hostside/dliste.h

   1 /*
   2  * dlist.h
   3  * Doubly linked lists
   4  *
   5  * This file is part of epithet, a DNS nameserver.
   6  * epithet is Copyright 2001 Ian Jackson.
   7  *
   8  * epithet is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program and documentation is distributed in the hope that it
  14  * will be useful, but without any warranty; without even the implied
  15  * warranty of merchantability or fitness for a particular
  16  * purpose. See the GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with epithet; if not, write to the Free Software Foundation,
  20  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA, or email
  21  * epithet-maint@chiark.greenend.org.uk.
  22  */
  23
  24 #ifndef DLIST_H
  25 #define DLIST_H
  26
  27
  28 #define DLIST_NNODE(nodetype,linktag) struct linktag { nodetype *next, *back; }
  29 #define DLIST_NODE(nodetype)          DLIST_NNODE(nodetype, )
  30
  31 #define DLIST1_PREPEND(head,node,linkmemb)                                    \
  32   ((void)((node)->linkmemb.next= (head),                                      \
  33           (node)->linkmemb.back= 0,                                           \
  34           ((head) ? (head)->linkmemb.back= (node) : 0),                       \
  35           (head)= (node)))
  36
  37 #define DLIST1_REMOVE(head,node,link)                                         \
  38   ((void)                                                                     \
  39    ((node)->link.next ? ((node)->link.next->link.back= (node)->link.back) :0, \
  40     (node)->link.back ? ((node)->link.back->link.next= (node)->link.next)     \
  41                       : ((head)=                       (node)->link.next)))
  42
  43
  44 #define DLIST2_NHEAD(nodetype,listtag) struct listtag { nodetype *head,*tail; }
  45 #define DLIST2_HEAD(nodetype)          DLIST2_NHEAD(nodetype, )
  46
  47 #define DLIST2_INIT(list) ((list).head= (list).tail= 0)
  48
  49 #define DLIST2_REMOVE(list,node,link)                                         \
  50   ((void)                                                                     \
  51    (((node)->link.back ? ((node)->link.back->link.next= (node)->link.next)    \
  52                        : (                 (list).head= (node)->link.next)),  \
  53     ((node)->link.next ? ((node)->link.next->link.back= (node)->link.back)    \
  54                        : (                 (list).tail= (node)->link.back))))
  55
  56 #define DLIST2_APPEND(list,node,link)                   \
  57   ((void)                                               \
  58    ((node)->link.next= 0,                               \
  59     (node)->link.back= (list).tail,                     \
  60     ((list).tail ? ((list).tail->link.next= (node))     \
  61                  : ((list).head= (node))),              \
  62     (list).tail= (node)))
  63
  64 #define DLIST2_PREPEND(list,node,link)                  \
  65   ((void)                                               \
  66    ((node)->link.next= (list).head,                     \
  67     (node)->link.back= 0,                               \
  68     ((list).head ? ((list).head->link.back= (node))     \
  69                  : ((list).tail= (node))),              \
  70     (list).head= (node)))
  71
  72 #define DLIST2_INSERT_BEFORE(list,newnode,link,refnode) \
  73   ((void)                                               \
  74    ((newnode)->link.next= (refnode),                    \
  75     (newnode)->link.back= (refnode)->link.back,         \
  76     ((refnode)->link.back                               \
  77        ? ((refnode)->link.back->link.next= (newnode))   \
  78        : ((list).head= (newnode))),                     \
  79     (refnode)->link.back= (newnode)))
  80
  81 #define DLIST2_INSERT_AFTER(list,newnode,link,refnode)  \
  82   ((void)                                               \
  83    ((newnode)->link.back= (refnode),                    \
  84     (newnode)->link.next= (refnode)->link.next,         \
  85     ((refnode)->link.next                               \
  86        ? ((refnode)->link.next->link.back= (newnode))   \
  87        : ((list).tail= (newnode))),                     \
  88     (refnode)->link.next= (newnode)))))
  89
  90 #endif /*DLIST_H*/