Ideas on using locking.tdb from Netatalk to implement combined share mode database

[Volker Lendecke]

On Wed, Feb 23, 2011 at 04:06:00PM +0100, Frank Lahm wrote:
> I'm in the process of a decent rewrite of certain Netatalk (Opensource
> AFP filserver) subsystems. One of them is acess/deny mode subsytem
> which is the AFP pendant to share modes in CIFS. We're currently
> storing these as brls -- an ancient but working hack.
> 
> I'm now about to rewrite this stuff to use a tbd database. In order to
> have a fully spec conforming cross-platform server (Samba for Win
> clients, Netatlak for AFP clients) it would be necessary to integrate
> both sytems.
> 
> So I went ahead poking around in source3, hoping I could find a way where
> - Netatalk's afpd processes would be able to use Samba's locking.tdb
> (if configured to do so)
> 
> I've found "include/smb_share_modes.h" and libsmbsharemodes which look
> promising.
> 
> Semantic differences [1] let aside for now, could this approach work out!

That would definitely be the right place to put it. It would
be an interesting project for many different reasons. Be
aware though that at this moment locking.tdb is being seen
as pretty much a Samba-internal database that we are free to
change when it becomes necessary. We just recently had to
change the format because some problems with hard links were
reported. The main challenge would be to coordinate those
format changes and potentially provide backwards
compatibility layers and such things. In theory we could
provide a common API wrapping that, but this would need to
be pretty well designed, because it needs to be FAST. It
also needs to back onto ctdb for clustered Samba.

Interesting, but challenging idea.

Volker

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