X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/378393581903b274cb7a4d18e0d978071a6b592d..7ee9d059c4eecf68ae4f8b0fb99ae2471eda79af:/bsd/sys/queue.h?ds=sidebyside

diff --git a/bsd/sys/queue.h b/bsd/sys/queue.h
index feb16f76e..9ccb63e74 100644
--- a/bsd/sys/queue.h
+++ b/bsd/sys/queue.h
@@ -1,25 +1,31 @@
 /*
  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
  * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
  * 
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
-/*
+/*-
  * Copyright (c) 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -31,10 +37,6 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
@@ -59,7 +61,7 @@
 
 /*
  * This file defines five types of data structures: singly-linked lists,
- * slingly-linked tail queues, lists, tail queues, and circular queues.
+ * singly-linked tail queues, lists, tail queues, and circular queues.
  *
  * A singly-linked list is headed by a single forward pointer. The elements
  * are singly linked for minimum space and pointer manipulation overhead at
@@ -94,7 +96,7 @@
  * 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 tail queue may only be traversed in the forward direction.
+ * 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
@@ -103,42 +105,90 @@
  * 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.
+ * Note that circle queues are deprecated, because, as the removal log
+ * in FreeBSD states, "CIRCLEQs are a disgrace to everything Knuth taught
+ * us in Volume 1 Chapter 2. [...] Use TAILQ instead, it provides the same
+ * functionality." Code using them will continue to compile, but they
+ * are no longer documented on the man page.
  *
  * For details on the use of these macros, see the queue(3) manual page.
  *
  *
- *			SLIST	LIST	STAILQ	TAILQ	CIRCLEQ
- * _HEAD		+	+	+	+	+
- * _ENTRY		+	+	+	+	+
- * _INIT		+	+	+	+	+
- * _EMPTY		+	+	+	+	+
- * _FIRST		+	+	+	+	+
- * _NEXT		+	+	+	+	+
- * _PREV		-	-	-	+	+
- * _LAST		-	-	+	+	+
- * _FOREACH		+	+	-	+	+
- * _INSERT_HEAD		+	+	+	+	+
- * _INSERT_BEFORE	-	+	-	+	+
- * _INSERT_AFTER	+	+	+	+	+
- * _INSERT_TAIL		-	-	+	+	+
- * _REMOVE_HEAD		+	-	+	-	-
- * _REMOVE		+	+	+	+	+
+ *				SLIST	LIST	STAILQ	TAILQ	CIRCLEQ
+ * _HEAD			+	+	+	+	+
+ * _HEAD_INITIALIZER		+	+	+	+	-
+ * _ENTRY			+	+	+	+	+
+ * _INIT			+	+	+	+	+
+ * _EMPTY			+	+	+	+	+
+ * _FIRST			+	+	+	+	+
+ * _NEXT			+	+	+	+	+
+ * _PREV			-	-	-	+	+
+ * _LAST			-	-	+	+	+
+ * _FOREACH			+	+	+	+	+
+ * _FOREACH_SAFE		+	+	+	+	-
+ * _FOREACH_REVERSE		-	-	-	+	-
+ * _FOREACH_REVERSE_SAFE	-	-	-	+	-
+ * _INSERT_HEAD			+	+	+	+	+
+ * _INSERT_BEFORE		-	+	-	+	+
+ * _INSERT_AFTER		+	+	+	+	+
+ * _INSERT_TAIL			-	-	+	+	+
+ * _CONCAT			-	-	+	+	-
+ * _REMOVE_AFTER		+	-	+	-	-
+ * _REMOVE_HEAD			+	-	+	-	-
+ * _REMOVE_HEAD_UNTIL		-	-	+	-	-
+ * _REMOVE			+	+	+	+	+
+ * _SWAP			-	+	+	+	-
  *
  */
+#ifdef QUEUE_MACRO_DEBUG
+/* Store the last 2 places the queue element or head was altered */
+struct qm_trace {
+	char * lastfile;
+	int lastline;
+	char * prevfile;
+	int prevline;
+};
+
+#define	TRACEBUF	struct qm_trace trace;
+#define	TRASHIT(x)	do {(x) = (void *)-1;} while (0)
+
+#define	QMD_TRACE_HEAD(head) do {					\
+	(head)->trace.prevline = (head)->trace.lastline;		\
+	(head)->trace.prevfile = (head)->trace.lastfile;		\
+	(head)->trace.lastline = __LINE__;				\
+	(head)->trace.lastfile = __FILE__;				\
+} while (0)
+
+#define	QMD_TRACE_ELEM(elem) do {					\
+	(elem)->trace.prevline = (elem)->trace.lastline;		\
+	(elem)->trace.prevfile = (elem)->trace.lastfile;		\
+	(elem)->trace.lastline = __LINE__;				\
+	(elem)->trace.lastfile = __FILE__;				\
+} while (0)
+
+#else
+#define	QMD_TRACE_ELEM(elem)
+#define	QMD_TRACE_HEAD(head)
+#define	TRACEBUF
+#define	TRASHIT(x)
+#endif	/* QUEUE_MACRO_DEBUG */
 
 /*
- * Singly-linked List definitions.
+ * Singly-linked List declarations.
  */
-#define SLIST_HEAD(name, type)						\
+#define	SLIST_HEAD(name, type)						\
 struct name {								\
 	struct type *slh_first;	/* first element */			\
 }
- 
-#define SLIST_ENTRY(type)						\
+
+#define	SLIST_HEAD_INITIALIZER(head)					\
+	{ NULL }
+
+#define	SLIST_ENTRY(type)						\
 struct {								\
 	struct type *sle_next;	/* next element */			\
 }
- 
+
 /*
  * Singly-linked List functions.
  */
@@ -146,55 +196,72 @@ struct {								\
 
 #define	SLIST_FIRST(head)	((head)->slh_first)
 
-#define SLIST_FOREACH(var, head, field)					\
-	for((var) = (head)->slh_first; (var); (var) = (var)->field.sle_next)
+#define	SLIST_FOREACH(var, head, field)					\
+	for ((var) = SLIST_FIRST((head));				\
+	    (var);							\
+	    (var) = SLIST_NEXT((var), field))
 
-#define SLIST_INIT(head) {						\
-	(head)->slh_first = NULL;					\
-}
+#define	SLIST_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = SLIST_FIRST((head));				\
+	    (var) && ((tvar) = SLIST_NEXT((var), field), 1);		\
+	    (var) = (tvar))
 
-#define SLIST_INSERT_AFTER(slistelm, elm, field) do {			\
-	(elm)->field.sle_next = (slistelm)->field.sle_next;		\
-	(slistelm)->field.sle_next = (elm);				\
-} while (0)
+#define	SLIST_FOREACH_PREVPTR(var, varp, head, field)			\
+	for ((varp) = &SLIST_FIRST((head));				\
+	    ((var) = *(varp)) != NULL;					\
+	    (varp) = &SLIST_NEXT((var), field))
 
-#define SLIST_INSERT_HEAD(head, elm, field) do {			\
-	(elm)->field.sle_next = (head)->slh_first;			\
-	(head)->slh_first = (elm);					\
+#define	SLIST_INIT(head) do {						\
+	SLIST_FIRST((head)) = NULL;					\
 } while (0)
 
-#define SLIST_NEXT(elm, field)	((elm)->field.sle_next)
+#define	SLIST_INSERT_AFTER(slistelm, elm, field) do {			\
+	SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field);	\
+	SLIST_NEXT((slistelm), field) = (elm);				\
+} while (0)
 
-#define SLIST_REMOVE_HEAD(head, field) do {				\
-	(head)->slh_first = (head)->slh_first->field.sle_next;		\
+#define	SLIST_INSERT_HEAD(head, elm, field) do {			\
+	SLIST_NEXT((elm), field) = SLIST_FIRST((head));			\
+	SLIST_FIRST((head)) = (elm);					\
 } while (0)
 
-#define SLIST_REMOVE(head, elm, type, field) do {			\
-	if ((head)->slh_first == (elm)) {				\
+#define	SLIST_NEXT(elm, field)	((elm)->field.sle_next)
+
+#define	SLIST_REMOVE(head, elm, type, field) do {			\
+	if (SLIST_FIRST((head)) == (elm)) {				\
 		SLIST_REMOVE_HEAD((head), field);			\
 	}								\
 	else {								\
-		struct type *curelm = (head)->slh_first;		\
-		while( curelm->field.sle_next != (elm) )		\
-			curelm = curelm->field.sle_next;		\
-		curelm->field.sle_next =				\
-		    curelm->field.sle_next->field.sle_next;		\
+		struct type *curelm = SLIST_FIRST((head));		\
+		while (SLIST_NEXT(curelm, field) != (elm))		\
+			curelm = SLIST_NEXT(curelm, field);		\
+		SLIST_REMOVE_AFTER(curelm, field);			\
 	}								\
+	TRASHIT((elm)->field.sle_next);					\
+} while (0)
+
+#define SLIST_REMOVE_AFTER(elm, field) do {				\
+	SLIST_NEXT(elm, field) =					\
+	    SLIST_NEXT(SLIST_NEXT(elm, field), field);			\
+} while (0)
+
+#define	SLIST_REMOVE_HEAD(head, field) do {				\
+	SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field);	\
 } while (0)
 
 /*
- * Singly-linked Tail queue definitions.
+ * Singly-linked Tail queue declarations.
  */
-#define STAILQ_HEAD(name, type)						\
+#define	STAILQ_HEAD(name, type)						\
 struct name {								\
 	struct type *stqh_first;/* first element */			\
 	struct type **stqh_last;/* addr of last next element */		\
 }
 
-#define STAILQ_HEAD_INITIALIZER(head)					\
+#define	STAILQ_HEAD_INITIALIZER(head)					\
 	{ NULL, &(head).stqh_first }
 
-#define STAILQ_ENTRY(type)						\
+#define	STAILQ_ENTRY(type)						\
 struct {								\
 	struct type *stqe_next;	/* next element */			\
 }
@@ -202,74 +269,116 @@ struct {								\
 /*
  * Singly-linked Tail queue functions.
  */
-#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL)
+#define	STAILQ_CONCAT(head1, head2) do {				\
+	if (!STAILQ_EMPTY((head2))) {					\
+		*(head1)->stqh_last = (head2)->stqh_first;		\
+		(head1)->stqh_last = (head2)->stqh_last;		\
+		STAILQ_INIT((head2));					\
+	}								\
+} while (0)
+
+#define	STAILQ_EMPTY(head)	((head)->stqh_first == NULL)
+
+#define	STAILQ_FIRST(head)	((head)->stqh_first)
+
+#define	STAILQ_FOREACH(var, head, field)				\
+	for((var) = STAILQ_FIRST((head));				\
+	   (var);							\
+	   (var) = STAILQ_NEXT((var), field))
+
+
+#define	STAILQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = STAILQ_FIRST((head));				\
+	    (var) && ((tvar) = STAILQ_NEXT((var), field), 1);		\
+	    (var) = (tvar))
 
 #define	STAILQ_INIT(head) do {						\
-	(head)->stqh_first = NULL;					\
-	(head)->stqh_last = &(head)->stqh_first;			\
+	STAILQ_FIRST((head)) = NULL;					\
+	(head)->stqh_last = &STAILQ_FIRST((head));			\
 } while (0)
 
-#define STAILQ_FIRST(head)	((head)->stqh_first)
-#define STAILQ_LAST(head)	(*(head)->stqh_last)
+#define	STAILQ_INSERT_AFTER(head, tqelm, elm, field) do {		\
+	if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\
+		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
+	STAILQ_NEXT((tqelm), field) = (elm);				\
+} while (0)
 
-#define STAILQ_INSERT_HEAD(head, elm, field) do {			\
-	if (((elm)->field.stqe_next = (head)->stqh_first) == NULL)	\
-		(head)->stqh_last = &(elm)->field.stqe_next;		\
-	(head)->stqh_first = (elm);					\
+#define	STAILQ_INSERT_HEAD(head, elm, field) do {			\
+	if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL)	\
+		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
+	STAILQ_FIRST((head)) = (elm);					\
 } while (0)
 
-#define STAILQ_INSERT_TAIL(head, elm, field) do {			\
-	(elm)->field.stqe_next = NULL;					\
+#define	STAILQ_INSERT_TAIL(head, elm, field) do {			\
+	STAILQ_NEXT((elm), field) = NULL;				\
 	*(head)->stqh_last = (elm);					\
-	(head)->stqh_last = &(elm)->field.stqe_next;			\
+	(head)->stqh_last = &STAILQ_NEXT((elm), field);			\
 } while (0)
 
-#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do {		\
-	if (((elm)->field.stqe_next = (tqelm)->field.stqe_next) == NULL)\
-		(head)->stqh_last = &(elm)->field.stqe_next;		\
-	(tqelm)->field.stqe_next = (elm);				\
-} while (0)
+#define	STAILQ_LAST(head, type, field)					\
+	(STAILQ_EMPTY((head)) ?						\
+		NULL :							\
+	        ((struct type *)(void *)				\
+		((char *)((head)->stqh_last) - __offsetof(struct type, field))))
 
-#define STAILQ_NEXT(elm, field)	((elm)->field.stqe_next)
+#define	STAILQ_NEXT(elm, field)	((elm)->field.stqe_next)
 
-#define STAILQ_REMOVE_HEAD(head, field) do {				\
-	if (((head)->stqh_first =					\
-	     (head)->stqh_first->field.stqe_next) == NULL)		\
-		(head)->stqh_last = &(head)->stqh_first;		\
+#define	STAILQ_REMOVE(head, elm, type, field) do {			\
+	if (STAILQ_FIRST((head)) == (elm)) {				\
+		STAILQ_REMOVE_HEAD((head), field);			\
+	}								\
+	else {								\
+		struct type *curelm = STAILQ_FIRST((head));		\
+		while (STAILQ_NEXT(curelm, field) != (elm))		\
+			curelm = STAILQ_NEXT(curelm, field);		\
+		STAILQ_REMOVE_AFTER(head, curelm, field);		\
+	}								\
+	TRASHIT((elm)->field.stqe_next);				\
 } while (0)
 
-#define STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do {			\
-	if (((head)->stqh_first = (elm)->field.stqe_next) == NULL)	\
-		(head)->stqh_last = &(head)->stqh_first;		\
+#define	STAILQ_REMOVE_HEAD(head, field) do {				\
+	if ((STAILQ_FIRST((head)) =					\
+	     STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL)		\
+		(head)->stqh_last = &STAILQ_FIRST((head));		\
 } while (0)
 
+#define STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do {                 \
+       if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL) \
+               (head)->stqh_last = &STAILQ_FIRST((head));              \
+} while (0)
 
-#define STAILQ_REMOVE(head, elm, type, field) do {			\
-	if ((head)->stqh_first == (elm)) {				\
-		STAILQ_REMOVE_HEAD(head, field);			\
-	}								\
-	else {								\
-		struct type *curelm = (head)->stqh_first;		\
-		while( curelm->field.stqe_next != (elm) )		\
-			curelm = curelm->field.stqe_next;		\
-		if((curelm->field.stqe_next =				\
-		    curelm->field.stqe_next->field.stqe_next) == NULL)	\
-			(head)->stqh_last = &(curelm)->field.stqe_next;	\
-	}								\
+#define STAILQ_REMOVE_AFTER(head, elm, field) do {			\
+	if ((STAILQ_NEXT(elm, field) =					\
+	     STAILQ_NEXT(STAILQ_NEXT(elm, field), field)) == NULL)	\
+		(head)->stqh_last = &STAILQ_NEXT((elm), field);		\
+} while (0)
+
+#define STAILQ_SWAP(head1, head2, type) do {				\
+	struct type *swap_first = STAILQ_FIRST(head1);			\
+	struct type **swap_last = (head1)->stqh_last;			\
+	STAILQ_FIRST(head1) = STAILQ_FIRST(head2);			\
+	(head1)->stqh_last = (head2)->stqh_last;			\
+	STAILQ_FIRST(head2) = swap_first;				\
+	(head2)->stqh_last = swap_last;					\
+	if (STAILQ_EMPTY(head1))					\
+		(head1)->stqh_last = &STAILQ_FIRST(head1);		\
+	if (STAILQ_EMPTY(head2))					\
+		(head2)->stqh_last = &STAILQ_FIRST(head2);		\
 } while (0)
 
+
 /*
- * List definitions.
+ * List declarations.
  */
-#define LIST_HEAD(name, type)						\
+#define	LIST_HEAD(name, type)						\
 struct name {								\
 	struct type *lh_first;	/* first element */			\
 }
 
-#define LIST_HEAD_INITIALIZER(head)					\
+#define	LIST_HEAD_INITIALIZER(head)					\
 	{ NULL }
 
-#define LIST_ENTRY(type)						\
+#define	LIST_ENTRY(type)						\
 struct {								\
 	struct type *le_next;	/* next element */			\
 	struct type **le_prev;	/* address of previous next element */	\
@@ -279,134 +388,242 @@ struct {								\
  * List functions.
  */
 
-#define	LIST_EMPTY(head) ((head)->lh_first == NULL)
+#if (defined(_KERNEL) && defined(INVARIANTS)) || defined(QUEUE_MACRO_DEBUG)
+#define	QMD_LIST_CHECK_HEAD(head, field) do {				\
+	if (LIST_FIRST((head)) != NULL &&				\
+	    LIST_FIRST((head))->field.le_prev !=			\
+	     &LIST_FIRST((head)))					\
+		panic("Bad list head %p first->prev != head", (head));	\
+} while (0)
+
+#define	QMD_LIST_CHECK_NEXT(elm, field) do {				\
+	if (LIST_NEXT((elm), field) != NULL &&				\
+	    LIST_NEXT((elm), field)->field.le_prev !=			\
+	     &((elm)->field.le_next))					\
+	     	panic("Bad link elm %p next->prev != elm", (elm));	\
+} while (0)
+
+#define	QMD_LIST_CHECK_PREV(elm, field) do {				\
+	if (*(elm)->field.le_prev != (elm))				\
+		panic("Bad link elm %p prev->next != elm", (elm));	\
+} while (0)
+#else
+#define	QMD_LIST_CHECK_HEAD(head, field)
+#define	QMD_LIST_CHECK_NEXT(elm, field)
+#define	QMD_LIST_CHECK_PREV(elm, field)
+#endif /* (_KERNEL && INVARIANTS) || QUEUE_MACRO_DEBUG */
+
+#define	LIST_EMPTY(head)	((head)->lh_first == NULL)
 
-#define LIST_FIRST(head)	((head)->lh_first)
+#define	LIST_FIRST(head)	((head)->lh_first)
 
-#define LIST_FOREACH(var, head, field)					\
-	for((var) = (head)->lh_first; (var); (var) = (var)->field.le_next)
+#define	LIST_FOREACH(var, head, field)					\
+	for ((var) = LIST_FIRST((head));				\
+	    (var);							\
+	    (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))
 
 #define	LIST_INIT(head) do {						\
-	(head)->lh_first = NULL;					\
+	LIST_FIRST((head)) = NULL;					\
 } while (0)
 
-#define LIST_INSERT_AFTER(listelm, elm, field) do {			\
-	if (((elm)->field.le_next = (listelm)->field.le_next) != NULL)	\
-		(listelm)->field.le_next->field.le_prev =		\
-		    &(elm)->field.le_next;				\
-	(listelm)->field.le_next = (elm);				\
-	(elm)->field.le_prev = &(listelm)->field.le_next;		\
+#define	LIST_INSERT_AFTER(listelm, elm, field) do {			\
+	QMD_LIST_CHECK_NEXT(listelm, field);				\
+	if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\
+		LIST_NEXT((listelm), field)->field.le_prev =		\
+		    &LIST_NEXT((elm), field);				\
+	LIST_NEXT((listelm), field) = (elm);				\
+	(elm)->field.le_prev = &LIST_NEXT((listelm), field);		\
 } while (0)
 
-#define LIST_INSERT_BEFORE(listelm, elm, field) do {			\
+#define	LIST_INSERT_BEFORE(listelm, elm, field) do {			\
+	QMD_LIST_CHECK_PREV(listelm, field);				\
 	(elm)->field.le_prev = (listelm)->field.le_prev;		\
-	(elm)->field.le_next = (listelm);				\
+	LIST_NEXT((elm), field) = (listelm);				\
 	*(listelm)->field.le_prev = (elm);				\
-	(listelm)->field.le_prev = &(elm)->field.le_next;		\
+	(listelm)->field.le_prev = &LIST_NEXT((elm), field);		\
 } while (0)
 
-#define LIST_INSERT_HEAD(head, elm, field) do {				\
-	if (((elm)->field.le_next = (head)->lh_first) != NULL)		\
-		(head)->lh_first->field.le_prev = &(elm)->field.le_next;\
-	(head)->lh_first = (elm);					\
-	(elm)->field.le_prev = &(head)->lh_first;			\
+#define	LIST_INSERT_HEAD(head, elm, field) do {				\
+	QMD_LIST_CHECK_HEAD((head), field);				\
+	if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL)	\
+		LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\
+	LIST_FIRST((head)) = (elm);					\
+	(elm)->field.le_prev = &LIST_FIRST((head));			\
 } while (0)
 
-#define LIST_NEXT(elm, field)	((elm)->field.le_next)
+#define	LIST_NEXT(elm, field)	((elm)->field.le_next)
 
-#define LIST_REMOVE(elm, field) do {					\
-	if ((elm)->field.le_next != NULL)				\
-		(elm)->field.le_next->field.le_prev = 			\
+#define	LIST_REMOVE(elm, field) do {					\
+	QMD_LIST_CHECK_NEXT(elm, field);				\
+	QMD_LIST_CHECK_PREV(elm, field);				\
+	if (LIST_NEXT((elm), field) != NULL)				\
+		LIST_NEXT((elm), field)->field.le_prev = 		\
 		    (elm)->field.le_prev;				\
-	*(elm)->field.le_prev = (elm)->field.le_next;			\
+	*(elm)->field.le_prev = LIST_NEXT((elm), field);		\
+	TRASHIT((elm)->field.le_next);					\
+	TRASHIT((elm)->field.le_prev);					\
+} while (0)
+
+#define LIST_SWAP(head1, head2, type, field) do {			\
+	struct type *swap_tmp = LIST_FIRST((head1));			\
+	LIST_FIRST((head1)) = LIST_FIRST((head2));			\
+	LIST_FIRST((head2)) = swap_tmp;					\
+	if ((swap_tmp = LIST_FIRST((head1))) != NULL)			\
+		swap_tmp->field.le_prev = &LIST_FIRST((head1));		\
+	if ((swap_tmp = LIST_FIRST((head2))) != NULL)			\
+		swap_tmp->field.le_prev = &LIST_FIRST((head2));		\
 } while (0)
 
 /*
- * Tail queue definitions.
+ * Tail queue declarations.
  */
-#define TAILQ_HEAD(name, type)						\
+#define	TAILQ_HEAD(name, type)						\
 struct name {								\
 	struct type *tqh_first;	/* first element */			\
 	struct type **tqh_last;	/* addr of last next element */		\
+	TRACEBUF							\
 }
 
-#define TAILQ_HEAD_INITIALIZER(head)					\
+#define	TAILQ_HEAD_INITIALIZER(head)					\
 	{ NULL, &(head).tqh_first }
 
-#define TAILQ_ENTRY(type)						\
+#define	TAILQ_ENTRY(type)						\
 struct {								\
 	struct type *tqe_next;	/* next element */			\
 	struct type **tqe_prev;	/* address of previous next element */	\
+	TRACEBUF							\
 }
 
 /*
  * Tail queue functions.
  */
-#define	TAILQ_EMPTY(head) ((head)->tqh_first == NULL)
+#define	TAILQ_CONCAT(head1, head2, field) do {				\
+	if (!TAILQ_EMPTY(head2)) {					\
+		*(head1)->tqh_last = (head2)->tqh_first;		\
+		(head2)->tqh_first->field.tqe_prev = (head1)->tqh_last;	\
+		(head1)->tqh_last = (head2)->tqh_last;			\
+		TAILQ_INIT((head2));					\
+		QMD_TRACE_HEAD(head1);					\
+		QMD_TRACE_HEAD(head2);					\
+	}								\
+} while (0)
 
-#define TAILQ_FOREACH(var, head, field)					\
-	for (var = TAILQ_FIRST(head); var; var = TAILQ_NEXT(var, field))
+#define	TAILQ_EMPTY(head)	((head)->tqh_first == NULL)
 
-#define TAILQ_FOREACH_REVERSE(var, head, field, headname)					\
-	for (var = TAILQ_LAST(head, headname);		       \
-	       var; var = TAILQ_PREV(var, headname, field))
+#define	TAILQ_FIRST(head)	((head)->tqh_first)
 
-#define	TAILQ_FIRST(head) ((head)->tqh_first)
+#define	TAILQ_FOREACH(var, head, field)					\
+	for ((var) = TAILQ_FIRST((head));				\
+	    (var);							\
+	    (var) = TAILQ_NEXT((var), field))
 
-#define	TAILQ_LAST(head, headname) \
-	(*(((struct headname *)((head)->tqh_last))->tqh_last))
+#define	TAILQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = TAILQ_FIRST((head));				\
+	    (var) && ((tvar) = TAILQ_NEXT((var), field), 1);		\
+	    (var) = (tvar))
 
-#define	TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
+#define	TAILQ_FOREACH_REVERSE(var, head, headname, field)		\
+	for ((var) = TAILQ_LAST((head), headname);			\
+	    (var);							\
+	    (var) = TAILQ_PREV((var), headname, field))
 
-#define TAILQ_PREV(elm, headname, field) \
-	(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+#define	TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar)	\
+	for ((var) = TAILQ_LAST((head), headname);			\
+	    (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1);	\
+	    (var) = (tvar))
 
 #define	TAILQ_INIT(head) do {						\
-	(head)->tqh_first = NULL;					\
-	(head)->tqh_last = &(head)->tqh_first;				\
+	TAILQ_FIRST((head)) = NULL;					\
+	(head)->tqh_last = &TAILQ_FIRST((head));			\
+	QMD_TRACE_HEAD(head);						\
 } while (0)
 
-#define TAILQ_INSERT_HEAD(head, elm, field) do {			\
-	if (((elm)->field.tqe_next = (head)->tqh_first) != NULL)	\
-		(head)->tqh_first->field.tqe_prev =			\
-		    &(elm)->field.tqe_next;				\
-	else								\
-		(head)->tqh_last = &(elm)->field.tqe_next;		\
-	(head)->tqh_first = (elm);					\
-	(elm)->field.tqe_prev = &(head)->tqh_first;			\
+#define	TAILQ_INSERT_AFTER(head, listelm, elm, field) do {		\
+	if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\
+		TAILQ_NEXT((elm), field)->field.tqe_prev = 		\
+		    &TAILQ_NEXT((elm), field);				\
+	else {								\
+		(head)->tqh_last = &TAILQ_NEXT((elm), field);		\
+		QMD_TRACE_HEAD(head);					\
+	}								\
+	TAILQ_NEXT((listelm), field) = (elm);				\
+	(elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field);		\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+	QMD_TRACE_ELEM(&listelm->field);				\
 } while (0)
 
-#define TAILQ_INSERT_TAIL(head, elm, field) do {			\
-	(elm)->field.tqe_next = NULL;					\
-	(elm)->field.tqe_prev = (head)->tqh_last;			\
-	*(head)->tqh_last = (elm);					\
-	(head)->tqh_last = &(elm)->field.tqe_next;			\
+#define	TAILQ_INSERT_BEFORE(listelm, elm, field) do {			\
+	(elm)->field.tqe_prev = (listelm)->field.tqe_prev;		\
+	TAILQ_NEXT((elm), field) = (listelm);				\
+	*(listelm)->field.tqe_prev = (elm);				\
+	(listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field);		\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+	QMD_TRACE_ELEM(&listelm->field);				\
 } while (0)
 
-#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do {		\
-	if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
-		(elm)->field.tqe_next->field.tqe_prev = 		\
-		    &(elm)->field.tqe_next;				\
+#define	TAILQ_INSERT_HEAD(head, elm, field) do {			\
+	if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL)	\
+		TAILQ_FIRST((head))->field.tqe_prev =			\
+		    &TAILQ_NEXT((elm), field);				\
 	else								\
-		(head)->tqh_last = &(elm)->field.tqe_next;		\
-	(listelm)->field.tqe_next = (elm);				\
-	(elm)->field.tqe_prev = &(listelm)->field.tqe_next;		\
+		(head)->tqh_last = &TAILQ_NEXT((elm), field);		\
+	TAILQ_FIRST((head)) = (elm);					\
+	(elm)->field.tqe_prev = &TAILQ_FIRST((head));			\
+	QMD_TRACE_HEAD(head);						\
+	QMD_TRACE_ELEM(&(elm)->field);					\
 } while (0)
 
-#define TAILQ_INSERT_BEFORE(listelm, elm, field) do {			\
-	(elm)->field.tqe_prev = (listelm)->field.tqe_prev;		\
-	(elm)->field.tqe_next = (listelm);				\
-	*(listelm)->field.tqe_prev = (elm);				\
-	(listelm)->field.tqe_prev = &(elm)->field.tqe_next;		\
+#define	TAILQ_INSERT_TAIL(head, elm, field) do {			\
+	TAILQ_NEXT((elm), field) = NULL;				\
+	(elm)->field.tqe_prev = (head)->tqh_last;			\
+	*(head)->tqh_last = (elm);					\
+	(head)->tqh_last = &TAILQ_NEXT((elm), field);			\
+	QMD_TRACE_HEAD(head);						\
+	QMD_TRACE_ELEM(&(elm)->field);					\
 } while (0)
 
-#define TAILQ_REMOVE(head, elm, field) do {				\
-	if (((elm)->field.tqe_next) != NULL)				\
-		(elm)->field.tqe_next->field.tqe_prev = 		\
+#define	TAILQ_LAST(head, headname)					\
+	(*(((struct headname *)((head)->tqh_last))->tqh_last))
+
+#define	TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
+
+#define	TAILQ_PREV(elm, headname, field)				\
+	(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+
+#define	TAILQ_REMOVE(head, elm, field) do {				\
+	if ((TAILQ_NEXT((elm), field)) != NULL)				\
+		TAILQ_NEXT((elm), field)->field.tqe_prev = 		\
 		    (elm)->field.tqe_prev;				\
-	else								\
+	else {								\
 		(head)->tqh_last = (elm)->field.tqe_prev;		\
-	*(elm)->field.tqe_prev = (elm)->field.tqe_next;			\
+		QMD_TRACE_HEAD(head);					\
+	}								\
+	*(elm)->field.tqe_prev = TAILQ_NEXT((elm), field);		\
+	TRASHIT((elm)->field.tqe_next);					\
+	TRASHIT((elm)->field.tqe_prev);					\
+	QMD_TRACE_ELEM(&(elm)->field);					\
+} while (0)
+
+#define TAILQ_SWAP(head1, head2, type, field) do {                      \
+	struct type *swap_first = (head1)->tqh_first;                   \
+	struct type **swap_last = (head1)->tqh_last;                    \
+	(head1)->tqh_first = (head2)->tqh_first;                        \
+	(head1)->tqh_last = (head2)->tqh_last;                          \
+	(head2)->tqh_first = swap_first;                                \
+	(head2)->tqh_last = swap_last;                                  \
+	if ((swap_first = (head1)->tqh_first) != NULL)                  \
+		swap_first->field.tqe_prev = &(head1)->tqh_first;       \
+	else                                                            \
+		(head1)->tqh_last = &(head1)->tqh_first;                \
+	if ((swap_first = (head2)->tqh_first) != NULL)                  \
+		swap_first->field.tqe_prev = &(head2)->tqh_first;       \
+	else                                                            \
+		(head2)->tqh_last = &(head2)->tqh_first;                \
 } while (0)
 
 /*
@@ -500,7 +717,7 @@ struct {								\
 		    (elm)->field.cqe_next;				\
 } while (0)
 
-#ifdef KERNEL
+#ifdef _KERNEL
 
 #if NOTFB31
 
@@ -514,12 +731,13 @@ struct quehead {
 	struct quehead *qh_rlink;
 };
 
-#ifdef	__GNUC__
+#ifdef __GNUC__
 
 static __inline void
 insque(void *a, void *b)
 {
-	struct quehead *element = a, *head = b;
+	struct quehead *element = (struct quehead *)a,
+		 *head = (struct quehead *)b;
 
 	element->qh_link = head->qh_link;
 	element->qh_rlink = head;
@@ -530,7 +748,7 @@ insque(void *a, void *b)
 static __inline void
 remque(void *a)
 {
-	struct quehead *element = a;
+	struct quehead *element = (struct quehead *)a;
 
 	element->qh_link->qh_rlink = element->qh_rlink;
 	element->qh_rlink->qh_link = element->qh_link;
@@ -545,6 +763,6 @@ void	remque(void *a);
 #endif /* __GNUC__ */
 
 #endif
-#endif /* KERNEL */
+#endif /* _KERNEL */
 
 #endif /* !_SYS_QUEUE_H_ */