1 /* $OpenBSD: queue.h,v 1.22 2001/06/23 04:39:35 angelos 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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)queue.h 8.5 (Berkeley) 8/20/94 37 */ 38 39 #ifndef _FAKE_QUEUE_H_ 40 #define _FAKE_QUEUE_H_ 41 42 /* 43 * Ignore all <sys/queue.h> since older platforms have broken/incomplete 44 * <sys/queue.h> that are too hard to work around. 45 */ 46 #undef SLIST_HEAD 47 #undef SLIST_HEAD_INITIALIZER 48 #undef SLIST_ENTRY 49 #undef SLIST_FIRST 50 #undef SLIST_END 51 #undef SLIST_EMPTY 52 #undef SLIST_NEXT 53 #undef SLIST_FOREACH 54 #undef SLIST_INIT 55 #undef SLIST_INSERT_AFTER 56 #undef SLIST_INSERT_HEAD 57 #undef SLIST_REMOVE_HEAD 58 #undef SLIST_REMOVE 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) \ 174 struct name { \ 175 struct type *slh_first; /* first element */ \ 176 } 177 178 #define SLIST_HEAD_INITIALIZER(head) \ 179 { NULL } 180 181 #define SLIST_ENTRY(type) \ 182 struct { \ 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 /* 200 * Singly-linked List functions. 201 */ 202 #define SLIST_INIT(head) { \ 203 SLIST_FIRST(head) = SLIST_END(head); \ 204 } 205 206 #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 207 (elm)->field.sle_next = (slistelm)->field.sle_next; \ 208 (slistelm)->field.sle_next = (elm); \ 209 } while (0) 210 211 #define SLIST_INSERT_HEAD(head, elm, field) do { \ 212 (elm)->field.sle_next = (head)->slh_first; \ 213 (head)->slh_first = (elm); \ 214 } while (0) 215 216 #define SLIST_REMOVE_HEAD(head, field) do { \ 217 (head)->slh_first = (head)->slh_first->field.sle_next; \ 218 } while (0) 219 220 #define SLIST_REMOVE(head, elm, type, field) do { \ 221 if ((head)->slh_first == (elm)) { \ 222 SLIST_REMOVE_HEAD((head), field); \ 223 } \ 224 else { \ 225 struct type *curelm = (head)->slh_first; \ 226 while( curelm->field.sle_next != (elm) ) \ 227 curelm = curelm->field.sle_next; \ 228 curelm->field.sle_next = \ 229 curelm->field.sle_next->field.sle_next; \ 230 } \ 231 } while (0) 232 233 /* 234 * List definitions. 235 */ 236 #define LIST_HEAD(name, type) \ 237 struct name { \ 238 struct type *lh_first; /* first element */ \ 239 } 240 241 #define LIST_HEAD_INITIALIZER(head) \ 242 { NULL } 243 244 #define LIST_ENTRY(type) \ 245 struct { \ 246 struct type *le_next; /* next element */ \ 247 struct type **le_prev; /* address of previous next element */ \ 248 } 249 250 /* 251 * List access methods 252 */ 253 #define LIST_FIRST(head) ((head)->lh_first) 254 #define LIST_END(head) NULL 255 #define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) 256 #define LIST_NEXT(elm, field) ((elm)->field.le_next) 257 258 #define LIST_FOREACH(var, head, field) \ 259 for((var) = LIST_FIRST(head); \ 260 (var)!= LIST_END(head); \ 261 (var) = LIST_NEXT(var, field)) 262 263 /* 264 * List functions. 265 */ 266 #define LIST_INIT(head) do { \ 267 LIST_FIRST(head) = LIST_END(head); \ 268 } while (0) 269 270 #define LIST_INSERT_AFTER(listelm, elm, field) do { \ 271 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 272 (listelm)->field.le_next->field.le_prev = \ 273 &(elm)->field.le_next; \ 274 (listelm)->field.le_next = (elm); \ 275 (elm)->field.le_prev = &(listelm)->field.le_next; \ 276 } while (0) 277 278 #define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 279 (elm)->field.le_prev = (listelm)->field.le_prev; \ 280 (elm)->field.le_next = (listelm); \ 281 *(listelm)->field.le_prev = (elm); \ 282 (listelm)->field.le_prev = &(elm)->field.le_next; \ 283 } while (0) 284 285 #define LIST_INSERT_HEAD(head, elm, field) do { \ 286 if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 287 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 288 (head)->lh_first = (elm); \ 289 (elm)->field.le_prev = &(head)->lh_first; \ 290 } while (0) 291 292 #define LIST_REMOVE(elm, field) do { \ 293 if ((elm)->field.le_next != NULL) \ 294 (elm)->field.le_next->field.le_prev = \ 295 (elm)->field.le_prev; \ 296 *(elm)->field.le_prev = (elm)->field.le_next; \ 297 } while (0) 298 299 #define LIST_REPLACE(elm, elm2, field) do { \ 300 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ 301 (elm2)->field.le_next->field.le_prev = \ 302 &(elm2)->field.le_next; \ 303 (elm2)->field.le_prev = (elm)->field.le_prev; \ 304 *(elm2)->field.le_prev = (elm2); \ 305 } while (0) 306 307 /* 308 * Simple queue definitions. 309 */ 310 #define SIMPLEQ_HEAD(name, type) \ 311 struct name { \ 312 struct type *sqh_first; /* first element */ \ 313 struct type **sqh_last; /* addr of last next element */ \ 314 } 315 316 #define SIMPLEQ_HEAD_INITIALIZER(head) \ 317 { NULL, &(head).sqh_first } 318 319 #define SIMPLEQ_ENTRY(type) \ 320 struct { \ 321 struct type *sqe_next; /* next element */ \ 322 } 323 324 /* 325 * Simple queue access methods. 326 */ 327 #define SIMPLEQ_FIRST(head) ((head)->sqh_first) 328 #define SIMPLEQ_END(head) NULL 329 #define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) 330 #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) 331 332 #define SIMPLEQ_FOREACH(var, head, field) \ 333 for((var) = SIMPLEQ_FIRST(head); \ 334 (var) != SIMPLEQ_END(head); \ 335 (var) = SIMPLEQ_NEXT(var, field)) 336 337 /* 338 * Simple queue functions. 339 */ 340 #define SIMPLEQ_INIT(head) do { \ 341 (head)->sqh_first = NULL; \ 342 (head)->sqh_last = &(head)->sqh_first; \ 343 } while (0) 344 345 #define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ 346 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ 347 (head)->sqh_last = &(elm)->field.sqe_next; \ 348 (head)->sqh_first = (elm); \ 349 } while (0) 350 351 #define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ 352 (elm)->field.sqe_next = NULL; \ 353 *(head)->sqh_last = (elm); \ 354 (head)->sqh_last = &(elm)->field.sqe_next; \ 355 } while (0) 356 357 #define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 358 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ 359 (head)->sqh_last = &(elm)->field.sqe_next; \ 360 (listelm)->field.sqe_next = (elm); \ 361 } while (0) 362 363 #define SIMPLEQ_REMOVE_HEAD(head, elm, field) do { \ 364 if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) \ 365 (head)->sqh_last = &(head)->sqh_first; \ 366 } while (0) 367 368 /* 369 * Tail queue definitions. 370 */ 371 #define TAILQ_HEAD(name, type) \ 372 struct name { \ 373 struct type *tqh_first; /* first element */ \ 374 struct type **tqh_last; /* addr of last next element */ \ 375 } 376 377 #define TAILQ_HEAD_INITIALIZER(head) \ 378 { NULL, &(head).tqh_first } 379 380 #define TAILQ_ENTRY(type) \ 381 struct { \ 382 struct type *tqe_next; /* next element */ \ 383 struct type **tqe_prev; /* address of previous next element */ \ 384 } 385 386 /* 387 * tail queue access methods 388 */ 389 #define TAILQ_FIRST(head) ((head)->tqh_first) 390 #define TAILQ_END(head) NULL 391 #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 392 #define TAILQ_LAST(head, headname) \ 393 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 394 /* XXX */ 395 #define TAILQ_PREV(elm, headname, field) \ 396 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 397 #define TAILQ_EMPTY(head) \ 398 (TAILQ_FIRST(head) == TAILQ_END(head)) 399 400 #define TAILQ_FOREACH(var, head, field) \ 401 for((var) = TAILQ_FIRST(head); \ 402 (var) != TAILQ_END(head); \ 403 (var) = TAILQ_NEXT(var, field)) 404 405 #define TAILQ_FOREACH_REVERSE(var, head, field, headname) \ 406 for((var) = TAILQ_LAST(head, headname); \ 407 (var) != TAILQ_END(head); \ 408 (var) = TAILQ_PREV(var, headname, field)) 409 410 /* 411 * Tail queue functions. 412 */ 413 #define TAILQ_INIT(head) do { \ 414 (head)->tqh_first = NULL; \ 415 (head)->tqh_last = &(head)->tqh_first; \ 416 } while (0) 417 418 #define TAILQ_INSERT_HEAD(head, elm, field) do { \ 419 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 420 (head)->tqh_first->field.tqe_prev = \ 421 &(elm)->field.tqe_next; \ 422 else \ 423 (head)->tqh_last = &(elm)->field.tqe_next; \ 424 (head)->tqh_first = (elm); \ 425 (elm)->field.tqe_prev = &(head)->tqh_first; \ 426 } while (0) 427 428 #define TAILQ_INSERT_TAIL(head, elm, field) do { \ 429 (elm)->field.tqe_next = NULL; \ 430 (elm)->field.tqe_prev = (head)->tqh_last; \ 431 *(head)->tqh_last = (elm); \ 432 (head)->tqh_last = &(elm)->field.tqe_next; \ 433 } while (0) 434 435 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 436 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 437 (elm)->field.tqe_next->field.tqe_prev = \ 438 &(elm)->field.tqe_next; \ 439 else \ 440 (head)->tqh_last = &(elm)->field.tqe_next; \ 441 (listelm)->field.tqe_next = (elm); \ 442 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 443 } while (0) 444 445 #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 446 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 447 (elm)->field.tqe_next = (listelm); \ 448 *(listelm)->field.tqe_prev = (elm); \ 449 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ 450 } while (0) 451 452 #define TAILQ_REMOVE(head, elm, field) do { \ 453 if (((elm)->field.tqe_next) != NULL) \ 454 (elm)->field.tqe_next->field.tqe_prev = \ 455 (elm)->field.tqe_prev; \ 456 else \ 457 (head)->tqh_last = (elm)->field.tqe_prev; \ 458 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 459 } while (0) 460 461 #define TAILQ_REPLACE(head, elm, elm2, field) do { \ 462 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ 463 (elm2)->field.tqe_next->field.tqe_prev = \ 464 &(elm2)->field.tqe_next; \ 465 else \ 466 (head)->tqh_last = &(elm2)->field.tqe_next; \ 467 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 468 *(elm2)->field.tqe_prev = (elm2); \ 469 } while (0) 470 471 /* 472 * Circular queue definitions. 473 */ 474 #define CIRCLEQ_HEAD(name, type) \ 475 struct name { \ 476 struct type *cqh_first; /* first element */ \ 477 struct type *cqh_last; /* last element */ \ 478 } 479 480 #define CIRCLEQ_HEAD_INITIALIZER(head) \ 481 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } 482 483 #define CIRCLEQ_ENTRY(type) \ 484 struct { \ 485 struct type *cqe_next; /* next element */ \ 486 struct type *cqe_prev; /* previous element */ \ 487 } 488 489 /* 490 * Circular queue access methods 491 */ 492 #define CIRCLEQ_FIRST(head) ((head)->cqh_first) 493 #define CIRCLEQ_LAST(head) ((head)->cqh_last) 494 #define CIRCLEQ_END(head) ((void *)(head)) 495 #define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) 496 #define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) 497 #define CIRCLEQ_EMPTY(head) \ 498 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head)) 499 500 #define CIRCLEQ_FOREACH(var, head, field) \ 501 for((var) = CIRCLEQ_FIRST(head); \ 502 (var) != CIRCLEQ_END(head); \ 503 (var) = CIRCLEQ_NEXT(var, field)) 504 505 #define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ 506 for((var) = CIRCLEQ_LAST(head); \ 507 (var) != CIRCLEQ_END(head); \ 508 (var) = CIRCLEQ_PREV(var, field)) 509 510 /* 511 * Circular queue functions. 512 */ 513 #define CIRCLEQ_INIT(head) do { \ 514 (head)->cqh_first = CIRCLEQ_END(head); \ 515 (head)->cqh_last = CIRCLEQ_END(head); \ 516 } while (0) 517 518 #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 519 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 520 (elm)->field.cqe_prev = (listelm); \ 521 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \ 522 (head)->cqh_last = (elm); \ 523 else \ 524 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 525 (listelm)->field.cqe_next = (elm); \ 526 } while (0) 527 528 #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 529 (elm)->field.cqe_next = (listelm); \ 530 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 531 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \ 532 (head)->cqh_first = (elm); \ 533 else \ 534 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 535 (listelm)->field.cqe_prev = (elm); \ 536 } while (0) 537 538 #define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 539 (elm)->field.cqe_next = (head)->cqh_first; \ 540 (elm)->field.cqe_prev = CIRCLEQ_END(head); \ 541 if ((head)->cqh_last == CIRCLEQ_END(head)) \ 542 (head)->cqh_last = (elm); \ 543 else \ 544 (head)->cqh_first->field.cqe_prev = (elm); \ 545 (head)->cqh_first = (elm); \ 546 } while (0) 547 548 #define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 549 (elm)->field.cqe_next = CIRCLEQ_END(head); \ 550 (elm)->field.cqe_prev = (head)->cqh_last; \ 551 if ((head)->cqh_first == CIRCLEQ_END(head)) \ 552 (head)->cqh_first = (elm); \ 553 else \ 554 (head)->cqh_last->field.cqe_next = (elm); \ 555 (head)->cqh_last = (elm); \ 556 } while (0) 557 558 #define CIRCLEQ_REMOVE(head, elm, field) do { \ 559 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \ 560 (head)->cqh_last = (elm)->field.cqe_prev; \ 561 else \ 562 (elm)->field.cqe_next->field.cqe_prev = \ 563 (elm)->field.cqe_prev; \ 564 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \ 565 (head)->cqh_first = (elm)->field.cqe_next; \ 566 else \ 567 (elm)->field.cqe_prev->field.cqe_next = \ 568 (elm)->field.cqe_next; \ 569 } while (0) 570 571 #define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \ 572 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \ 573 CIRCLEQ_END(head)) \ 574 (head).cqh_last = (elm2); \ 575 else \ 576 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \ 577 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \ 578 CIRCLEQ_END(head)) \ 579 (head).cqh_first = (elm2); \ 580 else \ 581 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \ 582 } while (0) 583 584 #endif /* !_FAKE_QUEUE_H_ */ 585