tdb_chainlock() in tdb1, tdb2 and tdb_compat ?

[Rusty Russell]

On Thu, 12 Apr 2012 13:55:59 -0700, Jeremy Allison <jra at samba.org> wrote:
> > So hypothetical callers checking
> > 
> > if (tdb_chainlock(...) == -1) {
> > 	/* error path */
> > }
> > 
> > silently would become wrong.
> 
> Ouch. This is a *BIG* API problem (IMHO). Any tdb_compat()
> layer has to provide *exact* tdb1 semantics or we're setting
> ourselves up for a world of pain with different semantics
> called from code that doesn't expect it.

Indeed, that's why I audited SAMBA for all such uses.  I have a patch
which does some very nasty things to check for such abuse.

The intent for tdb_compat was to be temporary, though it's lasted longer
than I'd hoped as we tried to make sure people could still select tdb1
if we broke things.

Cheers,
Rusty.