Re: [PATCH] Make pg_basebackup configure and start standby [Review]

2013-01-02 01:24 keltezéssel, Tom Lane írta:
> Boszormenyi Zoltan <zb@cybertec.at> writes:
>> 2013-01-01 17:18 keltezéssel, Magnus Hagander írta:
>>> That way we can get around the whole need for changing memory allocation across all the
>>> frontends, no? Like the attached.
>> Sure it's simpler but then the consistent look of the code is lost.
>> What about the other patch to unify pg_malloc and friends?
>> Basically all client code boils down to
>>       fprintf(stderr, ...)
>> in different disguise in their error reporting, so that patch can
>> also be simplified but it seems that the atexit() - either explicitly
>> or hidden behind InitPostgresFrontend() - cannot be avoided.
> Meh.  I find it seriously wrongheaded that something as minor as an
> escape_quotes() function should get to dictate both malloc wrappers
> and error recovery handling throughout every program that might use it.

Actually, the unification of pg_malloc and friends wasn't dictated
by this little code, it was just that pg_basebackup doesn't provide
a pg_malloc implementation (only pg_malloc0) that is used by
initdb's escape_quotes() function. Then I noticed how wide these
almost identical functions have spread into client apps already.

I would say this unification patch is completely orthogonal to
the patch in $SUBJECT. I will post it in a different thread if it's
wanted at all. The extra atexit() handler is not needed if a simple
fprintf(stderr, ...) error reporting is enough in all clients.
As far as I saw, all clients do exactly this but some of them hide
this behind #define's.

> I like Magnus' version a lot better than that idea.

OK, I will post the core patch building on his code.

> A bigger issue that I notice with this code is that it's only correct in
> backend-safe encodings, as the comment mentions.  If we're going to be
> putting it into frontend programs, how safe is that going to be?
>
>             regards, tom lane

The question in a different form is: does PostgreSQL support
non-ASCII-safe encodings at all (or on the client side)? Forgive
my ignorance and enlighten me: how many such encodings
exist besides EBCDIC? Is UTF-16 non-ASCII-safe?

Best regards,
Zoltán Böszörményi

--
----------------------------------
Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
Gröhrmühlgasse 26
A-2700 Wiener Neustadt, Austria
Web: http://www.postgresql-support.de     http://www.postgresql.at/