An indexer factory function should set values for the following in the parameter block before returning control to Directory Server:
SLAPI_PLUGIN_DESTROY_FN, a pointer to the destructor for the filter object
SLAPI_PLUGIN_MR_FILTER_INDEX_FN, a pointer to the filter index function
SLAPI_PLUGIN_MR_FILTER_MATCH_FN, a pointer to the filter match function
SLAPI_PLUGIN_MR_FILTER_RESET_FN, if required, a pointer to the filter reset function
SLAPI_PLUGIN_MR_FILTER_REUSABLE, if required to specify that the filter can be reused
SLAPI_PLUGIN_OBJECT, a pointer to the filter object
Refer to Chapter 18, Parameter Block Reference for details.