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-rw-r--r--lib/lists.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/lib/lists.c b/lib/lists.c
index c14eb4c7..6d97ff50 100644
--- a/lib/lists.c
+++ b/lib/lists.c
@@ -6,11 +6,36 @@
* Can be freely distributed and used under the terms of the GNU GPL.
*/
+/**
+ * DOC: Linked lists
+ *
+ * The BIRD library provides a set of functions for operating on linked
+ * lists. The lists are internally represented as standard doubly linked
+ * lists with synthetic head and tail which makes all the basic operations
+ * run in constant time and contain no extra end-of-list checks. Each list
+ * is described by a &list structure, nodes can have any format as long
+ * as they start with a &node structure. If you want your nodes to belong
+ * to multiple lists at once, you can embed multiple &node structures in them
+ * and use the SKIP_BACK() macro to calculate a pointer to the start of the
+ * structure from a &node pointer, but beware of obscurity.
+ *
+ * There also exist safe linked lists (&slist, &snode and all functions
+ * being prefixed with |s_|) which support asynchronous walking very
+ * similar to that used in the &fib structure.
+ */
+
#define _BIRD_LISTS_C_
#include "nest/bird.h"
#include "lib/lists.h"
+/**
+ * add_tail - append a node to a list
+ * @l: linked list
+ * @n: list node
+ *
+ * add_tail() takes a node @n and appends it at the end of the list @l.
+ */
LIST_INLINE void
add_tail(list *l, node *n)
{
@@ -22,6 +47,13 @@ add_tail(list *l, node *n)
l->tail = n;
}
+/**
+ * add_head - prepend a node to a list
+ * @l: linked list
+ * @n: list node
+ *
+ * add_head() takes a node @n and prepends it at the start of the list @l.
+ */
LIST_INLINE void
add_head(list *l, node *n)
{
@@ -33,6 +65,14 @@ add_head(list *l, node *n)
l->head = n;
}
+/**
+ * insert_node - insert a node to a list
+ * @n: a new list node
+ * @after: a node of a list
+ *
+ * Inserts a node @n to a linked list after an already inserted
+ * node @after.
+ */
LIST_INLINE void
insert_node(node *n, node *after)
{
@@ -44,6 +84,12 @@ insert_node(node *n, node *after)
z->prev = n;
}
+/**
+ * rem_node - remove a node from a list
+ * @n: node to be removed
+ *
+ * Removes a node @n from the list it's linked in.
+ */
LIST_INLINE void
rem_node(node *n)
{
@@ -54,6 +100,13 @@ rem_node(node *n)
x->prev = z;
}
+/**
+ * init_list - create an empty list
+ * @l: list
+ *
+ * init_list() takes a &list structure and initializes its
+ * fields, so that it represents an empty list.
+ */
LIST_INLINE void
init_list(list *l)
{
@@ -62,6 +115,14 @@ init_list(list *l)
l->tail = (node *) &l->head;
}
+/**
+ * add_tail_list - concatenate two lists
+ * @to: destination list
+ * @l: source list
+ *
+ * This function appends all elements of the list @l to
+ * the list @to in constant time.
+ */
LIST_INLINE void
add_tail_list(list *to, list *l)
{