Re: Better error reporting from extension scripts (Was: Extend ALTER OPERATOR)

Alexander Law <exclusion@gmail.com>

From: Alexander Lakhin <exclusion@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andrew Dunstan <andrew@dunslane.net>, buildfarm@sraoss.co.jp, Pavel Stehule <pavel.stehule@gmail.com>, Christoph Berg <myon@debian.org>, Michael Banck <mbanck@gmx.net>, Tommy Pavlicek <tommypav122@gmail.com>, Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>, pgsql-hackers@lists.postgresql.org, jian.universality@gmail.com
Date: 2024-10-28T19:00:00Z
Lists: pgsql-hackers
28.10.2024 19:06, Tom Lane wrote:
>> I've also dumped buf in read_whole_file() and found that in both
>> PG_BINARY_R and "r" modes the 0d 0a ending is preserved. But it changed
>> to 0a with the "rt" mode (see [1]), and it makes the test (and the whole
>> `meson test`) pass for me.
> Interesting.  I believe we decided years ago that we didn't need to
> use "rt" mode because that was the default on Windows, but was that
> a misreading of the documentation?  The link you provided doesn't
> give any hint that there are more than two behaviors.
>
> However ... the link you provided also mentions that text mode
> includes treating control-Z as EOF; which I'd forgotten, but it
> does make it less safe than I thought to use text mode for
> reading script files.

I think that this other behavior can be explained by pgwin32_fopen()/
pgwin32_open() coding (O_TEXT assumed implicitly only #ifdef FRONTEND).

Anyway, as you noticed, \x1A injected into test_ext....sql really leads to
the file contents truncation on read (with "rt"), so I agree that using the
text/translation mode here is not an improvement.

> What I'm now thinking is that we should revert 924e03917 after
> all (that is, go back to using PG_BINARY_R) and instead make
> read_whole_file manually squash \r\n to \n if we're on Windows.
> Ugly, but I have yet to find anything about that platform that
> isn't.

Yes, I think this should help.

Best regards,
Alexander



Commits

  1. Strip Windows newlines from extension script files manually.

  2. Read extension script files in text not binary mode.

  3. Improve reporting of errors in extension script files.

  4. Improve parser's reporting of statement start locations.

  5. Extend ALTER OPERATOR to allow setting more optimization attributes.

  6. Core support for "extensions", which are packages of SQL objects.