From: Petr Pisar <petr.pisar@atlas.cz>
To: musl@lists.openwall.com
Subject: Re: [musl] strptime(s, "%Y-%j", &tm) does not update month and day
Date: Sun, 12 May 2024 09:54:13 +0200 [thread overview]
Message-ID: <ZkB1pX8wTRe-4lhV@album.bayer.uni.cx> (raw)
In-Reply-To: <20240511212853.GS10433@brightrain.aerifal.cx>
[-- Attachment #1: Type: text/plain, Size: 1351 bytes --]
V Sat, May 11, 2024 at 05:28:54PM -0400, Rich Felker napsal(a):
> On Sat, May 11, 2024 at 05:24:59PM +0200, Petr Pisar wrote:
> > Hello,
> >
> > When debugging a libisds test failure with musl-1.2.5
> > <https://bugs.gentoo.org/show_bug.cgi?id=928107>, I found that musl's
> > strptime() does not handle "%Y-%j" properly. It accepts the format, it parses
> > the input string, it returns a correct pointer past the input string, but it
> > does not update tm.tm_mon and tm.tm_mday fileds of the third argument.
>
> This is behaving as specified. Previously, the behavior was
> unspecified. POSIX has amended it for future issues as the resolution
> of https://austingroupbugs.net/view.php?id=1727 to read:
>
> The tm_yday member of the tm structure pointed to by tm shall be
> set to this number minus 1.
>
> strptime generally does not behave like mktime, doing
> normalizations/conversions.
>
I see. I thought that strptime() does the normalization. Reading
mktime() specification reveals it has a side effect of normalizing tm_yday
from tm_year, tm_mon, and tm_mday.
However, I need the oposite and I cannot find any standard library function
for that. I will probaly resort to my own implementation with the drawback
of assumption that rules for leap years in Gregorian calendar won't change.
-- Petr
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next prev parent reply other threads:[~2024-05-12 7:54 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-11 15:24 Petr Pisar
2024-05-11 21:28 ` Rich Felker
2024-05-12 7:54 ` Petr Pisar [this message]
2024-05-13 12:18 ` Rich Felker
2024-05-13 21:18 ` Thorsten Glaser
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=ZkB1pX8wTRe-4lhV@album.bayer.uni.cx \
--to=petr.pisar@atlas.cz \
--cc=musl@lists.openwall.com \
/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.
Code repositories for project(s) associated with this public inbox
https://git.vuxu.org/mirror/musl/
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).