Netscape NETSCAPE DIRECTORY SERVER 6.2 - GATEWAY CUSTOMIZATION, Manual

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Understanding Matching Rule Plug-Ins
128 Netscape Directory Server Plug-In Programmer’s Guide • December 2003
Finding a Plug-In for Searching
To determine which matching rule plug-in is responsible for handling an
extensible match filter for a given matching rule (based on its OID), the server does
the following for each plug-in:
1.
In a new
Slapi_PBlock
parameter block, the server sets the following
parameters:
❍
Sets the OID in the
SLAPI_PLUGIN_MR_OID
parameter.
❍
Sets the type (from the filter) in the
SLAPI_PLUGIN_MR_TYPE
parameter.
❍
Sets the value (from the filter) in the
SLAPI_PLUGIN_MR_VALUE
parameter.
2.
Next, the server calls the filter factory function (specified in the
SLAPI_PLUGIN_MR_FILTER_CREATE_FN
parameter) for the plug-in.
3.
The server checks the
SLAPI_PLUGIN_MR_FILTER_MATCH_FN
parameter.
❍
If the parameter is NULL, the plug-in does not handle the matching rule
specified by that OID.
❍
If the parameter returns a filter matching function, this plug-in handles the
matching rule specified by that OID.
4.
Finally, the server gets the following information from the plug-in for future
use:
❍
The filter index function specified in the
SLAPI_PLUGIN_MR_FILTER_INDEX_FN
parameter
❍
The value specified in the
SLAPI_PLUGIN_MR_FILTER_REUSABLE
parameter
❍
The filter reset function specified in the
SLAPI_PLUGIN_MR_FILTER_RESET_FN
parameter
❍
The filter object specified in the
SLAPI_PLUGIN_OBJECT
parameter
❍
The filter destructor function specified in the
SLAPI_PLUGIN_DESTROY_FN
parameter
Information specified in the filter object is used by both the filter index function
and the filter matching function.