sys-queue.h revision 181097
1/* $OpenBSD: queue.h,v 1.25 2004/04/08 16:08:21 henning Exp $ */ 2/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */ 3 4/* 5 * Copyright (c) 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)queue.h 8.5 (Berkeley) 8/20/94 33 */ 34 35/* OPENBSD ORIGINAL: sys/sys/queue.h */ 36 37#ifndef _FAKE_QUEUE_H_ 38#define _FAKE_QUEUE_H_ 39 40/* 41 * Require for OS/X and other platforms that have old/broken/incomplete 42 * <sys/queue.h>. 43 */ 44#undef SLIST_HEAD 45#undef SLIST_HEAD_INITIALIZER 46#undef SLIST_ENTRY 47#undef SLIST_FOREACH_PREVPTR 48#undef SLIST_FIRST 49#undef SLIST_END 50#undef SLIST_EMPTY 51#undef SLIST_NEXT 52#undef SLIST_FOREACH 53#undef SLIST_INIT 54#undef SLIST_INSERT_AFTER 55#undef SLIST_INSERT_HEAD 56#undef SLIST_REMOVE_HEAD 57#undef SLIST_REMOVE 58#undef SLIST_REMOVE_NEXT 59#undef LIST_HEAD 60#undef LIST_HEAD_INITIALIZER 61#undef LIST_ENTRY 62#undef LIST_FIRST 63#undef LIST_END 64#undef LIST_EMPTY 65#undef LIST_NEXT 66#undef LIST_FOREACH 67#undef LIST_INIT 68#undef LIST_INSERT_AFTER 69#undef LIST_INSERT_BEFORE 70#undef LIST_INSERT_HEAD 71#undef LIST_REMOVE 72#undef LIST_REPLACE 73#undef SIMPLEQ_HEAD 74#undef SIMPLEQ_HEAD_INITIALIZER 75#undef SIMPLEQ_ENTRY 76#undef SIMPLEQ_FIRST 77#undef SIMPLEQ_END 78#undef SIMPLEQ_EMPTY 79#undef SIMPLEQ_NEXT 80#undef SIMPLEQ_FOREACH 81#undef SIMPLEQ_INIT 82#undef SIMPLEQ_INSERT_HEAD 83#undef SIMPLEQ_INSERT_TAIL 84#undef SIMPLEQ_INSERT_AFTER 85#undef SIMPLEQ_REMOVE_HEAD 86#undef TAILQ_HEAD 87#undef TAILQ_HEAD_INITIALIZER 88#undef TAILQ_ENTRY 89#undef TAILQ_FIRST 90#undef TAILQ_END 91#undef TAILQ_NEXT 92#undef TAILQ_LAST 93#undef TAILQ_PREV 94#undef TAILQ_EMPTY 95#undef TAILQ_FOREACH 96#undef TAILQ_FOREACH_REVERSE 97#undef TAILQ_INIT 98#undef TAILQ_INSERT_HEAD 99#undef TAILQ_INSERT_TAIL 100#undef TAILQ_INSERT_AFTER 101#undef TAILQ_INSERT_BEFORE 102#undef TAILQ_REMOVE 103#undef TAILQ_REPLACE 104#undef CIRCLEQ_HEAD 105#undef CIRCLEQ_HEAD_INITIALIZER 106#undef CIRCLEQ_ENTRY 107#undef CIRCLEQ_FIRST 108#undef CIRCLEQ_LAST 109#undef CIRCLEQ_END 110#undef CIRCLEQ_NEXT 111#undef CIRCLEQ_PREV 112#undef CIRCLEQ_EMPTY 113#undef CIRCLEQ_FOREACH 114#undef CIRCLEQ_FOREACH_REVERSE 115#undef CIRCLEQ_INIT 116#undef CIRCLEQ_INSERT_AFTER 117#undef CIRCLEQ_INSERT_BEFORE 118#undef CIRCLEQ_INSERT_HEAD 119#undef CIRCLEQ_INSERT_TAIL 120#undef CIRCLEQ_REMOVE 121#undef CIRCLEQ_REPLACE 122 123/* 124 * This file defines five types of data structures: singly-linked lists, 125 * lists, simple queues, tail queues, and circular queues. 126 * 127 * 128 * A singly-linked list is headed by a single forward pointer. The elements 129 * are singly linked for minimum space and pointer manipulation overhead at 130 * the expense of O(n) removal for arbitrary elements. New elements can be 131 * added to the list after an existing element or at the head of the list. 132 * Elements being removed from the head of the list should use the explicit 133 * macro for this purpose for optimum efficiency. A singly-linked list may 134 * only be traversed in the forward direction. Singly-linked lists are ideal 135 * for applications with large datasets and few or no removals or for 136 * implementing a LIFO queue. 137 * 138 * A list is headed by a single forward pointer (or an array of forward 139 * pointers for a hash table header). The elements are doubly linked 140 * so that an arbitrary element can be removed without a need to 141 * traverse the list. New elements can be added to the list before 142 * or after an existing element or at the head of the list. A list 143 * may only be traversed in the forward direction. 144 * 145 * A simple queue is headed by a pair of pointers, one the head of the 146 * list and the other to the tail of the list. The elements are singly 147 * linked to save space, so elements can only be removed from the 148 * head of the list. New elements can be added to the list before or after 149 * an existing element, at the head of the list, or at the end of the 150 * list. A simple queue may only be traversed in the forward direction. 151 * 152 * A tail queue is headed by a pair of pointers, one to the head of the 153 * list and the other to the tail of the list. The elements are doubly 154 * linked so that an arbitrary element can be removed without a need to 155 * traverse the list. New elements can be added to the list before or 156 * after an existing element, at the head of the list, or at the end of 157 * the list. A tail queue may be traversed in either direction. 158 * 159 * A circle queue is headed by a pair of pointers, one to the head of the 160 * list and the other to the tail of the list. The elements are doubly 161 * linked so that an arbitrary element can be removed without a need to 162 * traverse the list. New elements can be added to the list before or after 163 * an existing element, at the head of the list, or at the end of the list. 164 * A circle queue may be traversed in either direction, but has a more 165 * complex end of list detection. 166 * 167 * For details on the use of these macros, see the queue(3) manual page. 168 */ 169 170/* 171 * Singly-linked List definitions. 172 */ 173#define SLIST_HEAD(name, type) \ 174struct name { \ 175 struct type *slh_first; /* first element */ \ 176} 177 178#define SLIST_HEAD_INITIALIZER(head) \ 179 { NULL } 180 181#define SLIST_ENTRY(type) \ 182struct { \ 183 struct type *sle_next; /* next element */ \ 184} 185 186/* 187 * Singly-linked List access methods. 188 */ 189#define SLIST_FIRST(head) ((head)->slh_first) 190#define SLIST_END(head) NULL 191#define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) 192#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 193 194#define SLIST_FOREACH(var, head, field) \ 195 for((var) = SLIST_FIRST(head); \ 196 (var) != SLIST_END(head); \ 197 (var) = SLIST_NEXT(var, field)) 198 199#define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 200 for ((varp) = &SLIST_FIRST((head)); \ 201 ((var) = *(varp)) != SLIST_END(head); \ 202 (varp) = &SLIST_NEXT((var), field)) 203 204/* 205 * Singly-linked List functions. 206 */ 207#define SLIST_INIT(head) { \ 208 SLIST_FIRST(head) = SLIST_END(head); \ 209} 210 211#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 212 (elm)->field.sle_next = (slistelm)->field.sle_next; \ 213 (slistelm)->field.sle_next = (elm); \ 214} while (0) 215 216#define SLIST_INSERT_HEAD(head, elm, field) do { \ 217 (elm)->field.sle_next = (head)->slh_first; \ 218 (head)->slh_first = (elm); \ 219} while (0) 220 221#define SLIST_REMOVE_NEXT(head, elm, field) do { \ 222 (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \ 223} while (0) 224 225#define SLIST_REMOVE_HEAD(head, field) do { \ 226 (head)->slh_first = (head)->slh_first->field.sle_next; \ 227} while (0) 228 229#define SLIST_REMOVE(head, elm, type, field) do { \ 230 if ((head)->slh_first == (elm)) { \ 231 SLIST_REMOVE_HEAD((head), field); \ 232 } \ 233 else { \ 234 struct type *curelm = (head)->slh_first; \ 235 while( curelm->field.sle_next != (elm) ) \ 236 curelm = curelm->field.sle_next; \ 237 curelm->field.sle_next = \ 238 curelm->field.sle_next->field.sle_next; \ 239 } \ 240} while (0) 241 242/* 243 * List definitions. 244 */ 245#define LIST_HEAD(name, type) \ 246struct name { \ 247 struct type *lh_first; /* first element */ \ 248} 249 250#define LIST_HEAD_INITIALIZER(head) \ 251 { NULL } 252 253#define LIST_ENTRY(type) \ 254struct { \ 255 struct type *le_next; /* next element */ \ 256 struct type **le_prev; /* address of previous next element */ \ 257} 258 259/* 260 * List access methods 261 */ 262#define LIST_FIRST(head) ((head)->lh_first) 263#define LIST_END(head) NULL 264#define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) 265#define LIST_NEXT(elm, field) ((elm)->field.le_next) 266 267#define LIST_FOREACH(var, head, field) \ 268 for((var) = LIST_FIRST(head); \ 269 (var)!= LIST_END(head); \ 270 (var) = LIST_NEXT(var, field)) 271 272/* 273 * List functions. 274 */ 275#define LIST_INIT(head) do { \ 276 LIST_FIRST(head) = LIST_END(head); \ 277} while (0) 278 279#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 280 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 281 (listelm)->field.le_next->field.le_prev = \ 282 &(elm)->field.le_next; \ 283 (listelm)->field.le_next = (elm); \ 284 (elm)->field.le_prev = &(listelm)->field.le_next; \ 285} while (0) 286 287#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 288 (elm)->field.le_prev = (listelm)->field.le_prev; \ 289 (elm)->field.le_next = (listelm); \ 290 *(listelm)->field.le_prev = (elm); \ 291 (listelm)->field.le_prev = &(elm)->field.le_next; \ 292} while (0) 293 294#define LIST_INSERT_HEAD(head, elm, field) do { \ 295 if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 296 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 297 (head)->lh_first = (elm); \ 298 (elm)->field.le_prev = &(head)->lh_first; \ 299} while (0) 300 301#define LIST_REMOVE(elm, field) do { \ 302 if ((elm)->field.le_next != NULL) \ 303 (elm)->field.le_next->field.le_prev = \ 304 (elm)->field.le_prev; \ 305 *(elm)->field.le_prev = (elm)->field.le_next; \ 306} while (0) 307 308#define LIST_REPLACE(elm, elm2, field) do { \ 309 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ 310 (elm2)->field.le_next->field.le_prev = \ 311 &(elm2)->field.le_next; \ 312 (elm2)->field.le_prev = (elm)->field.le_prev; \ 313 *(elm2)->field.le_prev = (elm2); \ 314} while (0) 315 316/* 317 * Simple queue definitions. 318 */ 319#define SIMPLEQ_HEAD(name, type) \ 320struct name { \ 321 struct type *sqh_first; /* first element */ \ 322 struct type **sqh_last; /* addr of last next element */ \ 323} 324 325#define SIMPLEQ_HEAD_INITIALIZER(head) \ 326 { NULL, &(head).sqh_first } 327 328#define SIMPLEQ_ENTRY(type) \ 329struct { \ 330 struct type *sqe_next; /* next element */ \ 331} 332 333/* 334 * Simple queue access methods. 335 */ 336#define SIMPLEQ_FIRST(head) ((head)->sqh_first) 337#define SIMPLEQ_END(head) NULL 338#define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) 339#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) 340 341#define SIMPLEQ_FOREACH(var, head, field) \ 342 for((var) = SIMPLEQ_FIRST(head); \ 343 (var) != SIMPLEQ_END(head); \ 344 (var) = SIMPLEQ_NEXT(var, field)) 345 346/* 347 * Simple queue functions. 348 */ 349#define SIMPLEQ_INIT(head) do { \ 350 (head)->sqh_first = NULL; \ 351 (head)->sqh_last = &(head)->sqh_first; \ 352} while (0) 353 354#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ 355 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ 356 (head)->sqh_last = &(elm)->field.sqe_next; \ 357 (head)->sqh_first = (elm); \ 358} while (0) 359 360#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ 361 (elm)->field.sqe_next = NULL; \ 362 *(head)->sqh_last = (elm); \ 363 (head)->sqh_last = &(elm)->field.sqe_next; \ 364} while (0) 365 366#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 367 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ 368 (head)->sqh_last = &(elm)->field.sqe_next; \ 369 (listelm)->field.sqe_next = (elm); \ 370} while (0) 371 372#define SIMPLEQ_REMOVE_HEAD(head, elm, field) do { \ 373 if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) \ 374 (head)->sqh_last = &(head)->sqh_first; \ 375} while (0) 376 377/* 378 * Tail queue definitions. 379 */ 380#define TAILQ_HEAD(name, type) \ 381struct name { \ 382 struct type *tqh_first; /* first element */ \ 383 struct type **tqh_last; /* addr of last next element */ \ 384} 385 386#define TAILQ_HEAD_INITIALIZER(head) \ 387 { NULL, &(head).tqh_first } 388 389#define TAILQ_ENTRY(type) \ 390struct { \ 391 struct type *tqe_next; /* next element */ \ 392 struct type **tqe_prev; /* address of previous next element */ \ 393} 394 395/* 396 * tail queue access methods 397 */ 398#define TAILQ_FIRST(head) ((head)->tqh_first) 399#define TAILQ_END(head) NULL 400#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 401#define TAILQ_LAST(head, headname) \ 402 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 403/* XXX */ 404#define TAILQ_PREV(elm, headname, field) \ 405 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 406#define TAILQ_EMPTY(head) \ 407 (TAILQ_FIRST(head) == TAILQ_END(head)) 408 409#define TAILQ_FOREACH(var, head, field) \ 410 for((var) = TAILQ_FIRST(head); \ 411 (var) != TAILQ_END(head); \ 412 (var) = TAILQ_NEXT(var, field)) 413 414#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 415 for((var) = TAILQ_LAST(head, headname); \ 416 (var) != TAILQ_END(head); \ 417 (var) = TAILQ_PREV(var, headname, field)) 418 419/* 420 * Tail queue functions. 421 */ 422#define TAILQ_INIT(head) do { \ 423 (head)->tqh_first = NULL; \ 424 (head)->tqh_last = &(head)->tqh_first; \ 425} while (0) 426 427#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 428 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 429 (head)->tqh_first->field.tqe_prev = \ 430 &(elm)->field.tqe_next; \ 431 else \ 432 (head)->tqh_last = &(elm)->field.tqe_next; \ 433 (head)->tqh_first = (elm); \ 434 (elm)->field.tqe_prev = &(head)->tqh_first; \ 435} while (0) 436 437#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 438 (elm)->field.tqe_next = NULL; \ 439 (elm)->field.tqe_prev = (head)->tqh_last; \ 440 *(head)->tqh_last = (elm); \ 441 (head)->tqh_last = &(elm)->field.tqe_next; \ 442} while (0) 443 444#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 445 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 446 (elm)->field.tqe_next->field.tqe_prev = \ 447 &(elm)->field.tqe_next; \ 448 else \ 449 (head)->tqh_last = &(elm)->field.tqe_next; \ 450 (listelm)->field.tqe_next = (elm); \ 451 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 452} while (0) 453 454#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 455 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 456 (elm)->field.tqe_next = (listelm); \ 457 *(listelm)->field.tqe_prev = (elm); \ 458 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ 459} while (0) 460 461#define TAILQ_REMOVE(head, elm, field) do { \ 462 if (((elm)->field.tqe_next) != NULL) \ 463 (elm)->field.tqe_next->field.tqe_prev = \ 464 (elm)->field.tqe_prev; \ 465 else \ 466 (head)->tqh_last = (elm)->field.tqe_prev; \ 467 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 468} while (0) 469 470#define TAILQ_REPLACE(head, elm, elm2, field) do { \ 471 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ 472 (elm2)->field.tqe_next->field.tqe_prev = \ 473 &(elm2)->field.tqe_next; \ 474 else \ 475 (head)->tqh_last = &(elm2)->field.tqe_next; \ 476 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 477 *(elm2)->field.tqe_prev = (elm2); \ 478} while (0) 479 480/* 481 * Circular queue definitions. 482 */ 483#define CIRCLEQ_HEAD(name, type) \ 484struct name { \ 485 struct type *cqh_first; /* first element */ \ 486 struct type *cqh_last; /* last element */ \ 487} 488 489#define CIRCLEQ_HEAD_INITIALIZER(head) \ 490 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } 491 492#define CIRCLEQ_ENTRY(type) \ 493struct { \ 494 struct type *cqe_next; /* next element */ \ 495 struct type *cqe_prev; /* previous element */ \ 496} 497 498/* 499 * Circular queue access methods 500 */ 501#define CIRCLEQ_FIRST(head) ((head)->cqh_first) 502#define CIRCLEQ_LAST(head) ((head)->cqh_last) 503#define CIRCLEQ_END(head) ((void *)(head)) 504#define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) 505#define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) 506#define CIRCLEQ_EMPTY(head) \ 507 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head)) 508 509#define CIRCLEQ_FOREACH(var, head, field) \ 510 for((var) = CIRCLEQ_FIRST(head); \ 511 (var) != CIRCLEQ_END(head); \ 512 (var) = CIRCLEQ_NEXT(var, field)) 513 514#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ 515 for((var) = CIRCLEQ_LAST(head); \ 516 (var) != CIRCLEQ_END(head); \ 517 (var) = CIRCLEQ_PREV(var, field)) 518 519/* 520 * Circular queue functions. 521 */ 522#define CIRCLEQ_INIT(head) do { \ 523 (head)->cqh_first = CIRCLEQ_END(head); \ 524 (head)->cqh_last = CIRCLEQ_END(head); \ 525} while (0) 526 527#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 528 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 529 (elm)->field.cqe_prev = (listelm); \ 530 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \ 531 (head)->cqh_last = (elm); \ 532 else \ 533 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 534 (listelm)->field.cqe_next = (elm); \ 535} while (0) 536 537#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 538 (elm)->field.cqe_next = (listelm); \ 539 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 540 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \ 541 (head)->cqh_first = (elm); \ 542 else \ 543 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 544 (listelm)->field.cqe_prev = (elm); \ 545} while (0) 546 547#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 548 (elm)->field.cqe_next = (head)->cqh_first; \ 549 (elm)->field.cqe_prev = CIRCLEQ_END(head); \ 550 if ((head)->cqh_last == CIRCLEQ_END(head)) \ 551 (head)->cqh_last = (elm); \ 552 else \ 553 (head)->cqh_first->field.cqe_prev = (elm); \ 554 (head)->cqh_first = (elm); \ 555} while (0) 556 557#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 558 (elm)->field.cqe_next = CIRCLEQ_END(head); \ 559 (elm)->field.cqe_prev = (head)->cqh_last; \ 560 if ((head)->cqh_first == CIRCLEQ_END(head)) \ 561 (head)->cqh_first = (elm); \ 562 else \ 563 (head)->cqh_last->field.cqe_next = (elm); \ 564 (head)->cqh_last = (elm); \ 565} while (0) 566 567#define CIRCLEQ_REMOVE(head, elm, field) do { \ 568 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \ 569 (head)->cqh_last = (elm)->field.cqe_prev; \ 570 else \ 571 (elm)->field.cqe_next->field.cqe_prev = \ 572 (elm)->field.cqe_prev; \ 573 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \ 574 (head)->cqh_first = (elm)->field.cqe_next; \ 575 else \ 576 (elm)->field.cqe_prev->field.cqe_next = \ 577 (elm)->field.cqe_next; \ 578} while (0) 579 580#define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \ 581 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \ 582 CIRCLEQ_END(head)) \ 583 (head).cqh_last = (elm2); \ 584 else \ 585 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \ 586 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \ 587 CIRCLEQ_END(head)) \ 588 (head).cqh_first = (elm2); \ 589 else \ 590 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \ 591} while (0) 592 593#endif /* !_FAKE_QUEUE_H_ */ 594