Initial revision
diff --git a/lib/linklist.c b/lib/linklist.c
new file mode 100644
index 0000000..5a2b696
--- /dev/null
+++ b/lib/linklist.c
@@ -0,0 +1,312 @@
+/* Generic linked list routine.
+ * Copyright (C) 1997, 2000 Kunihiro Ishiguro
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING. If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#include <zebra.h>
+
+#include "linklist.h"
+#include "memory.h"
+
+/* Allocate new list. */
+struct list *
+list_new ()
+{
+ struct list *new;
+
+ new = XMALLOC (MTYPE_LINK_LIST, sizeof (struct list));
+ memset (new, 0, sizeof (struct list));
+ return new;
+}
+
+/* Free list. */
+void
+list_free (struct list *l)
+{
+ XFREE (MTYPE_LINK_LIST, l);
+}
+
+/* Allocate new listnode. Internal use only. */
+static struct listnode *
+listnode_new ()
+{
+ struct listnode *node;
+
+ node = XMALLOC (MTYPE_LINK_NODE, sizeof (struct listnode));
+ memset (node, 0, sizeof (struct listnode));
+ return node;
+}
+
+/* Free listnode. */
+static void
+listnode_free (struct listnode *node)
+{
+ XFREE (MTYPE_LINK_NODE, node);
+}
+
+/* Add new data to the list. */
+void
+listnode_add (struct list *list, void *val)
+{
+ struct listnode *node;
+
+ node = listnode_new ();
+
+ node->prev = list->tail;
+ node->data = val;
+
+ if (list->head == NULL)
+ list->head = node;
+ else
+ list->tail->next = node;
+ list->tail = node;
+
+ list->count++;
+}
+
+/* Add new node with sort function. */
+void
+listnode_add_sort (struct list *list, void *val)
+{
+ struct listnode *n;
+ struct listnode *new;
+
+ new = listnode_new ();
+ new->data = val;
+
+ if (list->cmp)
+ {
+ for (n = list->head; n; n = n->next)
+ {
+ if ((*list->cmp) (val, n->data) < 0)
+ {
+ new->next = n;
+ new->prev = n->prev;
+
+ if (n->prev)
+ n->prev->next = new;
+ else
+ list->head = new;
+ n->prev = new;
+ list->count++;
+ return;
+ }
+ }
+ }
+
+ new->prev = list->tail;
+
+ if (list->tail)
+ list->tail->next = new;
+ else
+ list->head = new;
+
+ list->tail = new;
+ list->count++;
+}
+
+void
+listnode_add_after (struct list *list, struct listnode *pp, void *val)
+{
+ struct listnode *nn;
+
+ nn = listnode_new ();
+ nn->data = val;
+
+ if (pp == NULL)
+ {
+ if (list->head)
+ list->head->prev = nn;
+ else
+ list->tail = nn;
+
+ nn->next = list->head;
+ nn->prev = pp;
+
+ list->head = nn;
+ }
+ else
+ {
+ if (pp->next)
+ pp->next->prev = nn;
+ else
+ list->tail = nn;
+
+ nn->next = pp->next;
+ nn->prev = pp;
+
+ pp->next = nn;
+ }
+}
+
+
+/* Delete specific date pointer from the list. */
+void
+listnode_delete (struct list *list, void *val)
+{
+ struct listnode *node;
+
+ for (node = list->head; node; node = node->next)
+ {
+ if (node->data == val)
+ {
+ if (node->prev)
+ node->prev->next = node->next;
+ else
+ list->head = node->next;
+
+ if (node->next)
+ node->next->prev = node->prev;
+ else
+ list->tail = node->prev;
+
+ list->count--;
+ listnode_free (node);
+ return;
+ }
+ }
+}
+
+/* Return first node's data if it is there. */
+void *
+listnode_head (struct list *list)
+{
+ struct listnode *node;
+
+ node = list->head;
+
+ if (node)
+ return node->data;
+ return NULL;
+}
+
+/* Delete all listnode from the list. */
+void
+list_delete_all_node (struct list *list)
+{
+ struct listnode *node;
+ struct listnode *next;
+
+ for (node = list->head; node; node = next)
+ {
+ next = node->next;
+ if (list->del)
+ (*list->del) (node->data);
+ listnode_free (node);
+ }
+ list->head = list->tail = NULL;
+ list->count = 0;
+}
+
+/* Delete all listnode then free list itself. */
+void
+list_delete (struct list *list)
+{
+ struct listnode *node;
+ struct listnode *next;
+
+ for (node = list->head; node; node = next)
+ {
+ next = node->next;
+ if (list->del)
+ (*list->del) (node->data);
+ listnode_free (node);
+ }
+ list_free (list);
+}
+
+/* Lookup the node which has given data. */
+struct listnode *
+listnode_lookup (struct list *list, void *data)
+{
+ listnode node;
+
+ for (node = list->head; node; nextnode (node))
+ if (data == getdata (node))
+ return node;
+ return NULL;
+}
+
+/* Delete the node from list. For ospfd and ospf6d. */
+void
+list_delete_node (list list, listnode node)
+{
+ if (node->prev)
+ node->prev->next = node->next;
+ else
+ list->head = node->next;
+ if (node->next)
+ node->next->prev = node->prev;
+ else
+ list->tail = node->prev;
+ list->count--;
+ listnode_free (node);
+}
+
+/* ospf_spf.c */
+void
+list_add_node_prev (list list, listnode current, void *val)
+{
+ struct listnode *node;
+
+ node = listnode_new ();
+ node->next = current;
+ node->data = val;
+
+ if (current->prev == NULL)
+ list->head = node;
+ else
+ current->prev->next = node;
+
+ node->prev = current->prev;
+ current->prev = node;
+
+ list->count++;
+}
+
+/* ospf_spf.c */
+void
+list_add_node_next (list list, listnode current, void *val)
+{
+ struct listnode *node;
+
+ node = listnode_new ();
+ node->prev = current;
+ node->data = val;
+
+ if (current->next == NULL)
+ list->tail = node;
+ else
+ current->next->prev = node;
+
+ node->next = current->next;
+ current->next = node;
+
+ list->count++;
+}
+
+/* ospf_spf.c */
+void
+list_add_list (struct list *l, struct list *m)
+{
+ struct listnode *n;
+
+ for (n = listhead (m); n; nextnode (n))
+ listnode_add (l, n->data);
+}