diff options
Diffstat (limited to 'list.h')
| -rw-r--r-- | list.h | 292 |
1 files changed, 0 insertions, 292 deletions
@@ -1,292 +0,0 @@ -#ifndef __LIST_H -#define __LIST_H - -/* This file is from the Linux Kernel (include/linux/list.h) - * and modified by simply removing hardware prefetching of list items. - * Copyright, credits attributed to wherever they belong. - * Kulesh Shanmugasundaram (kulesh [squiggly] isis.poly.edu) - * Modified to round out my personal collection by John Anthony - */ - -/* - * 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. - */ - -#include <stdbool.h> - -struct list_head { - struct list_head *next; - struct list_head *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 *new, struct list_head *prev, - struct list_head *next) { - next->prev = new; - new->next = next; - new->prev = prev; - prev->next = new; -} - -/** - * 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 *new, struct list_head *head) { - __list_add(new, 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 *new, struct list_head *head) { - __list_add(new, 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. this - * is undefiend behaviour. - */ -static inline void -list_del(struct list_head *entry) { - __list_del(entry->prev, entry->next); - entry->next = (void *) 0; - entry->prev = (void *) 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 bool -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_reverse - 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_reverse(pos, head) \ - for (pos = (head)->prev; pos != (head); \ - pos = pos->prev) - -/** - * list_for_each_safe - iterate over a list safe against removal - * @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_safe_reverse - iterate list backwards safely - * @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_reverse(pos, n, head) \ - for (pos = (head)->prev, n = pos->prev; pos != (head); \ - pos = n, n = pos->prev) - -/** - * 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) \ - for (pos = list_entry((head)->next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) - -/** - * list_for_each_entry_reverse - iterate list of given type backwards - * @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_reverse(pos, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.prev, typeof(*pos), member)) - -/** - * list_for_each_entry_safe - iterate list entries safe against removal - * @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) \ - for (pos = list_entry((head)->next, typeof(*pos), member), \ - n = list_entry(pos->member.next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) - -/** - * list_for_each_entry_safe_reverse - as above but reverse iteration - * @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_reverse(pos, n, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member), \ - n = list_entry(pos->member.prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = n, n = list_entry(n->member.prev, typeof(*n), member)) - -/** - * list_len - count number of elements in the given list - * @head: the head for your list - * Note: This is a O(1) time operation and should be used sparingly - */ -static inline size_t -list_len(struct list_head *head) { - struct list_head *iter; - size_t count = 0; - - list_for_each(iter, head) - ++count; - return count; -} - -#endif |