/*
 * OSPF LSDB support.
 * Copyright (C) 1999, 2000 Alex Zinin, Kunihiro Ishiguro, Toshiaki Takada
 *
 * 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 this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <zebra.h>

#include "prefix.h"
#include "table.h"
#include "memory.h"
#include "log.h"

#include "ospfd/ospfd.h"
#include "ospfd/ospf_asbr.h"
#include "ospfd/ospf_lsa.h"
#include "ospfd/ospf_lsdb.h"

struct ospf_lsdb *ospf_lsdb_new(void)
{
	struct ospf_lsdb *new;

	new = XCALLOC(MTYPE_OSPF_LSDB, sizeof(struct ospf_lsdb));
	ospf_lsdb_init(new);

	return new;
}

void ospf_lsdb_init(struct ospf_lsdb *lsdb)
{
	int i;

	for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++)
		lsdb->type[i].db = route_table_init();
}

void ospf_lsdb_free(struct ospf_lsdb *lsdb)
{
	ospf_lsdb_cleanup(lsdb);
	XFREE(MTYPE_OSPF_LSDB, lsdb);
}

void ospf_lsdb_cleanup(struct ospf_lsdb *lsdb)
{
	int i;
	assert(lsdb);
	assert(lsdb->total == 0);

	ospf_lsdb_delete_all(lsdb);

	for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++)
		route_table_finish(lsdb->type[i].db);
}

void ls_prefix_set(struct prefix_ls *lp, struct ospf_lsa *lsa)
{
	if (lp && lsa && lsa->data) {
		lp->family = AF_UNSPEC;
		lp->prefixlen = 64;
		lp->id = lsa->data->id;
		lp->adv_router = lsa->data->adv_router;
	}
}

static void ospf_lsdb_delete_entry(struct ospf_lsdb *lsdb,
				   struct route_node *rn)
{
	struct ospf_lsa *lsa = rn->info;

	if (!lsa)
		return;

	assert(rn->table == lsdb->type[lsa->data->type].db);

	if (IS_LSA_SELF(lsa))
		lsdb->type[lsa->data->type].count_self--;
	lsdb->type[lsa->data->type].count--;
	lsdb->type[lsa->data->type].checksum -= ntohs(lsa->data->checksum);
	lsdb->total--;
	rn->info = NULL;
	route_unlock_node(rn);
#ifdef MONITOR_LSDB_CHANGE
	if (lsdb->del_lsa_hook != NULL)
		(*lsdb->del_lsa_hook)(lsa);
#endif			       /* MONITOR_LSDB_CHANGE */
	ospf_lsa_unlock(&lsa); /* lsdb */
	return;
}

/* Add new LSA to lsdb. */
void ospf_lsdb_add(struct ospf_lsdb *lsdb, struct ospf_lsa *lsa)
{
	struct route_table *table;
	struct prefix_ls lp;
	struct route_node *rn;

	table = lsdb->type[lsa->data->type].db;
	ls_prefix_set(&lp, lsa);
	rn = route_node_get(table, (struct prefix *)&lp);

	/* nothing to do? */
	if (rn->info && rn->info == lsa) {
		route_unlock_node(rn);
		return;
	}

	/* purge old entry? */
	if (rn->info)
		ospf_lsdb_delete_entry(lsdb, rn);

	if (IS_LSA_SELF(lsa))
		lsdb->type[lsa->data->type].count_self++;
	lsdb->type[lsa->data->type].count++;
	lsdb->total++;

#ifdef MONITOR_LSDB_CHANGE
	if (lsdb->new_lsa_hook != NULL)
		(*lsdb->new_lsa_hook)(lsa);
#endif /* MONITOR_LSDB_CHANGE */
	lsdb->type[lsa->data->type].checksum += ntohs(lsa->data->checksum);
	rn->info = ospf_lsa_lock(lsa); /* lsdb */
}

void ospf_lsdb_delete(struct ospf_lsdb *lsdb, struct ospf_lsa *lsa)
{
	struct route_table *table;
	struct prefix_ls lp;
	struct route_node *rn;

	if (!lsdb || !lsa)
		return;

	assert(lsa->data->type < OSPF_MAX_LSA);
	table = lsdb->type[lsa->data->type].db;
	ls_prefix_set(&lp, lsa);
	if ((rn = route_node_lookup(table, (struct prefix *)&lp))) {
		if (rn->info == lsa)
			ospf_lsdb_delete_entry(lsdb, rn);
		route_unlock_node(rn); /* route_node_lookup */
	}
}

void ospf_lsdb_delete_all(struct ospf_lsdb *lsdb)
{
	struct route_table *table;
	struct route_node *rn;
	int i;

	for (i = OSPF_MIN_LSA; i < OSPF_MAX_LSA; i++) {
		table = lsdb->type[i].db;
		for (rn = route_top(table); rn; rn = route_next(rn))
			if (rn->info != NULL)
				ospf_lsdb_delete_entry(lsdb, rn);
	}
}

struct ospf_lsa *ospf_lsdb_lookup(struct ospf_lsdb *lsdb, struct ospf_lsa *lsa)
{
	struct route_table *table;
	struct prefix_ls lp;
	struct route_node *rn;
	struct ospf_lsa *find;

	table = lsdb->type[lsa->data->type].db;
	ls_prefix_set(&lp, lsa);
	rn = route_node_lookup(table, (struct prefix *)&lp);
	if (rn) {
		find = rn->info;
		route_unlock_node(rn);
		return find;
	}
	return NULL;
}

struct ospf_lsa *ospf_lsdb_lookup_by_id(struct ospf_lsdb *lsdb, uint8_t type,
					struct in_addr id,
					struct in_addr adv_router)
{
	struct route_table *table;
	struct prefix_ls lp;
	struct route_node *rn;
	struct ospf_lsa *find;

	table = lsdb->type[type].db;

	memset(&lp, 0, sizeof(lp));
	lp.family = AF_UNSPEC;
	lp.prefixlen = 64;
	lp.id = id;
	lp.adv_router = adv_router;

	rn = route_node_lookup(table, (struct prefix *)&lp);
	if (rn) {
		find = rn->info;
		route_unlock_node(rn);
		return find;
	}
	return NULL;
}

struct ospf_lsa *ospf_lsdb_lookup_by_id_next(struct ospf_lsdb *lsdb,
					     uint8_t type, struct in_addr id,
					     struct in_addr adv_router,
					     int first)
{
	struct route_table *table;
	struct prefix_ls lp;
	struct route_node *rn;
	struct ospf_lsa *find;

	table = lsdb->type[type].db;

	memset(&lp, 0, sizeof(lp));
	lp.family = AF_UNSPEC;
	lp.prefixlen = 64;
	lp.id = id;
	lp.adv_router = adv_router;

	if (first)
		rn = route_top(table);
	else {
		if ((rn = route_node_lookup(table, (struct prefix *)&lp))
		    == NULL)
			return NULL;
		rn = route_next(rn);
	}

	for (; rn; rn = route_next(rn))
		if (rn->info)
			break;

	if (rn && rn->info) {
		find = rn->info;
		route_unlock_node(rn);
		return find;
	}
	return NULL;
}

unsigned long ospf_lsdb_count_all(struct ospf_lsdb *lsdb)
{
	return lsdb->total;
}

unsigned long ospf_lsdb_count(struct ospf_lsdb *lsdb, int type)
{
	return lsdb->type[type].count;
}

unsigned long ospf_lsdb_count_self(struct ospf_lsdb *lsdb, int type)
{
	return lsdb->type[type].count_self;
}

unsigned int ospf_lsdb_checksum(struct ospf_lsdb *lsdb, int type)
{
	return lsdb->type[type].checksum;
}

unsigned long ospf_lsdb_isempty(struct ospf_lsdb *lsdb)
{
	return (lsdb->total == 0);
}
