Initial revision
diff --git a/lib/table.c b/lib/table.c
new file mode 100644
index 0000000..00ba58d
--- /dev/null
+++ b/lib/table.c
@@ -0,0 +1,503 @@
+/*
+ * Routing Table functions.
+ * Copyright (C) 1998 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 "prefix.h"
+#include "table.h"
+#include "memory.h"
+#include "sockunion.h"
+
+void route_node_delete (struct route_node *);
+void route_table_free (struct route_table *);
+
+struct route_table *
+route_table_init (void)
+{
+ struct route_table *rt;
+
+ rt = XCALLOC (MTYPE_ROUTE_TABLE, sizeof (struct route_table));
+ return rt;
+}
+
+void
+route_table_finish (struct route_table *rt)
+{
+ route_table_free (rt);
+}
+
+/* Allocate new route node. */
+struct route_node *
+route_node_new ()
+{
+ struct route_node *node;
+ node = XCALLOC (MTYPE_ROUTE_NODE, sizeof (struct route_node));
+ return node;
+}
+
+/* Allocate new route node with prefix set. */
+struct route_node *
+route_node_set (struct route_table *table, struct prefix *prefix)
+{
+ struct route_node *node;
+
+ node = route_node_new ();
+
+ prefix_copy (&node->p, prefix);
+ node->table = table;
+
+ return node;
+}
+
+/* Free route node. */
+void
+route_node_free (struct route_node *node)
+{
+ XFREE (MTYPE_ROUTE_NODE, node);
+}
+
+/* Free route table. */
+void
+route_table_free (struct route_table *rt)
+{
+ struct route_node *tmp_node;
+ struct route_node *node;
+
+ if (rt == NULL)
+ return;
+
+ node = rt->top;
+
+ while (node)
+ {
+ if (node->l_left)
+ {
+ node = node->l_left;
+ continue;
+ }
+
+ if (node->l_right)
+ {
+ node = node->l_right;
+ continue;
+ }
+
+ tmp_node = node;
+ node = node->parent;
+
+ if (node != NULL)
+ {
+ if (node->l_left == tmp_node)
+ node->l_left = NULL;
+ else
+ node->l_right = NULL;
+
+ route_node_free (tmp_node);
+ }
+ else
+ {
+ route_node_free (tmp_node);
+ break;
+ }
+ }
+
+ XFREE (MTYPE_ROUTE_TABLE, rt);
+ return;
+}
+
+/* Utility mask array. */
+static u_char maskbit[] =
+{
+ 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff
+};
+
+/* Common prefix route genaration. */
+static void
+route_common (struct prefix *n, struct prefix *p, struct prefix *new)
+{
+ int i;
+ u_char diff;
+ u_char mask;
+
+ u_char *np = (u_char *)&n->u.prefix;
+ u_char *pp = (u_char *)&p->u.prefix;
+ u_char *newp = (u_char *)&new->u.prefix;
+
+ for (i = 0; i < p->prefixlen / 8; i++)
+ {
+ if (np[i] == pp[i])
+ newp[i] = np[i];
+ else
+ break;
+ }
+
+ new->prefixlen = i * 8;
+
+ if (new->prefixlen != p->prefixlen)
+ {
+ diff = np[i] ^ pp[i];
+ mask = 0x80;
+ while (new->prefixlen < p->prefixlen && !(mask & diff))
+ {
+ mask >>= 1;
+ new->prefixlen++;
+ }
+ newp[i] = np[i] & maskbit[new->prefixlen % 8];
+ }
+}
+
+/* Macro version of check_bit (). */
+#define CHECK_BIT(X,P) ((((u_char *)(X))[(P) / 8]) >> (7 - ((P) % 8)) & 1)
+
+/* Check bit of the prefix. */
+static int
+check_bit (u_char *prefix, u_char prefixlen)
+{
+ int offset;
+ int shift;
+ u_char *p = (u_char *)prefix;
+
+ assert (prefixlen <= 128);
+
+ offset = prefixlen / 8;
+ shift = 7 - (prefixlen % 8);
+
+ return (p[offset] >> shift & 1);
+}
+
+/* Macro version of set_link (). */
+#define SET_LINK(X,Y) (X)->link[CHECK_BIT(&(Y)->prefix,(X)->prefixlen)] = (Y);\
+ (Y)->parent = (X)
+
+static void
+set_link (struct route_node *node, struct route_node *new)
+{
+ int bit;
+
+ bit = check_bit (&new->p.u.prefix, node->p.prefixlen);
+
+ assert (bit == 0 || bit == 1);
+
+ node->link[bit] = new;
+ new->parent = node;
+}
+
+/* Lock node. */
+struct route_node *
+route_lock_node (struct route_node *node)
+{
+ node->lock++;
+ return node;
+}
+
+/* Unlock node. */
+void
+route_unlock_node (struct route_node *node)
+{
+ node->lock--;
+
+ if (node->lock == 0)
+ route_node_delete (node);
+}
+
+/* Dump routing table. */
+void
+route_dump_node (struct route_table *t)
+{
+ struct route_node *node;
+ char buf[46];
+
+ for (node = route_top (t); node != NULL; node = route_next (node))
+ {
+ printf ("[%d] %p %s/%d\n",
+ node->lock,
+ node->info,
+ inet_ntop (node->p.family, &node->p.u.prefix, buf, 46),
+ node->p.prefixlen);
+ }
+}
+
+/* Find matched prefix. */
+struct route_node *
+route_node_match (struct route_table *table, struct prefix *p)
+{
+ struct route_node *node;
+ struct route_node *matched;
+
+ matched = NULL;
+ node = table->top;
+
+ /* Walk down tree. If there is matched route then store it to
+ matched. */
+ while (node && node->p.prefixlen <= p->prefixlen &&
+ prefix_match (&node->p, p))
+ {
+ if (node->info)
+ matched = node;
+ node = node->link[check_bit(&p->u.prefix, node->p.prefixlen)];
+ }
+
+ /* If matched route found, return it. */
+ if (matched)
+ return route_lock_node (matched);
+
+ return NULL;
+}
+
+struct route_node *
+route_node_match_ipv4 (struct route_table *table, struct in_addr *addr)
+{
+ struct prefix_ipv4 p;
+
+ memset (&p, 0, sizeof (struct prefix_ipv4));
+ p.family = AF_INET;
+ p.prefixlen = IPV4_MAX_PREFIXLEN;
+ p.prefix = *addr;
+
+ return route_node_match (table, (struct prefix *) &p);
+}
+
+#ifdef HAVE_IPV6
+struct route_node *
+route_node_match_ipv6 (struct route_table *table, struct in6_addr *addr)
+{
+ struct prefix_ipv6 p;
+
+ memset (&p, 0, sizeof (struct prefix_ipv6));
+ p.family = AF_INET6;
+ p.prefixlen = IPV6_MAX_PREFIXLEN;
+ p.prefix = *addr;
+
+ return route_node_match (table, (struct prefix *) &p);
+}
+#endif /* HAVE_IPV6 */
+
+/* Lookup same prefix node. Return NULL when we can't find route. */
+struct route_node *
+route_node_lookup (struct route_table *table, struct prefix *p)
+{
+ struct route_node *node;
+
+ node = table->top;
+
+ while (node && node->p.prefixlen <= p->prefixlen &&
+ prefix_match (&node->p, p))
+ {
+ if (node->p.prefixlen == p->prefixlen && node->info)
+ return route_lock_node (node);
+
+ node = node->link[check_bit(&p->u.prefix, node->p.prefixlen)];
+ }
+
+ return NULL;
+}
+
+/* Add node to routing table. */
+struct route_node *
+route_node_get (struct route_table *table, struct prefix *p)
+{
+ struct route_node *new;
+ struct route_node *node;
+ struct route_node *match;
+
+ match = NULL;
+ node = table->top;
+ while (node && node->p.prefixlen <= p->prefixlen &&
+ prefix_match (&node->p, p))
+ {
+ if (node->p.prefixlen == p->prefixlen)
+ {
+ route_lock_node (node);
+ return node;
+ }
+ match = node;
+ node = node->link[check_bit(&p->u.prefix, node->p.prefixlen)];
+ }
+
+ if (node == NULL)
+ {
+ new = route_node_set (table, p);
+ if (match)
+ set_link (match, new);
+ else
+ table->top = new;
+ }
+ else
+ {
+ new = route_node_new ();
+ route_common (&node->p, p, &new->p);
+ new->p.family = p->family;
+ new->table = table;
+ set_link (new, node);
+
+ if (match)
+ set_link (match, new);
+ else
+ table->top = new;
+
+ if (new->p.prefixlen != p->prefixlen)
+ {
+ match = new;
+ new = route_node_set (table, p);
+ set_link (match, new);
+ }
+ }
+ route_lock_node (new);
+
+ return new;
+}
+
+/* Delete node from the routing table. */
+void
+route_node_delete (struct route_node *node)
+{
+ struct route_node *child;
+ struct route_node *parent;
+
+ assert (node->lock == 0);
+ assert (node->info == NULL);
+
+ if (node->l_left && node->l_right)
+ return;
+
+ if (node->l_left)
+ child = node->l_left;
+ else
+ child = node->l_right;
+
+ parent = node->parent;
+
+ if (child)
+ child->parent = parent;
+
+ if (parent)
+ {
+ if (parent->l_left == node)
+ parent->l_left = child;
+ else
+ parent->l_right = child;
+ }
+ else
+ node->table->top = child;
+
+ route_node_free (node);
+
+ /* If parent node is stub then delete it also. */
+ if (parent && parent->lock == 0)
+ route_node_delete (parent);
+}
+
+/* Get fist node and lock it. This function is useful when one want
+ to lookup all the node exist in the routing table. */
+struct route_node *
+route_top (struct route_table *table)
+{
+ /* If there is no node in the routing table return NULL. */
+ if (table->top == NULL)
+ return NULL;
+
+ /* Lock the top node and return it. */
+ route_lock_node (table->top);
+ return table->top;
+}
+
+/* Unlock current node and lock next node then return it. */
+struct route_node *
+route_next (struct route_node *node)
+{
+ struct route_node *next;
+ struct route_node *start;
+
+ /* Node may be deleted from route_unlock_node so we have to preserve
+ next node's pointer. */
+
+ if (node->l_left)
+ {
+ next = node->l_left;
+ route_lock_node (next);
+ route_unlock_node (node);
+ return next;
+ }
+ if (node->l_right)
+ {
+ next = node->l_right;
+ route_lock_node (next);
+ route_unlock_node (node);
+ return next;
+ }
+
+ start = node;
+ while (node->parent)
+ {
+ if (node->parent->l_left == node && node->parent->l_right)
+ {
+ next = node->parent->l_right;
+ route_lock_node (next);
+ route_unlock_node (start);
+ return next;
+ }
+ node = node->parent;
+ }
+ route_unlock_node (start);
+ return NULL;
+}
+
+/* Unlock current node and lock next node until limit. */
+struct route_node *
+route_next_until (struct route_node *node, struct route_node *limit)
+{
+ struct route_node *next;
+ struct route_node *start;
+
+ /* Node may be deleted from route_unlock_node so we have to preserve
+ next node's pointer. */
+
+ if (node->l_left)
+ {
+ next = node->l_left;
+ route_lock_node (next);
+ route_unlock_node (node);
+ return next;
+ }
+ if (node->l_right)
+ {
+ next = node->l_right;
+ route_lock_node (next);
+ route_unlock_node (node);
+ return next;
+ }
+
+ start = node;
+ while (node->parent && node != limit)
+ {
+ if (node->parent->l_left == node && node->parent->l_right)
+ {
+ next = node->parent->l_right;
+ route_lock_node (next);
+ route_unlock_node (start);
+ return next;
+ }
+ node = node->parent;
+ }
+ route_unlock_node (start);
+ return NULL;
+}