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

[Jeremy Allison]

On Wed, Feb 23, 2011 at 08:51:03PM +0100, Frank Lahm wrote:
> 2011/2/23 Jeremy Allison <jra at samba.org>:
> > On Wed, Feb 23, 2011 at 08:24:52PM +0100, Frank Lahm wrote:
> >> 2011/2/23 Jeremy Allison <jra at samba.org>:
> >> > On Wed, Feb 23, 2011 at 04:06:00PM +0100, Frank Lahm wrote:
> >> >> Dear hackers,
> >> >>
> >> >> 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!
> >> >
> >> > libsmbsharemodes was designed for exactly this purpose and used
> >> > by the NetWare file sharing daemon code on Linux.
> >>
> >> Great!
> >>
> >> >
> >> > Let me know if it will work for you - changes and updates
> >> > are welcome !
> >>
> >> How is cleanup in case of eg a crash supposed to happen? There's no
> >> way to go through the locks by pid, deleting any lock for which the
> >> process is gone, is there?
> >> Or is such cleanup builtin ?
> >
> > smbd has this cleanup builtin. It's not built into the libsmbsharemodes
> > api.
> 
> So this cleanup has to be build into afpd, but for that ideally there
> should be an API in "smb_share_modes.h". Until that happens, any
> pointer how I could manually do the cleanup in afpd ?

You'll have to look at the Samba code. Might be worth while
adding a "cleanup" call into the API I suppose. It was only
designed to cooperate with an existing smbd, not run without
it.

Jeremy.