Fix idl_cache teardown again - skip if cache is empty

servers/slapd/back-bdb/init.c

@@ -71,8 +71,7 @@ bdb_db_init( BackendDB *be )
 #ifdef BDB_HIER
 	ldap_pvt_thread_mutex_init( &bdb->bi_modrdns_mutex );
 #endif
-	ldap_pvt_thread_mutex_init( &bdb->bi_cache.lru_head_mutex );
-	ldap_pvt_thread_mutex_init( &bdb->bi_cache.lru_tail_mutex );
+	ldap_pvt_thread_mutex_init( &bdb->bi_cache.lru_mutex );
 	ldap_pvt_thread_mutex_init( &bdb->bi_cache.c_count_mutex );
 	ldap_pvt_thread_mutex_init( &bdb->bi_cache.c_eifree_mutex );
 	ldap_pvt_thread_mutex_init( &bdb->bi_cache.c_dntree.bei_kids_mutex );
@@ -476,16 +475,18 @@ bdb_db_close( BackendDB *be )
 	if ( bdb->bi_idl_cache_max_size ) {
 		avl_free( bdb->bi_idl_tree, NULL );
 		bdb->bi_idl_tree = NULL;
-		entry = bdb->bi_idl_lru_head;
-		do {
-			next_entry = entry->idl_lru_next;
-			if ( entry->idl )
-				free( entry->idl );
-			free( entry->kstr.bv_val );
-			free( entry );
-			entry = next_entry;
-		} while ( entry != bdb->bi_idl_lru_head );
-		bdb->bi_idl_lru_head = bdb->bi_idl_lru_tail = NULL;
+		if ( bdb->bi_idl_lru_head ) {
+			entry = bdb->bi_idl_lru_head;
+			do {
+				next_entry = entry->idl_lru_next;
+				if ( entry->idl )
+					free( entry->idl );
+				free( entry->kstr.bv_val );
+				free( entry );
+				entry = next_entry;
+			} while ( entry != bdb->bi_idl_lru_head );
+			bdb->bi_idl_lru_head = bdb->bi_idl_lru_tail = NULL;
+		}
 	}
 
 	/* close db environment */
@@ -542,8 +543,7 @@ bdb_db_destroy( BackendDB *be )
 	bdb_attr_index_destroy( bdb );
 
 	ldap_pvt_thread_rdwr_destroy ( &bdb->bi_cache.c_rwlock );
-	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.lru_head_mutex );
-	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.lru_tail_mutex );
+	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.lru_mutex );
 	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.c_count_mutex );
 	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.c_eifree_mutex );
 	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.c_dntree.bei_kids_mutex );