usr.bin/csup/queue.h

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)queue.h     8.5 (Berkeley) 8/20/94
  30  * $FreeBSD$
  31  *
  32  * $FreeBSD$
  33  */
  34
  35 #ifndef _QUEUE_H_
  36 #define _QUEUE_H_
  37
  38 #undef __offsetof
  39 #define __offsetof(type, field) ((size_t)(&((type *)0)->field))
  40
  41 /*
  42  * Singly-linked Tail queue declarations.
  43  */
  44 #undef STAILQ_HEAD
  45 #define STAILQ_HEAD(name, type)                                         \
  46 struct name {                                                           \
  47         struct type *stqh_first;/* first element */                     \
  48         struct type **stqh_last;/* addr of last next element */         \
  49 }
  50
  51 #undef STAILQ_HEAD_INITIALIZER
  52 #define STAILQ_HEAD_INITIALIZER(head)                                   \
  53         { NULL, &(head).stqh_first }
  54
  55 #undef STAILQ_ENTRY
  56 #define STAILQ_ENTRY(type)                                              \
  57 struct {                                                                \
  58         struct type *stqe_next; /* next element */                      \
  59 }
  60
  61 #undef STAILQ_EMPTY
  62 #define STAILQ_EMPTY(head)      ((head)->stqh_first == NULL)
  63
  64 #undef STAILQ_FIRST
  65 #define STAILQ_FIRST(head)      ((head)->stqh_first)
  66
  67 #undef STAILQ_FOREACH
  68 #define STAILQ_FOREACH(var, head, field)                                \
  69         for((var) = STAILQ_FIRST((head));                               \
  70            (var);                                                       \
  71            (var) = STAILQ_NEXT((var), field))
  72
  73 #undef STAILQ_FOREACH_SAFE
  74 #define STAILQ_FOREACH_SAFE(var, head, field, tvar)                     \
  75         for ((var) = STAILQ_FIRST((head));                              \
  76             (var) && ((tvar) = STAILQ_NEXT((var), field), 1);           \
  77             (var) = (tvar))
  78
  79 #undef STAILQ_INIT
  80 #define STAILQ_INIT(head) do {                                          \
  81         STAILQ_FIRST((head)) = NULL;                                    \
  82         (head)->stqh_last = &STAILQ_FIRST((head));                      \
  83 } while (0)
  84
  85 #undef STAILQ_INSERT_AFTER
  86 #define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do {               \
  87         if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\
  88                 (head)->stqh_last = &STAILQ_NEXT((elm), field);         \
  89         STAILQ_NEXT((tqelm), field) = (elm);                            \
  90 } while (0)
  91
  92 #undef STAILQ_INSERT_HEAD
  93 #define STAILQ_INSERT_HEAD(head, elm, field) do {                       \
  94         if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \
  95                 (head)->stqh_last = &STAILQ_NEXT((elm), field);         \
  96         STAILQ_FIRST((head)) = (elm);                                   \
  97 } while (0)
  98
  99 #undef STAILQ_INSERT_TAIL
 100 #define STAILQ_INSERT_TAIL(head, elm, field) do {                       \
 101         STAILQ_NEXT((elm), field) = NULL;                               \
 102         *(head)->stqh_last = (elm);                                     \
 103         (head)->stqh_last = &STAILQ_NEXT((elm), field);                 \
 104 } while (0)
 105
 106 #undef STAILQ_LAST
 107 #define STAILQ_LAST(head, type, field)                                  \
 108         (STAILQ_EMPTY((head)) ?                                         \
 109                 NULL :                                                  \
 110                 ((struct type *)(void *)                                \
 111                 ((char *)((head)->stqh_last) - __offsetof(struct type, field))))
 112
 113 #undef STAILQ_NEXT
 114 #define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next)
 115
 116 #undef STAILQ_REMOVE
 117 #define STAILQ_REMOVE(head, elm, type, field) do {                      \
 118         if (STAILQ_FIRST((head)) == (elm)) {                            \
 119                 STAILQ_REMOVE_HEAD((head), field);                      \
 120         }                                                               \
 121         else {                                                          \
 122                 struct type *curelm = STAILQ_FIRST((head));             \
 123                 while (STAILQ_NEXT(curelm, field) != (elm))             \
 124                         curelm = STAILQ_NEXT(curelm, field);            \
 125                 if ((STAILQ_NEXT(curelm, field) =                       \
 126                      STAILQ_NEXT(STAILQ_NEXT(curelm, field), field)) == NULL)\
 127                         (head)->stqh_last = &STAILQ_NEXT((curelm), field);\
 128         }                                                               \
 129 } while (0)
 130
 131 #undef STAILQ_REMOVE_HEAD
 132 #define STAILQ_REMOVE_HEAD(head, field) do {                            \
 133         if ((STAILQ_FIRST((head)) =                                     \
 134              STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL)         \
 135                 (head)->stqh_last = &STAILQ_FIRST((head));              \
 136 } while (0)
 137
 138 #undef STAILQ_REMOVE_HEAD_UNTIL
 139 #define STAILQ_REMOVE_HEAD_UNTIL(head, elm, field) do {                 \
 140         if ((STAILQ_FIRST((head)) = STAILQ_NEXT((elm), field)) == NULL) \
 141                 (head)->stqh_last = &STAILQ_FIRST((head));              \
 142 } while (0)
 143
 144 /*
 145  * List declarations.
 146  */
 147 #undef LIST_HEAD
 148 #define LIST_HEAD(name, type)                                           \
 149 struct name {                                                           \
 150         struct type *lh_first;  /* first element */                     \
 151 }
 152
 153 #undef LIST_HEAD_INITIALIZER
 154 #define LIST_HEAD_INITIALIZER(head)                                     \
 155         { NULL }
 156
 157 #undef LIST_ENTRY
 158 #define LIST_ENTRY(type)                                                \
 159 struct {                                                                \
 160         struct type *le_next;   /* next element */                      \
 161         struct type **le_prev;  /* address of previous next element */  \
 162 }
 163
 164 /*
 165  * List functions.
 166  */
 167
 168 #undef LIST_EMPTY
 169 #define LIST_EMPTY(head)        ((head)->lh_first == NULL)
 170
 171 #undef LIST_FIRST
 172 #define LIST_FIRST(head)        ((head)->lh_first)
 173
 174 #undef LIST_FOREACH
 175 #define LIST_FOREACH(var, head, field)                                  \
 176         for ((var) = LIST_FIRST((head));                                \
 177             (var);                                                      \
 178             (var) = LIST_NEXT((var), field))
 179
 180 #undef LIST_FOREACH_SAFE
 181 #define LIST_FOREACH_SAFE(var, head, field, tvar)                       \
 182         for ((var) = LIST_FIRST((head));                                \
 183             (var) && ((tvar) = LIST_NEXT((var), field), 1);             \
 184             (var) = (tvar))
 185
 186 #undef LIST_INIT
 187 #define LIST_INIT(head) do {                                            \
 188         LIST_FIRST((head)) = NULL;                                      \
 189 } while (0)
 190
 191 #undef LIST_INSERT_AFTER
 192 #define LIST_INSERT_AFTER(listelm, elm, field) do {                     \
 193         if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\
 194                 LIST_NEXT((listelm), field)->field.le_prev =            \
 195                     &LIST_NEXT((elm), field);                           \
 196         LIST_NEXT((listelm), field) = (elm);                            \
 197         (elm)->field.le_prev = &LIST_NEXT((listelm), field);            \
 198 } while (0)
 199
 200 #undef LIST_INSERT_BEFORE
 201 #define LIST_INSERT_BEFORE(listelm, elm, field) do {                    \
 202         (elm)->field.le_prev = (listelm)->field.le_prev;                \
 203         LIST_NEXT((elm), field) = (listelm);                            \
 204         *(listelm)->field.le_prev = (elm);                              \
 205         (listelm)->field.le_prev = &LIST_NEXT((elm), field);            \
 206 } while (0)
 207
 208 #undef LIST_INSERT_HEAD
 209 #define LIST_INSERT_HEAD(head, elm, field) do {                         \
 210         if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL)     \
 211                 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\
 212         LIST_FIRST((head)) = (elm);                                     \
 213         (elm)->field.le_prev = &LIST_FIRST((head));                     \
 214 } while (0)
 215
 216 #undef LIST_NEXT
 217 #define LIST_NEXT(elm, field)   ((elm)->field.le_next)
 218
 219 #undef LIST_REMOVE
 220 #define LIST_REMOVE(elm, field) do {                                    \
 221         if (LIST_NEXT((elm), field) != NULL)                            \
 222                 LIST_NEXT((elm), field)->field.le_prev =                \
 223                     (elm)->field.le_prev;                               \
 224         *(elm)->field.le_prev = LIST_NEXT((elm), field);                \
 225 } while (0)
 226
 227 #endif /* !_QUEUE_H_ */