new ldb schema module

[Andrew Tridgell]

Simo,

 > Add a first very basic schema module
 > To use it you should provide a schema.ldb file where the schema is stored
 > and load the module in the ldb you want to have schema check activated

Can you explain why you decided to put the schema in a separate ldb,
rather than building it into a subtree of the existing ldb? For
example, using a basedn of "dn=schema" might make sense.

The reason for putting it in the one ldb is that it allows the
administrator to backup/restore and generally manipulate a database as
one file. I think one of the curses of OpenLDAP is that the schema
isn't integrated in the database itself.

The obvious format for the schema records is the one exported by LDAP
databases in the
   CN=$OBJECTCLASS,CN=Schema,CN=Configuration,... 
subtree. Is that what you've used?

I also think you really need to create some simple utility functions
to make the schema.c code more readable. Some of the lines of code are
over 190 chars wide, and nested 12 levels deep! A few well chosen
utility functions would help a lot.

Cheers, Tridge