
@@ -137,7 +171,7 @@ static int match_alpha(const char *date, struct tm *tm, int *offset)
 		}
 	}
 
-	for (i = 0; i < NR_TZ; i++) {
+	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;
@@ -153,104 +187,220 @@ static int match_alpha(const char *date, struct tm *tm, int *offset)
 		}
 	}
 
+	if (match_string(date, "PM") == 2) {
+		if (tm->tm_hour > 0 && tm->tm_hour < 12)
+			tm->tm_hour += 12;
+		return 2;
+	}
+
 	/* BAD CRAP */
+	return skip_alpha(date);
+}
+
+static int is_date(int year, int month, int day, struct tm *tm)
+{
+	if (month > 0 && month < 13 && day > 0 && day < 32) {
+		if (year == -1) {
+			tm->tm_mon = month-1;
+			tm->tm_mday = day;
+			return 1;
+		}
+		if (year >= 1970 && year < 2100) {
+			year -= 1900;
+		} else if (year > 70 && year < 100) {
+			/* ok */
+		} else if (year < 38) {
+			year += 100;
+		} else
+			return 0;
+
+		tm->tm_mon = month-1;
+		tm->tm_mday = day;
+		tm->tm_year = year;
+		return 1;
+	}
 	return 0;
 }
 
-static int match_digit(char *date, struct tm *tm, int *offset)
+static int match_multi_number(unsigned long num, char c, const char *date, char *end, struct tm *tm)
+{
+	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 '/':
+		if (num > 70) {
+			/* yyyy-mm-dd? */
+			if (is_date(num, num2, num3, tm))
+				break;
+			/* yyyy-dd-mm? */
+			if (is_date(num, num3, num2, tm))
+				break;
+		}
+		/* mm/dd/yy ? */
+		if (is_date(num3, num2, num, tm))
+			break;
+		/* dd/mm/yy ? */
+		if (is_date(num3, num, num2, 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)
 {
-	char *end, c;
-	unsigned long num, num2, num3;
+	int n;
+	char *end;
+	unsigned long num;
 
 	num = strtoul(date, &end, 10);
 
-	/* Time? num:num[:num] */
-	if (num < 24 && end[0] == ':' && isdigit(end[1])) {
-		tm->tm_hour = num;
-		num = strtoul(end+1, &end, 10);
-		if (num < 60) {
-			tm->tm_min = num;
-			if (end[0] == ':' && isdigit(end[1])) {
-				num = strtoul(end+1, &end, 10);
-				if (num < 61)
-					tm->tm_sec = num;
-			}
+	/*
+	 * 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;
 		}
-		return end - date;
 	}
 
-	/* Year? Day of month? Numeric date-string?*/
-	c = *end;
-	switch (c) {
-	default:
-		if (num > 0 && num < 32) {
-			tm->tm_mday = num;
-			break;
+	/*
+	 * Check for special formats: num[:-/]num[same]num
+	 */
+	switch (*end) {
+	case ':':
+	case '/':
+	case '-':
+		if (isdigit(end[1])) {
+			int match = match_multi_number(num, *end, date, end, tm);
+			if (match)
+				return match;
 		}
-		if (num > 1900) {
+	}
+
+	/*
+	 * 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 <= 1200 && *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;
-			break;
+		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) {
+		if (num >= 70) {
 			tm->tm_year = num;
-			break;
+			return n;
 		}
-		break;
+	}
 
-	case '-':
-	case '/':
-		if (num && num < 32 && isdigit(end[1])) {
-			num2 = strtoul(end+1, &end, 10);
-			if (!num2 || num2 > 31)
-				break;
-			if (num > 12) {
-				if (num2 > 12)
-					break;
-				num3 = num;
-				num  = num2;
-				num2 = num3;
-			}
-			tm->tm_mon = num - 1;
-			tm->tm_mday = num2;
-			if (*end == c && isdigit(end[1])) {
-				num3 = strtoul(end+1, &end, 10);
-				if (num3 > 1900)
-					num3 -= 1900;
-				else if (num3 < 38)
-					num3 += 100;
-				tm->tm_year = num3;
-			}
-			break;
-		}
+	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 end - date;
-			
+	return n;
 }
 
-static int match_tz(char *date, int *offp)
+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;
 
-	offset = hour*60+min;
-	if (*date == '-')
-		offset = -offset;
-
-	*offp = offset;
+	/*
+	 * 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. */
-void parse_date(char *date, char *result, int maxlen)
+int parse_date(const char *date, char *result, int maxlen)
 {
 	struct tm tm;
-	int offset;
+	int offset, tm_gmt;
 	time_t then;
 
 	memset(&tm, 0, sizeof(tm));
@@ -259,6 +409,7 @@ void parse_date(char *date, char *result, int maxlen)
 	tm.tm_mday = -1;
 	tm.tm_isdst = -1;
 	offset = -1;
+	tm_gmt = 0;
 
 	for (;;) {
 		int match = 0;
@@ -271,7 +422,7 @@ void parse_date(char *date, char *result, int maxlen)
 		if (isalpha(c))
 			match = match_alpha(date, &tm, &offset);
 		else if (isdigit(c))
-			match = match_digit(date, &tm, &offset);
+			match = match_digit(date, &tm, &offset, &tm_gmt);
 		else if ((c == '-' || c == '+') && isdigit(date[1]))
 			match = match_tz(date, &offset);
 
@@ -289,11 +440,11 @@ void parse_date(char *date, char *result, int maxlen)
 		offset = (then - mktime(&tm)) / 60;
 
 	if (then == -1)
-		return;
-
-	then -= offset * 60;
+		return -1;
 
-	snprintf(result, maxlen, "%lu %+03d%02d", then, offset/60, offset % 60);
+	if (!tm_gmt)
+		then -= offset * 60;
+	return date_string(then, offset, result, maxlen);
 }
 
 void datestamp(char *buf, int bufsize)
@@ -306,5 +457,188 @@ void datestamp(char *buf, int bufsize)
 	offset = my_mktime(localtime(&now)) - now;
 	offset /= 60;
 
-	snprintf(buf, bufsize, "%lu %+05d", now, offset/60*100 + 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 const struct special {
+	const char *name;
+	void (*fn)(struct tm *, int *);
+} special[] = {
+	{ "yesterday", date_yesterday },
+	{ "noon", date_noon },
+	{ "midnight", date_midnight },
+	{ "tea", date_tea },
+	{ 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 n = 1, i;
+
+	while (isalpha(*++end))
+		n++;
+
+	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;
+}
+
+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)) {
+			char *end;
+			number = strtoul(date-1, &end, 10);
+			date = end;
+			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);
 }