From: Junio C Hamano <gitster@pobox.com>
To: Michael J Gruber <git@grubix.eu>
Cc: git@vger.kernel.org
Subject: Re: [PATCH 1/2] dir.c: avoid gcc warning
Date: Fri, 06 May 2022 13:21:33 -0700 [thread overview]
Message-ID: <xmqqy1zejtte.fsf@gitster.g> (raw)
In-Reply-To: <cd50ec73ddafaaeba04298ae79cbf625cc0d7697.1651859773.git.git@grubix.eu> (Michael J. Gruber's message of "Fri, 6 May 2022 20:04:05 +0200")
Michael J Gruber <git@grubix.eu> writes:
> Related to -Wstringop-overread.
>
> In fact, this may be a false positive, but reading until the correct end
> is desirable here anyways.
But the correct end is start + (end - start), not start + (end -
start + 1), isn't it? We've stripped trailing junk like /.git and
end is point at one byte beyond the end of URL to the repository.
E.g. for "https://auth@host/", we have advanced start to point at
"h" at the beginning of "host", and we have moved end back from
pointing at the NUL at the end to point at "/" at the end of
"host/".
We are trying to make sure that the resulting "host" string between
start and end do not have a slash to apply this special case.
If the original URL were "https://auth@host:4321/", the end points
at "/" at the end of "host:4321/", making the string to be checked
to "host:4321" and we are trying to see it has no '/' in it (which
is the case). By extending the string by one, memchr() will see the
'/' at the end that is outside.
This seems to be a behaviour breaking change and I am not sure what
we are trying to achieve with it. Is this a suggestion made by a
broken compiler you have, or something?
Puzzled....
> Signed-off-by: Michael J Gruber <git@grubix.eu>
> ---
> dir.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/dir.c b/dir.c
> index 26c4d141ab..32fcaae4c0 100644
> --- a/dir.c
> +++ b/dir.c
> @@ -3145,7 +3145,7 @@ char *git_url_basename(const char *repo, int is_bundle, int is_bare)
> * result in a dir '2222' being guessed due to backwards
> * compatibility.
> */
> - if (memchr(start, '/', end - start) == NULL
> + if (memchr(start, '/', end - start + 1) == NULL
> && memchr(start, ':', end - start) != NULL) {
> ptr = end;
> while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
next prev parent reply other threads:[~2022-05-06 20:21 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-06 18:04 [PATCH 0/2] quell a few gcc warnings Michael J Gruber
2022-05-06 18:04 ` [PATCH 1/2] dir.c: avoid gcc warning Michael J Gruber
2022-05-06 20:21 ` Junio C Hamano [this message]
2022-05-09 15:58 ` Taylor Blau
2022-05-07 6:14 ` Carlo Marcelo Arenas Belón
2022-05-06 18:04 ` [PATCH 2/2] http.c: " Michael J Gruber
2022-05-06 20:22 ` Junio C Hamano
2022-05-06 21:17 ` [PATCH] http.c: clear the 'finished' member once we are done with it Junio C Hamano
2022-05-07 5:40 ` Carlo Marcelo Arenas Belón
2022-05-07 18:42 ` Junio C Hamano
2022-05-07 19:11 ` Carlo Arenas
2022-05-23 21:58 ` Johannes Schindelin
2022-05-23 22:58 ` Junio C Hamano
2022-05-23 23:36 ` Junio C Hamano
2022-05-23 23:41 ` Johannes Schindelin
2022-05-24 0:02 ` Junio C Hamano
2022-05-24 6:31 ` Daniel Stenberg
2022-05-24 10:57 ` Johannes Schindelin
2022-05-24 17:45 ` Junio C Hamano
2022-05-26 14:15 ` Daniel Stenberg
2022-05-24 11:03 ` Johannes Schindelin
2022-05-24 17:15 ` Junio C Hamano
2022-05-24 20:16 ` Carlo Marcelo Arenas Belón
2022-05-24 20:45 ` Ævar Arnfjörð Bjarmason
2022-05-24 22:34 ` Junio C Hamano
2022-05-25 9:08 ` Michael J Gruber
2022-05-25 13:27 ` Ævar Arnfjörð Bjarmason
2022-05-24 22:16 ` Junio C Hamano
2022-05-24 23:19 ` Junio C Hamano
2022-05-25 2:02 ` Carlo Arenas
2022-05-24 20:38 ` Ævar Arnfjörð Bjarmason
2022-05-24 22:28 ` Junio C Hamano
2022-05-25 10:07 ` Johannes Schindelin
2022-05-25 16:40 ` Junio C Hamano
2022-05-06 20:41 ` [PATCH 2/2] http.c: avoid gcc warning Carlo Marcelo Arenas Belón
2022-05-09 11:22 ` [PATCH] detect-compiler: make detection independent of locale Michael J Gruber
2022-05-09 15:52 ` Junio C Hamano
2022-05-09 15:59 ` rsbecker
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
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=xmqqy1zejtte.fsf@gitster.g \
--to=gitster@pobox.com \
--cc=git@grubix.eu \
--cc=git@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.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
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 read-only IMAP folder(s) and NNTP newsgroup(s).