+ if ( !txn ) {
+ struct mdb_info *mdb = (struct mdb_info *) be->be_private;
+ rc = mdb_txn_begin( mdb->mi_dbenv, NULL,
+ (slapMode & SLAP_TOOL_READONLY) ? MDB_RDONLY : 0, &txn );
+ if ( rc )
+ return NULL;
+ }
+ if ( !cursor ) {
+ struct mdb_info *mdb = (struct mdb_info *) be->be_private;
+ rc = mdb_cursor_open( txn, mdb->mi_id2entry, &cursor );
+ if ( rc ) {
+ mdb_txn_abort( txn );
+ txn = NULL;
+ return NULL;
+ }
+ }