X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=urcu%2Fwfstack.h;h=03fee8fb63f74bb3ca8a110e0c8eb971e5ba6937;hb=af67624df8d06ebaa5d72dd863a73d334611e900;hp=20d1882c867b979910ad6000b8c3b64a8879a0c7;hpb=8af2956c86ba7556b0f7de3ad999a6b29ffbab9a;p=urcu.git

diff --git a/urcu/wfstack.h b/urcu/wfstack.h
index 20d1882..03fee8f 100644
--- a/urcu/wfstack.h
+++ b/urcu/wfstack.h
@@ -38,9 +38,10 @@ extern "C" {
  * Stack implementing push, pop, pop_all operations, as well as iterator
  * on the stack head returned by pop_all.
  *
- * Wait-free operations: cds_wfs_push, __cds_wfs_pop_all.
- * Blocking operations: cds_wfs_pop, cds_wfs_pop_all, iteration on stack
- *                      head returned by pop_all.
+ * Wait-free operations: cds_wfs_push, __cds_wfs_pop_all, cds_wfs_empty,
+ *                       cds_wfs_first.
+ * Blocking operations: cds_wfs_pop, cds_wfs_pop_all, cds_wfs_next,
+ *                      iteration on stack head returned by pop_all.
  *
  * Synchronization table:
  *
@@ -57,6 +58,8 @@ extern "C" {
  * synchronization.
  */
 
+#define CDS_WFS_WOULDBLOCK	((void *) -1UL)
+
 /*
  * struct cds_wfs_node is returned by __cds_wfs_pop, and also used as
  * iterator on stack. It is not safe to dereference the node next
@@ -98,7 +101,7 @@ struct cds_wfs_stack {
  * For iteration on cds_wfs_head returned by __cds_wfs_pop_all or
  * cds_wfs_pop_all_blocking.
  */
-#define cds_wfs_first_blocking		_cds_wfs_first_blocking
+#define cds_wfs_first			_cds_wfs_first
 #define cds_wfs_next_blocking		_cds_wfs_next_blocking
 
 /* Pop locking with internal mutex */
@@ -154,7 +157,7 @@ extern struct cds_wfs_node *cds_wfs_pop_blocking(struct cds_wfs_stack *s);
 extern struct cds_wfs_head *cds_wfs_pop_all_blocking(struct cds_wfs_stack *s);
 
 /*
- * cds_wfs_first_blocking: get first node of a popped stack.
+ * cds_wfs_first: get first node of a popped stack.
  *
  * Content written into the node before enqueue is guaranteed to be
  * consistent, but no other memory ordering is ensured.
@@ -165,7 +168,7 @@ extern struct cds_wfs_head *cds_wfs_pop_all_blocking(struct cds_wfs_stack *s);
  *
  * Returns NULL if popped stack is empty, top stack node otherwise.
  */
-extern struct cds_wfs_node *cds_wfs_first_blocking(struct cds_wfs_head *head);
+extern struct cds_wfs_node *cds_wfs_first(struct cds_wfs_head *head);
 
 /*
  * cds_wfs_next_blocking: get next node of a popped stack.
@@ -182,6 +185,14 @@ extern struct cds_wfs_node *cds_wfs_first_blocking(struct cds_wfs_head *head);
  */
 extern struct cds_wfs_node *cds_wfs_next_blocking(struct cds_wfs_node *node);
 
+/*
+ * cds_wfs_next_nonblocking: get next node of a popped stack.
+ *
+ * Same as cds_wfs_next_blocking, but returns CDS_WFS_WOULDBLOCK if it
+ * needs to block.
+ */
+extern struct cds_wfs_node *cds_wfs_next_nonblocking(struct cds_wfs_node *node);
+
 /*
  * cds_wfs_pop_lock: lock stack pop-protection mutex.
  */
@@ -210,6 +221,14 @@ extern void cds_wfs_pop_unlock(struct cds_wfs_stack *s);
  */
 extern struct cds_wfs_node *__cds_wfs_pop_blocking(struct cds_wfs_stack *s);
 
+/*
+ * __cds_wfs_pop_nonblocking: pop a node from the stack.
+ *
+ * Same as __cds_wfs_pop_blocking, but returns CDS_WFS_WOULDBLOCK if
+ * it needs to block.
+ */
+extern struct cds_wfs_node *__cds_wfs_pop_nonblocking(struct cds_wfs_stack *s);
+
 /*
  * __cds_wfs_pop_all: pop all nodes from a stack.
  *
@@ -245,7 +264,7 @@ extern struct cds_wfs_head *__cds_wfs_pop_all(struct cds_wfs_stack *s);
  * consistent, but no other memory ordering is ensured.
  */
 #define cds_wfs_for_each_blocking(head, node)			\
-	for (node = cds_wfs_first_blocking(head);		\
+	for (node = cds_wfs_first(head);			\
 		node != NULL;					\
 		node = cds_wfs_next_blocking(node))
 
@@ -261,7 +280,7 @@ extern struct cds_wfs_head *__cds_wfs_pop_all(struct cds_wfs_stack *s);
  * consistent, but no other memory ordering is ensured.
  */
 #define cds_wfs_for_each_blocking_safe(head, node, n)			   \
-	for (node = cds_wfs_first_blocking(head),			   \
+	for (node = cds_wfs_first(head),				   \
 			n = (node ? cds_wfs_next_blocking(node) : NULL);   \
 		node != NULL;						   \
 		node = n, n = (node ? cds_wfs_next_blocking(node) : NULL))