queue.h revision 126891
1129198Scognet/* 2129198Scognet * Copyright (c) 1991, 1993 3139735Simp * The Regents of the University of California. All rights reserved. 4129198Scognet * 5129198Scognet * Redistribution and use in source and binary forms, with or without 6129198Scognet * modification, are permitted provided that the following conditions 7129198Scognet * are met: 8129198Scognet * 1. Redistributions of source code must retain the above copyright 9129198Scognet * notice, this list of conditions and the following disclaimer. 10129198Scognet * 2. Redistributions in binary form must reproduce the above copyright 11129198Scognet * notice, this list of conditions and the following disclaimer in the 12129198Scognet * documentation and/or other materials provided with the distribution. 13129198Scognet * 3. All advertising materials mentioning features or use of this software 14129198Scognet * must display the following acknowledgement: 15129198Scognet * This product includes software developed by the University of 16129198Scognet * California, Berkeley and its contributors. 17129198Scognet * 4. Neither the name of the University nor the names of its contributors 18129198Scognet * may be used to endorse or promote products derived from this software 19129198Scognet * without specific prior written permission. 20129198Scognet * 21129198Scognet * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22129198Scognet * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23129198Scognet * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24129198Scognet * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25129198Scognet * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26129198Scognet * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27129198Scognet * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28129198Scognet * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29129198Scognet * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30129198Scognet * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31129198Scognet * SUCH DAMAGE. 32129198Scognet * 33129198Scognet * @(#)queue.h 8.5 (Berkeley) 8/20/94 34129198Scognet * $FreeBSD: head/sys/sys/queue.h 126891 2004-03-12 21:45:33Z trhodes $ 35129198Scognet */ 36129198Scognet 37129198Scognet#ifndef _SYS_QUEUE_H_ 38129198Scognet#define _SYS_QUEUE_H_ 39129198Scognet 40129198Scognet#include <sys/cdefs.h> 41129198Scognet 42129198Scognet/* 43129198Scognet * This file defines four types of data structures: singly-linked lists, 44129198Scognet * singly-linked tail queues, lists and tail queues. 45129198Scognet * 46129198Scognet * A singly-linked list is headed by a single forward pointer. The elements 47129198Scognet * are singly linked for minimum space and pointer manipulation overhead at 48129198Scognet * the expense of O(n) removal for arbitrary elements. New elements can be 49129198Scognet * added to the list after an existing element or at the head of the list. 50129198Scognet * Elements being removed from the head of the list should use the explicit 51129198Scognet * macro for this purpose for optimum efficiency. A singly-linked list may 52137463Scognet * only be traversed in the forward direction. Singly-linked lists are ideal 53129198Scognet * for applications with large datasets and few or no removals or for 54129198Scognet * implementing a LIFO queue. 55129198Scognet * 56129198Scognet * A singly-linked tail queue is headed by a pair of pointers, one to the 57137463Scognet * head of the list and the other to the tail of the list. The elements are 58129198Scognet * singly linked for minimum space and pointer manipulation overhead at the 59129198Scognet * expense of O(n) removal for arbitrary elements. New elements can be added 60129198Scognet * to the list after an existing element, at the head of the list, or at the 61129198Scognet * end of the list. Elements being removed from the head of the tail queue 62137463Scognet * should use the explicit macro for this purpose for optimum efficiency. 63129198Scognet * A singly-linked tail queue may only be traversed in the forward direction. 64129198Scognet * Singly-linked tail queues are ideal for applications with large datasets 65129198Scognet * and few or no removals or for implementing a FIFO queue. 66129198Scognet * 67129198Scognet * A list is headed by a single forward pointer (or an array of forward 68129198Scognet * pointers for a hash table header). The elements are doubly linked 69129198Scognet * so that an arbitrary element can be removed without a need to 70137463Scognet * traverse the list. New elements can be added to the list before 71129198Scognet * or after an existing element or at the head of the list. A list 72129198Scognet * may only be traversed in the forward direction. 73129198Scognet * 74129198Scognet * A tail queue is headed by a pair of pointers, one to the head of the 75137463Scognet * list and the other to the tail of the list. The elements are doubly 76129198Scognet * linked so that an arbitrary element can be removed without a need to 77129198Scognet * traverse the list. New elements can be added to the list before or 78129198Scognet * after an existing element, at the head of the list, or at the end of 79129198Scognet * the list. A tail queue may be traversed in either direction. 80137463Scognet * 81129198Scognet * For details on the use of these macros, see the queue(3) manual page. 82129198Scognet * 83129198Scognet * 84129198Scognet * SLIST LIST STAILQ TAILQ 85129198Scognet * _HEAD + + + + 86129198Scognet * _HEAD_INITIALIZER + + + + 87129198Scognet * _ENTRY + + + + 88129198Scognet * _INIT + + + + 89129198Scognet * _EMPTY + + + + 90129198Scognet * _FIRST + + + + 91137463Scognet * _NEXT + + + + 92129198Scognet * _PREV - - - + 93129198Scognet * _LAST - - + + 94129198Scognet * _FOREACH + + + + 95129198Scognet * _FOREACH_SAFE + + + + 96129198Scognet * _FOREACH_REVERSE - - - + 97129198Scognet * _FOREACH_REVERSE_SAFE - - - + 98137463Scognet * _INSERT_HEAD + + + + 99129198Scognet * _INSERT_BEFORE - + - + 100129198Scognet * _INSERT_AFTER + + + + 101129198Scognet * _INSERT_TAIL - - + + 102129198Scognet * _CONCAT - - + + 103129198Scognet * _REMOVE_HEAD + - + - 104129198Scognet * _REMOVE + + + + 105129198Scognet * 106137463Scognet */ 107129198Scognet#define QUEUE_MACRO_DEBUG 0 108129198Scognet#if QUEUE_MACRO_DEBUG 109129198Scognet/* Store the last 2 places the queue element or head was altered */ 110129198Scognetstruct qm_trace { 111129198Scognet char * lastfile; 112129198Scognet int lastline; 113137463Scognet char * prevfile; 114129198Scognet int prevline; 115129198Scognet}; 116129198Scognet 117129198Scognet#define TRACEBUF struct qm_trace trace; 118129198Scognet#define TRASHIT(x) do {(x) = (void *)-1;} while (0) 119129198Scognet 120129198Scognet#define QMD_TRACE_HEAD(head) do { \ 121137463Scognet (head)->trace.prevline = (head)->trace.lastline; \ 122129198Scognet (head)->trace.prevfile = (head)->trace.lastfile; \ 123129198Scognet (head)->trace.lastline = __LINE__; \ 124129198Scognet (head)->trace.lastfile = __FILE__; \ 125129198Scognet} while (0) 126129198Scognet 127129198Scognet#define QMD_TRACE_ELEM(elem) do { \ 128137463Scognet (elem)->trace.prevline = (elem)->trace.lastline; \ 129129198Scognet (elem)->trace.prevfile = (elem)->trace.lastfile; \ 130129198Scognet (elem)->trace.lastline = __LINE__; \ 131129198Scognet (elem)->trace.lastfile = __FILE__; \ 132129198Scognet} while (0) 133129198Scognet 134129198Scognet#else 135129198Scognet#define QMD_TRACE_ELEM(elem) 136129198Scognet#define QMD_TRACE_HEAD(head) 137129198Scognet#define TRACEBUF 138129198Scognet#define TRASHIT(x) 139137463Scognet#endif /* QUEUE_MACRO_DEBUG */ 140129198Scognet 141129198Scognet/* 142129198Scognet * Singly-linked List declarations. 143129198Scognet */ 144129198Scognet#define SLIST_HEAD(name, type) \ 145129198Scognetstruct name { \ 146137463Scognet struct type *slh_first; /* first element */ \ 147129198Scognet} 148129198Scognet 149129198Scognet#define SLIST_HEAD_INITIALIZER(head) \ 150129198Scognet { NULL } 151129198Scognet 152129198Scognet#define SLIST_ENTRY(type) \ 153129198Scognetstruct { \ 154137463Scognet struct type *sle_next; /* next element */ \ 155129198Scognet} 156129198Scognet 157129198Scognet/* 158129198Scognet * Singly-linked List functions. 159129198Scognet */ 160129198Scognet#define SLIST_EMPTY(head) ((head)->slh_first == NULL) 161137463Scognet 162129198Scognet#define SLIST_FIRST(head) ((head)->slh_first) 163129198Scognet 164129198Scognet#define SLIST_FOREACH(var, head, field) \ 165129198Scognet for ((var) = SLIST_FIRST((head)); \ 166129198Scognet (var); \ 167129198Scognet (var) = SLIST_NEXT((var), field)) 168129198Scognet 169137463Scognet#define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 170129198Scognet for ((var) = SLIST_FIRST((head)); \ 171129198Scognet (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 172129198Scognet (var) = (tvar)) 173129198Scognet 174129198Scognet#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 175129198Scognet for ((varp) = &SLIST_FIRST((head)); \ 176137463Scognet ((var) = *(varp)) != NULL; \ 177129198Scognet (varp) = &SLIST_NEXT((var), field)) 178129198Scognet 179129198Scognet#define SLIST_INIT(head) do { \ 180129198Scognet SLIST_FIRST((head)) = NULL; \ 181129198Scognet} while (0) 182129198Scognet 183129198Scognet#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 184129198Scognet SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 185129198Scognet SLIST_NEXT((slistelm), field) = (elm); \ 186129198Scognet} while (0) 187137463Scognet 188129198Scognet#define SLIST_INSERT_HEAD(head, elm, field) do { \ 189129198Scognet SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 190129198Scognet SLIST_FIRST((head)) = (elm); \ 191129198Scognet} while (0) 192129198Scognet 193129198Scognet#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 194137463Scognet 195129198Scognet#define SLIST_REMOVE(head, elm, type, field) do { \ 196129198Scognet if (SLIST_FIRST((head)) == (elm)) { \ 197129198Scognet SLIST_REMOVE_HEAD((head), field); \ 198129198Scognet } \ 199129198Scognet else { \ 200129198Scognet struct type *curelm = SLIST_FIRST((head)); \ 201129198Scognet while (SLIST_NEXT(curelm, field) != (elm)) \ 202137463Scognet curelm = SLIST_NEXT(curelm, field); \ 203129198Scognet SLIST_NEXT(curelm, field) = \ 204129198Scognet SLIST_NEXT(SLIST_NEXT(curelm, field), field); \ 205129198Scognet } \ 206129198Scognet} while (0) 207129198Scognet 208129198Scognet#define SLIST_REMOVE_HEAD(head, field) do { \ 209137463Scognet SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 210129198Scognet} while (0) 211129198Scognet 212129198Scognet/* 213129198Scognet * Singly-linked Tail queue declarations. 214129198Scognet */ 215129198Scognet#define STAILQ_HEAD(name, type) \ 216129198Scognetstruct name { \ 217137463Scognet struct type *stqh_first;/* first element */ \ 218129198Scognet struct type **stqh_last;/* addr of last next element */ \ 219129198Scognet} 220129198Scognet 221129198Scognet#define STAILQ_HEAD_INITIALIZER(head) \ 222129198Scognet { NULL, &(head).stqh_first } 223129198Scognet 224137463Scognet#define STAILQ_ENTRY(type) \ 225129198Scognetstruct { \ 226129198Scognet struct type *stqe_next; /* next element */ \ 227129198Scognet} 228129198Scognet 229129198Scognet/* 230129198Scognet * Singly-linked Tail queue functions. 231129198Scognet */ 232129198Scognet#define STAILQ_CONCAT(head1, head2) do { \ 233129198Scognet if (!STAILQ_EMPTY((head2))) { \ 234129198Scognet *(head1)->stqh_last = (head2)->stqh_first; \ 235137463Scognet (head1)->stqh_last = (head2)->stqh_last; \ 236129198Scognet STAILQ_INIT((head2)); \ 237129198Scognet } \ 238129198Scognet} while (0) 239129198Scognet 240129198Scognet#define STAILQ_EMPTY(head) ((head)->stqh_first == NULL) 241129198Scognet 242137463Scognet#define STAILQ_FIRST(head) ((head)->stqh_first) 243129198Scognet 244129198Scognet#define STAILQ_FOREACH(var, head, field) \ 245129198Scognet for((var) = STAILQ_FIRST((head)); \ 246129198Scognet (var); \ 247129198Scognet (var) = STAILQ_NEXT((var), field)) 248129198Scognet 249129198Scognet 250137463Scognet#define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 251129198Scognet for ((var) = STAILQ_FIRST((head)); \ 252129198Scognet (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 253129198Scognet (var) = (tvar)) 254129198Scognet 255129198Scognet#define STAILQ_INIT(head) do { \ 256129198Scognet STAILQ_FIRST((head)) = NULL; \ 257137463Scognet (head)->stqh_last = &STAILQ_FIRST((head)); \ 258129198Scognet} while (0) 259129198Scognet 260129198Scognet#define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 261129198Scognet if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 262129198Scognet (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 263129198Scognet STAILQ_NEXT((tqelm), field) = (elm); \ 264129198Scognet} while (0) 265137463Scognet 266129198Scognet#define STAILQ_INSERT_HEAD(head, elm, field) do { \ 267129198Scognet if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 268129198Scognet (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 269129198Scognet STAILQ_FIRST((head)) = (elm); \ 270129198Scognet} while (0) 271129198Scognet 272137463Scognet#define STAILQ_INSERT_TAIL(head, elm, field) do { \ 273129198Scognet STAILQ_NEXT((elm), field) = NULL; \ 274129198Scognet *(head)->stqh_last = (elm); \ 275129198Scognet (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 276129198Scognet} while (0) 277129198Scognet 278129198Scognet#define STAILQ_LAST(head, type, field) \ 279129198Scognet (STAILQ_EMPTY((head)) ? \ 280129198Scognet NULL : \ 281129198Scognet ((struct type *) \ 282129198Scognet ((char *)((head)->stqh_last) - __offsetof(struct type, field)))) 283137463Scognet 284129198Scognet#define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 285129198Scognet 286129198Scognet#define STAILQ_REMOVE(head, elm, type, field) do { \ 287129198Scognet if (STAILQ_FIRST((head)) == (elm)) { \ 288129198Scognet STAILQ_REMOVE_HEAD((head), field); \ 289137463Scognet } \ 290129198Scognet else { \ 291129198Scognet struct type *curelm = STAILQ_FIRST((head)); \ 292129198Scognet while (STAILQ_NEXT(curelm, field) != (elm)) \ 293129198Scognet curelm = STAILQ_NEXT(curelm, field); \ 294129198Scognet if ((STAILQ_NEXT(curelm, field) = \ 295129198Scognet STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\ 296129198Scognet (head)->stqh_last = &STAILQ_NEXT((curelm), field);\ 297137463Scognet } \ 298129198Scognet} while (0) 299129198Scognet 300129198Scognet#define STAILQ_REMOVE_HEAD(head, field) do { \ 301129198Scognet if ((STAILQ_FIRST((head)) = \ 302129198Scognet STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 303137463Scognet (head)->stqh_last = &STAILQ_FIRST((head)); \ 304129198Scognet} while (0) 305129198Scognet 306129198Scognet#define STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do { \ 307129198Scognet if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL) \ 308129198Scognet (head)->stqh_last = &STAILQ_FIRST((head)); \ 309129198Scognet} while (0) 310129198Scognet 311137463Scognet/* 312129198Scognet * List declarations. 313129198Scognet */ 314129198Scognet#define LIST_HEAD(name, type) \ 315129198Scognetstruct name { \ 316129198Scognet struct type *lh_first; /* first element */ \ 317137463Scognet} 318129198Scognet 319129198Scognet#define LIST_HEAD_INITIALIZER(head) \ 320129198Scognet { NULL } 321129198Scognet 322129198Scognet#define LIST_ENTRY(type) \ 323129198Scognetstruct { \ 324129198Scognet struct type *le_next; /* next element */ \ 325129198Scognet struct type **le_prev; /* address of previous next element */ \ 326129198Scognet} 327129198Scognet 328129198Scognet/* 329129198Scognet * List functions. 330137463Scognet */ 331129198Scognet 332129198Scognet#define LIST_EMPTY(head) ((head)->lh_first == NULL) 333129198Scognet 334129198Scognet#define LIST_FIRST(head) ((head)->lh_first) 335129198Scognet 336129198Scognet#define LIST_FOREACH(var, head, field) \ 337129198Scognet for ((var) = LIST_FIRST((head)); \ 338129198Scognet (var); \ 339129198Scognet (var) = LIST_NEXT((var), field)) 340137463Scognet 341129198Scognet#define LIST_FOREACH_SAFE(var, head, field, tvar) \ 342129198Scognet for ((var) = LIST_FIRST((head)); \ 343129198Scognet (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 344129198Scognet (var) = (tvar)) 345129198Scognet 346129198Scognet#define LIST_INIT(head) do { \ 347129198Scognet LIST_FIRST((head)) = NULL; \ 348129198Scognet} while (0) 349129198Scognet 350129198Scognet#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 351129198Scognet if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 352137463Scognet LIST_NEXT((listelm), field)->field.le_prev = \ 353129198Scognet &LIST_NEXT((elm), field); \ 354 LIST_NEXT((listelm), field) = (elm); \ 355 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 356} while (0) 357 358#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 359 (elm)->field.le_prev = (listelm)->field.le_prev; \ 360 LIST_NEXT((elm), field) = (listelm); \ 361 *(listelm)->field.le_prev = (elm); \ 362 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 363} while (0) 364 365#define LIST_INSERT_HEAD(head, elm, field) do { \ 366 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 367 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 368 LIST_FIRST((head)) = (elm); \ 369 (elm)->field.le_prev = &LIST_FIRST((head)); \ 370} while (0) 371 372#define LIST_NEXT(elm, field) ((elm)->field.le_next) 373 374#define LIST_REMOVE(elm, field) do { \ 375 if (LIST_NEXT((elm), field) != NULL) \ 376 LIST_NEXT((elm), field)->field.le_prev = \ 377 (elm)->field.le_prev; \ 378 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 379} while (0) 380 381/* 382 * Tail queue declarations. 383 */ 384#define TAILQ_HEAD(name, type) \ 385struct name { \ 386 struct type *tqh_first; /* first element */ \ 387 struct type **tqh_last; /* addr of last next element */ \ 388 TRACEBUF \ 389} 390 391#define TAILQ_HEAD_INITIALIZER(head) \ 392 { NULL, &(head).tqh_first } 393 394#define TAILQ_ENTRY(type) \ 395struct { \ 396 struct type *tqe_next; /* next element */ \ 397 struct type **tqe_prev; /* address of previous next element */ \ 398 TRACEBUF \ 399} 400 401/* 402 * Tail queue functions. 403 */ 404#define TAILQ_CONCAT(head1, head2, field) do { \ 405 if (!TAILQ_EMPTY(head2)) { \ 406 *(head1)->tqh_last = (head2)->tqh_first; \ 407 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 408 (head1)->tqh_last = (head2)->tqh_last; \ 409 TAILQ_INIT((head2)); \ 410 QMD_TRACE_HEAD(head); \ 411 QMD_TRACE_HEAD(head2); \ 412 } \ 413} while (0) 414 415#define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 416 417#define TAILQ_FIRST(head) ((head)->tqh_first) 418 419#define TAILQ_FOREACH(var, head, field) \ 420 for ((var) = TAILQ_FIRST((head)); \ 421 (var); \ 422 (var) = TAILQ_NEXT((var), field)) 423 424#define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 425 for ((var) = TAILQ_FIRST((head)); \ 426 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 427 (var) = (tvar)) 428 429#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 430 for ((var) = TAILQ_LAST((head), headname); \ 431 (var); \ 432 (var) = TAILQ_PREV((var), headname, field)) 433 434#define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 435 for ((var) = TAILQ_LAST((head), headname); \ 436 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 437 (var) = (tvar)) 438 439#define TAILQ_INIT(head) do { \ 440 TAILQ_FIRST((head)) = NULL; \ 441 (head)->tqh_last = &TAILQ_FIRST((head)); \ 442 QMD_TRACE_HEAD(head); \ 443} while (0) 444 445#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 446 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 447 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 448 &TAILQ_NEXT((elm), field); \ 449 else { \ 450 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 451 QMD_TRACE_HEAD(head); \ 452 } \ 453 TAILQ_NEXT((listelm), field) = (elm); \ 454 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 455 QMD_TRACE_ELEM(&(elm)->field); \ 456 QMD_TRACE_ELEM(&listelm->field); \ 457} while (0) 458 459#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 460 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 461 TAILQ_NEXT((elm), field) = (listelm); \ 462 *(listelm)->field.tqe_prev = (elm); \ 463 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 464 QMD_TRACE_ELEM(&(elm)->field); \ 465 QMD_TRACE_ELEM(&listelm->field); \ 466} while (0) 467 468#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 469 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 470 TAILQ_FIRST((head))->field.tqe_prev = \ 471 &TAILQ_NEXT((elm), field); \ 472 else \ 473 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 474 TAILQ_FIRST((head)) = (elm); \ 475 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 476 QMD_TRACE_HEAD(head); \ 477 QMD_TRACE_ELEM(&(elm)->field); \ 478} while (0) 479 480#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 481 TAILQ_NEXT((elm), field) = NULL; \ 482 (elm)->field.tqe_prev = (head)->tqh_last; \ 483 *(head)->tqh_last = (elm); \ 484 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 485 QMD_TRACE_HEAD(head); \ 486 QMD_TRACE_ELEM(&(elm)->field); \ 487} while (0) 488 489#define TAILQ_LAST(head, headname) \ 490 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 491 492#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 493 494#define TAILQ_PREV(elm, headname, field) \ 495 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 496 497#define TAILQ_REMOVE(head, elm, field) do { \ 498 if ((TAILQ_NEXT((elm), field)) != NULL) \ 499 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 500 (elm)->field.tqe_prev; \ 501 else { \ 502 (head)->tqh_last = (elm)->field.tqe_prev; \ 503 QMD_TRACE_HEAD(head); \ 504 } \ 505 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 506 TRASHIT((elm)->field.tqe_next); \ 507 TRASHIT((elm)->field.tqe_prev); \ 508 QMD_TRACE_ELEM(&(elm)->field); \ 509} while (0) 510 511 512#ifdef _KERNEL 513 514/* 515 * XXX insque() and remque() are an old way of handling certain queues. 516 * They bogusly assumes that all queue heads look alike. 517 */ 518 519struct quehead { 520 struct quehead *qh_link; 521 struct quehead *qh_rlink; 522}; 523 524#if defined(__GNUC__) || defined(__INTEL_COMPILER) 525 526static __inline void 527insque(void *a, void *b) 528{ 529 struct quehead *element = (struct quehead *)a, 530 *head = (struct quehead *)b; 531 532 element->qh_link = head->qh_link; 533 element->qh_rlink = head; 534 head->qh_link = element; 535 element->qh_link->qh_rlink = element; 536} 537 538static __inline void 539remque(void *a) 540{ 541 struct quehead *element = (struct quehead *)a; 542 543 element->qh_link->qh_rlink = element->qh_rlink; 544 element->qh_rlink->qh_link = element->qh_link; 545 element->qh_rlink = 0; 546} 547 548#else /* !(__GNUC__ || __INTEL_COMPILER) */ 549 550void insque(void *a, void *b); 551void remque(void *a); 552 553#endif /* __GNUC__ || __INTEL_COMPILER */ 554 555#endif /* _KERNEL */ 556 557#endif /* !_SYS_QUEUE_H_ */ 558