Re: [Patch] pg_rewind: options to use restore_command from recovery.conf or command line

On 2020-03-26 10:34, Michael Paquier wrote:
> On Tue, Mar 24, 2020 at 12:22:16PM +0900, Michael Paquier wrote:
>> Thanks Alvaro and Alexander. 0001 has been applied as of e09ad07.
>> Now for 0002, let's see about it later. Attached is a rebased
>> version, with no actual changes.
>
> I was looking at this patch again today and I am rather fine with the
> existing semantics. Still I don't like much to name the frontend-side
> routine FrontendRestoreArchivedFile() and use a different name than
> the backend counterpart because we have to include xlog_internal.h in
> fe_archive.c to be able to grab XLOGDIR.
>
> So here is an idea: let's move the declaration of the routines part of
> xlogarchive.c to a new header, called xlogarchive.h, and then let's
> use the same routine name for the frontend and the backend in this
> second patch. We include xlog_internal.h already in many frontend
> tools, so that would clean up things a bit. Two extra things are the
> routines for the checkpointer as well as the variables like
> ArchiveRecoveryRequested. It may be nice to move those while on it,
> but I am not sure where and that's not actually required for this
> patch set so that could be addressed later if need be.
>
> Any thoughts?
>

The block of function declarations for xlogarchive.c inside
xlog_internal.h looks a bit dangling already, since all other functions
and variables defined/initialized in xlog.c. That way, it looks good to
me to move it outside.

The only one concern about using the same name I have is that later
someone may introduce a new variable or typedef inside xlogarchive.h. So
someone else would be required to include both fe_archive.h and
xlogarchive.h at once. But probably there should be a warning in the
header comment section against doing so.

Anyway, I have tried to do what you proposed and attached is a small
patch, that introduces xlogarchive.h.

Regards
--
Alexey Kondratov

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