/filesystems/unixfs/common/darwin/queue.h
C++ Header | 716 lines | 444 code | 102 blank | 170 comment | 117 complexity | 6813e680d10c0ddf323e15d5fecd04b2 MD5 | raw file
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_HEAD + - + - - 137 * _REMOVE + + + + + 138 * 139 */ 140#ifdef QUEUE_MACRO_DEBUG 141/* Store the last 2 places the queue element or head was altered */ 142struct qm_trace { 143 char * lastfile; 144 int lastline; 145 char * prevfile; 146 int prevline; 147}; 148 149#define TRACEBUF struct qm_trace trace; 150#define TRASHIT(x) do {(x) = (void *)-1;} while (0) 151 152#define QMD_TRACE_HEAD(head) do { \ 153 (head)->trace.prevline = (head)->trace.lastline; \ 154 (head)->trace.prevfile = (head)->trace.lastfile; \ 155 (head)->trace.lastline = __LINE__; \ 156 (head)->trace.lastfile = __FILE__; \ 157} while (0) 158 159#define QMD_TRACE_ELEM(elem) do { \ 160 (elem)->trace.prevline = (elem)->trace.lastline; \ 161 (elem)->trace.prevfile = (elem)->trace.lastfile; \ 162 (elem)->trace.lastline = __LINE__; \ 163 (elem)->trace.lastfile = __FILE__; \ 164} while (0) 165 166#else 167#define QMD_TRACE_ELEM(elem) 168#define QMD_TRACE_HEAD(head) 169#define TRACEBUF 170#define TRASHIT(x) 171#endif /* QUEUE_MACRO_DEBUG */ 172 173/* 174 * Singly-linked List declarations. 175 */ 176#define SLIST_HEAD(name, type) \ 177struct name { \ 178 struct type *slh_first; /* first element */ \ 179} 180 181#define SLIST_HEAD_INITIALIZER(head) \ 182 { NULL } 183 184#define SLIST_ENTRY(type) \ 185struct { \ 186 struct type *sle_next; /* next element */ \ 187} 188 189/* 190 * Singly-linked List functions. 191 */ 192#define SLIST_EMPTY(head) ((head)->slh_first == NULL) 193 194#define SLIST_FIRST(head) ((head)->slh_first) 195 196#define SLIST_FOREACH(var, head, field) \ 197 for ((var) = SLIST_FIRST((head)); \ 198 (var); \ 199 (var) = SLIST_NEXT((var), field)) 200 201#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 202 for ((var) = SLIST_FIRST((head)); \ 203 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 204 (var) = (tvar)) 205 206#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 207 for ((varp) = &SLIST_FIRST((head)); \ 208 ((var) = *(varp)) != NULL; \ 209 (varp) = &SLIST_NEXT((var), field)) 210 211#define SLIST_INIT(head) do { \ 212 SLIST_FIRST((head)) = NULL; \ 213} while (0) 214 215#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 216 SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 217 SLIST_NEXT((slistelm), field) = (elm); \ 218} while (0) 219 220#define SLIST_INSERT_HEAD(head, elm, field) do { \ 221 SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 222 SLIST_FIRST((head)) = (elm); \ 223} while (0) 224 225#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 226 227#define SLIST_REMOVE(head, elm, type, field) do { \ 228 if (SLIST_FIRST((head)) == (elm)) { \ 229 SLIST_REMOVE_HEAD((head), field); \ 230 } \ 231 else { \ 232 struct type *curelm = SLIST_FIRST((head)); \ 233 while (SLIST_NEXT(curelm, field) != (elm)) \ 234 curelm = SLIST_NEXT(curelm, field); \ 235 SLIST_NEXT(curelm, field) = \ 236 SLIST_NEXT(SLIST_NEXT(curelm, field), field); \ 237 } \ 238 TRASHIT((elm)->field.sle_next); \ 239} while (0) 240 241#define SLIST_REMOVE_HEAD(head, field) do { \ 242 SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 243} while (0) 244 245/* 246 * Singly-linked Tail queue declarations. 247 */ 248#define STAILQ_HEAD(name, type) \ 249struct name { \ 250 struct type *stqh_first;/* first element */ \ 251 struct type **stqh_last;/* addr of last next element */ \ 252} 253 254#define STAILQ_HEAD_INITIALIZER(head) \ 255 { NULL, &(head).stqh_first } 256 257#define STAILQ_ENTRY(type) \ 258struct { \ 259 struct type *stqe_next; /* next element */ \ 260} 261 262/* 263 * Singly-linked Tail queue functions. 264 */ 265#define STAILQ_CONCAT(head1, head2) do { \ 266 if (!STAILQ_EMPTY((head2))) { \ 267 *(head1)->stqh_last = (head2)->stqh_first; \ 268 (head1)->stqh_last = (head2)->stqh_last; \ 269 STAILQ_INIT((head2)); \ 270 } \ 271} while (0) 272 273#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL) 274 275#define STAILQ_FIRST(head) ((head)->stqh_first) 276 277#define STAILQ_FOREACH(var, head, field) \ 278 for((var) = STAILQ_FIRST((head)); \ 279 (var); \ 280 (var) = STAILQ_NEXT((var), field)) 281 282 283#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 284 for ((var) = STAILQ_FIRST((head)); \ 285 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 286 (var) = (tvar)) 287 288#define STAILQ_INIT(head) do { \ 289 STAILQ_FIRST((head)) = NULL; \ 290 (head)->stqh_last = &STAILQ_FIRST((head)); \ 291} while (0) 292 293#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 294 if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 295 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 296 STAILQ_NEXT((tqelm), field) = (elm); \ 297} while (0) 298 299#define STAILQ_INSERT_HEAD(head, elm, field) do { \ 300 if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 301 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 302 STAILQ_FIRST((head)) = (elm); \ 303} while (0) 304 305#define STAILQ_INSERT_TAIL(head, elm, field) do { \ 306 STAILQ_NEXT((elm), field) = NULL; \ 307 *(head)->stqh_last = (elm); \ 308 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 309} while (0) 310 311#define STAILQ_LAST(head, type, field) \ 312 (STAILQ_EMPTY((head)) ? \ 313 NULL : \ 314 ((struct type *)(void *) \ 315 ((char *)((head)->stqh_last) - __offsetof(struct type, field)))) 316 317#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 318 319#define STAILQ_REMOVE(head, elm, type, field) do { \ 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 if ((STAILQ_NEXT(curelm, field) = \ 328 STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\ 329 (head)->stqh_last = &STAILQ_NEXT((curelm), field);\ 330 } \ 331 TRASHIT((elm)->field.stqe_next); \ 332} while (0) 333 334#define STAILQ_REMOVE_HEAD(head, field) do { \ 335 if ((STAILQ_FIRST((head)) = \ 336 STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 337 (head)->stqh_last = &STAILQ_FIRST((head)); \ 338} while (0) 339 340#define STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do { \ 341 if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL) \ 342 (head)->stqh_last = &STAILQ_FIRST((head)); \ 343} while (0) 344 345/* 346 * List declarations. 347 */ 348#define LIST_HEAD(name, type) \ 349struct name { \ 350 struct type *lh_first; /* first element */ \ 351} 352 353#define LIST_HEAD_INITIALIZER(head) \ 354 { NULL } 355 356#define LIST_ENTRY(type) \ 357struct { \ 358 struct type *le_next; /* next element */ \ 359 struct type **le_prev; /* address of previous next element */ \ 360} 361 362/* 363 * List functions. 364 */ 365 366#if (defined(_KERNEL) && defined(INVARIANTS)) || defined(QUEUE_MACRO_DEBUG) 367#define QMD_LIST_CHECK_HEAD(head, field) do { \ 368 if (LIST_FIRST((head)) != NULL && \ 369 LIST_FIRST((head))->field.le_prev != \ 370 &LIST_FIRST((head))) \ 371 panic("Bad list head %p first->prev != head", (head)); \ 372} while (0) 373 374#define QMD_LIST_CHECK_NEXT(elm, field) do { \ 375 if (LIST_NEXT((elm), field) != NULL && \ 376 LIST_NEXT((elm), field)->field.le_prev != \ 377 &((elm)->field.le_next)) \ 378 panic("Bad link elm %p next->prev != elm", (elm)); \ 379} while (0) 380 381#define QMD_LIST_CHECK_PREV(elm, field) do { \ 382 if (*(elm)->field.le_prev != (elm)) \ 383 panic("Bad link elm %p prev->next != elm", (elm)); \ 384} while (0) 385#else 386#define QMD_LIST_CHECK_HEAD(head, field) 387#define QMD_LIST_CHECK_NEXT(elm, field) 388#define QMD_LIST_CHECK_PREV(elm, field) 389#endif /* (_KERNEL && INVARIANTS) || QUEUE_MACRO_DEBUG */ 390 391#define LIST_EMPTY(head) ((head)->lh_first == NULL) 392 393#define LIST_FIRST(head) ((head)->lh_first) 394 395#define LIST_FOREACH(var, head, field) \ 396 for ((var) = LIST_FIRST((head)); \ 397 (var); \ 398 (var) = LIST_NEXT((var), field)) 399 400#define LIST_FOREACH_SAFE(var, head, field, tvar) \ 401 for ((var) = LIST_FIRST((head)); \ 402 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 403 (var) = (tvar)) 404 405#define LIST_INIT(head) do { \ 406 LIST_FIRST((head)) = NULL; \ 407} while (0) 408 409#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 410 QMD_LIST_CHECK_NEXT(listelm, field); \ 411 if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 412 LIST_NEXT((listelm), field)->field.le_prev = \ 413 &LIST_NEXT((elm), field); \ 414 LIST_NEXT((listelm), field) = (elm); \ 415 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 416} while (0) 417 418#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 419 QMD_LIST_CHECK_PREV(listelm, field); \ 420 (elm)->field.le_prev = (listelm)->field.le_prev; \ 421 LIST_NEXT((elm), field) = (listelm); \ 422 *(listelm)->field.le_prev = (elm); \ 423 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 424} while (0) 425 426#define LIST_INSERT_HEAD(head, elm, field) do { \ 427 QMD_LIST_CHECK_HEAD((head), field); \ 428 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 429 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 430 LIST_FIRST((head)) = (elm); \ 431 (elm)->field.le_prev = &LIST_FIRST((head)); \ 432} while (0) 433 434#define LIST_NEXT(elm, field) ((elm)->field.le_next) 435 436#define LIST_REMOVE(elm, field) do { \ 437 QMD_LIST_CHECK_NEXT(elm, field); \ 438 QMD_LIST_CHECK_PREV(elm, field); \ 439 if (LIST_NEXT((elm), field) != NULL) \ 440 LIST_NEXT((elm), field)->field.le_prev = \ 441 (elm)->field.le_prev; \ 442 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 443 TRASHIT((elm)->field.le_next); \ 444 TRASHIT((elm)->field.le_prev); \ 445} while (0) 446 447/* 448 * Tail queue declarations. 449 */ 450#define TAILQ_HEAD(name, type) \ 451struct name { \ 452 struct type *tqh_first; /* first element */ \ 453 struct type **tqh_last; /* addr of last next element */ \ 454 TRACEBUF \ 455} 456 457#define TAILQ_HEAD_INITIALIZER(head) \ 458 { NULL, &(head).tqh_first } 459 460#define TAILQ_ENTRY(type) \ 461struct { \ 462 struct type *tqe_next; /* next element */ \ 463 struct type **tqe_prev; /* address of previous next element */ \ 464 TRACEBUF \ 465} 466 467/* 468 * Tail queue functions. 469 */ 470#define TAILQ_CONCAT(head1, head2, field) do { \ 471 if (!TAILQ_EMPTY(head2)) { \ 472 *(head1)->tqh_last = (head2)->tqh_first; \ 473 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 474 (head1)->tqh_last = (head2)->tqh_last; \ 475 TAILQ_INIT((head2)); \ 476 QMD_TRACE_HEAD(head1); \ 477 QMD_TRACE_HEAD(head2); \ 478 } \ 479} while (0) 480 481#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 482 483#define TAILQ_FIRST(head) ((head)->tqh_first) 484 485#define TAILQ_FOREACH(var, head, field) \ 486 for ((var) = TAILQ_FIRST((head)); \ 487 (var); \ 488 (var) = TAILQ_NEXT((var), field)) 489 490#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 491 for ((var) = TAILQ_FIRST((head)); \ 492 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 493 (var) = (tvar)) 494 495#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 496 for ((var) = TAILQ_LAST((head), headname); \ 497 (var); \ 498 (var) = TAILQ_PREV((var), headname, field)) 499 500#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 501 for ((var) = TAILQ_LAST((head), headname); \ 502 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 503 (var) = (tvar)) 504 505#define TAILQ_INIT(head) do { \ 506 TAILQ_FIRST((head)) = NULL; \ 507 (head)->tqh_last = &TAILQ_FIRST((head)); \ 508 QMD_TRACE_HEAD(head); \ 509} while (0) 510 511#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 512 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 513 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 514 &TAILQ_NEXT((elm), field); \ 515 else { \ 516 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 517 QMD_TRACE_HEAD(head); \ 518 } \ 519 TAILQ_NEXT((listelm), field) = (elm); \ 520 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 521 QMD_TRACE_ELEM(&(elm)->field); \ 522 QMD_TRACE_ELEM(&listelm->field); \ 523} while (0) 524 525#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 526 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 527 TAILQ_NEXT((elm), field) = (listelm); \ 528 *(listelm)->field.tqe_prev = (elm); \ 529 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 530 QMD_TRACE_ELEM(&(elm)->field); \ 531 QMD_TRACE_ELEM(&listelm->field); \ 532} while (0) 533 534#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 535 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 536 TAILQ_FIRST((head))->field.tqe_prev = \ 537 &TAILQ_NEXT((elm), field); \ 538 else \ 539 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 540 TAILQ_FIRST((head)) = (elm); \ 541 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 542 QMD_TRACE_HEAD(head); \ 543 QMD_TRACE_ELEM(&(elm)->field); \ 544} while (0) 545 546#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 547 TAILQ_NEXT((elm), field) = NULL; \ 548 (elm)->field.tqe_prev = (head)->tqh_last; \ 549 *(head)->tqh_last = (elm); \ 550 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 551 QMD_TRACE_HEAD(head); \ 552 QMD_TRACE_ELEM(&(elm)->field); \ 553} while (0) 554 555#define TAILQ_LAST(head, headname) \ 556 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 557 558#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 559 560#define TAILQ_PREV(elm, headname, field) \ 561 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 562 563#define TAILQ_REMOVE(head, elm, field) do { \ 564 if ((TAILQ_NEXT((elm), field)) != NULL) \ 565 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 566 (elm)->field.tqe_prev; \ 567 else { \ 568 (head)->tqh_last = (elm)->field.tqe_prev; \ 569 QMD_TRACE_HEAD(head); \ 570 } \ 571 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 572 TRASHIT((elm)->field.tqe_next); \ 573 TRASHIT((elm)->field.tqe_prev); \ 574 QMD_TRACE_ELEM(&(elm)->field); \ 575} while (0) 576 577/* 578 * Circular queue definitions. 579 */ 580#define CIRCLEQ_HEAD(name, type) \ 581struct name { \ 582 struct type *cqh_first; /* first element */ \ 583 struct type *cqh_last; /* last element */ \ 584} 585 586#define CIRCLEQ_ENTRY(type) \ 587struct { \ 588 struct type *cqe_next; /* next element */ \ 589 struct type *cqe_prev; /* previous element */ \ 590} 591 592/* 593 * Circular queue functions. 594 */ 595#define CIRCLEQ_EMPTY(head) ((head)->cqh_first == (void *)(head)) 596 597#define CIRCLEQ_FIRST(head) ((head)->cqh_first) 598 599#define CIRCLEQ_FOREACH(var, head, field) \ 600 for((var) = (head)->cqh_first; \ 601 (var) != (void *)(head); \ 602 (var) = (var)->field.cqe_next) 603 604#define CIRCLEQ_INIT(head) do { \ 605 (head)->cqh_first = (void *)(head); \ 606 (head)->cqh_last = (void *)(head); \ 607} while (0) 608 609#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 610 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 611 (elm)->field.cqe_prev = (listelm); \ 612 if ((listelm)->field.cqe_next == (void *)(head)) \ 613 (head)->cqh_last = (elm); \ 614 else \ 615 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 616 (listelm)->field.cqe_next = (elm); \ 617} while (0) 618 619#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 620 (elm)->field.cqe_next = (listelm); \ 621 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 622 if ((listelm)->field.cqe_prev == (void *)(head)) \ 623 (head)->cqh_first = (elm); \ 624 else \ 625 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 626 (listelm)->field.cqe_prev = (elm); \ 627} while (0) 628 629#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 630 (elm)->field.cqe_next = (head)->cqh_first; \ 631 (elm)->field.cqe_prev = (void *)(head); \ 632 if ((head)->cqh_last == (void *)(head)) \ 633 (head)->cqh_last = (elm); \ 634 else \ 635 (head)->cqh_first->field.cqe_prev = (elm); \ 636 (head)->cqh_first = (elm); \ 637} while (0) 638 639#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 640 (elm)->field.cqe_next = (void *)(head); \ 641 (elm)->field.cqe_prev = (head)->cqh_last; \ 642 if ((head)->cqh_first == (void *)(head)) \ 643 (head)->cqh_first = (elm); \ 644 else \ 645 (head)->cqh_last->field.cqe_next = (elm); \ 646 (head)->cqh_last = (elm); \ 647} while (0) 648 649#define CIRCLEQ_LAST(head) ((head)->cqh_last) 650 651#define CIRCLEQ_NEXT(elm,field) ((elm)->field.cqe_next) 652 653#define CIRCLEQ_PREV(elm,field) ((elm)->field.cqe_prev) 654 655#define CIRCLEQ_REMOVE(head, elm, field) do { \ 656 if ((elm)->field.cqe_next == (void *)(head)) \ 657 (head)->cqh_last = (elm)->field.cqe_prev; \ 658 else \ 659 (elm)->field.cqe_next->field.cqe_prev = \ 660 (elm)->field.cqe_prev; \ 661 if ((elm)->field.cqe_prev == (void *)(head)) \ 662 (head)->cqh_first = (elm)->field.cqe_next; \ 663 else \ 664 (elm)->field.cqe_prev->field.cqe_next = \ 665 (elm)->field.cqe_next; \ 666} while (0) 667 668#ifdef _KERNEL 669 670#if NOTFB31 671 672/* 673 * XXX insque() and remque() are an old way of handling certain queues. 674 * They bogusly assumes that all queue heads look alike. 675 */ 676 677struct quehead { 678 struct quehead *qh_link; 679 struct quehead *qh_rlink; 680}; 681 682#ifdef __GNUC__ 683 684static __inline void 685insque(void *a, void *b) 686{ 687 struct quehead *element = (struct quehead *)a, 688 *head = (struct quehead *)b; 689 690 element->qh_link = head->qh_link; 691 element->qh_rlink = head; 692 head->qh_link = element; 693 element->qh_link->qh_rlink = element; 694} 695 696static __inline void 697remque(void *a) 698{ 699 struct quehead *element = (struct quehead *)a; 700 701 element->qh_link->qh_rlink = element->qh_rlink; 702 element->qh_rlink->qh_link = element->qh_link; 703 element->qh_rlink = 0; 704} 705 706#else /* !__GNUC__ */ 707 708void insque(void *a, void *b); 709void remque(void *a); 710 711#endif /* __GNUC__ */ 712 713#endif 714#endif /* _KERNEL */ 715 716#endif /* !_SYS_QUEUE_H_ */