hush/e2fsprogs/blkid/list.h
2006-09-11 01:34:21 +00:00

74 lines
2.3 KiB
C

/* vi: set sw=4 ts=4: */
#if !defined(_BLKID_LIST_H) && !defined(LIST_HEAD)
#define _BLKID_LIST_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* Simple doubly linked list implementation.
*
* Some of the internal functions ("__xxx") are useful when
* manipulating whole lists rather than single entries, as
* sometimes we already know the next/prev entries and we can
* generate better code by using them directly rather than
* using the generic single-entry routines.
*/
struct list_head {
struct list_head *next, *prev;
};
#define LIST_HEAD_INIT(name) { &(name), &(name) }
#define LIST_HEAD(name) \
struct list_head name = LIST_HEAD_INIT(name)
#define INIT_LIST_HEAD(ptr) do { \
(ptr)->next = (ptr); (ptr)->prev = (ptr); \
} while (0)
void __list_add(struct list_head * add, struct list_head * prev, struct list_head * next);
void list_add(struct list_head *add, struct list_head *head);
void list_add_tail(struct list_head *add, struct list_head *head);
void __list_del(struct list_head * prev, struct list_head * next);
void list_del(struct list_head *entry);
void list_del_init(struct list_head *entry);
int list_empty(struct list_head *head);
void list_splice(struct list_head *list, struct list_head *head);
/**
* list_entry - get the struct for this entry
* @ptr: the &struct list_head pointer.
* @type: the type of the struct this is embedded in.
* @member: the name of the list_struct within the struct.
*/
#define list_entry(ptr, type, member) \
((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
/**
* list_for_each - iterate over elements in a list
* @pos: the &struct list_head to use as a loop counter.
* @head: the head for your list.
*/
#define list_for_each(pos, head) \
for (pos = (head)->next; pos != (head); pos = pos->next)
/**
* list_for_each_safe - iterate over elements in a list, but don't dereference
* pos after the body is done (in case it is freed)
* @pos: the &struct list_head to use as a loop counter.
* @pnext: the &struct list_head to use as a pointer to the next item.
* @head: the head for your list (not included in iteration).
*/
#define list_for_each_safe(pos, pnext, head) \
for (pos = (head)->next, pnext = pos->next; pos != (head); \
pos = pnext, pnext = pos->next)
#ifdef __cplusplus
}
#endif
#endif /* _BLKID_LIST_H */