/*      $OpenBSD: area.c,v 1.10 2015/11/22 13:09:10 claudio Exp $ */

/*
 * Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/tree.h>
#include <err.h>
#include <stdlib.h>

#include "ospf.h"
#include "ospfd.h"
#include "ospfe.h"
#include "rde.h"
#include "log.h"

struct area *
area_new(void)
{
        struct area *area = NULL;

        if ((area = calloc(1, sizeof(*area))) == NULL)
                errx(1, "area_new: calloc");

        LIST_INIT(&area->iface_list);
        LIST_INIT(&area->nbr_list);
        RB_INIT(&area->lsa_tree);
        SIMPLEQ_INIT(&area->redist_list);

        return (area);
}

int
area_del(struct area *area)
{
        struct iface    *iface = NULL;
        struct vertex   *v, *nv;
        struct rde_nbr  *n;
        struct redistribute *r;

        /* area is removed so neutralize the demotion done by the area */
        if (area->active == 0)
                ospfe_demote_area(area, 1);

        /* clean lists */
        while ((iface = LIST_FIRST(&area->iface_list)) != NULL) {
                LIST_REMOVE(iface, entry);
                if_del(iface);
        }

        while ((n = LIST_FIRST(&area->nbr_list)) != NULL)
                rde_nbr_del(n);

        for (v = RB_MIN(lsa_tree, &area->lsa_tree); v != NULL; v = nv) {
                nv = RB_NEXT(lsa_tree, &area->lsa_tree, v);
                vertex_free(v);
        }

        while ((r = SIMPLEQ_FIRST(&area->redist_list)) != NULL) {
                SIMPLEQ_REMOVE_HEAD(&area->redist_list, entry);
                free(r);
        }

        free(area);

        return (0);
}

struct area *
area_find(struct ospfd_conf *conf, struct in_addr area_id)
{
        struct area     *area;

        LIST_FOREACH(area, &conf->area_list, entry) {
                if (area->id.s_addr == area_id.s_addr) {
                        return (area);
                }
        }

        return (NULL);
}

void
area_track(struct area *area)
{
        int             old = area->active;
        struct iface    *iface;

        area->active = 0;
        LIST_FOREACH(iface, &area->iface_list, entry) {
                if (iface->state & IF_STA_DOWN)
                        continue;
                area->active = 1;
                break;
        }

        if (area->active != old) {
                ospfe_imsg_compose_rde(IMSG_AREA_CHANGE, area->id.s_addr, 0,
                    &area->active, sizeof(area->active));
                ospfe_demote_area(area, old == 0);
        }
}

int
area_border_router(struct ospfd_conf *conf)
{
        struct area     *area;
        int              active = 0;

        LIST_FOREACH(area, &conf->area_list, entry)
                if (area->active)
                        active++;

        return (active > 1);
}

u_int8_t
area_ospf_options(struct area *area)
{
        u_int8_t        opt = 0;

        if (area && !area->stub)
                opt |= OSPF_OPTION_E;

        return (opt);
}