| /* $NetBSD: queue.h,v 1.52 2009/04/20 09:56:08 mschuett Exp $ */ |
| |
| /* |
| * QEMU version: Copy from netbsd, removed debug code, removed some of |
| * the implementations. Left in singly-linked lists, lists, simple |
| * queues, and tail queues. |
| */ |
| |
| /* |
| * 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 QEMU_SYS_QUEUE_H_ |
| #define QEMU_SYS_QUEUE_H_ |
| |
| /* |
| * This file defines four types of data structures: singly-linked lists, |
| * lists, simple queues, and tail 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 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 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. |
| * |
| * For details on the use of these macros, see the queue(3) manual page. |
| */ |
| |
| #include "qemu/atomic.h" /* for smp_wmb() */ |
| |
| /* |
| * List definitions. |
| */ |
| #define QLIST_HEAD(name, type) \ |
| struct name { \ |
| struct type *lh_first; /* first element */ \ |
| } |
| |
| #define QLIST_HEAD_INITIALIZER(head) \ |
| { NULL } |
| |
| #define QLIST_ENTRY(type) \ |
| struct { \ |
| struct type *le_next; /* next element */ \ |
| struct type **le_prev; /* address of previous next element */ \ |
| } |
| |
| /* |
| * List functions. |
| */ |
| #define QLIST_INIT(head) do { \ |
| (head)->lh_first = NULL; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QLIST_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 (/*CONSTCOND*/0) |
| |
| #define QLIST_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 (/*CONSTCOND*/0) |
| |
| #define QLIST_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 (/*CONSTCOND*/0) |
| |
| #define QLIST_INSERT_HEAD_RCU(head, elm, field) do { \ |
| (elm)->field.le_prev = &(head)->lh_first; \ |
| (elm)->field.le_next = (head)->lh_first; \ |
| smp_wmb(); /* fill elm before linking it */ \ |
| if ((head)->lh_first != NULL) { \ |
| (head)->lh_first->field.le_prev = &(elm)->field.le_next; \ |
| } \ |
| (head)->lh_first = (elm); \ |
| smp_wmb(); \ |
| } while (/* CONSTCOND*/0) |
| |
| #define QLIST_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; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QLIST_FOREACH(var, head, field) \ |
| for ((var) = ((head)->lh_first); \ |
| (var); \ |
| (var) = ((var)->field.le_next)) |
| |
| #define QLIST_FOREACH_SAFE(var, head, field, next_var) \ |
| for ((var) = ((head)->lh_first); \ |
| (var) && ((next_var) = ((var)->field.le_next), 1); \ |
| (var) = (next_var)) |
| |
| /* |
| * List access methods. |
| */ |
| #define QLIST_EMPTY(head) ((head)->lh_first == NULL) |
| #define QLIST_FIRST(head) ((head)->lh_first) |
| #define QLIST_NEXT(elm, field) ((elm)->field.le_next) |
| |
| |
| /* |
| * Singly-linked List definitions. |
| */ |
| #define QSLIST_HEAD(name, type) \ |
| struct name { \ |
| struct type *slh_first; /* first element */ \ |
| } |
| |
| #define QSLIST_HEAD_INITIALIZER(head) \ |
| { NULL } |
| |
| #define QSLIST_ENTRY(type) \ |
| struct { \ |
| struct type *sle_next; /* next element */ \ |
| } |
| |
| /* |
| * Singly-linked List functions. |
| */ |
| #define QSLIST_INIT(head) do { \ |
| (head)->slh_first = NULL; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSLIST_INSERT_AFTER(slistelm, elm, field) do { \ |
| (elm)->field.sle_next = (slistelm)->field.sle_next; \ |
| (slistelm)->field.sle_next = (elm); \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSLIST_INSERT_HEAD(head, elm, field) do { \ |
| (elm)->field.sle_next = (head)->slh_first; \ |
| (head)->slh_first = (elm); \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSLIST_REMOVE_HEAD(head, field) do { \ |
| (head)->slh_first = (head)->slh_first->field.sle_next; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSLIST_REMOVE_AFTER(slistelm, field) do { \ |
| (slistelm)->field.sle_next = \ |
| QSLIST_NEXT(QSLIST_NEXT((slistelm), field), field); \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSLIST_FOREACH(var, head, field) \ |
| for((var) = (head)->slh_first; (var); (var) = (var)->field.sle_next) |
| |
| #define QSLIST_FOREACH_SAFE(var, head, field, tvar) \ |
| for ((var) = QSLIST_FIRST((head)); \ |
| (var) && ((tvar) = QSLIST_NEXT((var), field), 1); \ |
| (var) = (tvar)) |
| |
| /* |
| * Singly-linked List access methods. |
| */ |
| #define QSLIST_EMPTY(head) ((head)->slh_first == NULL) |
| #define QSLIST_FIRST(head) ((head)->slh_first) |
| #define QSLIST_NEXT(elm, field) ((elm)->field.sle_next) |
| |
| |
| /* |
| * Simple queue definitions. |
| */ |
| #define QSIMPLEQ_HEAD(name, type) \ |
| struct name { \ |
| struct type *sqh_first; /* first element */ \ |
| struct type **sqh_last; /* addr of last next element */ \ |
| } |
| |
| #define QSIMPLEQ_HEAD_INITIALIZER(head) \ |
| { NULL, &(head).sqh_first } |
| |
| #define QSIMPLEQ_ENTRY(type) \ |
| struct { \ |
| struct type *sqe_next; /* next element */ \ |
| } |
| |
| /* |
| * Simple queue functions. |
| */ |
| #define QSIMPLEQ_INIT(head) do { \ |
| (head)->sqh_first = NULL; \ |
| (head)->sqh_last = &(head)->sqh_first; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSIMPLEQ_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 QSIMPLEQ_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 QSIMPLEQ_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 QSIMPLEQ_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 QSIMPLEQ_REMOVE(head, elm, type, field) do { \ |
| if ((head)->sqh_first == (elm)) { \ |
| QSIMPLEQ_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 QSIMPLEQ_FOREACH(var, head, field) \ |
| for ((var) = ((head)->sqh_first); \ |
| (var); \ |
| (var) = ((var)->field.sqe_next)) |
| |
| #define QSIMPLEQ_FOREACH_SAFE(var, head, field, next) \ |
| for ((var) = ((head)->sqh_first); \ |
| (var) && ((next = ((var)->field.sqe_next)), 1); \ |
| (var) = (next)) |
| |
| #define QSIMPLEQ_CONCAT(head1, head2) do { \ |
| if (!QSIMPLEQ_EMPTY((head2))) { \ |
| *(head1)->sqh_last = (head2)->sqh_first; \ |
| (head1)->sqh_last = (head2)->sqh_last; \ |
| QSIMPLEQ_INIT((head2)); \ |
| } \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QSIMPLEQ_LAST(head, type, field) \ |
| (QSIMPLEQ_EMPTY((head)) ? \ |
| NULL : \ |
| ((struct type *)(void *) \ |
| ((char *)((head)->sqh_last) - offsetof(struct type, field)))) |
| |
| /* |
| * Simple queue access methods. |
| */ |
| #define QSIMPLEQ_EMPTY(head) ((head)->sqh_first == NULL) |
| #define QSIMPLEQ_FIRST(head) ((head)->sqh_first) |
| #define QSIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) |
| |
| |
| /* |
| * Tail queue definitions. |
| */ |
| #define Q_TAILQ_HEAD(name, type, qual) \ |
| struct name { \ |
| qual type *tqh_first; /* first element */ \ |
| qual type *qual *tqh_last; /* addr of last next element */ \ |
| } |
| #define QTAILQ_HEAD(name, type) Q_TAILQ_HEAD(name, struct type,) |
| |
| #define QTAILQ_HEAD_INITIALIZER(head) \ |
| { NULL, &(head).tqh_first } |
| |
| #define Q_TAILQ_ENTRY(type, qual) \ |
| struct { \ |
| qual type *tqe_next; /* next element */ \ |
| qual type *qual *tqe_prev; /* address of previous next element */\ |
| } |
| #define QTAILQ_ENTRY(type) Q_TAILQ_ENTRY(struct type,) |
| |
| /* |
| * Tail queue functions. |
| */ |
| #define QTAILQ_INIT(head) do { \ |
| (head)->tqh_first = NULL; \ |
| (head)->tqh_last = &(head)->tqh_first; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QTAILQ_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 (/*CONSTCOND*/0) |
| |
| #define QTAILQ_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 (/*CONSTCOND*/0) |
| |
| #define QTAILQ_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 (/*CONSTCOND*/0) |
| |
| #define QTAILQ_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 (/*CONSTCOND*/0) |
| |
| #define QTAILQ_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; \ |
| } while (/*CONSTCOND*/0) |
| |
| #define QTAILQ_FOREACH(var, head, field) \ |
| for ((var) = ((head)->tqh_first); \ |
| (var); \ |
| (var) = ((var)->field.tqe_next)) |
| |
| #define QTAILQ_FOREACH_SAFE(var, head, field, next_var) \ |
| for ((var) = ((head)->tqh_first); \ |
| (var) && ((next_var) = ((var)->field.tqe_next), 1); \ |
| (var) = (next_var)) |
| |
| #define QTAILQ_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 QTAILQ_EMPTY(head) ((head)->tqh_first == NULL) |
| #define QTAILQ_FIRST(head) ((head)->tqh_first) |
| #define QTAILQ_NEXT(elm, field) ((elm)->field.tqe_next) |
| |
| #define QTAILQ_LAST(head, headname) \ |
| (*(((struct headname *)((head)->tqh_last))->tqh_last)) |
| #define QTAILQ_PREV(elm, headname, field) \ |
| (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) |
| |
| #endif /* !QEMU_SYS_QUEUE_H_ */ |
