wfcqueue: document first/next return values

[urcu.git] / urcu / static / wfcqueue.h

diff --git a/urcu/static/wfcqueue.h b/urcu/static/wfcqueue.h
index 99643be98c393310bc36d591262fcddd5f0227af..4b3535aaa83207a4f4eb801dc63150bef8f28bbc 100644 (file)
--- a/urcu/static/wfcqueue.h
+++ b/urcu/static/wfcqueue.h
@@ -262,6 +262,8 @@ ___cds_wfcq_first(struct cds_wfcq_head *head,
  * Used by for-like iteration macros in urcu/wfqueue.h:
  * __cds_wfcq_for_each_blocking()
  * __cds_wfcq_for_each_blocking_safe()
+ *
+ * Returns NULL if queue is empty, first node otherwise.
  */
 static inline struct cds_wfcq_node *
 ___cds_wfcq_first_blocking(struct cds_wfcq_head *head,
@@ -321,6 +323,9 @@ ___cds_wfcq_next(struct cds_wfcq_head *head,
  * Used by for-like iteration macros in urcu/wfqueue.h:
  * __cds_wfcq_for_each_blocking()
  * __cds_wfcq_for_each_blocking_safe()
+ *
+ * Returns NULL if reached end of queue, non-NULL next queue node
+ * otherwise.
  */
 static inline struct cds_wfcq_node *
 ___cds_wfcq_next_blocking(struct cds_wfcq_head *head,