queue.h revision 204106
1/*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)queue.h 8.5 (Berkeley) 8/20/94 30 * $FreeBSD: head/sys/sys/queue.h 204106 2010-02-20 01:05:30Z emaste $ 31 */ 32 33#ifndef _SYS_QUEUE_H_ 34#define _SYS_QUEUE_H_ 35 36#include <sys/cdefs.h> 37 38/* 39 * This file defines four types of data structures: singly-linked lists, 40 * singly-linked tail queues, lists and tail queues. 41 * 42 * A singly-linked list is headed by a single forward pointer. The elements 43 * are singly linked for minimum space and pointer manipulation overhead at 44 * the expense of O(n) removal for arbitrary elements. New elements can be 45 * added to the list after an existing element or at the head of the list. 46 * Elements being removed from the head of the list should use the explicit 47 * macro for this purpose for optimum efficiency. A singly-linked list may 48 * only be traversed in the forward direction. Singly-linked lists are ideal 49 * for applications with large datasets and few or no removals or for 50 * implementing a LIFO queue. 51 * 52 * A singly-linked tail queue is headed by a pair of pointers, one to the 53 * head of the list and the other to the tail of the list. The elements are 54 * singly linked for minimum space and pointer manipulation overhead at the 55 * expense of O(n) removal for arbitrary elements. New elements can be added 56 * to the list after an existing element, at the head of the list, or at the 57 * end of the list. Elements being removed from the head of the tail queue 58 * should use the explicit macro for this purpose for optimum efficiency. 59 * A singly-linked tail queue may only be traversed in the forward direction. 60 * Singly-linked tail queues are ideal for applications with large datasets 61 * and few or no removals or for implementing a FIFO queue. 62 * 63 * A list is headed by a single forward pointer (or an array of forward 64 * pointers for a hash table header). The elements are doubly linked 65 * so that an arbitrary element can be removed without a need to 66 * traverse the list. New elements can be added to the list before 67 * or after an existing element or at the head of the list. A list 68 * may only be traversed in the forward direction. 69 * 70 * A tail queue is headed by a pair of pointers, one to the head of the 71 * list and the other to the tail of the list. The elements are doubly 72 * linked so that an arbitrary element can be removed without a need to 73 * traverse the list. New elements can be added to the list before or 74 * after an existing element, at the head of the list, or at the end of 75 * the list. A tail queue may be traversed in either direction. 76 * 77 * For details on the use of these macros, see the queue(3) manual page. 78 * 79 * 80 * SLIST LIST STAILQ TAILQ 81 * _HEAD + + + + 82 * _HEAD_INITIALIZER + + + + 83 * _ENTRY + + + + 84 * _INIT + + + + 85 * _EMPTY + + + + 86 * _FIRST + + + + 87 * _NEXT + + + + 88 * _PREV - - - + 89 * _LAST - - + + 90 * _FOREACH + + + + 91 * _FOREACH_SAFE + + + + 92 * _FOREACH_REVERSE - - - + 93 * _FOREACH_REVERSE_SAFE - - - + 94 * _INSERT_HEAD + + + + 95 * _INSERT_BEFORE - + - + 96 * _INSERT_AFTER + + + + 97 * _INSERT_TAIL - - + + 98 * _CONCAT - - + + 99 * _REMOVE_AFTER + - + - 100 * _REMOVE_HEAD + - + - 101 * _REMOVE + + + + 102 * 103 */ 104#ifdef QUEUE_MACRO_DEBUG 105/* Store the last 2 places the queue element or head was altered */ 106struct qm_trace { 107 char * lastfile; 108 int lastline; 109 char * prevfile; 110 int prevline; 111}; 112 113#define TRACEBUF struct qm_trace trace; 114#define TRASHIT(x) do {(x) = (void *)-1;} while (0) 115#define QMD_SAVELINK(name, link) void **name = (void *)&(link) 116 117#define QMD_TRACE_HEAD(head) do { \ 118 (head)->trace.prevline = (head)->trace.lastline; \ 119 (head)->trace.prevfile = (head)->trace.lastfile; \ 120 (head)->trace.lastline = __LINE__; \ 121 (head)->trace.lastfile = __FILE__; \ 122} while (0) 123 124#define QMD_TRACE_ELEM(elem) do { \ 125 (elem)->trace.prevline = (elem)->trace.lastline; \ 126 (elem)->trace.prevfile = (elem)->trace.lastfile; \ 127 (elem)->trace.lastline = __LINE__; \ 128 (elem)->trace.lastfile = __FILE__; \ 129} while (0) 130 131#else 132#define QMD_TRACE_ELEM(elem) 133#define QMD_TRACE_HEAD(head) 134#define QMD_SAVELINK(name, link) 135#define TRACEBUF 136#define TRASHIT(x) 137#endif /* QUEUE_MACRO_DEBUG */ 138 139/* 140 * Singly-linked List declarations. 141 */ 142#define SLIST_HEAD(name, type) \ 143struct name { \ 144 struct type *slh_first; /* first element */ \ 145} 146 147#define SLIST_HEAD_INITIALIZER(head) \ 148 { NULL } 149 150#define SLIST_ENTRY(type) \ 151struct { \ 152 struct type *sle_next; /* next element */ \ 153} 154 155/* 156 * Singly-linked List functions. 157 */ 158#define SLIST_EMPTY(head) ((head)->slh_first == NULL) 159 160#define SLIST_FIRST(head) ((head)->slh_first) 161 162#define SLIST_FOREACH(var, head, field) \ 163 for ((var) = SLIST_FIRST((head)); \ 164 (var); \ 165 (var) = SLIST_NEXT((var), field)) 166 167#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 168 for ((var) = SLIST_FIRST((head)); \ 169 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 170 (var) = (tvar)) 171 172#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 173 for ((varp) = &SLIST_FIRST((head)); \ 174 ((var) = *(varp)) != NULL; \ 175 (varp) = &SLIST_NEXT((var), field)) 176 177#define SLIST_INIT(head) do { \ 178 SLIST_FIRST((head)) = NULL; \ 179} while (0) 180 181#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 182 SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 183 SLIST_NEXT((slistelm), field) = (elm); \ 184} while (0) 185 186#define SLIST_INSERT_HEAD(head, elm, field) do { \ 187 SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 188 SLIST_FIRST((head)) = (elm); \ 189} while (0) 190 191#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 192 193#define SLIST_REMOVE(head, elm, type, field) do { \ 194 QMD_SAVELINK(oldnext, (elm)->field.sle_next); \ 195 if (SLIST_FIRST((head)) == (elm)) { \ 196 SLIST_REMOVE_HEAD((head), field); \ 197 } \ 198 else { \ 199 struct type *curelm = SLIST_FIRST((head)); \ 200 while (SLIST_NEXT(curelm, field) != (elm)) \ 201 curelm = SLIST_NEXT(curelm, field); \ 202 SLIST_REMOVE_AFTER(curelm, field); \ 203 } \ 204 TRASHIT(*oldnext); \ 205} while (0) 206 207#define SLIST_REMOVE_AFTER(elm, field) do { \ 208 SLIST_NEXT(elm, field) = \ 209 SLIST_NEXT(SLIST_NEXT(elm, field), field); \ 210} while (0) 211 212#define SLIST_REMOVE_HEAD(head, field) do { \ 213 SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 214} while (0) 215 216/* 217 * Singly-linked Tail queue declarations. 218 */ 219#define STAILQ_HEAD(name, type) \ 220struct name { \ 221 struct type *stqh_first;/* first element */ \ 222 struct type **stqh_last;/* addr of last next element */ \ 223} 224 225#define STAILQ_HEAD_INITIALIZER(head) \ 226 { NULL, &(head).stqh_first } 227 228#define STAILQ_ENTRY(type) \ 229struct { \ 230 struct type *stqe_next; /* next element */ \ 231} 232 233/* 234 * Singly-linked Tail queue functions. 235 */ 236#define STAILQ_CONCAT(head1, head2) do { \ 237 if (!STAILQ_EMPTY((head2))) { \ 238 *(head1)->stqh_last = (head2)->stqh_first; \ 239 (head1)->stqh_last = (head2)->stqh_last; \ 240 STAILQ_INIT((head2)); \ 241 } \ 242} while (0) 243 244#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL) 245 246#define STAILQ_FIRST(head) ((head)->stqh_first) 247 248#define STAILQ_FOREACH(var, head, field) \ 249 for((var) = STAILQ_FIRST((head)); \ 250 (var); \ 251 (var) = STAILQ_NEXT((var), field)) 252 253 254#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 255 for ((var) = STAILQ_FIRST((head)); \ 256 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 257 (var) = (tvar)) 258 259#define STAILQ_INIT(head) do { \ 260 STAILQ_FIRST((head)) = NULL; \ 261 (head)->stqh_last = &STAILQ_FIRST((head)); \ 262} while (0) 263 264#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 265 if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 266 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 267 STAILQ_NEXT((tqelm), field) = (elm); \ 268} while (0) 269 270#define STAILQ_INSERT_HEAD(head, elm, field) do { \ 271 if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 272 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 273 STAILQ_FIRST((head)) = (elm); \ 274} while (0) 275 276#define STAILQ_INSERT_TAIL(head, elm, field) do { \ 277 STAILQ_NEXT((elm), field) = NULL; \ 278 *(head)->stqh_last = (elm); \ 279 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 280} while (0) 281 282#define STAILQ_LAST(head, type, field) \ 283 (STAILQ_EMPTY((head)) ? \ 284 NULL : \ 285 ((struct type *)(void *) \ 286 ((char *)((head)->stqh_last) - __offsetof(struct type, field)))) 287 288#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 289 290#define STAILQ_REMOVE(head, elm, type, field) do { \ 291 QMD_SAVELINK(oldnext, (elm)->field.stqe_next); \ 292 if (STAILQ_FIRST((head)) == (elm)) { \ 293 STAILQ_REMOVE_HEAD((head), field); \ 294 } \ 295 else { \ 296 struct type *curelm = STAILQ_FIRST((head)); \ 297 while (STAILQ_NEXT(curelm, field) != (elm)) \ 298 curelm = STAILQ_NEXT(curelm, field); \ 299 STAILQ_REMOVE_AFTER(head, curelm, field); \ 300 } \ 301 TRASHIT(*oldnext); \ 302} while (0) 303 304#define STAILQ_REMOVE_HEAD(head, field) do { \ 305 if ((STAILQ_FIRST((head)) = \ 306 STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 307 (head)->stqh_last = &STAILQ_FIRST((head)); \ 308} while (0) 309 310#define STAILQ_REMOVE_AFTER(head, elm, field) do { \ 311 if ((STAILQ_NEXT(elm, field) = \ 312 STAILQ_NEXT(STAILQ_NEXT(elm, field), field)) == NULL) \ 313 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 314} while (0) 315 316#define STAILQ_SWAP(head1, head2, type) do { \ 317 struct type *swap_first = STAILQ_FIRST(head1); \ 318 struct type **swap_last = (head1)->stqh_last; \ 319 STAILQ_FIRST(head1) = STAILQ_FIRST(head2); \ 320 (head1)->stqh_last = (head2)->stqh_last; \ 321 STAILQ_FIRST(head2) = swap_first; \ 322 (head2)->stqh_last = swap_last; \ 323 if (STAILQ_EMPTY(head1)) \ 324 (head1)->stqh_last = &STAILQ_FIRST(head1); \ 325 if (STAILQ_EMPTY(head2)) \ 326 (head2)->stqh_last = &STAILQ_FIRST(head2); \ 327} while (0) 328 329 330/* 331 * List declarations. 332 */ 333#define LIST_HEAD(name, type) \ 334struct name { \ 335 struct type *lh_first; /* first element */ \ 336} 337 338#define LIST_HEAD_INITIALIZER(head) \ 339 { NULL } 340 341#define LIST_ENTRY(type) \ 342struct { \ 343 struct type *le_next; /* next element */ \ 344 struct type **le_prev; /* address of previous next element */ \ 345} 346 347/* 348 * List functions. 349 */ 350 351#if (defined(_KERNEL) && defined(INVARIANTS)) 352#define QMD_LIST_CHECK_HEAD(head, field) do { \ 353 if (LIST_FIRST((head)) != NULL && \ 354 LIST_FIRST((head))->field.le_prev != \ 355 &LIST_FIRST((head))) \ 356 panic("Bad list head %p first->prev != head", (head)); \ 357} while (0) 358 359#define QMD_LIST_CHECK_NEXT(elm, field) do { \ 360 if (LIST_NEXT((elm), field) != NULL && \ 361 LIST_NEXT((elm), field)->field.le_prev != \ 362 &((elm)->field.le_next)) \ 363 panic("Bad link elm %p next->prev != elm", (elm)); \ 364} while (0) 365 366#define QMD_LIST_CHECK_PREV(elm, field) do { \ 367 if (*(elm)->field.le_prev != (elm)) \ 368 panic("Bad link elm %p prev->next != elm", (elm)); \ 369} while (0) 370#else 371#define QMD_LIST_CHECK_HEAD(head, field) 372#define QMD_LIST_CHECK_NEXT(elm, field) 373#define QMD_LIST_CHECK_PREV(elm, field) 374#endif /* (_KERNEL && INVARIANTS) */ 375 376#define LIST_EMPTY(head) ((head)->lh_first == NULL) 377 378#define LIST_FIRST(head) ((head)->lh_first) 379 380#define LIST_FOREACH(var, head, field) \ 381 for ((var) = LIST_FIRST((head)); \ 382 (var); \ 383 (var) = LIST_NEXT((var), field)) 384 385#define LIST_FOREACH_SAFE(var, head, field, tvar) \ 386 for ((var) = LIST_FIRST((head)); \ 387 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 388 (var) = (tvar)) 389 390#define LIST_INIT(head) do { \ 391 LIST_FIRST((head)) = NULL; \ 392} while (0) 393 394#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 395 QMD_LIST_CHECK_NEXT(listelm, field); \ 396 if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 397 LIST_NEXT((listelm), field)->field.le_prev = \ 398 &LIST_NEXT((elm), field); \ 399 LIST_NEXT((listelm), field) = (elm); \ 400 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 401} while (0) 402 403#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 404 QMD_LIST_CHECK_PREV(listelm, field); \ 405 (elm)->field.le_prev = (listelm)->field.le_prev; \ 406 LIST_NEXT((elm), field) = (listelm); \ 407 *(listelm)->field.le_prev = (elm); \ 408 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 409} while (0) 410 411#define LIST_INSERT_HEAD(head, elm, field) do { \ 412 QMD_LIST_CHECK_HEAD((head), field); \ 413 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 414 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 415 LIST_FIRST((head)) = (elm); \ 416 (elm)->field.le_prev = &LIST_FIRST((head)); \ 417} while (0) 418 419#define LIST_NEXT(elm, field) ((elm)->field.le_next) 420 421#define LIST_REMOVE(elm, field) do { \ 422 QMD_SAVELINK(oldnext, (elm)->field.le_next); \ 423 QMD_SAVELINK(oldprev, (elm)->field.le_prev); \ 424 QMD_LIST_CHECK_NEXT(elm, field); \ 425 QMD_LIST_CHECK_PREV(elm, field); \ 426 if (LIST_NEXT((elm), field) != NULL) \ 427 LIST_NEXT((elm), field)->field.le_prev = \ 428 (elm)->field.le_prev; \ 429 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 430 TRASHIT(*oldnext); \ 431 TRASHIT(*oldprev); \ 432} while (0) 433 434#define LIST_SWAP(head1, head2, type, field) do { \ 435 struct type *swap_tmp = LIST_FIRST((head1)); \ 436 LIST_FIRST((head1)) = LIST_FIRST((head2)); \ 437 LIST_FIRST((head2)) = swap_tmp; \ 438 if ((swap_tmp = LIST_FIRST((head1))) != NULL) \ 439 swap_tmp->field.le_prev = &LIST_FIRST((head1)); \ 440 if ((swap_tmp = LIST_FIRST((head2))) != NULL) \ 441 swap_tmp->field.le_prev = &LIST_FIRST((head2)); \ 442} while (0) 443 444/* 445 * Tail queue declarations. 446 */ 447#define TAILQ_HEAD(name, type) \ 448struct name { \ 449 struct type *tqh_first; /* first element */ \ 450 struct type **tqh_last; /* addr of last next element */ \ 451 TRACEBUF \ 452} 453 454#define TAILQ_HEAD_INITIALIZER(head) \ 455 { NULL, &(head).tqh_first } 456 457#define TAILQ_ENTRY(type) \ 458struct { \ 459 struct type *tqe_next; /* next element */ \ 460 struct type **tqe_prev; /* address of previous next element */ \ 461 TRACEBUF \ 462} 463 464/* 465 * Tail queue functions. 466 */ 467#if (defined(_KERNEL) && defined(INVARIANTS)) 468#define QMD_TAILQ_CHECK_HEAD(head, field) do { \ 469 if (!TAILQ_EMPTY(head) && \ 470 TAILQ_FIRST((head))->field.tqe_prev != \ 471 &TAILQ_FIRST((head))) \ 472 panic("Bad tailq head %p first->prev != head", (head)); \ 473} while (0) 474 475#define QMD_TAILQ_CHECK_TAIL(head, field) do { \ 476 if (*(head)->tqh_last != NULL) \ 477 panic("Bad tailq NEXT(%p->tqh_last) != NULL", (head)); \ 478} while (0) 479 480#define QMD_TAILQ_CHECK_NEXT(elm, field) do { \ 481 if (TAILQ_NEXT((elm), field) != NULL && \ 482 TAILQ_NEXT((elm), field)->field.tqe_prev != \ 483 &((elm)->field.tqe_next)) \ 484 panic("Bad link elm %p next->prev != elm", (elm)); \ 485} while (0) 486 487#define QMD_TAILQ_CHECK_PREV(elm, field) do { \ 488 if (*(elm)->field.tqe_prev != (elm)) \ 489 panic("Bad link elm %p prev->next != elm", (elm)); \ 490} while (0) 491#else 492#define QMD_TAILQ_CHECK_HEAD(head, field) 493#define QMD_TAILQ_CHECK_TAIL(head, headname) 494#define QMD_TAILQ_CHECK_NEXT(elm, field) 495#define QMD_TAILQ_CHECK_PREV(elm, field) 496#endif /* (_KERNEL && INVARIANTS) */ 497 498#define TAILQ_CONCAT(head1, head2, field) do { \ 499 if (!TAILQ_EMPTY(head2)) { \ 500 *(head1)->tqh_last = (head2)->tqh_first; \ 501 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 502 (head1)->tqh_last = (head2)->tqh_last; \ 503 TAILQ_INIT((head2)); \ 504 QMD_TRACE_HEAD(head1); \ 505 QMD_TRACE_HEAD(head2); \ 506 } \ 507} while (0) 508 509#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 510 511#define TAILQ_FIRST(head) ((head)->tqh_first) 512 513#define TAILQ_FOREACH(var, head, field) \ 514 for ((var) = TAILQ_FIRST((head)); \ 515 (var); \ 516 (var) = TAILQ_NEXT((var), field)) 517 518#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 519 for ((var) = TAILQ_FIRST((head)); \ 520 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 521 (var) = (tvar)) 522 523#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 524 for ((var) = TAILQ_LAST((head), headname); \ 525 (var); \ 526 (var) = TAILQ_PREV((var), headname, field)) 527 528#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 529 for ((var) = TAILQ_LAST((head), headname); \ 530 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 531 (var) = (tvar)) 532 533#define TAILQ_INIT(head) do { \ 534 TAILQ_FIRST((head)) = NULL; \ 535 (head)->tqh_last = &TAILQ_FIRST((head)); \ 536 QMD_TRACE_HEAD(head); \ 537} while (0) 538 539#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 540 QMD_TAILQ_CHECK_NEXT(listelm, field); \ 541 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 542 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 543 &TAILQ_NEXT((elm), field); \ 544 else { \ 545 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 546 QMD_TRACE_HEAD(head); \ 547 } \ 548 TAILQ_NEXT((listelm), field) = (elm); \ 549 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 550 QMD_TRACE_ELEM(&(elm)->field); \ 551 QMD_TRACE_ELEM(&listelm->field); \ 552} while (0) 553 554#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 555 QMD_TAILQ_CHECK_PREV(listelm, field); \ 556 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 557 TAILQ_NEXT((elm), field) = (listelm); \ 558 *(listelm)->field.tqe_prev = (elm); \ 559 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 560 QMD_TRACE_ELEM(&(elm)->field); \ 561 QMD_TRACE_ELEM(&listelm->field); \ 562} while (0) 563 564#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 565 QMD_TAILQ_CHECK_HEAD(head, field); \ 566 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 567 TAILQ_FIRST((head))->field.tqe_prev = \ 568 &TAILQ_NEXT((elm), field); \ 569 else \ 570 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 571 TAILQ_FIRST((head)) = (elm); \ 572 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 573 QMD_TRACE_HEAD(head); \ 574 QMD_TRACE_ELEM(&(elm)->field); \ 575} while (0) 576 577#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 578 QMD_TAILQ_CHECK_TAIL(head, field); \ 579 TAILQ_NEXT((elm), field) = NULL; \ 580 (elm)->field.tqe_prev = (head)->tqh_last; \ 581 *(head)->tqh_last = (elm); \ 582 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 583 QMD_TRACE_HEAD(head); \ 584 QMD_TRACE_ELEM(&(elm)->field); \ 585} while (0) 586 587#define TAILQ_LAST(head, headname) \ 588 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 589 590#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 591 592#define TAILQ_PREV(elm, headname, field) \ 593 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 594 595#define TAILQ_REMOVE(head, elm, field) do { \ 596 QMD_SAVELINK(oldnext, (elm)->field.tqe_next); \ 597 QMD_SAVELINK(oldprev, (elm)->field.tqe_prev); \ 598 QMD_TAILQ_CHECK_NEXT(elm, field); \ 599 QMD_TAILQ_CHECK_PREV(elm, field); \ 600 if ((TAILQ_NEXT((elm), field)) != NULL) \ 601 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 602 (elm)->field.tqe_prev; \ 603 else { \ 604 (head)->tqh_last = (elm)->field.tqe_prev; \ 605 QMD_TRACE_HEAD(head); \ 606 } \ 607 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 608 TRASHIT(*oldnext); \ 609 TRASHIT(*oldprev); \ 610 QMD_TRACE_ELEM(&(elm)->field); \ 611} while (0) 612 613#define TAILQ_SWAP(head1, head2, type, field) do { \ 614 struct type *swap_first = (head1)->tqh_first; \ 615 struct type **swap_last = (head1)->tqh_last; \ 616 (head1)->tqh_first = (head2)->tqh_first; \ 617 (head1)->tqh_last = (head2)->tqh_last; \ 618 (head2)->tqh_first = swap_first; \ 619 (head2)->tqh_last = swap_last; \ 620 if ((swap_first = (head1)->tqh_first) != NULL) \ 621 swap_first->field.tqe_prev = &(head1)->tqh_first; \ 622 else \ 623 (head1)->tqh_last = &(head1)->tqh_first; \ 624 if ((swap_first = (head2)->tqh_first) != NULL) \ 625 swap_first->field.tqe_prev = &(head2)->tqh_first; \ 626 else \ 627 (head2)->tqh_last = &(head2)->tqh_first; \ 628} while (0) 629 630#endif /* !_SYS_QUEUE_H_ */ 631