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_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 #if defined(QUEUE_MACRO_DEBUG) || (defined(_KERNEL) && defined(DIAGNOSTIC)) 171 #define _Q_INVALIDATE(a) (a) = ((void *)-1) 172 #else 173 #define _Q_INVALIDATE(a) 174 #endif 175 176 /* 177 * Singly-linked List definitions. 178 */ 179 #define SLIST_HEAD(name, type) \ 180 struct name { \ 181 struct type *slh_first; /* first element */ \ 182 } 183 184 #define SLIST_HEAD_INITIALIZER(head) \ 185 { NULL } 186 187 #define SLIST_ENTRY(type) \ 188 struct { \ 189 struct type *sle_next; /* next element */ \ 190 } 191 192 /* 193 * Singly-linked List access methods. 194 */ 195 #define SLIST_FIRST(head) ((head)->slh_first) 196 #define SLIST_END(head) NULL 197 #define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) 198 #define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 199 200 #define SLIST_FOREACH(var, head, field) \ 201 for((var) = SLIST_FIRST(head); \ 202 (var) != SLIST_END(head); \ 203 (var) = SLIST_NEXT(var, field)) 204 205 #define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 206 for ((var) = SLIST_FIRST(head); \ 207 (var) && ((tvar) = SLIST_NEXT(var, field), 1); \ 208 (var) = (tvar)) 209 210 /* 211 * Singly-linked List functions. 212 */ 213 #define SLIST_INIT(head) { \ 214 SLIST_FIRST(head) = SLIST_END(head); \ 215 } 216 217 #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 218 (elm)->field.sle_next = (slistelm)->field.sle_next; \ 219 (slistelm)->field.sle_next = (elm); \ 220 } while (0) 221 222 #define SLIST_INSERT_HEAD(head, elm, field) do { \ 223 (elm)->field.sle_next = (head)->slh_first; \ 224 (head)->slh_first = (elm); \ 225 } while (0) 226 227 #define SLIST_REMOVE_AFTER(elm, field) do { \ 228 (elm)->field.sle_next = (elm)->field.sle_next->field.sle_next; \ 229 } while (0) 230 231 #define SLIST_REMOVE_HEAD(head, field) do { \ 232 (head)->slh_first = (head)->slh_first->field.sle_next; \ 233 } while (0) 234 235 #define SLIST_REMOVE(head, elm, type, field) do { \ 236 if ((head)->slh_first == (elm)) { \ 237 SLIST_REMOVE_HEAD((head), field); \ 238 } else { \ 239 struct type *curelm = (head)->slh_first; \ 240 \ 241 while (curelm->field.sle_next != (elm)) \ 242 curelm = curelm->field.sle_next; \ 243 curelm->field.sle_next = \ 244 curelm->field.sle_next->field.sle_next; \ 245 _Q_INVALIDATE((elm)->field.sle_next); \ 246 } \ 247 } while (0) 248 249 /* 250 * List definitions. 251 */ 252 #define LIST_HEAD(name, type) \ 253 struct name { \ 254 struct type *lh_first; /* first element */ \ 255 } 256 257 #define LIST_HEAD_INITIALIZER(head) \ 258 { NULL } 259 260 #define LIST_ENTRY(type) \ 261 struct { \ 262 struct type *le_next; /* next element */ \ 263 struct type **le_prev; /* address of previous next element */ \ 264 } 265 266 /* 267 * List access methods 268 */ 269 #define LIST_FIRST(head) ((head)->lh_first) 270 #define LIST_END(head) NULL 271 #define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) 272 #define LIST_NEXT(elm, field) ((elm)->field.le_next) 273 274 #define LIST_FOREACH(var, head, field) \ 275 for((var) = LIST_FIRST(head); \ 276 (var)!= LIST_END(head); \ 277 (var) = LIST_NEXT(var, field)) 278 279 #define LIST_FOREACH_SAFE(var, head, field, tvar) \ 280 for ((var) = LIST_FIRST(head); \ 281 (var) && ((tvar) = LIST_NEXT(var, field), 1); \ 282 (var) = (tvar)) 283 284 /* 285 * List functions. 286 */ 287 #define LIST_INIT(head) do { \ 288 LIST_FIRST(head) = LIST_END(head); \ 289 } while (0) 290 291 #define LIST_INSERT_AFTER(listelm, elm, field) do { \ 292 if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 293 (listelm)->field.le_next->field.le_prev = \ 294 &(elm)->field.le_next; \ 295 (listelm)->field.le_next = (elm); \ 296 (elm)->field.le_prev = &(listelm)->field.le_next; \ 297 } while (0) 298 299 #define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 300 (elm)->field.le_prev = (listelm)->field.le_prev; \ 301 (elm)->field.le_next = (listelm); \ 302 *(listelm)->field.le_prev = (elm); \ 303 (listelm)->field.le_prev = &(elm)->field.le_next; \ 304 } while (0) 305 306 #define LIST_INSERT_HEAD(head, elm, field) do { \ 307 if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 308 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 309 (head)->lh_first = (elm); \ 310 (elm)->field.le_prev = &(head)->lh_first; \ 311 } while (0) 312 313 #define LIST_REMOVE(elm, field) do { \ 314 if ((elm)->field.le_next != NULL) \ 315 (elm)->field.le_next->field.le_prev = \ 316 (elm)->field.le_prev; \ 317 *(elm)->field.le_prev = (elm)->field.le_next; \ 318 _Q_INVALIDATE((elm)->field.le_prev); \ 319 _Q_INVALIDATE((elm)->field.le_next); \ 320 } while (0) 321 322 #define LIST_REPLACE(elm, elm2, field) do { \ 323 if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ 324 (elm2)->field.le_next->field.le_prev = \ 325 &(elm2)->field.le_next; \ 326 (elm2)->field.le_prev = (elm)->field.le_prev; \ 327 *(elm2)->field.le_prev = (elm2); \ 328 _Q_INVALIDATE((elm)->field.le_prev); \ 329 _Q_INVALIDATE((elm)->field.le_next); \ 330 } while (0) 331 332 /* 333 * Simple queue definitions. 334 */ 335 #define SIMPLEQ_HEAD(name, type) \ 336 struct name { \ 337 struct type *sqh_first; /* first element */ \ 338 struct type **sqh_last; /* addr of last next element */ \ 339 } 340 341 #define SIMPLEQ_HEAD_INITIALIZER(head) \ 342 { NULL, &(head).sqh_first } 343 344 #define SIMPLEQ_ENTRY(type) \ 345 struct { \ 346 struct type *sqe_next; /* next element */ \ 347 } 348 349 /* 350 * Simple queue access methods. 351 */ 352 #define SIMPLEQ_FIRST(head) ((head)->sqh_first) 353 #define SIMPLEQ_END(head) NULL 354 #define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) 355 #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) 356 357 #define SIMPLEQ_FOREACH(var, head, field) \ 358 for((var) = SIMPLEQ_FIRST(head); \ 359 (var) != SIMPLEQ_END(head); \ 360 (var) = SIMPLEQ_NEXT(var, field)) 361 362 #define SIMPLEQ_FOREACH_SAFE(var, head, field, tvar) \ 363 for ((var) = SIMPLEQ_FIRST(head); \ 364 (var) && ((tvar) = SIMPLEQ_NEXT(var, field), 1); \ 365 (var) = (tvar)) 366 367 /* 368 * Simple queue functions. 369 */ 370 #define SIMPLEQ_INIT(head) do { \ 371 (head)->sqh_first = NULL; \ 372 (head)->sqh_last = &(head)->sqh_first; \ 373 } while (0) 374 375 #define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ 376 if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ 377 (head)->sqh_last = &(elm)->field.sqe_next; \ 378 (head)->sqh_first = (elm); \ 379 } while (0) 380 381 #define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ 382 (elm)->field.sqe_next = NULL; \ 383 *(head)->sqh_last = (elm); \ 384 (head)->sqh_last = &(elm)->field.sqe_next; \ 385 } while (0) 386 387 #define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 388 if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ 389 (head)->sqh_last = &(elm)->field.sqe_next; \ 390 (listelm)->field.sqe_next = (elm); \ 391 } while (0) 392 393 #define SIMPLEQ_REMOVE_HEAD(head, field) do { \ 394 if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \ 395 (head)->sqh_last = &(head)->sqh_first; \ 396 } while (0) 397 398 #define SIMPLEQ_REMOVE_AFTER(head, elm, field) do { \ 399 if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \ 400 == NULL) \ 401 (head)->sqh_last = &(elm)->field.sqe_next; \ 402 } while (0) 403 404 /* 405 * Tail queue definitions. 406 */ 407 #define TAILQ_HEAD(name, type) \ 408 struct name { \ 409 struct type *tqh_first; /* first element */ \ 410 struct type **tqh_last; /* addr of last next element */ \ 411 } 412 413 #define TAILQ_HEAD_INITIALIZER(head) \ 414 { NULL, &(head).tqh_first } 415 416 #define TAILQ_ENTRY(type) \ 417 struct { \ 418 struct type *tqe_next; /* next element */ \ 419 struct type **tqe_prev; /* address of previous next element */ \ 420 } 421 422 /* 423 * tail queue access methods 424 */ 425 #define TAILQ_FIRST(head) ((head)->tqh_first) 426 #define TAILQ_END(head) NULL 427 #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 428 #define TAILQ_LAST(head, headname) \ 429 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 430 /* XXX */ 431 #define TAILQ_PREV(elm, headname, field) \ 432 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 433 #define TAILQ_EMPTY(head) \ 434 (TAILQ_FIRST(head) == TAILQ_END(head)) 435 436 #define TAILQ_FOREACH(var, head, field) \ 437 for((var) = TAILQ_FIRST(head); \ 438 (var) != TAILQ_END(head); \ 439 (var) = TAILQ_NEXT(var, field)) 440 441 #define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 442 for ((var) = TAILQ_FIRST(head); \ 443 (var) != TAILQ_END(head) && \ 444 ((tvar) = TAILQ_NEXT(var, field), 1); \ 445 (var) = (tvar)) 446 447 448 #define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 449 for((var) = TAILQ_LAST(head, headname); \ 450 (var) != TAILQ_END(head); \ 451 (var) = TAILQ_PREV(var, headname, field)) 452 453 #define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 454 for ((var) = TAILQ_LAST(head, headname); \ 455 (var) != TAILQ_END(head) && \ 456 ((tvar) = TAILQ_PREV(var, headname, field), 1); \ 457 (var) = (tvar)) 458 459 /* 460 * Tail queue functions. 461 */ 462 #define TAILQ_INIT(head) do { \ 463 (head)->tqh_first = NULL; \ 464 (head)->tqh_last = &(head)->tqh_first; \ 465 } while (0) 466 467 #define TAILQ_INSERT_HEAD(head, elm, field) do { \ 468 if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 469 (head)->tqh_first->field.tqe_prev = \ 470 &(elm)->field.tqe_next; \ 471 else \ 472 (head)->tqh_last = &(elm)->field.tqe_next; \ 473 (head)->tqh_first = (elm); \ 474 (elm)->field.tqe_prev = &(head)->tqh_first; \ 475 } while (0) 476 477 #define TAILQ_INSERT_TAIL(head, elm, field) do { \ 478 (elm)->field.tqe_next = NULL; \ 479 (elm)->field.tqe_prev = (head)->tqh_last; \ 480 *(head)->tqh_last = (elm); \ 481 (head)->tqh_last = &(elm)->field.tqe_next; \ 482 } while (0) 483 484 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 485 if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 486 (elm)->field.tqe_next->field.tqe_prev = \ 487 &(elm)->field.tqe_next; \ 488 else \ 489 (head)->tqh_last = &(elm)->field.tqe_next; \ 490 (listelm)->field.tqe_next = (elm); \ 491 (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 492 } while (0) 493 494 #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 495 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 496 (elm)->field.tqe_next = (listelm); \ 497 *(listelm)->field.tqe_prev = (elm); \ 498 (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ 499 } while (0) 500 501 #define TAILQ_REMOVE(head, elm, field) do { \ 502 if (((elm)->field.tqe_next) != NULL) \ 503 (elm)->field.tqe_next->field.tqe_prev = \ 504 (elm)->field.tqe_prev; \ 505 else \ 506 (head)->tqh_last = (elm)->field.tqe_prev; \ 507 *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 508 _Q_INVALIDATE((elm)->field.tqe_prev); \ 509 _Q_INVALIDATE((elm)->field.tqe_next); \ 510 } while (0) 511 512 #define TAILQ_REPLACE(head, elm, elm2, field) do { \ 513 if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ 514 (elm2)->field.tqe_next->field.tqe_prev = \ 515 &(elm2)->field.tqe_next; \ 516 else \ 517 (head)->tqh_last = &(elm2)->field.tqe_next; \ 518 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 519 *(elm2)->field.tqe_prev = (elm2); \ 520 _Q_INVALIDATE((elm)->field.tqe_prev); \ 521 _Q_INVALIDATE((elm)->field.tqe_next); \ 522 } while (0) 523 524 /* 525 * Circular queue definitions. 526 */ 527 #define CIRCLEQ_HEAD(name, type) \ 528 struct name { \ 529 struct type *cqh_first; /* first element */ \ 530 struct type *cqh_last; /* last element */ \ 531 } 532 533 #define CIRCLEQ_HEAD_INITIALIZER(head) \ 534 { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } 535 536 #define CIRCLEQ_ENTRY(type) \ 537 struct { \ 538 struct type *cqe_next; /* next element */ \ 539 struct type *cqe_prev; /* previous element */ \ 540 } 541 542 /* 543 * Circular queue access methods 544 */ 545 #define CIRCLEQ_FIRST(head) ((head)->cqh_first) 546 #define CIRCLEQ_LAST(head) ((head)->cqh_last) 547 #define CIRCLEQ_END(head) ((void *)(head)) 548 #define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) 549 #define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) 550 #define CIRCLEQ_EMPTY(head) \ 551 (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head)) 552 553 #define CIRCLEQ_FOREACH(var, head, field) \ 554 for((var) = CIRCLEQ_FIRST(head); \ 555 (var) != CIRCLEQ_END(head); \ 556 (var) = CIRCLEQ_NEXT(var, field)) 557 558 #define CIRCLEQ_FOREACH_SAFE(var, head, field, tvar) \ 559 for ((var) = CIRCLEQ_FIRST(head); \ 560 (var) != CIRCLEQ_END(head) && \ 561 ((tvar) = CIRCLEQ_NEXT(var, field), 1); \ 562 (var) = (tvar)) 563 564 #define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ 565 for((var) = CIRCLEQ_LAST(head); \ 566 (var) != CIRCLEQ_END(head); \ 567 (var) = CIRCLEQ_PREV(var, field)) 568 569 #define CIRCLEQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 570 for ((var) = CIRCLEQ_LAST(head, headname); \ 571 (var) != CIRCLEQ_END(head) && \ 572 ((tvar) = CIRCLEQ_PREV(var, headname, field), 1); \ 573 (var) = (tvar)) 574 575 /* 576 * Circular queue functions. 577 */ 578 #define CIRCLEQ_INIT(head) do { \ 579 (head)->cqh_first = CIRCLEQ_END(head); \ 580 (head)->cqh_last = CIRCLEQ_END(head); \ 581 } while (0) 582 583 #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 584 (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 585 (elm)->field.cqe_prev = (listelm); \ 586 if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \ 587 (head)->cqh_last = (elm); \ 588 else \ 589 (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 590 (listelm)->field.cqe_next = (elm); \ 591 } while (0) 592 593 #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 594 (elm)->field.cqe_next = (listelm); \ 595 (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 596 if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \ 597 (head)->cqh_first = (elm); \ 598 else \ 599 (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 600 (listelm)->field.cqe_prev = (elm); \ 601 } while (0) 602 603 #define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 604 (elm)->field.cqe_next = (head)->cqh_first; \ 605 (elm)->field.cqe_prev = CIRCLEQ_END(head); \ 606 if ((head)->cqh_last == CIRCLEQ_END(head)) \ 607 (head)->cqh_last = (elm); \ 608 else \ 609 (head)->cqh_first->field.cqe_prev = (elm); \ 610 (head)->cqh_first = (elm); \ 611 } while (0) 612 613 #define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 614 (elm)->field.cqe_next = CIRCLEQ_END(head); \ 615 (elm)->field.cqe_prev = (head)->cqh_last; \ 616 if ((head)->cqh_first == CIRCLEQ_END(head)) \ 617 (head)->cqh_first = (elm); \ 618 else \ 619 (head)->cqh_last->field.cqe_next = (elm); \ 620 (head)->cqh_last = (elm); \ 621 } while (0) 622 623 #define CIRCLEQ_REMOVE(head, elm, field) do { \ 624 if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \ 625 (head)->cqh_last = (elm)->field.cqe_prev; \ 626 else \ 627 (elm)->field.cqe_next->field.cqe_prev = \ 628 (elm)->field.cqe_prev; \ 629 if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \ 630 (head)->cqh_first = (elm)->field.cqe_next; \ 631 else \ 632 (elm)->field.cqe_prev->field.cqe_next = \ 633 (elm)->field.cqe_next; \ 634 _Q_INVALIDATE((elm)->field.cqe_prev); \ 635 _Q_INVALIDATE((elm)->field.cqe_next); \ 636 } while (0) 637 638 #define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \ 639 if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \ 640 CIRCLEQ_END(head)) \ 641 (head).cqh_last = (elm2); \ 642 else \ 643 (elm2)->field.cqe_next->field.cqe_prev = (elm2); \ 644 if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \ 645 CIRCLEQ_END(head)) \ 646 (head).cqh_first = (elm2); \ 647 else \ 648 (elm2)->field.cqe_prev->field.cqe_next = (elm2); \ 649 _Q_INVALIDATE((elm)->field.cqe_prev); \ 650 _Q_INVALIDATE((elm)->field.cqe_next); \ 651 } while (0) 652 653 #endif /* !_FAKE_QUEUE_H_ */ 654