1 6b191ed5 2021-02-23 op /* $OpenBSD: queue.h,v 1.45 2018/07/12 14:22:54 sashan Exp $ */
2 6b191ed5 2021-02-23 op /* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */
5 6b191ed5 2021-02-23 op * Copyright (c) 1991, 1993
6 6b191ed5 2021-02-23 op * The Regents of the University of California. All rights reserved.
8 6b191ed5 2021-02-23 op * Redistribution and use in source and binary forms, with or without
9 6b191ed5 2021-02-23 op * modification, are permitted provided that the following conditions
11 6b191ed5 2021-02-23 op * 1. Redistributions of source code must retain the above copyright
12 6b191ed5 2021-02-23 op * notice, this list of conditions and the following disclaimer.
13 6b191ed5 2021-02-23 op * 2. Redistributions in binary form must reproduce the above copyright
14 6b191ed5 2021-02-23 op * notice, this list of conditions and the following disclaimer in the
15 6b191ed5 2021-02-23 op * documentation and/or other materials provided with the distribution.
16 6b191ed5 2021-02-23 op * 3. Neither the name of the University nor the names of its contributors
17 6b191ed5 2021-02-23 op * may be used to endorse or promote products derived from this software
18 6b191ed5 2021-02-23 op * without specific prior written permission.
20 6b191ed5 2021-02-23 op * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 6b191ed5 2021-02-23 op * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 6b191ed5 2021-02-23 op * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 6b191ed5 2021-02-23 op * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 6b191ed5 2021-02-23 op * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 6b191ed5 2021-02-23 op * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 6b191ed5 2021-02-23 op * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 6b191ed5 2021-02-23 op * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 6b191ed5 2021-02-23 op * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 6b191ed5 2021-02-23 op * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 6b191ed5 2021-02-23 op * SUCH DAMAGE.
32 6b191ed5 2021-02-23 op * @(#)queue.h 8.5 (Berkeley) 8/20/94
35 6b191ed5 2021-02-23 op #ifndef _SYS_QUEUE_H_
36 6b191ed5 2021-02-23 op #define _SYS_QUEUE_H_
39 6b191ed5 2021-02-23 op * This file defines five types of data structures: singly-linked lists,
40 6b191ed5 2021-02-23 op * lists, simple queues, tail queues and XOR simple queues.
43 6b191ed5 2021-02-23 op * A singly-linked list is headed by a single forward pointer. The elements
44 6b191ed5 2021-02-23 op * are singly linked for minimum space and pointer manipulation overhead at
45 6b191ed5 2021-02-23 op * the expense of O(n) removal for arbitrary elements. New elements can be
46 6b191ed5 2021-02-23 op * added to the list after an existing element or at the head of the list.
47 6b191ed5 2021-02-23 op * Elements being removed from the head of the list should use the explicit
48 6b191ed5 2021-02-23 op * macro for this purpose for optimum efficiency. A singly-linked list may
49 6b191ed5 2021-02-23 op * only be traversed in the forward direction. Singly-linked lists are ideal
50 6b191ed5 2021-02-23 op * for applications with large datasets and few or no removals or for
51 6b191ed5 2021-02-23 op * implementing a LIFO queue.
53 6b191ed5 2021-02-23 op * A list is headed by a single forward pointer (or an array of forward
54 6b191ed5 2021-02-23 op * pointers for a hash table header). The elements are doubly linked
55 6b191ed5 2021-02-23 op * so that an arbitrary element can be removed without a need to
56 6b191ed5 2021-02-23 op * traverse the list. New elements can be added to the list before
57 6b191ed5 2021-02-23 op * or after an existing element or at the head of the list. A list
58 6b191ed5 2021-02-23 op * may only be traversed in the forward direction.
60 6b191ed5 2021-02-23 op * A simple queue is headed by a pair of pointers, one to the head of the
61 6b191ed5 2021-02-23 op * list and the other to the tail of the list. The elements are singly
62 6b191ed5 2021-02-23 op * linked to save space, so elements can only be removed from the
63 6b191ed5 2021-02-23 op * head of the list. New elements can be added to the list before or after
64 6b191ed5 2021-02-23 op * an existing element, at the head of the list, or at the end of the
65 6b191ed5 2021-02-23 op * list. A simple queue may only be traversed in the forward direction.
67 6b191ed5 2021-02-23 op * A tail queue is headed by a pair of pointers, one to the head of the
68 6b191ed5 2021-02-23 op * list and the other to the tail of the list. The elements are doubly
69 6b191ed5 2021-02-23 op * linked so that an arbitrary element can be removed without a need to
70 6b191ed5 2021-02-23 op * traverse the list. New elements can be added to the list before or
71 6b191ed5 2021-02-23 op * after an existing element, at the head of the list, or at the end of
72 6b191ed5 2021-02-23 op * the list. A tail queue may be traversed in either direction.
74 6b191ed5 2021-02-23 op * An XOR simple queue is used in the same way as a regular simple queue.
75 6b191ed5 2021-02-23 op * The difference is that the head structure also includes a "cookie" that
76 6b191ed5 2021-02-23 op * is XOR'd with the queue pointer (first, last or next) to generate the
77 6b191ed5 2021-02-23 op * real pointer value.
79 6b191ed5 2021-02-23 op * For details on the use of these macros, see the queue(3) manual page.
82 6b191ed5 2021-02-23 op #if defined(QUEUE_MACRO_DEBUG) || (defined(_KERNEL) && defined(DIAGNOSTIC))
83 6b191ed5 2021-02-23 op #define _Q_INVALID ((void *)-1)
84 6b191ed5 2021-02-23 op #define _Q_INVALIDATE(a) (a) = _Q_INVALID
86 6b191ed5 2021-02-23 op #define _Q_INVALIDATE(a)
90 6b191ed5 2021-02-23 op * Singly-linked List definitions.
92 6b191ed5 2021-02-23 op #define SLIST_HEAD(name, type) \
93 6b191ed5 2021-02-23 op struct name { \
94 6b191ed5 2021-02-23 op struct type *slh_first; /* first element */ \
97 6b191ed5 2021-02-23 op #define SLIST_HEAD_INITIALIZER(head) \
100 6b191ed5 2021-02-23 op #define SLIST_ENTRY(type) \
102 6b191ed5 2021-02-23 op struct type *sle_next; /* next element */ \
106 6b191ed5 2021-02-23 op * Singly-linked List access methods.
108 6b191ed5 2021-02-23 op #define SLIST_FIRST(head) ((head)->slh_first)
109 6b191ed5 2021-02-23 op #define SLIST_END(head) NULL
110 6b191ed5 2021-02-23 op #define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head))
111 6b191ed5 2021-02-23 op #define SLIST_NEXT(elm, field) ((elm)->field.sle_next)
113 6b191ed5 2021-02-23 op #define SLIST_FOREACH(var, head, field) \
114 6b191ed5 2021-02-23 op for((var) = SLIST_FIRST(head); \
115 6b191ed5 2021-02-23 op (var) != SLIST_END(head); \
116 6b191ed5 2021-02-23 op (var) = SLIST_NEXT(var, field))
118 6b191ed5 2021-02-23 op #define SLIST_FOREACH_SAFE(var, head, field, tvar) \
119 6b191ed5 2021-02-23 op for ((var) = SLIST_FIRST(head); \
120 6b191ed5 2021-02-23 op (var) && ((tvar) = SLIST_NEXT(var, field), 1); \
121 6b191ed5 2021-02-23 op (var) = (tvar))
124 6b191ed5 2021-02-23 op * Singly-linked List functions.
126 6b191ed5 2021-02-23 op #define SLIST_INIT(head) { \
127 6b191ed5 2021-02-23 op SLIST_FIRST(head) = SLIST_END(head); \
130 6b191ed5 2021-02-23 op #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
131 6b191ed5 2021-02-23 op (elm)->field.sle_next = (slistelm)->field.sle_next; \
132 6b191ed5 2021-02-23 op (slistelm)->field.sle_next = (elm); \
135 6b191ed5 2021-02-23 op #define SLIST_INSERT_HEAD(head, elm, field) do { \
136 6b191ed5 2021-02-23 op (elm)->field.sle_next = (head)->slh_first; \
137 6b191ed5 2021-02-23 op (head)->slh_first = (elm); \
140 6b191ed5 2021-02-23 op #define SLIST_REMOVE_AFTER(elm, field) do { \
141 6b191ed5 2021-02-23 op (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \
144 6b191ed5 2021-02-23 op #define SLIST_REMOVE_HEAD(head, field) do { \
145 6b191ed5 2021-02-23 op (head)->slh_first = (head)->slh_first->field.sle_next; \
148 6b191ed5 2021-02-23 op #define SLIST_REMOVE(head, elm, type, field) do { \
149 6b191ed5 2021-02-23 op if ((head)->slh_first == (elm)) { \
150 6b191ed5 2021-02-23 op SLIST_REMOVE_HEAD((head), field); \
152 6b191ed5 2021-02-23 op struct type *curelm = (head)->slh_first; \
154 6b191ed5 2021-02-23 op while (curelm->field.sle_next != (elm)) \
155 6b191ed5 2021-02-23 op curelm = curelm->field.sle_next; \
156 6b191ed5 2021-02-23 op curelm->field.sle_next = \
157 6b191ed5 2021-02-23 op curelm->field.sle_next->field.sle_next; \
159 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.sle_next); \
163 6b191ed5 2021-02-23 op * List definitions.
165 6b191ed5 2021-02-23 op #define LIST_HEAD(name, type) \
166 6b191ed5 2021-02-23 op struct name { \
167 6b191ed5 2021-02-23 op struct type *lh_first; /* first element */ \
170 6b191ed5 2021-02-23 op #define LIST_HEAD_INITIALIZER(head) \
173 6b191ed5 2021-02-23 op #define LIST_ENTRY(type) \
175 6b191ed5 2021-02-23 op struct type *le_next; /* next element */ \
176 6b191ed5 2021-02-23 op struct type **le_prev; /* address of previous next element */ \
180 6b191ed5 2021-02-23 op * List access methods.
182 6b191ed5 2021-02-23 op #define LIST_FIRST(head) ((head)->lh_first)
183 6b191ed5 2021-02-23 op #define LIST_END(head) NULL
184 6b191ed5 2021-02-23 op #define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head))
185 6b191ed5 2021-02-23 op #define LIST_NEXT(elm, field) ((elm)->field.le_next)
187 6b191ed5 2021-02-23 op #define LIST_FOREACH(var, head, field) \
188 6b191ed5 2021-02-23 op for((var) = LIST_FIRST(head); \
189 6b191ed5 2021-02-23 op (var)!= LIST_END(head); \
190 6b191ed5 2021-02-23 op (var) = LIST_NEXT(var, field))
192 6b191ed5 2021-02-23 op #define LIST_FOREACH_SAFE(var, head, field, tvar) \
193 6b191ed5 2021-02-23 op for ((var) = LIST_FIRST(head); \
194 6b191ed5 2021-02-23 op (var) && ((tvar) = LIST_NEXT(var, field), 1); \
195 6b191ed5 2021-02-23 op (var) = (tvar))
198 6b191ed5 2021-02-23 op * List functions.
200 6b191ed5 2021-02-23 op #define LIST_INIT(head) do { \
201 6b191ed5 2021-02-23 op LIST_FIRST(head) = LIST_END(head); \
204 6b191ed5 2021-02-23 op #define LIST_INSERT_AFTER(listelm, elm, field) do { \
205 6b191ed5 2021-02-23 op if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \
206 6b191ed5 2021-02-23 op (listelm)->field.le_next->field.le_prev = \
207 6b191ed5 2021-02-23 op &(elm)->field.le_next; \
208 6b191ed5 2021-02-23 op (listelm)->field.le_next = (elm); \
209 6b191ed5 2021-02-23 op (elm)->field.le_prev = &(listelm)->field.le_next; \
212 6b191ed5 2021-02-23 op #define LIST_INSERT_BEFORE(listelm, elm, field) do { \
213 6b191ed5 2021-02-23 op (elm)->field.le_prev = (listelm)->field.le_prev; \
214 6b191ed5 2021-02-23 op (elm)->field.le_next = (listelm); \
215 6b191ed5 2021-02-23 op *(listelm)->field.le_prev = (elm); \
216 6b191ed5 2021-02-23 op (listelm)->field.le_prev = &(elm)->field.le_next; \
219 6b191ed5 2021-02-23 op #define LIST_INSERT_HEAD(head, elm, field) do { \
220 6b191ed5 2021-02-23 op if (((elm)->field.le_next = (head)->lh_first) != NULL) \
221 6b191ed5 2021-02-23 op (head)->lh_first->field.le_prev = &(elm)->field.le_next;\
222 6b191ed5 2021-02-23 op (head)->lh_first = (elm); \
223 6b191ed5 2021-02-23 op (elm)->field.le_prev = &(head)->lh_first; \
226 6b191ed5 2021-02-23 op #define LIST_REMOVE(elm, field) do { \
227 6b191ed5 2021-02-23 op if ((elm)->field.le_next != NULL) \
228 6b191ed5 2021-02-23 op (elm)->field.le_next->field.le_prev = \
229 6b191ed5 2021-02-23 op (elm)->field.le_prev; \
230 6b191ed5 2021-02-23 op *(elm)->field.le_prev = (elm)->field.le_next; \
231 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.le_prev); \
232 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.le_next); \
235 6b191ed5 2021-02-23 op #define LIST_REPLACE(elm, elm2, field) do { \
236 6b191ed5 2021-02-23 op if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \
237 6b191ed5 2021-02-23 op (elm2)->field.le_next->field.le_prev = \
238 6b191ed5 2021-02-23 op &(elm2)->field.le_next; \
239 6b191ed5 2021-02-23 op (elm2)->field.le_prev = (elm)->field.le_prev; \
240 6b191ed5 2021-02-23 op *(elm2)->field.le_prev = (elm2); \
241 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.le_prev); \
242 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.le_next); \
246 6b191ed5 2021-02-23 op * Simple queue definitions.
248 6b191ed5 2021-02-23 op #define SIMPLEQ_HEAD(name, type) \
249 6b191ed5 2021-02-23 op struct name { \
250 6b191ed5 2021-02-23 op struct type *sqh_first; /* first element */ \
251 6b191ed5 2021-02-23 op struct type **sqh_last; /* addr of last next element */ \
254 6b191ed5 2021-02-23 op #define SIMPLEQ_HEAD_INITIALIZER(head) \
255 6b191ed5 2021-02-23 op { NULL, &(head).sqh_first }
257 6b191ed5 2021-02-23 op #define SIMPLEQ_ENTRY(type) \
259 6b191ed5 2021-02-23 op struct type *sqe_next; /* next element */ \
263 6b191ed5 2021-02-23 op * Simple queue access methods.
265 6b191ed5 2021-02-23 op #define SIMPLEQ_FIRST(head) ((head)->sqh_first)
266 6b191ed5 2021-02-23 op #define SIMPLEQ_END(head) NULL
267 6b191ed5 2021-02-23 op #define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
268 6b191ed5 2021-02-23 op #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next)
270 6b191ed5 2021-02-23 op #define SIMPLEQ_FOREACH(var, head, field) \
271 6b191ed5 2021-02-23 op for((var) = SIMPLEQ_FIRST(head); \
272 6b191ed5 2021-02-23 op (var) != SIMPLEQ_END(head); \
273 6b191ed5 2021-02-23 op (var) = SIMPLEQ_NEXT(var, field))
275 6b191ed5 2021-02-23 op #define SIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \
276 6b191ed5 2021-02-23 op for ((var) = SIMPLEQ_FIRST(head); \
277 6b191ed5 2021-02-23 op (var) && ((tvar) = SIMPLEQ_NEXT(var, field), 1); \
278 6b191ed5 2021-02-23 op (var) = (tvar))
281 6b191ed5 2021-02-23 op * Simple queue functions.
283 6b191ed5 2021-02-23 op #define SIMPLEQ_INIT(head) do { \
284 6b191ed5 2021-02-23 op (head)->sqh_first = NULL; \
285 6b191ed5 2021-02-23 op (head)->sqh_last = &(head)->sqh_first; \
288 6b191ed5 2021-02-23 op #define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \
289 6b191ed5 2021-02-23 op if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \
290 6b191ed5 2021-02-23 op (head)->sqh_last = &(elm)->field.sqe_next; \
291 6b191ed5 2021-02-23 op (head)->sqh_first = (elm); \
294 6b191ed5 2021-02-23 op #define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \
295 6b191ed5 2021-02-23 op (elm)->field.sqe_next = NULL; \
296 6b191ed5 2021-02-23 op *(head)->sqh_last = (elm); \
297 6b191ed5 2021-02-23 op (head)->sqh_last = &(elm)->field.sqe_next; \
300 6b191ed5 2021-02-23 op #define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
301 6b191ed5 2021-02-23 op if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
302 6b191ed5 2021-02-23 op (head)->sqh_last = &(elm)->field.sqe_next; \
303 6b191ed5 2021-02-23 op (listelm)->field.sqe_next = (elm); \
306 6b191ed5 2021-02-23 op #define SIMPLEQ_REMOVE_HEAD(head, field) do { \
307 6b191ed5 2021-02-23 op if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \
308 6b191ed5 2021-02-23 op (head)->sqh_last = &(head)->sqh_first; \
311 6b191ed5 2021-02-23 op #define SIMPLEQ_REMOVE_AFTER(head, elm, field) do { \
312 6b191ed5 2021-02-23 op if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \
314 6b191ed5 2021-02-23 op (head)->sqh_last = &(elm)->field.sqe_next; \
317 6b191ed5 2021-02-23 op #define SIMPLEQ_CONCAT(head1, head2) do { \
318 6b191ed5 2021-02-23 op if (!SIMPLEQ_EMPTY((head2))) { \
319 6b191ed5 2021-02-23 op *(head1)->sqh_last = (head2)->sqh_first; \
320 6b191ed5 2021-02-23 op (head1)->sqh_last = (head2)->sqh_last; \
321 6b191ed5 2021-02-23 op SIMPLEQ_INIT((head2)); \
326 6b191ed5 2021-02-23 op * XOR Simple queue definitions.
328 6b191ed5 2021-02-23 op #define XSIMPLEQ_HEAD(name, type) \
329 6b191ed5 2021-02-23 op struct name { \
330 6b191ed5 2021-02-23 op struct type *sqx_first; /* first element */ \
331 6b191ed5 2021-02-23 op struct type **sqx_last; /* addr of last next element */ \
332 6b191ed5 2021-02-23 op unsigned long sqx_cookie; \
335 6b191ed5 2021-02-23 op #define XSIMPLEQ_ENTRY(type) \
337 6b191ed5 2021-02-23 op struct type *sqx_next; /* next element */ \
341 6b191ed5 2021-02-23 op * XOR Simple queue access methods.
343 6b191ed5 2021-02-23 op #define XSIMPLEQ_XOR(head, ptr) ((__typeof(ptr))((head)->sqx_cookie ^ \
344 6b191ed5 2021-02-23 op (unsigned long)(ptr)))
345 6b191ed5 2021-02-23 op #define XSIMPLEQ_FIRST(head) XSIMPLEQ_XOR(head, ((head)->sqx_first))
346 6b191ed5 2021-02-23 op #define XSIMPLEQ_END(head) NULL
347 6b191ed5 2021-02-23 op #define XSIMPLEQ_EMPTY(head) (XSIMPLEQ_FIRST(head) == XSIMPLEQ_END(head))
348 6b191ed5 2021-02-23 op #define XSIMPLEQ_NEXT(head, elm, field) XSIMPLEQ_XOR(head, ((elm)->field.sqx_next))
351 6b191ed5 2021-02-23 op #define XSIMPLEQ_FOREACH(var, head, field) \
352 6b191ed5 2021-02-23 op for ((var) = XSIMPLEQ_FIRST(head); \
353 6b191ed5 2021-02-23 op (var) != XSIMPLEQ_END(head); \
354 6b191ed5 2021-02-23 op (var) = XSIMPLEQ_NEXT(head, var, field))
356 6b191ed5 2021-02-23 op #define XSIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \
357 6b191ed5 2021-02-23 op for ((var) = XSIMPLEQ_FIRST(head); \
358 6b191ed5 2021-02-23 op (var) && ((tvar) = XSIMPLEQ_NEXT(head, var, field), 1); \
359 6b191ed5 2021-02-23 op (var) = (tvar))
362 6b191ed5 2021-02-23 op * XOR Simple queue functions.
364 6b191ed5 2021-02-23 op #define XSIMPLEQ_INIT(head) do { \
365 6b191ed5 2021-02-23 op arc4random_buf(&(head)->sqx_cookie, sizeof((head)->sqx_cookie)); \
366 6b191ed5 2021-02-23 op (head)->sqx_first = XSIMPLEQ_XOR(head, NULL); \
367 6b191ed5 2021-02-23 op (head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \
370 6b191ed5 2021-02-23 op #define XSIMPLEQ_INSERT_HEAD(head, elm, field) do { \
371 6b191ed5 2021-02-23 op if (((elm)->field.sqx_next = (head)->sqx_first) == \
372 6b191ed5 2021-02-23 op XSIMPLEQ_XOR(head, NULL)) \
373 6b191ed5 2021-02-23 op (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \
374 6b191ed5 2021-02-23 op (head)->sqx_first = XSIMPLEQ_XOR(head, (elm)); \
377 6b191ed5 2021-02-23 op #define XSIMPLEQ_INSERT_TAIL(head, elm, field) do { \
378 6b191ed5 2021-02-23 op (elm)->field.sqx_next = XSIMPLEQ_XOR(head, NULL); \
379 6b191ed5 2021-02-23 op *(XSIMPLEQ_XOR(head, (head)->sqx_last)) = XSIMPLEQ_XOR(head, (elm)); \
380 6b191ed5 2021-02-23 op (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \
383 6b191ed5 2021-02-23 op #define XSIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
384 6b191ed5 2021-02-23 op if (((elm)->field.sqx_next = (listelm)->field.sqx_next) == \
385 6b191ed5 2021-02-23 op XSIMPLEQ_XOR(head, NULL)) \
386 6b191ed5 2021-02-23 op (head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \
387 6b191ed5 2021-02-23 op (listelm)->field.sqx_next = XSIMPLEQ_XOR(head, (elm)); \
390 6b191ed5 2021-02-23 op #define XSIMPLEQ_REMOVE_HEAD(head, field) do { \
391 6b191ed5 2021-02-23 op if (((head)->sqx_first = XSIMPLEQ_XOR(head, \
392 6b191ed5 2021-02-23 op (head)->sqx_first)->field.sqx_next) == XSIMPLEQ_XOR(head, NULL)) \
393 6b191ed5 2021-02-23 op (head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \
396 6b191ed5 2021-02-23 op #define XSIMPLEQ_REMOVE_AFTER(head, elm, field) do { \
397 6b191ed5 2021-02-23 op if (((elm)->field.sqx_next = XSIMPLEQ_XOR(head, \
398 6b191ed5 2021-02-23 op (elm)->field.sqx_next)->field.sqx_next) \
399 6b191ed5 2021-02-23 op == XSIMPLEQ_XOR(head, NULL)) \
400 6b191ed5 2021-02-23 op (head)->sqx_last = \
401 6b191ed5 2021-02-23 op XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \
406 6b191ed5 2021-02-23 op * Tail queue definitions.
408 6b191ed5 2021-02-23 op #define TAILQ_HEAD(name, type) \
409 6b191ed5 2021-02-23 op struct name { \
410 6b191ed5 2021-02-23 op struct type *tqh_first; /* first element */ \
411 6b191ed5 2021-02-23 op struct type **tqh_last; /* addr of last next element */ \
414 6b191ed5 2021-02-23 op #define TAILQ_HEAD_INITIALIZER(head) \
415 6b191ed5 2021-02-23 op { NULL, &(head).tqh_first }
417 6b191ed5 2021-02-23 op #define TAILQ_ENTRY(type) \
419 6b191ed5 2021-02-23 op struct type *tqe_next; /* next element */ \
420 6b191ed5 2021-02-23 op struct type **tqe_prev; /* address of previous next element */ \
424 6b191ed5 2021-02-23 op * Tail queue access methods.
426 6b191ed5 2021-02-23 op #define TAILQ_FIRST(head) ((head)->tqh_first)
427 6b191ed5 2021-02-23 op #define TAILQ_END(head) NULL
428 6b191ed5 2021-02-23 op #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
429 6b191ed5 2021-02-23 op #define TAILQ_LAST(head, headname) \
430 6b191ed5 2021-02-23 op (*(((struct headname *)((head)->tqh_last))->tqh_last))
432 6b191ed5 2021-02-23 op #define TAILQ_PREV(elm, headname, field) \
433 6b191ed5 2021-02-23 op (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
434 6b191ed5 2021-02-23 op #define TAILQ_EMPTY(head) \
435 6b191ed5 2021-02-23 op (TAILQ_FIRST(head) == TAILQ_END(head))
437 6b191ed5 2021-02-23 op #define TAILQ_FOREACH(var, head, field) \
438 6b191ed5 2021-02-23 op for((var) = TAILQ_FIRST(head); \
439 6b191ed5 2021-02-23 op (var) != TAILQ_END(head); \
440 6b191ed5 2021-02-23 op (var) = TAILQ_NEXT(var, field))
442 6b191ed5 2021-02-23 op #define TAILQ_FOREACH_SAFE(var, head, field, tvar) \
443 6b191ed5 2021-02-23 op for ((var) = TAILQ_FIRST(head); \
444 6b191ed5 2021-02-23 op (var) != TAILQ_END(head) && \
445 6b191ed5 2021-02-23 op ((tvar) = TAILQ_NEXT(var, field), 1); \
446 6b191ed5 2021-02-23 op (var) = (tvar))
449 6b191ed5 2021-02-23 op #define TAILQ_FOREACH_REVERSE(var, head, headname, field) \
450 6b191ed5 2021-02-23 op for((var) = TAILQ_LAST(head, headname); \
451 6b191ed5 2021-02-23 op (var) != TAILQ_END(head); \
452 6b191ed5 2021-02-23 op (var) = TAILQ_PREV(var, headname, field))
454 6b191ed5 2021-02-23 op #define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \
455 6b191ed5 2021-02-23 op for ((var) = TAILQ_LAST(head, headname); \
456 6b191ed5 2021-02-23 op (var) != TAILQ_END(head) && \
457 6b191ed5 2021-02-23 op ((tvar) = TAILQ_PREV(var, headname, field), 1); \
458 6b191ed5 2021-02-23 op (var) = (tvar))
461 6b191ed5 2021-02-23 op * Tail queue functions.
463 6b191ed5 2021-02-23 op #define TAILQ_INIT(head) do { \
464 6b191ed5 2021-02-23 op (head)->tqh_first = NULL; \
465 6b191ed5 2021-02-23 op (head)->tqh_last = &(head)->tqh_first; \
468 6b191ed5 2021-02-23 op #define TAILQ_INSERT_HEAD(head, elm, field) do { \
469 6b191ed5 2021-02-23 op if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \
470 6b191ed5 2021-02-23 op (head)->tqh_first->field.tqe_prev = \
471 6b191ed5 2021-02-23 op &(elm)->field.tqe_next; \
473 6b191ed5 2021-02-23 op (head)->tqh_last = &(elm)->field.tqe_next; \
474 6b191ed5 2021-02-23 op (head)->tqh_first = (elm); \
475 6b191ed5 2021-02-23 op (elm)->field.tqe_prev = &(head)->tqh_first; \
478 6b191ed5 2021-02-23 op #define TAILQ_INSERT_TAIL(head, elm, field) do { \
479 6b191ed5 2021-02-23 op (elm)->field.tqe_next = NULL; \
480 6b191ed5 2021-02-23 op (elm)->field.tqe_prev = (head)->tqh_last; \
481 6b191ed5 2021-02-23 op *(head)->tqh_last = (elm); \
482 6b191ed5 2021-02-23 op (head)->tqh_last = &(elm)->field.tqe_next; \
485 6b191ed5 2021-02-23 op #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
486 6b191ed5 2021-02-23 op if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
487 6b191ed5 2021-02-23 op (elm)->field.tqe_next->field.tqe_prev = \
488 6b191ed5 2021-02-23 op &(elm)->field.tqe_next; \
490 6b191ed5 2021-02-23 op (head)->tqh_last = &(elm)->field.tqe_next; \
491 6b191ed5 2021-02-23 op (listelm)->field.tqe_next = (elm); \
492 6b191ed5 2021-02-23 op (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
495 6b191ed5 2021-02-23 op #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \
496 6b191ed5 2021-02-23 op (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \
497 6b191ed5 2021-02-23 op (elm)->field.tqe_next = (listelm); \
498 6b191ed5 2021-02-23 op *(listelm)->field.tqe_prev = (elm); \
499 6b191ed5 2021-02-23 op (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \
502 6b191ed5 2021-02-23 op #define TAILQ_REMOVE(head, elm, field) do { \
503 6b191ed5 2021-02-23 op if (((elm)->field.tqe_next) != NULL) \
504 6b191ed5 2021-02-23 op (elm)->field.tqe_next->field.tqe_prev = \
505 6b191ed5 2021-02-23 op (elm)->field.tqe_prev; \
507 6b191ed5 2021-02-23 op (head)->tqh_last = (elm)->field.tqe_prev; \
508 6b191ed5 2021-02-23 op *(elm)->field.tqe_prev = (elm)->field.tqe_next; \
509 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.tqe_prev); \
510 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.tqe_next); \
513 6b191ed5 2021-02-23 op #define TAILQ_REPLACE(head, elm, elm2, field) do { \
514 6b191ed5 2021-02-23 op if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \
515 6b191ed5 2021-02-23 op (elm2)->field.tqe_next->field.tqe_prev = \
516 6b191ed5 2021-02-23 op &(elm2)->field.tqe_next; \
518 6b191ed5 2021-02-23 op (head)->tqh_last = &(elm2)->field.tqe_next; \
519 6b191ed5 2021-02-23 op (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \
520 6b191ed5 2021-02-23 op *(elm2)->field.tqe_prev = (elm2); \
521 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.tqe_prev); \
522 6b191ed5 2021-02-23 op _Q_INVALIDATE((elm)->field.tqe_next); \
525 6b191ed5 2021-02-23 op #define TAILQ_CONCAT(head1, head2, field) do { \
526 6b191ed5 2021-02-23 op if (!TAILQ_EMPTY(head2)) { \
527 6b191ed5 2021-02-23 op *(head1)->tqh_last = (head2)->tqh_first; \
528 6b191ed5 2021-02-23 op (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \
529 6b191ed5 2021-02-23 op (head1)->tqh_last = (head2)->tqh_last; \
530 6b191ed5 2021-02-23 op TAILQ_INIT((head2)); \
534 6b191ed5 2021-02-23 op #endif /* !_SYS_QUEUE_H_ */
