#ifndef _LINUX_HLIST_H
#define _LINUX_HLIST_H
/*
* Double linked lists with a single pointer list head.
* Mostly useful for hash tables where the two pointer list head is
* too wasteful.
* You lose the ability to access the tail in O(1).
*/
struct hlist_head {
struct hlist_node *first;
};
struct hlist_node {
struct hlist_node *next, **pprev;
};
#ifndef offsetof
#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
#endif
#ifndef container_of
/**
* container_of - cast a member of a structure out to the containing structure
* @ptr: the pointer to the member.
* @type: the type of the container struct this is embedded in.
* @member: the name of the member within the struct.
*
*/
#define container_of(ptr, type, member) ({ \
)->member) * __mptr = (ptr); \
(type *)((char *)__mptr - offsetof(type, member)); })
#endif
#define HLIST_HEAD_INIT { .first = NULL }
#define HLIST_HEAD(name) struct hlist_head name = { .first = NULL }
#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
static inline void INIT_HLIST_NODE(struct hlist_node *h)
{
h->next = NULL;
h->pprev = NULL;
}
static inline int hlist_unhashed(const struct hlist_node *h)
{
return !h->pprev;
}
static inline int hlist_empty(const struct hlist_head *h)
{
return !h->first;
}
static inline void __hlist_del(struct hlist_node *n)
{
struct hlist_node *next = n->next;
struct hlist_node **pprev = n->pprev;
*pprev = next;
if (next)
next->pprev = pprev;
}
static inline void hlist_del(struct hlist_node *n)
{
__hlist_del(n);
INIT_HLIST_NODE(n);
}
static inline void hlist_del_init(struct hlist_node *n)
{
if (!hlist_unhashed(n)) {
__hlist_del(n);
INIT_HLIST_NODE(n);
}
}
static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
{
struct hlist_node *first = h->first;
n->next = first;
if (first)
first->pprev = &n->next;
h->first = n;
n->pprev = &h->first;
}
/* next must be != NULL */
static inline void hlist_add_before(struct hlist_node *n,
struct hlist_node *next)
{
n->pprev = next->pprev;
n->next = next;
next->pprev = &n->next;
*(n->pprev) = n;
}
static inline void hlist_add_after(struct hlist_node *n,
struct hlist_node *next)
{
next->next = n->next;
n->next = next;
next->pprev = &n->next;
if(next->next)
next->next->pprev = &next->next;
}
/* after that we'll appear to be on some hlist and hlist_del will work */
static inline void hlist_add_fake(struct hlist_node *n)
{
n->pprev = &n->next;
}
/*
* Move a list from one list head to another. Fixup the pprev
* reference of the first entry if it exists.
*/
static inline void hlist_move_list(struct hlist_head *old,
struct hlist_head *new)
{
new->first = old->first;
if (new->first)
new->first->pprev = &new->first;
old->first = NULL;
}
#define hlist_entry(ptr, type, member) container_of(ptr,type,member)
#define hlist_for_each(pos, head) \
for (pos = (head)->first; pos ; pos = pos->next)
#define hlist_for_each_safe(pos, n, head) \
; }); \
pos = n)
/**
* hlist_for_each_entry - iterate over list of given type
* @tpos: the type * to use as a loop cursor.
* @pos: the &struct hlist_node to use as a loop cursor.
* @head: the head for your list.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry(tpos, pos, head, member) \
for (pos = (head)->first; \
pos && \
({ tpos = hlist_entry(pos, ;}); \
pos = pos->next)
/**
* hlist_for_each_entry_continue - iterate over a hlist continuing after current point
* @tpos: the type * to use as a loop cursor.
* @pos: the &struct hlist_node to use as a loop cursor.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_continue(tpos, pos, member) \
for (pos = (pos)->next; \
pos && \
({ tpos = hlist_entry(pos, ;}); \
pos = pos->next)
/**
* hlist_for_each_entry_from - iterate over a hlist continuing from current point
* @tpos: the type * to use as a loop cursor.
* @pos: the &struct hlist_node to use as a loop cursor.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_from(tpos, pos, member) \
for (; pos && \
({ tpos = hlist_entry(pos, ;}); \
pos = pos->next)
/**
* hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
* @tpos: the type * to use as a loop cursor.
* @pos: the &struct hlist_node to use as a loop cursor.
* @n: another &struct hlist_node to use as temporary storage
* @head: the head for your list.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_safe(tpos, pos, n, head, member) \
for (pos = (head)->first; \
pos && ({ n = pos->next; ; }) && \
({ tpos = hlist_entry(pos, ;}); \
pos = n)
#endif