libexec/httpd/netbsd_queue.h

   1 /*      $eterna: queue.h,v 1.6 2009/04/18 08:36:03 mrg Exp $    */
   2 /* from: NetBSD: queue.h,v 1.51 2009/03/11 06:51:53 mrg 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 #ifndef _SYS_QUEUE_H_
  36 #define _SYS_QUEUE_H_
  37
  38 /*
  39  * Simple queue definitions.
  40  */
  41 #define SIMPLEQ_HEAD(name, type)                                        \
  42 struct name {                                                           \
  43         struct type *sqh_first; /* first element */                     \
  44         struct type **sqh_last; /* addr of last next element */         \
  45 }
  46
  47 #define SIMPLEQ_ENTRY(type)                                             \
  48 struct {                                                                \
  49         struct type *sqe_next;  /* next element */                      \
  50 }
  51
  52 /*
  53  * Simple queue functions.
  54  */
  55 #define SIMPLEQ_INIT(head) do {                                         \
  56         (head)->sqh_first = NULL;                                       \
  57         (head)->sqh_last = &(head)->sqh_first;                          \
  58 } while (/*CONSTCOND*/0)
  59
  60 #define SIMPLEQ_INSERT_TAIL(head, elm, field) do {                      \
  61         (elm)->field.sqe_next = NULL;                                   \
  62         *(head)->sqh_last = (elm);                                      \
  63         (head)->sqh_last = &(elm)->field.sqe_next;                      \
  64 } while (/*CONSTCOND*/0)
  65
  66 #define SIMPLEQ_FOREACH(var, head, field)                               \
  67         for ((var) = ((head)->sqh_first);                               \
  68                 (var);                                                  \
  69                 (var) = ((var)->field.sqe_next))
  70
  71 #define SIMPLEQ_FOREACH_SAFE(var, head, field, next)                    \
  72         for ((var) = ((head)->sqh_first);                               \
  73                 (var) && ((next = ((var)->field.sqe_next)), 1);         \
  74                 (var) = (next))
  75
  76 /*
  77  * Simple queue access methods.
  78  */
  79 #define SIMPLEQ_FIRST(head)             ((head)->sqh_first)
  80 #define SIMPLEQ_NEXT(elm, field)        ((elm)->field.sqe_next)
  81
  82 #endif  /* !_SYS_QUEUE_H_ */