contrib/bind-9.5.2/lib/lwres/include/lwres/list.h

   1 /*
   2  * Copyright (C) 2004-2007  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1997-2001  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: list.h,v 1.14 2007/06/19 23:47:23 tbox Exp $ */
  19
  20 #ifndef LWRES_LIST_H
  21 #define LWRES_LIST_H 1
  22
  23 /*! \file lwres/list.h */
  24
  25 #define LWRES_LIST(type) struct { type *head, *tail; }
  26 #define LWRES_LIST_INIT(list) \
  27         do { (list).head = NULL; (list).tail = NULL; } while (0)
  28
  29 #define LWRES_LINK(type) struct { type *prev, *next; }
  30 #define LWRES_LINK_INIT(elt, link) \
  31         do { \
  32                 (elt)->link.prev = (void *)(-1); \
  33                 (elt)->link.next = (void *)(-1); \
  34         } while (0)
  35 #define LWRES_LINK_LINKED(elt, link) \
  36         ((void *)((elt)->link.prev) != (void *)(-1))
  37
  38 #define LWRES_LIST_HEAD(list) ((list).head)
  39 #define LWRES_LIST_TAIL(list) ((list).tail)
  40 #define LWRES_LIST_EMPTY(list) LWRES_TF((list).head == NULL)
  41
  42 #define LWRES_LIST_PREPEND(list, elt, link) \
  43         do { \
  44                 if ((list).head != NULL) \
  45                         (list).head->link.prev = (elt); \
  46                 else \
  47                         (list).tail = (elt); \
  48                 (elt)->link.prev = NULL; \
  49                 (elt)->link.next = (list).head; \
  50                 (list).head = (elt); \
  51         } while (0)
  52
  53 #define LWRES_LIST_APPEND(list, elt, link) \
  54         do { \
  55                 if ((list).tail != NULL) \
  56                         (list).tail->link.next = (elt); \
  57                 else \
  58                         (list).head = (elt); \
  59                 (elt)->link.prev = (list).tail; \
  60                 (elt)->link.next = NULL; \
  61                 (list).tail = (elt); \
  62         } while (0)
  63
  64 #define LWRES_LIST_UNLINK(list, elt, link) \
  65         do { \
  66                 if ((elt)->link.next != NULL) \
  67                         (elt)->link.next->link.prev = (elt)->link.prev; \
  68                 else \
  69                         (list).tail = (elt)->link.prev; \
  70                 if ((elt)->link.prev != NULL) \
  71                         (elt)->link.prev->link.next = (elt)->link.next; \
  72                 else \
  73                         (list).head = (elt)->link.next; \
  74                 (elt)->link.prev = (void *)(-1); \
  75                 (elt)->link.next = (void *)(-1); \
  76         } while (0)
  77
  78 #define LWRES_LIST_PREV(elt, link) ((elt)->link.prev)
  79 #define LWRES_LIST_NEXT(elt, link) ((elt)->link.next)
  80
  81 #define LWRES_LIST_INSERTBEFORE(list, before, elt, link) \
  82         do { \
  83                 if ((before)->link.prev == NULL) \
  84                         LWRES_LIST_PREPEND(list, elt, link); \
  85                 else { \
  86                         (elt)->link.prev = (before)->link.prev; \
  87                         (before)->link.prev = (elt); \
  88                         (elt)->link.prev->link.next = (elt); \
  89                         (elt)->link.next = (before); \
  90                 } \
  91         } while (0)
  92
  93 #define LWRES_LIST_INSERTAFTER(list, after, elt, link) \
  94         do { \
  95                 if ((after)->link.next == NULL) \
  96                         LWRES_LIST_APPEND(list, elt, link); \
  97                 else { \
  98                         (elt)->link.next = (after)->link.next; \
  99                         (after)->link.next = (elt); \
 100                         (elt)->link.next->link.prev = (elt); \
 101                         (elt)->link.prev = (after); \
 102                 } \
 103         } while (0)
 104
 105 #define LWRES_LIST_APPENDLIST(list1, list2, link) \
 106         do { \
 107                 if (LWRES_LIST_EMPTY(list1)) \
 108                         (list1) = (list2); \
 109                 else if (!LWRES_LIST_EMPTY(list2)) { \
 110                         (list1).tail->link.next = (list2).head; \
 111                         (list2).head->link.prev = (list1).tail; \
 112                         (list1).tail = (list2).tail; \
 113                 } \
 114                 (list2).head = NULL; \
 115                 (list2).tail = NULL; \
 116         } while (0)
 117
 118 #define LWRES_LIST_ENQUEUE(list, elt, link) LWRES_LIST_APPEND(list, elt, link)
 119 #define LWRES_LIST_DEQUEUE(list, elt, link) LWRES_LIST_UNLINK(list, elt, link)
 120
 121 #endif /* LWRES_LIST_H */