Re: [Patch] pg_rewind: options to use restore_command fromrecovery.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

Postgres Professional https://www.postgrespro.com
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