slurpd and back-config

[Howard Chu <hyc@symas.com>]

It doesn't seem worthwhile to pull in all the changes needed to bring 
slurpd up to date here. I'm more inclined to implement slurpd-like 
functionality in slapd, and delete slurpd.

First we could move the existing replog functionality into an overlay, 
as I've suggested before. Next the overlay itself could submit update 
tasks (using the thread pool or the runqueue, as appropriate) to update 
remote servers. It could use libldap_r directly, or it could operate 
through back-ldap/back-meta. I'm somewhat favoring the 
back-ldap/back-meta approach, as it opens the possibility to use the 
rewrite overlay in the replication process.

The one thing we'd lack is a standalone/one-shot mode, but we could 
create a slaptool for that purpose. E.g., define a SLAP_BFLAG for 
"one-shot" mode; whenever the tool runs it will invoke all the 
backends/whatever that have this flag defined and skip anything that 
doesn't have it defined.

--
 -- Howard Chu
 Chief Architect, Symas Corp.       Director, Highland Sun
 http://www.symas.com               http://highlandsun.com/hyc
 Symas: Premier OpenSource Development and Support