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: src/sys/sys/queue.h,v 1.68 2006/10/24 11:20:29 ru Exp $ 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_HEAD + - + - 100 * _REMOVE + + + + 101 * 102 */ 103#ifdef QUEUE_MACRO_DEBUG 104/* Store the last 2 places the queue element or head was altered */ 105struct qm_trace { 106 char * lastfile; 107 int lastline; 108 char * prevfile; 109 int prevline; 110}; 111 112#define TRACEBUF struct qm_trace trace; 113#define TRASHIT(x) do {(x) = (void *)-1;} while (0) 114 115#define QMD_TRACE_HEAD(head) do { \ 116 (head)->trace.prevline = (head)->trace.lastline; \ 117 (head)->trace.prevfile = (head)->trace.lastfile; \ 118 (head)->trace.lastline = __LINE__; \ 119 (head)->trace.lastfile = __FILE__; \ 120} while (0) 121 122#define QMD_TRACE_ELEM(elem) do { \ 123 (elem)->trace.prevline = (elem)->trace.lastline; \ 124 (elem)->trace.prevfile = (elem)->trace.lastfile; \ 125 (elem)->trace.lastline = __LINE__; \ 126 (elem)->trace.lastfile = __FILE__; \ 127} while (0) 128 129#else 130#define QMD_TRACE_ELEM(elem) 131#define QMD_TRACE_HEAD(head) 132#define TRACEBUF 133#define TRASHIT(x) 134#endif /* QUEUE_MACRO_DEBUG */ 135 136/* 137 * Singly-linked List declarations. 138 */ 139#define SLIST_HEAD(name, type) \ 140struct name { \ 141 struct type *slh_first; /* first element */ \ 142} 143 144#define SLIST_HEAD_INITIALIZER(head) \ 145 { NULL } 146 147#define SLIST_ENTRY(type) \ 148struct { \ 149 struct type *sle_next; /* next element */ \ 150} 151 152/* 153 * Singly-linked List functions. 154 */ 155#define SLIST_EMPTY(head) ((head)->slh_first == NULL) 156 157#define SLIST_FIRST(head) ((head)->slh_first) 158 159#define SLIST_FOREACH(var, head, field) \ 160 for ((var) = SLIST_FIRST((head)); \ 161 (var); \ 162 (var) = SLIST_NEXT((var), field)) 163 164#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 165 for ((var) = SLIST_FIRST((head)); \ 166 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 167 (var) = (tvar)) 168 169#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 170 for ((varp) = &SLIST_FIRST((head)); \ 171 ((var) = *(varp)) != NULL; \ 172 (varp) = &SLIST_NEXT((var), field)) 173 174#define SLIST_INIT(head) do { \ 175 SLIST_FIRST((head)) = NULL; \ 176} while (0) 177 178#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 179 SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 180 SLIST_NEXT((slistelm), field) = (elm); \ 181} while (0) 182 183#define SLIST_INSERT_HEAD(head, elm, field) do { \ 184 SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 185 SLIST_FIRST((head)) = (elm); \ 186} while (0) 187 188#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 189 190#define SLIST_REMOVE(head, elm, type, field) do { \ 191 if (SLIST_FIRST((head)) == (elm)) { \ 192 SLIST_REMOVE_HEAD((head), field); \ 193 } \ 194 else { \ 195 struct type *curelm = SLIST_FIRST((head)); \ 196 while (SLIST_NEXT(curelm, field) != (elm)) \ 197 curelm = SLIST_NEXT(curelm, field); \ 198 SLIST_NEXT(curelm, field) = \ 199 SLIST_NEXT(SLIST_NEXT(curelm, field), field); \ 200 } \ 201 TRASHIT((elm)->field.sle_next); \ 202} while (0) 203 204#define SLIST_REMOVE_HEAD(head, field) do { \ 205 SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 206} while (0) 207 208/* 209 * Singly-linked Tail queue declarations. 210 */ 211#define STAILQ_HEAD(name, type) \ 212struct name { \ 213 struct type *stqh_first;/* first element */ \ 214 struct type **stqh_last;/* addr of last next element */ \ 215} 216 217#define STAILQ_HEAD_INITIALIZER(head) \ 218 { NULL, &(head).stqh_first } 219 220#define STAILQ_ENTRY(type) \ 221struct { \ 222 struct type *stqe_next; /* next element */ \ 223} 224 225/* 226 * Singly-linked Tail queue functions. 227 */ 228#define STAILQ_CONCAT(head1, head2) do { \ 229 if (!STAILQ_EMPTY((head2))) { \ 230 *(head1)->stqh_last = (head2)->stqh_first; \ 231 (head1)->stqh_last = (head2)->stqh_last; \ 232 STAILQ_INIT((head2)); \ 233 } \ 234} while (0) 235 236#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL) 237 238#define STAILQ_FIRST(head) ((head)->stqh_first) 239 240#define STAILQ_FOREACH(var, head, field) \ 241 for((var) = STAILQ_FIRST((head)); \ 242 (var); \ 243 (var) = STAILQ_NEXT((var), field)) 244 245 246#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 247 for ((var) = STAILQ_FIRST((head)); \ 248 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 249 (var) = (tvar)) 250 251#define STAILQ_INIT(head) do { \ 252 STAILQ_FIRST((head)) = NULL; \ 253 (head)->stqh_last = &STAILQ_FIRST((head)); \ 254} while (0) 255 256#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 257 if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 258 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 259 STAILQ_NEXT((tqelm), field) = (elm); \ 260} while (0) 261 262#define STAILQ_INSERT_HEAD(head, elm, field) do { \ 263 if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 264 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 265 STAILQ_FIRST((head)) = (elm); \ 266} while (0) 267 268#define STAILQ_INSERT_TAIL(head, elm, field) do { \ 269 STAILQ_NEXT((elm), field) = NULL; \ 270 *(head)->stqh_last = (elm); \ 271 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 272} while (0) 273 274#define STAILQ_LAST(head, type, field) \ 275 (STAILQ_EMPTY((head)) ? \ 276 NULL : \ 277 ((struct type *)(void *) \ 278 ((char *)((head)->stqh_last) - __offsetof(struct type, field)))) 279 280#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 281 282#define STAILQ_REMOVE(head, elm, type, field) do { \ 283 if (STAILQ_FIRST((head)) == (elm)) { \ 284 STAILQ_REMOVE_HEAD((head), field); \ 285 } \ 286 else { \ 287 struct type *curelm = STAILQ_FIRST((head)); \ 288 while (STAILQ_NEXT(curelm, field) != (elm)) \ 289 curelm = STAILQ_NEXT(curelm, field); \ 290 if ((STAILQ_NEXT(curelm, field) = \ 291 STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\ 292 (head)->stqh_last = &STAILQ_NEXT((curelm), field);\ 293 } \ 294 TRASHIT((elm)->field.stqe_next); \ 295} while (0) 296 297#define STAILQ_REMOVE_HEAD(head, field) do { \ 298 if ((STAILQ_FIRST((head)) = \ 299 STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 300 (head)->stqh_last = &STAILQ_FIRST((head)); \ 301} while (0) 302 303/* 304 * List declarations. 305 */ 306#define LIST_HEAD(name, type) \ 307struct name { \ 308 struct type *lh_first; /* first element */ \ 309} 310 311#define LIST_HEAD_INITIALIZER(head) \ 312 { NULL } 313 314#define LIST_ENTRY(type) \ 315struct { \ 316 struct type *le_next; /* next element */ \ 317 struct type **le_prev; /* address of previous next element */ \ 318} 319 320/* 321 * List functions. 322 */ 323 324#if (defined(_KERNEL) && defined(INVARIANTS)) 325#define QMD_LIST_CHECK_HEAD(head, field) do { \ 326 if (LIST_FIRST((head)) != NULL && \ 327 LIST_FIRST((head))->field.le_prev != \ 328 &LIST_FIRST((head))) \ 329 panic("Bad list head %p first->prev != head", (head)); \ 330} while (0) 331 332#define QMD_LIST_CHECK_NEXT(elm, field) do { \ 333 if (LIST_NEXT((elm), field) != NULL && \ 334 LIST_NEXT((elm), field)->field.le_prev != \ 335 &((elm)->field.le_next)) \ 336 panic("Bad link elm %p next->prev != elm", (elm)); \ 337} while (0) 338 339#define QMD_LIST_CHECK_PREV(elm, field) do { \ 340 if (*(elm)->field.le_prev != (elm)) \ 341 panic("Bad link elm %p prev->next != elm", (elm)); \ 342} while (0) 343#else 344#define QMD_LIST_CHECK_HEAD(head, field) 345#define QMD_LIST_CHECK_NEXT(elm, field) 346#define QMD_LIST_CHECK_PREV(elm, field) 347#endif /* (_KERNEL && INVARIANTS) */ 348 349#define LIST_EMPTY(head) ((head)->lh_first == NULL) 350 351#define LIST_FIRST(head) ((head)->lh_first) 352 353#define LIST_FOREACH(var, head, field) \ 354 for ((var) = LIST_FIRST((head)); \ 355 (var); \ 356 (var) = LIST_NEXT((var), field)) 357 358#define LIST_FOREACH_SAFE(var, head, field, tvar) \ 359 for ((var) = LIST_FIRST((head)); \ 360 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 361 (var) = (tvar)) 362 363#define LIST_INIT(head) do { \ 364 LIST_FIRST((head)) = NULL; \ 365} while (0) 366 367#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 368 QMD_LIST_CHECK_NEXT(listelm, field); \ 369 if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 370 LIST_NEXT((listelm), field)->field.le_prev = \ 371 &LIST_NEXT((elm), field); \ 372 LIST_NEXT((listelm), field) = (elm); \ 373 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 374} while (0) 375 376#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 377 QMD_LIST_CHECK_PREV(listelm, field); \ 378 (elm)->field.le_prev = (listelm)->field.le_prev; \ 379 LIST_NEXT((elm), field) = (listelm); \ 380 *(listelm)->field.le_prev = (elm); \ 381 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 382} while (0) 383 384#define LIST_INSERT_HEAD(head, elm, field) do { \ 385 QMD_LIST_CHECK_HEAD((head), field); \ 386 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 387 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 388 LIST_FIRST((head)) = (elm); \ 389 (elm)->field.le_prev = &LIST_FIRST((head)); \ 390} while (0) 391 392#define LIST_NEXT(elm, field) ((elm)->field.le_next) 393 394#define LIST_REMOVE(elm, field) do { \ 395 QMD_LIST_CHECK_NEXT(elm, field); \ 396 QMD_LIST_CHECK_PREV(elm, field); \ 397 if (LIST_NEXT((elm), field) != NULL) \ 398 LIST_NEXT((elm), field)->field.le_prev = \ 399 (elm)->field.le_prev; \ 400 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 401 TRASHIT((elm)->field.le_next); \ 402 TRASHIT((elm)->field.le_prev); \ 403} while (0) 404 405/* 406 * Tail queue declarations. 407 */ 408#define TAILQ_HEAD(name, type) \ 409struct name { \ 410 struct type *tqh_first; /* first element */ \ 411 struct type **tqh_last; /* addr of last next element */ \ 412 TRACEBUF \ 413} 414 415#define TAILQ_HEAD_INITIALIZER(head) \ 416 { NULL, &(head).tqh_first } 417 418#define TAILQ_ENTRY(type) \ 419struct { \ 420 struct type *tqe_next; /* next element */ \ 421 struct type **tqe_prev; /* address of previous next element */ \ 422 TRACEBUF \ 423} 424 425/* 426 * Tail queue functions. 427 */ 428#if (defined(_KERNEL) && defined(INVARIANTS)) 429#define QMD_TAILQ_CHECK_HEAD(head, field) do { \ 430 if (!TAILQ_EMPTY(head) && \ 431 TAILQ_FIRST((head))->field.tqe_prev != \ 432 &TAILQ_FIRST((head))) \ 433 panic("Bad tailq head %p first->prev != head", (head)); \ 434} while (0) 435 436#define QMD_TAILQ_CHECK_TAIL(head, field) do { \ 437 if (*(head)->tqh_last != NULL) \ 438 panic("Bad tailq NEXT(%p->tqh_last) != NULL", (head)); \ 439} while (0) 440 441#define QMD_TAILQ_CHECK_NEXT(elm, field) do { \ 442 if (TAILQ_NEXT((elm), field) != NULL && \ 443 TAILQ_NEXT((elm), field)->field.tqe_prev != \ 444 &((elm)->field.tqe_next)) \ 445 panic("Bad link elm %p next->prev != elm", (elm)); \ 446} while (0) 447 448#define QMD_TAILQ_CHECK_PREV(elm, field) do { \ 449 if (*(elm)->field.tqe_prev != (elm)) \ 450 panic("Bad link elm %p prev->next != elm", (elm)); \ 451} while (0) 452#else 453#define QMD_TAILQ_CHECK_HEAD(head, field) 454#define QMD_TAILQ_CHECK_TAIL(head, headname) 455#define QMD_TAILQ_CHECK_NEXT(elm, field) 456#define QMD_TAILQ_CHECK_PREV(elm, field) 457#endif /* (_KERNEL && INVARIANTS) */ 458 459#define TAILQ_CONCAT(head1, head2, field) do { \ 460 if (!TAILQ_EMPTY(head2)) { \ 461 *(head1)->tqh_last = (head2)->tqh_first; \ 462 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 463 (head1)->tqh_last = (head2)->tqh_last; \ 464 TAILQ_INIT((head2)); \ 465 QMD_TRACE_HEAD(head1); \ 466 QMD_TRACE_HEAD(head2); \ 467 } \ 468} while (0) 469 470#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 471 472#define TAILQ_FIRST(head) ((head)->tqh_first) 473 474#define TAILQ_FOREACH(var, head, field) \ 475 for ((var) = TAILQ_FIRST((head)); \ 476 (var); \ 477 (var) = TAILQ_NEXT((var), field)) 478 479#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 480 for ((var) = TAILQ_FIRST((head)); \ 481 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 482 (var) = (tvar)) 483 484#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 485 for ((var) = TAILQ_LAST((head), headname); \ 486 (var); \ 487 (var) = TAILQ_PREV((var), headname, field)) 488 489#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 490 for ((var) = TAILQ_LAST((head), headname); \ 491 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 492 (var) = (tvar)) 493 494#define TAILQ_INIT(head) do { \ 495 TAILQ_FIRST((head)) = NULL; \ 496 (head)->tqh_last = &TAILQ_FIRST((head)); \ 497 QMD_TRACE_HEAD(head); \ 498} while (0) 499 500#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 501 QMD_TAILQ_CHECK_NEXT(listelm, field); \ 502 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 503 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 504 &TAILQ_NEXT((elm), field); \ 505 else { \ 506 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 507 QMD_TRACE_HEAD(head); \ 508 } \ 509 TAILQ_NEXT((listelm), field) = (elm); \ 510 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 511 QMD_TRACE_ELEM(&(elm)->field); \ 512 QMD_TRACE_ELEM(&listelm->field); \ 513} while (0) 514 515#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 516 QMD_TAILQ_CHECK_PREV(listelm, field); \ 517 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 518 TAILQ_NEXT((elm), field) = (listelm); \ 519 *(listelm)->field.tqe_prev = (elm); \ 520 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 521 QMD_TRACE_ELEM(&(elm)->field); \ 522 QMD_TRACE_ELEM(&listelm->field); \ 523} while (0) 524 525#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 526 QMD_TAILQ_CHECK_HEAD(head, field); \ 527 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 528 TAILQ_FIRST((head))->field.tqe_prev = \ 529 &TAILQ_NEXT((elm), field); \ 530 else \ 531 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 532 TAILQ_FIRST((head)) = (elm); \ 533 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 534 QMD_TRACE_HEAD(head); \ 535 QMD_TRACE_ELEM(&(elm)->field); \ 536} while (0) 537 538#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 539 QMD_TAILQ_CHECK_TAIL(head, field); \ 540 TAILQ_NEXT((elm), field) = NULL; \ 541 (elm)->field.tqe_prev = (head)->tqh_last; \ 542 *(head)->tqh_last = (elm); \ 543 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 544 QMD_TRACE_HEAD(head); \ 545 QMD_TRACE_ELEM(&(elm)->field); \ 546} while (0) 547 548#define TAILQ_LAST(head, headname) \ 549 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 550 551#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 552 553#define TAILQ_PREV(elm, headname, field) \ 554 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 555 556#define TAILQ_REMOVE(head, elm, field) do { \ 557 QMD_TAILQ_CHECK_NEXT(elm, field); \ 558 QMD_TAILQ_CHECK_PREV(elm, field); \ 559 if ((TAILQ_NEXT((elm), field)) != NULL) \ 560 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 561 (elm)->field.tqe_prev; \ 562 else { \ 563 (head)->tqh_last = (elm)->field.tqe_prev; \ 564 QMD_TRACE_HEAD(head); \ 565 } \ 566 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 567 TRASHIT((elm)->field.tqe_next); \ 568 TRASHIT((elm)->field.tqe_prev); \ 569 QMD_TRACE_ELEM(&(elm)->field); \ 570} while (0) 571 572 573#ifdef _KERNEL 574 575/* 576 * XXX insque() and remque() are an old way of handling certain queues. 577 * They bogusly assumes that all queue heads look alike. 578 */ 579 580struct quehead { 581 struct quehead *qh_link; 582 struct quehead *qh_rlink; 583}; 584 585#ifdef __CC_SUPPORTS___INLINE 586 587static __inline void 588insque(void *a, void *b) 589{ 590 struct quehead *element = (struct quehead *)a, 591 *head = (struct quehead *)b; 592 593 element->qh_link = head->qh_link; 594 element->qh_rlink = head; 595 head->qh_link = element; 596 element->qh_link->qh_rlink = element; 597} 598 599static __inline void 600remque(void *a) 601{ 602 struct quehead *element = (struct quehead *)a; 603 604 element->qh_link->qh_rlink = element->qh_rlink; 605 element->qh_rlink->qh_link = element->qh_link; 606 element->qh_rlink = 0; 607} 608 609#else /* !__CC_SUPPORTS___INLINE */ 610 611void insque(void *a, void *b); 612void remque(void *a); 613 614#endif /* __CC_SUPPORTS___INLINE */ 615 616#endif /* _KERNEL */ 617 618#endif /* !_SYS_QUEUE_H_ */ 619