X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fstruct%2Flist.h;h=b970b7cf2d3355af09f9706815a854e029e1d4c1;hb=efaa76e41313ea66ca001bd09948d90c52e58c5c;hp=05223caa01f70705e23435ce795c968470e98c80;hpb=9002e60f9cc2f2112180d706abe7dfc4f14ebf0f;p=bertos.git

diff --git a/bertos/struct/list.h b/bertos/struct/list.h
index 05223caa..b970b7cf 100644
--- a/bertos/struct/list.h
+++ b/bertos/struct/list.h
@@ -32,7 +32,7 @@
  *
  * \brief General pourpose double-linked lists
  *
- * \version $Id: list.h 1594 2008-08-10 12:20:10Z bernie $
+ * \version $Id$
  * \author Bernie Innocenti <bernie@codewiz.org>
  */
 
@@ -216,6 +216,7 @@ typedef struct _PriNode
 	#define INVALIDATE_NODE(n) ((n)->succ = (n)->pred = NULL)
 #else
 	#define LIST_ASSERT_VALID(l) do {} while (0)
+	#define LIST_ASSERT_NOT_CONTAINS(list,node) do {} while (0)
 	#define INVALIDATE_NODE(n) do {} while (0)
 #endif
 
@@ -275,9 +276,24 @@ typedef struct _PriNode
 /**
  * Insert a priority node in a priority queue.
  *
- * The new node is inserted immediately before the
- * first node with lower priority or appended to
- * the tail if no such node exists.
+ * The new node is inserted immediately before the first node with the same
+ * priority or appended to the tail if no such node exists.
+ */
+#define LIST_ENQUEUE_HEAD(list, node) \
+	do { \
+		PriNode *ln; \
+		LIST_ASSERT_NOT_CONTAINS((list),(node)); \
+		FOREACH_NODE(ln, (list)) \
+			if (ln->pri <= (node)->pri) \
+				break; \
+		INSERT_BEFORE(&(node)->link, &ln->link); \
+	} while (0)
+
+/**
+ * Insert a priority node in a priority queue.
+ *
+ * The new node is inserted immediately before the first node with lower
+ * priority or appended to the tail if no such node exists.
  */
 #define LIST_ENQUEUE(list, node) \
 	do { \