1 /* $OpenBSD: queue.h,v 1.23 2003/06/02 23:28:21 millert 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 #ifndef _FAKE_QUEUE_H_ 36 #define _FAKE_QUEUE_H_ 37 38 /* 39 * Ignore all <sys/queue.h> since older platforms have broken/incomplete 40 * <sys/queue.h> that are too hard to work around. 41 */ 42 #undef SLIST_HEAD 43 #undef SLIST_HEAD_INITIALIZER 44 #undef SLIST_ENTRY 45 #undef SLIST_FIRST 46 #undef SLIST_END 47 #undef SLIST_EMPTY 48 #undef SLIST_NEXT 49 #undef SLIST_FOREACH 50 #undef SLIST_INIT 51 #undef SLIST_INSERT_AFTER 52 #undef SLIST_INSERT_HEAD 53 #undef SLIST_REMOVE_HEAD 54 #undef SLIST_REMOVE 55 #undef LIST_HEAD 56 #undef LIST_HEAD_INITIALIZER 57 #undef LIST_ENTRY 58 #undef LIST_FIRST 59 #undef LIST_END 60 #undef LIST_EMPTY 61 #undef LIST_NEXT 62 #undef LIST_FOREACH 63 #undef LIST_INIT 64 #undef LIST_INSERT_AFTER 65 #undef LIST_INSERT_BEFORE 66 #undef LIST_INSERT_HEAD 67 #undef LIST_REMOVE 68 #undef LIST_REPLACE 69 #undef SIMPLEQ_HEAD 70 #undef SIMPLEQ_HEAD_INITIALIZER 71 #undef SIMPLEQ_ENTRY 72 #undef SIMPLEQ_FIRST 73 #undef SIMPLEQ_END 74 #undef SIMPLEQ_EMPTY 75 #undef SIMPLEQ_NEXT 76 #undef SIMPLEQ_FOREACH 77 #undef SIMPLEQ_INIT 78 #undef SIMPLEQ_INSERT_HEAD 79 #undef SIMPLEQ_INSERT_TAIL 80 #undef SIMPLEQ_INSERT_AFTER 81 #undef SIMPLEQ_REMOVE_HEAD 82 #undef TAILQ_HEAD 83 #undef TAILQ_HEAD_INITIALIZER 84 #undef TAILQ_ENTRY 85 #undef TAILQ_FIRST 86 #undef TAILQ_END 87 #undef TAILQ_NEXT 88 #undef TAILQ_LAST 89 #undef TAILQ_PREV 90 #undef TAILQ_EMPTY 91 #undef TAILQ_FOREACH 92 #undef TAILQ_FOREACH_REVERSE 93 #undef TAILQ_INIT 94 #undef TAILQ_INSERT_HEAD 95 #undef TAILQ_INSERT_TAIL 96 #undef TAILQ_INSERT_AFTER 97 #undef TAILQ_INSERT_BEFORE 98 #undef TAILQ_REMOVE 99 #undef TAILQ_REPLACE 100 #undef CIRCLEQ_HEAD 101 #undef CIRCLEQ_HEAD_INITIALIZER 102 #undef CIRCLEQ_ENTRY 103 #undef CIRCLEQ_FIRST 104 #undef CIRCLEQ_LAST 105 #undef CIRCLEQ_END 106 #undef CIRCLEQ_NEXT 107 #undef CIRCLEQ_PREV 108 #undef CIRCLEQ_EMPTY 109 #undef CIRCLEQ_FOREACH 110 #undef CIRCLEQ_FOREACH_REVERSE 111 #undef CIRCLEQ_INIT 112 #undef CIRCLEQ_INSERT_AFTER 113 #undef CIRCLEQ_INSERT_BEFORE 114 #undef CIRCLEQ_INSERT_HEAD 115 #undef CIRCLEQ_INSERT_TAIL 116 #undef CIRCLEQ_REMOVE 117 #undef CIRCLEQ_REPLACE 118 119 /* 120 * This file defines five types of data structures: singly-linked lists, 121 * lists, simple queues, tail queues, and circular queues. 122 * 123 * 124 * A singly-linked list is headed by a single forward pointer. The elements 125 * are singly linked for minimum space and pointer manipulation overhead at 126 * the expense of O(n) removal for arbitrary elements. New elements can be 127 * added to the list after an existing element or at the head of the list. 128 * Elements being removed from the head of the list should use the explicit 129 * macro for this purpose for optimum efficiency. A singly-linked list may 130 * only be traversed in the forward direction. Singly-linked lists are ideal 131 * for applications with large datasets and few or no removals or for 132 * implementing a LIFO queue. 133 * 134 * A list is headed by a single forward pointer (or an array of forward 135 * pointers for a hash table header). The elements are doubly linked 136 * so that an arbitrary element can be removed without a need to 137 * traverse the list. New elements can be added to the list before 138 * or after an existing element or at the head of the list. A list 139 * may only be traversed in the forward direction. 140 * 141 * A simple queue is headed by a pair of pointers, one the head of the 142 * list and the other to the tail of the list. The elements are singly 143 * linked to save space, so elements can only be removed from the 144 * head of the list. New elements can be added to the list before or after 145 * an existing element, at the head of the list, or at the end of the 146 * list. A simple queue may only be traversed in the forward direction. 147 * 148 * A tail queue is headed by a pair of pointers, one to the head of the 149 * list and the other to the tail of the list. The elements are doubly 150 * linked so that an arbitrary element can be removed without a need to 151 * traverse the list. New elements can be added to the list before or 152 * after an existing element, at the head of the list, or at the end of 153 * the list. A tail queue may be traversed in either direction. 154 * 155 * A circle queue is headed by a pair of pointers, one to the head of the 156 * list and the other to the tail of the list. The elements are doubly 157 * linked so that an arbitrary element can be removed without a need to 158 * traverse the list. New elements can be added to the list before or after 159 * an existing element, at the head of the list, or at the end of the list. 160 * A circle queue may be traversed in either direction, but has a more 161 * complex end of list detection. 162 * 163 * For details on the use of these macros, see the queue(3) manual page. 164 */ 165 166 /* 167 * Singly-linked List definitions. 168 */ 169 #define SLIST_HEAD(name, type) \ 170 struct name { \ 171 struct type *slh_first; /* first element */ \ 172 } 173 174 #define SLIST_HEAD_INITIALIZER(head) \ 175 { NULL } 176 177 #define SLIST_ENTRY(type) \ 178 struct { \ 179 struct type *sle_next; /* next element */ \ 180 } 181 182 /* 183 * Singly-linked List access methods. 184 */ 185 #define SLIST_FIRST(head) ((head)->slh_first) 186 #define SLIST_END(head) NULL 187 #define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) 188 #define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 189 190 #define SLIST_FOREACH(var, head, field) \ 191 for((var) = SLIST_FIRST(head); \ 192 (var) != SLIST_END(head); \ 193 (var) = SLIST_NEXT(var, field)) 194 195 /* 196 * Singly-linked List functions. 197 */ 198 #define SLIST_INIT(head) { \ 199 SLIST_FIRST(head) = SLIST_END(head); \ 200 } 201 202 #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 203 (elm)->field.sle_next = (slistelm)->field.sle_next; \ 204 (slistelm)->field.sle_next = (elm); \ 205 } while (0) 206 207 #define SLIST_INSERT_HEAD(head, elm, field) do { \ 208 (elm)->field.sle_next = (head)->slh_first; \ 209 (head)->slh_first = (elm); \ 210 } while (0) 211 212 #define SLIST_REMOVE_HEAD(head, field) do { \ 213 (head)->slh_first = (head)->slh_first->field.sle_next; \ 214 } while (0) 215 216 #define SLIST_REMOVE(head, elm, type, field) do { \ 217 if ((head)->slh_first == (elm)) { \ 218 SLIST_REMOVE_HEAD((head), field); \ 219 } \ 220 else { \ 221 struct type *curelm = (head)->slh_first; \ 222 while( curelm->field.sle_next != (elm) ) \ 223 curelm = curelm->field.sle_next; \ 224 curelm->field.sle_next = \ 225 curelm->field.sle_next->field.sle_next; \ 226 } \ 227 } while (0) 228 229 /* 230 * List definitions. 231 */ 232 #define LIST_HEAD(name, type) \ 233 struct name { \ 234 struct type *lh_first; /* first element */ \ 235 } 236 237 #define LIST_HEAD_INITIALIZER(head) \ 238 { NULL } 239 240 #define LIST_ENTRY(type) \ 241 struct { \ 242 struct type *le_next; /* next element */ \ 243 struct type **le_prev; /* address of previous next element */ \ 244 } 245 246 /* 247 * List access methods 248 */ 249 #define LIST_FIRST(head) ((head)->lh_first) 250 #define LIST_END(head) NULL 251 #define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) 252 #define LIST_NEXT(elm, field) ((elm)->field.le_next) 253 254 #define LIST_FOREACH(var, head, field) \ 255 for((var) = LIST_FIRST(head); \ 256 (var)!= LIST_END(head); \ 257 (var) = LIST_NEXT(var, field)) 258 259 /* 260 * List functions. 261 */ 262 #define LIST_INIT(head) do { \ 263 LIST_FIRST(head) = LIST_END(head); \ 264 } while (0) 265 266 #define LIST_INSERT_AFTER(listelm, elm, field) do { \ 267 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 268 (listelm)->field.le_next->field.le_prev = \ 269 &(elm)->field.le_next; \ 270 (listelm)->field.le_next = (elm); \ 271 (elm)->field.le_prev = &(listelm)->field.le_next; \ 272 } while (0) 273 274 #define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 275 (elm)->field.le_prev = (listelm)->field.le_prev; \ 276 (elm)->field.le_next = (listelm); \ 277 *(listelm)->field.le_prev = (elm); \ 278 (listelm)->field.le_prev = &(elm)->field.le_next; \ 279 } while (0) 280 281 #define LIST_INSERT_HEAD(head, elm, field) do { \ 282 if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 283 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 284 (head)->lh_first = (elm); \ 285 (elm)->field.le_prev = &(head)->lh_first; \ 286 } while (0) 287 288 #define LIST_REMOVE(elm, field) do { \ 289 if ((elm)->field.le_next != NULL) \ 290 (elm)->field.le_next->field.le_prev = \ 291 (elm)->field.le_prev; \ 292 *(elm)->field.le_prev = (elm)->field.le_next; \ 293 } while (0) 294 295 #define LIST_REPLACE(elm, elm2, field) do { \ 296 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ 297 (elm2)->field.le_next->field.le_prev = \ 298 &(elm2)->field.le_next; \ 299 (elm2)->field.le_prev = (elm)->field.le_prev; \ 300 *(elm2)->field.le_prev = (elm2); \ 301 } while (0) 302 303 /* 304 * Simple queue definitions. 305 */ 306 #define SIMPLEQ_HEAD(name, type) \ 307 struct name { \ 308 struct type *sqh_first; /* first element */ \ 309 struct type **sqh_last; /* addr of last next element */ \ 310 } 311 312 #define SIMPLEQ_HEAD_INITIALIZER(head) \ 313 { NULL, &(head).sqh_first } 314 315 #define SIMPLEQ_ENTRY(type) \ 316 struct { \ 317 struct type *sqe_next; /* next element */ \ 318 } 319 320 /* 321 * Simple queue access methods. 322 */ 323 #define SIMPLEQ_FIRST(head) ((head)->sqh_first) 324 #define SIMPLEQ_END(head) NULL 325 #define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) 326 #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) 327 328 #define SIMPLEQ_FOREACH(var, head, field) \ 329 for((var) = SIMPLEQ_FIRST(head); \ 330 (var) != SIMPLEQ_END(head); \ 331 (var) = SIMPLEQ_NEXT(var, field)) 332 333 /* 334 * Simple queue functions. 335 */ 336 #define SIMPLEQ_INIT(head) do { \ 337 (head)->sqh_first = NULL; \ 338 (head)->sqh_last = &(head)->sqh_first; \ 339 } while (0) 340 341 #define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ 342 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ 343 (head)->sqh_last = &(elm)->field.sqe_next; \ 344 (head)->sqh_first = (elm); \ 345 } while (0) 346 347 #define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ 348 (elm)->field.sqe_next = NULL; \ 349 *(head)->sqh_last = (elm); \ 350 (head)->sqh_last = &(elm)->field.sqe_next; \ 351 } while (0) 352 353 #define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 354 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ 355 (head)->sqh_last = &(elm)->field.sqe_next; \ 356 (listelm)->field.sqe_next = (elm); \ 357 } while (0) 358 359 #define SIMPLEQ_REMOVE_HEAD(head, elm, field) do { \ 360 if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) \ 361 (head)->sqh_last = &(head)->sqh_first; \ 362 } while (0) 363 364 /* 365 * Tail queue definitions. 366 */ 367 #define TAILQ_HEAD(name, type) \ 368 struct name { \ 369 struct type *tqh_first; /* first element */ \ 370 struct type **tqh_last; /* addr of last next element */ \ 371 } 372 373 #define TAILQ_HEAD_INITIALIZER(head) \ 374 { NULL, &(head).tqh_first } 375 376 #define TAILQ_ENTRY(type) \ 377 struct { \ 378 struct type *tqe_next; /* next element */ \ 379 struct type **tqe_prev; /* address of previous next element */ \ 380 } 381 382 /* 383 * tail queue access methods 384 */ 385 #define TAILQ_FIRST(head) ((head)->tqh_first) 386 #define TAILQ_END(head) NULL 387 #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 388 #define TAILQ_LAST(head, headname) \ 389 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 390 /* XXX */ 391 #define TAILQ_PREV(elm, headname, field) \ 392 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 393 #define TAILQ_EMPTY(head) \ 394 (TAILQ_FIRST(head) == TAILQ_END(head)) 395 396 #define TAILQ_FOREACH(var, head, field) \ 397 for((var) = TAILQ_FIRST(head); \ 398 (var) != TAILQ_END(head); \ 399 (var) = TAILQ_NEXT(var, field)) 400 401 #define TAILQ_FOREACH_REVERSE(var, head, field, headname) \ 402 for((var) = TAILQ_LAST(head, headname); \ 403 (var) != TAILQ_END(head); \ 404 (var) = TAILQ_PREV(var, headname, field)) 405 406 /* 407 * Tail queue functions. 408 */ 409 #define TAILQ_INIT(head) do { \ 410 (head)->tqh_first = NULL; \ 411 (head)->tqh_last = &(head)->tqh_first; \ 412 } while (0) 413 414 #define TAILQ_INSERT_HEAD(head, elm, field) do { \ 415 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 416 (head)->tqh_first->field.tqe_prev = \ 417 &(elm)->field.tqe_next; \ 418 else \ 419 (head)->tqh_last = &(elm)->field.tqe_next; \ 420 (head)->tqh_first = (elm); \ 421 (elm)->field.tqe_prev = &(head)->tqh_first; \ 422 } while (0) 423 424 #define TAILQ_INSERT_TAIL(head, elm, field) do { \ 425 (elm)->field.tqe_next = NULL; \ 426 (elm)->field.tqe_prev = (head)->tqh_last; \ 427 *(head)->tqh_last = (elm); \ 428 (head)->tqh_last = &(elm)->field.tqe_next; \ 429 } while (0) 430 431 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 432 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 433 (elm)->field.tqe_next->field.tqe_prev = \ 434 &(elm)->field.tqe_next; \ 435 else \ 436 (head)->tqh_last = &(elm)->field.tqe_next; \ 437 (listelm)->field.tqe_next = (elm); \ 438 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 439 } while (0) 440 441 #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 442 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 443 (elm)->field.tqe_next = (listelm); \ 444 *(listelm)->field.tqe_prev = (elm); \ 445 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ 446 } while (0) 447 448 #define TAILQ_REMOVE(head, elm, field) do { \ 449 if (((elm)->field.tqe_next) != NULL) \ 450 (elm)->field.tqe_next->field.tqe_prev = \ 451 (elm)->field.tqe_prev; \ 452 else \ 453 (head)->tqh_last = (elm)->field.tqe_prev; \ 454 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 455 } while (0) 456 457 #define TAILQ_REPLACE(head, elm, elm2, field) do { \ 458 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ 459 (elm2)->field.tqe_next->field.tqe_prev = \ 460 &(elm2)->field.tqe_next; \ 461 else \ 462 (head)->tqh_last = &(elm2)->field.tqe_next; \ 463 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 464 *(elm2)->field.tqe_prev = (elm2); \ 465 } while (0) 466 467 /* 468 * Circular queue definitions. 469 */ 470 #define CIRCLEQ_HEAD(name, type) \ 471 struct name { \ 472 struct type *cqh_first; /* first element */ \ 473 struct type *cqh_last; /* last element */ \ 474 } 475 476 #define CIRCLEQ_HEAD_INITIALIZER(head) \ 477 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } 478 479 #define CIRCLEQ_ENTRY(type) \ 480 struct { \ 481 struct type *cqe_next; /* next element */ \ 482 struct type *cqe_prev; /* previous element */ \ 483 } 484 485 /* 486 * Circular queue access methods 487 */ 488 #define CIRCLEQ_FIRST(head) ((head)->cqh_first) 489 #define CIRCLEQ_LAST(head) ((head)->cqh_last) 490 #define CIRCLEQ_END(head) ((void *)(head)) 491 #define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) 492 #define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) 493 #define CIRCLEQ_EMPTY(head) \ 494 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head)) 495 496 #define CIRCLEQ_FOREACH(var, head, field) \ 497 for((var) = CIRCLEQ_FIRST(head); \ 498 (var) != CIRCLEQ_END(head); \ 499 (var) = CIRCLEQ_NEXT(var, field)) 500 501 #define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ 502 for((var) = CIRCLEQ_LAST(head); \ 503 (var) != CIRCLEQ_END(head); \ 504 (var) = CIRCLEQ_PREV(var, field)) 505 506 /* 507 * Circular queue functions. 508 */ 509 #define CIRCLEQ_INIT(head) do { \ 510 (head)->cqh_first = CIRCLEQ_END(head); \ 511 (head)->cqh_last = CIRCLEQ_END(head); \ 512 } while (0) 513 514 #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 515 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 516 (elm)->field.cqe_prev = (listelm); \ 517 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \ 518 (head)->cqh_last = (elm); \ 519 else \ 520 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 521 (listelm)->field.cqe_next = (elm); \ 522 } while (0) 523 524 #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 525 (elm)->field.cqe_next = (listelm); \ 526 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 527 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \ 528 (head)->cqh_first = (elm); \ 529 else \ 530 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 531 (listelm)->field.cqe_prev = (elm); \ 532 } while (0) 533 534 #define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 535 (elm)->field.cqe_next = (head)->cqh_first; \ 536 (elm)->field.cqe_prev = CIRCLEQ_END(head); \ 537 if ((head)->cqh_last == CIRCLEQ_END(head)) \ 538 (head)->cqh_last = (elm); \ 539 else \ 540 (head)->cqh_first->field.cqe_prev = (elm); \ 541 (head)->cqh_first = (elm); \ 542 } while (0) 543 544 #define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 545 (elm)->field.cqe_next = CIRCLEQ_END(head); \ 546 (elm)->field.cqe_prev = (head)->cqh_last; \ 547 if ((head)->cqh_first == CIRCLEQ_END(head)) \ 548 (head)->cqh_first = (elm); \ 549 else \ 550 (head)->cqh_last->field.cqe_next = (elm); \ 551 (head)->cqh_last = (elm); \ 552 } while (0) 553 554 #define CIRCLEQ_REMOVE(head, elm, field) do { \ 555 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \ 556 (head)->cqh_last = (elm)->field.cqe_prev; \ 557 else \ 558 (elm)->field.cqe_next->field.cqe_prev = \ 559 (elm)->field.cqe_prev; \ 560 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \ 561 (head)->cqh_first = (elm)->field.cqe_next; \ 562 else \ 563 (elm)->field.cqe_prev->field.cqe_next = \ 564 (elm)->field.cqe_next; \ 565 } while (0) 566 567 #define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \ 568 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \ 569 CIRCLEQ_END(head)) \ 570 (head).cqh_last = (elm2); \ 571 else \ 572 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \ 573 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \ 574 CIRCLEQ_END(head)) \ 575 (head).cqh_first = (elm2); \ 576 else \ 577 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \ 578 } while (0) 579 580 #endif /* !_FAKE_QUEUE_H_ */ 581