Simple doubly linked lists

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Detailed Description

The simplest kind of linked list is a singly-linked list, which has one link per node. This link points to the next node in the list, or to a null value or empty list if it is the final node; e.g. 12 -> 99 -> 37 -> NULL.

A more sophisticated kind of linked list is a doubly-linked list. Each node has two links: one points to the previous node, or points to a null value or empty list if it is the first node; and one points to the next, or points to a null value or empty list if it is the final node; e.g. NULL <- 26 <-> 56 <-> 46 -> NULL.

The list family of functions and macros provide routines to create a list, add, move or remove elements and iterate over the list.

Data Structures
struct	list_head
	list head More...
Defines
#define	container_of(ptr, type, member)   ((type *)((char *)(ptr) - offsetof(type, member)))
	get container of list head
#define	LIST_NODE_ALLOC(NAME)   NAME = mem_alloc(sizeof(*NAME))
#define	list_entry(ptr, type, member)   container_of(ptr, type, member)
	get the struct for this entry
#define	list_for_each(pos, head)   for (pos = (head)->next; pos != (head); pos = pos->next)
	iterate over a list
#define	list_for_each_prev(pos, head)   for (pos = (head)->prev; pos != (head); pos = pos->prev)
	iterate over a list backwards
#define	list_for_each_safe(pos, n, head)
	iterate over a list safe against removal of list entry
#define	list_for_each_entry(pos, head, member)
	iterate over list of given type
#define	list_for_each_entry_reverse(pos, head, member)
	iterate backwards over list of given type.
#define	list_for_each_entry_safe(pos, n, head, member)
	iterate over list of given type safe against removal of list entry
#define	list_for_each_entry_safe_reverse(pos, n, head, member)
	iterate backwards over list of given type safe against removal of list entry
Typedefs
typedef list_head	list_t
	list head

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Define Documentation

#define container_of	(	ptr,
		type,
		member		)	((type *)((char *)(ptr) - offsetof(type, member)))

get container of list head

Definition at line 48 of file list.h.

#define LIST_NODE_ALLOC

(

NAME

)

NAME = mem_alloc(sizeof(*NAME))

Definition at line 66 of file list.h.

#define list_entry	(	ptr,
		type,
		member		)	container_of(ptr, type, member)

get the struct for this entry

Parameters:

	ptr	the &list_t pointer
	type	the type of the struct this is embedded in
	member	the name of the list_struct within the struct

Definition at line 250 of file list.h.

Referenced by strtok_delete(), strtok_free(), strtok_next(), and strtok_prev().

#define list_for_each	(	pos,
		head		)	for (pos = (head)->next; pos != (head); pos = pos->next)

iterate over a list

Parameters:

	pos	the &list_t to use as a loop counter
	head	the head for your list

Definition at line 259 of file list.h.

Referenced by strtok_count().

#define list_for_each_prev	(	pos,
		head		)	for (pos = (head)->prev; pos != (head); pos = pos->prev)

iterate over a list backwards

Parameters:

	pos	the &list_t to use as a loop counter
	head	the head for your list

Definition at line 268 of file list.h.

#define list_for_each_safe	(	pos,
		n,
		head		)

Value:

for (pos = (head)->next, n = pos->next; pos != (head); \
                pos = n, n = pos->next)

iterate over a list safe against removal of list entry

Parameters:

	pos	the &list_t to use as a loop counter
	n	another &list_t to use as temporary storage
	head	the head for your list

Definition at line 278 of file list.h.

Referenced by strtok_delete(), and strtok_free().

#define list_for_each_entry	(	pos,
		head,
		member		)

Value:

for (pos = list_entry((head)->next, typeof(*pos), member); \
             &pos->member != (head); \
             pos = list_entry(pos->member.next, typeof(*pos), member))

iterate over list of given type

Parameters:

	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

Definition at line 289 of file list.h.

#define list_for_each_entry_reverse	(	pos,
		head,
		member		)

Value:

for (pos = list_entry((head)->prev, typeof(*pos), member); \
             &pos->member != (head); \
             pos = list_entry(pos->member.prev, typeof(*pos), member))

iterate backwards over list of given type.

Parameters:

	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

Definition at line 301 of file list.h.

#define list_for_each_entry_safe	(	pos,
		n,
		head,
		member		)

Value:

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))

iterate over list of given type safe against removal of list entry

Parameters:

	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

Definition at line 314 of file list.h.

#define list_for_each_entry_safe_reverse	(	pos,
		n,
		head,
		member		)

Value:

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))

iterate backwards over list of given type safe against removal of list entry

Parameters:

	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

Definition at line 328 of file list.h.

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Typedef Documentation

typedef struct list_head list_t

list head

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