unknownin/out patch (was [HACKERS] PQescapeBytea is not multibyte aware)

Tom Lane wrote:
> Joe Conway <mail(at)joeconway(dot)com> writes:
>
>>I think you're correct that in a client/database encoding mismatch
>>scenario, there would be bigger problems. Thoughts on this?
>
>
> This scenario is probably why Tatsuo wants PQescapeBytea to octalize
> everything with the high bit set; I'm not sure there's any lesser way
> out. Nonetheless, if UNKNOWN conversion introduces additional failures
> then it makes sense to fix that.
>
> regards, tom lane
>

Here's a patch to add unknownin/unknownout support. I also poked around
looking for places that assume UNKNOWN == TEXT. One of those was the
"SET" type in pg_type.h, which was using textin/textout. This one I took
care of in this patch. The other suspicious place was in
string_to_dataum (which is defined in both selfuncs.c and indxpath.c). I
wasn't too sure about those, so I left them be.

Regression tests all pass with the exception of horology, which also
fails on CVS tip. It looks like that is a daylight savings time issue
though.

Also as a side note, I can't get make check to get past initdb if I
configure with --enable-multibyte on CVS tip. Is there a known problem
or am I just being clueless . . .wait, let's qualify that -- am I being
clueless on this one issue? ;-)

Joe