mdw@git.distorted.org.uk Git - adns/blob - src/dlist.h

   1 /*
   2  * dlist.h
   3  * - macros for handling doubly linked lists
   4  */
   5 /*
   6  *  This file is part of adns, which is
   7  *    Copyright (C) 1997-2000,2003,2006,2014  Ian Jackson
   8  *    Copyright (C) 1999-2000,2003,2006  Tony Finch
   9  *    Copyright (C) 1991 Massachusetts Institute of Technology
  10  *  (See the file INSTALL for full details.)
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 3, or (at your option)
  15  *  any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful,
  18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  *  GNU General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License
  23  *  along with this program; if not, write to the Free Software Foundation.
  24  */
  25
  26 #ifndef ADNS_DLIST_H_INCLUDED
  27 #define ADNS_DLIST_H_INCLUDED
  28
  29 #define LIST_INIT(list) ((list).head= (list).tail= 0)
  30 #define LINK_INIT(link) ((link).next= (link).back= 0)
  31
  32 #define LIST_UNLINK_PART(list,node,part)                                    \
  33   do {                                                                      \
  34     if ((node)->part back) (node)->part back->part next= (node)->part next; \
  35       else                                  (list).head= (node)->part next; \
  36     if ((node)->part next) (node)->part next->part back= (node)->part back; \
  37       else                                  (list).tail= (node)->part back; \
  38   } while(0)
  39
  40 #define LIST_LINK_TAIL_PART(list,node,part)             \
  41   do {                                                  \
  42     (node)->part next= 0;                               \
  43     (node)->part back= (list).tail;                     \
  44     if ((list).tail) (list).tail->part next= (node);    \
  45     else (list).head= (node);                           \
  46     (list).tail= (node);                                \
  47   } while(0)
  48
  49 #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
  50 #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
  51
  52 #endif