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-rw-r--r--misc/sys/queue.h441
1 files changed, 389 insertions, 52 deletions
diff --git a/misc/sys/queue.h b/misc/sys/queue.h
index 5b6e2a0..d709d48 100644
--- a/misc/sys/queue.h
+++ b/misc/sys/queue.h
@@ -10,7 +10,7 @@
* 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.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. 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.
*
@@ -26,29 +26,46 @@
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
- * @(#)queue.h 8.3 (Berkeley) 12/13/93
+ * @(#)queue.h 8.5 (Berkeley) 8/20/94
*/
-#ifndef _SYS_QUEUE_H
-#define _SYS_QUEUE_H 1
+#ifndef _SYS_QUEUE_H_
+#define _SYS_QUEUE_H_
/*
- * This file defines three types of data structures: lists, tail queues,
- * and circular queues.
+ * This file defines five types of data structures: singly-linked lists,
+ * lists, simple queues, 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 the expense of O(n) removal for arbitrary elements. New
+ * elements can be added to the list after an existing element or at the
+ * head of the list. Elements being removed from the head of the list
+ * should use the explicit macro for this purpose for optimum
+ * efficiency. A singly-linked list may only be traversed in the forward
+ * direction. Singly-linked lists are ideal for applications with large
+ * datasets and few or no removals or for implementing a LIFO queue.
*
* A list is headed by a single forward pointer (or an array of forward
* pointers for a hash table header). 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 after
- * an existing element or at the head of the list. A list may only be
- * traversed in the forward direction.
+ * traverse the list. New elements can be added to the list before
+ * or after an existing element or at the head of the list. A list
+ * may only be traversed in the forward direction.
+ *
+ * A simple queue is headed by a pair of pointers, one the head of the
+ * list and the other to the tail of the list. The elements are singly
+ * linked to save space, so elements can only be removed from the
+ * head of the list. New elements can be added to the list after
+ * an existing element, at the head of the list, or at the end of the
+ * list. A simple queue may only be traversed in the forward direction.
*
* A tail 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 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.
+ * 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 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
@@ -64,12 +81,15 @@
/*
* List definitions.
*/
-#define LIST_HEAD(name, type) \
+#define LIST_HEAD(name, type) \
struct name { \
struct type *lh_first; /* first element */ \
}
-#define LIST_ENTRY(type) \
+#define LIST_HEAD_INITIALIZER(head) \
+ { NULL }
+
+#define LIST_ENTRY(type) \
struct { \
struct type *le_next; /* next element */ \
struct type **le_prev; /* address of previous next element */ \
@@ -78,73 +98,315 @@ struct { \
/*
* List functions.
*/
-#define LIST_INIT(head) { \
+#define LIST_INIT(head) do { \
(head)->lh_first = NULL; \
-}
+} while (/*CONSTCOND*/0)
-#define LIST_INSERT_AFTER(listelm, elm, field) { \
+#define LIST_INSERT_AFTER(listelm, elm, field) do { \
+ QUEUEDEBUG_LIST_OP((listelm), field) \
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; \
-}
+} while (/*CONSTCOND*/0)
-#define LIST_INSERT_HEAD(head, elm, field) { \
+#define LIST_INSERT_BEFORE(listelm, elm, field) do { \
+ QUEUEDEBUG_LIST_OP((listelm), field) \
+ (elm)->field.le_prev = (listelm)->field.le_prev; \
+ (elm)->field.le_next = (listelm); \
+ *(listelm)->field.le_prev = (elm); \
+ (listelm)->field.le_prev = &(elm)->field.le_next; \
+} while (/*CONSTCOND*/0)
+
+#define LIST_INSERT_HEAD(head, elm, field) do { \
+ QUEUEDEBUG_LIST_INSERT_HEAD((head), (elm), field) \
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; \
-}
+} while (/*CONSTCOND*/0)
-#define LIST_REMOVE(elm, field) { \
+#define LIST_REMOVE(elm, field) do { \
+ QUEUEDEBUG_LIST_OP((elm), field) \
if ((elm)->field.le_next != NULL) \
(elm)->field.le_next->field.le_prev = \
(elm)->field.le_prev; \
*(elm)->field.le_prev = (elm)->field.le_next; \
+ QUEUEDEBUG_LIST_POSTREMOVE((elm), field) \
+} while (/*CONSTCOND*/0)
+
+#define LIST_FOREACH(var, head, field) \
+ for ((var) = ((head)->lh_first); \
+ (var); \
+ (var) = ((var)->field.le_next))
+
+/*
+ * List access methods.
+ */
+#define LIST_EMPTY(head) ((head)->lh_first == NULL)
+#define LIST_FIRST(head) ((head)->lh_first)
+#define LIST_NEXT(elm, field) ((elm)->field.le_next)
+
+
+/*
+ * Singly-linked List definitions.
+ */
+#define SLIST_HEAD(name, type) \
+struct name { \
+ struct type *slh_first; /* first element */ \
+}
+
+#define SLIST_HEAD_INITIALIZER(head) \
+ { NULL }
+
+#define SLIST_ENTRY(type) \
+struct { \
+ struct type *sle_next; /* next element */ \
+}
+
+/*
+ * Singly-linked List functions.
+ */
+#define SLIST_INIT(head) do { \
+ (head)->slh_first = NULL; \
+} while (/*CONSTCOND*/0)
+
+#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
+ (elm)->field.sle_next = (slistelm)->field.sle_next; \
+ (slistelm)->field.sle_next = (elm); \
+} while (/*CONSTCOND*/0)
+
+#define SLIST_INSERT_HEAD(head, elm, field) do { \
+ (elm)->field.sle_next = (head)->slh_first; \
+ (head)->slh_first = (elm); \
+} while (/*CONSTCOND*/0)
+
+#define SLIST_REMOVE_HEAD(head, field) do { \
+ (head)->slh_first = (head)->slh_first->field.sle_next; \
+} while (/*CONSTCOND*/0)
+
+#define SLIST_REMOVE(head, elm, type, field) do { \
+ if ((head)->slh_first == (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; \
+ } \
+} while (/*CONSTCOND*/0)
+
+#define SLIST_FOREACH(var, head, field) \
+ for((var) = (head)->slh_first; (var); (var) = (var)->field.sle_next)
+
+/*
+ * Singly-linked List access methods.
+ */
+#define SLIST_EMPTY(head) ((head)->slh_first == NULL)
+#define SLIST_FIRST(head) ((head)->slh_first)
+#define SLIST_NEXT(elm, field) ((elm)->field.sle_next)
+
+
+/*
+ * Singly-linked Tail queue declarations.
+ */
+#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) \
+ { NULL, &(head).stqh_first }
+
+#define STAILQ_ENTRY(type) \
+struct { \
+ struct type *stqe_next; /* next element */ \
+}
+
+/*
+ * Singly-linked Tail queue functions.
+ */
+#define STAILQ_INIT(head) do { \
+ (head)->stqh_first = NULL; \
+ (head)->stqh_last = &(head)->stqh_first; \
+} while (/*CONSTCOND*/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); \
+} while (/*CONSTCOND*/0)
+
+#define STAILQ_INSERT_TAIL(head, elm, field) do { \
+ (elm)->field.stqe_next = NULL; \
+ *(head)->stqh_last = (elm); \
+ (head)->stqh_last = &(elm)->field.stqe_next; \
+} while (/*CONSTCOND*/0)
+
+#define STAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
+ if (((elm)->field.stqe_next = (listelm)->field.stqe_next) == NULL)\
+ (head)->stqh_last = &(elm)->field.stqe_next; \
+ (listelm)->field.stqe_next = (elm); \
+} while (/*CONSTCOND*/0)
+
+#define STAILQ_REMOVE_HEAD(head, field) do { \
+ if (((head)->stqh_first = (head)->stqh_first->field.stqe_next) == NULL) \
+ (head)->stqh_last = &(head)->stqh_first; \
+} while (/*CONSTCOND*/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; \
+ } \
+} while (/*CONSTCOND*/0)
+
+#define STAILQ_FOREACH(var, head, field) \
+ for ((var) = ((head)->stqh_first); \
+ (var); \
+ (var) = ((var)->field.stqe_next))
+
+/*
+ * Singly-linked Tail queue access methods.
+ */
+#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL)
+#define STAILQ_FIRST(head) ((head)->stqh_first)
+#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next)
+
+
+/*
+ * Simple queue definitions.
+ */
+#define SIMPLEQ_HEAD(name, type) \
+struct name { \
+ struct type *sqh_first; /* first element */ \
+ struct type **sqh_last; /* addr of last next element */ \
+}
+
+#define SIMPLEQ_HEAD_INITIALIZER(head) \
+ { NULL, &(head).sqh_first }
+
+#define SIMPLEQ_ENTRY(type) \
+struct { \
+ struct type *sqe_next; /* next element */ \
}
/*
+ * Simple queue functions.
+ */
+#define SIMPLEQ_INIT(head) do { \
+ (head)->sqh_first = NULL; \
+ (head)->sqh_last = &(head)->sqh_first; \
+} while (/*CONSTCOND*/0)
+
+#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \
+ if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \
+ (head)->sqh_last = &(elm)->field.sqe_next; \
+ (head)->sqh_first = (elm); \
+} while (/*CONSTCOND*/0)
+
+#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \
+ (elm)->field.sqe_next = NULL; \
+ *(head)->sqh_last = (elm); \
+ (head)->sqh_last = &(elm)->field.sqe_next; \
+} while (/*CONSTCOND*/0)
+
+#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
+ if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
+ (head)->sqh_last = &(elm)->field.sqe_next; \
+ (listelm)->field.sqe_next = (elm); \
+} while (/*CONSTCOND*/0)
+
+#define SIMPLEQ_REMOVE_HEAD(head, field) do { \
+ if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \
+ (head)->sqh_last = &(head)->sqh_first; \
+} while (/*CONSTCOND*/0)
+
+#define SIMPLEQ_REMOVE(head, elm, type, field) do { \
+ if ((head)->sqh_first == (elm)) { \
+ SIMPLEQ_REMOVE_HEAD((head), field); \
+ } else { \
+ struct type *curelm = (head)->sqh_first; \
+ while (curelm->field.sqe_next != (elm)) \
+ curelm = curelm->field.sqe_next; \
+ if ((curelm->field.sqe_next = \
+ curelm->field.sqe_next->field.sqe_next) == NULL) \
+ (head)->sqh_last = &(curelm)->field.sqe_next; \
+ } \
+} while (/*CONSTCOND*/0)
+
+#define SIMPLEQ_FOREACH(var, head, field) \
+ for ((var) = ((head)->sqh_first); \
+ (var); \
+ (var) = ((var)->field.sqe_next))
+
+/*
+ * Simple queue access methods.
+ */
+#define SIMPLEQ_EMPTY(head) ((head)->sqh_first == NULL)
+#define SIMPLEQ_FIRST(head) ((head)->sqh_first)
+#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next)
+
+
+/*
* Tail queue definitions.
*/
-#define TAILQ_HEAD(name, type) \
+#define _TAILQ_HEAD(name, type, qual) \
struct name { \
- struct type *tqh_first; /* first element */ \
- struct type **tqh_last; /* addr of last next element */ \
+ qual type *tqh_first; /* first element */ \
+ qual type *qual *tqh_last; /* addr of last next element */ \
}
+#define TAILQ_HEAD(name, type) _TAILQ_HEAD(name, struct type,)
+
+#define TAILQ_HEAD_INITIALIZER(head) \
+ { NULL, &(head).tqh_first }
-#define TAILQ_ENTRY(type) \
+#define _TAILQ_ENTRY(type, qual) \
struct { \
- struct type *tqe_next; /* next element */ \
- struct type **tqe_prev; /* address of previous next element */ \
+ qual type *tqe_next; /* next element */ \
+ qual type *qual *tqe_prev; /* address of previous next element */\
}
+#define TAILQ_ENTRY(type) _TAILQ_ENTRY(struct type,)
/*
* Tail queue functions.
*/
-#define TAILQ_INIT(head) { \
+#define TAILQ_INIT(head) do { \
(head)->tqh_first = NULL; \
(head)->tqh_last = &(head)->tqh_first; \
-}
+} while (/*CONSTCOND*/0)
-#define TAILQ_INSERT_HEAD(head, elm, field) { \
+#define TAILQ_INSERT_HEAD(head, elm, field) do { \
+ QUEUEDEBUG_TAILQ_INSERT_HEAD((head), (elm), field) \
if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \
- (elm)->field.tqe_next->field.tqe_prev = \
+ (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; \
-}
+} while (/*CONSTCOND*/0)
-#define TAILQ_INSERT_TAIL(head, elm, field) { \
+#define TAILQ_INSERT_TAIL(head, elm, field) do { \
+ QUEUEDEBUG_TAILQ_INSERT_TAIL((head), (elm), field) \
(elm)->field.tqe_next = NULL; \
(elm)->field.tqe_prev = (head)->tqh_last; \
*(head)->tqh_last = (elm); \
(head)->tqh_last = &(elm)->field.tqe_next; \
-}
+} while (/*CONSTCOND*/0)
-#define TAILQ_INSERT_AFTER(head, listelm, elm, field) { \
+#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
+ QUEUEDEBUG_TAILQ_OP((listelm), field) \
if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
(elm)->field.tqe_next->field.tqe_prev = \
&(elm)->field.tqe_next; \
@@ -152,27 +414,64 @@ struct { \
(head)->tqh_last = &(elm)->field.tqe_next; \
(listelm)->field.tqe_next = (elm); \
(elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
-}
+} while (/*CONSTCOND*/0)
+
+#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \
+ QUEUEDEBUG_TAILQ_OP((listelm), field) \
+ (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; \
+} while (/*CONSTCOND*/0)
-#define TAILQ_REMOVE(head, elm, field) { \
+#define TAILQ_REMOVE(head, elm, field) do { \
+ QUEUEDEBUG_TAILQ_PREREMOVE((head), (elm), field) \
+ QUEUEDEBUG_TAILQ_OP((elm), field) \
if (((elm)->field.tqe_next) != NULL) \
(elm)->field.tqe_next->field.tqe_prev = \
(elm)->field.tqe_prev; \
else \
(head)->tqh_last = (elm)->field.tqe_prev; \
*(elm)->field.tqe_prev = (elm)->field.tqe_next; \
-}
+ QUEUEDEBUG_TAILQ_POSTREMOVE((elm), field); \
+} while (/*CONSTCOND*/0)
+
+#define TAILQ_FOREACH(var, head, field) \
+ for ((var) = ((head)->tqh_first); \
+ (var); \
+ (var) = ((var)->field.tqe_next))
+
+#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \
+ for ((var) = (*(((struct headname *)((head)->tqh_last))->tqh_last)); \
+ (var); \
+ (var) = (*(((struct headname *)((var)->field.tqe_prev))->tqh_last)))
+
+/*
+ * Tail queue access methods.
+ */
+#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL)
+#define TAILQ_FIRST(head) ((head)->tqh_first)
+#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
+
+#define TAILQ_LAST(head, headname) \
+ (*(((struct headname *)((head)->tqh_last))->tqh_last))
+#define TAILQ_PREV(elm, headname, field) \
+ (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+
/*
* Circular queue definitions.
*/
-#define CIRCLEQ_HEAD(name, type) \
+#define CIRCLEQ_HEAD(name, type) \
struct name { \
struct type *cqh_first; /* first element */ \
struct type *cqh_last; /* last element */ \
}
-#define CIRCLEQ_ENTRY(type) \
+#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 */ \
@@ -181,12 +480,14 @@ struct { \
/*
* Circular queue functions.
*/
-#define CIRCLEQ_INIT(head) { \
+#define CIRCLEQ_INIT(head) do { \
(head)->cqh_first = (void *)(head); \
(head)->cqh_last = (void *)(head); \
-}
+} while (/*CONSTCOND*/0)
-#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) { \
+#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
+ QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \
+ QUEUEDEBUG_CIRCLEQ_ELM((head), (listelm), field) \
(elm)->field.cqe_next = (listelm)->field.cqe_next; \
(elm)->field.cqe_prev = (listelm); \
if ((listelm)->field.cqe_next == (void *)(head)) \
@@ -194,9 +495,11 @@ struct { \
else \
(listelm)->field.cqe_next->field.cqe_prev = (elm); \
(listelm)->field.cqe_next = (elm); \
-}
+} while (/*CONSTCOND*/0)
-#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) { \
+#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \
+ QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \
+ QUEUEDEBUG_CIRCLEQ_ELM((head), (listelm), field) \
(elm)->field.cqe_next = (listelm); \
(elm)->field.cqe_prev = (listelm)->field.cqe_prev; \
if ((listelm)->field.cqe_prev == (void *)(head)) \
@@ -204,9 +507,10 @@ struct { \
else \
(listelm)->field.cqe_prev->field.cqe_next = (elm); \
(listelm)->field.cqe_prev = (elm); \
-}
+} while (/*CONSTCOND*/0)
-#define CIRCLEQ_INSERT_HEAD(head, elm, field) { \
+#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \
+ QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \
(elm)->field.cqe_next = (head)->cqh_first; \
(elm)->field.cqe_prev = (void *)(head); \
if ((head)->cqh_last == (void *)(head)) \
@@ -214,9 +518,10 @@ struct { \
else \
(head)->cqh_first->field.cqe_prev = (elm); \
(head)->cqh_first = (elm); \
-}
+} while (/*CONSTCOND*/0)
-#define CIRCLEQ_INSERT_TAIL(head, elm, field) { \
+#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \
+ QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \
(elm)->field.cqe_next = (void *)(head); \
(elm)->field.cqe_prev = (head)->cqh_last; \
if ((head)->cqh_first == (void *)(head)) \
@@ -224,9 +529,11 @@ struct { \
else \
(head)->cqh_last->field.cqe_next = (elm); \
(head)->cqh_last = (elm); \
-}
+} while (/*CONSTCOND*/0)
-#define CIRCLEQ_REMOVE(head, elm, field) { \
+#define CIRCLEQ_REMOVE(head, elm, field) do { \
+ QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \
+ QUEUEDEBUG_CIRCLEQ_ELM((head), (elm), field) \
if ((elm)->field.cqe_next == (void *)(head)) \
(head)->cqh_last = (elm)->field.cqe_prev; \
else \
@@ -237,5 +544,35 @@ struct { \
else \
(elm)->field.cqe_prev->field.cqe_next = \
(elm)->field.cqe_next; \
-}
+ QUEUEDEBUG_CIRCLEQ_POSTREMOVE((elm), field) \
+} while (/*CONSTCOND*/0)
+
+#define CIRCLEQ_FOREACH(var, head, field) \
+ for ((var) = ((head)->cqh_first); \
+ (var) != (const void *)(head); \
+ (var) = ((var)->field.cqe_next))
+
+#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \
+ for ((var) = ((head)->cqh_last); \
+ (var) != (const void *)(head); \
+ (var) = ((var)->field.cqe_prev))
+
+/*
+ * Circular queue access methods.
+ */
+#define CIRCLEQ_EMPTY(head) ((head)->cqh_first == (void *)(head))
+#define CIRCLEQ_FIRST(head) ((head)->cqh_first)
+#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_LOOP_NEXT(head, elm, field) \
+ (((elm)->field.cqe_next == (void *)(head)) \
+ ? ((head)->cqh_first) \
+ : (elm->field.cqe_next))
+#define CIRCLEQ_LOOP_PREV(head, elm, field) \
+ (((elm)->field.cqe_prev == (void *)(head)) \
+ ? ((head)->cqh_last) \
+ : (elm->field.cqe_prev))
+
#endif /* sys/queue.h */
generated by cgit v1.1 at 2024-12-25 10:45:10 +0000