crypto/openssh-3.8.1p1/openbsd-compat/sys-queue.h

   1 /* OPENBSD ORIGINAL: sys/sys/queue.h */
   2
   3 /*      $OpenBSD: queue.h,v 1.23 2003/06/02 23:28:21 millert Exp $      */
   4 /*      $NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $       */
   5
   6 /*
   7  * Copyright (c) 1991, 1993
   8  *      The Regents of the University of California.  All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)queue.h     8.5 (Berkeley) 8/20/94
  35  */
  36
  37 #ifndef _FAKE_QUEUE_H_
  38 #define _FAKE_QUEUE_H_
  39
  40 /*
  41  * Ignore all <sys/queue.h> since older platforms have broken/incomplete
  42  * <sys/queue.h> that are too hard to work around.
  43  */
  44 #undef SLIST_HEAD
  45 #undef SLIST_HEAD_INITIALIZER
  46 #undef SLIST_ENTRY
  47 #undef SLIST_FIRST
  48 #undef SLIST_END
  49 #undef SLIST_EMPTY
  50 #undef SLIST_NEXT
  51 #undef SLIST_FOREACH
  52 #undef SLIST_INIT
  53 #undef SLIST_INSERT_AFTER
  54 #undef SLIST_INSERT_HEAD
  55 #undef SLIST_REMOVE_HEAD
  56 #undef SLIST_REMOVE
  57 #undef LIST_HEAD
  58 #undef LIST_HEAD_INITIALIZER
  59 #undef LIST_ENTRY
  60 #undef LIST_FIRST
  61 #undef LIST_END
  62 #undef LIST_EMPTY
  63 #undef LIST_NEXT
  64 #undef LIST_FOREACH
  65 #undef LIST_INIT
  66 #undef LIST_INSERT_AFTER
  67 #undef LIST_INSERT_BEFORE
  68 #undef LIST_INSERT_HEAD
  69 #undef LIST_REMOVE
  70 #undef LIST_REPLACE
  71 #undef SIMPLEQ_HEAD
  72 #undef SIMPLEQ_HEAD_INITIALIZER
  73 #undef SIMPLEQ_ENTRY
  74 #undef SIMPLEQ_FIRST
  75 #undef SIMPLEQ_END
  76 #undef SIMPLEQ_EMPTY
  77 #undef SIMPLEQ_NEXT
  78 #undef SIMPLEQ_FOREACH
  79 #undef SIMPLEQ_INIT
  80 #undef SIMPLEQ_INSERT_HEAD
  81 #undef SIMPLEQ_INSERT_TAIL
  82 #undef SIMPLEQ_INSERT_AFTER
  83 #undef SIMPLEQ_REMOVE_HEAD
  84 #undef TAILQ_HEAD
  85 #undef TAILQ_HEAD_INITIALIZER
  86 #undef TAILQ_ENTRY
  87 #undef TAILQ_FIRST
  88 #undef TAILQ_END
  89 #undef TAILQ_NEXT
  90 #undef TAILQ_LAST
  91 #undef TAILQ_PREV
  92 #undef TAILQ_EMPTY
  93 #undef TAILQ_FOREACH
  94 #undef TAILQ_FOREACH_REVERSE
  95 #undef TAILQ_INIT
  96 #undef TAILQ_INSERT_HEAD
  97 #undef TAILQ_INSERT_TAIL
  98 #undef TAILQ_INSERT_AFTER
  99 #undef TAILQ_INSERT_BEFORE
 100 #undef TAILQ_REMOVE
 101 #undef TAILQ_REPLACE
 102 #undef CIRCLEQ_HEAD
 103 #undef CIRCLEQ_HEAD_INITIALIZER
 104 #undef CIRCLEQ_ENTRY
 105 #undef CIRCLEQ_FIRST
 106 #undef CIRCLEQ_LAST
 107 #undef CIRCLEQ_END
 108 #undef CIRCLEQ_NEXT
 109 #undef CIRCLEQ_PREV
 110 #undef CIRCLEQ_EMPTY
 111 #undef CIRCLEQ_FOREACH
 112 #undef CIRCLEQ_FOREACH_REVERSE
 113 #undef CIRCLEQ_INIT
 114 #undef CIRCLEQ_INSERT_AFTER
 115 #undef CIRCLEQ_INSERT_BEFORE
 116 #undef CIRCLEQ_INSERT_HEAD
 117 #undef CIRCLEQ_INSERT_TAIL
 118 #undef CIRCLEQ_REMOVE
 119 #undef CIRCLEQ_REPLACE
 120
 121 /*
 122  * This file defines five types of data structures: singly-linked lists,
 123  * lists, simple queues, tail queues, and circular queues.
 124  *
 125  *
 126  * A singly-linked list is headed by a single forward pointer. The elements
 127  * are singly linked for minimum space and pointer manipulation overhead at
 128  * the expense of O(n) removal for arbitrary elements. New elements can be
 129  * added to the list after an existing element or at the head of the list.
 130  * Elements being removed from the head of the list should use the explicit
 131  * macro for this purpose for optimum efficiency. A singly-linked list may
 132  * only be traversed in the forward direction.  Singly-linked lists are ideal
 133  * for applications with large datasets and few or no removals or for
 134  * implementing a LIFO queue.
 135  *
 136  * A list is headed by a single forward pointer (or an array of forward
 137  * pointers for a hash table header). The elements are doubly linked
 138  * so that an arbitrary element can be removed without a need to
 139  * traverse the list. New elements can be added to the list before
 140  * or after an existing element or at the head of the list. A list
 141  * may only be traversed in the forward direction.
 142  *
 143  * A simple queue is headed by a pair of pointers, one the head of the
 144  * list and the other to the tail of the list. The elements are singly
 145  * linked to save space, so elements can only be removed from the
 146  * head of the list. New elements can be added to the list before or after
 147  * an existing element, at the head of the list, or at the end of the
 148  * list. A simple queue may only be traversed in the forward direction.
 149  *
 150  * A tail queue is headed by a pair of pointers, one to the head of the
 151  * list and the other to the tail of the list. The elements are doubly
 152  * linked so that an arbitrary element can be removed without a need to
 153  * traverse the list. New elements can be added to the list before or
 154  * after an existing element, at the head of the list, or at the end of
 155  * the list. A tail queue may be traversed in either direction.
 156  *
 157  * A circle 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 after
 161  * an existing element, at the head of the list, or at the end of the list.
 162  * A circle queue may be traversed in either direction, but has a more
 163  * complex end of list detection.
 164  *
 165  * For details on the use of these macros, see the queue(3) manual page.
 166  */
 167
 168 /*
 169  * Singly-linked List definitions.
 170  */
 171 #define SLIST_HEAD(name, type)                                          \
 172 struct name {                                                           \
 173         struct type *slh_first; /* first element */                     \
 174 }
 175
 176 #define SLIST_HEAD_INITIALIZER(head)                                    \
 177         { NULL }
 178
 179 #define SLIST_ENTRY(type)                                               \
 180 struct {                                                                \
 181         struct type *sle_next;  /* next element */                      \
 182 }
 183
 184 /*
 185  * Singly-linked List access methods.
 186  */
 187 #define SLIST_FIRST(head)       ((head)->slh_first)
 188 #define SLIST_END(head)         NULL
 189 #define SLIST_EMPTY(head)       (SLIST_FIRST(head) == SLIST_END(head))
 190 #define SLIST_NEXT(elm, field)  ((elm)->field.sle_next)
 191
 192 #define SLIST_FOREACH(var, head, field)                                 \
 193         for((var) = SLIST_FIRST(head);                                  \
 194             (var) != SLIST_END(head);                                   \
 195             (var) = SLIST_NEXT(var, field))
 196
 197 /*
 198  * Singly-linked List functions.
 199  */
 200 #define SLIST_INIT(head) {                                              \
 201         SLIST_FIRST(head) = SLIST_END(head);                            \
 202 }
 203
 204 #define SLIST_INSERT_AFTER(slistelm, elm, field) do {                   \
 205         (elm)->field.sle_next = (slistelm)->field.sle_next;             \
 206         (slistelm)->field.sle_next = (elm);                             \
 207 } while (0)
 208
 209 #define SLIST_INSERT_HEAD(head, elm, field) do {                        \
 210         (elm)->field.sle_next = (head)->slh_first;                      \
 211         (head)->slh_first = (elm);                                      \
 212 } while (0)
 213
 214 #define SLIST_REMOVE_HEAD(head, field) do {                             \
 215         (head)->slh_first = (head)->slh_first->field.sle_next;          \
 216 } while (0)
 217
 218 #define SLIST_REMOVE(head, elm, type, field) do {                       \
 219         if ((head)->slh_first == (elm)) {                               \
 220                 SLIST_REMOVE_HEAD((head), field);                       \
 221         }                                                               \
 222         else {                                                          \
 223                 struct type *curelm = (head)->slh_first;                \
 224                 while( curelm->field.sle_next != (elm) )                \
 225                         curelm = curelm->field.sle_next;                \
 226                 curelm->field.sle_next =                                \
 227                     curelm->field.sle_next->field.sle_next;             \
 228         }                                                               \
 229 } while (0)
 230
 231 /*
 232  * List definitions.
 233  */
 234 #define LIST_HEAD(name, type)                                           \
 235 struct name {                                                           \
 236         struct type *lh_first;  /* first element */                     \
 237 }
 238
 239 #define LIST_HEAD_INITIALIZER(head)                                     \
 240         { NULL }
 241
 242 #define LIST_ENTRY(type)                                                \
 243 struct {                                                                \
 244         struct type *le_next;   /* next element */                      \
 245         struct type **le_prev;  /* address of previous next element */  \
 246 }
 247
 248 /*
 249  * List access methods
 250  */
 251 #define LIST_FIRST(head)                ((head)->lh_first)
 252 #define LIST_END(head)                  NULL
 253 #define LIST_EMPTY(head)                (LIST_FIRST(head) == LIST_END(head))
 254 #define LIST_NEXT(elm, field)           ((elm)->field.le_next)
 255
 256 #define LIST_FOREACH(var, head, field)                                  \
 257         for((var) = LIST_FIRST(head);                                   \
 258             (var)!= LIST_END(head);                                     \
 259             (var) = LIST_NEXT(var, field))
 260
 261 /*
 262  * List functions.
 263  */
 264 #define LIST_INIT(head) do {                                            \
 265         LIST_FIRST(head) = LIST_END(head);                              \
 266 } while (0)
 267
 268 #define LIST_INSERT_AFTER(listelm, elm, field) do {                     \
 269         if (((elm)->field.le_next = (listelm)->field.le_next) != NULL)  \
 270                 (listelm)->field.le_next->field.le_prev =               \
 271                     &(elm)->field.le_next;                              \
 272         (listelm)->field.le_next = (elm);                               \
 273         (elm)->field.le_prev = &(listelm)->field.le_next;               \
 274 } while (0)
 275
 276 #define LIST_INSERT_BEFORE(listelm, elm, field) do {                    \
 277         (elm)->field.le_prev = (listelm)->field.le_prev;                \
 278         (elm)->field.le_next = (listelm);                               \
 279         *(listelm)->field.le_prev = (elm);                              \
 280         (listelm)->field.le_prev = &(elm)->field.le_next;               \
 281 } while (0)
 282
 283 #define LIST_INSERT_HEAD(head, elm, field) do {                         \
 284         if (((elm)->field.le_next = (head)->lh_first) != NULL)          \
 285                 (head)->lh_first->field.le_prev = &(elm)->field.le_next;\
 286         (head)->lh_first = (elm);                                       \
 287         (elm)->field.le_prev = &(head)->lh_first;                       \
 288 } while (0)
 289
 290 #define LIST_REMOVE(elm, field) do {                                    \
 291         if ((elm)->field.le_next != NULL)                               \
 292                 (elm)->field.le_next->field.le_prev =                   \
 293                     (elm)->field.le_prev;                               \
 294         *(elm)->field.le_prev = (elm)->field.le_next;                   \
 295 } while (0)
 296
 297 #define LIST_REPLACE(elm, elm2, field) do {                             \
 298         if (((elm2)->field.le_next = (elm)->field.le_next) != NULL)     \
 299                 (elm2)->field.le_next->field.le_prev =                  \
 300                     &(elm2)->field.le_next;                             \
 301         (elm2)->field.le_prev = (elm)->field.le_prev;                   \
 302         *(elm2)->field.le_prev = (elm2);                                \
 303 } while (0)
 304
 305 /*
 306  * Simple queue definitions.
 307  */
 308 #define SIMPLEQ_HEAD(name, type)                                        \
 309 struct name {                                                           \
 310         struct type *sqh_first; /* first element */                     \
 311         struct type **sqh_last; /* addr of last next element */         \
 312 }
 313
 314 #define SIMPLEQ_HEAD_INITIALIZER(head)                                  \
 315         { NULL, &(head).sqh_first }
 316
 317 #define SIMPLEQ_ENTRY(type)                                             \
 318 struct {                                                                \
 319         struct type *sqe_next;  /* next element */                      \
 320 }
 321
 322 /*
 323  * Simple queue access methods.
 324  */
 325 #define SIMPLEQ_FIRST(head)         ((head)->sqh_first)
 326 #define SIMPLEQ_END(head)           NULL
 327 #define SIMPLEQ_EMPTY(head)         (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
 328 #define SIMPLEQ_NEXT(elm, field)    ((elm)->field.sqe_next)
 329
 330 #define SIMPLEQ_FOREACH(var, head, field)                               \
 331         for((var) = SIMPLEQ_FIRST(head);                                \
 332             (var) != SIMPLEQ_END(head);                                 \
 333             (var) = SIMPLEQ_NEXT(var, field))
 334
 335 /*
 336  * Simple queue functions.
 337  */
 338 #define SIMPLEQ_INIT(head) do {                                         \
 339         (head)->sqh_first = NULL;                                       \
 340         (head)->sqh_last = &(head)->sqh_first;                          \
 341 } while (0)
 342
 343 #define SIMPLEQ_INSERT_HEAD(head, elm, field) do {                      \
 344         if (((elm)->field.sqe_next = (head)->sqh_first) == NULL)        \
 345                 (head)->sqh_last = &(elm)->field.sqe_next;              \
 346         (head)->sqh_first = (elm);                                      \
 347 } while (0)
 348
 349 #define SIMPLEQ_INSERT_TAIL(head, elm, field) do {                      \
 350         (elm)->field.sqe_next = NULL;                                   \
 351         *(head)->sqh_last = (elm);                                      \
 352         (head)->sqh_last = &(elm)->field.sqe_next;                      \
 353 } while (0)
 354
 355 #define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do {            \
 356         if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
 357                 (head)->sqh_last = &(elm)->field.sqe_next;              \
 358         (listelm)->field.sqe_next = (elm);                              \
 359 } while (0)
 360
 361 #define SIMPLEQ_REMOVE_HEAD(head, elm, field) do {                      \
 362         if (((head)->sqh_first = (elm)->field.sqe_next) == NULL)        \
 363                 (head)->sqh_last = &(head)->sqh_first;                  \
 364 } while (0)
 365
 366 /*
 367  * Tail queue definitions.
 368  */
 369 #define TAILQ_HEAD(name, type)                                          \
 370 struct name {                                                           \
 371         struct type *tqh_first; /* first element */                     \
 372         struct type **tqh_last; /* addr of last next element */         \
 373 }
 374
 375 #define TAILQ_HEAD_INITIALIZER(head)                                    \
 376         { NULL, &(head).tqh_first }
 377
 378 #define TAILQ_ENTRY(type)                                               \
 379 struct {                                                                \
 380         struct type *tqe_next;  /* next element */                      \
 381         struct type **tqe_prev; /* address of previous next element */  \
 382 }
 383
 384 /*
 385  * tail queue access methods
 386  */
 387 #define TAILQ_FIRST(head)               ((head)->tqh_first)
 388 #define TAILQ_END(head)                 NULL
 389 #define TAILQ_NEXT(elm, field)          ((elm)->field.tqe_next)
 390 #define TAILQ_LAST(head, headname)                                      \
 391         (*(((struct headname *)((head)->tqh_last))->tqh_last))
 392 /* XXX */
 393 #define TAILQ_PREV(elm, headname, field)                                \
 394         (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
 395 #define TAILQ_EMPTY(head)                                               \
 396         (TAILQ_FIRST(head) == TAILQ_END(head))
 397
 398 #define TAILQ_FOREACH(var, head, field)                                 \
 399         for((var) = TAILQ_FIRST(head);                                  \
 400             (var) != TAILQ_END(head);                                   \
 401             (var) = TAILQ_NEXT(var, field))
 402
 403 #define TAILQ_FOREACH_REVERSE(var, head, field, headname)               \
 404         for((var) = TAILQ_LAST(head, headname);                         \
 405             (var) != TAILQ_END(head);                                   \
 406             (var) = TAILQ_PREV(var, headname, field))
 407
 408 /*
 409  * Tail queue functions.
 410  */
 411 #define TAILQ_INIT(head) do {                                           \
 412         (head)->tqh_first = NULL;                                       \
 413         (head)->tqh_last = &(head)->tqh_first;                          \
 414 } while (0)
 415
 416 #define TAILQ_INSERT_HEAD(head, elm, field) do {                        \
 417         if (((elm)->field.tqe_next = (head)->tqh_first) != NULL)        \
 418                 (head)->tqh_first->field.tqe_prev =                     \
 419                     &(elm)->field.tqe_next;                             \
 420         else                                                            \
 421                 (head)->tqh_last = &(elm)->field.tqe_next;              \
 422         (head)->tqh_first = (elm);                                      \
 423         (elm)->field.tqe_prev = &(head)->tqh_first;                     \
 424 } while (0)
 425
 426 #define TAILQ_INSERT_TAIL(head, elm, field) do {                        \
 427         (elm)->field.tqe_next = NULL;                                   \
 428         (elm)->field.tqe_prev = (head)->tqh_last;                       \
 429         *(head)->tqh_last = (elm);                                      \
 430         (head)->tqh_last = &(elm)->field.tqe_next;                      \
 431 } while (0)
 432
 433 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do {              \
 434         if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
 435                 (elm)->field.tqe_next->field.tqe_prev =                 \
 436                     &(elm)->field.tqe_next;                             \
 437         else                                                            \
 438                 (head)->tqh_last = &(elm)->field.tqe_next;              \
 439         (listelm)->field.tqe_next = (elm);                              \
 440         (elm)->field.tqe_prev = &(listelm)->field.tqe_next;             \
 441 } while (0)
 442
 443 #define TAILQ_INSERT_BEFORE(listelm, elm, field) do {                   \
 444         (elm)->field.tqe_prev = (listelm)->field.tqe_prev;              \
 445         (elm)->field.tqe_next = (listelm);                              \
 446         *(listelm)->field.tqe_prev = (elm);                             \
 447         (listelm)->field.tqe_prev = &(elm)->field.tqe_next;             \
 448 } while (0)
 449
 450 #define TAILQ_REMOVE(head, elm, field) do {                             \
 451         if (((elm)->field.tqe_next) != NULL)                            \
 452                 (elm)->field.tqe_next->field.tqe_prev =                 \
 453                     (elm)->field.tqe_prev;                              \
 454         else                                                            \
 455                 (head)->tqh_last = (elm)->field.tqe_prev;               \
 456         *(elm)->field.tqe_prev = (elm)->field.tqe_next;                 \
 457 } while (0)
 458
 459 #define TAILQ_REPLACE(head, elm, elm2, field) do {                      \
 460         if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL)   \
 461                 (elm2)->field.tqe_next->field.tqe_prev =                \
 462                     &(elm2)->field.tqe_next;                            \
 463         else                                                            \
 464                 (head)->tqh_last = &(elm2)->field.tqe_next;             \
 465         (elm2)->field.tqe_prev = (elm)->field.tqe_prev;                 \
 466         *(elm2)->field.tqe_prev = (elm2);                               \
 467 } while (0)
 468
 469 /*
 470  * Circular queue definitions.
 471  */
 472 #define CIRCLEQ_HEAD(name, type)                                        \
 473 struct name {                                                           \
 474         struct type *cqh_first;         /* first element */             \
 475         struct type *cqh_last;          /* last element */              \
 476 }
 477
 478 #define CIRCLEQ_HEAD_INITIALIZER(head)                                  \
 479         { CIRCLEQ_END(&head), CIRCLEQ_END(&head) }
 480
 481 #define CIRCLEQ_ENTRY(type)                                             \
 482 struct {                                                                \
 483         struct type *cqe_next;          /* next element */              \
 484         struct type *cqe_prev;          /* previous element */          \
 485 }
 486
 487 /*
 488  * Circular queue access methods
 489  */
 490 #define CIRCLEQ_FIRST(head)             ((head)->cqh_first)
 491 #define CIRCLEQ_LAST(head)              ((head)->cqh_last)
 492 #define CIRCLEQ_END(head)               ((void *)(head))
 493 #define CIRCLEQ_NEXT(elm, field)        ((elm)->field.cqe_next)
 494 #define CIRCLEQ_PREV(elm, field)        ((elm)->field.cqe_prev)
 495 #define CIRCLEQ_EMPTY(head)                                             \
 496         (CIRCLEQ_FIRST(head) == CIRCLEQ_END(head))
 497
 498 #define CIRCLEQ_FOREACH(var, head, field)                               \
 499         for((var) = CIRCLEQ_FIRST(head);                                \
 500             (var) != CIRCLEQ_END(head);                                 \
 501             (var) = CIRCLEQ_NEXT(var, field))
 502
 503 #define CIRCLEQ_FOREACH_REVERSE(var, head, field)                       \
 504         for((var) = CIRCLEQ_LAST(head);                                 \
 505             (var) != CIRCLEQ_END(head);                                 \
 506             (var) = CIRCLEQ_PREV(var, field))
 507
 508 /*
 509  * Circular queue functions.
 510  */
 511 #define CIRCLEQ_INIT(head) do {                                         \
 512         (head)->cqh_first = CIRCLEQ_END(head);                          \
 513         (head)->cqh_last = CIRCLEQ_END(head);                           \
 514 } while (0)
 515
 516 #define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do {            \
 517         (elm)->field.cqe_next = (listelm)->field.cqe_next;              \
 518         (elm)->field.cqe_prev = (listelm);                              \
 519         if ((listelm)->field.cqe_next == CIRCLEQ_END(head))             \
 520                 (head)->cqh_last = (elm);                               \
 521         else                                                            \
 522                 (listelm)->field.cqe_next->field.cqe_prev = (elm);      \
 523         (listelm)->field.cqe_next = (elm);                              \
 524 } while (0)
 525
 526 #define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do {           \
 527         (elm)->field.cqe_next = (listelm);                              \
 528         (elm)->field.cqe_prev = (listelm)->field.cqe_prev;              \
 529         if ((listelm)->field.cqe_prev == CIRCLEQ_END(head))             \
 530                 (head)->cqh_first = (elm);                              \
 531         else                                                            \
 532                 (listelm)->field.cqe_prev->field.cqe_next = (elm);      \
 533         (listelm)->field.cqe_prev = (elm);                              \
 534 } while (0)
 535
 536 #define CIRCLEQ_INSERT_HEAD(head, elm, field) do {                      \
 537         (elm)->field.cqe_next = (head)->cqh_first;                      \
 538         (elm)->field.cqe_prev = CIRCLEQ_END(head);                      \
 539         if ((head)->cqh_last == CIRCLEQ_END(head))                      \
 540                 (head)->cqh_last = (elm);                               \
 541         else                                                            \
 542                 (head)->cqh_first->field.cqe_prev = (elm);              \
 543         (head)->cqh_first = (elm);                                      \
 544 } while (0)
 545
 546 #define CIRCLEQ_INSERT_TAIL(head, elm, field) do {                      \
 547         (elm)->field.cqe_next = CIRCLEQ_END(head);                      \
 548         (elm)->field.cqe_prev = (head)->cqh_last;                       \
 549         if ((head)->cqh_first == CIRCLEQ_END(head))                     \
 550                 (head)->cqh_first = (elm);                              \
 551         else                                                            \
 552                 (head)->cqh_last->field.cqe_next = (elm);               \
 553         (head)->cqh_last = (elm);                                       \
 554 } while (0)
 555
 556 #define CIRCLEQ_REMOVE(head, elm, field) do {                           \
 557         if ((elm)->field.cqe_next == CIRCLEQ_END(head))                 \
 558                 (head)->cqh_last = (elm)->field.cqe_prev;               \
 559         else                                                            \
 560                 (elm)->field.cqe_next->field.cqe_prev =                 \
 561                     (elm)->field.cqe_prev;                              \
 562         if ((elm)->field.cqe_prev == CIRCLEQ_END(head))                 \
 563                 (head)->cqh_first = (elm)->field.cqe_next;              \
 564         else                                                            \
 565                 (elm)->field.cqe_prev->field.cqe_next =                 \
 566                     (elm)->field.cqe_next;                              \
 567 } while (0)
 568
 569 #define CIRCLEQ_REPLACE(head, elm, elm2, field) do {                    \
 570         if (((elm2)->field.cqe_next = (elm)->field.cqe_next) ==         \
 571             CIRCLEQ_END(head))                                          \
 572                 (head).cqh_last = (elm2);                               \
 573         else                                                            \
 574                 (elm2)->field.cqe_next->field.cqe_prev = (elm2);        \
 575         if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) ==         \
 576             CIRCLEQ_END(head))                                          \
 577                 (head).cqh_first = (elm2);                              \
 578         else                                                            \
 579                 (elm2)->field.cqe_prev->field.cqe_next = (elm2);        \
 580 } while (0)
 581
 582 #endif  /* !_FAKE_QUEUE_H_ */