[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains
From: |
Eli Zaretskii |
Subject: |
bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains |
Date: |
Wed, 07 Jul 2021 22:20:50 +0300 |
> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: michael.albinus@gmx.de, ncaprisunfan@gmail.com, 49261@debbugs.gnu.org
> Date: Wed, 07 Jul 2021 20:58:29 +0200
>
> Eli Zaretskii <eliz@gnu.org> writes:
>
> > Even if it currently works, it's unsafe, IMO, to not have any
> > protection there. No one will remember that we rely on this not being
> > called early enough.
>
> Right. My reasoning was that it seemed unlikely to be a problem here,
> since the same function also (possibly) calls the Lisp functions
> userlock--ask-user-about-supersession-threat and ask-user-about-lock.
> But those are only called in some cases, so we're calling out to Lisp
> more now than before, and that may indeed be a problem.
Right, the call to userlock--ask-user-about-supersession-threat is
under some conditions that are rarely satisfied.
> I can add a check to whether the Lisp function is defined before calling
> (and then not do locking if it isn't) to be more defensive here?
I guess so.
> > So I'm asking whether the simplicity justifies the costs, here and
> > elsewhere.
>
> I agree with you 100% that it's important to take this into
> consideration when moving things from C to Lisp. In this particular
> case, I think the cost is justified, because this isn't a function
> that's called in a loop, and the other things it does (calling
> Fverify_visited_file_modtime and Ffile_exists_p, and actually creating
> the lock file) totally swamps any extra string consing, I think. (That
> is, it won't take measurably longer.)
If it triggers GC, it _will_ take significantly longer. But I won't
argue more about this, it's a lost battle anyway with current Emacs
development trends.
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, (continued)
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Eli Zaretskii, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Lars Ingebrigtsen, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Lars Ingebrigtsen, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Eli Zaretskii, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Lars Ingebrigtsen, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Lars Ingebrigtsen, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains,
Eli Zaretskii <=
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Eli Zaretskii, 2021/07/07
- bug#49261: 28.0.50; File Locking Breaks Presumptuous Toolchains, Lars Ingebrigtsen, 2021/07/07