/contrib/bind9/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 */