Date: Wed, 4 Dec 2019 10:38:17 -0300
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Andres Freund <andres@anarazel.de>
Cc: Alexey Bashtanov <bashtanov@imap.cc>,
	Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
	PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: log bind parameter values on error
Message-ID: <20191204133817.GA27976@alvherre.pgsql>
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> (Maybe do strnlen(maxlen), then count strnlen(1) starting at that point
> -- so if that returns >=1, print the "..."?)

So I found that I can make the code more reasonable with this simple
coding,

	if (maxlen > 0)
	{
		s = pnstrdup(s, maxlen);
		ellipsis = strnlen(s, maxlen + 1) > maxlen;
		/* enlarge while we can do so cheaply */
		enlargeStringInfo(str, maxlen);
	}

... but the problem is that we now compile stringinfo.c for frontend
environments also, and there's no pnstrdup() in frontends.  And to
introduce it, we'd need a configure check (because GNU libc has it) and
a src/port naive implementation and a fe_memutils.c addition.

Sigh.

Still, it's not that much code, so I'll just go do that and open a
separate thread for it.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services