Patrick Williams | d8c66bc | 2016-06-20 12:57:21 -0500 | [diff] [blame] | 1 | /* $NetBSD: queue.h,v 1.68 2014/11/19 08:10:01 uebayasi Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 1991, 1993 |
| 5 | * The Regents of the University of California. All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * 3. Neither the name of the University nor the names of its contributors |
| 16 | * may be used to endorse or promote products derived from this software |
| 17 | * without specific prior written permission. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 29 | * SUCH DAMAGE. |
| 30 | * |
| 31 | * @(#)queue.h 8.5 (Berkeley) 8/20/94 |
| 32 | */ |
| 33 | |
| 34 | #ifndef _SYS_QUEUE_H_ |
| 35 | #define _SYS_QUEUE_H_ |
| 36 | |
| 37 | /* |
| 38 | * This file defines five types of data structures: singly-linked lists, |
| 39 | * lists, simple queues, tail queues, and circular queues. |
| 40 | * |
| 41 | * A singly-linked list is headed by a single forward pointer. The |
| 42 | * elements are singly linked for minimum space and pointer manipulation |
| 43 | * overhead at the expense of O(n) removal for arbitrary elements. New |
| 44 | * elements can be added to the list after an existing element or at the |
| 45 | * head of the list. Elements being removed from the head of the list |
| 46 | * should use the explicit macro for this purpose for optimum |
| 47 | * efficiency. A singly-linked list may only be traversed in the forward |
| 48 | * direction. Singly-linked lists are ideal for applications with large |
| 49 | * datasets and few or no removals or for implementing a LIFO queue. |
| 50 | * |
| 51 | * A list is headed by a single forward pointer (or an array of forward |
| 52 | * pointers for a hash table header). The elements are doubly linked |
| 53 | * so that an arbitrary element can be removed without a need to |
| 54 | * traverse the list. New elements can be added to the list before |
| 55 | * or after an existing element or at the head of the list. A list |
| 56 | * may only be traversed in the forward direction. |
| 57 | * |
| 58 | * A simple queue is headed by a pair of pointers, one the head of the |
| 59 | * list and the other to the tail of the list. The elements are singly |
| 60 | * linked to save space, so elements can only be removed from the |
| 61 | * head of the list. New elements can be added to the list after |
| 62 | * an existing element, at the head of the list, or at the end of the |
| 63 | * list. A simple queue may only be traversed in the forward direction. |
| 64 | * |
| 65 | * A tail queue is headed by a pair of pointers, one to the head of the |
| 66 | * list and the other to the tail of the list. The elements are doubly |
| 67 | * linked so that an arbitrary element can be removed without a need to |
| 68 | * traverse the list. New elements can be added to the list before or |
| 69 | * after an existing element, at the head of the list, or at the end of |
| 70 | * the list. A tail queue may be traversed in either direction. |
| 71 | * |
| 72 | * A circle queue is headed by a pair of pointers, one to the head of the |
| 73 | * list and the other to the tail of the list. The elements are doubly |
| 74 | * linked so that an arbitrary element can be removed without a need to |
| 75 | * traverse the list. New elements can be added to the list before or after |
| 76 | * an existing element, at the head of the list, or at the end of the list. |
| 77 | * A circle queue may be traversed in either direction, but has a more |
| 78 | * complex end of list detection. |
| 79 | * |
| 80 | * For details on the use of these macros, see the queue(3) manual page. |
| 81 | */ |
| 82 | |
| 83 | /* |
| 84 | * Include the definition of NULL only on NetBSD because sys/null.h |
| 85 | * is not available elsewhere. This conditional makes the header |
| 86 | * portable and it can simply be dropped verbatim into any system. |
| 87 | * The caveat is that on other systems some other header |
| 88 | * must provide NULL before the macros can be used. |
| 89 | */ |
| 90 | #ifdef __NetBSD__ |
| 91 | #include <sys/null.h> |
| 92 | #endif |
| 93 | |
| 94 | #if defined(QUEUEDEBUG) |
| 95 | # if defined(_KERNEL) |
| 96 | # define QUEUEDEBUG_ABORT(...) panic(__VA_ARGS__) |
| 97 | # else |
| 98 | # include <err.h> |
| 99 | # define QUEUEDEBUG_ABORT(...) err(1, __VA_ARGS__) |
| 100 | # endif |
| 101 | #endif |
| 102 | |
| 103 | /* |
| 104 | * Singly-linked List definitions. |
| 105 | */ |
| 106 | #define SLIST_HEAD(name, type) \ |
| 107 | struct name { \ |
| 108 | struct type *slh_first; /* first element */ \ |
| 109 | } |
| 110 | |
| 111 | #define SLIST_HEAD_INITIALIZER(head) \ |
| 112 | { NULL } |
| 113 | |
| 114 | #define SLIST_ENTRY(type) \ |
| 115 | struct { \ |
| 116 | struct type *sle_next; /* next element */ \ |
| 117 | } |
| 118 | |
| 119 | /* |
| 120 | * Singly-linked List access methods. |
| 121 | */ |
| 122 | #define SLIST_FIRST(head) ((head)->slh_first) |
| 123 | #define SLIST_END(head) NULL |
| 124 | #define SLIST_EMPTY(head) ((head)->slh_first == NULL) |
| 125 | #define SLIST_NEXT(elm, field) ((elm)->field.sle_next) |
| 126 | |
| 127 | #define SLIST_FOREACH(var, head, field) \ |
| 128 | for((var) = (head)->slh_first; \ |
| 129 | (var) != SLIST_END(head); \ |
| 130 | (var) = (var)->field.sle_next) |
| 131 | |
| 132 | #define SLIST_FOREACH_SAFE(var, head, field, tvar) \ |
| 133 | for ((var) = SLIST_FIRST((head)); \ |
| 134 | (var) != SLIST_END(head) && \ |
| 135 | ((tvar) = SLIST_NEXT((var), field), 1); \ |
| 136 | (var) = (tvar)) |
| 137 | |
| 138 | /* |
| 139 | * Singly-linked List functions. |
| 140 | */ |
| 141 | #define SLIST_INIT(head) do { \ |
| 142 | (head)->slh_first = SLIST_END(head); \ |
| 143 | } while (/*CONSTCOND*/0) |
| 144 | |
| 145 | #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ |
| 146 | (elm)->field.sle_next = (slistelm)->field.sle_next; \ |
| 147 | (slistelm)->field.sle_next = (elm); \ |
| 148 | } while (/*CONSTCOND*/0) |
| 149 | |
| 150 | #define SLIST_INSERT_HEAD(head, elm, field) do { \ |
| 151 | (elm)->field.sle_next = (head)->slh_first; \ |
| 152 | (head)->slh_first = (elm); \ |
| 153 | } while (/*CONSTCOND*/0) |
| 154 | |
| 155 | #define SLIST_REMOVE_AFTER(slistelm, field) do { \ |
| 156 | (slistelm)->field.sle_next = \ |
| 157 | SLIST_NEXT(SLIST_NEXT((slistelm), field), field); \ |
| 158 | } while (/*CONSTCOND*/0) |
| 159 | |
| 160 | #define SLIST_REMOVE_HEAD(head, field) do { \ |
| 161 | (head)->slh_first = (head)->slh_first->field.sle_next; \ |
| 162 | } while (/*CONSTCOND*/0) |
| 163 | |
| 164 | #define SLIST_REMOVE(head, elm, type, field) do { \ |
| 165 | if ((head)->slh_first == (elm)) { \ |
| 166 | SLIST_REMOVE_HEAD((head), field); \ |
| 167 | } \ |
| 168 | else { \ |
| 169 | struct type *curelm = (head)->slh_first; \ |
| 170 | while(curelm->field.sle_next != (elm)) \ |
| 171 | curelm = curelm->field.sle_next; \ |
| 172 | curelm->field.sle_next = \ |
| 173 | curelm->field.sle_next->field.sle_next; \ |
| 174 | } \ |
| 175 | } while (/*CONSTCOND*/0) |
| 176 | |
| 177 | |
| 178 | /* |
| 179 | * List definitions. |
| 180 | */ |
| 181 | #define LIST_HEAD(name, type) \ |
| 182 | struct name { \ |
| 183 | struct type *lh_first; /* first element */ \ |
| 184 | } |
| 185 | |
| 186 | #define LIST_HEAD_INITIALIZER(head) \ |
| 187 | { NULL } |
| 188 | |
| 189 | #define LIST_ENTRY(type) \ |
| 190 | struct { \ |
| 191 | struct type *le_next; /* next element */ \ |
| 192 | struct type **le_prev; /* address of previous next element */ \ |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * List access methods. |
| 197 | */ |
| 198 | #define LIST_FIRST(head) ((head)->lh_first) |
| 199 | #define LIST_END(head) NULL |
| 200 | #define LIST_EMPTY(head) ((head)->lh_first == LIST_END(head)) |
| 201 | #define LIST_NEXT(elm, field) ((elm)->field.le_next) |
| 202 | |
| 203 | #define LIST_FOREACH(var, head, field) \ |
| 204 | for ((var) = ((head)->lh_first); \ |
| 205 | (var) != LIST_END(head); \ |
| 206 | (var) = ((var)->field.le_next)) |
| 207 | |
| 208 | #define LIST_FOREACH_SAFE(var, head, field, tvar) \ |
| 209 | for ((var) = LIST_FIRST((head)); \ |
| 210 | (var) != LIST_END(head) && \ |
| 211 | ((tvar) = LIST_NEXT((var), field), 1); \ |
| 212 | (var) = (tvar)) |
| 213 | |
| 214 | #define LIST_MOVE(head1, head2) do { \ |
| 215 | LIST_INIT((head2)); \ |
| 216 | if (!LIST_EMPTY((head1))) { \ |
| 217 | (head2)->lh_first = (head1)->lh_first; \ |
| 218 | LIST_INIT((head1)); \ |
| 219 | } \ |
| 220 | } while (/*CONSTCOND*/0) |
| 221 | |
| 222 | /* |
| 223 | * List functions. |
| 224 | */ |
| 225 | #if defined(QUEUEDEBUG) |
| 226 | #define QUEUEDEBUG_LIST_INSERT_HEAD(head, elm, field) \ |
| 227 | if ((head)->lh_first && \ |
| 228 | (head)->lh_first->field.le_prev != &(head)->lh_first) \ |
| 229 | QUEUEDEBUG_ABORT("LIST_INSERT_HEAD %p %s:%d", (head), \ |
| 230 | __FILE__, __LINE__); |
| 231 | #define QUEUEDEBUG_LIST_OP(elm, field) \ |
| 232 | if ((elm)->field.le_next && \ |
| 233 | (elm)->field.le_next->field.le_prev != \ |
| 234 | &(elm)->field.le_next) \ |
| 235 | QUEUEDEBUG_ABORT("LIST_* forw %p %s:%d", (elm), \ |
| 236 | __FILE__, __LINE__); \ |
| 237 | if (*(elm)->field.le_prev != (elm)) \ |
| 238 | QUEUEDEBUG_ABORT("LIST_* back %p %s:%d", (elm), \ |
| 239 | __FILE__, __LINE__); |
| 240 | #define QUEUEDEBUG_LIST_POSTREMOVE(elm, field) \ |
| 241 | (elm)->field.le_next = (void *)1L; \ |
| 242 | (elm)->field.le_prev = (void *)1L; |
| 243 | #else |
| 244 | #define QUEUEDEBUG_LIST_INSERT_HEAD(head, elm, field) |
| 245 | #define QUEUEDEBUG_LIST_OP(elm, field) |
| 246 | #define QUEUEDEBUG_LIST_POSTREMOVE(elm, field) |
| 247 | #endif |
| 248 | |
| 249 | #define LIST_INIT(head) do { \ |
| 250 | (head)->lh_first = LIST_END(head); \ |
| 251 | } while (/*CONSTCOND*/0) |
| 252 | |
| 253 | #define LIST_INSERT_AFTER(listelm, elm, field) do { \ |
| 254 | QUEUEDEBUG_LIST_OP((listelm), field) \ |
| 255 | if (((elm)->field.le_next = (listelm)->field.le_next) != \ |
| 256 | LIST_END(head)) \ |
| 257 | (listelm)->field.le_next->field.le_prev = \ |
| 258 | &(elm)->field.le_next; \ |
| 259 | (listelm)->field.le_next = (elm); \ |
| 260 | (elm)->field.le_prev = &(listelm)->field.le_next; \ |
| 261 | } while (/*CONSTCOND*/0) |
| 262 | |
| 263 | #define LIST_INSERT_BEFORE(listelm, elm, field) do { \ |
| 264 | QUEUEDEBUG_LIST_OP((listelm), field) \ |
| 265 | (elm)->field.le_prev = (listelm)->field.le_prev; \ |
| 266 | (elm)->field.le_next = (listelm); \ |
| 267 | *(listelm)->field.le_prev = (elm); \ |
| 268 | (listelm)->field.le_prev = &(elm)->field.le_next; \ |
| 269 | } while (/*CONSTCOND*/0) |
| 270 | |
| 271 | #define LIST_INSERT_HEAD(head, elm, field) do { \ |
| 272 | QUEUEDEBUG_LIST_INSERT_HEAD((head), (elm), field) \ |
| 273 | if (((elm)->field.le_next = (head)->lh_first) != LIST_END(head))\ |
| 274 | (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ |
| 275 | (head)->lh_first = (elm); \ |
| 276 | (elm)->field.le_prev = &(head)->lh_first; \ |
| 277 | } while (/*CONSTCOND*/0) |
| 278 | |
| 279 | #define LIST_REMOVE(elm, field) do { \ |
| 280 | QUEUEDEBUG_LIST_OP((elm), field) \ |
| 281 | if ((elm)->field.le_next != NULL) \ |
| 282 | (elm)->field.le_next->field.le_prev = \ |
| 283 | (elm)->field.le_prev; \ |
| 284 | *(elm)->field.le_prev = (elm)->field.le_next; \ |
| 285 | QUEUEDEBUG_LIST_POSTREMOVE((elm), field) \ |
| 286 | } while (/*CONSTCOND*/0) |
| 287 | |
| 288 | #define LIST_REPLACE(elm, elm2, field) do { \ |
| 289 | if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ |
| 290 | (elm2)->field.le_next->field.le_prev = \ |
| 291 | &(elm2)->field.le_next; \ |
| 292 | (elm2)->field.le_prev = (elm)->field.le_prev; \ |
| 293 | *(elm2)->field.le_prev = (elm2); \ |
| 294 | QUEUEDEBUG_LIST_POSTREMOVE((elm), field) \ |
| 295 | } while (/*CONSTCOND*/0) |
| 296 | |
| 297 | /* |
| 298 | * Simple queue definitions. |
| 299 | */ |
| 300 | #define SIMPLEQ_HEAD(name, type) \ |
| 301 | struct name { \ |
| 302 | struct type *sqh_first; /* first element */ \ |
| 303 | struct type **sqh_last; /* addr of last next element */ \ |
| 304 | } |
| 305 | |
| 306 | #define SIMPLEQ_HEAD_INITIALIZER(head) \ |
| 307 | { NULL, &(head).sqh_first } |
| 308 | |
| 309 | #define SIMPLEQ_ENTRY(type) \ |
| 310 | struct { \ |
| 311 | struct type *sqe_next; /* next element */ \ |
| 312 | } |
| 313 | |
| 314 | /* |
| 315 | * Simple queue access methods. |
| 316 | */ |
| 317 | #define SIMPLEQ_FIRST(head) ((head)->sqh_first) |
| 318 | #define SIMPLEQ_END(head) NULL |
| 319 | #define SIMPLEQ_EMPTY(head) ((head)->sqh_first == SIMPLEQ_END(head)) |
| 320 | #define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) |
| 321 | |
| 322 | #define SIMPLEQ_FOREACH(var, head, field) \ |
| 323 | for ((var) = ((head)->sqh_first); \ |
| 324 | (var) != SIMPLEQ_END(head); \ |
| 325 | (var) = ((var)->field.sqe_next)) |
| 326 | |
| 327 | #define SIMPLEQ_FOREACH_SAFE(var, head, field, next) \ |
| 328 | for ((var) = ((head)->sqh_first); \ |
| 329 | (var) != SIMPLEQ_END(head) && \ |
| 330 | ((next = ((var)->field.sqe_next)), 1); \ |
| 331 | (var) = (next)) |
| 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 (/*CONSTCOND*/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 (/*CONSTCOND*/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 (/*CONSTCOND*/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 (/*CONSTCOND*/0) |
| 358 | |
| 359 | #define SIMPLEQ_REMOVE_HEAD(head, field) do { \ |
| 360 | if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \ |
| 361 | (head)->sqh_last = &(head)->sqh_first; \ |
| 362 | } while (/*CONSTCOND*/0) |
| 363 | |
| 364 | #define SIMPLEQ_REMOVE_AFTER(head, elm, field) do { \ |
| 365 | if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \ |
| 366 | == NULL) \ |
| 367 | (head)->sqh_last = &(elm)->field.sqe_next; \ |
| 368 | } while (/*CONSTCOND*/0) |
| 369 | |
| 370 | #define SIMPLEQ_REMOVE(head, elm, type, field) do { \ |
| 371 | if ((head)->sqh_first == (elm)) { \ |
| 372 | SIMPLEQ_REMOVE_HEAD((head), field); \ |
| 373 | } else { \ |
| 374 | struct type *curelm = (head)->sqh_first; \ |
| 375 | while (curelm->field.sqe_next != (elm)) \ |
| 376 | curelm = curelm->field.sqe_next; \ |
| 377 | if ((curelm->field.sqe_next = \ |
| 378 | curelm->field.sqe_next->field.sqe_next) == NULL) \ |
| 379 | (head)->sqh_last = &(curelm)->field.sqe_next; \ |
| 380 | } \ |
| 381 | } while (/*CONSTCOND*/0) |
| 382 | |
| 383 | #define SIMPLEQ_CONCAT(head1, head2) do { \ |
| 384 | if (!SIMPLEQ_EMPTY((head2))) { \ |
| 385 | *(head1)->sqh_last = (head2)->sqh_first; \ |
| 386 | (head1)->sqh_last = (head2)->sqh_last; \ |
| 387 | SIMPLEQ_INIT((head2)); \ |
| 388 | } \ |
| 389 | } while (/*CONSTCOND*/0) |
| 390 | |
| 391 | #define SIMPLEQ_LAST(head, type, field) \ |
| 392 | (SIMPLEQ_EMPTY((head)) ? \ |
| 393 | NULL : \ |
| 394 | ((struct type *)(void *) \ |
| 395 | ((char *)((head)->sqh_last) - offsetof(struct type, field)))) |
| 396 | |
| 397 | /* |
| 398 | * Tail queue definitions. |
| 399 | */ |
| 400 | #define _TAILQ_HEAD(name, type, qual) \ |
| 401 | struct name { \ |
| 402 | qual type *tqh_first; /* first element */ \ |
| 403 | qual type *qual *tqh_last; /* addr of last next element */ \ |
| 404 | } |
| 405 | #define TAILQ_HEAD(name, type) _TAILQ_HEAD(name, struct type,) |
| 406 | |
| 407 | #define TAILQ_HEAD_INITIALIZER(head) \ |
| 408 | { TAILQ_END(head), &(head).tqh_first } |
| 409 | |
| 410 | #define _TAILQ_ENTRY(type, qual) \ |
| 411 | struct { \ |
| 412 | qual type *tqe_next; /* next element */ \ |
| 413 | qual type *qual *tqe_prev; /* address of previous next element */\ |
| 414 | } |
| 415 | #define TAILQ_ENTRY(type) _TAILQ_ENTRY(struct type,) |
| 416 | |
| 417 | /* |
| 418 | * Tail queue access methods. |
| 419 | */ |
| 420 | #define TAILQ_FIRST(head) ((head)->tqh_first) |
| 421 | #define TAILQ_END(head) (NULL) |
| 422 | #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) |
| 423 | #define TAILQ_LAST(head, headname) \ |
| 424 | (*(((struct headname *)((head)->tqh_last))->tqh_last)) |
| 425 | #define TAILQ_PREV(elm, headname, field) \ |
| 426 | (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) |
| 427 | #define TAILQ_EMPTY(head) (TAILQ_FIRST(head) == TAILQ_END(head)) |
| 428 | |
| 429 | |
| 430 | #define TAILQ_FOREACH(var, head, field) \ |
| 431 | for ((var) = ((head)->tqh_first); \ |
| 432 | (var) != TAILQ_END(head); \ |
| 433 | (var) = ((var)->field.tqe_next)) |
| 434 | |
| 435 | #define TAILQ_FOREACH_SAFE(var, head, field, next) \ |
| 436 | for ((var) = ((head)->tqh_first); \ |
| 437 | (var) != TAILQ_END(head) && \ |
| 438 | ((next) = TAILQ_NEXT(var, field), 1); (var) = (next)) |
| 439 | |
| 440 | #define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ |
| 441 | for ((var) = (*(((struct headname *)((head)->tqh_last))->tqh_last));\ |
| 442 | (var) != TAILQ_END(head); \ |
| 443 | (var) = (*(((struct headname *)((var)->field.tqe_prev))->tqh_last))) |
| 444 | |
| 445 | #define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, prev) \ |
| 446 | for ((var) = TAILQ_LAST((head), headname); \ |
| 447 | (var) != TAILQ_END(head) && \ |
| 448 | ((prev) = TAILQ_PREV((var), headname, field), 1); (var) = (prev)) |
| 449 | |
| 450 | /* |
| 451 | * Tail queue functions. |
| 452 | */ |
| 453 | #if defined(QUEUEDEBUG) |
| 454 | #define QUEUEDEBUG_TAILQ_INSERT_HEAD(head, elm, field) \ |
| 455 | if ((head)->tqh_first && \ |
| 456 | (head)->tqh_first->field.tqe_prev != &(head)->tqh_first) \ |
| 457 | QUEUEDEBUG_ABORT("TAILQ_INSERT_HEAD %p %s:%d", (head), \ |
| 458 | __FILE__, __LINE__); |
| 459 | #define QUEUEDEBUG_TAILQ_INSERT_TAIL(head, elm, field) \ |
| 460 | if (*(head)->tqh_last != NULL) \ |
| 461 | QUEUEDEBUG_ABORT("TAILQ_INSERT_TAIL %p %s:%d", (head), \ |
| 462 | __FILE__, __LINE__); |
| 463 | #define QUEUEDEBUG_TAILQ_OP(elm, field) \ |
| 464 | if ((elm)->field.tqe_next && \ |
| 465 | (elm)->field.tqe_next->field.tqe_prev != \ |
| 466 | &(elm)->field.tqe_next) \ |
| 467 | QUEUEDEBUG_ABORT("TAILQ_* forw %p %s:%d", (elm), \ |
| 468 | __FILE__, __LINE__); \ |
| 469 | if (*(elm)->field.tqe_prev != (elm)) \ |
| 470 | QUEUEDEBUG_ABORT("TAILQ_* back %p %s:%d", (elm), \ |
| 471 | __FILE__, __LINE__); |
| 472 | #define QUEUEDEBUG_TAILQ_PREREMOVE(head, elm, field) \ |
| 473 | if ((elm)->field.tqe_next == NULL && \ |
| 474 | (head)->tqh_last != &(elm)->field.tqe_next) \ |
| 475 | QUEUEDEBUG_ABORT("TAILQ_PREREMOVE head %p elm %p %s:%d",\ |
| 476 | (head), (elm), __FILE__, __LINE__); |
| 477 | #define QUEUEDEBUG_TAILQ_POSTREMOVE(elm, field) \ |
| 478 | (elm)->field.tqe_next = (void *)1L; \ |
| 479 | (elm)->field.tqe_prev = (void *)1L; |
| 480 | #else |
| 481 | #define QUEUEDEBUG_TAILQ_INSERT_HEAD(head, elm, field) |
| 482 | #define QUEUEDEBUG_TAILQ_INSERT_TAIL(head, elm, field) |
| 483 | #define QUEUEDEBUG_TAILQ_OP(elm, field) |
| 484 | #define QUEUEDEBUG_TAILQ_PREREMOVE(head, elm, field) |
| 485 | #define QUEUEDEBUG_TAILQ_POSTREMOVE(elm, field) |
| 486 | #endif |
| 487 | |
| 488 | #define TAILQ_INIT(head) do { \ |
| 489 | (head)->tqh_first = TAILQ_END(head); \ |
| 490 | (head)->tqh_last = &(head)->tqh_first; \ |
| 491 | } while (/*CONSTCOND*/0) |
| 492 | |
| 493 | #define TAILQ_INSERT_HEAD(head, elm, field) do { \ |
| 494 | QUEUEDEBUG_TAILQ_INSERT_HEAD((head), (elm), field) \ |
| 495 | if (((elm)->field.tqe_next = (head)->tqh_first) != TAILQ_END(head))\ |
| 496 | (head)->tqh_first->field.tqe_prev = \ |
| 497 | &(elm)->field.tqe_next; \ |
| 498 | else \ |
| 499 | (head)->tqh_last = &(elm)->field.tqe_next; \ |
| 500 | (head)->tqh_first = (elm); \ |
| 501 | (elm)->field.tqe_prev = &(head)->tqh_first; \ |
| 502 | } while (/*CONSTCOND*/0) |
| 503 | |
| 504 | #define TAILQ_INSERT_TAIL(head, elm, field) do { \ |
| 505 | QUEUEDEBUG_TAILQ_INSERT_TAIL((head), (elm), field) \ |
| 506 | (elm)->field.tqe_next = TAILQ_END(head); \ |
| 507 | (elm)->field.tqe_prev = (head)->tqh_last; \ |
| 508 | *(head)->tqh_last = (elm); \ |
| 509 | (head)->tqh_last = &(elm)->field.tqe_next; \ |
| 510 | } while (/*CONSTCOND*/0) |
| 511 | |
| 512 | #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ |
| 513 | QUEUEDEBUG_TAILQ_OP((listelm), field) \ |
| 514 | if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != \ |
| 515 | TAILQ_END(head)) \ |
| 516 | (elm)->field.tqe_next->field.tqe_prev = \ |
| 517 | &(elm)->field.tqe_next; \ |
| 518 | else \ |
| 519 | (head)->tqh_last = &(elm)->field.tqe_next; \ |
| 520 | (listelm)->field.tqe_next = (elm); \ |
| 521 | (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ |
| 522 | } while (/*CONSTCOND*/0) |
| 523 | |
| 524 | #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ |
| 525 | QUEUEDEBUG_TAILQ_OP((listelm), field) \ |
| 526 | (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ |
| 527 | (elm)->field.tqe_next = (listelm); \ |
| 528 | *(listelm)->field.tqe_prev = (elm); \ |
| 529 | (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ |
| 530 | } while (/*CONSTCOND*/0) |
| 531 | |
| 532 | #define TAILQ_REMOVE(head, elm, field) do { \ |
| 533 | QUEUEDEBUG_TAILQ_PREREMOVE((head), (elm), field) \ |
| 534 | QUEUEDEBUG_TAILQ_OP((elm), field) \ |
| 535 | if (((elm)->field.tqe_next) != TAILQ_END(head)) \ |
| 536 | (elm)->field.tqe_next->field.tqe_prev = \ |
| 537 | (elm)->field.tqe_prev; \ |
| 538 | else \ |
| 539 | (head)->tqh_last = (elm)->field.tqe_prev; \ |
| 540 | *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ |
| 541 | QUEUEDEBUG_TAILQ_POSTREMOVE((elm), field); \ |
| 542 | } while (/*CONSTCOND*/0) |
| 543 | |
| 544 | #define TAILQ_REPLACE(head, elm, elm2, field) do { \ |
| 545 | if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != \ |
| 546 | TAILQ_END(head)) \ |
| 547 | (elm2)->field.tqe_next->field.tqe_prev = \ |
| 548 | &(elm2)->field.tqe_next; \ |
| 549 | else \ |
| 550 | (head)->tqh_last = &(elm2)->field.tqe_next; \ |
| 551 | (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ |
| 552 | *(elm2)->field.tqe_prev = (elm2); \ |
| 553 | QUEUEDEBUG_TAILQ_POSTREMOVE((elm), field); \ |
| 554 | } while (/*CONSTCOND*/0) |
| 555 | |
| 556 | #define TAILQ_CONCAT(head1, head2, field) do { \ |
| 557 | if (!TAILQ_EMPTY(head2)) { \ |
| 558 | *(head1)->tqh_last = (head2)->tqh_first; \ |
| 559 | (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ |
| 560 | (head1)->tqh_last = (head2)->tqh_last; \ |
| 561 | TAILQ_INIT((head2)); \ |
| 562 | } \ |
| 563 | } while (/*CONSTCOND*/0) |
| 564 | |
| 565 | /* |
| 566 | * Singly-linked Tail queue declarations. |
| 567 | */ |
| 568 | #define STAILQ_HEAD(name, type) \ |
| 569 | struct name { \ |
| 570 | struct type *stqh_first; /* first element */ \ |
| 571 | struct type **stqh_last; /* addr of last next element */ \ |
| 572 | } |
| 573 | |
| 574 | #define STAILQ_HEAD_INITIALIZER(head) \ |
| 575 | { NULL, &(head).stqh_first } |
| 576 | |
| 577 | #define STAILQ_ENTRY(type) \ |
| 578 | struct { \ |
| 579 | struct type *stqe_next; /* next element */ \ |
| 580 | } |
| 581 | |
| 582 | /* |
| 583 | * Singly-linked Tail queue access methods. |
| 584 | */ |
| 585 | #define STAILQ_FIRST(head) ((head)->stqh_first) |
| 586 | #define STAILQ_END(head) NULL |
| 587 | #define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) |
| 588 | #define STAILQ_EMPTY(head) (STAILQ_FIRST(head) == STAILQ_END(head)) |
| 589 | |
| 590 | /* |
| 591 | * Singly-linked Tail queue functions. |
| 592 | */ |
| 593 | #define STAILQ_INIT(head) do { \ |
| 594 | (head)->stqh_first = NULL; \ |
| 595 | (head)->stqh_last = &(head)->stqh_first; \ |
| 596 | } while (/*CONSTCOND*/0) |
| 597 | |
| 598 | #define STAILQ_INSERT_HEAD(head, elm, field) do { \ |
| 599 | if (((elm)->field.stqe_next = (head)->stqh_first) == NULL) \ |
| 600 | (head)->stqh_last = &(elm)->field.stqe_next; \ |
| 601 | (head)->stqh_first = (elm); \ |
| 602 | } while (/*CONSTCOND*/0) |
| 603 | |
| 604 | #define STAILQ_INSERT_TAIL(head, elm, field) do { \ |
| 605 | (elm)->field.stqe_next = NULL; \ |
| 606 | *(head)->stqh_last = (elm); \ |
| 607 | (head)->stqh_last = &(elm)->field.stqe_next; \ |
| 608 | } while (/*CONSTCOND*/0) |
| 609 | |
| 610 | #define STAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ |
| 611 | if (((elm)->field.stqe_next = (listelm)->field.stqe_next) == NULL)\ |
| 612 | (head)->stqh_last = &(elm)->field.stqe_next; \ |
| 613 | (listelm)->field.stqe_next = (elm); \ |
| 614 | } while (/*CONSTCOND*/0) |
| 615 | |
| 616 | #define STAILQ_REMOVE_HEAD(head, field) do { \ |
| 617 | if (((head)->stqh_first = (head)->stqh_first->field.stqe_next) == NULL) \ |
| 618 | (head)->stqh_last = &(head)->stqh_first; \ |
| 619 | } while (/*CONSTCOND*/0) |
| 620 | |
| 621 | #define STAILQ_REMOVE(head, elm, type, field) do { \ |
| 622 | if ((head)->stqh_first == (elm)) { \ |
| 623 | STAILQ_REMOVE_HEAD((head), field); \ |
| 624 | } else { \ |
| 625 | struct type *curelm = (head)->stqh_first; \ |
| 626 | while (curelm->field.stqe_next != (elm)) \ |
| 627 | curelm = curelm->field.stqe_next; \ |
| 628 | if ((curelm->field.stqe_next = \ |
| 629 | curelm->field.stqe_next->field.stqe_next) == NULL) \ |
| 630 | (head)->stqh_last = &(curelm)->field.stqe_next; \ |
| 631 | } \ |
| 632 | } while (/*CONSTCOND*/0) |
| 633 | |
| 634 | #define STAILQ_FOREACH(var, head, field) \ |
| 635 | for ((var) = ((head)->stqh_first); \ |
| 636 | (var); \ |
| 637 | (var) = ((var)->field.stqe_next)) |
| 638 | |
| 639 | #define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ |
| 640 | for ((var) = STAILQ_FIRST((head)); \ |
| 641 | (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ |
| 642 | (var) = (tvar)) |
| 643 | |
| 644 | #define STAILQ_CONCAT(head1, head2) do { \ |
| 645 | if (!STAILQ_EMPTY((head2))) { \ |
| 646 | *(head1)->stqh_last = (head2)->stqh_first; \ |
| 647 | (head1)->stqh_last = (head2)->stqh_last; \ |
| 648 | STAILQ_INIT((head2)); \ |
| 649 | } \ |
| 650 | } while (/*CONSTCOND*/0) |
| 651 | |
| 652 | #define STAILQ_LAST(head, type, field) \ |
| 653 | (STAILQ_EMPTY((head)) ? \ |
| 654 | NULL : \ |
| 655 | ((struct type *)(void *) \ |
| 656 | ((char *)((head)->stqh_last) - offsetof(struct type, field)))) |
| 657 | |
| 658 | |
| 659 | #ifndef _KERNEL |
| 660 | /* |
| 661 | * Circular queue definitions. Do not use. We still keep the macros |
| 662 | * for compatibility but because of pointer aliasing issues their use |
| 663 | * is discouraged! |
| 664 | */ |
| 665 | |
| 666 | /* |
| 667 | * __launder_type(): We use this ugly hack to work around the the compiler |
| 668 | * noticing that two types may not alias each other and elide tests in code. |
| 669 | * We hit this in the CIRCLEQ macros when comparing 'struct name *' and |
| 670 | * 'struct type *' (see CIRCLEQ_HEAD()). Modern compilers (such as GCC |
| 671 | * 4.8) declare these comparisons as always false, causing the code to |
| 672 | * not run as designed. |
| 673 | * |
| 674 | * This hack is only to be used for comparisons and thus can be fully const. |
| 675 | * Do not use for assignment. |
| 676 | * |
| 677 | * If we ever choose to change the ABI of the CIRCLEQ macros, we could fix |
| 678 | * this by changing the head/tail sentinal values, but see the note above |
| 679 | * this one. |
| 680 | */ |
| 681 | static __inline const void * __launder_type(const void *); |
| 682 | static __inline const void * |
| 683 | __launder_type(const void *__x) |
| 684 | { |
| 685 | __asm __volatile("" : "+r" (__x)); |
| 686 | return __x; |
| 687 | } |
| 688 | |
| 689 | #if defined(QUEUEDEBUG) |
| 690 | #define QUEUEDEBUG_CIRCLEQ_HEAD(head, field) \ |
| 691 | if ((head)->cqh_first != CIRCLEQ_ENDC(head) && \ |
| 692 | (head)->cqh_first->field.cqe_prev != CIRCLEQ_ENDC(head)) \ |
| 693 | QUEUEDEBUG_ABORT("CIRCLEQ head forw %p %s:%d", (head), \ |
| 694 | __FILE__, __LINE__); \ |
| 695 | if ((head)->cqh_last != CIRCLEQ_ENDC(head) && \ |
| 696 | (head)->cqh_last->field.cqe_next != CIRCLEQ_ENDC(head)) \ |
| 697 | QUEUEDEBUG_ABORT("CIRCLEQ head back %p %s:%d", (head), \ |
| 698 | __FILE__, __LINE__); |
| 699 | #define QUEUEDEBUG_CIRCLEQ_ELM(head, elm, field) \ |
| 700 | if ((elm)->field.cqe_next == CIRCLEQ_ENDC(head)) { \ |
| 701 | if ((head)->cqh_last != (elm)) \ |
| 702 | QUEUEDEBUG_ABORT("CIRCLEQ elm last %p %s:%d", \ |
| 703 | (elm), __FILE__, __LINE__); \ |
| 704 | } else { \ |
| 705 | if ((elm)->field.cqe_next->field.cqe_prev != (elm)) \ |
| 706 | QUEUEDEBUG_ABORT("CIRCLEQ elm forw %p %s:%d", \ |
| 707 | (elm), __FILE__, __LINE__); \ |
| 708 | } \ |
| 709 | if ((elm)->field.cqe_prev == CIRCLEQ_ENDC(head)) { \ |
| 710 | if ((head)->cqh_first != (elm)) \ |
| 711 | QUEUEDEBUG_ABORT("CIRCLEQ elm first %p %s:%d", \ |
| 712 | (elm), __FILE__, __LINE__); \ |
| 713 | } else { \ |
| 714 | if ((elm)->field.cqe_prev->field.cqe_next != (elm)) \ |
| 715 | QUEUEDEBUG_ABORT("CIRCLEQ elm prev %p %s:%d", \ |
| 716 | (elm), __FILE__, __LINE__); \ |
| 717 | } |
| 718 | #define QUEUEDEBUG_CIRCLEQ_POSTREMOVE(elm, field) \ |
| 719 | (elm)->field.cqe_next = (void *)1L; \ |
| 720 | (elm)->field.cqe_prev = (void *)1L; |
| 721 | #else |
| 722 | #define QUEUEDEBUG_CIRCLEQ_HEAD(head, field) |
| 723 | #define QUEUEDEBUG_CIRCLEQ_ELM(head, elm, field) |
| 724 | #define QUEUEDEBUG_CIRCLEQ_POSTREMOVE(elm, field) |
| 725 | #endif |
| 726 | |
| 727 | #define CIRCLEQ_HEAD(name, type) \ |
| 728 | struct name { \ |
| 729 | struct type *cqh_first; /* first element */ \ |
| 730 | struct type *cqh_last; /* last element */ \ |
| 731 | } |
| 732 | |
| 733 | #define CIRCLEQ_HEAD_INITIALIZER(head) \ |
| 734 | { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } |
| 735 | |
| 736 | #define CIRCLEQ_ENTRY(type) \ |
| 737 | struct { \ |
| 738 | struct type *cqe_next; /* next element */ \ |
| 739 | struct type *cqe_prev; /* previous element */ \ |
| 740 | } |
| 741 | |
| 742 | /* |
| 743 | * Circular queue functions. |
| 744 | */ |
| 745 | #define CIRCLEQ_INIT(head) do { \ |
| 746 | (head)->cqh_first = CIRCLEQ_END(head); \ |
| 747 | (head)->cqh_last = CIRCLEQ_END(head); \ |
| 748 | } while (/*CONSTCOND*/0) |
| 749 | |
| 750 | #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ |
| 751 | QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \ |
| 752 | QUEUEDEBUG_CIRCLEQ_ELM((head), (listelm), field) \ |
| 753 | (elm)->field.cqe_next = (listelm)->field.cqe_next; \ |
| 754 | (elm)->field.cqe_prev = (listelm); \ |
| 755 | if ((listelm)->field.cqe_next == CIRCLEQ_ENDC(head)) \ |
| 756 | (head)->cqh_last = (elm); \ |
| 757 | else \ |
| 758 | (listelm)->field.cqe_next->field.cqe_prev = (elm); \ |
| 759 | (listelm)->field.cqe_next = (elm); \ |
| 760 | } while (/*CONSTCOND*/0) |
| 761 | |
| 762 | #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ |
| 763 | QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \ |
| 764 | QUEUEDEBUG_CIRCLEQ_ELM((head), (listelm), field) \ |
| 765 | (elm)->field.cqe_next = (listelm); \ |
| 766 | (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ |
| 767 | if ((listelm)->field.cqe_prev == CIRCLEQ_ENDC(head)) \ |
| 768 | (head)->cqh_first = (elm); \ |
| 769 | else \ |
| 770 | (listelm)->field.cqe_prev->field.cqe_next = (elm); \ |
| 771 | (listelm)->field.cqe_prev = (elm); \ |
| 772 | } while (/*CONSTCOND*/0) |
| 773 | |
| 774 | #define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ |
| 775 | QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \ |
| 776 | (elm)->field.cqe_next = (head)->cqh_first; \ |
| 777 | (elm)->field.cqe_prev = CIRCLEQ_END(head); \ |
| 778 | if ((head)->cqh_last == CIRCLEQ_ENDC(head)) \ |
| 779 | (head)->cqh_last = (elm); \ |
| 780 | else \ |
| 781 | (head)->cqh_first->field.cqe_prev = (elm); \ |
| 782 | (head)->cqh_first = (elm); \ |
| 783 | } while (/*CONSTCOND*/0) |
| 784 | |
| 785 | #define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ |
| 786 | QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \ |
| 787 | (elm)->field.cqe_next = CIRCLEQ_END(head); \ |
| 788 | (elm)->field.cqe_prev = (head)->cqh_last; \ |
| 789 | if ((head)->cqh_first == CIRCLEQ_ENDC(head)) \ |
| 790 | (head)->cqh_first = (elm); \ |
| 791 | else \ |
| 792 | (head)->cqh_last->field.cqe_next = (elm); \ |
| 793 | (head)->cqh_last = (elm); \ |
| 794 | } while (/*CONSTCOND*/0) |
| 795 | |
| 796 | #define CIRCLEQ_REMOVE(head, elm, field) do { \ |
| 797 | QUEUEDEBUG_CIRCLEQ_HEAD((head), field) \ |
| 798 | QUEUEDEBUG_CIRCLEQ_ELM((head), (elm), field) \ |
| 799 | if ((elm)->field.cqe_next == CIRCLEQ_ENDC(head)) \ |
| 800 | (head)->cqh_last = (elm)->field.cqe_prev; \ |
| 801 | else \ |
| 802 | (elm)->field.cqe_next->field.cqe_prev = \ |
| 803 | (elm)->field.cqe_prev; \ |
| 804 | if ((elm)->field.cqe_prev == CIRCLEQ_ENDC(head)) \ |
| 805 | (head)->cqh_first = (elm)->field.cqe_next; \ |
| 806 | else \ |
| 807 | (elm)->field.cqe_prev->field.cqe_next = \ |
| 808 | (elm)->field.cqe_next; \ |
| 809 | QUEUEDEBUG_CIRCLEQ_POSTREMOVE((elm), field) \ |
| 810 | } while (/*CONSTCOND*/0) |
| 811 | |
| 812 | #define CIRCLEQ_FOREACH(var, head, field) \ |
| 813 | for ((var) = ((head)->cqh_first); \ |
| 814 | (var) != CIRCLEQ_ENDC(head); \ |
| 815 | (var) = ((var)->field.cqe_next)) |
| 816 | |
| 817 | #define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ |
| 818 | for ((var) = ((head)->cqh_last); \ |
| 819 | (var) != CIRCLEQ_ENDC(head); \ |
| 820 | (var) = ((var)->field.cqe_prev)) |
| 821 | |
| 822 | /* |
| 823 | * Circular queue access methods. |
| 824 | */ |
| 825 | #define CIRCLEQ_FIRST(head) ((head)->cqh_first) |
| 826 | #define CIRCLEQ_LAST(head) ((head)->cqh_last) |
| 827 | /* For comparisons */ |
| 828 | #define CIRCLEQ_ENDC(head) (__launder_type(head)) |
| 829 | /* For assignments */ |
| 830 | #define CIRCLEQ_END(head) ((void *)(head)) |
| 831 | #define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) |
| 832 | #define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) |
| 833 | #define CIRCLEQ_EMPTY(head) \ |
| 834 | (CIRCLEQ_FIRST(head) == CIRCLEQ_ENDC(head)) |
| 835 | |
| 836 | #define CIRCLEQ_LOOP_NEXT(head, elm, field) \ |
| 837 | (((elm)->field.cqe_next == CIRCLEQ_ENDC(head)) \ |
| 838 | ? ((head)->cqh_first) \ |
| 839 | : (elm->field.cqe_next)) |
| 840 | #define CIRCLEQ_LOOP_PREV(head, elm, field) \ |
| 841 | (((elm)->field.cqe_prev == CIRCLEQ_ENDC(head)) \ |
| 842 | ? ((head)->cqh_last) \ |
| 843 | : (elm->field.cqe_prev)) |
| 844 | #endif /* !_KERNEL */ |
| 845 | |
| 846 | #endif /* !_SYS_QUEUE_H_ */ |