timestamp_t: a new data type for timestamps

Git's source code assumes that unsigned long is at least as precise as
time_t. Which is incorrect, and causes a lot of problems, in particular
where unsigned long is only 32-bit (notably on Windows, even in 64-bit
versions).

So let's just use a more appropriate data type instead. In preparation
for this, we introduce the new `timestamp_t` data type.

By necessity, this is a very, very large patch, as it has to replace all
timestamps' data type in one go.

As we will use a data type that is not necessarily identical to `time_t`,
we need to be very careful to use `time_t` whenever we interact with the
system functions, and `timestamp_t` everywhere else.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/archive-zip.c b/archive-zip.c
index b429a8d..68df3d6 100644
--- a/archive-zip.c
+++ b/archive-zip.c
@@ -545,9 +545,17 @@ static void write_zip_trailer(const unsigned char *sha1)
 		write_or_die(1, sha1_to_hex(sha1), GIT_SHA1_HEXSZ);
 }
 
-static void dos_time(time_t *time, int *dos_date, int *dos_time)
+static void dos_time(timestamp_t *timestamp, int *dos_date, int *dos_time)
 {
-	struct tm *t = localtime(time);
+	time_t time;
+	struct tm *t;
+
+	if (date_overflows(*timestamp))
+		die("timestamp too large for this system: %"PRItime,
+		    *timestamp);
+	time = (time_t)*timestamp;
+	t = localtime(&time);
+	*timestamp = time;
 
 	*dos_date = t->tm_mday + (t->tm_mon + 1) * 32 +
 	            (t->tm_year + 1900 - 1980) * 512;