You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
251 lines
7.2 KiB
251 lines
7.2 KiB
#ifndef _LINUX_LIST_H |
|
#define _LINUX_LIST_H |
|
|
|
/* |
|
* 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) |
|
|
|
/* |
|
* Insert a new entry between two known consecutive entries. |
|
* |
|
* This is only for internal list manipulation where we know |
|
* the prev/next entries already! |
|
*/ |
|
static __inline void __list_add(struct list_head *lnew, |
|
struct list_head *prev, |
|
struct list_head *next) |
|
{ |
|
next->prev = lnew; |
|
lnew->next = next; |
|
lnew->prev = prev; |
|
prev->next = lnew; |
|
} |
|
|
|
/** |
|
* list_add - add a new entry |
|
* @new: new entry to be added |
|
* @head: list head to add it after |
|
* |
|
* Insert a new entry after the specified head. |
|
* This is good for implementing stacks. |
|
*/ |
|
static __inline void list_add(struct list_head *lnew, struct list_head *head) |
|
{ |
|
__list_add(lnew, head, head->next); |
|
} |
|
|
|
/** |
|
* list_add_tail - add a new entry |
|
* @new: new entry to be added |
|
* @head: list head to add it before |
|
* |
|
* Insert a new entry before the specified head. |
|
* This is useful for implementing queues. |
|
*/ |
|
static __inline void list_add_tail(struct list_head *lnew, struct list_head *head) |
|
{ |
|
__list_add(lnew, head->prev, head); |
|
} |
|
|
|
/* |
|
* Delete a list entry by making the prev/next entries |
|
* point to each other. |
|
* |
|
* This is only for internal list manipulation where we know |
|
* the prev/next entries already! |
|
*/ |
|
static __inline void __list_del(struct list_head *prev, struct list_head *next) |
|
{ |
|
next->prev = prev; |
|
prev->next = next; |
|
} |
|
|
|
/** |
|
* list_del - deletes entry from list. |
|
* @entry: the element to delete from the list. |
|
* Note: list_empty on entry does not return true after this, the entry is in an undefined state. |
|
*/ |
|
static __inline void list_del(struct list_head *entry) |
|
{ |
|
__list_del(entry->prev, entry->next); |
|
entry->next = (struct list_head *) 0; |
|
entry->prev = (struct list_head *) 0; |
|
} |
|
|
|
/** |
|
* list_del_init - deletes entry from list and reinitialize it. |
|
* @entry: the element to delete from the list. |
|
*/ |
|
static __inline void list_del_init(struct list_head *entry) |
|
{ |
|
__list_del(entry->prev, entry->next); |
|
INIT_LIST_HEAD(entry); |
|
} |
|
|
|
/** |
|
* list_move - delete from one list and add as another's head |
|
* @list: the entry to move |
|
* @head: the head that will precede our entry |
|
*/ |
|
static __inline void list_move(struct list_head *list, struct list_head *head) |
|
{ |
|
__list_del(list->prev, list->next); |
|
list_add(list, head); |
|
} |
|
|
|
/** |
|
* list_move_tail - delete from one list and add as another's tail |
|
* @list: the entry to move |
|
* @head: the head that will follow our entry |
|
*/ |
|
static __inline void list_move_tail(struct list_head *list, |
|
struct list_head *head) |
|
{ |
|
__list_del(list->prev, list->next); |
|
list_add_tail(list, head); |
|
} |
|
|
|
/** |
|
* list_empty - tests whether a list is empty |
|
* @head: the list to test. |
|
*/ |
|
static __inline int list_empty(struct list_head *head) |
|
{ |
|
return head->next == head; |
|
} |
|
|
|
static __inline void __list_splice(struct list_head *list, |
|
struct list_head *head) |
|
{ |
|
struct list_head *first = list->next; |
|
struct list_head *last = list->prev; |
|
struct list_head *at = head->next; |
|
|
|
first->prev = head; |
|
head->next = first; |
|
|
|
last->next = at; |
|
at->prev = last; |
|
} |
|
|
|
/** |
|
* list_splice - join two lists |
|
* @list: the new list to add. |
|
* @head: the place to add it in the first list. |
|
*/ |
|
static __inline void list_splice(struct list_head *list, struct list_head *head) |
|
{ |
|
if (!list_empty(list)) |
|
__list_splice(list, head); |
|
} |
|
|
|
/** |
|
* list_splice_init - join two lists and reinitialise the emptied list. |
|
* @list: the new list to add. |
|
* @head: the place to add it in the first list. |
|
* |
|
* The list at @list is reinitialised |
|
*/ |
|
static __inline void list_splice_init(struct list_head *list, |
|
struct list_head *head) |
|
{ |
|
if (!list_empty(list)) { |
|
__list_splice(list, head); |
|
INIT_LIST_HEAD(list); |
|
} |
|
} |
|
|
|
/** |
|
* 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 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_prev - iterate over a list backwards |
|
* @pos: the &struct list_head to use as a loop counter. |
|
* @head: the head for your list. |
|
*/ |
|
#define list_for_each_prev(pos, head) \ |
|
for (pos = (head)->prev; pos != (head); \ |
|
pos = pos->prev) |
|
|
|
/** |
|
* list_for_each_safe - iterate over a list safe against removal of list entry |
|
* @pos: the &struct list_head to use as a loop counter. |
|
* @n: another &struct list_head to use as temporary storage |
|
* @head: the head for your list. |
|
*/ |
|
#define list_for_each_safe(pos, n, head) \ |
|
for (pos = (head)->next, n = pos->next; pos != (head); \ |
|
pos = n, n = pos->next) |
|
|
|
/** |
|
* list_for_each_entry - iterate over list of given type |
|
* @pos: the type * to use as a loop counter. |
|
* @head: the head for your list. |
|
* @member: the name of the list_struct within the struct. |
|
*/ |
|
#define list_for_each_entry(pos, head, member, tpos) \ |
|
for (pos = list_entry((head)->next, tpos, member); \ |
|
&pos->member != (head); \ |
|
pos = list_entry(pos->member.next, tpos, member)) |
|
|
|
/** |
|
* list_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
|
* @pos: the type * to use as a loop counter. |
|
* @n: another type * to use as temporary storage |
|
* @head: the head for your list. |
|
* @member: the name of the list_struct within the struct. |
|
*/ |
|
#define list_for_each_entry_safe(pos, n, head, member, tpos, tn) \ |
|
for (pos = list_entry((head)->next, tpos, member), \ |
|
n = list_entry(pos->member.next, tpos, member); \ |
|
&pos->member != (head); \ |
|
pos = n, n = list_entry(n->member.next, tn, member)) |
|
|
|
/** |
|
* list_for_each_entry_continue - iterate over list of given type |
|
* continuing after existing point |
|
* @pos: the type * to use as a loop counter. |
|
* @head: the head for your list. |
|
* @member: the name of the list_struct within the struct. |
|
*/ |
|
#define list_for_each_entry_continue(pos, head, member, tpos) \ |
|
for (pos = list_entry(pos->member.next, tpos, member), \ |
|
prefetch(pos->member.next); \ |
|
&pos->member != (head); \ |
|
pos = list_entry(pos->member.next, tpos, member), \ |
|
prefetch(pos->member.next)) |
|
|
|
#endif
|
|
|