Re: Error-safe user functions

On Fri, Dec 23, 2022 at 9:20 AM Andrew Dunstan <andrew(at)dunslane(dot)net> wrote:

>
> On 2022-12-22 Th 11:44, Tom Lane wrote:
> > Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> >> Yeah, I started there, but it's substantially more complex - unlike cube
> >> the jsonpath scanner calls the error routines as well as the parser.
> >> Anyway, here's a patch.
> > I looked through this and it seems generally OK. A minor nitpick is
> > that we usually write "(Datum) 0" not "(Datum) NULL" for dont-care Datum
> > values.
>
>
> Fixed in the new version attached.
>
>
> > A slightly bigger issue is that makeItemLikeRegex still allows
> > an error to be thrown from RE_compile_and_cache if a bogus regex is
> > presented. But that could be dealt with later.
>
>
> I'd rather fix it now while we're paying attention.
>
>
> >
> > (I wonder why this is using RE_compile_and_cache at all, really,
> > rather than some other API. There doesn't seem to be value in
> > forcing the regex into the cache at this point.)
> >
> >
>
>
> I agree. The attached uses pg_regcomp instead. I had a lift a couple of
> lines from regexp.c, but not too many.
>
>
> cheers
>
>
> andrew
>
>
> --
> Andrew Dunstan
> EDB: https://www.enterprisedb.com

Hi,
In makeItemLikeRegex :

+ /* See regexp.c for explanation */
+ CHECK_FOR_INTERRUPTS();
+ pg_regerror(re_result, &re_tmp, errMsg,
sizeof(errMsg));
+ ereturn(escontext, false,

Since an error is returned, I wonder if the `CHECK_FOR_INTERRUPTS` call is
still necessary.

Cheers