1 /* $OpenBSD: queue.h,v 1.36 2012/04/11 13:29:14 naddy 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_FOREACH_SAFE 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_AFTER 59 #undef SLIST_REMOVE 60 #undef SLIST_REMOVE_NEXT 61 #undef LIST_HEAD 62 #undef LIST_HEAD_INITIALIZER 63 #undef LIST_ENTRY 64 #undef LIST_FIRST 65 #undef LIST_END 66 #undef LIST_EMPTY 67 #undef LIST_NEXT 68 #undef LIST_FOREACH 69 #undef LIST_FOREACH_SAFE 70 #undef LIST_INIT 71 #undef LIST_INSERT_AFTER 72 #undef LIST_INSERT_BEFORE 73 #undef LIST_INSERT_HEAD 74 #undef LIST_REMOVE 75 #undef LIST_REPLACE 76 #undef SIMPLEQ_HEAD 77 #undef SIMPLEQ_HEAD_INITIALIZER 78 #undef SIMPLEQ_ENTRY 79 #undef SIMPLEQ_FIRST 80 #undef SIMPLEQ_END 81 #undef SIMPLEQ_EMPTY 82 #undef SIMPLEQ_NEXT 83 #undef SIMPLEQ_FOREACH 84 #undef SIMPLEQ_INIT 85 #undef SIMPLEQ_INSERT_HEAD 86 #undef SIMPLEQ_INSERT_TAIL 87 #undef SIMPLEQ_INSERT_AFTER 88 #undef SIMPLEQ_REMOVE_HEAD 89 #undef TAILQ_HEAD 90 #undef TAILQ_HEAD_INITIALIZER 91 #undef TAILQ_ENTRY 92 #undef TAILQ_FIRST 93 #undef TAILQ_END 94 #undef TAILQ_NEXT 95 #undef TAILQ_LAST 96 #undef TAILQ_PREV 97 #undef TAILQ_EMPTY 98 #undef TAILQ_FOREACH 99 #undef TAILQ_FOREACH_REVERSE 100 #undef TAILQ_FOREACH_SAFE 101 #undef TAILQ_FOREACH_REVERSE_SAFE 102 #undef TAILQ_INIT 103 #undef TAILQ_INSERT_HEAD 104 #undef TAILQ_INSERT_TAIL 105 #undef TAILQ_INSERT_AFTER 106 #undef TAILQ_INSERT_BEFORE 107 #undef TAILQ_REMOVE 108 #undef TAILQ_REPLACE 109 #undef CIRCLEQ_HEAD 110 #undef CIRCLEQ_HEAD_INITIALIZER 111 #undef CIRCLEQ_ENTRY 112 #undef CIRCLEQ_FIRST 113 #undef CIRCLEQ_LAST 114 #undef CIRCLEQ_END 115 #undef CIRCLEQ_NEXT 116 #undef CIRCLEQ_PREV 117 #undef CIRCLEQ_EMPTY 118 #undef CIRCLEQ_FOREACH 119 #undef CIRCLEQ_FOREACH_REVERSE 120 #undef CIRCLEQ_INIT 121 #undef CIRCLEQ_INSERT_AFTER 122 #undef CIRCLEQ_INSERT_BEFORE 123 #undef CIRCLEQ_INSERT_HEAD 124 #undef CIRCLEQ_INSERT_TAIL 125 #undef CIRCLEQ_REMOVE 126 #undef CIRCLEQ_REPLACE 127 128 /* 129 * This file defines five types of data structures: singly-linked lists, 130 * lists, simple queues, tail queues, and circular queues. 131 * 132 * 133 * A singly-linked list is headed by a single forward pointer. The elements 134 * are singly linked for minimum space and pointer manipulation overhead at 135 * the expense of O(n) removal for arbitrary elements. New elements can be 136 * added to the list after an existing element or at the head of the list. 137 * Elements being removed from the head of the list should use the explicit 138 * macro for this purpose for optimum efficiency. A singly-linked list may 139 * only be traversed in the forward direction. Singly-linked lists are ideal 140 * for applications with large datasets and few or no removals or for 141 * implementing a LIFO queue. 142 * 143 * A list is headed by a single forward pointer (or an array of forward 144 * pointers for a hash table header). The elements are doubly linked 145 * so that an arbitrary element can be removed without a need to 146 * traverse the list. New elements can be added to the list before 147 * or after an existing element or at the head of the list. A list 148 * may only be traversed in the forward direction. 149 * 150 * A simple queue is headed by a pair of pointers, one the head of the 151 * list and the other to the tail of the list. The elements are singly 152 * linked to save space, so elements can only be removed from the 153 * head of the list. New elements can be added to the list before or after 154 * an existing element, at the head of the list, or at the end of the 155 * list. A simple queue may only be traversed in the forward direction. 156 * 157 * A tail queue is headed by a pair of pointers, one to the head of the 158 * list and the other to the tail of the list. The elements are doubly 159 * linked so that an arbitrary element can be removed without a need to 160 * traverse the list. New elements can be added to the list before or 161 * after an existing element, at the head of the list, or at the end of 162 * the list. A tail queue may be traversed in either direction. 163 * 164 * A circle queue is headed by a pair of pointers, one to the head of the 165 * list and the other to the tail of the list. The elements are doubly 166 * linked so that an arbitrary element can be removed without a need to 167 * traverse the list. New elements can be added to the list before or after 168 * an existing element, at the head of the list, or at the end of the list. 169 * A circle queue may be traversed in either direction, but has a more 170 * complex end of list detection. 171 * 172 * For details on the use of these macros, see the queue(3) manual page. 173 */ 174 175 #if defined(QUEUE_MACRO_DEBUG) || (defined(_KERNEL) && defined(DIAGNOSTIC)) 176 #define _Q_INVALIDATE(a) (a) = ((void *)-1) 177 #else 178 #define _Q_INVALIDATE(a) 179 #endif 180 181 /* 182 * Singly-linked List definitions. 183 */ 184 #define SLIST_HEAD(name, type) \ 185 struct name { \ 186 struct type *slh_first; /* first element */ \ 187 } 188 189 #define SLIST_HEAD_INITIALIZER(head) \ 190 { NULL } 191 192 #define SLIST_ENTRY(type) \ 193 struct { \ 194 struct type *sle_next; /* next element */ \ 195 } 196 197 /* 198 * Singly-linked List access methods. 199 */ 200 #define SLIST_FIRST(head) ((head)->slh_first) 201 #define SLIST_END(head) NULL 202 #define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) 203 #define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 204 205 #define SLIST_FOREACH(var, head, field) \ 206 for((var) = SLIST_FIRST(head); \ 207 (var) != SLIST_END(head); \ 208 (var) = SLIST_NEXT(var, field)) 209 210 #define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 211 for ((var) = SLIST_FIRST(head); \ 212 (var) && ((tvar) = SLIST_NEXT(var, field), 1); \ 213 (var) = (tvar)) 214 215 /* 216 * Singly-linked List functions. 217 */ 218 #define SLIST_INIT(head) { \ 219 SLIST_FIRST(head) = SLIST_END(head); \ 220 } 221 222 #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 223 (elm)->field.sle_next = (slistelm)->field.sle_next; \ 224 (slistelm)->field.sle_next = (elm); \ 225 } while (0) 226 227 #define SLIST_INSERT_HEAD(head, elm, field) do { \ 228 (elm)->field.sle_next = (head)->slh_first; \ 229 (head)->slh_first = (elm); \ 230 } while (0) 231 232 #define SLIST_REMOVE_AFTER(elm, field) do { \ 233 (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \ 234 } while (0) 235 236 #define SLIST_REMOVE_HEAD(head, field) do { \ 237 (head)->slh_first = (head)->slh_first->field.sle_next; \ 238 } while (0) 239 240 #define SLIST_REMOVE(head, elm, type, field) do { \ 241 if ((head)->slh_first == (elm)) { \ 242 SLIST_REMOVE_HEAD((head), field); \ 243 } else { \ 244 struct type *curelm = (head)->slh_first; \ 245 \ 246 while (curelm->field.sle_next != (elm)) \ 247 curelm = curelm->field.sle_next; \ 248 curelm->field.sle_next = \ 249 curelm->field.sle_next->field.sle_next; \ 250 _Q_INVALIDATE((elm)->field.sle_next); \ 251 } \ 252 } while (0) 253 254 /* 255 * List definitions. 256 */ 257 #define LIST_HEAD(name, type) \ 258 struct name { \ 259 struct type *lh_first; /* first element */ \ 260 } 261 262 #define LIST_HEAD_INITIALIZER(head) \ 263 { NULL } 264 265 #define LIST_ENTRY(type) \ 266 struct { \ 267 struct type *le_next; /* next element */ \ 268 struct type **le_prev; /* address of previous next element */ \ 269 } 270 271 /* 272 * List access methods 273 */ 274 #define LIST_FIRST(head) ((head)->lh_first) 275 #define LIST_END(head) NULL 276 #define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) 277 #define LIST_NEXT(elm, field) ((elm)->field.le_next) 278 279 #define LIST_FOREACH(var, head, field) \ 280 for((var) = LIST_FIRST(head); \ 281 (var)!= LIST_END(head); \ 282 (var) = LIST_NEXT(var, field)) 283 284 #define LIST_FOREACH_SAFE(var, head, field, tvar) \ 285 for ((var) = LIST_FIRST(head); \ 286 (var) && ((tvar) = LIST_NEXT(var, field), 1); \ 287 (var) = (tvar)) 288 289 /* 290 * List functions. 291 */ 292 #define LIST_INIT(head) do { \ 293 LIST_FIRST(head) = LIST_END(head); \ 294 } while (0) 295 296 #define LIST_INSERT_AFTER(listelm, elm, field) do { \ 297 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 298 (listelm)->field.le_next->field.le_prev = \ 299 &(elm)->field.le_next; \ 300 (listelm)->field.le_next = (elm); \ 301 (elm)->field.le_prev = &(listelm)->field.le_next; \ 302 } while (0) 303 304 #define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 305 (elm)->field.le_prev = (listelm)->field.le_prev; \ 306 (elm)->field.le_next = (listelm); \ 307 *(listelm)->field.le_prev = (elm); \ 308 (listelm)->field.le_prev = &(elm)->field.le_next; \ 309 } while (0) 310 311 #define LIST_INSERT_HEAD(head, elm, field) do { \ 312 if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 313 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 314 (head)->lh_first = (elm); \ 315 (elm)->field.le_prev = &(head)->lh_first; \ 316 } while (0) 317 318 #define LIST_REMOVE(elm, field) do { \ 319 if ((elm)->field.le_next != NULL) \ 320 (elm)->field.le_next->field.le_prev = \ 321 (elm)->field.le_prev; \ 322 *(elm)->field.le_prev = (elm)->field.le_next; \ 323 _Q_INVALIDATE((elm)->field.le_prev); \ 324 _Q_INVALIDATE((elm)->field.le_next); \ 325 } while (0) 326 327 #define LIST_REPLACE(elm, elm2, field) do { \ 328 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ 329 (elm2)->field.le_next->field.le_prev = \ 330 &(elm2)->field.le_next; \ 331 (elm2)->field.le_prev = (elm)->field.le_prev; \ 332 *(elm2)->field.le_prev = (elm2); \ 333 _Q_INVALIDATE((elm)->field.le_prev); \ 334 _Q_INVALIDATE((elm)->field.le_next); \ 335 } while (0) 336 337 /* 338 * Simple queue definitions. 339 */ 340 #define SIMPLEQ_HEAD(name, type) \ 341 struct name { \ 342 struct type *sqh_first; /* first element */ \ 343 struct type **sqh_last; /* addr of last next element */ \ 344 } 345 346 #define SIMPLEQ_HEAD_INITIALIZER(head) \ 347 { NULL, &(head).sqh_first } 348 349 #define SIMPLEQ_ENTRY(type) \ 350 struct { \ 351 struct type *sqe_next; /* next element */ \ 352 } 353 354 /* 355 * Simple queue access methods. 356 */ 357 #define SIMPLEQ_FIRST(head) ((head)->sqh_first) 358 #define SIMPLEQ_END(head) NULL 359 #define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) 360 #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) 361 362 #define SIMPLEQ_FOREACH(var, head, field) \ 363 for((var) = SIMPLEQ_FIRST(head); \ 364 (var) != SIMPLEQ_END(head); \ 365 (var) = SIMPLEQ_NEXT(var, field)) 366 367 #define SIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \ 368 for ((var) = SIMPLEQ_FIRST(head); \ 369 (var) && ((tvar) = SIMPLEQ_NEXT(var, field), 1); \ 370 (var) = (tvar)) 371 372 /* 373 * Simple queue functions. 374 */ 375 #define SIMPLEQ_INIT(head) do { \ 376 (head)->sqh_first = NULL; \ 377 (head)->sqh_last = &(head)->sqh_first; \ 378 } while (0) 379 380 #define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ 381 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ 382 (head)->sqh_last = &(elm)->field.sqe_next; \ 383 (head)->sqh_first = (elm); \ 384 } while (0) 385 386 #define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ 387 (elm)->field.sqe_next = NULL; \ 388 *(head)->sqh_last = (elm); \ 389 (head)->sqh_last = &(elm)->field.sqe_next; \ 390 } while (0) 391 392 #define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 393 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ 394 (head)->sqh_last = &(elm)->field.sqe_next; \ 395 (listelm)->field.sqe_next = (elm); \ 396 } while (0) 397 398 #define SIMPLEQ_REMOVE_HEAD(head, field) do { \ 399 if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \ 400 (head)->sqh_last = &(head)->sqh_first; \ 401 } while (0) 402 403 #define SIMPLEQ_REMOVE_AFTER(head, elm, field) do { \ 404 if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \ 405 == NULL) \ 406 (head)->sqh_last = &(elm)->field.sqe_next; \ 407 } while (0) 408 409 /* 410 * Tail queue definitions. 411 */ 412 #define TAILQ_HEAD(name, type) \ 413 struct name { \ 414 struct type *tqh_first; /* first element */ \ 415 struct type **tqh_last; /* addr of last next element */ \ 416 } 417 418 #define TAILQ_HEAD_INITIALIZER(head) \ 419 { NULL, &(head).tqh_first } 420 421 #define TAILQ_ENTRY(type) \ 422 struct { \ 423 struct type *tqe_next; /* next element */ \ 424 struct type **tqe_prev; /* address of previous next element */ \ 425 } 426 427 /* 428 * tail queue access methods 429 */ 430 #define TAILQ_FIRST(head) ((head)->tqh_first) 431 #define TAILQ_END(head) NULL 432 #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 433 #define TAILQ_LAST(head, headname) \ 434 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 435 /* XXX */ 436 #define TAILQ_PREV(elm, headname, field) \ 437 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 438 #define TAILQ_EMPTY(head) \ 439 (TAILQ_FIRST(head) == TAILQ_END(head)) 440 441 #define TAILQ_FOREACH(var, head, field) \ 442 for((var) = TAILQ_FIRST(head); \ 443 (var) != TAILQ_END(head); \ 444 (var) = TAILQ_NEXT(var, field)) 445 446 #define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 447 for ((var) = TAILQ_FIRST(head); \ 448 (var) != TAILQ_END(head) && \ 449 ((tvar) = TAILQ_NEXT(var, field), 1); \ 450 (var) = (tvar)) 451 452 453 #define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 454 for((var) = TAILQ_LAST(head, headname); \ 455 (var) != TAILQ_END(head); \ 456 (var) = TAILQ_PREV(var, headname, field)) 457 458 #define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 459 for ((var) = TAILQ_LAST(head, headname); \ 460 (var) != TAILQ_END(head) && \ 461 ((tvar) = TAILQ_PREV(var, headname, field), 1); \ 462 (var) = (tvar)) 463 464 /* 465 * Tail queue functions. 466 */ 467 #define TAILQ_INIT(head) do { \ 468 (head)->tqh_first = NULL; \ 469 (head)->tqh_last = &(head)->tqh_first; \ 470 } while (0) 471 472 #define TAILQ_INSERT_HEAD(head, elm, field) do { \ 473 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 474 (head)->tqh_first->field.tqe_prev = \ 475 &(elm)->field.tqe_next; \ 476 else \ 477 (head)->tqh_last = &(elm)->field.tqe_next; \ 478 (head)->tqh_first = (elm); \ 479 (elm)->field.tqe_prev = &(head)->tqh_first; \ 480 } while (0) 481 482 #define TAILQ_INSERT_TAIL(head, elm, field) do { \ 483 (elm)->field.tqe_next = NULL; \ 484 (elm)->field.tqe_prev = (head)->tqh_last; \ 485 *(head)->tqh_last = (elm); \ 486 (head)->tqh_last = &(elm)->field.tqe_next; \ 487 } while (0) 488 489 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 490 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 491 (elm)->field.tqe_next->field.tqe_prev = \ 492 &(elm)->field.tqe_next; \ 493 else \ 494 (head)->tqh_last = &(elm)->field.tqe_next; \ 495 (listelm)->field.tqe_next = (elm); \ 496 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 497 } while (0) 498 499 #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 500 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 501 (elm)->field.tqe_next = (listelm); \ 502 *(listelm)->field.tqe_prev = (elm); \ 503 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ 504 } while (0) 505 506 #define TAILQ_REMOVE(head, elm, field) do { \ 507 if (((elm)->field.tqe_next) != NULL) \ 508 (elm)->field.tqe_next->field.tqe_prev = \ 509 (elm)->field.tqe_prev; \ 510 else \ 511 (head)->tqh_last = (elm)->field.tqe_prev; \ 512 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 513 _Q_INVALIDATE((elm)->field.tqe_prev); \ 514 _Q_INVALIDATE((elm)->field.tqe_next); \ 515 } while (0) 516 517 #define TAILQ_REPLACE(head, elm, elm2, field) do { \ 518 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ 519 (elm2)->field.tqe_next->field.tqe_prev = \ 520 &(elm2)->field.tqe_next; \ 521 else \ 522 (head)->tqh_last = &(elm2)->field.tqe_next; \ 523 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 524 *(elm2)->field.tqe_prev = (elm2); \ 525 _Q_INVALIDATE((elm)->field.tqe_prev); \ 526 _Q_INVALIDATE((elm)->field.tqe_next); \ 527 } while (0) 528 529 /* 530 * Circular queue definitions. 531 */ 532 #define CIRCLEQ_HEAD(name, type) \ 533 struct name { \ 534 struct type *cqh_first; /* first element */ \ 535 struct type *cqh_last; /* last element */ \ 536 } 537 538 #define CIRCLEQ_HEAD_INITIALIZER(head) \ 539 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } 540 541 #define CIRCLEQ_ENTRY(type) \ 542 struct { \ 543 struct type *cqe_next; /* next element */ \ 544 struct type *cqe_prev; /* previous element */ \ 545 } 546 547 /* 548 * Circular queue access methods 549 */ 550 #define CIRCLEQ_FIRST(head) ((head)->cqh_first) 551 #define CIRCLEQ_LAST(head) ((head)->cqh_last) 552 #define CIRCLEQ_END(head) ((void *)(head)) 553 #define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) 554 #define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) 555 #define CIRCLEQ_EMPTY(head) \ 556 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head)) 557 558 #define CIRCLEQ_FOREACH(var, head, field) \ 559 for((var) = CIRCLEQ_FIRST(head); \ 560 (var) != CIRCLEQ_END(head); \ 561 (var) = CIRCLEQ_NEXT(var, field)) 562 563 #define CIRCLEQ_FOREACH_SAFE(var, head, field, tvar) \ 564 for ((var) = CIRCLEQ_FIRST(head); \ 565 (var) != CIRCLEQ_END(head) && \ 566 ((tvar) = CIRCLEQ_NEXT(var, field), 1); \ 567 (var) = (tvar)) 568 569 #define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ 570 for((var) = CIRCLEQ_LAST(head); \ 571 (var) != CIRCLEQ_END(head); \ 572 (var) = CIRCLEQ_PREV(var, field)) 573 574 #define CIRCLEQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 575 for ((var) = CIRCLEQ_LAST(head, headname); \ 576 (var) != CIRCLEQ_END(head) && \ 577 ((tvar) = CIRCLEQ_PREV(var, headname, field), 1); \ 578 (var) = (tvar)) 579 580 /* 581 * Circular queue functions. 582 */ 583 #define CIRCLEQ_INIT(head) do { \ 584 (head)->cqh_first = CIRCLEQ_END(head); \ 585 (head)->cqh_last = CIRCLEQ_END(head); \ 586 } while (0) 587 588 #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 589 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 590 (elm)->field.cqe_prev = (listelm); \ 591 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \ 592 (head)->cqh_last = (elm); \ 593 else \ 594 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 595 (listelm)->field.cqe_next = (elm); \ 596 } while (0) 597 598 #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 599 (elm)->field.cqe_next = (listelm); \ 600 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 601 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \ 602 (head)->cqh_first = (elm); \ 603 else \ 604 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 605 (listelm)->field.cqe_prev = (elm); \ 606 } while (0) 607 608 #define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 609 (elm)->field.cqe_next = (head)->cqh_first; \ 610 (elm)->field.cqe_prev = CIRCLEQ_END(head); \ 611 if ((head)->cqh_last == CIRCLEQ_END(head)) \ 612 (head)->cqh_last = (elm); \ 613 else \ 614 (head)->cqh_first->field.cqe_prev = (elm); \ 615 (head)->cqh_first = (elm); \ 616 } while (0) 617 618 #define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 619 (elm)->field.cqe_next = CIRCLEQ_END(head); \ 620 (elm)->field.cqe_prev = (head)->cqh_last; \ 621 if ((head)->cqh_first == CIRCLEQ_END(head)) \ 622 (head)->cqh_first = (elm); \ 623 else \ 624 (head)->cqh_last->field.cqe_next = (elm); \ 625 (head)->cqh_last = (elm); \ 626 } while (0) 627 628 #define CIRCLEQ_REMOVE(head, elm, field) do { \ 629 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \ 630 (head)->cqh_last = (elm)->field.cqe_prev; \ 631 else \ 632 (elm)->field.cqe_next->field.cqe_prev = \ 633 (elm)->field.cqe_prev; \ 634 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \ 635 (head)->cqh_first = (elm)->field.cqe_next; \ 636 else \ 637 (elm)->field.cqe_prev->field.cqe_next = \ 638 (elm)->field.cqe_next; \ 639 _Q_INVALIDATE((elm)->field.cqe_prev); \ 640 _Q_INVALIDATE((elm)->field.cqe_next); \ 641 } while (0) 642 643 #define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \ 644 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \ 645 CIRCLEQ_END(head)) \ 646 (head).cqh_last = (elm2); \ 647 else \ 648 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \ 649 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \ 650 CIRCLEQ_END(head)) \ 651 (head).cqh_first = (elm2); \ 652 else \ 653 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \ 654 _Q_INVALIDATE((elm)->field.cqe_prev); \ 655 _Q_INVALIDATE((elm)->field.cqe_next); \ 656 } while (0) 657 658 #endif /* !_FAKE_QUEUE_H_ */ 659