Add FOREACH_SAFE() data structure companions.

Part written by me, part taken from FreeBSD.

Okay guenther@, oga@ and probably matthew@.

2 files changed, 52 insertions, 2 deletions

diff --git a/sys/sys/queue.h b/sys/sys/queue.h
index 7f961edaa28..7bb159a129e 100644
--- a/sys/sys/queue.h
+++ b/sys/sys/queue.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: queue.h,v 1.33 2011/07/03 16:08:40 matthew Exp $	*/
+/*	$OpenBSD: queue.h,v 1.34 2011/07/09 00:19:45 pirofti Exp $	*/
 /*	$NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $	*/
 
 /*
@@ -117,6 +117,11 @@ struct {								\
 	    (var) != SLIST_END(head);					\
 	    (var) = SLIST_NEXT(var, field))
 
+#define	SLIST_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = SLIST_FIRST(head);				\
+	    (var) && ((tvar) = SLIST_NEXT(var, field), 1);		\
+	    (var) = (tvar))
+
 #define	SLIST_FOREACH_PREVPTR(var, varp, head, field)			\
 	for ((varp) = &SLIST_FIRST((head));				\
 	    ((var) = *(varp)) != SLIST_END(head);			\
@@ -191,6 +196,11 @@ struct {								\
 	    (var)!= LIST_END(head);					\
 	    (var) = LIST_NEXT(var, field))
 
+#define	LIST_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = LIST_FIRST(head);				\
+	    (var) && ((tvar) = LIST_NEXT(var, field), 1);		\
+	    (var) = (tvar))
+
 /*
  * List functions.
  */
@@ -269,6 +279,11 @@ struct {								\
 	    (var) != SIMPLEQ_END(head);					\
 	    (var) = SIMPLEQ_NEXT(var, field))
 
+#define	SIMPLEQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = SIMPLEQ_FIRST(head);				\
+	    (var) && ((tvar) = SIMPLEQ_NEXT(var, field), 1);		\
+	    (var) = (tvar))
+
 /*
  * Simple queue functions.
  */
@@ -343,11 +358,24 @@ struct {								\
 	    (var) != TAILQ_END(head);					\
 	    (var) = TAILQ_NEXT(var, field))
 
+#define	TAILQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = TAILQ_FIRST(head);					\
+	    (var) != TAILQ_END(head) &&					\
+	    ((tvar) = TAILQ_NEXT(var, field), 1);			\
+	    (var) = (tvar))
+
+
 #define TAILQ_FOREACH_REVERSE(var, head, headname, field)		\
 	for((var) = TAILQ_LAST(head, headname);				\
 	    (var) != TAILQ_END(head);					\
 	    (var) = TAILQ_PREV(var, headname, field))
 
+#define	TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar)	\
+	for ((var) = TAILQ_LAST(head, headname);			\
+	    (var) != TAILQ_END(head) &&					\
+	    ((tvar) = TAILQ_PREV(var, headname, field), 1);		\
+	    (var) = (tvar))
+
 /*
  * Tail queue functions.
  */
@@ -447,11 +475,23 @@ struct {								\
 	    (var) != CIRCLEQ_END(head);					\
 	    (var) = CIRCLEQ_NEXT(var, field))
 
+#define	CIRCLEQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = CIRCLEQ_FIRST(head);				\
+	    (var) != CIRCLEQ_END(head) &&				\
+	    ((tvar) = CIRCLEQ_NEXT(var, field), 1);			\
+	    (var) = (tvar))
+
 #define CIRCLEQ_FOREACH_REVERSE(var, head, field)			\
 	for((var) = CIRCLEQ_LAST(head);					\
 	    (var) != CIRCLEQ_END(head);					\
 	    (var) = CIRCLEQ_PREV(var, field))
 
+#define	CIRCLEQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar)	\
+	for ((var) = CIRCLEQ_LAST(head, headname);			\
+	    (var) != CIRCLEQ_END(head) && 				\
+	    ((tvar) = CIRCLEQ_PREV(var, headname, field), 1);		\
+	    (var) = (tvar))
+
 /*
  * Circular queue functions.
  */
diff --git a/sys/sys/tree.h b/sys/sys/tree.h
index 30c62b6d26c..80d0f538134 100644
--- a/sys/sys/tree.h
+++ b/sys/sys/tree.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: tree.h,v 1.12 2009/03/02 09:42:55 mikeb Exp $	*/
+/*	$OpenBSD: tree.h,v 1.13 2011/07/09 00:19:45 pirofti Exp $	*/
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * All rights reserved.
@@ -730,9 +730,19 @@ 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), 1);		\
+	     (x) = (y))
+
 #define RB_FOREACH_REVERSE(x, name, head)				\
 	for ((x) = RB_MAX(name, head);					\
 	     (x) != NULL;						\
 	     (x) = name##_RB_PREV(x))
 
+#define RB_FOREACH_REVERSE_SAFE(x, name, head, y)			\
+	for ((x) = RB_MAX(name, head);					\
+	    ((x) != NULL) && ((y) = name##_RB_PREV(x), 1);		\
+	     (x) = (y))
+
 #endif	/* _SYS_TREE_H_ */