wfstack: document first/next return values

[userspace-rcu.git] / urcu / static / wfstack.h

diff --git a/urcu/static/wfstack.h b/urcu/static/wfstack.h
index cd00de64e2880887ac27cef99b23ea0db1996584..1a0e4d7475bab6beca8ecf3dba2b242b88ae6634 100644 (file)
--- a/urcu/static/wfstack.h
+++ b/urcu/static/wfstack.h
@@ -9,7 +9,7 @@
  * TO BE INCLUDED ONLY IN LGPL-COMPATIBLE CODE. See urcu/wfstack.h for
  * linking dynamically with the userspace rcu library.
  *
- * Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * Copyright 2010-2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -291,6 +291,8 @@ _cds_wfs_pop_all_blocking(struct cds_wfs_stack *s)
  * Used by for-like iteration macros in urcu/wfstack.h:
  * cds_wfs_for_each_blocking()
  * cds_wfs_for_each_blocking_safe()
+ *
+ * Returns NULL if popped stack is empty, top stack node otherwise.
  */
 static inline struct cds_wfs_node *
 _cds_wfs_first_blocking(struct cds_wfs_head *head)
@@ -309,6 +311,9 @@ _cds_wfs_first_blocking(struct cds_wfs_head *head)
  * Used by for-like iteration macros in urcu/wfstack.h:
  * cds_wfs_for_each_blocking()
  * cds_wfs_for_each_blocking_safe()
+ *
+ * Returns NULL if reached end of popped stack, non-NULL next stack
+ * node otherwise.
  */
 static inline struct cds_wfs_node *
 _cds_wfs_next_blocking(struct cds_wfs_node *node)