From: Kiran Rangoon <kiranrangoon0@gmail.com>
To: util-linux@vger.kernel.org
Cc: thomas@t-8ch.de, Kiran Rangoon <kiranrangoon0@gmail.com>
Subject: [PATCH v4 1/4] libuuid: simplify gregorian-to-unix offset calculation
Date: Tue, 23 Dec 2025 13:03:24 -0500 [thread overview]
Message-ID: <20251223180324.2733-1-kiranrangoon0@gmail.com> (raw)
In-Reply-To: <20251223180055.2396-1-kiranrangoon0@gmail.com>
Replace complex bit-shift offset calculation with a simple constant
definition for better readability and maintainability.
Signed-off-by: Kiran Rangoon <kiranrangoon0@gmail.com>
---
libuuid/src/uuid_time.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/libuuid/src/uuid_time.c b/libuuid/src/uuid_time.c
index c7516152b..e2b991d74 100644
--- a/libuuid/src/uuid_time.c
+++ b/libuuid/src/uuid_time.c
@@ -62,7 +62,8 @@ time_t __uuid_time(const uuid_t uu, struct timeval *ret_tv);
static uint64_t gregorian_to_unix(uint64_t ts)
{
- return ts - ((((uint64_t) 0x01B21DD2) << 32) + 0x13814000);
+ const uint64_t offset = 0x01B21DD213814000ULL;
+ return ts - offset;
}
static void uuid_time_v1(const struct uuid *uuid, struct timeval *tv)
--
2.47.3
next prev parent reply other threads:[~2025-12-23 18:03 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-12-13 20:04 [PATCH] libuuid: Fix pre-1970 UUID v1 timestamp wraparound Kiran Rangoon
2025-12-13 23:36 ` Thomas Weißschuh
2025-12-14 1:01 ` [PATCH v2] " Kiran Rangoon
2025-12-16 13:08 ` Thomas Weißschuh
2025-12-16 20:40 ` Kiran
2025-12-16 23:21 ` Thomas Weißschuh
2025-12-17 20:42 ` [PATCH v3 1/2] libuuid: Refactor UUID time conversion for pre-epoch dates Kiran Rangoon
2025-12-17 20:59 ` Kiran Rangoon
2025-12-18 21:31 ` Kiran Rangoon
2025-12-19 11:40 ` Thomas Weißschuh
2025-12-23 18:00 ` [PATCH v4 0/4] libuuid: Fix pre-1970 UUID timestamp overflow Kiran Rangoon
2025-12-23 18:00 ` [PATCH v4 1/4] libuuid: simplify gregorian-to-unix offset calculation Kiran Rangoon
2025-12-23 18:00 ` [PATCH v4 2/4] libuuid: refactor gregorian_to_unix to populate timeval directly Kiran Rangoon
2025-12-23 18:03 ` Kiran Rangoon [this message]
2025-12-23 18:22 ` [PATCH v4 0/4] libuuid: Fix pre-1970 UUID timestamp overflow Thomas Weißschuh
2025-12-28 8:47 ` Thomas Weißschuh
2025-12-23 18:04 ` [PATCH v4 3/4] libuuid: fix timestamp overflow for pre-1970 dates Kiran Rangoon
2025-12-23 18:05 ` [PATCH v4 4/4] tests: correct UUID timestamp test expectations Kiran Rangoon
2025-12-17 11:01 ` [PATCH v2] libuuid: Fix pre-1970 UUID v1 timestamp wraparound Karel Zak
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20251223180324.2733-1-kiranrangoon0@gmail.com \
--to=kiranrangoon0@gmail.com \
--cc=thomas@t-8ch.de \
--cc=util-linux@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox