queue.h revision 1450
48N/A/* $NetBSD: queue.h,v 1.42 2005/07/13 15:08:24 wiz Exp $ */
48N/A
48N/A/*
48N/A * Copyright (c) 1991, 1993
48N/A * The Regents of the University of California. All rights reserved.
48N/A *
48N/A * Redistribution and use in source and binary forms, with or without
48N/A * modification, are permitted provided that the following conditions
48N/A * are met:
48N/A * 1. Redistributions of source code must retain the above copyright
48N/A * notice, this list of conditions and the following disclaimer.
48N/A * 2. Redistributions in binary form must reproduce the above copyright
48N/A * notice, this list of conditions and the following disclaimer in the
48N/A * documentation and/or other materials provided with the distribution.
48N/A * 3. Neither the name of the University nor the names of its contributors
48N/A * may be used to endorse or promote products derived from this software
48N/A * without specific prior written permission.
48N/A *
48N/A * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
48N/A * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48N/A * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48N/A * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
48N/A * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48N/A * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
48N/A * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48N/A * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48N/A * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
48N/A * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48N/A * SUCH DAMAGE.
48N/A *
48N/A * @(#)queue.h 8.5 (Berkeley) 8/20/94
48N/A */
70N/A/*
48N/A * Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved.
48N/A */
70N/A
70N/A#ifndef _SYS_QUEUE_H
48N/A#define _SYS_QUEUE_H
48N/A
70N/A#include <sys/note.h>
48N/A
48N/A#ifdef __cplusplus
48N/Aextern "C" {
48N/A#endif
70N/A
48N/A/*
48N/A * This file defines five types of data structures: singly-linked lists,
48N/A * lists, simple queues, tail queues, and circular queues.
48N/A *
70N/A * A singly-linked list is headed by a single forward pointer. The
70N/A * elements are singly linked for minimum space and pointer manipulation
70N/A * overhead at the expense of O(n) removal for arbitrary elements. New
70N/A * elements can be added to the list after an existing element or at the
48N/A * head of the list. Elements being removed from the head of the list
48N/A * should use the explicit macro for this purpose for optimum
70N/A * efficiency. A singly-linked list may only be traversed in the forward
70N/A * direction. Singly-linked lists are ideal for applications with large
70N/A * datasets and few or no removals or for implementing a LIFO queue.
70N/A *
48N/A * A list is headed by a single forward pointer (or an array of forward
70N/A * pointers for a hash table header). The elements are doubly linked
70N/A * so that an arbitrary element can be removed without a need to
70N/A * traverse the list. New elements can be added to the list before
70N/A * or after an existing element or at the head of the list. A list
70N/A * may only be traversed in the forward direction.
70N/A *
70N/A * A simple queue is headed by a pair of pointers, one the head of the
70N/A * list and the other to the tail of the list. The elements are singly
48N/A * linked to save space, so elements can only be removed from the
48N/A * head of the list. New elements can be added to the list after
48N/A * an existing element, at the head of the list, or at the end of the
48N/A * 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 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
* 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.
*/
/*
* List definitions.
*/
#define LIST_HEAD(name, type) \
struct name { \
struct type *lh_first; /* first element */ \
}
#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 */ \
}
/*
* List functions.
*/
#if defined(_KERNEL) && defined(QUEUEDEBUG)
#define QUEUEDEBUG_LIST_INSERT_HEAD(head, elm, field) \
if ((head)->lh_first && \
(head)->lh_first->field.le_prev != &(head)->lh_first) \
panic("LIST_INSERT_HEAD %p %s:%d", (void *)(head), \
__FILE__, __LINE__);
#define QUEUEDEBUG_LIST_OP(elm, field) \
if ((elm)->field.le_next && \
(elm)->field.le_next->field.le_prev != \
&(elm)->field.le_next) \
panic("LIST_* forw %p %s:%d", (void *)(elm), \
__FILE__, __LINE__); \
if (*(elm)->field.le_prev != (elm)) \
panic("LIST_* back %p %s:%d", (void *)(elm), __FILE__, \
__LINE__);
#define QUEUEDEBUG_LIST_POSTREMOVE(elm, field) \
(elm)->field.le_next = (void *)1L; \
(elm)->field.le_prev = (void *)1L;
#else
#define QUEUEDEBUG_LIST_INSERT_HEAD(head, elm, field)
#define QUEUEDEBUG_LIST_OP(elm, field)
#define QUEUEDEBUG_LIST_POSTREMOVE(elm, field)
#endif
#define LIST_INIT(head) do { \
(head)->lh_first = NULL; \
_NOTE(CONSTCOND) \
} while (0)
#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; \
_NOTE(CONSTCOND) \
} while (0)
#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; \
_NOTE(CONSTCOND) \
} while (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; \
_NOTE(CONSTCOND) \
} while (0)
#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) \
_NOTE(CONSTCOND) \
} while (0)
#define LIST_FOREACH(var, head, field) \
for ((var) = ((head)->lh_first); \
(var); \
(var) = ((var)->field.le_next))
#define LIST_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = LIST_FIRST((head)); \
(var) && ((tvar) = LIST_NEXT((var), field), 1); \
(var) = (tvar))
/*
* 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; \
_NOTE(CONSTCOND) \
} while (0)
#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
(elm)->field.sle_next = (slistelm)->field.sle_next; \
(slistelm)->field.sle_next = (elm); \
_NOTE(CONSTCOND) \
} while (0)
#define SLIST_INSERT_HEAD(head, elm, field) do { \
(elm)->field.sle_next = (head)->slh_first; \
(head)->slh_first = (elm); \
_NOTE(CONSTCOND) \
} while (0)
#define SLIST_REMOVE_HEAD(head, field) do { \
(head)->slh_first = (head)->slh_first->field.sle_next; \
_NOTE(CONSTCOND) \
} while (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; \
} \
_NOTE(CONSTCOND) \
} while (0)
#define SLIST_FOREACH(var, head, field) \
for ((var) = (head)->slh_first; (var); (var) = (var)->field.sle_next)
#define SLIST_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = SLIST_FIRST((head)); \
(var) && ((tvar) = SLIST_NEXT((var), field), 1); \
(var) = (tvar))
/*
* 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; \
_NOTE(CONSTCOND) \
} 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); \
_NOTE(CONSTCOND) \
} while (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; \
_NOTE(CONSTCOND) \
} while (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); \
_NOTE(CONSTCOND) \
} while (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; \
_NOTE(CONSTCOND) \
} 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; \
} \
_NOTE(CONSTCOND) \
} while (0)
#define STAILQ_FOREACH(var, head, field) \
for ((var) = ((head)->stqh_first); \
(var); \
(var) = ((var)->field.stqe_next))
#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = STAILQ_FIRST((head)); \
(var) && ((tvar) = STAILQ_NEXT((var), field), 1); \
(var) = (tvar))
/*
* 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; \
_NOTE(CONSTCOND) \
} while (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); \
_NOTE(CONSTCOND) \
} while (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; \
_NOTE(CONSTCOND) \
} while (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); \
_NOTE(CONSTCOND) \
} while (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; \
_NOTE(CONSTCOND) \
} while (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; \
} \
_NOTE(CONSTCOND) \
} while (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) \
struct name { \
type *tqh_first; /* first element */ \
type **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) \
struct { \
type *tqe_next; /* next element */ \
type **tqe_prev; /* address of previous next element */\
}
#define TAILQ_ENTRY(type) _TAILQ_ENTRY(struct type)
/*
* Tail queue functions.
*/
#if defined(_KERNEL) && defined(QUEUEDEBUG)
#define QUEUEDEBUG_TAILQ_INSERT_HEAD(head, elm, field) \
if ((head)->tqh_first && \
(head)->tqh_first->field.tqe_prev != &(head)->tqh_first) \
panic("TAILQ_INSERT_HEAD %p %s:%d", (void *)(head), \
__FILE__, __LINE__);
#define QUEUEDEBUG_TAILQ_INSERT_TAIL(head, elm, field) \
if (*(head)->tqh_last != NULL) \
panic("TAILQ_INSERT_TAIL %p %s:%d", (void *)(head), \
__FILE__, __LINE__);
#define QUEUEDEBUG_TAILQ_OP(elm, field) \
if ((elm)->field.tqe_next && \
(elm)->field.tqe_next->field.tqe_prev != \
&(elm)->field.tqe_next) \
panic("TAILQ_* forw %p %s:%d", (void *)(elm), \
__FILE__, __LINE__);\
if (*(elm)->field.tqe_prev != (elm)) \
panic("TAILQ_* back %p %s:%d", (void *)(elm), \
__FILE__, __LINE__);
#define QUEUEDEBUG_TAILQ_PREREMOVE(head, elm, field) \
if ((elm)->field.tqe_next == NULL && \
(head)->tqh_last != &(elm)->field.tqe_next) \
panic("TAILQ_PREREMOVE head %p elm %p %s:%d", \
(void *)(head), (void *)(elm), __FILE__, __LINE__);
#define QUEUEDEBUG_TAILQ_POSTREMOVE(elm, field) \
(elm)->field.tqe_next = (void *)1L; \
(elm)->field.tqe_prev = (void *)1L;
#else
#define QUEUEDEBUG_TAILQ_INSERT_HEAD(head, elm, field)
#define QUEUEDEBUG_TAILQ_INSERT_TAIL(head, elm, field)
#define QUEUEDEBUG_TAILQ_OP(elm, field)
#define QUEUEDEBUG_TAILQ_PREREMOVE(head, elm, field)
#define QUEUEDEBUG_TAILQ_POSTREMOVE(elm, field)
#endif
#define TAILQ_INIT(head) do { \
(head)->tqh_first = NULL; \
(head)->tqh_last = &(head)->tqh_first; \
_NOTE(CONSTCOND) \
} while (0)
#define TAILQ_INSERT_HEAD(head, elm, field) do { \
QUEUEDEBUG_TAILQ_INSERT_HEAD((head), (elm), field) \
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; \
_NOTE(CONSTCOND) \
} while (0)
#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; \
_NOTE(CONSTCOND) \
} while (0)
#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; \
else \
(head)->tqh_last = &(elm)->field.tqe_next; \
(listelm)->field.tqe_next = (elm); \
(elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
_NOTE(CONSTCOND) \
} while (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; \
_NOTE(CONSTCOND) \
} while (0)
#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); \
_NOTE(CONSTCOND) \
} while (0)
#define TAILQ_FOREACH(var, head, field) \
for ((var) = ((head)->tqh_first); \
(var); \
(var) = ((var)->field.tqe_next))
#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \
for ((var) = TAILQ_FIRST((head)); \
(var) && ((tvar) = TAILQ_NEXT((var), field), 1); \
(var) = (tvar))
#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)))
#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))
/*
* 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) \
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_INIT(head) do { \
(head)->cqh_first = (void *)(head); \
(head)->cqh_last = (void *)(head); \
_NOTE(CONSTCOND) \
} while (0)
#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
(elm)->field.cqe_next = (listelm)->field.cqe_next; \
(elm)->field.cqe_prev = (listelm); \
if ((listelm)->field.cqe_next == (void *)(head)) \
(head)->cqh_last = (elm); \
else \
(listelm)->field.cqe_next->field.cqe_prev = (elm); \
(listelm)->field.cqe_next = (elm); \
_NOTE(CONSTCOND) \
} while (0)
#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \
(elm)->field.cqe_next = (listelm); \
(elm)->field.cqe_prev = (listelm)->field.cqe_prev; \
if ((listelm)->field.cqe_prev == (void *)(head)) \
(head)->cqh_first = (elm); \
else \
(listelm)->field.cqe_prev->field.cqe_next = (elm); \
(listelm)->field.cqe_prev = (elm); \
_NOTE(CONSTCOND) \
} while (0)
#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \
(elm)->field.cqe_next = (head)->cqh_first; \
(elm)->field.cqe_prev = (void *)(head); \
if ((head)->cqh_last == (void *)(head)) \
(head)->cqh_last = (elm); \
else \
(head)->cqh_first->field.cqe_prev = (elm); \
(head)->cqh_first = (elm); \
_NOTE(CONSTCOND) \
} while (0)
#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \
(elm)->field.cqe_next = (void *)(head); \
(elm)->field.cqe_prev = (head)->cqh_last; \
if ((head)->cqh_first == (void *)(head)) \
(head)->cqh_first = (elm); \
else \
(head)->cqh_last->field.cqe_next = (elm); \
(head)->cqh_last = (elm); \
_NOTE(CONSTCOND) \
} while (0)
#define CIRCLEQ_REMOVE(head, elm, field) do { \
if ((elm)->field.cqe_next == (void *)(head)) \
(head)->cqh_last = (elm)->field.cqe_prev; \
else \
(elm)->field.cqe_next->field.cqe_prev = \
(elm)->field.cqe_prev; \
if ((elm)->field.cqe_prev == (void *)(head)) \
(head)->cqh_first = (elm)->field.cqe_next; \
else \
(elm)->field.cqe_prev->field.cqe_next = \
(elm)->field.cqe_next; \
_NOTE(CONSTCOND) \
} while (0)
#define CIRCLEQ_FOREACH(var, head, field) \
for ((var) = ((head)->cqh_first); \
(var) != (void *)(head); \
(var) = ((var)->field.cqe_next))
#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \
for ((var) = ((head)->cqh_last); \
(var) != (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))
#ifdef __cplusplus
}
#endif
#endif /* !_SYS_QUEUE_H */