Date: Thu, 21 Nov 2024 12:14:47 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Bruce Momjian <bruce@momjian.us>
Cc: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>,
	Tom Lane <tgl@sss.pgh.pa.us>, adam@labkey.com,
	pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18711: Attempting a connection with a database name longer
 than 63 characters now fails
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On Thu, Nov 21, 2024 at 01:05:38PM -0500, Bruce Momjian wrote:
> On Thu, Nov 21, 2024 at 11:09:14AM -0600, Nathan Bossart wrote:
>> Yes, we still need to do that if it's possible the truncation wiped out
>> part of a multi-byte character.  But it's not possible that we truncated
>> part of a multi-byte character if the NAMEDATALEN-1'th or NAMEDATALEN-2'th
>> byte is ASCII, in which case we can avoid doing extra lookups.
> 
> Why would you check for two characters at the end rather than just a
> normal check in the main loop?

It might be possible to integrate this check into the loop, which could
potentially be cleaner.  The reason I didn't at first is because it
requires checking a byte that we will have already truncated away.  We have
to look at the original, non-truncated string for that.  I'll give it a try
(unless Bertrand beats me to it).

>> What more do you think is required?
> 
> I think the IS_HIGHBIT_SET needs to be integrated into the 'for' loop
> more clearly;  the 'if' check plus the comment above it is just
> confusing.

Got it.  Thank you for reviewing.

-- 
nathan