3 * - macros for handling doubly linked lists
6 * This file is part of adns, which is Copyright Ian Jackson
7 * and contributors (see the file INSTALL for full details).
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 3, or (at your option)
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software Foundation.
23 #ifndef ADNS_DLIST_H_INCLUDED
24 #define ADNS_DLIST_H_INCLUDED
26 #define LIST_INIT(list) ((list).head= (list).tail= 0)
27 #define LINK_INIT(link) ((link).next= (link).back= 0)
29 #define LIST_UNLINK_PART(list,node,part) \
31 if ((node)->part back) (node)->part back->part next= (node)->part next; \
32 else (list).head= (node)->part next; \
33 if ((node)->part next) (node)->part next->part back= (node)->part back; \
34 else (list).tail= (node)->part back; \
37 #define LIST_LINK_TAIL_PART(list,node,part) \
39 (node)->part next= 0; \
40 (node)->part back= (list).tail; \
41 if ((list).tail) (list).tail->part next= (node); \
42 else (list).head= (node); \
43 (list).tail= (node); \
46 #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
47 #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)