slapd ABIs

["Kurt D. Zeilenga" <Kurt@OpenLDAP.org>]

It's been noted that slapd now two ABIs for plugins.

slapd module interface
	This interface is considered the "native" slapd
	ABI.  As a "native" slapd, it tuned to slapd
	internals (and slapd to it).  It requires no
	"compatibility layer".

NS-SLAPI
	The NS-SLAPI provides compatibility with
       plugins designed for use with the Sun, Netscape
	(and, formally, iPlanet) Directory server.
	It requires a "compatibility layer".  It's not
	especially tuned slapd (nor slapd to it).


>From a design perspective, I would prefer that
NS-SLAPI be implemented as a layer on top of the module
interface so that main line code need only to
make one callout.  However, in reality, this may not
always be possible.   However, it should always be
possible to compile slapd (with or without modules)
without NS-SLAPI.

We should avoid OpenLDAP-specific extensions to
NS-SLAPI and they are counter to the purpose of
this ABI.

Kurt