1/* 2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28/*- 29 * Copyright (c) 1991, 1993 30 * The Regents of the University of California. All rights reserved. 31 * 32 * Redistribution and use in source and binary forms, with or without 33 * modification, are permitted provided that the following conditions 34 * are met: 35 * 1. Redistributions of source code must retain the above copyright 36 * notice, this list of conditions and the following disclaimer. 37 * 2. Redistributions in binary form must reproduce the above copyright 38 * notice, this list of conditions and the following disclaimer in the 39 * documentation and/or other materials provided with the distribution. 40 * 4. Neither the name of the University nor the names of its contributors 41 * may be used to endorse or promote products derived from this software 42 * without specific prior written permission. 43 * 44 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 45 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 46 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 47 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 48 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 49 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 50 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 51 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 52 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 53 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 54 * SUCH DAMAGE. 55 * 56 * @(#)queue.h 8.5 (Berkeley) 8/20/94 57 */ 58 59#ifndef _SYS_QUEUE_H_ 60#define _SYS_QUEUE_H_ 61 62/* 63 * This file defines five types of data structures: singly-linked lists, 64 * singly-linked tail queues, lists, tail queues, and circular queues. 65 * 66 * A singly-linked list is headed by a single forward pointer. The elements 67 * are singly linked for minimum space and pointer manipulation overhead at 68 * the expense of O(n) removal for arbitrary elements. New elements can be 69 * added to the list after an existing element or at the head of the list. 70 * Elements being removed from the head of the list should use the explicit 71 * macro for this purpose for optimum efficiency. A singly-linked list may 72 * only be traversed in the forward direction. Singly-linked lists are ideal 73 * for applications with large datasets and few or no removals or for 74 * implementing a LIFO queue. 75 * 76 * A singly-linked tail queue is headed by a pair of pointers, one to the 77 * head of the list and the other to the tail of the list. The elements are 78 * singly linked for minimum space and pointer manipulation overhead at the 79 * expense of O(n) removal for arbitrary elements. New elements can be added 80 * to the list after an existing element, at the head of the list, or at the 81 * end of the list. Elements being removed from the head of the tail queue 82 * should use the explicit macro for this purpose for optimum efficiency. 83 * A singly-linked tail queue may only be traversed in the forward direction. 84 * Singly-linked tail queues are ideal for applications with large datasets 85 * and few or no removals or for implementing a FIFO queue. 86 * 87 * A list is headed by a single forward pointer (or an array of forward 88 * pointers for a hash table header). The elements are doubly linked 89 * so that an arbitrary element can be removed without a need to 90 * traverse the list. New elements can be added to the list before 91 * or after an existing element or at the head of the list. A list 92 * may only be traversed in the forward direction. 93 * 94 * A tail queue is headed by a pair of pointers, one to the head of the 95 * list and the other to the tail of the list. The elements are doubly 96 * linked so that an arbitrary element can be removed without a need to 97 * traverse the list. New elements can be added to the list before or 98 * after an existing element, at the head of the list, or at the end of 99 * the list. A tail queue may be traversed in either direction. 100 * 101 * A circle queue is headed by a pair of pointers, one to the head of the 102 * list and the other to the tail of the list. The elements are doubly 103 * linked so that an arbitrary element can be removed without a need to 104 * traverse the list. New elements can be added to the list before or after 105 * an existing element, at the head of the list, or at the end of the list. 106 * A circle queue may be traversed in either direction, but has a more 107 * complex end of list detection. 108 * Note that circle queues are deprecated, because, as the removal log 109 * in FreeBSD states, "CIRCLEQs are a disgrace to everything Knuth taught 110 * us in Volume 1 Chapter 2. [...] Use TAILQ instead, it provides the same 111 * functionality." Code using them will continue to compile, but they 112 * are no longer documented on the man page. 113 * 114 * For details on the use of these macros, see the queue(3) manual page. 115 * 116 * 117 * SLIST LIST STAILQ TAILQ CIRCLEQ 118 * _HEAD + + + + + 119 * _HEAD_INITIALIZER + + + + - 120 * _ENTRY + + + + + 121 * _INIT + + + + + 122 * _EMPTY + + + + + 123 * _FIRST + + + + + 124 * _NEXT + + + + + 125 * _PREV - - - + + 126 * _LAST - - + + + 127 * _FOREACH + + + + + 128 * _FOREACH_SAFE + + + + - 129 * _FOREACH_REVERSE - - - + - 130 * _FOREACH_REVERSE_SAFE - - - + - 131 * _INSERT_HEAD + + + + + 132 * _INSERT_BEFORE - + - + + 133 * _INSERT_AFTER + + + + + 134 * _INSERT_TAIL - - + + + 135 * _CONCAT - - + + - 136 * _REMOVE_AFTER + - + - - 137 * _REMOVE_HEAD + - + - - 138 * _REMOVE_HEAD_UNTIL - - + - - 139 * _REMOVE + + + + + 140 * _SWAP - + + + - 141 * 142 */ 143#ifdef QUEUE_MACRO_DEBUG 144/* Store the last 2 places the queue element or head was altered */ 145struct qm_trace { 146 char * lastfile; 147 int lastline; 148 char * prevfile; 149 int prevline; 150}; 151 152#define TRACEBUF struct qm_trace trace; 153#define TRASHIT(x) do {(x) = (void *)-1;} while (0) 154 155#define QMD_TRACE_HEAD(head) do { \ 156 (head)->trace.prevline = (head)->trace.lastline; \ 157 (head)->trace.prevfile = (head)->trace.lastfile; \ 158 (head)->trace.lastline = __LINE__; \ 159 (head)->trace.lastfile = __FILE__; \ 160} while (0) 161 162#define QMD_TRACE_ELEM(elem) do { \ 163 (elem)->trace.prevline = (elem)->trace.lastline; \ 164 (elem)->trace.prevfile = (elem)->trace.lastfile; \ 165 (elem)->trace.lastline = __LINE__; \ 166 (elem)->trace.lastfile = __FILE__; \ 167} while (0) 168 169#else 170#define QMD_TRACE_ELEM(elem) 171#define QMD_TRACE_HEAD(head) 172#define TRACEBUF 173#define TRASHIT(x) 174#endif /* QUEUE_MACRO_DEBUG */ 175 176/* 177 * Horrible macros to enable use of code that was meant to be C-specific 178 * (and which push struct onto type) in C++; without these, C++ code 179 * that uses these macros in the context of a class will blow up 180 * due to "struct" being preprended to "type" by the macros, causing 181 * inconsistent use of tags. 182 * 183 * This approach is necessary because these are macros; we have to use 184 * these on a per-macro basis (because the queues are implemented as 185 * macros, disabling this warning in the scope of the header file is 186 * insufficient), whuch means we can't use #pragma, and have to use 187 * _Pragma. We only need to use these for the queue macros that 188 * prepend "struct" to "type" and will cause C++ to blow up. 189 */ 190#if defined(__clang__) && defined(__cplusplus) 191#define __MISMATCH_TAGS_PUSH \ 192 _Pragma("clang diagnostic push") \ 193 _Pragma("clang diagnostic ignored \"-Wmismatched-tags\"") 194#define __MISMATCH_TAGS_POP \ 195 _Pragma("clang diagnostic pop") 196#else 197#define __MISMATCH_TAGS_PUSH 198#define __MISMATCH_TAGS_POP 199#endif 200 201/* 202 * Singly-linked List declarations. 203 */ 204#define SLIST_HEAD(name, type) \ 205__MISMATCH_TAGS_PUSH \ 206struct name { \ 207 struct type *slh_first; /* first element */ \ 208} \ 209__MISMATCH_TAGS_POP 210 211#define SLIST_HEAD_INITIALIZER(head) \ 212 { NULL } 213 214#define SLIST_ENTRY(type) \ 215__MISMATCH_TAGS_PUSH \ 216struct { \ 217 struct type *sle_next; /* next element */ \ 218} \ 219__MISMATCH_TAGS_POP 220 221/* 222 * Singly-linked List functions. 223 */ 224#define SLIST_EMPTY(head) ((head)->slh_first == NULL) 225 226#define SLIST_FIRST(head) ((head)->slh_first) 227 228#define SLIST_FOREACH(var, head, field) \ 229 for ((var) = SLIST_FIRST((head)); \ 230 (var); \ 231 (var) = SLIST_NEXT((var), field)) 232 233#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 234 for ((var) = SLIST_FIRST((head)); \ 235 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 236 (var) = (tvar)) 237 238#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 239 for ((varp) = &SLIST_FIRST((head)); \ 240 ((var) = *(varp)) != NULL; \ 241 (varp) = &SLIST_NEXT((var), field)) 242 243#define SLIST_INIT(head) do { \ 244 SLIST_FIRST((head)) = NULL; \ 245} while (0) 246 247#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 248 SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 249 SLIST_NEXT((slistelm), field) = (elm); \ 250} while (0) 251 252#define SLIST_INSERT_HEAD(head, elm, field) do { \ 253 SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 254 SLIST_FIRST((head)) = (elm); \ 255} while (0) 256 257#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 258 259#define SLIST_REMOVE(head, elm, type, field) \ 260__MISMATCH_TAGS_PUSH \ 261do { \ 262 if (SLIST_FIRST((head)) == (elm)) { \ 263 SLIST_REMOVE_HEAD((head), field); \ 264 } \ 265 else { \ 266 struct type *curelm = SLIST_FIRST((head)); \ 267 while (SLIST_NEXT(curelm, field) != (elm)) \ 268 curelm = SLIST_NEXT(curelm, field); \ 269 SLIST_REMOVE_AFTER(curelm, field); \ 270 } \ 271 TRASHIT((elm)->field.sle_next); \ 272} while (0) \ 273__MISMATCH_TAGS_POP 274 275#define SLIST_REMOVE_AFTER(elm, field) do { \ 276 SLIST_NEXT(elm, field) = \ 277 SLIST_NEXT(SLIST_NEXT(elm, field), field); \ 278} while (0) 279 280#define SLIST_REMOVE_HEAD(head, field) do { \ 281 SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 282} while (0) 283 284/* 285 * Singly-linked Tail queue declarations. 286 */ 287#define STAILQ_HEAD(name, type) \ 288__MISMATCH_TAGS_PUSH \ 289struct name { \ 290 struct type *stqh_first;/* first element */ \ 291 struct type **stqh_last;/* addr of last next element */ \ 292} \ 293__MISMATCH_TAGS_POP 294 295#define STAILQ_HEAD_INITIALIZER(head) \ 296 { NULL, &(head).stqh_first } 297 298#define STAILQ_ENTRY(type) \ 299__MISMATCH_TAGS_PUSH \ 300struct { \ 301 struct type *stqe_next; /* next element */ \ 302} \ 303__MISMATCH_TAGS_POP 304 305/* 306 * Singly-linked Tail queue functions. 307 */ 308#define STAILQ_CONCAT(head1, head2) do { \ 309 if (!STAILQ_EMPTY((head2))) { \ 310 *(head1)->stqh_last = (head2)->stqh_first; \ 311 (head1)->stqh_last = (head2)->stqh_last; \ 312 STAILQ_INIT((head2)); \ 313 } \ 314} while (0) 315 316#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL) 317 318#define STAILQ_FIRST(head) ((head)->stqh_first) 319 320#define STAILQ_FOREACH(var, head, field) \ 321 for((var) = STAILQ_FIRST((head)); \ 322 (var); \ 323 (var) = STAILQ_NEXT((var), field)) 324 325 326#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 327 for ((var) = STAILQ_FIRST((head)); \ 328 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 329 (var) = (tvar)) 330 331#define STAILQ_INIT(head) do { \ 332 STAILQ_FIRST((head)) = NULL; \ 333 (head)->stqh_last = &STAILQ_FIRST((head)); \ 334} while (0) 335 336#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 337 if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 338 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 339 STAILQ_NEXT((tqelm), field) = (elm); \ 340} while (0) 341 342#define STAILQ_INSERT_HEAD(head, elm, field) do { \ 343 if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 344 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 345 STAILQ_FIRST((head)) = (elm); \ 346} while (0) 347 348#define STAILQ_INSERT_TAIL(head, elm, field) do { \ 349 STAILQ_NEXT((elm), field) = NULL; \ 350 *(head)->stqh_last = (elm); \ 351 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 352} while (0) 353 354#define STAILQ_LAST(head, type, field) \ 355__MISMATCH_TAGS_PUSH \ 356 (STAILQ_EMPTY((head)) ? \ 357 NULL : \ 358 ((struct type *)(void *) \ 359 ((char *)((head)->stqh_last) - __offsetof(struct type, field))))\ 360__MISMATCH_TAGS_POP 361 362#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 363 364#define STAILQ_REMOVE(head, elm, type, field) \ 365__MISMATCH_TAGS_PUSH \ 366do { \ 367 if (STAILQ_FIRST((head)) == (elm)) { \ 368 STAILQ_REMOVE_HEAD((head), field); \ 369 } \ 370 else { \ 371 struct type *curelm = STAILQ_FIRST((head)); \ 372 while (STAILQ_NEXT(curelm, field) != (elm)) \ 373 curelm = STAILQ_NEXT(curelm, field); \ 374 STAILQ_REMOVE_AFTER(head, curelm, field); \ 375 } \ 376 TRASHIT((elm)->field.stqe_next); \ 377} while (0) \ 378__MISMATCH_TAGS_POP 379 380#define STAILQ_REMOVE_HEAD(head, field) do { \ 381 if ((STAILQ_FIRST((head)) = \ 382 STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 383 (head)->stqh_last = &STAILQ_FIRST((head)); \ 384} while (0) 385 386#define STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do { \ 387 if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL) \ 388 (head)->stqh_last = &STAILQ_FIRST((head)); \ 389} while (0) 390 391#define STAILQ_REMOVE_AFTER(head, elm, field) do { \ 392 if ((STAILQ_NEXT(elm, field) = \ 393 STAILQ_NEXT(STAILQ_NEXT(elm, field), field)) == NULL) \ 394 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 395} while (0) 396 397#define STAILQ_SWAP(head1, head2, type) \ 398__MISMATCH_TAGS_PUSH \ 399do { \ 400 struct type *swap_first = STAILQ_FIRST(head1); \ 401 struct type **swap_last = (head1)->stqh_last; \ 402 STAILQ_FIRST(head1) = STAILQ_FIRST(head2); \ 403 (head1)->stqh_last = (head2)->stqh_last; \ 404 STAILQ_FIRST(head2) = swap_first; \ 405 (head2)->stqh_last = swap_last; \ 406 if (STAILQ_EMPTY(head1)) \ 407 (head1)->stqh_last = &STAILQ_FIRST(head1); \ 408 if (STAILQ_EMPTY(head2)) \ 409 (head2)->stqh_last = &STAILQ_FIRST(head2); \ 410} while (0) \ 411__MISMATCH_TAGS_POP 412 413 414/* 415 * List declarations. 416 */ 417#define LIST_HEAD(name, type) \ 418__MISMATCH_TAGS_PUSH \ 419struct name { \ 420 struct type *lh_first; /* first element */ \ 421} \ 422__MISMATCH_TAGS_POP 423 424#define LIST_HEAD_INITIALIZER(head) \ 425 { NULL } 426 427#define LIST_ENTRY(type) \ 428__MISMATCH_TAGS_PUSH \ 429struct { \ 430 struct type *le_next; /* next element */ \ 431 struct type **le_prev; /* address of previous next element */ \ 432} \ 433__MISMATCH_TAGS_POP 434 435/* 436 * List functions. 437 */ 438 439#if (defined(_KERNEL) && defined(INVARIANTS)) || defined(QUEUE_MACRO_DEBUG) 440#define QMD_LIST_CHECK_HEAD(head, field) do { \ 441 if (LIST_FIRST((head)) != NULL && \ 442 LIST_FIRST((head))->field.le_prev != \ 443 &LIST_FIRST((head))) \ 444 panic("Bad list head %p first->prev != head", (head)); \ 445} while (0) 446 447#define QMD_LIST_CHECK_NEXT(elm, field) do { \ 448 if (LIST_NEXT((elm), field) != NULL && \ 449 LIST_NEXT((elm), field)->field.le_prev != \ 450 &((elm)->field.le_next)) \ 451 panic("Bad link elm %p next->prev != elm", (elm)); \ 452} while (0) 453 454#define QMD_LIST_CHECK_PREV(elm, field) do { \ 455 if (*(elm)->field.le_prev != (elm)) \ 456 panic("Bad link elm %p prev->next != elm", (elm)); \ 457} while (0) 458#else 459#define QMD_LIST_CHECK_HEAD(head, field) 460#define QMD_LIST_CHECK_NEXT(elm, field) 461#define QMD_LIST_CHECK_PREV(elm, field) 462#endif /* (_KERNEL && INVARIANTS) || QUEUE_MACRO_DEBUG */ 463 464#define LIST_EMPTY(head) ((head)->lh_first == NULL) 465 466#define LIST_FIRST(head) ((head)->lh_first) 467 468#define LIST_FOREACH(var, head, field) \ 469 for ((var) = LIST_FIRST((head)); \ 470 (var); \ 471 (var) = LIST_NEXT((var), field)) 472 473#define LIST_FOREACH_SAFE(var, head, field, tvar) \ 474 for ((var) = LIST_FIRST((head)); \ 475 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 476 (var) = (tvar)) 477 478#define LIST_INIT(head) do { \ 479 LIST_FIRST((head)) = NULL; \ 480} while (0) 481 482#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 483 QMD_LIST_CHECK_NEXT(listelm, field); \ 484 if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 485 LIST_NEXT((listelm), field)->field.le_prev = \ 486 &LIST_NEXT((elm), field); \ 487 LIST_NEXT((listelm), field) = (elm); \ 488 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 489} while (0) 490 491#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 492 QMD_LIST_CHECK_PREV(listelm, field); \ 493 (elm)->field.le_prev = (listelm)->field.le_prev; \ 494 LIST_NEXT((elm), field) = (listelm); \ 495 *(listelm)->field.le_prev = (elm); \ 496 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 497} while (0) 498 499#define LIST_INSERT_HEAD(head, elm, field) do { \ 500 QMD_LIST_CHECK_HEAD((head), field); \ 501 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 502 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 503 LIST_FIRST((head)) = (elm); \ 504 (elm)->field.le_prev = &LIST_FIRST((head)); \ 505} while (0) 506 507#define LIST_NEXT(elm, field) ((elm)->field.le_next) 508 509#define LIST_REMOVE(elm, field) do { \ 510 QMD_LIST_CHECK_NEXT(elm, field); \ 511 QMD_LIST_CHECK_PREV(elm, field); \ 512 if (LIST_NEXT((elm), field) != NULL) \ 513 LIST_NEXT((elm), field)->field.le_prev = \ 514 (elm)->field.le_prev; \ 515 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 516 TRASHIT((elm)->field.le_next); \ 517 TRASHIT((elm)->field.le_prev); \ 518} while (0) 519 520#define LIST_SWAP(head1, head2, type, field) \ 521__MISMATCH_TAGS_PUSH \ 522do { \ 523 struct type *swap_tmp = LIST_FIRST((head1)); \ 524 LIST_FIRST((head1)) = LIST_FIRST((head2)); \ 525 LIST_FIRST((head2)) = swap_tmp; \ 526 if ((swap_tmp = LIST_FIRST((head1))) != NULL) \ 527 swap_tmp->field.le_prev = &LIST_FIRST((head1)); \ 528 if ((swap_tmp = LIST_FIRST((head2))) != NULL) \ 529 swap_tmp->field.le_prev = &LIST_FIRST((head2)); \ 530} while (0) \ 531__MISMATCH_TAGS_POP 532 533/* 534 * Tail queue declarations. 535 */ 536#define TAILQ_HEAD(name, type) \ 537__MISMATCH_TAGS_PUSH \ 538struct name { \ 539 struct type *tqh_first; /* first element */ \ 540 struct type **tqh_last; /* addr of last next element */ \ 541 TRACEBUF \ 542} \ 543__MISMATCH_TAGS_POP 544 545#define TAILQ_HEAD_INITIALIZER(head) \ 546 { NULL, &(head).tqh_first } 547 548#define TAILQ_ENTRY(type) \ 549__MISMATCH_TAGS_PUSH \ 550struct { \ 551 struct type *tqe_next; /* next element */ \ 552 struct type **tqe_prev; /* address of previous next element */ \ 553 TRACEBUF \ 554} \ 555__MISMATCH_TAGS_POP 556 557/* 558 * Tail queue functions. 559 */ 560#define TAILQ_CONCAT(head1, head2, field) do { \ 561 if (!TAILQ_EMPTY(head2)) { \ 562 *(head1)->tqh_last = (head2)->tqh_first; \ 563 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 564 (head1)->tqh_last = (head2)->tqh_last; \ 565 TAILQ_INIT((head2)); \ 566 QMD_TRACE_HEAD(head1); \ 567 QMD_TRACE_HEAD(head2); \ 568 } \ 569} while (0) 570 571#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 572 573#define TAILQ_FIRST(head) ((head)->tqh_first) 574 575#define TAILQ_FOREACH(var, head, field) \ 576 for ((var) = TAILQ_FIRST((head)); \ 577 (var); \ 578 (var) = TAILQ_NEXT((var), field)) 579 580#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 581 for ((var) = TAILQ_FIRST((head)); \ 582 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 583 (var) = (tvar)) 584 585#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 586 for ((var) = TAILQ_LAST((head), headname); \ 587 (var); \ 588 (var) = TAILQ_PREV((var), headname, field)) 589 590#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 591 for ((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 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 603 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 604 &TAILQ_NEXT((elm), field); \ 605 else { \ 606 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 607 QMD_TRACE_HEAD(head); \ 608 } \ 609 TAILQ_NEXT((listelm), field) = (elm); \ 610 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 611 QMD_TRACE_ELEM(&(elm)->field); \ 612 QMD_TRACE_ELEM(&listelm->field); \ 613} while (0) 614 615#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 616 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 617 TAILQ_NEXT((elm), field) = (listelm); \ 618 *(listelm)->field.tqe_prev = (elm); \ 619 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 620 QMD_TRACE_ELEM(&(elm)->field); \ 621 QMD_TRACE_ELEM(&listelm->field); \ 622} while (0) 623 624#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 625 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 626 TAILQ_FIRST((head))->field.tqe_prev = \ 627 &TAILQ_NEXT((elm), field); \ 628 else \ 629 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 630 TAILQ_FIRST((head)) = (elm); \ 631 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 632 QMD_TRACE_HEAD(head); \ 633 QMD_TRACE_ELEM(&(elm)->field); \ 634} while (0) 635 636#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 637 TAILQ_NEXT((elm), field) = NULL; \ 638 (elm)->field.tqe_prev = (head)->tqh_last; \ 639 *(head)->tqh_last = (elm); \ 640 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 641 QMD_TRACE_HEAD(head); \ 642 QMD_TRACE_ELEM(&(elm)->field); \ 643} while (0) 644 645#define TAILQ_LAST(head, headname) \ 646__MISMATCH_TAGS_PUSH \ 647 (*(((struct headname *)((head)->tqh_last))->tqh_last)) \ 648__MISMATCH_TAGS_POP 649 650#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 651 652#define TAILQ_PREV(elm, headname, field) \ 653__MISMATCH_TAGS_PUSH \ 654 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) \ 655__MISMATCH_TAGS_POP 656 657#define TAILQ_REMOVE(head, elm, field) do { \ 658 if ((TAILQ_NEXT((elm), field)) != NULL) \ 659 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 660 (elm)->field.tqe_prev; \ 661 else { \ 662 (head)->tqh_last = (elm)->field.tqe_prev; \ 663 QMD_TRACE_HEAD(head); \ 664 } \ 665 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 666 TRASHIT((elm)->field.tqe_next); \ 667 TRASHIT((elm)->field.tqe_prev); \ 668 QMD_TRACE_ELEM(&(elm)->field); \ 669} while (0) 670 671/* 672 * Why did they switch to spaces for this one macro? 673 */ 674#define TAILQ_SWAP(head1, head2, type, field) \ 675__MISMATCH_TAGS_PUSH \ 676do { \ 677 struct type *swap_first = (head1)->tqh_first; \ 678 struct type **swap_last = (head1)->tqh_last; \ 679 (head1)->tqh_first = (head2)->tqh_first; \ 680 (head1)->tqh_last = (head2)->tqh_last; \ 681 (head2)->tqh_first = swap_first; \ 682 (head2)->tqh_last = swap_last; \ 683 if ((swap_first = (head1)->tqh_first) != NULL) \ 684 swap_first->field.tqe_prev = &(head1)->tqh_first; \ 685 else \ 686 (head1)->tqh_last = &(head1)->tqh_first; \ 687 if ((swap_first = (head2)->tqh_first) != NULL) \ 688 swap_first->field.tqe_prev = &(head2)->tqh_first; \ 689 else \ 690 (head2)->tqh_last = &(head2)->tqh_first; \ 691} while (0) \ 692__MISMATCH_TAGS_POP 693 694/* 695 * Circular queue definitions. 696 */ 697#define CIRCLEQ_HEAD(name, type) \ 698__MISMATCH_TAGS_PUSH \ 699struct name { \ 700 struct type *cqh_first; /* first element */ \ 701 struct type *cqh_last; /* last element */ \ 702} \ 703__MISMATCH_TAGS_POP 704 705#define CIRCLEQ_ENTRY(type) \ 706__MISMATCH_TAGS_PUSH \ 707struct { \ 708 struct type *cqe_next; /* next element */ \ 709 struct type *cqe_prev; /* previous element */ \ 710} \ 711__MISMATCH_TAGS_POP 712 713/* 714 * Circular queue functions. 715 */ 716#define CIRCLEQ_EMPTY(head) ((head)->cqh_first == (void *)(head)) 717 718#define CIRCLEQ_FIRST(head) ((head)->cqh_first) 719 720#define CIRCLEQ_FOREACH(var, head, field) \ 721 for((var) = (head)->cqh_first; \ 722 (var) != (void *)(head); \ 723 (var) = (var)->field.cqe_next) 724 725#define CIRCLEQ_INIT(head) do { \ 726 (head)->cqh_first = (void *)(head); \ 727 (head)->cqh_last = (void *)(head); \ 728} while (0) 729 730#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 731 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 732 (elm)->field.cqe_prev = (listelm); \ 733 if ((listelm)->field.cqe_next == (void *)(head)) \ 734 (head)->cqh_last = (elm); \ 735 else \ 736 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 737 (listelm)->field.cqe_next = (elm); \ 738} while (0) 739 740#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 741 (elm)->field.cqe_next = (listelm); \ 742 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 743 if ((listelm)->field.cqe_prev == (void *)(head)) \ 744 (head)->cqh_first = (elm); \ 745 else \ 746 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 747 (listelm)->field.cqe_prev = (elm); \ 748} while (0) 749 750#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 751 (elm)->field.cqe_next = (head)->cqh_first; \ 752 (elm)->field.cqe_prev = (void *)(head); \ 753 if ((head)->cqh_last == (void *)(head)) \ 754 (head)->cqh_last = (elm); \ 755 else \ 756 (head)->cqh_first->field.cqe_prev = (elm); \ 757 (head)->cqh_first = (elm); \ 758} while (0) 759 760#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 761 (elm)->field.cqe_next = (void *)(head); \ 762 (elm)->field.cqe_prev = (head)->cqh_last; \ 763 if ((head)->cqh_first == (void *)(head)) \ 764 (head)->cqh_first = (elm); \ 765 else \ 766 (head)->cqh_last->field.cqe_next = (elm); \ 767 (head)->cqh_last = (elm); \ 768} while (0) 769 770#define CIRCLEQ_LAST(head) ((head)->cqh_last) 771 772#define CIRCLEQ_NEXT(elm,field) ((elm)->field.cqe_next) 773 774#define CIRCLEQ_PREV(elm,field) ((elm)->field.cqe_prev) 775 776#define CIRCLEQ_REMOVE(head, elm, field) do { \ 777 if ((elm)->field.cqe_next == (void *)(head)) \ 778 (head)->cqh_last = (elm)->field.cqe_prev; \ 779 else \ 780 (elm)->field.cqe_next->field.cqe_prev = \ 781 (elm)->field.cqe_prev; \ 782 if ((elm)->field.cqe_prev == (void *)(head)) \ 783 (head)->cqh_first = (elm)->field.cqe_next; \ 784 else \ 785 (elm)->field.cqe_prev->field.cqe_next = \ 786 (elm)->field.cqe_next; \ 787} while (0) 788 789#ifdef _KERNEL 790 791#if NOTFB31 792 793/* 794 * XXX insque() and remque() are an old way of handling certain queues. 795 * They bogusly assumes that all queue heads look alike. 796 */ 797 798struct quehead { 799 struct quehead *qh_link; 800 struct quehead *qh_rlink; 801}; 802 803#ifdef __GNUC__ 804 805static __inline void 806insque(void *a, void *b) 807{ 808 struct quehead *element = (struct quehead *)a, 809 *head = (struct quehead *)b; 810 811 element->qh_link = head->qh_link; 812 element->qh_rlink = head; 813 head->qh_link = element; 814 element->qh_link->qh_rlink = element; 815} 816 817static __inline void 818remque(void *a) 819{ 820 struct quehead *element = (struct quehead *)a; 821 822 element->qh_link->qh_rlink = element->qh_rlink; 823 element->qh_rlink->qh_link = element->qh_link; 824 element->qh_rlink = 0; 825} 826 827#else /* !__GNUC__ */ 828 829void insque(void *a, void *b); 830void remque(void *a); 831 832#endif /* __GNUC__ */ 833 834#endif 835#endif /* _KERNEL */ 836 837#endif /* !_SYS_QUEUE_H_ */ 838