Re: lwlocknames.h beautification attempt

On 2025-Mar-17, Robert Haas wrote:

> On Mon, Mar 17, 2025 at 2:43 AM Álvaro Herrera <alvherre(at)alvh(dot)no-ip(dot)org> wrote:
> > Tom didn't say he didn't like this change. He said he didn't like a
> > different change, which is not the one I committed.
>
> Sorry, I should have read the emails more carefully. I missed the fact
> that there were two different proposals. It was the idea of
> right-aligning things that I was unhappy about.

Ah, okay.

> So, no objection to what you actually committed... except that I don't
> think that using % specifiers in SOME places in a format string is
> better than using them in ALL the places. It's not broken because
> $lockidx can't contain a % sign, but in general I think when we switch
> from print to printf it's better for us to have the format string be a
> constant so that it's clear that we can't accidentally get an extra %
> escape in there depending on the values of variables being
> interpolated.

I suppose this is a reasonable complaint; however, I don't see an actual
problem here. Even if I hack the regexp in generate-lwlocknames.pl to
accept a %-sign in the lock name (and introduce a matching % in
wait_event_names.txt), then that % is emitted verbatim rather than
attempted to further expand. Is this because this is Perl rather than
C? I'm not sure.

Note that a % in the lock number (which also needs a regexp hack) can't
cause a problem either, because of the check that the lock numbers are
an ordered sequence.

I think it's quite difficult to cause actual problems here.

--
Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/