Hi Folks,

I'm currently making my first steps into overlay development using OpenLDAP 2.4.15. Digging into some already existing overlays was very helpful. Thanks to the nice work!

My sample overlay is just for personal testing to get some kind of feeling how to handle the slapd(-overlay) API. All I want to do with my testing-overlay is to get some kind of datastructure-list of the attribute names used in the current search-filter.

For example processing the following filter (&(objectClass=*)(ou=test)(hasSubordinates=TRUE)) my overlay's _search-callback() should print out "objectClass, ou, hasSubordinates".

Of course I could (regexp) string-compare the filterstr contained in struct Filter but I thought there has to be a more slapd-API'ic way available. After browsing through the mailinglist and various openldap-source files my perhabs silly question is:

Is there some kind of Attribute-list (Attribute *) datastructure available that can be traversed (in a more linear way) getting the attributes (and might be the corresponding search-patterns used in a search-filter statement? By linaer I mean some kind of (pseudo-code):

Attribute attr; for(attr=filter->attrs;attr;attr=attrs->next;) { attr->a_desc... ... }

All I've seen so far is struct Filter with it's "filterstr" (char *) and its various pointers to f_desc, f_av_desc, f_and, f_or, f_list and so on. I've also had a look into function "test_filter()" and into translucent-overlay search-callback, both use switch-case constructions to strip (complex) filter-strings (struct Filter) into atoms. I think that's nearly what I would need - again. ;-)

Because the filter atomization has already been done during filter-processing my actual intention is to avoid coding (90% copy&paste) the nearly same filter-processing mechanism into my own overlay's _search()-callback in favor to use a might be already existing datastructure.

In the moment I'm in doubt splitting the search filter twice could not be very elegant nor very efficient regarding the resulting performance... Probably I've not understood the overlay-processing and datastructures correct, thus I'm looking forward to your advice, hints and help.

Thanks a lot!

Cheers Daniel