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 * $FreeBSD$ 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 be traversed in either 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_FROM + + + + 92 * _FOREACH_SAFE + + + + 93 * _FOREACH_FROM_SAFE + + + + 94 * _FOREACH_REVERSE - - - + 95 * _FOREACH_REVERSE_FROM - - - + 96 * _FOREACH_REVERSE_SAFE - - - + 97 * _FOREACH_REVERSE_FROM_SAFE - - - + 98 * _INSERT_HEAD + + + + 99 * _INSERT_BEFORE - + - + 100 * _INSERT_AFTER + + + + 101 * _INSERT_TAIL - - + + 102 * _CONCAT - - + + 103 * _REMOVE_AFTER + - + - 104 * _REMOVE_HEAD + - + - 105 * _REMOVE + + + + 106 * _SWAP + + + + 107 * 108 */ 109#ifdef QUEUE_MACRO_DEBUG 110/* Store the last 2 places the queue element or head was altered */ 111struct qm_trace { 112 char * lastfile; 113 int lastline; 114 char * prevfile; 115 int prevline; 116}; 117 118#define TRACEBUF struct qm_trace trace; 119#define TRASHIT(x) do {(x) = (void *)-1;} while (0) 120#define QMD_SAVELINK(name, link) void **name = (void *)&(link) 121 122#define QMD_TRACE_HEAD(head) do { \ 123 (head)->trace.prevline = (head)->trace.lastline; \ 124 (head)->trace.prevfile = (head)->trace.lastfile; \ 125 (head)->trace.lastline = __LINE__; \ 126 (head)->trace.lastfile = __FILE__; \ 127} while (0) 128 129#define QMD_TRACE_ELEM(elem) do { \ 130 (elem)->trace.prevline = (elem)->trace.lastline; \ 131 (elem)->trace.prevfile = (elem)->trace.lastfile; \ 132 (elem)->trace.lastline = __LINE__; \ 133 (elem)->trace.lastfile = __FILE__; \ 134} while (0) 135 136#else 137#define QMD_TRACE_ELEM(elem) 138#define QMD_TRACE_HEAD(head) 139#define QMD_SAVELINK(name, link) 140#define TRACEBUF 141#define TRASHIT(x) 142#endif /* QUEUE_MACRO_DEBUG */ 143 144/* 145 * Singly-linked List declarations. 146 */ 147#define SLIST_HEAD(name, type) \ 148struct name { \ 149 struct type *slh_first; /* first element */ \ 150} 151 152#define SLIST_HEAD_INITIALIZER(head) \ 153 { NULL } 154 155#define SLIST_ENTRY(type) \ 156struct { \ 157 struct type *sle_next; /* next element */ \ 158} 159 160/* 161 * Singly-linked List functions. 162 */ 163#define SLIST_EMPTY(head) ((head)->slh_first == NULL) 164 165#define SLIST_FIRST(head) ((head)->slh_first) 166 167#define SLIST_FOREACH(var, head, field) \ 168 for ((var) = SLIST_FIRST((head)); \ 169 (var); \ 170 (var) = SLIST_NEXT((var), field)) 171 172#define SLIST_FOREACH_FROM(var, head, field) \ 173 for ((var) = ((var) ? (var) : SLIST_FIRST((head))); \ 174 (var); \ 175 (var) = SLIST_NEXT((var), field)) 176 177#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 178 for ((var) = SLIST_FIRST((head)); \ 179 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 180 (var) = (tvar)) 181 182#define SLIST_FOREACH_FROM_SAFE(var, head, field, tvar) \ 183 for ((var) = ((var) ? (var) : SLIST_FIRST((head))); \ 184 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 185 (var) = (tvar)) 186 187#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 188 for ((varp) = &SLIST_FIRST((head)); \ 189 ((var) = *(varp)) != NULL; \ 190 (varp) = &SLIST_NEXT((var), field)) 191 192#define SLIST_INIT(head) do { \ 193 SLIST_FIRST((head)) = NULL; \ 194} while (0) 195 196#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 197 SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 198 SLIST_NEXT((slistelm), field) = (elm); \ 199} while (0) 200 201#define SLIST_INSERT_HEAD(head, elm, field) do { \ 202 SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 203 SLIST_FIRST((head)) = (elm); \ 204} while (0) 205 206#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 207 208#define SLIST_REMOVE(head, elm, type, field) do { \ 209 QMD_SAVELINK(oldnext, (elm)->field.sle_next); \ 210 if (SLIST_FIRST((head)) == (elm)) { \ 211 SLIST_REMOVE_HEAD((head), field); \ 212 } \ 213 else { \ 214 struct type *curelm = SLIST_FIRST((head)); \ 215 while (SLIST_NEXT(curelm, field) != (elm)) \ 216 curelm = SLIST_NEXT(curelm, field); \ 217 SLIST_REMOVE_AFTER(curelm, field); \ 218 } \ 219 TRASHIT(*oldnext); \ 220} while (0) 221 222#define SLIST_REMOVE_AFTER(elm, field) do { \ 223 SLIST_NEXT(elm, field) = \ 224 SLIST_NEXT(SLIST_NEXT(elm, field), field); \ 225} while (0) 226 227#define SLIST_REMOVE_HEAD(head, field) do { \ 228 SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 229} while (0) 230 231#define SLIST_SWAP(head1, head2, type) do { \ 232 struct type *swap_first = SLIST_FIRST(head1); \ 233 SLIST_FIRST(head1) = SLIST_FIRST(head2); \ 234 SLIST_FIRST(head2) = swap_first; \ 235} while (0) 236 237/* 238 * Singly-linked Tail queue declarations. 239 */ 240#define STAILQ_HEAD(name, type) \ 241struct name { \ 242 struct type *stqh_first;/* first element */ \ 243 struct type **stqh_last;/* addr of last next element */ \ 244} 245 246#define STAILQ_HEAD_INITIALIZER(head) \ 247 { NULL, &(head).stqh_first } 248 249#define STAILQ_ENTRY(type) \ 250struct { \ 251 struct type *stqe_next; /* next element */ \ 252} 253 254/* 255 * Singly-linked Tail queue functions. 256 */ 257#define STAILQ_CONCAT(head1, head2) do { \ 258 if (!STAILQ_EMPTY((head2))) { \ 259 *(head1)->stqh_last = (head2)->stqh_first; \ 260 (head1)->stqh_last = (head2)->stqh_last; \ 261 STAILQ_INIT((head2)); \ 262 } \ 263} while (0) 264 265#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL) 266 267#define STAILQ_FIRST(head) ((head)->stqh_first) 268 269#define STAILQ_FOREACH(var, head, field) \ 270 for((var) = STAILQ_FIRST((head)); \ 271 (var); \ 272 (var) = STAILQ_NEXT((var), field)) 273 274#define STAILQ_FOREACH_FROM(var, head, field) \ 275 for ((var) = ((var) ? (var) : STAILQ_FIRST((head))); \ 276 (var); \ 277 (var) = STAILQ_NEXT((var), field)) 278 279#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 280 for ((var) = STAILQ_FIRST((head)); \ 281 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 282 (var) = (tvar)) 283 284#define STAILQ_FOREACH_FROM_SAFE(var, head, field, tvar) \ 285 for ((var) = ((var) ? (var) : STAILQ_FIRST((head))); \ 286 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 287 (var) = (tvar)) 288 289#define STAILQ_INIT(head) do { \ 290 STAILQ_FIRST((head)) = NULL; \ 291 (head)->stqh_last = &STAILQ_FIRST((head)); \ 292} while (0) 293 294#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 295 if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 296 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 297 STAILQ_NEXT((tqelm), field) = (elm); \ 298} while (0) 299 300#define STAILQ_INSERT_HEAD(head, elm, field) do { \ 301 if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 302 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 303 STAILQ_FIRST((head)) = (elm); \ 304} while (0) 305 306#define STAILQ_INSERT_TAIL(head, elm, field) do { \ 307 STAILQ_NEXT((elm), field) = NULL; \ 308 *(head)->stqh_last = (elm); \ 309 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 310} while (0) 311 312#define STAILQ_LAST(head, type, field) \ 313 (STAILQ_EMPTY((head)) ? NULL : \ 314 __containerof((head)->stqh_last, struct type, field.stqe_next)) 315 316#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 317 318#define STAILQ_REMOVE(head, elm, type, field) do { \ 319 QMD_SAVELINK(oldnext, (elm)->field.stqe_next); \ 320 if (STAILQ_FIRST((head)) == (elm)) { \ 321 STAILQ_REMOVE_HEAD((head), field); \ 322 } \ 323 else { \ 324 struct type *curelm = STAILQ_FIRST((head)); \ 325 while (STAILQ_NEXT(curelm, field) != (elm)) \ 326 curelm = STAILQ_NEXT(curelm, field); \ 327 STAILQ_REMOVE_AFTER(head, curelm, field); \ 328 } \ 329 TRASHIT(*oldnext); \ 330} while (0) 331 332#define STAILQ_REMOVE_AFTER(head, elm, field) do { \ 333 if ((STAILQ_NEXT(elm, field) = \ 334 STAILQ_NEXT(STAILQ_NEXT(elm, field), field)) == NULL) \ 335 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 336} while (0) 337 338#define STAILQ_REMOVE_HEAD(head, field) do { \ 339 if ((STAILQ_FIRST((head)) = \ 340 STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 341 (head)->stqh_last = &STAILQ_FIRST((head)); \ 342} while (0) 343 344#define STAILQ_SWAP(head1, head2, type) do { \ 345 struct type *swap_first = STAILQ_FIRST(head1); \ 346 struct type **swap_last = (head1)->stqh_last; \ 347 STAILQ_FIRST(head1) = STAILQ_FIRST(head2); \ 348 (head1)->stqh_last = (head2)->stqh_last; \ 349 STAILQ_FIRST(head2) = swap_first; \ 350 (head2)->stqh_last = swap_last; \ 351 if (STAILQ_EMPTY(head1)) \ 352 (head1)->stqh_last = &STAILQ_FIRST(head1); \ 353 if (STAILQ_EMPTY(head2)) \ 354 (head2)->stqh_last = &STAILQ_FIRST(head2); \ 355} while (0) 356 357 358/* 359 * List declarations. 360 */ 361#define LIST_HEAD(name, type) \ 362struct name { \ 363 struct type *lh_first; /* first element */ \ 364} 365 366#define LIST_HEAD_INITIALIZER(head) \ 367 { NULL } 368 369#define LIST_ENTRY(type) \ 370struct { \ 371 struct type *le_next; /* next element */ \ 372 struct type **le_prev; /* address of previous next element */ \ 373} 374 375/* 376 * List functions. 377 */ 378 379#if (defined(_KERNEL) && defined(INVARIANTS)) 380#define QMD_LIST_CHECK_HEAD(head, field) do { \ 381 if (LIST_FIRST((head)) != NULL && \ 382 LIST_FIRST((head))->field.le_prev != \ 383 &LIST_FIRST((head))) \ 384 panic("Bad list head %p first->prev != head", (head)); \ 385} while (0) 386 387#define QMD_LIST_CHECK_NEXT(elm, field) do { \ 388 if (LIST_NEXT((elm), field) != NULL && \ 389 LIST_NEXT((elm), field)->field.le_prev != \ 390 &((elm)->field.le_next)) \ 391 panic("Bad link elm %p next->prev != elm", (elm)); \ 392} while (0) 393 394#define QMD_LIST_CHECK_PREV(elm, field) do { \ 395 if (*(elm)->field.le_prev != (elm)) \ 396 panic("Bad link elm %p prev->next != elm", (elm)); \ 397} while (0) 398#else 399#define QMD_LIST_CHECK_HEAD(head, field) 400#define QMD_LIST_CHECK_NEXT(elm, field) 401#define QMD_LIST_CHECK_PREV(elm, field) 402#endif /* (_KERNEL && INVARIANTS) */ 403 404#define LIST_EMPTY(head) ((head)->lh_first == NULL) 405 406#define LIST_FIRST(head) ((head)->lh_first) 407 408#define LIST_FOREACH(var, head, field) \ 409 for ((var) = LIST_FIRST((head)); \ 410 (var); \ 411 (var) = LIST_NEXT((var), field)) 412 413#define LIST_FOREACH_FROM(var, head, field) \ 414 for ((var) = ((var) ? (var) : LIST_FIRST((head))); \ 415 (var); \ 416 (var) = LIST_NEXT((var), field)) 417 418#define LIST_FOREACH_SAFE(var, head, field, tvar) \ 419 for ((var) = LIST_FIRST((head)); \ 420 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 421 (var) = (tvar)) 422 423#define LIST_FOREACH_FROM_SAFE(var, head, field, tvar) \ 424 for ((var) = ((var) ? (var) : LIST_FIRST((head))); \ 425 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 426 (var) = (tvar)) 427 428#define LIST_INIT(head) do { \ 429 LIST_FIRST((head)) = NULL; \ 430} while (0) 431 432#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 433 QMD_LIST_CHECK_NEXT(listelm, field); \ 434 if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 435 LIST_NEXT((listelm), field)->field.le_prev = \ 436 &LIST_NEXT((elm), field); \ 437 LIST_NEXT((listelm), field) = (elm); \ 438 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 439} while (0) 440 441#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 442 QMD_LIST_CHECK_PREV(listelm, field); \ 443 (elm)->field.le_prev = (listelm)->field.le_prev; \ 444 LIST_NEXT((elm), field) = (listelm); \ 445 *(listelm)->field.le_prev = (elm); \ 446 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 447} while (0) 448 449#define LIST_INSERT_HEAD(head, elm, field) do { \ 450 QMD_LIST_CHECK_HEAD((head), field); \ 451 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 452 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 453 LIST_FIRST((head)) = (elm); \ 454 (elm)->field.le_prev = &LIST_FIRST((head)); \ 455} while (0) 456 457#define LIST_NEXT(elm, field) ((elm)->field.le_next) 458 459#define LIST_PREV(elm, head, type, field) \ 460 ((elm)->field.le_prev == &LIST_FIRST((head)) ? NULL : \ 461 __containerof((elm)->field.le_prev, struct type, field.le_next)) 462 463#define LIST_REMOVE(elm, field) do { \ 464 QMD_SAVELINK(oldnext, (elm)->field.le_next); \ 465 QMD_SAVELINK(oldprev, (elm)->field.le_prev); \ 466 QMD_LIST_CHECK_NEXT(elm, field); \ 467 QMD_LIST_CHECK_PREV(elm, field); \ 468 if (LIST_NEXT((elm), field) != NULL) \ 469 LIST_NEXT((elm), field)->field.le_prev = \ 470 (elm)->field.le_prev; \ 471 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 472 TRASHIT(*oldnext); \ 473 TRASHIT(*oldprev); \ 474} while (0) 475 476#define LIST_SWAP(head1, head2, type, field) do { \ 477 struct type *swap_tmp = LIST_FIRST((head1)); \ 478 LIST_FIRST((head1)) = LIST_FIRST((head2)); \ 479 LIST_FIRST((head2)) = swap_tmp; \ 480 if ((swap_tmp = LIST_FIRST((head1))) != NULL) \ 481 swap_tmp->field.le_prev = &LIST_FIRST((head1)); \ 482 if ((swap_tmp = LIST_FIRST((head2))) != NULL) \ 483 swap_tmp->field.le_prev = &LIST_FIRST((head2)); \ 484} while (0) 485 486/* 487 * Tail queue declarations. 488 */ 489#define TAILQ_HEAD(name, type) \ 490struct name { \ 491 struct type *tqh_first; /* first element */ \ 492 struct type **tqh_last; /* addr of last next element */ \ 493 TRACEBUF \ 494} 495 496#define TAILQ_HEAD_INITIALIZER(head) \ 497 { NULL, &(head).tqh_first } 498 499#define TAILQ_ENTRY(type) \ 500struct { \ 501 struct type *tqe_next; /* next element */ \ 502 struct type **tqe_prev; /* address of previous next element */ \ 503 TRACEBUF \ 504} 505 506/* 507 * Tail queue functions. 508 */ 509#if (defined(_KERNEL) && defined(INVARIANTS)) 510#define QMD_TAILQ_CHECK_HEAD(head, field) do { \ 511 if (!TAILQ_EMPTY(head) && \ 512 TAILQ_FIRST((head))->field.tqe_prev != \ 513 &TAILQ_FIRST((head))) \ 514 panic("Bad tailq head %p first->prev != head", (head)); \ 515} while (0) 516 517#define QMD_TAILQ_CHECK_TAIL(head, field) do { \ 518 if (*(head)->tqh_last != NULL) \ 519 panic("Bad tailq NEXT(%p->tqh_last) != NULL", (head)); \ 520} while (0) 521 522#define QMD_TAILQ_CHECK_NEXT(elm, field) do { \ 523 if (TAILQ_NEXT((elm), field) != NULL && \ 524 TAILQ_NEXT((elm), field)->field.tqe_prev != \ 525 &((elm)->field.tqe_next)) \ 526 panic("Bad link elm %p next->prev != elm", (elm)); \ 527} while (0) 528 529#define QMD_TAILQ_CHECK_PREV(elm, field) do { \ 530 if (*(elm)->field.tqe_prev != (elm)) \ 531 panic("Bad link elm %p prev->next != elm", (elm)); \ 532} while (0) 533#else 534#define QMD_TAILQ_CHECK_HEAD(head, field) 535#define QMD_TAILQ_CHECK_TAIL(head, headname) 536#define QMD_TAILQ_CHECK_NEXT(elm, field) 537#define QMD_TAILQ_CHECK_PREV(elm, field) 538#endif /* (_KERNEL && INVARIANTS) */ 539 540#define TAILQ_CONCAT(head1, head2, field) do { \ 541 if (!TAILQ_EMPTY(head2)) { \ 542 *(head1)->tqh_last = (head2)->tqh_first; \ 543 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 544 (head1)->tqh_last = (head2)->tqh_last; \ 545 TAILQ_INIT((head2)); \ 546 QMD_TRACE_HEAD(head1); \ 547 QMD_TRACE_HEAD(head2); \ 548 } \ 549} while (0) 550 551#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 552 553#define TAILQ_FIRST(head) ((head)->tqh_first) 554 555#define TAILQ_FOREACH(var, head, field) \ 556 for ((var) = TAILQ_FIRST((head)); \ 557 (var); \ 558 (var) = TAILQ_NEXT((var), field)) 559 560#define TAILQ_FOREACH_FROM(var, head, field) \ 561 for ((var) = ((var) ? (var) : TAILQ_FIRST((head))); \ 562 (var); \ 563 (var) = TAILQ_NEXT((var), field)) 564 565#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 566 for ((var) = TAILQ_FIRST((head)); \ 567 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 568 (var) = (tvar)) 569 570#define TAILQ_FOREACH_FROM_SAFE(var, head, field, tvar) \ 571 for ((var) = ((var) ? (var) : TAILQ_FIRST((head))); \ 572 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 573 (var) = (tvar)) 574 575#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 576 for ((var) = TAILQ_LAST((head), headname); \ 577 (var); \ 578 (var) = TAILQ_PREV((var), headname, field)) 579 580#define TAILQ_FOREACH_REVERSE_FROM(var, head, headname, field) \ 581 for ((var) = ((var) ? (var) : TAILQ_LAST((head), headname)); \ 582 (var); \ 583 (var) = TAILQ_PREV((var), headname, field)) 584 585#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 586 for ((var) = TAILQ_LAST((head), headname); \ 587 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 588 (var) = (tvar)) 589 590#define TAILQ_FOREACH_REVERSE_FROM_SAFE(var, head, headname, field, tvar) \ 591 for ((var) = ((var) ? (var) : TAILQ_LAST((head), headname)); \ 592 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 593 (var) = (tvar)) 594 595#define TAILQ_INIT(head) do { \ 596 TAILQ_FIRST((head)) = NULL; \ 597 (head)->tqh_last = &TAILQ_FIRST((head)); \ 598 QMD_TRACE_HEAD(head); \ 599} while (0) 600 601#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 602 QMD_TAILQ_CHECK_NEXT(listelm, field); \ 603 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 604 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 605 &TAILQ_NEXT((elm), field); \ 606 else { \ 607 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 608 QMD_TRACE_HEAD(head); \ 609 } \ 610 TAILQ_NEXT((listelm), field) = (elm); \ 611 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 612 QMD_TRACE_ELEM(&(elm)->field); \ 613 QMD_TRACE_ELEM(&listelm->field); \ 614} while (0) 615 616#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 617 QMD_TAILQ_CHECK_PREV(listelm, field); \ 618 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 619 TAILQ_NEXT((elm), field) = (listelm); \ 620 *(listelm)->field.tqe_prev = (elm); \ 621 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 622 QMD_TRACE_ELEM(&(elm)->field); \ 623 QMD_TRACE_ELEM(&listelm->field); \ 624} while (0) 625 626#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 627 QMD_TAILQ_CHECK_HEAD(head, field); \ 628 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 629 TAILQ_FIRST((head))->field.tqe_prev = \ 630 &TAILQ_NEXT((elm), field); \ 631 else \ 632 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 633 TAILQ_FIRST((head)) = (elm); \ 634 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 635 QMD_TRACE_HEAD(head); \ 636 QMD_TRACE_ELEM(&(elm)->field); \ 637} while (0) 638 639#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 640 QMD_TAILQ_CHECK_TAIL(head, field); \ 641 TAILQ_NEXT((elm), field) = NULL; \ 642 (elm)->field.tqe_prev = (head)->tqh_last; \ 643 *(head)->tqh_last = (elm); \ 644 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 645 QMD_TRACE_HEAD(head); \ 646 QMD_TRACE_ELEM(&(elm)->field); \ 647} while (0) 648 649#define TAILQ_LAST(head, headname) \ 650 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 651 652#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 653 654#define TAILQ_PREV(elm, headname, field) \ 655 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 656 657#define TAILQ_REMOVE(head, elm, field) do { \ 658 QMD_SAVELINK(oldnext, (elm)->field.tqe_next); \ 659 QMD_SAVELINK(oldprev, (elm)->field.tqe_prev); \ 660 QMD_TAILQ_CHECK_NEXT(elm, field); \ 661 QMD_TAILQ_CHECK_PREV(elm, field); \ 662 if ((TAILQ_NEXT((elm), field)) != NULL) \ 663 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 664 (elm)->field.tqe_prev; \ 665 else { \ 666 (head)->tqh_last = (elm)->field.tqe_prev; \ 667 QMD_TRACE_HEAD(head); \ 668 } \ 669 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 670 TRASHIT(*oldnext); \ 671 TRASHIT(*oldprev); \ 672 QMD_TRACE_ELEM(&(elm)->field); \ 673} while (0) 674 675#define TAILQ_SWAP(head1, head2, type, field) do { \ 676 struct type *swap_first = (head1)->tqh_first; \ 677 struct type **swap_last = (head1)->tqh_last; \ 678 (head1)->tqh_first = (head2)->tqh_first; \ 679 (head1)->tqh_last = (head2)->tqh_last; \ 680 (head2)->tqh_first = swap_first; \ 681 (head2)->tqh_last = swap_last; \ 682 if ((swap_first = (head1)->tqh_first) != NULL) \ 683 swap_first->field.tqe_prev = &(head1)->tqh_first; \ 684 else \ 685 (head1)->tqh_last = &(head1)->tqh_first; \ 686 if ((swap_first = (head2)->tqh_first) != NULL) \ 687 swap_first->field.tqe_prev = &(head2)->tqh_first; \ 688 else \ 689 (head2)->tqh_last = &(head2)->tqh_first; \ 690} while (0) 691 692#endif /* !_SYS_QUEUE_H_ */ 693