date.c: Support iso8601 timezone formats

Timezone designators in the following formats are all valid according to
ISO8601:2004, section 4.3.2:

    [+-]hh, [+-]hhmm, [+-]hh:mm

but we have ignored the ones with colon so far.

Signed-off-by: Haitao Li <lihaitao@gmail.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/date.c b/date.c
index 896fbb48060c673b8dc2f2aa6ea3de3c1042fbd2..353e0a5e53f13c36549e65452931f254de3423c4 100644 (file)
--- a/date.c
+++ b/date.c
@@ -552,23 +552,35 @@ static int match_digit(const char *date, struct tm *tm, int *offset, int *tm_gmt
 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;
+       int hour = strtoul(date + 1, &end, 10);
+       int n = end - (date + 1);
+       int min = 0;
 
-       min = offset % 100;
-       hour = offset / 100;
+       if (n == 4) {
+               /* hhmm */
+               min = hour % 100;
+               hour = hour / 100;
+       } else if (n != 2) {
+               min = 99; /* random crap */
+       } else if (*end == ':') {
+               /* hh:mm? */
+               min = strtoul(end + 1, &end, 10);
+               if (end - (date + 1) != 5)
+                       min = 99; /* random crap */
+       } /* otherwise we parsed "hh" */
 
        /*
-        * 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.
+        * Don't accept any random crap. Even though some places have
+        * offset larger than 12 hours (e.g. Pacific/Kiritimati is at
+        * UTC+14), there is something wrong if hour part is much
+        * larger than that. We might also want to check that the
+        * minutes are divisible by 15 or something too. (Offset of
+        * Kathmandu, Nepal is UTC+5:45)
         */
-       if (min < 60 && n > 2) {
-               offset = hour*60+min;
+       if (min < 60 && hour < 24) {
+               int offset = hour * 60 + min;
                if (*date == '-')
                        offset = -offset;
-
                *offp = offset;
        }
        return end - date;

diff --git a/t/t0006-date.sh b/t/t0006-date.sh
index f87abb5a0682d7a2fc7c3947789301c4157d331d..1d29810a7a94dad15645869c2f4f015a470fa622 100755 (executable)
--- a/t/t0006-date.sh
+++ b/t/t0006-date.sh
@@ -40,6 +40,12 @@ check_parse 2008-02 bad
 check_parse 2008-02-14 bad
 check_parse '2008-02-14 20:30:45' '2008-02-14 20:30:45 +0000'
 check_parse '2008-02-14 20:30:45 -0500' '2008-02-14 20:30:45 -0500'
+check_parse '2008-02-14 20:30:45 -0015' '2008-02-14 20:30:45 -0015'
+check_parse '2008-02-14 20:30:45 -5' '2008-02-14 20:30:45 +0000'
+check_parse '2008-02-14 20:30:45 -5:' '2008-02-14 20:30:45 +0000'
+check_parse '2008-02-14 20:30:45 -05' '2008-02-14 20:30:45 -0500'
+check_parse '2008-02-14 20:30:45 -:30' '2008-02-14 20:30:45 +0000'
+check_parse '2008-02-14 20:30:45 -05:00' '2008-02-14 20:30:45 -0500'
 check_parse '2008-02-14 20:30:45' '2008-02-14 20:30:45 -0500' EST5
 
 check_approxidate() {