/**************************************************************************** * include/sys/queue.h * $OpenBSD: queue.h,v 1.46 2020/12/30 13:33:12 millert Exp $ * $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ * * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 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. 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. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)queue.h 8.5 (Berkeley) 8/20/94 ****************************************************************************/ #ifndef __INCLUDE_SYS_QUEUE_H #define __INCLUDE_SYS_QUEUE_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include /* This file defines five types of data structures: singly-linked lists, * lists, simple queues, tail queues and XOR simple 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 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 to 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 before or 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 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. * * An XOR simple queue is used in the same way as a regular simple queue. * The difference is that the head structure also includes a "cookie" that * is XOR'd with the queue pointer (first, last or next) to generate the * real pointer value. * * For details on the use of these macros, see the queue(3) manual page. */ /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #if defined(CONFIG_DEBUG_SYS_QUEUE) # define _Q_INVALID ((FAR void *)(uintptr_t)-1) # define _Q_INVALIDATE(a) ((a) = _Q_INVALID) #else # define _Q_INVALIDATE(a) #endif /* Singly-linked List definitions. */ #define SLIST_HEAD(name, type) \ struct name \ { \ FAR struct type *slh_first; /* first element */ \ } #define SLIST_HEAD_INITIALIZER(head) \ { \ NULL \ } #define SLIST_ENTRY(type) \ struct \ { \ FAR struct type *sle_next; /* next element */ \ } /* Singly-linked List access methods. */ #define SLIST_FIRST(head) ((head)->slh_first) #define SLIST_END(head) NULL #define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) #define SLIST_NEXT(elm, field) ((elm)->field.sle_next) #define SLIST_FOREACH(var, head, field) \ for ((var) = SLIST_FIRST(head); \ (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)) /* Singly-linked List functions. */ #define SLIST_INIT(head) \ do \ { \ SLIST_FIRST(head) = SLIST_END(head); \ } \ while(0) #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_INSERT_HEAD(head, elm, field) \ do \ { \ (elm)->field.sle_next = (head)->slh_first; \ (head)->slh_first = (elm); \ } \ while (0) #define SLIST_REMOVE_AFTER(elm, field) \ do \ { \ (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \ } \ while (0) #define SLIST_REMOVE_HEAD(head, field) \ do \ { \ (head)->slh_first = (head)->slh_first->field.sle_next; \ } \ while (0) #define SLIST_REMOVE(head, elm, type, field) \ do \ { \ if ((head)->slh_first == (elm)) \ { \ SLIST_REMOVE_HEAD((head), field); \ } \ else \ { \ FAR 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; \ } \ \ _Q_INVALIDATE((elm)->field.sle_next); \ } \ while (0) /* List definitions. */ #define LIST_HEAD(name, type) \ struct name \ { \ FAR struct type *lh_first; /* first element */ \ } #define LIST_HEAD_INITIALIZER(head) \ { \ NULL \ } #define LIST_ENTRY(type) \ struct \ { \ FAR struct type *le_next; /* next element */ \ FAR struct type **le_prev; /* address of previous next element */ \ } /* List access methods. */ #define LIST_FIRST(head) ((head)->lh_first) #define LIST_END(head) NULL #define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) #define LIST_NEXT(elm, field) ((elm)->field.le_next) #define LIST_FOREACH(var, head, field) \ for ((var) = LIST_FIRST(head); \ (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. */ #define LIST_INIT(head) \ do \ { \ LIST_FIRST(head) = LIST_END(head); \ } \ 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; \ } \ while (0) #define LIST_INSERT_BEFORE(listelm, elm, field) \ do \ { \ (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 (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; \ } \ while (0) #define LIST_REMOVE(elm, field) \ do \ { \ 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; \ _Q_INVALIDATE((elm)->field.le_prev); \ _Q_INVALIDATE((elm)->field.le_next); \ } \ while (0) #define LIST_REPLACE(elm, elm2, field) \ do \ { \ if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ { \ (elm2)->field.le_next->field.le_prev = \ &(elm2)->field.le_next; \ } \ \ (elm2)->field.le_prev = (elm)->field.le_prev; \ *(elm2)->field.le_prev = (elm2); \ _Q_INVALIDATE((elm)->field.le_prev); \ _Q_INVALIDATE((elm)->field.le_next); \ } \ while (0) /* Simple queue definitions. */ #define SIMPLEQ_HEAD(name, type) \ struct name \ { \ FAR struct type *sqh_first; /* first element */ \ FAR struct type **sqh_last; /* addr of last next element */ \ } #define SIMPLEQ_HEAD_INITIALIZER(head) \ { \ NULL, \ &(head).sqh_first \ } #define SIMPLEQ_ENTRY(type) \ struct \ { \ FAR struct type *sqe_next; /* next element */ \ } /* Simple queue access methods. */ #define SIMPLEQ_FIRST(head) ((head)->sqh_first) #define SIMPLEQ_END(head) NULL #define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) #define SIMPLEQ_FOREACH(var, head, field) \ for ((var) = SIMPLEQ_FIRST(head); \ (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. */ #define SIMPLEQ_INIT(head) \ do \ { \ (head)->sqh_first = NULL; \ (head)->sqh_last = &(head)->sqh_first; \ } \ 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); \ } \ 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; \ } \ 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); \ } \ 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; \ } \ } \ while (0) #define SIMPLEQ_REMOVE_AFTER(head, elm, field) \ do \ { \ if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \ == NULL) \ { \ (head)->sqh_last = &(elm)->field.sqe_next; \ } \ } \ while (0) #define SIMPLEQ_CONCAT(head1, head2) \ do \ { \ if (!SIMPLEQ_EMPTY((head2))) \ { \ *(head1)->sqh_last = (head2)->sqh_first; \ (head1)->sqh_last = (head2)->sqh_last; \ SIMPLEQ_INIT((head2)); \ } \ } \ while (0) /* XOR Simple queue definitions. */ #define XSIMPLEQ_HEAD(name, type) \ struct name \ { \ FAR struct type *sqx_first; /* first element */ \ FAR struct type **sqx_last; /* addr of last next element */ \ unsigned long sqx_cookie; \ } #define XSIMPLEQ_ENTRY(type) \ struct \ { \ FAR struct type *sqx_next; /* next element */ \ } /* XOR Simple queue access methods. */ #define XSIMPLEQ_XOR(head, ptr) ((__typeof(ptr))((head)->sqx_cookie ^ \ (unsigned long)(ptr))) #define XSIMPLEQ_FIRST(head) XSIMPLEQ_XOR(head, ((head)->sqx_first)) #define XSIMPLEQ_END(head) NULL #define XSIMPLEQ_EMPTY(head) (XSIMPLEQ_FIRST(head) == XSIMPLEQ_END(head)) #define XSIMPLEQ_NEXT(head, elm, field) XSIMPLEQ_XOR(head, ((elm)->field.sqx_next)) #define XSIMPLEQ_FOREACH(var, head, field) \ for ((var) = XSIMPLEQ_FIRST(head); \ (var) != XSIMPLEQ_END(head); \ (var) = XSIMPLEQ_NEXT(head, var, field)) #define XSIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \ for ((var) = XSIMPLEQ_FIRST(head); \ (var) && ((tvar) = XSIMPLEQ_NEXT(head, var, field), 1); \ (var) = (tvar)) /* XOR Simple queue functions. */ #define XSIMPLEQ_INIT(head) \ do \ { \ arc4random_buf(&(head)->sqx_cookie, sizeof((head)->sqx_cookie)); \ (head)->sqx_first = XSIMPLEQ_XOR(head, NULL); \ (head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \ } \ while (0) #define XSIMPLEQ_INSERT_HEAD(head, elm, field) \ do \ { \ if (((elm)->field.sqx_next = (head)->sqx_first) == \ XSIMPLEQ_XOR(head, NULL)) \ { \ (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ } \ \ (head)->sqx_first = XSIMPLEQ_XOR(head, (elm)); \ } \ while (0) #define XSIMPLEQ_INSERT_TAIL(head, elm, field) \ do \ { \ (elm)->field.sqx_next = XSIMPLEQ_XOR(head, NULL); \ *(XSIMPLEQ_XOR(head, (head)->sqx_last)) = XSIMPLEQ_XOR(head, (elm)); \ (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ } \ while (0) #define XSIMPLEQ_INSERT_AFTER(head, listelm, elm, field) \ do \ { \ if (((elm)->field.sqx_next = (listelm)->field.sqx_next) == \ XSIMPLEQ_XOR(head, NULL)) \ { \ (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ } \ \ (listelm)->field.sqx_next = XSIMPLEQ_XOR(head, (elm)); \ } \ while (0) #define XSIMPLEQ_REMOVE_HEAD(head, field) \ do \ { \ if (((head)->sqx_first = XSIMPLEQ_XOR(head, \ (head)->sqx_first)->field.sqx_next) == XSIMPLEQ_XOR(head, NULL)) \ { \ (head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \ } \ } \ while (0) #define XSIMPLEQ_REMOVE_AFTER(head, elm, field) \ do \ { \ if (((elm)->field.sqx_next = XSIMPLEQ_XOR(head, \ (elm)->field.sqx_next)->field.sqx_next) \ == XSIMPLEQ_XOR(head, NULL)) \ { \ (head)->sqx_last = \ XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \ } \ } \ while (0) \ /* Tail queue definitions. */ #define TAILQ_HEAD(name, type) \ struct name \ { \ FAR struct type *tqh_first; /* first element */ \ FAR struct type **tqh_last; /* addr of last next element */ \ } #define TAILQ_HEAD_INITIALIZER(head) \ { \ NULL, \ &(head).tqh_first \ } #define TAILQ_ENTRY(type) \ struct \ { \ FAR struct type *tqe_next; /* next element */ \ FAR struct type **tqe_prev; /* address of previous next element */ \ } /* Tail queue access methods. */ #define TAILQ_FIRST(head) ((head)->tqh_first) #define TAILQ_END(head) NULL #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) #define TAILQ_LAST(head, headname) \ (*(((FAR struct headname *)((head)->tqh_last))->tqh_last)) /* XXX */ #define TAILQ_PREV(elm, headname, field) \ (*(((FAR struct headname *)((elm)->field.tqe_prev))->tqh_last)) #define TAILQ_EMPTY(head) \ (TAILQ_FIRST(head) == TAILQ_END(head)) #define TAILQ_FOREACH(var, head, field) \ for ((var) = TAILQ_FIRST(head); \ (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. */ #define TAILQ_INIT(head) \ do \ { \ (head)->tqh_first = NULL; \ (head)->tqh_last = &(head)->tqh_first; \ } \ 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; \ } \ 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; \ } \ 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; \ } \ else \ { \ (head)->tqh_last = &(elm)->field.tqe_next; \ } \ \ (listelm)->field.tqe_next = (elm); \ (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ } \ 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; \ } \ while (0) #define TAILQ_REMOVE(head, elm, field) \ do \ { \ 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; \ _Q_INVALIDATE((elm)->field.tqe_prev); \ _Q_INVALIDATE((elm)->field.tqe_next); \ } \ while (0) #define TAILQ_REPLACE(head, elm, elm2, field) \ do \ { \ if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ { \ (elm2)->field.tqe_next->field.tqe_prev = \ &(elm2)->field.tqe_next; \ } \ else \ { \ (head)->tqh_last = &(elm2)->field.tqe_next; \ } \ \ (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ *(elm2)->field.tqe_prev = (elm2); \ _Q_INVALIDATE((elm)->field.tqe_prev); \ _Q_INVALIDATE((elm)->field.tqe_next); \ } \ while (0) #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)); \ } \ } \ while (0) /* Singly-linked Tail queue declarations. */ #define STAILQ_HEAD(name, type) \ struct name \ { \ FAR struct type *stqh_first; /* first element */ \ FAR struct type **stqh_last; /* addr of last next element */ \ } #define STAILQ_HEAD_INITIALIZER(head) \ { \ NULL, \ &(head).stqh_first \ } #define STAILQ_ENTRY(type) \ struct \ { \ FAR struct type *stqe_next; /* next element */ \ } /* Singly-linked Tail queue access methods. */ #define STAILQ_FIRST(head) ((head)->stqh_first) #define STAILQ_END(head) NULL #define STAILQ_EMPTY(head) (STAILQ_FIRST(head) == STAILQ_END(head)) #define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) #define STAILQ_FOREACH(var, head, field) \ for ((var) = STAILQ_FIRST(head); \ (var) != STAILQ_END(head); \ (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)) /* Singly-linked Tail queue functions. */ #define STAILQ_INIT(head) \ do \ { \ STAILQ_FIRST(head) = NULL; \ (head)->stqh_last = &STAILQ_FIRST(head); \ } \ while (0) #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 \ { \ STAILQ_NEXT((elm), field) = NULL; \ *(head)->stqh_last = (elm); \ (head)->stqh_last = &STAILQ_NEXT((elm), field); \ } \ while (0) #define STAILQ_INSERT_AFTER(head, listelm, elm, field) \ do \ { \ if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((elm), field)) == NULL) \ (head)->stqh_last = &STAILQ_NEXT((elm), field); \ { \ STAILQ_NEXT((elm), field) = (elm); \ } \ } \ while (0) #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_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_REMOVE(head, elm, type, field) \ do \ { \ if (STAILQ_FIRST((head)) == (elm)) \ { \ STAILQ_REMOVE_HEAD((head), field); \ } \ else \ { \ FAR struct type *curelm = (head)->stqh_first; \ while (STAILQ_NEXT(curelm, field) != (elm)) \ curelm = STAILQ_NEXT(curelm, field); \ STAILQ_REMOVE_AFTER(head, curelm, field); \ } \ } \ while (0) #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_LAST(head, type, field) \ (STAILQ_EMPTY((head)) ? NULL : \ ((FAR struct type *)(FAR void *) \ ((FAR char *)((head)->stqh_last) - offsetof(struct type, field)))) #endif /* __INCLUDE_SYS_QUEUE_H */