unix4lyfe git - darkstat-debian/blob - queue.h

   1 /* This is a stripped down version of FreeBSD's
   2  * src/sys/sys/queue.h,v 1.60.2.1
   3  *
   4  * The original file's license:
   5  *
   6  * Copyright (c) 1991, 1993
   7  *      The Regents of the University of California.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #define STAILQ_HEAD(name, type)                                         \
  35 struct name {                                                           \
  36         struct type *stqh_first;/* first element */                     \
  37         struct type **stqh_last;/* addr of last next element */         \
  38 }
  39
  40 #define STAILQ_HEAD_INITIALIZER(head)                                   \
  41         { NULL, &(head).stqh_first }
  42
  43 #define STAILQ_ENTRY(type)                                              \
  44 struct {                                                                \
  45         struct type *stqe_next; /* next element */                      \
  46 }
  47
  48 #define STAILQ_EMPTY(head)      ((head)->stqh_first == NULL)
  49
  50 #define STAILQ_FIRST(head)      ((head)->stqh_first)
  51
  52 #define STAILQ_FOREACH(var, head, field)                                \
  53         for((var) = STAILQ_FIRST((head));                               \
  54            (var);                                                       \
  55            (var) = STAILQ_NEXT((var), field))
  56
  57 #define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next)
  58
  59 #ifdef STAILQ_INSERT_TAIL
  60 #undef STAILQ_INSERT_TAIL
  61 #endif
  62
  63 #define STAILQ_INSERT_TAIL(head, elm, field) do {                       \
  64         STAILQ_NEXT((elm), field) = NULL;                               \
  65         *(head)->stqh_last = (elm);                                     \
  66         (head)->stqh_last = &STAILQ_NEXT((elm), field);                 \
  67 } while (0)
  68
  69 #ifdef STAILQ_REMOVE_HEAD
  70 #undef STAILQ_REMOVE_HEAD
  71 #endif
  72
  73 #define STAILQ_REMOVE_HEAD(head, field) do {                            \
  74         if ((STAILQ_FIRST((head)) =                                     \
  75              STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL)         \
  76                 (head)->stqh_last = &STAILQ_FIRST((head));              \
  77 } while (0)
  78
  79 #undef LIST_HEAD
  80 #define LIST_HEAD(name, type)                                           \
  81 struct name {                                                           \
  82         struct type *lh_first;  /* first element */                     \
  83 }
  84
  85 #undef LIST_HEAD_INITIALIZER
  86 #define LIST_HEAD_INITIALIZER(head)                                     \
  87         { NULL }
  88
  89 #undef LIST_ENTRY
  90 #define LIST_ENTRY(type)                                                \
  91 struct {                                                                \
  92         struct type *le_next;   /* next element */                      \
  93         struct type **le_prev;  /* address of previous next element */  \
  94 }
  95
  96 #undef LIST_FIRST
  97 #define LIST_FIRST(head)        ((head)->lh_first)
  98
  99 #undef LIST_FOREACH
 100 #define LIST_FOREACH(var, head, field)                                  \
 101         for ((var) = LIST_FIRST((head));                                \
 102             (var);                                                      \
 103             (var) = LIST_NEXT((var), field))
 104
 105 #undef LIST_FOREACH_SAFE
 106 #define LIST_FOREACH_SAFE(var, head, field, tvar)                       \
 107     for ((var) = LIST_FIRST((head));                                    \
 108         (var) && ((tvar) = LIST_NEXT((var), field), 1);                 \
 109         (var) = (tvar))
 110
 111 #undef LIST_INIT
 112 #define LIST_INIT(head) do {                                            \
 113         LIST_FIRST((head)) = NULL;                                      \
 114 } while (0)
 115
 116 #undef LIST_INSERT_HEAD
 117 #define LIST_INSERT_HEAD(head, elm, field) do {                         \
 118         if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL)     \
 119                 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\
 120         LIST_FIRST((head)) = (elm);                                     \
 121         (elm)->field.le_prev = &LIST_FIRST((head));                     \
 122 } while (0)
 123
 124 #undef LIST_NEXT
 125 #define LIST_NEXT(elm, field)   ((elm)->field.le_next)
 126
 127 #undef LIST_REMOVE
 128 #define LIST_REMOVE(elm, field) do {                                    \
 129         if (LIST_NEXT((elm), field) != NULL)                            \
 130                 LIST_NEXT((elm), field)->field.le_prev =                \
 131                     (elm)->field.le_prev;                               \
 132         *(elm)->field.le_prev = LIST_NEXT((elm), field);                \
 133 } while (0)