Re: Shuffling xlog header files

Heikki Linnakangas wrote:
> Andres Freund's xlogreader patch contains a change to move the
> declarations of SQL-callable functions in xlogfuncs.c to a new
> header file, xlog_fn.h. The purpose is to allow xlog_internal.h to
> be included in a frontend program, as the PG_FUNCTION_ARGS and Datum
> used in the prototypes require fmgr.h, which is backend-only. I
> think his patch missed a trick: pg_basebackup, pg_controlinfo and
> pg_resetxlog currently use this for the same purpose:

Yeah, I noticed that after I proposed that.  I furthermore realized that
the whole xlog.h / xlog_internal.h split wasn't thorough enough; I think
there's some more useful reshuffling to be done in the xlog headers; in
particular I considered the idea that backend .c files that only need to
build and insert xlog records could use a very lean header that defined
only enough to get that task done, while others such as checkpointer,
walreceiver and sender (probably others) would require the more
extensive header.

I was a bit pressed for time so didn't get around to actually trying it
out.

So I don't object to your patch, but I do think that maybe we can go
even a bit further than this.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
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