CIRCLEQs are a disgrace to everything Knuth taught us in Volume 1 Chapter 2.

Retire them before anybody starts to use them again.

Use TAILQ instead, it provides the same functionality.

1 files changed, 18 insertions, 124 deletions

diff --git a/sys/sys/queue.h b/sys/sys/queue.h
index ab232b8..a4f09b1 100644
--- a/sys/sys/queue.h
+++ b/sys/sys/queue.h
@@ -78,35 +78,27 @@
  * after an existing element, at the head of the list, or at the end of
  * the list. A tail queue may be traversed in either direction.
  *
- * A circle queue is headed by a pair of pointers, one to the head of the
- * list and the other to the tail of the list. The elements are doubly
- * linked so that an arbitrary element can be removed without a need to
- * traverse the list. New elements can be added to the list before or after
- * an existing element, at the head of the list, or at the end of the list.
- * A circle queue may be traversed in either direction, but has a more
- * complex end of list detection.
- *
  * For details on the use of these macros, see the queue(3) manual page.
  *
  *
- *			SLIST	LIST	STAILQ	TAILQ	CIRCLEQ
- * _HEAD		+	+	+	+	+
- * _HEAD_INITIALIZER	+	+	+	+	+
- * _ENTRY		+	+	+	+	+
- * _INIT		+	+	+	+	+
- * _EMPTY		+	+	+	+	+
- * _FIRST		+	+	+	+	+
- * _NEXT		+	+	+	+	+
- * _PREV		-	-	-	+	+
- * _LAST		-	-	+	+	+
- * _FOREACH		+	+	+	+	+
- * _FOREACH_REVERSE	-	-	-	+	+
- * _INSERT_HEAD		+	+	+	+	+
- * _INSERT_BEFORE	-	+	-	+	+
- * _INSERT_AFTER	+	+	+	+	+
- * _INSERT_TAIL		-	-	+	+	+
- * _REMOVE_HEAD		+	-	+	-	-
- * _REMOVE		+	+	+	+	+
+ *			SLIST	LIST	STAILQ	TAILQ
+ * _HEAD		+	+	+	+
+ * _HEAD_INITIALIZER	+	+	+	+
+ * _ENTRY		+	+	+	+
+ * _INIT		+	+	+	+
+ * _EMPTY		+	+	+	+
+ * _FIRST		+	+	+	+
+ * _NEXT		+	+	+	+
+ * _PREV		-	-	-	+
+ * _LAST		-	-	+	+
+ * _FOREACH		+	+	+	+
+ * _FOREACH_REVERSE	-	-	-	+
+ * _INSERT_HEAD		+	+	+	+
+ * _INSERT_BEFORE	-	+	-	+
+ * _INSERT_AFTER	+	+	+	+
+ * _INSERT_TAIL		-	-	+	+
+ * _REMOVE_HEAD		+	-	+	-
+ * _REMOVE		+	+	+	+
  *
  */
 
@@ -412,104 +404,6 @@ struct {								\
 	*(elm)->field.tqe_prev = TAILQ_NEXT((elm), field);		\
 } while (0)
 
-/*
- * Circular queue declarations.
- */
-#define	CIRCLEQ_HEAD(name, type)					\
-struct name {								\
-	struct type *cqh_first;		/* first element */		\
-	struct type *cqh_last;		/* last element */		\
-}
-
-#define	CIRCLEQ_HEAD_INITIALIZER(head)					\
-	{ (void *)&(head), (void *)&(head) }
-
-#define	CIRCLEQ_ENTRY(type)						\
-struct {								\
-	struct type *cqe_next;		/* next element */		\
-	struct type *cqe_prev;		/* previous element */		\
-}
-
-/*
- * Circular queue functions.
- */
-#define	CIRCLEQ_EMPTY(head)	((head)->cqh_first == (void *)(head))
-
-#define	CIRCLEQ_FIRST(head)	((head)->cqh_first)
-
-#define	CIRCLEQ_FOREACH(var, head, field)				\
-	for ((var) = CIRCLEQ_FIRST((head));				\
-	    (var) != (void *)(head);					\
-	    (var) = CIRCLEQ_NEXT((var), field))
-
-#define	CIRCLEQ_FOREACH_REVERSE(var, head, field)			\
-	for ((var) = CIRCLEQ_LAST((head));				\
-	    (var) != (void *)(head);					\
-	    (var) = CIRCLEQ_PREV((var), field))
-
-#define	CIRCLEQ_INIT(head) do {						\
-	CIRCLEQ_FIRST((head)) = (void *)(head);				\
-	CIRCLEQ_LAST((head)) = (void *)(head);				\
-} while (0)
-
-#define	CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do {		\
-	CIRCLEQ_NEXT((elm), field) = CIRCLEQ_NEXT((listelm), field);	\
-	CIRCLEQ_PREV((elm), field) = (listelm);				\
-	if (CIRCLEQ_NEXT((listelm), field) == (void *)(head))		\
-		CIRCLEQ_LAST((head)) = (elm);				\
-	else								\
-		CIRCLEQ_PREV(CIRCLEQ_NEXT((listelm), field), field) = (elm);\
-	CIRCLEQ_NEXT((listelm), field) = (elm);				\
-} while (0)
-
-#define	CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do {		\
-	CIRCLEQ_NEXT((elm), field) = (listelm);				\
-	CIRCLEQ_PREV((elm), field) = CIRCLEQ_PREV((listelm), field);	\
-	if (CIRCLEQ_PREV((listelm), field) == (void *)(head))		\
-		CIRCLEQ_FIRST((head)) = (elm);				\
-	else								\
-		CIRCLEQ_NEXT(CIRCLEQ_PREV((listelm), field), field) = (elm);\
-	CIRCLEQ_PREV((listelm), field) = (elm);				\
-} while (0)
-
-#define	CIRCLEQ_INSERT_HEAD(head, elm, field) do {			\
-	CIRCLEQ_NEXT((elm), field) = CIRCLEQ_FIRST((head));		\
-	CIRCLEQ_PREV((elm), field) = (void *)(head);			\
-	if (CIRCLEQ_LAST((head)) == (void *)(head))			\
-		CIRCLEQ_LAST((head)) = (elm);				\
-	else								\
-		CIRCLEQ_PREV(CIRCLEQ_FIRST((head)), field) = (elm);	\
-	CIRCLEQ_FIRST((head)) = (elm);					\
-} while (0)
-
-#define	CIRCLEQ_INSERT_TAIL(head, elm, field) do {			\
-	CIRCLEQ_NEXT((elm), field) = (void *)(head);			\
-	CIRCLEQ_PREV((elm), field) = CIRCLEQ_LAST((head));		\
-	if (CIRCLEQ_FIRST((head)) == (void *)(head))			\
-		CIRCLEQ_FIRST((head)) = (elm);				\
-	else								\
-		CIRCLEQ_NEXT(CIRCLEQ_LAST((head)), field) = (elm);	\
-	CIRCLEQ_LAST((head)) = (elm);					\
-} while (0)
-
-#define	CIRCLEQ_LAST(head)	((head)->cqh_last)
-
-#define	CIRCLEQ_NEXT(elm,field)	((elm)->field.cqe_next)
-
-#define	CIRCLEQ_PREV(elm,field)	((elm)->field.cqe_prev)
-
-#define	CIRCLEQ_REMOVE(head, elm, field) do {				\
-	if (CIRCLEQ_NEXT((elm), field) == (void *)(head))		\
-		CIRCLEQ_LAST((head)) = CIRCLEQ_PREV((elm), field);	\
-	else								\
-		CIRCLEQ_PREV(CIRCLEQ_NEXT((elm), field), field) =	\
-		    CIRCLEQ_PREV((elm), field);				\
-	if (CIRCLEQ_PREV((elm), field) == (void *)(head))		\
-		CIRCLEQ_FIRST((head)) = CIRCLEQ_NEXT((elm), field);	\
-	else								\
-		CIRCLEQ_NEXT(CIRCLEQ_PREV((elm), field), field) =	\
-		    CIRCLEQ_NEXT((elm), field);				\
-} while (0)
 
 #ifdef _KERNEL