1290001Sglebius/* $OpenBSD: queue.h,v 1.16 2000/09/07 19:47:59 art Exp $ */ 2290001Sglebius/* $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $ */ 3290001Sglebius 4290001Sglebius/* 5290001Sglebius * Copyright (c) 1991, 1993 6290001Sglebius * The Regents of the University of California. All rights reserved. 7290001Sglebius * 8290001Sglebius * Redistribution and use in source and binary forms, with or without 9290001Sglebius * modification, are permitted provided that the following conditions 10290001Sglebius * are met: 11290001Sglebius * 1. Redistributions of source code must retain the above copyright 12290001Sglebius * notice, this list of conditions and the following disclaimer. 13290001Sglebius * 2. Redistributions in binary form must reproduce the above copyright 14290001Sglebius * notice, this list of conditions and the following disclaimer in the 15290001Sglebius * documentation and/or other materials provided with the distribution. 16290001Sglebius * 3. Neither the name of the University nor the names of its contributors 17290001Sglebius * may be used to endorse or promote products derived from this software 18290001Sglebius * without specific prior written permission. 19290001Sglebius * 20290001Sglebius * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21290001Sglebius * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22290001Sglebius * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23290001Sglebius * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24290001Sglebius * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25290001Sglebius * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26290001Sglebius * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27290001Sglebius * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28290001Sglebius * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29290001Sglebius * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30290001Sglebius * SUCH DAMAGE. 31290001Sglebius * 32290001Sglebius * @(#)queue.h 8.5 (Berkeley) 8/20/94 33290001Sglebius */ 34290001Sglebius 35290001Sglebius#ifndef SYS_QUEUE_H__ 36290001Sglebius#define SYS_QUEUE_H__ 37290001Sglebius 38290001Sglebius/* 39290001Sglebius * This file defines five types of data structures: singly-linked lists, 40290001Sglebius * lists, simple queues, tail queues, and circular queues. 41290001Sglebius * 42290001Sglebius * 43290001Sglebius * A singly-linked list is headed by a single forward pointer. The elements 44290001Sglebius * are singly linked for minimum space and pointer manipulation overhead at 45290001Sglebius * the expense of O(n) removal for arbitrary elements. New elements can be 46290001Sglebius * added to the list after an existing element or at the head of the list. 47290001Sglebius * Elements being removed from the head of the list should use the explicit 48290001Sglebius * macro for this purpose for optimum efficiency. A singly-linked list may 49290001Sglebius * only be traversed in the forward direction. Singly-linked lists are ideal 50290001Sglebius * for applications with large datasets and few or no removals or for 51290001Sglebius * implementing a LIFO queue. 52290001Sglebius * 53290001Sglebius * A list is headed by a single forward pointer (or an array of forward 54290001Sglebius * pointers for a hash table header). The elements are doubly linked 55290001Sglebius * so that an arbitrary element can be removed without a need to 56290001Sglebius * traverse the list. New elements can be added to the list before 57290001Sglebius * or after an existing element or at the head of the list. A list 58290001Sglebius * may only be traversed in the forward direction. 59290001Sglebius * 60290001Sglebius * A simple queue is headed by a pair of pointers, one the head of the 61290001Sglebius * list and the other to the tail of the list. The elements are singly 62290001Sglebius * linked to save space, so elements can only be removed from the 63290001Sglebius * head of the list. New elements can be added to the list before or after 64290001Sglebius * an existing element, at the head of the list, or at the end of the 65290001Sglebius * list. A simple queue may only be traversed in the forward direction. 66290001Sglebius * 67290001Sglebius * A tail queue is headed by a pair of pointers, one to the head of the 68290001Sglebius * list and the other to the tail of the list. The elements are doubly 69290001Sglebius * linked so that an arbitrary element can be removed without a need to 70290001Sglebius * traverse the list. New elements can be added to the list before or 71290001Sglebius * after an existing element, at the head of the list, or at the end of 72290001Sglebius * the list. A tail queue may be traversed in either direction. 73290001Sglebius * 74290001Sglebius * A circle queue is headed by a pair of pointers, one to the head of the 75290001Sglebius * list and the other to the tail of the list. The elements are doubly 76290001Sglebius * linked so that an arbitrary element can be removed without a need to 77290001Sglebius * traverse the list. New elements can be added to the list before or after 78290001Sglebius * an existing element, at the head of the list, or at the end of the list. 79290001Sglebius * A circle queue may be traversed in either direction, but has a more 80290001Sglebius * complex end of list detection. 81290001Sglebius * 82290001Sglebius * For details on the use of these macros, see the queue(3) manual page. 83290001Sglebius */ 84290001Sglebius 85290001Sglebius/* 86290001Sglebius * Singly-linked List definitions. 87290001Sglebius */ 88290001Sglebius#define SLIST_HEAD(name, type) \ 89290001Sglebiusstruct name { \ 90290001Sglebius struct type *slh_first; /* first element */ \ 91290001Sglebius} 92290001Sglebius 93290001Sglebius#define SLIST_HEAD_INITIALIZER(head) \ 94290001Sglebius { NULL } 95290001Sglebius 96290001Sglebius#ifndef _WIN32 97290001Sglebius#define SLIST_ENTRY(type) \ 98290001Sglebiusstruct { \ 99290001Sglebius struct type *sle_next; /* next element */ \ 100290001Sglebius} 101290001Sglebius#endif 102290001Sglebius 103290001Sglebius/* 104290001Sglebius * Singly-linked List access methods. 105290001Sglebius */ 106290001Sglebius#define SLIST_FIRST(head) ((head)->slh_first) 107290001Sglebius#define SLIST_END(head) NULL 108290001Sglebius#define SLIST_EMPTY(head) (SLIST_FIRST(head) == SLIST_END(head)) 109290001Sglebius#define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 110290001Sglebius 111290001Sglebius#define SLIST_FOREACH(var, head, field) \ 112290001Sglebius for((var) = SLIST_FIRST(head); \ 113290001Sglebius (var) != SLIST_END(head); \ 114290001Sglebius (var) = SLIST_NEXT(var, field)) 115290001Sglebius 116290001Sglebius/* 117290001Sglebius * Singly-linked List functions. 118290001Sglebius */ 119290001Sglebius#define SLIST_INIT(head) { \ 120290001Sglebius SLIST_FIRST(head) = SLIST_END(head); \ 121290001Sglebius} 122290001Sglebius 123290001Sglebius#define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 124290001Sglebius (elm)->field.sle_next = (slistelm)->field.sle_next; \ 125290001Sglebius (slistelm)->field.sle_next = (elm); \ 126290001Sglebius} while (0) 127290001Sglebius 128290001Sglebius#define SLIST_INSERT_HEAD(head, elm, field) do { \ 129290001Sglebius (elm)->field.sle_next = (head)->slh_first; \ 130290001Sglebius (head)->slh_first = (elm); \ 131290001Sglebius} while (0) 132290001Sglebius 133290001Sglebius#define SLIST_REMOVE_HEAD(head, field) do { \ 134290001Sglebius (head)->slh_first = (head)->slh_first->field.sle_next; \ 135290001Sglebius} while (0) 136290001Sglebius 137290001Sglebius/* 138290001Sglebius * List definitions. 139290001Sglebius */ 140290001Sglebius#define LIST_HEAD(name, type) \ 141290001Sglebiusstruct name { \ 142290001Sglebius struct type *lh_first; /* first element */ \ 143290001Sglebius} 144290001Sglebius 145290001Sglebius#define LIST_HEAD_INITIALIZER(head) \ 146290001Sglebius { NULL } 147290001Sglebius 148290001Sglebius#define LIST_ENTRY(type) \ 149290001Sglebiusstruct { \ 150290001Sglebius struct type *le_next; /* next element */ \ 151290001Sglebius struct type **le_prev; /* address of previous next element */ \ 152290001Sglebius} 153290001Sglebius 154290001Sglebius/* 155290001Sglebius * List access methods 156290001Sglebius */ 157290001Sglebius#define LIST_FIRST(head) ((head)->lh_first) 158290001Sglebius#define LIST_END(head) NULL 159290001Sglebius#define LIST_EMPTY(head) (LIST_FIRST(head) == LIST_END(head)) 160290001Sglebius#define LIST_NEXT(elm, field) ((elm)->field.le_next) 161290001Sglebius 162290001Sglebius#define LIST_FOREACH(var, head, field) \ 163290001Sglebius for((var) = LIST_FIRST(head); \ 164290001Sglebius (var)!= LIST_END(head); \ 165290001Sglebius (var) = LIST_NEXT(var, field)) 166290001Sglebius 167290001Sglebius/* 168290001Sglebius * List functions. 169290001Sglebius */ 170290001Sglebius#define LIST_INIT(head) do { \ 171290001Sglebius LIST_FIRST(head) = LIST_END(head); \ 172290001Sglebius} while (0) 173290001Sglebius 174290001Sglebius#define LIST_INSERT_AFTER(listelm, elm, field) do { \ 175290001Sglebius if (((elm)->field.le_next = (listelm)->field.le_next) != NULL) \ 176290001Sglebius (listelm)->field.le_next->field.le_prev = \ 177290001Sglebius &(elm)->field.le_next; \ 178290001Sglebius (listelm)->field.le_next = (elm); \ 179290001Sglebius (elm)->field.le_prev = &(listelm)->field.le_next; \ 180290001Sglebius} while (0) 181290001Sglebius 182290001Sglebius#define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 183290001Sglebius (elm)->field.le_prev = (listelm)->field.le_prev; \ 184290001Sglebius (elm)->field.le_next = (listelm); \ 185290001Sglebius *(listelm)->field.le_prev = (elm); \ 186290001Sglebius (listelm)->field.le_prev = &(elm)->field.le_next; \ 187290001Sglebius} while (0) 188290001Sglebius 189290001Sglebius#define LIST_INSERT_HEAD(head, elm, field) do { \ 190290001Sglebius if (((elm)->field.le_next = (head)->lh_first) != NULL) \ 191290001Sglebius (head)->lh_first->field.le_prev = &(elm)->field.le_next;\ 192290001Sglebius (head)->lh_first = (elm); \ 193290001Sglebius (elm)->field.le_prev = &(head)->lh_first; \ 194290001Sglebius} while (0) 195290001Sglebius 196290001Sglebius#define LIST_REMOVE(elm, field) do { \ 197290001Sglebius if ((elm)->field.le_next != NULL) \ 198290001Sglebius (elm)->field.le_next->field.le_prev = \ 199290001Sglebius (elm)->field.le_prev; \ 200290001Sglebius *(elm)->field.le_prev = (elm)->field.le_next; \ 201290001Sglebius} while (0) 202290001Sglebius 203290001Sglebius#define LIST_REPLACE(elm, elm2, field) do { \ 204290001Sglebius if (((elm2)->field.le_next = (elm)->field.le_next) != NULL) \ 205290001Sglebius (elm2)->field.le_next->field.le_prev = \ 206290001Sglebius &(elm2)->field.le_next; \ 207290001Sglebius (elm2)->field.le_prev = (elm)->field.le_prev; \ 208290001Sglebius *(elm2)->field.le_prev = (elm2); \ 209290001Sglebius} while (0) 210290001Sglebius 211290001Sglebius/* 212290001Sglebius * Simple queue definitions. 213290001Sglebius */ 214290001Sglebius#define SIMPLEQ_HEAD(name, type) \ 215290001Sglebiusstruct name { \ 216290001Sglebius struct type *sqh_first; /* first element */ \ 217290001Sglebius struct type **sqh_last; /* addr of last next element */ \ 218290001Sglebius} 219290001Sglebius 220290001Sglebius#define SIMPLEQ_HEAD_INITIALIZER(head) \ 221290001Sglebius { NULL, &(head).sqh_first } 222290001Sglebius 223290001Sglebius#define SIMPLEQ_ENTRY(type) \ 224290001Sglebiusstruct { \ 225290001Sglebius struct type *sqe_next; /* next element */ \ 226290001Sglebius} 227290001Sglebius 228290001Sglebius/* 229290001Sglebius * Simple queue access methods. 230290001Sglebius */ 231290001Sglebius#define SIMPLEQ_FIRST(head) ((head)->sqh_first) 232290001Sglebius#define SIMPLEQ_END(head) NULL 233290001Sglebius#define SIMPLEQ_EMPTY(head) (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head)) 234290001Sglebius#define SIMPLEQ_NEXT(elm, field) ((elm)->field.sqe_next) 235290001Sglebius 236290001Sglebius#define SIMPLEQ_FOREACH(var, head, field) \ 237290001Sglebius for((var) = SIMPLEQ_FIRST(head); \ 238290001Sglebius (var) != SIMPLEQ_END(head); \ 239290001Sglebius (var) = SIMPLEQ_NEXT(var, field)) 240290001Sglebius 241290001Sglebius/* 242290001Sglebius * Simple queue functions. 243290001Sglebius */ 244290001Sglebius#define SIMPLEQ_INIT(head) do { \ 245290001Sglebius (head)->sqh_first = NULL; \ 246290001Sglebius (head)->sqh_last = &(head)->sqh_first; \ 247290001Sglebius} while (0) 248290001Sglebius 249290001Sglebius#define SIMPLEQ_INSERT_HEAD(head, elm, field) do { \ 250290001Sglebius if (((elm)->field.sqe_next = (head)->sqh_first) == NULL) \ 251290001Sglebius (head)->sqh_last = &(elm)->field.sqe_next; \ 252290001Sglebius (head)->sqh_first = (elm); \ 253290001Sglebius} while (0) 254290001Sglebius 255290001Sglebius#define SIMPLEQ_INSERT_TAIL(head, elm, field) do { \ 256290001Sglebius (elm)->field.sqe_next = NULL; \ 257290001Sglebius *(head)->sqh_last = (elm); \ 258290001Sglebius (head)->sqh_last = &(elm)->field.sqe_next; \ 259290001Sglebius} while (0) 260290001Sglebius 261290001Sglebius#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 262290001Sglebius if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\ 263290001Sglebius (head)->sqh_last = &(elm)->field.sqe_next; \ 264290001Sglebius (listelm)->field.sqe_next = (elm); \ 265290001Sglebius} while (0) 266290001Sglebius 267290001Sglebius#define SIMPLEQ_REMOVE_HEAD(head, elm, field) do { \ 268290001Sglebius if (((head)->sqh_first = (elm)->field.sqe_next) == NULL) \ 269290001Sglebius (head)->sqh_last = &(head)->sqh_first; \ 270290001Sglebius} while (0) 271290001Sglebius 272290001Sglebius/* 273290001Sglebius * Tail queue definitions. 274290001Sglebius */ 275290001Sglebius#define TAILQ_HEAD(name, type) \ 276290001Sglebiusstruct name { \ 277290001Sglebius struct type *tqh_first; /* first element */ \ 278290001Sglebius struct type **tqh_last; /* addr of last next element */ \ 279290001Sglebius} 280290001Sglebius 281290001Sglebius#define TAILQ_HEAD_INITIALIZER(head) \ 282290001Sglebius { NULL, &(head).tqh_first } 283290001Sglebius 284290001Sglebius#define TAILQ_ENTRY(type) \ 285290001Sglebiusstruct { \ 286290001Sglebius struct type *tqe_next; /* next element */ \ 287290001Sglebius struct type **tqe_prev; /* address of previous next element */ \ 288290001Sglebius} 289290001Sglebius 290290001Sglebius/* 291290001Sglebius * tail queue access methods 292290001Sglebius */ 293290001Sglebius#define TAILQ_FIRST(head) ((head)->tqh_first) 294290001Sglebius#define TAILQ_END(head) NULL 295290001Sglebius#define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 296290001Sglebius#define TAILQ_LAST(head, headname) \ 297290001Sglebius (*(((struct headname *)((head)->tqh_last))->tqh_last)) 298290001Sglebius/* XXX */ 299290001Sglebius#define TAILQ_PREV(elm, headname, field) \ 300290001Sglebius (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 301290001Sglebius#define TAILQ_EMPTY(head) \ 302290001Sglebius (TAILQ_FIRST(head) == TAILQ_END(head)) 303290001Sglebius 304290001Sglebius#define TAILQ_FOREACH(var, head, field) \ 305290001Sglebius for((var) = TAILQ_FIRST(head); \ 306290001Sglebius (var) != TAILQ_END(head); \ 307290001Sglebius (var) = TAILQ_NEXT(var, field)) 308290001Sglebius 309290001Sglebius#define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 310290001Sglebius for((var) = TAILQ_LAST(head, headname); \ 311290001Sglebius (var) != TAILQ_END(head); \ 312290001Sglebius (var) = TAILQ_PREV(var, headname, field)) 313290001Sglebius 314290001Sglebius/* 315290001Sglebius * Tail queue functions. 316290001Sglebius */ 317290001Sglebius#define TAILQ_INIT(head) do { \ 318290001Sglebius (head)->tqh_first = NULL; \ 319290001Sglebius (head)->tqh_last = &(head)->tqh_first; \ 320290001Sglebius} while (0) 321290001Sglebius 322290001Sglebius#define TAILQ_INSERT_HEAD(head, elm, field) do { \ 323290001Sglebius if (((elm)->field.tqe_next = (head)->tqh_first) != NULL) \ 324290001Sglebius (head)->tqh_first->field.tqe_prev = \ 325290001Sglebius &(elm)->field.tqe_next; \ 326290001Sglebius else \ 327290001Sglebius (head)->tqh_last = &(elm)->field.tqe_next; \ 328290001Sglebius (head)->tqh_first = (elm); \ 329290001Sglebius (elm)->field.tqe_prev = &(head)->tqh_first; \ 330290001Sglebius} while (0) 331290001Sglebius 332290001Sglebius#define TAILQ_INSERT_TAIL(head, elm, field) do { \ 333290001Sglebius (elm)->field.tqe_next = NULL; \ 334290001Sglebius (elm)->field.tqe_prev = (head)->tqh_last; \ 335290001Sglebius *(head)->tqh_last = (elm); \ 336290001Sglebius (head)->tqh_last = &(elm)->field.tqe_next; \ 337290001Sglebius} while (0) 338290001Sglebius 339290001Sglebius#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 340290001Sglebius if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\ 341290001Sglebius (elm)->field.tqe_next->field.tqe_prev = \ 342290001Sglebius &(elm)->field.tqe_next; \ 343290001Sglebius else \ 344290001Sglebius (head)->tqh_last = &(elm)->field.tqe_next; \ 345290001Sglebius (listelm)->field.tqe_next = (elm); \ 346290001Sglebius (elm)->field.tqe_prev = &(listelm)->field.tqe_next; \ 347290001Sglebius} while (0) 348290001Sglebius 349290001Sglebius#define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 350290001Sglebius (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 351290001Sglebius (elm)->field.tqe_next = (listelm); \ 352290001Sglebius *(listelm)->field.tqe_prev = (elm); \ 353290001Sglebius (listelm)->field.tqe_prev = &(elm)->field.tqe_next; \ 354290001Sglebius} while (0) 355290001Sglebius 356290001Sglebius#define TAILQ_REMOVE(head, elm, field) do { \ 357290001Sglebius if (((elm)->field.tqe_next) != NULL) \ 358290001Sglebius (elm)->field.tqe_next->field.tqe_prev = \ 359290001Sglebius (elm)->field.tqe_prev; \ 360290001Sglebius else \ 361290001Sglebius (head)->tqh_last = (elm)->field.tqe_prev; \ 362290001Sglebius *(elm)->field.tqe_prev = (elm)->field.tqe_next; \ 363290001Sglebius} while (0) 364290001Sglebius 365290001Sglebius#define TAILQ_REPLACE(head, elm, elm2, field) do { \ 366290001Sglebius if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL) \ 367290001Sglebius (elm2)->field.tqe_next->field.tqe_prev = \ 368290001Sglebius &(elm2)->field.tqe_next; \ 369290001Sglebius else \ 370290001Sglebius (head)->tqh_last = &(elm2)->field.tqe_next; \ 371290001Sglebius (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 372290001Sglebius *(elm2)->field.tqe_prev = (elm2); \ 373290001Sglebius} while (0) 374290001Sglebius 375290001Sglebius/* 376290001Sglebius * Circular queue definitions. 377290001Sglebius */ 378290001Sglebius#define CIRCLEQ_HEAD(name, type) \ 379290001Sglebiusstruct name { \ 380290001Sglebius struct type *cqh_first; /* first element */ \ 381290001Sglebius struct type *cqh_last; /* last element */ \ 382290001Sglebius} 383290001Sglebius 384290001Sglebius#define CIRCLEQ_HEAD_INITIALIZER(head) \ 385290001Sglebius { CIRCLEQ_END(&head), CIRCLEQ_END(&head) } 386290001Sglebius 387290001Sglebius#define CIRCLEQ_ENTRY(type) \ 388290001Sglebiusstruct { \ 389290001Sglebius struct type *cqe_next; /* next element */ \ 390290001Sglebius struct type *cqe_prev; /* previous element */ \ 391290001Sglebius} 392290001Sglebius 393290001Sglebius/* 394290001Sglebius * Circular queue access methods 395290001Sglebius */ 396290001Sglebius#define CIRCLEQ_FIRST(head) ((head)->cqh_first) 397290001Sglebius#define CIRCLEQ_LAST(head) ((head)->cqh_last) 398290001Sglebius#define CIRCLEQ_END(head) ((void *)(head)) 399290001Sglebius#define CIRCLEQ_NEXT(elm, field) ((elm)->field.cqe_next) 400290001Sglebius#define CIRCLEQ_PREV(elm, field) ((elm)->field.cqe_prev) 401290001Sglebius#define CIRCLEQ_EMPTY(head) \ 402290001Sglebius (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head)) 403290001Sglebius 404290001Sglebius#define CIRCLEQ_FOREACH(var, head, field) \ 405290001Sglebius for((var) = CIRCLEQ_FIRST(head); \ 406290001Sglebius (var) != CIRCLEQ_END(head); \ 407290001Sglebius (var) = CIRCLEQ_NEXT(var, field)) 408290001Sglebius 409290001Sglebius#define CIRCLEQ_FOREACH_REVERSE(var, head, field) \ 410290001Sglebius for((var) = CIRCLEQ_LAST(head); \ 411290001Sglebius (var) != CIRCLEQ_END(head); \ 412290001Sglebius (var) = CIRCLEQ_PREV(var, field)) 413290001Sglebius 414290001Sglebius/* 415290001Sglebius * Circular queue functions. 416290001Sglebius */ 417290001Sglebius#define CIRCLEQ_INIT(head) do { \ 418290001Sglebius (head)->cqh_first = CIRCLEQ_END(head); \ 419290001Sglebius (head)->cqh_last = CIRCLEQ_END(head); \ 420290001Sglebius} while (0) 421290001Sglebius 422290001Sglebius#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do { \ 423290001Sglebius (elm)->field.cqe_next = (listelm)->field.cqe_next; \ 424290001Sglebius (elm)->field.cqe_prev = (listelm); \ 425290001Sglebius if ((listelm)->field.cqe_next == CIRCLEQ_END(head)) \ 426290001Sglebius (head)->cqh_last = (elm); \ 427290001Sglebius else \ 428290001Sglebius (listelm)->field.cqe_next->field.cqe_prev = (elm); \ 429290001Sglebius (listelm)->field.cqe_next = (elm); \ 430290001Sglebius} while (0) 431290001Sglebius 432290001Sglebius#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do { \ 433290001Sglebius (elm)->field.cqe_next = (listelm); \ 434290001Sglebius (elm)->field.cqe_prev = (listelm)->field.cqe_prev; \ 435290001Sglebius if ((listelm)->field.cqe_prev == CIRCLEQ_END(head)) \ 436290001Sglebius (head)->cqh_first = (elm); \ 437290001Sglebius else \ 438290001Sglebius (listelm)->field.cqe_prev->field.cqe_next = (elm); \ 439290001Sglebius (listelm)->field.cqe_prev = (elm); \ 440290001Sglebius} while (0) 441290001Sglebius 442290001Sglebius#define CIRCLEQ_INSERT_HEAD(head, elm, field) do { \ 443290001Sglebius (elm)->field.cqe_next = (head)->cqh_first; \ 444290001Sglebius (elm)->field.cqe_prev = CIRCLEQ_END(head); \ 445290001Sglebius if ((head)->cqh_last == CIRCLEQ_END(head)) \ 446290001Sglebius (head)->cqh_last = (elm); \ 447290001Sglebius else \ 448290001Sglebius (head)->cqh_first->field.cqe_prev = (elm); \ 449290001Sglebius (head)->cqh_first = (elm); \ 450290001Sglebius} while (0) 451290001Sglebius 452290001Sglebius#define CIRCLEQ_INSERT_TAIL(head, elm, field) do { \ 453290001Sglebius (elm)->field.cqe_next = CIRCLEQ_END(head); \ 454290001Sglebius (elm)->field.cqe_prev = (head)->cqh_last; \ 455290001Sglebius if ((head)->cqh_first == CIRCLEQ_END(head)) \ 456290001Sglebius (head)->cqh_first = (elm); \ 457290001Sglebius else \ 458290001Sglebius (head)->cqh_last->field.cqe_next = (elm); \ 459290001Sglebius (head)->cqh_last = (elm); \ 460290001Sglebius} while (0) 461290001Sglebius 462290001Sglebius#define CIRCLEQ_REMOVE(head, elm, field) do { \ 463290001Sglebius if ((elm)->field.cqe_next == CIRCLEQ_END(head)) \ 464290001Sglebius (head)->cqh_last = (elm)->field.cqe_prev; \ 465290001Sglebius else \ 466290001Sglebius (elm)->field.cqe_next->field.cqe_prev = \ 467290001Sglebius (elm)->field.cqe_prev; \ 468290001Sglebius if ((elm)->field.cqe_prev == CIRCLEQ_END(head)) \ 469290001Sglebius (head)->cqh_first = (elm)->field.cqe_next; \ 470290001Sglebius else \ 471290001Sglebius (elm)->field.cqe_prev->field.cqe_next = \ 472290001Sglebius (elm)->field.cqe_next; \ 473290001Sglebius} while (0) 474290001Sglebius 475290001Sglebius#define CIRCLEQ_REPLACE(head, elm, elm2, field) do { \ 476290001Sglebius if (((elm2)->field.cqe_next = (elm)->field.cqe_next) == \ 477290001Sglebius CIRCLEQ_END(head)) \ 478290001Sglebius (head).cqh_last = (elm2); \ 479290001Sglebius else \ 480290001Sglebius (elm2)->field.cqe_next->field.cqe_prev = (elm2); \ 481290001Sglebius if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) == \ 482290001Sglebius CIRCLEQ_END(head)) \ 483290001Sglebius (head).cqh_first = (elm2); \ 484290001Sglebius else \ 485290001Sglebius (elm2)->field.cqe_prev->field.cqe_next = (elm2); \ 486290001Sglebius} while (0) 487290001Sglebius 488290001Sglebius#endif /* !SYS_QUEUE_H__ */ 489