From c494cd1e7706d927ec0f586ffb2124e7e25cebb1 Mon Sep 17 00:00:00 2001
From: Bruce M Simpson <bms@FreeBSD.org>
Date: Wed, 24 Dec 2008 19:57:22 +0000
Subject: [PATCH] Add macro RB_FOREACH_SAFE(), which accepts an additional
 argument specifying a temporary tree node pointer. It may be used in a
 similar way to the *_SAFE() macros in <sys/queue.h>.

---
 sys/sys/tree.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sys/sys/tree.h b/sys/sys/tree.h
index 54ea6da5cc7..44c0c9950d1 100644
--- a/sys/sys/tree.h
+++ b/sys/sys/tree.h
@@ -737,6 +737,11 @@ name##_RB_MINMAX(struct name *head, int val)				\
 	     (x) != NULL;						\
 	     (x) = name##_RB_NEXT(x))
 
+#define RB_FOREACH_SAFE(x, name, head, y)				\
+	for ((x) = RB_MIN(name, head);					\
+	     (x) != NULL && ((y) = name##_RB_NEXT(x));			\
+	     (x) = (y))
+
 #define RB_FOREACH_REVERSE(x, name, head)				\
 	for ((x) = RB_MAX(name, head);					\
 	     (x) != NULL;						\