From: "Ævar Arnfjörð Bjarmason" <avarab@gmail.com>
To: Junio C Hamano <gitster@pobox.com>
Cc: Denton Liu <liu.denton@gmail.com>,
Git Mailing List <git@vger.kernel.org>,
Vincent Lefevre <vincent@vinc17.net>
Subject: Re: [PATCH] pager: exit without error on SIGPIPE
Date: Tue, 02 Feb 2021 03:05:36 +0100 [thread overview]
Message-ID: <87tuqvdy1b.fsf@evledraar.gmail.com> (raw)
In-Reply-To: <xmqq8s87ld8y.fsf@gitster.c.googlers.com>
On Mon, Feb 01 2021, Junio C Hamano wrote:
> Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:
>
>>> Would it be the matter of propagating the exit status of the pager
>>> noticed by wait_or_white() down thru finish_command_in_signal() and
>>> wait_for_pager(1) to here, so
>>>
>>> - If we know pager exited with non-zero status, we would report,
>>> perhaps with warning(_("..."));
>>>
>>> - If we notice we got a SIGPIPE, we ignore it---it is nothing of
>>> interest to the end-user;
>>>
>>> - Otherwise we do not do anything differently.
>>>
>>> would be sufficient? Implementors of "git -p" may know that "git"
>>> happens to implement its paging by piping its output to an external
>>> pager, but the end-users do not care. Implementors may say they are
>>> giving 'q' to their pager "less", but to the end-users, who report
>>> "I ran 'git log' and after reading a pageful, I told it to 'q'uit",
>>> the distinction does not have any importance.
>>>
>>> Or are there more to it, in that the exit status we get from the
>>> pager, combined with the kind of signal we are getting, is not
>>> sufficient for us to tell what is going on?
>>
>> It is, I just wonder if ignoring the exit code is a practical issue as
>> long as we're not clobbering SIGPIPE, particularly with my trace2
>> logging patch in this thread.
>>
>> But yeah, we could patch git to handle this in the general case....
>
> Sorry, but now you lost me.
>
> I was merely wondering if Denton's patch can become a small update
> on top of these, if we just made sure that the exit code of the
> pager noticed by wait_or_whine() is reported to the code where
> Denton makes the decision to say "let's not re-raise but simply exit
> with 0 return as what we got is SIGPIPE". I guess we could even
> make git exit with the pager's return code in that case, as the
> end-user observable result would be similar to "git log | less"
> where 'less' may be segfaulting or exiting cleanly.
>
> IOW, something like this on top of your three-patch series?
>
> pager.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git c/pager.c w/pager.c
> index 3d37dd7ada..73bc5fc0e4 100644
> --- c/pager.c
> +++ w/pager.c
> @@ -28,8 +28,14 @@ static void wait_for_pager_atexit(void)
>
> static void wait_for_pager_signal(int signo)
> {
> + int status;
> +
> close_pager_fds();
> - finish_command_in_signal(&pager_process);
> + status = finish_command_in_signal(&pager_process);
> +
> + if (signo == SIGPIPE)
> + exit(status);
> +
> sigchain_pop(signo);
> raise(signo);
> }
I sent a WIP start at something like this at the end of my v2, please
discard it when picking up the rest:
https://lore.kernel.org/git/20210202020001.31601-6-avarab@gmail.com/
As noted there it's going to be a lot more complex than this.
next prev parent reply other threads:[~2021-02-02 2:06 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-15 16:15 git fails with a broken pipe when one quits the pager Vincent Lefevre
2021-01-29 23:48 ` [PATCH] pager: exit without error on SIGPIPE Denton Liu
2021-01-30 8:29 ` Johannes Sixt
2021-01-30 12:52 ` Johannes Sixt
2021-02-01 15:03 ` Ævar Arnfjörð Bjarmason
2021-02-01 17:47 ` Junio C Hamano
2021-02-01 19:52 ` Ævar Arnfjörð Bjarmason
2021-02-01 20:55 ` Junio C Hamano
2021-02-02 2:05 ` Ævar Arnfjörð Bjarmason [this message]
2021-02-02 4:45 ` Junio C Hamano
2021-02-02 5:25 ` Junio C Hamano
2021-02-02 7:45 ` Johannes Sixt
2021-02-02 20:13 ` Junio C Hamano
2021-02-02 22:15 ` Johannes Sixt
2021-02-02 22:21 ` Junio C Hamano
2021-02-03 17:07 ` Johannes Sixt
2021-02-03 18:12 ` Junio C Hamano
2021-02-04 15:10 ` Vincent Lefevre
2021-02-03 2:45 ` Ævar Arnfjörð Bjarmason
2021-02-03 2:54 ` Junio C Hamano
2021-02-03 3:36 ` Ævar Arnfjörð Bjarmason
2021-02-03 17:19 ` Johannes Sixt
2021-01-31 1:47 ` git fails with a broken pipe when one quits the pager Ævar Arnfjörð Bjarmason
2021-01-31 3:36 ` Vincent Lefevre
2021-01-31 3:47 ` Vincent Lefevre
2021-01-31 20:49 ` Ævar Arnfjörð Bjarmason
2021-02-01 10:34 ` Vincent Lefevre
2021-02-01 11:33 ` Chris Torek
2021-02-01 12:36 ` Vincent Lefevre
2021-02-01 12:53 ` Chris Torek
2021-02-01 15:17 ` Vincent Lefevre
2021-02-01 15:00 ` Ævar Arnfjörð Bjarmason
2021-02-01 12:10 ` Ævar Arnfjörð Bjarmason
2021-02-01 14:48 ` Vincent Lefevre
2021-02-01 15:44 ` Ævar Arnfjörð Bjarmason
2021-02-01 22:16 ` Johannes Sixt
2021-02-03 2:48 ` Ævar Arnfjörð Bjarmason
2021-02-03 17:11 ` Johannes Sixt
2021-02-03 15:26 ` Vincent Lefevre
2021-02-04 0:14 ` Ævar Arnfjörð Bjarmason
2021-02-04 15:38 ` Vincent Lefevre
2021-02-01 14:49 ` [PATCH 0/3] pager: test for exit behavior & trace2 bug fix Ævar Arnfjörð Bjarmason
2021-02-02 1:59 ` [PATCH v2 0/5] " Ævar Arnfjörð Bjarmason
2021-02-02 1:59 ` [PATCH v2 1/5] pager: refactor wait_for_pager() function Ævar Arnfjörð Bjarmason
2021-02-02 1:59 ` [PATCH v2 2/5] pager: test for exit code with and without SIGPIPE Ævar Arnfjörð Bjarmason
2021-02-02 8:50 ` Denton Liu
2021-02-05 7:47 ` Johannes Sixt
2021-02-02 1:59 ` [PATCH v2 3/5] run-command: add braces for "if" block in wait_or_whine() Ævar Arnfjörð Bjarmason
2021-02-02 2:00 ` [PATCH v2 4/5] pager: properly log pager exit code when signalled Ævar Arnfjörð Bjarmason
2021-02-05 7:58 ` Johannes Sixt
2021-02-05 11:37 ` Junio C Hamano
2021-02-02 2:00 ` [WIP/PATCH v2 5/5] WIP pager: respect exit code of pager over SIGPIPE Ævar Arnfjörð Bjarmason
2021-02-01 14:49 ` [PATCH 1/3] pager: test for exit code Ævar Arnfjörð Bjarmason
2021-02-01 14:49 ` [PATCH 2/3] pager: refactor wait_for_pager() function Ævar Arnfjörð Bjarmason
2021-02-01 14:49 ` [PATCH 3/3] pager: properly log pager exit code when signalled Ævar Arnfjörð Bjarmason
2021-02-01 18:07 ` Junio C Hamano
2021-02-01 19:21 ` Ævar Arnfjörð Bjarmason
2021-02-01 18:15 ` Junio C Hamano
2021-02-01 19:23 ` Ævar Arnfjörð Bjarmason
2021-02-01 22:04 ` git fails with a broken pipe when one quits the pager Johannes Sixt
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=87tuqvdy1b.fsf@evledraar.gmail.com \
--to=avarab@gmail.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=liu.denton@gmail.com \
--cc=vincent@vinc17.net \
/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;
as well as URLs for NNTP newsgroup(s).