path: root/date.c
diff options
authorJeff King <>2010-07-04 11:00:17 (GMT)
committerJunio C Hamano <>2010-07-05 18:57:07 (GMT)
commit9ba0f0334dd505f78e0374bbe857c5e202f5a778 (patch)
tree3cc507dba882fd65ce121e7838b699441ecf9050 /date.c
parentad9d8e8f0f13e054ee30fcdcdb51973ddcfadb37 (diff)
parse_date: fix signedness in timezone calculation
When no timezone is specified, we deduce the offset by subtracting the result of mktime from our calculated timestamp. However, our timestamp is stored as an unsigned integer, meaning we perform the subtraction as unsigned. For a negative offset, this means we wrap to a very high number, and our numeric timezone is in the millions of hours. You can see this bug by doing: $ TZ=EST \ GIT_AUTHOR_DATE='2010-06-01 10:00' \ git commit -a -m foo $ git cat-file -p HEAD | grep author author Jeff King <> 1275404416 +119304128 Instead, we should perform this subtraction as a time_t, the same type that mktime returns. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'date.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/date.c b/date.c
index 68cdcaa..3c981f7 100644
--- a/date.c
+++ b/date.c
@@ -635,7 +635,7 @@ int parse_date_toffset(const char *date, unsigned long *timestamp, int *offset)
/* mktime uses local timezone */
*timestamp = tm_to_time_t(&tm);
if (*offset == -1)
- *offset = (*timestamp - mktime(&tm)) / 60;
+ *offset = ((time_t)*timestamp - mktime(&tm)) / 60;
if (*timestamp == -1)
return -1;