Re: Fixing code that ignores failure of XLogRecGetBlockTag

On Tue, Apr 12, 2022 at 8:58 AM Robert Haas <robertmhaas@gmail.com> wrote:
> On Mon, Apr 11, 2022 at 2:20 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > Currently, XLogRecGetBlockTag has 41 callers, of which only four
> > bother to check the function's result.  The remainder take it on
> > faith that they got valid data back, and many of them will
> > misbehave in seriously nasty ways if they didn't.  (This point
> > was drawn to my attention by a Coverity complaint.)
> >
> > I think we should make this a little less fragile.  Since we
> > already have XLogRecGetBlockTagExtended, I propose that callers
> > that need to handle the case of no-such-block must use that,
> > while XLogRecGetBlockTag throws an error.  The attached patch
> > fixes that up, and also cleans up some random inconsistency
> > about use of XLogRecHasBlockRef().
>
> Looks reasonable.

+1