1/* OPENBSD ORIGINAL: sys/sys/queue.h */
2
3/* $OpenBSD: queue.h,v 1.25 2004/04/08 16:08:21 henning Exp $ */
4/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */
5
6/*
7 * Copyright (c) 1991, 1993
8 * The Regents of the University of California. All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)queue.h 8.5 (Berkeley) 8/20/94
35 */
36
37#ifndef _FAKE_QUEUE_H_
38#define _FAKE_QUEUE_H_
39
40/*
41 * Require for OS/X and other platforms that have old/broken/incomplete
42 * <sys/queue.h>.
43 */
44#undef SLIST_HEAD
45#undef SLIST_HEAD_INITIALIZER
46#undef SLIST_ENTRY
47#undef SLIST_FOREACH_PREVPTR
48#undef SLIST_FIRST
49#undef SLIST_END
50#undef SLIST_EMPTY
51#undef SLIST_NEXT
52#undef SLIST_FOREACH
53#undef SLIST_INIT
54#undef SLIST_INSERT_AFTER
55#undef SLIST_INSERT_HEAD
56#undef SLIST_REMOVE_HEAD
57#undef SLIST_REMOVE
58#undef SLIST_REMOVE_NEXT
59#undef LIST_HEAD
60#undef LIST_HEAD_INITIALIZER
61#undef LIST_ENTRY
62#undef LIST_FIRST
63#undef LIST_END
64#undef LIST_EMPTY
65#undef LIST_NEXT
66#undef LIST_FOREACH
67#undef LIST_INIT
68#undef LIST_INSERT_AFTER
69#undef LIST_INSERT_BEFORE
70#undef LIST_INSERT_HEAD
71#undef LIST_REMOVE
72#undef LIST_REPLACE
73#undef SIMPLEQ_HEAD
74#undef SIMPLEQ_HEAD_INITIALIZER
75#undef SIMPLEQ_ENTRY
76#undef SIMPLEQ_FIRST
77#undef SIMPLEQ_END
78#undef SIMPLEQ_EMPTY
79#undef SIMPLEQ_NEXT
80#undef SIMPLEQ_FOREACH
81#undef SIMPLEQ_INIT
82#undef SIMPLEQ_INSERT_HEAD
83#undef SIMPLEQ_INSERT_TAIL
84#undef SIMPLEQ_INSERT_AFTER
85#undef SIMPLEQ_REMOVE_HEAD
86#undef TAILQ_HEAD
87#undef TAILQ_HEAD_INITIALIZER
88#undef TAILQ_ENTRY
89#undef TAILQ_FIRST
90#undef TAILQ_END
91#undef TAILQ_NEXT
92#undef TAILQ_LAST
93#undef TAILQ_PREV
94#undef TAILQ_EMPTY
95#undef TAILQ_FOREACH
96#undef TAILQ_FOREACH_REVERSE
97#undef TAILQ_INIT
98#undef TAILQ_INSERT_HEAD
99#undef TAILQ_INSERT_TAIL
100#undef TAILQ_INSERT_AFTER
101#undef TAILQ_INSERT_BEFORE
102#undef TAILQ_REMOVE
103#undef TAILQ_REPLACE
104#undef CIRCLEQ_HEAD
105#undef CIRCLEQ_HEAD_INITIALIZER
106#undef CIRCLEQ_ENTRY
107#undef CIRCLEQ_FIRST
108#undef CIRCLEQ_LAST
109#undef CIRCLEQ_END
110#undef CIRCLEQ_NEXT
111#undef CIRCLEQ_PREV
112#undef CIRCLEQ_EMPTY
113#undef CIRCLEQ_FOREACH
114#undef CIRCLEQ_FOREACH_REVERSE
115#undef CIRCLEQ_INIT
116#undef CIRCLEQ_INSERT_AFTER
117#undef CIRCLEQ_INSERT_BEFORE
118#undef CIRCLEQ_INSERT_HEAD
119#undef CIRCLEQ_INSERT_TAIL
120#undef CIRCLEQ_REMOVE
121#undef CIRCLEQ_REPLACE
122
123/*
124 * This file defines five types of data structures: singly-linked lists,
125 * lists, simple queues, tail queues, and circular queues.
126 *
127 *
128 * A singly-linked list is headed by a single forward pointer. The elements
129 * are singly linked for minimum space and pointer manipulation overhead at
130 * the expense of O(n) removal for arbitrary elements. New elements can be
131 * added to the list after an existing element or at the head of the list.
132 * Elements being removed from the head of the list should use the explicit
133 * macro for this purpose for optimum efficiency. A singly-linked list may
134 * only be traversed in the forward direction. Singly-linked lists are ideal
135 * for applications with large datasets and few or no removals or for
136 * implementing a LIFO queue.
137 *
138 * A list is headed by a single forward pointer (or an array of forward
139 * pointers for a hash table header). The elements are doubly linked
140 * so that an arbitrary element can be removed without a need to
141 * traverse the list. New elements can be added to the list before
142 * or after an existing element or at the head of the list. A list
143 * may only be traversed in the forward direction.
144 *
145 * A simple queue is headed by a pair of pointers, one the head of the
146 * list and the other to the tail of the list. The elements are singly
147 * linked to save space, so elements can only be removed from the
148 * head of the list. New elements can be added to the list before or after
149 * an existing element, at the head of the list, or at the end of the
150 * list. A simple queue may only be traversed in the forward direction.
151 *
152 * A tail queue is headed by a pair of pointers, one to the head of the
153 * list and the other to the tail of the list. The elements are doubly
154 * linked so that an arbitrary element can be removed without a need to
155 * traverse the list. New elements can be added to the list before or
156 * after an existing element, at the head of the list, or at the end of
157 * the list. A tail queue may be traversed in either direction.
158 *
159 * A circle queue is headed by a pair of pointers, one to the head of the
160 * list and the other to the tail of the list. The elements are doubly
161 * linked so that an arbitrary element can be removed without a need to
162 * traverse the list. New elements can be added to the list before or after
163 * an existing element, at the head of the list, or at the end of the list.
164 * A circle queue may be traversed in either direction, but has a more
165 * complex end of list detection.
166 *
167 * For details on the use of these macros, see the queue(3) manual page.
168 */
169
170/*
171 * Singly-linked List definitions.
172 */
173#define SLIST_HEAD(name, type) \
174struct name { \
175 struct type *slh_first; /* first element */ \
176}
177
178#define SLIST_HEAD_INITIALIZER(head) \
179 { NULL }
180
181#define SLIST_ENTRY(type) \
182struct { \
183 struct type *sle_next; /* next element */ \
184}
185
186/*
187 * Singly-linked List access methods.
188 */
189#define SLIST_FIRST(head) ((head)->slh_first)
190#define SLIST_END(head) NULL
191#define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head))
192#define SLIST_NEXT(elm, field) ((elm)->field.sle_next)
193
194#define SLIST_FOREACH(var, head, field) \
195 for((var) = SLIST_FIRST(head); \
196 (var) != SLIST_END(head); \
197 (var) = SLIST_NEXT(var, field))
198
199#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \
200 for ((varp) = &SLIST_FIRST((head)); \
201 ((var) = *(varp)) != SLIST_END(head); \
202 (varp) = &SLIST_NEXT((var), field))
203
204/*
205 * Singly-linked List functions.
206 */
207#define SLIST_INIT(head) { \
208 SLIST_FIRST(head) = SLIST_END(head); \
209}
210
211#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
212 (elm)->field.sle_next = (slistelm)->field.sle_next; \
213 (slistelm)->field.sle_next = (elm); \
214} while (0)
215
216#define SLIST_INSERT_HEAD(head, elm, field) do { \
217 (elm)->field.sle_next = (head)->slh_first; \
218 (head)->slh_first = (elm); \
219} while (0)
220
221#define SLIST_REMOVE_NEXT(head, elm, field) do { \
222 (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \
223} while (0)
224
225#define SLIST_REMOVE_HEAD(head, field) do { \
226 (head)->slh_first = (head)->slh_first->field.sle_next; \
227} while (0)
228
229#define SLIST_REMOVE(head, elm, type, field) do { \
230 if ((head)->slh_first == (elm)) { \
231 SLIST_REMOVE_HEAD((head), field); \
232 } \
233 else { \
234 struct type *curelm = (head)->slh_first; \
235 while( curelm->field.sle_next != (elm) ) \
236 curelm = curelm->field.sle_next; \
237 curelm->field.sle_next = \
238 curelm->field.sle_next->field.sle_next; \
239 } \
240} while (0)
241
242/*
243 * List definitions.
244 */
245#define LIST_HEAD(name, type) \
246struct name { \
247 struct type *lh_first; /* first element */ \
248}
249
250#define LIST_HEAD_INITIALIZER(head) \
251 { NULL }
252
253#define LIST_ENTRY(type) \
254struct { \
255 struct type *le_next; /* next element */ \
256 struct type **le_prev; /* address of previous next element */ \
257}
258
259/*
260 * List access methods
261 */
262#define LIST_FIRST(head) ((head)->lh_first)
263#define LIST_END(head) NULL
264#define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head))
265#define LIST_NEXT(elm, field) ((elm)->field.le_next)
266
267#define LIST_FOREACH(var, head, field) \
268 for((var) = LIST_FIRST(head); \
269 (var)!= LIST_END(head); \
270 (var) = LIST_NEXT(var, field))
271
272/*
273 * List functions.
274 */
275#define LIST_INIT(head) do { \
276 LIST_FIRST(head) = LIST_END(head); \
277} while (0)
278
279#define LIST_INSERT_AFTER(listelm, elm, field) do { \
280 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \
281 (listelm)->field.le_next->field.le_prev = \
282 &(elm)->field.le_next; \
283 (listelm)->field.le_next = (elm); \
284 (elm)->field.le_prev = &(listelm)->field.le_next; \
285} while (0)
286
287#define LIST_INSERT_BEFORE(listelm, elm, field) do { \
288 (elm)->field.le_prev = (listelm)->field.le_prev; \
289 (elm)->field.le_next = (listelm); \
290 *(listelm)->field.le_prev = (elm); \
291 (listelm)->field.le_prev = &(elm)->field.le_next; \
292} while (0)
293
294#define LIST_INSERT_HEAD(head, elm, field) do { \
295 if (((elm)->field.le_next = (head)->lh_first) != NULL) \
296 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\
297 (head)->lh_first = (elm); \
298 (elm)->field.le_prev = &(head)->lh_first; \
299} while (0)
300
301#define LIST_REMOVE(elm, field) do { \
302 if ((elm)->field.le_next != NULL) \
303 (elm)->field.le_next->field.le_prev = \
304 (elm)->field.le_prev; \
305 *(elm)->field.le_prev = (elm)->field.le_next; \
306} while (0)
307
308#define LIST_REPLACE(elm, elm2, field) do { \
309 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \
310 (elm2)->field.le_next->field.le_prev = \
311 &(elm2)->field.le_next; \
312 (elm2)->field.le_prev = (elm)->field.le_prev; \
313 *(elm2)->field.le_prev = (elm2); \
314} while (0)
315
316/*
317 * Simple queue definitions.
318 */
319#define SIMPLEQ_HEAD(name, type) \
320struct name { \
321 struct type *sqh_first; /* first element */ \
322 struct type **sqh_last; /* addr of last next element */ \
323}
324
325#define SIMPLEQ_HEAD_INITIALIZER(head) \
326 { NULL, &(head).sqh_first }
327
328#define SIMPLEQ_ENTRY(type) \
329struct { \
330 struct type *sqe_next; /* next element */ \
331}
332
333/*
334 * Simple queue access methods.
335 */
336#define SIMPLEQ_FIRST(head) ((head)->sqh_first)
337#define SIMPLEQ_END(head) NULL
338#define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
339#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next)
340
341#define SIMPLEQ_FOREACH(var, head, field) \
342 for((var) = SIMPLEQ_FIRST(head); \
343 (var) != SIMPLEQ_END(head); \
344 (var) = SIMPLEQ_NEXT(var, field))
345
346/*
347 * Simple queue functions.
348 */
349#define SIMPLEQ_INIT(head) do { \
350 (head)->sqh_first = NULL; \
351 (head)->sqh_last = &(head)->sqh_first; \
352} while (0)
353
354#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \
355 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \
356 (head)->sqh_last = &(elm)->field.sqe_next; \
357 (head)->sqh_first = (elm); \
358} while (0)
359
360#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \
361 (elm)->field.sqe_next = NULL; \
362 *(head)->sqh_last = (elm); \
363 (head)->sqh_last = &(elm)->field.sqe_next; \
364} while (0)
365
366#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
367 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
368 (head)->sqh_last = &(elm)->field.sqe_next; \
369 (listelm)->field.sqe_next = (elm); \
370} while (0)
371
372#define SIMPLEQ_REMOVE_HEAD(head, elm, field) do { \
373 if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) \
374 (head)->sqh_last = &(head)->sqh_first; \
375} while (0)
376
377/*
378 * Tail queue definitions.
379 */
380#define TAILQ_HEAD(name, type) \
381struct name { \
382 struct type *tqh_first; /* first element */ \
383 struct type **tqh_last; /* addr of last next element */ \
384}
385
386#define TAILQ_HEAD_INITIALIZER(head) \
387 { NULL, &(head).tqh_first }
388
389#define TAILQ_ENTRY(type) \
390struct { \
391 struct type *tqe_next; /* next element */ \
392 struct type **tqe_prev; /* address of previous next element */ \
393}
394
395/*
396 * tail queue access methods
397 */
398#define TAILQ_FIRST(head) ((head)->tqh_first)
399#define TAILQ_END(head) NULL
400#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
401#define TAILQ_LAST(head, headname) \
402 (*(((struct headname *)((head)->tqh_last))->tqh_last))
403/* XXX */
404#define TAILQ_PREV(elm, headname, field) \
405 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
406#define TAILQ_EMPTY(head) \
407 (TAILQ_FIRST(head) == TAILQ_END(head))
408
409#define TAILQ_FOREACH(var, head, field) \
410 for((var) = TAILQ_FIRST(head); \
411 (var) != TAILQ_END(head); \
412 (var) = TAILQ_NEXT(var, field))
413
414#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \
415 for((var) = TAILQ_LAST(head, headname); \
416 (var) != TAILQ_END(head); \
417 (var) = TAILQ_PREV(var, headname, field))
418
419/*
420 * Tail queue functions.
421 */
422#define TAILQ_INIT(head) do { \
423 (head)->tqh_first = NULL; \
424 (head)->tqh_last = &(head)->tqh_first; \
425} while (0)
426
427#define TAILQ_INSERT_HEAD(head, elm, field) do { \
428 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \
429 (head)->tqh_first->field.tqe_prev = \
430 &(elm)->field.tqe_next; \
431 else \
432 (head)->tqh_last = &(elm)->field.tqe_next; \
433 (head)->tqh_first = (elm); \
434 (elm)->field.tqe_prev = &(head)->tqh_first; \
435} while (0)
436
437#define TAILQ_INSERT_TAIL(head, elm, field) do { \
438 (elm)->field.tqe_next = NULL; \
439 (elm)->field.tqe_prev = (head)->tqh_last; \
440 *(head)->tqh_last = (elm); \
441 (head)->tqh_last = &(elm)->field.tqe_next; \
442} while (0)
443
444#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
445 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
446 (elm)->field.tqe_next->field.tqe_prev = \
447 &(elm)->field.tqe_next; \
448 else \
449 (head)->tqh_last = &(elm)->field.tqe_next; \
450 (listelm)->field.tqe_next = (elm); \
451 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
452} while (0)
453
454#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \
455 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \
456 (elm)->field.tqe_next = (listelm); \
457 *(listelm)->field.tqe_prev = (elm); \
458 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \
459} while (0)
460
461#define TAILQ_REMOVE(head, elm, field) do { \
462 if (((elm)->field.tqe_next) != NULL) \
463 (elm)->field.tqe_next->field.tqe_prev = \
464 (elm)->field.tqe_prev; \
465 else \
466 (head)->tqh_last = (elm)->field.tqe_prev; \
467 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \
468} while (0)
469
470#define TAILQ_REPLACE(head, elm, elm2, field) do { \
471 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \
472 (elm2)->field.tqe_next->field.tqe_prev = \
473 &(elm2)->field.tqe_next; \
474 else \
475 (head)->tqh_last = &(elm2)->field.tqe_next; \
476 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \
477 *(elm2)->field.tqe_prev = (elm2); \
478} while (0)
479
480/*
481 * Circular queue definitions.
482 */
483#define CIRCLEQ_HEAD(name, type) \
484struct name { \
485 struct type *cqh_first; /* first element */ \
486 struct type *cqh_last; /* last element */ \
487}
488
489#define CIRCLEQ_HEAD_INITIALIZER(head) \
490 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) }
491
492#define CIRCLEQ_ENTRY(type) \
493struct { \
494 struct type *cqe_next; /* next element */ \
495 struct type *cqe_prev; /* previous element */ \
496}
497
498/*
499 * Circular queue access methods
500 */
501#define CIRCLEQ_FIRST(head) ((head)->cqh_first)
502#define CIRCLEQ_LAST(head) ((head)->cqh_last)
503#define CIRCLEQ_END(head) ((void *)(head))
504#define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next)
505#define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev)
506#define CIRCLEQ_EMPTY(head) \
507 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head))
508
509#define CIRCLEQ_FOREACH(var, head, field) \
510 for((var) = CIRCLEQ_FIRST(head); \
511 (var) != CIRCLEQ_END(head); \
512 (var) = CIRCLEQ_NEXT(var, field))
513
514#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \
515 for((var) = CIRCLEQ_LAST(head); \
516 (var) != CIRCLEQ_END(head); \
517 (var) = CIRCLEQ_PREV(var, field))
518
519/*
520 * Circular queue functions.
521 */
522#define CIRCLEQ_INIT(head) do { \
523 (head)->cqh_first = CIRCLEQ_END(head); \
524 (head)->cqh_last = CIRCLEQ_END(head); \
525} while (0)
526
527#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
528 (elm)->field.cqe_next = (listelm)->field.cqe_next; \
529 (elm)->field.cqe_prev = (listelm); \
530 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \
531 (head)->cqh_last = (elm); \
532 else \
533 (listelm)->field.cqe_next->field.cqe_prev = (elm); \
534 (listelm)->field.cqe_next = (elm); \
535} while (0)
536
537#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \
538 (elm)->field.cqe_next = (listelm); \
539 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \
540 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \
541 (head)->cqh_first = (elm); \
542 else \
543 (listelm)->field.cqe_prev->field.cqe_next = (elm); \
544 (listelm)->field.cqe_prev = (elm); \
545} while (0)
546
547#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \
548 (elm)->field.cqe_next = (head)->cqh_first; \
549 (elm)->field.cqe_prev = CIRCLEQ_END(head); \
550 if ((head)->cqh_last == CIRCLEQ_END(head)) \
551 (head)->cqh_last = (elm); \
552 else \
553 (head)->cqh_first->field.cqe_prev = (elm); \
554 (head)->cqh_first = (elm); \
555} while (0)
556
557#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \
558 (elm)->field.cqe_next = CIRCLEQ_END(head); \
559 (elm)->field.cqe_prev = (head)->cqh_last; \
560 if ((head)->cqh_first == CIRCLEQ_END(head)) \
561 (head)->cqh_first = (elm); \
562 else \
563 (head)->cqh_last->field.cqe_next = (elm); \
564 (head)->cqh_last = (elm); \
565} while (0)
566
567#define CIRCLEQ_REMOVE(head, elm, field) do { \
568 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \
569 (head)->cqh_last = (elm)->field.cqe_prev; \
570 else \
571 (elm)->field.cqe_next->field.cqe_prev = \
572 (elm)->field.cqe_prev; \
573 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \
574 (head)->cqh_first = (elm)->field.cqe_next; \
575 else \
576 (elm)->field.cqe_prev->field.cqe_next = \
577 (elm)->field.cqe_next; \
578} while (0)
579
580#define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \
581 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \
582 CIRCLEQ_END(head)) \
583 (head).cqh_last = (elm2); \
584 else \
585 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \
586 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \
587 CIRCLEQ_END(head)) \
588 (head).cqh_first = (elm2); \
589 else \
590 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \
591} while (0)
592
593#endif /* !_FAKE_QUEUE_H_ */
2
3/* $OpenBSD: queue.h,v 1.25 2004/04/08 16:08:21 henning Exp $ */
4/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */
5
6/*
7 * Copyright (c) 1991, 1993
8 * The Regents of the University of California. All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)queue.h 8.5 (Berkeley) 8/20/94
35 */
36
37#ifndef _FAKE_QUEUE_H_
38#define _FAKE_QUEUE_H_
39
40/*
41 * Require for OS/X and other platforms that have old/broken/incomplete
42 * <sys/queue.h>.
43 */
44#undef SLIST_HEAD
45#undef SLIST_HEAD_INITIALIZER
46#undef SLIST_ENTRY
47#undef SLIST_FOREACH_PREVPTR
48#undef SLIST_FIRST
49#undef SLIST_END
50#undef SLIST_EMPTY
51#undef SLIST_NEXT
52#undef SLIST_FOREACH
53#undef SLIST_INIT
54#undef SLIST_INSERT_AFTER
55#undef SLIST_INSERT_HEAD
56#undef SLIST_REMOVE_HEAD
57#undef SLIST_REMOVE
58#undef SLIST_REMOVE_NEXT
59#undef LIST_HEAD
60#undef LIST_HEAD_INITIALIZER
61#undef LIST_ENTRY
62#undef LIST_FIRST
63#undef LIST_END
64#undef LIST_EMPTY
65#undef LIST_NEXT
66#undef LIST_FOREACH
67#undef LIST_INIT
68#undef LIST_INSERT_AFTER
69#undef LIST_INSERT_BEFORE
70#undef LIST_INSERT_HEAD
71#undef LIST_REMOVE
72#undef LIST_REPLACE
73#undef SIMPLEQ_HEAD
74#undef SIMPLEQ_HEAD_INITIALIZER
75#undef SIMPLEQ_ENTRY
76#undef SIMPLEQ_FIRST
77#undef SIMPLEQ_END
78#undef SIMPLEQ_EMPTY
79#undef SIMPLEQ_NEXT
80#undef SIMPLEQ_FOREACH
81#undef SIMPLEQ_INIT
82#undef SIMPLEQ_INSERT_HEAD
83#undef SIMPLEQ_INSERT_TAIL
84#undef SIMPLEQ_INSERT_AFTER
85#undef SIMPLEQ_REMOVE_HEAD
86#undef TAILQ_HEAD
87#undef TAILQ_HEAD_INITIALIZER
88#undef TAILQ_ENTRY
89#undef TAILQ_FIRST
90#undef TAILQ_END
91#undef TAILQ_NEXT
92#undef TAILQ_LAST
93#undef TAILQ_PREV
94#undef TAILQ_EMPTY
95#undef TAILQ_FOREACH
96#undef TAILQ_FOREACH_REVERSE
97#undef TAILQ_INIT
98#undef TAILQ_INSERT_HEAD
99#undef TAILQ_INSERT_TAIL
100#undef TAILQ_INSERT_AFTER
101#undef TAILQ_INSERT_BEFORE
102#undef TAILQ_REMOVE
103#undef TAILQ_REPLACE
104#undef CIRCLEQ_HEAD
105#undef CIRCLEQ_HEAD_INITIALIZER
106#undef CIRCLEQ_ENTRY
107#undef CIRCLEQ_FIRST
108#undef CIRCLEQ_LAST
109#undef CIRCLEQ_END
110#undef CIRCLEQ_NEXT
111#undef CIRCLEQ_PREV
112#undef CIRCLEQ_EMPTY
113#undef CIRCLEQ_FOREACH
114#undef CIRCLEQ_FOREACH_REVERSE
115#undef CIRCLEQ_INIT
116#undef CIRCLEQ_INSERT_AFTER
117#undef CIRCLEQ_INSERT_BEFORE
118#undef CIRCLEQ_INSERT_HEAD
119#undef CIRCLEQ_INSERT_TAIL
120#undef CIRCLEQ_REMOVE
121#undef CIRCLEQ_REPLACE
122
123/*
124 * This file defines five types of data structures: singly-linked lists,
125 * lists, simple queues, tail queues, and circular queues.
126 *
127 *
128 * A singly-linked list is headed by a single forward pointer. The elements
129 * are singly linked for minimum space and pointer manipulation overhead at
130 * the expense of O(n) removal for arbitrary elements. New elements can be
131 * added to the list after an existing element or at the head of the list.
132 * Elements being removed from the head of the list should use the explicit
133 * macro for this purpose for optimum efficiency. A singly-linked list may
134 * only be traversed in the forward direction. Singly-linked lists are ideal
135 * for applications with large datasets and few or no removals or for
136 * implementing a LIFO queue.
137 *
138 * A list is headed by a single forward pointer (or an array of forward
139 * pointers for a hash table header). The elements are doubly linked
140 * so that an arbitrary element can be removed without a need to
141 * traverse the list. New elements can be added to the list before
142 * or after an existing element or at the head of the list. A list
143 * may only be traversed in the forward direction.
144 *
145 * A simple queue is headed by a pair of pointers, one the head of the
146 * list and the other to the tail of the list. The elements are singly
147 * linked to save space, so elements can only be removed from the
148 * head of the list. New elements can be added to the list before or after
149 * an existing element, at the head of the list, or at the end of the
150 * list. A simple queue may only be traversed in the forward direction.
151 *
152 * A tail queue is headed by a pair of pointers, one to the head of the
153 * list and the other to the tail of the list. The elements are doubly
154 * linked so that an arbitrary element can be removed without a need to
155 * traverse the list. New elements can be added to the list before or
156 * after an existing element, at the head of the list, or at the end of
157 * the list. A tail queue may be traversed in either direction.
158 *
159 * A circle queue is headed by a pair of pointers, one to the head of the
160 * list and the other to the tail of the list. The elements are doubly
161 * linked so that an arbitrary element can be removed without a need to
162 * traverse the list. New elements can be added to the list before or after
163 * an existing element, at the head of the list, or at the end of the list.
164 * A circle queue may be traversed in either direction, but has a more
165 * complex end of list detection.
166 *
167 * For details on the use of these macros, see the queue(3) manual page.
168 */
169
170/*
171 * Singly-linked List definitions.
172 */
173#define SLIST_HEAD(name, type) \
174struct name { \
175 struct type *slh_first; /* first element */ \
176}
177
178#define SLIST_HEAD_INITIALIZER(head) \
179 { NULL }
180
181#define SLIST_ENTRY(type) \
182struct { \
183 struct type *sle_next; /* next element */ \
184}
185
186/*
187 * Singly-linked List access methods.
188 */
189#define SLIST_FIRST(head) ((head)->slh_first)
190#define SLIST_END(head) NULL
191#define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head))
192#define SLIST_NEXT(elm, field) ((elm)->field.sle_next)
193
194#define SLIST_FOREACH(var, head, field) \
195 for((var) = SLIST_FIRST(head); \
196 (var) != SLIST_END(head); \
197 (var) = SLIST_NEXT(var, field))
198
199#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \
200 for ((varp) = &SLIST_FIRST((head)); \
201 ((var) = *(varp)) != SLIST_END(head); \
202 (varp) = &SLIST_NEXT((var), field))
203
204/*
205 * Singly-linked List functions.
206 */
207#define SLIST_INIT(head) { \
208 SLIST_FIRST(head) = SLIST_END(head); \
209}
210
211#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \
212 (elm)->field.sle_next = (slistelm)->field.sle_next; \
213 (slistelm)->field.sle_next = (elm); \
214} while (0)
215
216#define SLIST_INSERT_HEAD(head, elm, field) do { \
217 (elm)->field.sle_next = (head)->slh_first; \
218 (head)->slh_first = (elm); \
219} while (0)
220
221#define SLIST_REMOVE_NEXT(head, elm, field) do { \
222 (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \
223} while (0)
224
225#define SLIST_REMOVE_HEAD(head, field) do { \
226 (head)->slh_first = (head)->slh_first->field.sle_next; \
227} while (0)
228
229#define SLIST_REMOVE(head, elm, type, field) do { \
230 if ((head)->slh_first == (elm)) { \
231 SLIST_REMOVE_HEAD((head), field); \
232 } \
233 else { \
234 struct type *curelm = (head)->slh_first; \
235 while( curelm->field.sle_next != (elm) ) \
236 curelm = curelm->field.sle_next; \
237 curelm->field.sle_next = \
238 curelm->field.sle_next->field.sle_next; \
239 } \
240} while (0)
241
242/*
243 * List definitions.
244 */
245#define LIST_HEAD(name, type) \
246struct name { \
247 struct type *lh_first; /* first element */ \
248}
249
250#define LIST_HEAD_INITIALIZER(head) \
251 { NULL }
252
253#define LIST_ENTRY(type) \
254struct { \
255 struct type *le_next; /* next element */ \
256 struct type **le_prev; /* address of previous next element */ \
257}
258
259/*
260 * List access methods
261 */
262#define LIST_FIRST(head) ((head)->lh_first)
263#define LIST_END(head) NULL
264#define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head))
265#define LIST_NEXT(elm, field) ((elm)->field.le_next)
266
267#define LIST_FOREACH(var, head, field) \
268 for((var) = LIST_FIRST(head); \
269 (var)!= LIST_END(head); \
270 (var) = LIST_NEXT(var, field))
271
272/*
273 * List functions.
274 */
275#define LIST_INIT(head) do { \
276 LIST_FIRST(head) = LIST_END(head); \
277} while (0)
278
279#define LIST_INSERT_AFTER(listelm, elm, field) do { \
280 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \
281 (listelm)->field.le_next->field.le_prev = \
282 &(elm)->field.le_next; \
283 (listelm)->field.le_next = (elm); \
284 (elm)->field.le_prev = &(listelm)->field.le_next; \
285} while (0)
286
287#define LIST_INSERT_BEFORE(listelm, elm, field) do { \
288 (elm)->field.le_prev = (listelm)->field.le_prev; \
289 (elm)->field.le_next = (listelm); \
290 *(listelm)->field.le_prev = (elm); \
291 (listelm)->field.le_prev = &(elm)->field.le_next; \
292} while (0)
293
294#define LIST_INSERT_HEAD(head, elm, field) do { \
295 if (((elm)->field.le_next = (head)->lh_first) != NULL) \
296 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\
297 (head)->lh_first = (elm); \
298 (elm)->field.le_prev = &(head)->lh_first; \
299} while (0)
300
301#define LIST_REMOVE(elm, field) do { \
302 if ((elm)->field.le_next != NULL) \
303 (elm)->field.le_next->field.le_prev = \
304 (elm)->field.le_prev; \
305 *(elm)->field.le_prev = (elm)->field.le_next; \
306} while (0)
307
308#define LIST_REPLACE(elm, elm2, field) do { \
309 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \
310 (elm2)->field.le_next->field.le_prev = \
311 &(elm2)->field.le_next; \
312 (elm2)->field.le_prev = (elm)->field.le_prev; \
313 *(elm2)->field.le_prev = (elm2); \
314} while (0)
315
316/*
317 * Simple queue definitions.
318 */
319#define SIMPLEQ_HEAD(name, type) \
320struct name { \
321 struct type *sqh_first; /* first element */ \
322 struct type **sqh_last; /* addr of last next element */ \
323}
324
325#define SIMPLEQ_HEAD_INITIALIZER(head) \
326 { NULL, &(head).sqh_first }
327
328#define SIMPLEQ_ENTRY(type) \
329struct { \
330 struct type *sqe_next; /* next element */ \
331}
332
333/*
334 * Simple queue access methods.
335 */
336#define SIMPLEQ_FIRST(head) ((head)->sqh_first)
337#define SIMPLEQ_END(head) NULL
338#define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
339#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next)
340
341#define SIMPLEQ_FOREACH(var, head, field) \
342 for((var) = SIMPLEQ_FIRST(head); \
343 (var) != SIMPLEQ_END(head); \
344 (var) = SIMPLEQ_NEXT(var, field))
345
346/*
347 * Simple queue functions.
348 */
349#define SIMPLEQ_INIT(head) do { \
350 (head)->sqh_first = NULL; \
351 (head)->sqh_last = &(head)->sqh_first; \
352} while (0)
353
354#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \
355 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \
356 (head)->sqh_last = &(elm)->field.sqe_next; \
357 (head)->sqh_first = (elm); \
358} while (0)
359
360#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \
361 (elm)->field.sqe_next = NULL; \
362 *(head)->sqh_last = (elm); \
363 (head)->sqh_last = &(elm)->field.sqe_next; \
364} while (0)
365
366#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
367 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
368 (head)->sqh_last = &(elm)->field.sqe_next; \
369 (listelm)->field.sqe_next = (elm); \
370} while (0)
371
372#define SIMPLEQ_REMOVE_HEAD(head, elm, field) do { \
373 if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) \
374 (head)->sqh_last = &(head)->sqh_first; \
375} while (0)
376
377/*
378 * Tail queue definitions.
379 */
380#define TAILQ_HEAD(name, type) \
381struct name { \
382 struct type *tqh_first; /* first element */ \
383 struct type **tqh_last; /* addr of last next element */ \
384}
385
386#define TAILQ_HEAD_INITIALIZER(head) \
387 { NULL, &(head).tqh_first }
388
389#define TAILQ_ENTRY(type) \
390struct { \
391 struct type *tqe_next; /* next element */ \
392 struct type **tqe_prev; /* address of previous next element */ \
393}
394
395/*
396 * tail queue access methods
397 */
398#define TAILQ_FIRST(head) ((head)->tqh_first)
399#define TAILQ_END(head) NULL
400#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next)
401#define TAILQ_LAST(head, headname) \
402 (*(((struct headname *)((head)->tqh_last))->tqh_last))
403/* XXX */
404#define TAILQ_PREV(elm, headname, field) \
405 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
406#define TAILQ_EMPTY(head) \
407 (TAILQ_FIRST(head) == TAILQ_END(head))
408
409#define TAILQ_FOREACH(var, head, field) \
410 for((var) = TAILQ_FIRST(head); \
411 (var) != TAILQ_END(head); \
412 (var) = TAILQ_NEXT(var, field))
413
414#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \
415 for((var) = TAILQ_LAST(head, headname); \
416 (var) != TAILQ_END(head); \
417 (var) = TAILQ_PREV(var, headname, field))
418
419/*
420 * Tail queue functions.
421 */
422#define TAILQ_INIT(head) do { \
423 (head)->tqh_first = NULL; \
424 (head)->tqh_last = &(head)->tqh_first; \
425} while (0)
426
427#define TAILQ_INSERT_HEAD(head, elm, field) do { \
428 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \
429 (head)->tqh_first->field.tqe_prev = \
430 &(elm)->field.tqe_next; \
431 else \
432 (head)->tqh_last = &(elm)->field.tqe_next; \
433 (head)->tqh_first = (elm); \
434 (elm)->field.tqe_prev = &(head)->tqh_first; \
435} while (0)
436
437#define TAILQ_INSERT_TAIL(head, elm, field) do { \
438 (elm)->field.tqe_next = NULL; \
439 (elm)->field.tqe_prev = (head)->tqh_last; \
440 *(head)->tqh_last = (elm); \
441 (head)->tqh_last = &(elm)->field.tqe_next; \
442} while (0)
443
444#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \
445 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
446 (elm)->field.tqe_next->field.tqe_prev = \
447 &(elm)->field.tqe_next; \
448 else \
449 (head)->tqh_last = &(elm)->field.tqe_next; \
450 (listelm)->field.tqe_next = (elm); \
451 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \
452} while (0)
453
454#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \
455 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \
456 (elm)->field.tqe_next = (listelm); \
457 *(listelm)->field.tqe_prev = (elm); \
458 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \
459} while (0)
460
461#define TAILQ_REMOVE(head, elm, field) do { \
462 if (((elm)->field.tqe_next) != NULL) \
463 (elm)->field.tqe_next->field.tqe_prev = \
464 (elm)->field.tqe_prev; \
465 else \
466 (head)->tqh_last = (elm)->field.tqe_prev; \
467 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \
468} while (0)
469
470#define TAILQ_REPLACE(head, elm, elm2, field) do { \
471 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \
472 (elm2)->field.tqe_next->field.tqe_prev = \
473 &(elm2)->field.tqe_next; \
474 else \
475 (head)->tqh_last = &(elm2)->field.tqe_next; \
476 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \
477 *(elm2)->field.tqe_prev = (elm2); \
478} while (0)
479
480/*
481 * Circular queue definitions.
482 */
483#define CIRCLEQ_HEAD(name, type) \
484struct name { \
485 struct type *cqh_first; /* first element */ \
486 struct type *cqh_last; /* last element */ \
487}
488
489#define CIRCLEQ_HEAD_INITIALIZER(head) \
490 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) }
491
492#define CIRCLEQ_ENTRY(type) \
493struct { \
494 struct type *cqe_next; /* next element */ \
495 struct type *cqe_prev; /* previous element */ \
496}
497
498/*
499 * Circular queue access methods
500 */
501#define CIRCLEQ_FIRST(head) ((head)->cqh_first)
502#define CIRCLEQ_LAST(head) ((head)->cqh_last)
503#define CIRCLEQ_END(head) ((void *)(head))
504#define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next)
505#define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev)
506#define CIRCLEQ_EMPTY(head) \
507 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head))
508
509#define CIRCLEQ_FOREACH(var, head, field) \
510 for((var) = CIRCLEQ_FIRST(head); \
511 (var) != CIRCLEQ_END(head); \
512 (var) = CIRCLEQ_NEXT(var, field))
513
514#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \
515 for((var) = CIRCLEQ_LAST(head); \
516 (var) != CIRCLEQ_END(head); \
517 (var) = CIRCLEQ_PREV(var, field))
518
519/*
520 * Circular queue functions.
521 */
522#define CIRCLEQ_INIT(head) do { \
523 (head)->cqh_first = CIRCLEQ_END(head); \
524 (head)->cqh_last = CIRCLEQ_END(head); \
525} while (0)
526
527#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \
528 (elm)->field.cqe_next = (listelm)->field.cqe_next; \
529 (elm)->field.cqe_prev = (listelm); \
530 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \
531 (head)->cqh_last = (elm); \
532 else \
533 (listelm)->field.cqe_next->field.cqe_prev = (elm); \
534 (listelm)->field.cqe_next = (elm); \
535} while (0)
536
537#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \
538 (elm)->field.cqe_next = (listelm); \
539 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \
540 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \
541 (head)->cqh_first = (elm); \
542 else \
543 (listelm)->field.cqe_prev->field.cqe_next = (elm); \
544 (listelm)->field.cqe_prev = (elm); \
545} while (0)
546
547#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \
548 (elm)->field.cqe_next = (head)->cqh_first; \
549 (elm)->field.cqe_prev = CIRCLEQ_END(head); \
550 if ((head)->cqh_last == CIRCLEQ_END(head)) \
551 (head)->cqh_last = (elm); \
552 else \
553 (head)->cqh_first->field.cqe_prev = (elm); \
554 (head)->cqh_first = (elm); \
555} while (0)
556
557#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \
558 (elm)->field.cqe_next = CIRCLEQ_END(head); \
559 (elm)->field.cqe_prev = (head)->cqh_last; \
560 if ((head)->cqh_first == CIRCLEQ_END(head)) \
561 (head)->cqh_first = (elm); \
562 else \
563 (head)->cqh_last->field.cqe_next = (elm); \
564 (head)->cqh_last = (elm); \
565} while (0)
566
567#define CIRCLEQ_REMOVE(head, elm, field) do { \
568 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \
569 (head)->cqh_last = (elm)->field.cqe_prev; \
570 else \
571 (elm)->field.cqe_next->field.cqe_prev = \
572 (elm)->field.cqe_prev; \
573 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \
574 (head)->cqh_first = (elm)->field.cqe_next; \
575 else \
576 (elm)->field.cqe_prev->field.cqe_next = \
577 (elm)->field.cqe_next; \
578} while (0)
579
580#define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \
581 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \
582 CIRCLEQ_END(head)) \
583 (head).cqh_last = (elm2); \
584 else \
585 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \
586 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \
587 CIRCLEQ_END(head)) \
588 (head).cqh_first = (elm2); \
589 else \
590 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \
591} while (0)
592
593#endif /* !_FAKE_QUEUE_H_ */