Add --date={local,relative,default}
[git/git.git] / date.c
diff --git a/date.c b/date.c
index 0ceccbe..a9b59a2 100644 (file)
--- a/date.c
+++ b/date.c
@@ -55,6 +55,32 @@ static struct tm *time_to_tm(unsigned long time, int 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 = my_mktime(&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(unsigned long time, int tz, enum date_mode mode)
 {
        struct tm *tm;
@@ -102,6 +128,9 @@ const char *show_date(unsigned long time, int tz, enum date_mode mode)
                /* Else fall back on absolute format.. */
        }
 
+       if (mode == DATE_LOCAL)
+               tz = local_tzoffset(time);
+
        tm = time_to_tm(time, tz);
        if (!tm)
                return NULL;
@@ -109,12 +138,14 @@ const char *show_date(unsigned long time, int tz, enum date_mode mode)
                sprintf(timebuf, "%04d-%02d-%02d", tm->tm_year + 1900,
                                tm->tm_mon + 1, tm->tm_mday);
        else
-               sprintf(timebuf, "%.3s %.3s %d %02d:%02d:%02d %d %+05d",
+               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, tz);
+                               tm->tm_year + 1900,
+                               (mode == DATE_LOCAL) ? 0 : ' ',
+                               tz);
        return timebuf;
 }