/* * Copyright (c) 1997,1999 by Internet Software Consortium. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS * SOFTWARE. */ #ifndef LIST_H #define LIST_H 1 #include #define LIST(type) struct { type *head, *tail; } #define INIT_LIST(list) \ do { (list).head = NULL; (list).tail = NULL; } while (0) #define LINK(type) struct { type *prev, *next; } #define INIT_LINK_TYPE(elt, link, type) \ do { \ (elt)->link.prev = (type *)(-1); \ (elt)->link.next = (type *)(-1); \ } while (0) #define INIT_LINK(elt, link) \ INIT_LINK_TYPE(elt, link, void) #define LINKED(elt, link) ((void *)((elt)->link.prev) != (void *)(-1)) #define HEAD(list) ((list).head) #define TAIL(list) ((list).tail) #define EMPTY(list) ((list).head == NULL) #define PREPEND(list, elt, link) \ do { \ INSIST(!LINKED(elt, link));\ if ((list).head != NULL) \ (list).head->link.prev = (elt); \ else \ (list).tail = (elt); \ (elt)->link.prev = NULL; \ (elt)->link.next = (list).head; \ (list).head = (elt); \ } while (0) #define APPEND(list, elt, link) \ do { \ INSIST(!LINKED(elt, link));\ if ((list).tail != NULL) \ (list).tail->link.next = (elt); \ else \ (list).head = (elt); \ (elt)->link.prev = (list).tail; \ (elt)->link.next = NULL; \ (list).tail = (elt); \ } while (0) #define UNLINK_TYPE(list, elt, link, type) \ do { \ INSIST(LINKED(elt, link));\ if ((elt)->link.next != NULL) \ (elt)->link.next->link.prev = (elt)->link.prev; \ else \ (list).tail = (elt)->link.prev; \ if ((elt)->link.prev != NULL) \ (elt)->link.prev->link.next = (elt)->link.next; \ else \ (list).head = (elt)->link.next; \ INIT_LINK_TYPE(elt, link, type); \ } while (0) #define UNLINK(list, elt, link) \ UNLINK_TYPE(list, elt, link, void) #define PREV(elt, link) ((elt)->link.prev) #define NEXT(elt, link) ((elt)->link.next) #define INSERT_BEFORE(list, before, elt, link) \ do { \ INSIST(!LINKED(elt, link));\ if ((before)->link.prev == NULL) \ PREPEND(list, elt, link); \ else { \ (elt)->link.prev = (before)->link.prev; \ (before)->link.prev = (elt); \ (elt)->link.prev->link.next = (elt); \ (elt)->link.next = (before); \ } \ } while (0) #define INSERT_AFTER(list, after, elt, link) \ do { \ INSIST(!LINKED(elt, link));\ if ((after)->link.next == NULL) \ APPEND(list, elt, link); \ else { \ (elt)->link.next = (after)->link.next; \ (after)->link.next = (elt); \ (elt)->link.next->link.prev = (elt); \ (elt)->link.prev = (after); \ } \ } while (0) #define ENQUEUE(list, elt, link) APPEND(list, elt, link) #define DEQUEUE(list, elt, link) UNLINK(list, elt, link) #endif /* LIST_H */