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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ryan Lambert <ryan@rustprooflabs.com>
cc: pgsql-hackers@postgresql.org
Subject: Re: Fix XML handling with DOCTYPE
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Comments: In-reply-to Ryan Lambert <ryan@rustprooflabs.com>
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Ryan Lambert <ryan@rustprooflabs.com> writes:
> I'm investigating the issue I reported here:
> https://www.postgresql.org/message-id/flat/153478795159.1302.96175864663=
68699403%40wrigleys.postgresql.org
> I'd like to work on a patch to address this issue and make it work as
> advertised.

Good idea, because it doesn't seem like anybody else cares ...

> I see xmlParseBalancedChunkMemoryRecover that might provide the
> functionality needed.

TBH, our experience with libxml has not been so positive that I'd think
adding dependencies on new parts of its API would be a good plan.

Experimenting with different inputs, it seems like removing the
"<!DOCTYPE ...>" tag is enough to make it work.  So what I'm wondering
about is writing something like parse_xml_decl() to skip over that.

Bear in mind though that I know next to zip about XML.  There may be
some good reason why we don't want to strip off the !DOCTYPE part
from what libxml sees.

			regards, tom lane