format-patch: fix two-argument special case, and make it easier to pick single commits
[gitweb.git] / date.c
diff --git a/date.c b/date.c
index b46f2ce344d53585901820b39dffc8cb4c631364..3e11500eda5e75a7ec354441fe4a24fd5ebf8bbc 100644 (file)
--- a/date.c
+++ b/date.c
@@ -4,8 +4,8 @@
  * Copyright (C) Linus Torvalds, 2005
  */
 
-#include <ctype.h>
 #include <time.h>
+#include <sys/time.h>
 
 #include "cache.h"
 
@@ -34,7 +34,7 @@ static const char *month_names[] = {
 };
 
 static const char *weekday_names[] = {
-       "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"
+       "Sundays", "Mondays", "Tuesdays", "Wednesdays", "Thursdays", "Fridays", "Saturdays"
 };
 
 /*
@@ -386,12 +386,23 @@ static int match_tz(const char *date, int *offp)
        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(const char *date, char *result, int maxlen)
+int parse_date(const char *date, char *result, int maxlen)
 {
        struct tm tm;
-       int offset, sign, tm_gmt;
+       int offset, tm_gmt;
        time_t then;
 
        memset(&tm, 0, sizeof(tm));
@@ -431,18 +442,11 @@ void parse_date(const char *date, char *result, int maxlen)
                offset = (then - mktime(&tm)) / 60;
 
        if (then == -1)
-               return;
+               return -1;
 
        if (!tm_gmt)
                then -= offset * 60;
-
-       sign = '+';
-       if (offset < 0) {
-               offset = -offset;
-               sign = '-';
-       }
-
-       snprintf(result, maxlen, "%lu %c%02d%02d", then, sign, offset/60, offset % 60);
+       return date_string(then, offset, result, maxlen);
 }
 
 void datestamp(char *buf, int bufsize)
@@ -455,5 +459,188 @@ 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--;
+       return mktime(&tm);
 }