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