Archipelago » qemu

/*

 * 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.

 * 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.

 *

 * 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        8.3 (Berkeley) 12/13/93

 */

#ifndef        _SYS_QUEUE_H

#define        _SYS_QUEUE_H 1

/*

 * This file defines three types of data structures: lists, tail queues,

 * and circular queues.

 *

 * 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.

 *

 * 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.

 *

 * 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_ENTRY(type)                                                \

struct {                                                                \

        struct type *le_next;        /* next element */                        \

        struct type **le_prev;        /* address of previous next element */        \

}

/*

 * List functions.

 */

#define        LIST_INIT(head) {                                                \

        (head)->lh_first = NULL;                                        \

}

#define LIST_INSERT_AFTER(listelm, elm, 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;                \

}

#define 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;                        \

}

#define LIST_REMOVE(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;                        \

}

/*

 * Tail queue definitions.

 */

#define TAILQ_HEAD(name, type)                                                \

struct name {                                                                \

        struct type *tqh_first;        /* first element */                        \

        struct type **tqh_last;        /* addr of last next element */                \

}

#define TAILQ_ENTRY(type)                                                \

struct {                                                                \

        struct type *tqe_next;        /* next element */                        \

        struct type **tqe_prev;        /* address of previous next element */        \

}

/*

 * Tail queue functions.

 */

#define        TAILQ_INIT(head) {                                                \

        (head)->tqh_first = NULL;                                        \

        (head)->tqh_last = &(head)->tqh_first;                                \

}

#define TAILQ_INSERT_HEAD(head, elm, field) {                                \

        if (((elm)->field.tqe_next = (head)->tqh_first) != NULL)        \

                (elm)->field.tqe_next->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_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;                        \

}

#define TAILQ_INSERT_AFTER(head, listelm, elm, 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;                \

}

#define TAILQ_REMOVE(head, 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;                        \

}

/*

 * Circular queue definitions.

 */

#define CIRCLEQ_HEAD(name, type)                                        \

struct name {                                                                \

        struct type *cqh_first;                /* first element */                \

        struct type *cqh_last;                /* last element */                \

}

#define CIRCLEQ_ENTRY(type)                                                \

struct {                                                                \

        struct type *cqe_next;                /* next element */                \

        struct type *cqe_prev;                /* previous element */                \

}

/*

 * Circular queue functions.

 */

#define        CIRCLEQ_INIT(head) {                                                \

        (head)->cqh_first = (void *)(head);                                \

        (head)->cqh_last = (void *)(head);                                \

}

#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) {                \

        (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);                                \

}

#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) {                \

        (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);                                \

}

#define CIRCLEQ_INSERT_HEAD(head, elm, field) {                                \

        (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);                                        \

}

#define CIRCLEQ_INSERT_TAIL(head, elm, field) {                                \

        (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);                                        \

}

#define        CIRCLEQ_REMOVE(head, elm, field) {                                \

        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;                                \

}

#endif        /* sys/queue.h */