Filter Object Destructor Function

A filter object destructor function frees memory that was allocated for a filter object set up by the filter factory function. Directory Server calls the destructor after the operation completes, passing the parameter block indicating the filter object as the value of SLAPI_PLUGIN_OBJECT.

Directory Server never calls a destructor for the same object concurrently.

Example 11–6 Filter Object and Destructor (matchingrule.c)

This code shows an example object and destructor.

#include "slapi-plugin.h"

typedef struct plg_filter_t            /* For manipulating filter obj. */
{   char          *  f_type;           /* Attribute type to match      */
    int              f_op;             /* Type of comparison
                                        * (<, <=, ==, >=, >, substr)
                                        * for the filter.              */
    struct berval ** f_values;         /* Array of values to match     */
} plg_filter_t;


/* Free memory allocated for the filter object.                        */
static int
plg_filter_destroy(Slapi_PBlock * pb)
{
    void         * obj  = NULL;        /* Server lets the plug-in      */
    plg_filter_t * fobj = NULL;        /* handle the object type.      */

    if (!slapi_pblock_get(pb, SLAPI_PLUGIN_OBJECT, &obj))
    {
        fobj = (plg_filter_t *)obj;
        if (fobj){
            slapi_ch_free((void **)&fobj->f_type);
                if (fobj->f_values){
                    ber_bvecfree(fobj->f_values);
                }
            slapi_ch_free((void **)&fobj);
        }
    }
    return 0;
}