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#ifndef _LIST_H
#define _LIST_H 1
/* 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.
*/
/* Basic type for the double-link list.
*/
typedef struct list_head
{
struct list_head *next;
struct list_head *prev;
} list_t;
/* 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)
{
head->next->prev = newp;
newp->next = head->next;
newp->prev = head;
head->next = newp;
}
/* Add new element at the tail of the list.
*/
static inline void
list_add_tail (list_t *newp, list_t *head)
{
head->prev->next = newp;
newp->next = head;
newp->prev = head->prev;
head->prev = 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 */