dockapps/wmfu/list.h

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/*
* Copyright (c) 2007 Daniel Borca All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef LIST_H_included
#define LIST_H_included
/**
* Remove an element from list.
*
* \param elem element to remove.
*/
#define list_remove(elem) \
do { \
(elem)->next->prev = (elem)->prev; \
(elem)->prev->next = (elem)->next; \
} while (0)
/**
* Insert an element to the list head.
*
* \param list list.
* \param elem element to insert.
*/
#define list_prepend(list, elem) \
do { \
(elem)->prev = list; \
(elem)->next = (list)->next; \
(list)->next->prev = elem; \
(list)->next = elem; \
} while(0)
/**
* Insert an element to the list tail.
*
* \param list list.
* \param elem element to insert.
*/
#define list_append(list, elem) \
do { \
(elem)->next = list; \
(elem)->prev = (list)->prev; \
(list)->prev->next = elem; \
(list)->prev = elem; \
} while(0)
/**
* Make a empty list empty.
*
* \param sentinel list (sentinel element).
*/
#define list_create(sentinel) \
do { \
(sentinel)->next = sentinel; \
(sentinel)->prev = sentinel; \
} while (0)
/**
* Get list first element.
*
* \param list list.
*
* \return pointer to first element.
*/
#define list_first(list) ((list)->next)
/**
* Get list last element.
*
* \param list list.
*
* \return pointer to last element.
*/
#define list_last(list) ((list)->prev)
/**
* Get next element.
*
* \param elem element.
*
* \return pointer to next element.
*/
#define list_next(elem) ((elem)->next)
/**
* Get previous element.
*
* \param elem element.
*
* \return pointer to previous element.
*/
#define list_prev(elem) ((elem)->prev)
/**
* Test whether element is at end of the list.
*
* \param list list.
* \param elem element.
*
* \return non-zero if element is at end of list, or zero otherwise.
*/
#define list_at_end(list, elem) ((elem) == (list))
/**
* Test if a list is empty.
*
* \param list list.
*
* \return non-zero if list empty, or zero otherwise.
*/
#define list_is_empty(list) ((list)->next == (list))
/**
* Walk through the elements of a list.
*
* \param ptr pointer to the current element.
* \param list list.
*
* \note It should be followed by a { } block or a single statement, as in a \c
* for loop.
*/
#define list_foreach(ptr, list)\
for (ptr = (list)->next; ptr != list; ptr = (ptr)->next)
/**
* Walk through the elements of a list.
*
* Same as #foreach but lets you unlink the current value during a list
* traversal. Useful for freeing a list, element by element.
*
* \param ptr pointer to the current element.
* \param t temporary pointer.
* \param list list.
*
* \note It should be followed by a { } block or a single statement, as in a \c
* for loop.
*/
#define list_foreach_s(ptr, t, list)\
for (ptr = (list)->next, t = (ptr)->next; list != ptr; ptr = t, t = (t)->next)
#endif