diff options
Diffstat (limited to 'include/list.h')
-rw-r--r-- | include/list.h | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/include/list.h b/include/list.h new file mode 100644 index 0000000000..749c727175 --- /dev/null +++ b/include/list.h @@ -0,0 +1,117 @@ +/* Copyright (C) 2002-2014 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _LIST_H + +#ifndef __need_list_t +# define _LIST_H 1 +#endif + +/* The definitions of this file are adopted from those which can be + found in the Linux kernel headers to enable people familiar with + the latter find their way in these sources as well. */ + + +#if defined __need_list_t || defined _LIST_H +# ifndef __list_t_defined +# define __list_t_defined +/* Basic type for the double-link list. */ +typedef struct list_head +{ + struct list_head *next; + struct list_head *prev; +} list_t; +# endif +# undef __need_list_t +#endif + +#ifdef _LIST_H + +# include <atomic.h> + +/* Define a variable with the head and tail of the list. */ +# define LIST_HEAD(name) \ + list_t name = { &(name), &(name) } + +/* Initialize a new list head. */ +# define INIT_LIST_HEAD(ptr) \ + (ptr)->next = (ptr)->prev = (ptr) + + +/* Add new element at the head of the list. */ +static inline void +list_add (list_t *newp, list_t *head) +{ + newp->next = head->next; + newp->prev = head; + head->next->prev = newp; + atomic_write_barrier (); + head->next = newp; +} + + +/* Remove element from list. */ +static inline void +list_del (list_t *elem) +{ + elem->next->prev = elem->prev; + elem->prev->next = elem->next; +} + + +/* Join two lists. */ +static inline void +list_splice (list_t *add, list_t *head) +{ + /* Do nothing if the list which gets added is empty. */ + if (add != add->next) + { + add->next->prev = head; + add->prev->next = head->next; + head->next->prev = add->prev; + head->next = add->next; + } +} + + +/* Get typed element from list at a given position. */ +# define list_entry(ptr, type, member) \ + ((type *) ((char *) (ptr) - (unsigned long) (&((type *) 0)->member))) + + + +/* Iterate forward over the elements of the list. */ +# define list_for_each(pos, head) \ + for (pos = (head)->next; pos != (head); pos = pos->next) + + +/* Iterate forward over the elements of the list. */ +# define list_for_each_prev(pos, head) \ + for (pos = (head)->prev; pos != (head); pos = pos->prev) + + +/* Iterate backwards over the elements list. The list elements can be + removed from the list while doing this. */ +# define list_for_each_prev_safe(pos, p, head) \ + for (pos = (head)->prev, p = pos->prev; \ + pos != (head); \ + pos = p, p = pos->prev) + +#endif /* _LIST_H */ + +#endif /* list.h */ |