/*
 * Copyright (C) 2003 Yasuhiro Ohara
 *
 * 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 "log.h"
#include "memory.h"
#include "prefix.h"
#include "table.h"
#include "vty.h"
#include "command.h"
#include "linklist.h"

#include "ospf6_proto.h"
#include "ospf6_lsa.h"
#include "ospf6_lsdb.h"
#include "ospf6_route.h"
#include "ospf6_top.h"
#include "ospf6_area.h"
#include "ospf6_interface.h"
#include "ospf6d.h"
#include "ospf6_zebra.h"

unsigned char conf_debug_ospf6_route = 0;

static char *
ospf6_route_table_name (struct ospf6_route_table *table)
{
  static char name[32];
  switch (table->scope_type)
    {
      case OSPF6_SCOPE_TYPE_GLOBAL:
        {
          switch (table->table_type)
            {
              case OSPF6_TABLE_TYPE_ROUTES:
                snprintf (name, sizeof (name), "global route table");
                break;
              case OSPF6_TABLE_TYPE_BORDER_ROUTERS:
                snprintf (name, sizeof (name), "global brouter table");
                break;
              case OSPF6_TABLE_TYPE_EXTERNAL_ROUTES:
                snprintf (name, sizeof (name), "global external table");
                break;
              default:
                snprintf (name, sizeof (name), "global unknown table");
                break;
            }
        }
        break;

      case OSPF6_SCOPE_TYPE_AREA:
        {
          struct ospf6_area *oa = (struct ospf6_area *) table->scope;
          switch (table->table_type)
            {
              case OSPF6_TABLE_TYPE_SPF_RESULTS:
                snprintf (name, sizeof (name),
                          "area %s spf table", oa->name);
                break;
              case OSPF6_TABLE_TYPE_ROUTES:
                snprintf (name, sizeof (name),
                          "area %s route table", oa->name);
                break;
              case OSPF6_TABLE_TYPE_PREFIX_RANGES:
                snprintf (name, sizeof (name),
                          "area %s range table", oa->name);
                break;
              case OSPF6_TABLE_TYPE_SUMMARY_PREFIXES:
                snprintf (name, sizeof (name),
                          "area %s summary prefix table", oa->name);
                break;
              case OSPF6_TABLE_TYPE_SUMMARY_ROUTERS:
                snprintf (name, sizeof (name),
                          "area %s summary router table", oa->name);
                break;
              default:
                snprintf (name, sizeof (name),
                          "area %s unknown table", oa->name);
                break;
            }
        }
        break;

      case OSPF6_SCOPE_TYPE_INTERFACE:
        {
          struct ospf6_interface *oi = (struct ospf6_interface *) table->scope;
          switch (table->table_type)
            {
              case OSPF6_TABLE_TYPE_CONNECTED_ROUTES:
                snprintf (name, sizeof (name), "interface %s connected table",
                          oi->interface->name);
                break;
              default:
                snprintf (name, sizeof (name), "interface %s unknown table",
                          oi->interface->name);
                break;
            }
        }
        break;

      default:
        {
          switch (table->table_type)
            {
              case OSPF6_TABLE_TYPE_SPF_RESULTS:
                snprintf (name, sizeof (name), "temporary spf table");
                break;
              default:
                snprintf (name, sizeof (name), "temporary unknown table");
                break;
            }
        }
        break;
    }
  return name;
}

void
ospf6_linkstate_prefix (u_int32_t adv_router, u_int32_t id,
                        struct prefix *prefix)
{
  memset (prefix, 0, sizeof (struct prefix));
  prefix->family = AF_INET6;
  prefix->prefixlen = 64;
  memcpy (&prefix->u.prefix6.s6_addr[0], &adv_router, 4);
  memcpy (&prefix->u.prefix6.s6_addr[4], &id, 4);
}

void
ospf6_linkstate_prefix2str (struct prefix *prefix, char *buf, int size)
{
  u_int32_t adv_router, id;
  char adv_router_str[16], id_str[16];
  memcpy (&adv_router, &prefix->u.prefix6.s6_addr[0], 4);
  memcpy (&id, &prefix->u.prefix6.s6_addr[4], 4);
  inet_ntop (AF_INET, &adv_router, adv_router_str, sizeof (adv_router_str));
  inet_ntop (AF_INET, &id, id_str, sizeof (id_str));
  if (ntohl (id))
    snprintf (buf, size, "%s Net-ID: %s", adv_router_str, id_str);
  else
    snprintf (buf, size, "%s", adv_router_str);
}

/* Global strings for logging */
const char *ospf6_dest_type_str[OSPF6_DEST_TYPE_MAX] =
{ "Unknown", "Router", "Network", "Discard", "Linkstate", "AddressRange", };

const char *ospf6_dest_type_substr[OSPF6_DEST_TYPE_MAX] =
{ "?", "R", "N", "D", "L", "A", };

const char *ospf6_path_type_str[OSPF6_PATH_TYPE_MAX] =
{ "Unknown", "Intra-Area", "Inter-Area", "External-1", "External-2", };

const char *ospf6_path_type_substr[OSPF6_PATH_TYPE_MAX] =
{ "??", "IA", "IE", "E1", "E2", };


struct ospf6_nexthop *
ospf6_nexthop_create (void)
{
  struct ospf6_nexthop *nh;

  nh = XCALLOC (MTYPE_OSPF6_NEXTHOP, sizeof (struct ospf6_nexthop));
  return nh;
}

void
ospf6_nexthop_delete (struct ospf6_nexthop *nh)
{
  if (nh)
    XFREE (MTYPE_OSPF6_NEXTHOP, nh);
}

void
ospf6_free_nexthops (struct list *nh_list)
{
  struct ospf6_nexthop *nh;
  struct listnode *node, *nnode;

  if (nh_list)
    {
      for (ALL_LIST_ELEMENTS (nh_list, node, nnode, nh))
	ospf6_nexthop_delete (nh);
    }
}

void
ospf6_clear_nexthops (struct list *nh_list)
{
  struct listnode *node;
  struct ospf6_nexthop *nh;

  if (nh_list)
    {
      for (ALL_LIST_ELEMENTS_RO (nh_list, node, nh))
	ospf6_nexthop_clear (nh);
    }
}

static struct ospf6_nexthop *
ospf6_route_find_nexthop (struct list *nh_list, struct ospf6_nexthop *nh_match)
{
  struct listnode *node;
  struct ospf6_nexthop *nh;

  if (nh_list && nh_match)
    {
      for (ALL_LIST_ELEMENTS_RO (nh_list, node, nh))
	{
	  if (ospf6_nexthop_is_same (nh, nh_match))
	    return (nh);
	}
    }

  return (NULL);
}

void
ospf6_copy_nexthops (struct list *dst, struct list *src)
{
  struct ospf6_nexthop *nh_new, *nh;
  struct listnode *node;

  if (dst && src)
    {
      for (ALL_LIST_ELEMENTS_RO (src, node, nh))
	{
	  if (ospf6_nexthop_is_set (nh))
	    {
	      nh_new = ospf6_nexthop_create ();
	      ospf6_nexthop_copy (nh_new, nh);
	      listnode_add (dst, nh_new);
	    }
	}
    }
}

void
ospf6_merge_nexthops (struct list *dst, struct list *src)
{
  struct listnode *node;
  struct ospf6_nexthop *nh, *nh_new;

  if (src && dst)
    {
      for (ALL_LIST_ELEMENTS_RO (src, node, nh))
	{
	  if (!ospf6_route_find_nexthop (dst, nh))
	    {
	      nh_new = ospf6_nexthop_create ();
	      ospf6_nexthop_copy (nh_new, nh);
	      listnode_add (dst, nh_new);
	    }
	}
    }
}

int
ospf6_route_cmp_nexthops (struct ospf6_route *a, struct ospf6_route *b)
{
  struct listnode *anode, *bnode;
  struct ospf6_nexthop *anh, *bnh;

  if (a && b)
    {
      if (listcount(a->nh_list) == listcount(b->nh_list))
	{
	  for (ALL_LIST_ELEMENTS_RO (a->nh_list, anode, anh))
	    {
	      for (ALL_LIST_ELEMENTS_RO (b->nh_list, bnode, bnh))
		if (!ospf6_nexthop_is_same (anh, bnh))
		  return (1);
	    }
	  return (0);
	}
      else
	return (1);
    }
  /* One of the routes doesn't exist ? */
  return (1);
}

int
ospf6_num_nexthops (struct list *nh_list)
{
  return (listcount(nh_list));
}

void
ospf6_add_nexthop (struct list *nh_list, int ifindex,
		   struct in6_addr *addr)
{
  struct ospf6_nexthop *nh;
  struct ospf6_nexthop nh_match;

  if (nh_list)
    {
      nh_match.ifindex = ifindex;
      if (addr != NULL)
	memcpy (&nh_match.address, addr, sizeof (struct in6_addr));
      else
	memset (&nh_match.address, 0, sizeof (struct in6_addr));

      if (!ospf6_route_find_nexthop (nh_list, &nh_match))
	{
	  nh = ospf6_nexthop_create();
	  ospf6_nexthop_copy (nh, &nh_match);
	  listnode_add (nh_list, nh);
	}
    }
}

void
ospf6_route_zebra_copy_nexthops (struct ospf6_route *route,
				 ifindex_t *ifindexes,
				 struct in6_addr **nexthop_addr,
				 int entries)
{
  struct ospf6_nexthop *nh;
  struct listnode *node;
  char buf[64];
  int i;

  if (route)
    {
      i = 0;
      for (ALL_LIST_ELEMENTS_RO (route->nh_list, node, nh))
	{
	  if (IS_OSPF6_DEBUG_ZEBRA (SEND))
	    {
	      const char *ifname;
	      inet_ntop (AF_INET6, &nh->address, buf, sizeof (buf));
	      ifname = ifindex2ifname (nh->ifindex, VRF_DEFAULT);
	      zlog_debug ("  nexthop: %s%%%.*s(%d)", buf, IFNAMSIZ, ifname,
			  nh->ifindex);
	    }
	  if (i < entries)
	    {
	      nexthop_addr[i] = &nh->address;
	      ifindexes[i] = nh->ifindex;
	      i++;
	    }
	  else
	    {
	      return;
	    }
	}
    }
}

int
ospf6_route_get_first_nh_index (struct ospf6_route *route)
{
  struct ospf6_nexthop *nh;

  if (route)
    {
      if ((nh = (struct ospf6_nexthop *)listhead (route->nh_list)))
	return (nh->ifindex);
    }

  return (-1);
}

struct ospf6_route *
ospf6_route_create (void)
{
  struct ospf6_route *route;
  route = XCALLOC (MTYPE_OSPF6_ROUTE, sizeof (struct ospf6_route));
  route->nh_list = list_new();
  return route;
}

void
ospf6_route_delete (struct ospf6_route *route)
{
  if (route)
    {
      ospf6_free_nexthops (route->nh_list);
      list_free (route->nh_list);
      XFREE (MTYPE_OSPF6_ROUTE, route);
    }
}

struct ospf6_route *
ospf6_route_copy (struct ospf6_route *route)
{
  struct ospf6_route *new;

  new = ospf6_route_create ();
  new->type = route->type;
  memcpy (&new->prefix, &route->prefix, sizeof (struct prefix));
  new->installed = route->installed;
  new->changed = route->changed;
  new->flag = route->flag;
  new->route_option = route->route_option;
  new->linkstate_id = route->linkstate_id;
  new->path = route->path;
  ospf6_copy_nexthops (new->nh_list, route->nh_list);
  new->rnode = NULL;
  new->prev = NULL;
  new->next = NULL;
  new->table = NULL;
  new->lock = 0;
  return new;
}

void
ospf6_route_lock (struct ospf6_route *route)
{
  route->lock++;
}

void
ospf6_route_unlock (struct ospf6_route *route)
{
  assert (route->lock > 0);
  route->lock--;
  if (route->lock == 0)
    {
      /* Can't detach from the table until here
         because ospf6_route_next () will use
         the 'route->table' pointer for logging */
      route->table = NULL;
      ospf6_route_delete (route);
    }
}

/* Route compare function. If ra is more preferred, it returns
   less than 0. If rb is more preferred returns greater than 0.
   Otherwise (neither one is preferred), returns 0 */
int
ospf6_route_cmp (struct ospf6_route *ra, struct ospf6_route *rb)
{
  assert (ospf6_route_is_same (ra, rb));
  assert (OSPF6_PATH_TYPE_NONE < ra->path.type &&
          ra->path.type < OSPF6_PATH_TYPE_MAX);
  assert (OSPF6_PATH_TYPE_NONE < rb->path.type &&
          rb->path.type < OSPF6_PATH_TYPE_MAX);

  if (ra->type != rb->type)
    return (ra->type - rb->type);

  if (ra->path.area_id != rb->path.area_id)
    return (ntohl (ra->path.area_id) - ntohl (rb->path.area_id));

  if (ra->path.type != rb->path.type)
    return (ra->path.type - rb->path.type);

  if (ra->path.type == OSPF6_PATH_TYPE_EXTERNAL2)
    {
      if (ra->path.u.cost_e2 != rb->path.u.cost_e2)
        return (ra->path.u.cost_e2 - rb->path.u.cost_e2);
    }
  else
    {
      if (ra->path.cost != rb->path.cost)
        return (ra->path.cost - rb->path.cost);
    }

  return 0;
}

struct ospf6_route *
ospf6_route_lookup (struct prefix *prefix,
                    struct ospf6_route_table *table)
{
  struct route_node *node;
  struct ospf6_route *route;

  node = route_node_lookup (table->table, prefix);
  if (node == NULL)
    return NULL;

  route = (struct ospf6_route *) node->info;
  return route;
}

struct ospf6_route *
ospf6_route_lookup_identical (struct ospf6_route *route,
                              struct ospf6_route_table *table)
{
  struct ospf6_route *target;

  for (target = ospf6_route_lookup (&route->prefix, table);
       target; target = target->next)
    {
      if (ospf6_route_is_identical (target, route))
        return target;
    }
  return NULL;
}

struct ospf6_route *
ospf6_route_lookup_bestmatch (struct prefix *prefix,
                              struct ospf6_route_table *table)
{
  struct route_node *node;
  struct ospf6_route *route;

  node = route_node_match (table->table, prefix);
  if (node == NULL)
    return NULL;
  route_unlock_node (node);

  route = (struct ospf6_route *) node->info;
  return route;
}

#ifdef DEBUG
static void
route_table_assert (struct ospf6_route_table *table)
{
  struct ospf6_route *prev, *r, *next;
  char buf[PREFIX2STR_BUFFER];
  unsigned int link_error = 0, num = 0;
  
  r = ospf6_route_head (table);
  prev = NULL;
  while (r)
    {
      if (r->prev != prev)
        link_error++;
      
      next = ospf6_route_next (r);
      
      if (r->next != next)
        link_error++;
      
      prev = r;
      r = next;
    }
  
  for (r = ospf6_route_head (table); r; r = ospf6_route_next (r))
    num++;
  
  if (link_error == 0 && num == table->count)
    return;

  zlog_err ("PANIC !!");
  zlog_err ("Something has gone wrong with ospf6_route_table[%p]", table);
  zlog_debug ("table count = %d, real number = %d", table->count, num);
  zlog_debug ("DUMP START");
  for (r = ospf6_route_head (table); r; r = ospf6_route_next (r))
    {
      prefix2str (&r->prefix, buf, sizeof (buf));
      zlog_info ("%p<-[%p]->%p : %s", r->prev, r, r->next, buf);
    }
  zlog_debug ("DUMP END");

  assert (link_error == 0 && num == table->count);
}
#define ospf6_route_table_assert(t) (route_table_assert (t))
#else
#define ospf6_route_table_assert(t) ((void) 0)
#endif /*DEBUG*/

struct ospf6_route *
ospf6_route_add (struct ospf6_route *route,
                 struct ospf6_route_table *table)
{
  struct route_node *node, *nextnode, *prevnode;
  struct ospf6_route *current = NULL;
  struct ospf6_route *prev = NULL, *old = NULL, *next = NULL;
  char buf[PREFIX2STR_BUFFER];
  struct timeval now;

  assert (route->rnode == NULL);
  assert (route->lock == 0);
  assert (route->next == NULL);
  assert (route->prev == NULL);

  if (route->type == OSPF6_DEST_TYPE_LINKSTATE)
    ospf6_linkstate_prefix2str (&route->prefix, buf, sizeof (buf));
  else
    prefix2str (&route->prefix, buf, sizeof (buf));

  if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
    zlog_debug ("%s %p: route add %p: %s", ospf6_route_table_name (table),
                (void *)table, (void *)route, buf);
  else if (IS_OSPF6_DEBUG_ROUTE (TABLE))
    zlog_debug ("%s: route add: %s", ospf6_route_table_name (table), buf);

  monotime(&now);

  node = route_node_get (table->table, &route->prefix);
  route->rnode = node;

  /* find place to insert */
  for (current = node->info; current; current = current->next)
    {
      if (! ospf6_route_is_same (current, route))
        next = current;
      else if (current->type != route->type)
        prev = current;
      else if (ospf6_route_is_same_origin (current, route))
        old = current;
      else if (ospf6_route_cmp (current, route) > 0)
        next = current;
      else
        prev = current;

      if (old || next)
        break;
    }

  if (old)
    {
      /* if route does not actually change, return unchanged */
      if (ospf6_route_is_identical (old, route))
        {
          if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
            zlog_debug ("%s %p: route add %p: needless update of %p",
                        ospf6_route_table_name (table),
                        (void *)table, (void *)route, (void *)old);
          else if (IS_OSPF6_DEBUG_ROUTE (TABLE))
            zlog_debug ("%s: route add: needless update",
                        ospf6_route_table_name (table));

          ospf6_route_delete (route);
          SET_FLAG (old->flag, OSPF6_ROUTE_ADD);
          ospf6_route_table_assert (table);

          return old;
        }

      if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
        zlog_debug ("%s %p: route add %p: update of %p",
                    ospf6_route_table_name (table),
                    (void *)table, (void *)route, (void *)old);
      else if (IS_OSPF6_DEBUG_ROUTE (TABLE))
        zlog_debug ("%s: route add: update",
                    ospf6_route_table_name (table));

      /* replace old one if exists */
      if (node->info == old)
        {
          node->info = route;
          SET_FLAG (route->flag, OSPF6_ROUTE_BEST);
        }

      if (old->prev)
        old->prev->next = route;
      route->prev = old->prev;
      if (old->next)
        old->next->prev = route;
      route->next = old->next;

      route->installed = old->installed;
      route->changed = now;
      assert (route->table == NULL);
      route->table = table;

      ospf6_route_unlock (old); /* will be deleted later */
      ospf6_route_lock (route);

      SET_FLAG (route->flag, OSPF6_ROUTE_CHANGE);
      ospf6_route_table_assert (table);

      if (table->hook_add)
        (*table->hook_add) (route);

      return route;
    }

  /* insert if previous or next node found */
  if (prev || next)
    {
      if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
        zlog_debug ("%s %p: route add %p: another path: prev %p, next %p",
                    ospf6_route_table_name (table),
                    (void *)table, (void *)route, (void *)prev, (void *)next);
      else if (IS_OSPF6_DEBUG_ROUTE (TABLE))
        zlog_debug ("%s: route add: another path found",
                    ospf6_route_table_name (table));

      if (prev == NULL)
        prev = next->prev;
      if (next == NULL)
        next = prev->next;

      if (prev)
        prev->next = route;
      route->prev = prev;
      if (next)
        next->prev = route;
      route->next = next;

      if (node->info == next)
        {
          assert (next->rnode == node);
          node->info = route;
          UNSET_FLAG (next->flag, OSPF6_ROUTE_BEST);
          SET_FLAG (route->flag, OSPF6_ROUTE_BEST);
          if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
            zlog_info ("%s %p: route add %p: replacing previous best: %p",
                       ospf6_route_table_name (table),
                       (void *)table, (void *)route, (void *)next);
        }

      route->installed = now;
      route->changed = now;
      assert (route->table == NULL);
      route->table = table;

      ospf6_route_lock (route);
      table->count++;
      ospf6_route_table_assert (table);

      SET_FLAG (route->flag, OSPF6_ROUTE_ADD);
      if (table->hook_add)
        (*table->hook_add) (route);

      return route;
    }

  /* Else, this is the brand new route regarding to the prefix */
  if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
    zlog_debug ("%s %p: route add %p: brand new route",
                ospf6_route_table_name (table), (void *)table, (void *)route);
  else if (IS_OSPF6_DEBUG_ROUTE (TABLE))
    zlog_debug ("%s: route add: brand new route",
                ospf6_route_table_name (table));

  assert (node->info == NULL);
  node->info = route;
  SET_FLAG (route->flag, OSPF6_ROUTE_BEST);
  ospf6_route_lock (route);
  route->installed = now;
  route->changed = now;
  assert (route->table == NULL);
  route->table = table;

  /* lookup real existing next route */
  nextnode = node;
  route_lock_node (nextnode);
  do {
    nextnode = route_next (nextnode);
  } while (nextnode && nextnode->info == NULL);

  /* set next link */
  if (nextnode == NULL)
    route->next = NULL;
  else
    {
      route_unlock_node (nextnode);

      next = nextnode->info;
      route->next = next;
      next->prev = route;
    }

  /* lookup real existing prev route */
  prevnode = node;
  route_lock_node (prevnode);
  do {
    prevnode = route_prev (prevnode);
  } while (prevnode && prevnode->info == NULL);

  /* set prev link */
  if (prevnode == NULL)
    route->prev = NULL;
  else
    {
      route_unlock_node (prevnode);

      prev = prevnode->info;
      while (prev->next && ospf6_route_is_same (prev, prev->next))
        prev = prev->next;
      route->prev = prev;
      prev->next = route;
    }

  table->count++;
  ospf6_route_table_assert (table);

  SET_FLAG (route->flag, OSPF6_ROUTE_ADD);
  if (table->hook_add)
    (*table->hook_add) (route);

  return route;
}

void
ospf6_route_remove (struct ospf6_route *route,
                    struct ospf6_route_table *table)
{
  struct route_node *node;
  struct ospf6_route *current;
  char buf[PREFIX2STR_BUFFER];

  if (route->type == OSPF6_DEST_TYPE_LINKSTATE)
    ospf6_linkstate_prefix2str (&route->prefix, buf, sizeof (buf));
  else
    prefix2str (&route->prefix, buf, sizeof (buf));

  if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
    zlog_debug ("%s %p: route remove %p: %s",
                ospf6_route_table_name (table),
                (void *)table, (void *)route, buf);
  else if (IS_OSPF6_DEBUG_ROUTE (TABLE))
    zlog_debug ("%s: route remove: %s", ospf6_route_table_name (table), buf);

  node = route_node_lookup (table->table, &route->prefix);
  assert (node);

  /* find the route to remove, making sure that the route pointer
     is from the route table. */
  current = node->info;
  while (current && ospf6_route_is_same (current, route))
    {
      if (current == route)
        break;
      current = current->next;
    }
  assert (current == route);

  /* adjust doubly linked list */
  if (route->prev)
    route->prev->next = route->next;
  if (route->next)
    route->next->prev = route->prev;

  if (node->info == route)
    {
      if (route->next && route->next->rnode == node)
        {
          node->info = route->next;
          SET_FLAG (route->next->flag, OSPF6_ROUTE_BEST);
        }
      else
        node->info = NULL; /* should unlock route_node here ? */
    }

  table->count--;
  ospf6_route_table_assert (table);

  SET_FLAG (route->flag, OSPF6_ROUTE_WAS_REMOVED);

  if (table->hook_remove)
    (*table->hook_remove) (route);

  ospf6_route_unlock (route);
}

struct ospf6_route *
ospf6_route_head (struct ospf6_route_table *table)
{
  struct route_node *node;
  struct ospf6_route *route;

  node = route_top (table->table);
  if (node == NULL)
    return NULL;

  /* skip to the real existing entry */
  while (node && node->info == NULL)
    node = route_next (node);
  if (node == NULL)
    return NULL;

  route_unlock_node (node);
  assert (node->info);

  route = (struct ospf6_route *) node->info;
  assert (route->prev == NULL);
  assert (route->table == table);
  ospf6_route_lock (route);

  if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
    zlog_info ("%s %p: route head: %p<-[%p]->%p",
               ospf6_route_table_name (table), (void *)table,
               (void *)route->prev, (void *)route, (void *)route->next);

  return route;
}

struct ospf6_route *
ospf6_route_next (struct ospf6_route *route)
{
  struct ospf6_route *next = route->next;

  if (IS_OSPF6_DEBUG_ROUTE (MEMORY))
    zlog_info ("%s %p: route next: %p<-[%p]->%p",
               ospf6_route_table_name (route->table), (void *)route->table,
               (void *)route->prev, (void *)route, (void *)route->next);

  ospf6_route_unlock (route);
  if (next)
    ospf6_route_lock (next);

  return next;
}

struct ospf6_route *
ospf6_route_best_next (struct ospf6_route *route)
{
  struct route_node *rnode;
  struct ospf6_route *next;

  ospf6_route_unlock (route);

  rnode = route->rnode;
  route_lock_node (rnode);
  rnode = route_next (rnode);
  while (rnode && rnode->info == NULL)
    rnode = route_next (rnode);
  if (rnode == NULL)
    return NULL;
  route_unlock_node (rnode);

  assert (rnode->info);
  next = (struct ospf6_route *) rnode->info;
  ospf6_route_lock (next);
  return next;
}

struct ospf6_route *
ospf6_route_match_head (struct prefix *prefix,
                        struct ospf6_route_table *table)
{
  struct route_node *node;
  struct ospf6_route *route;

  /* Walk down tree. */
  node = table->table->top;
  while (node && node->p.prefixlen < prefix->prefixlen &&
	 prefix_match (&node->p, prefix))
    node = node->link[prefix_bit(&prefix->u.prefix, node->p.prefixlen)];

  if (node)
    route_lock_node (node);
  while (node && node->info == NULL)
    node = route_next (node);
  if (node == NULL)
    return NULL;
  route_unlock_node (node);

  if (! prefix_match (prefix, &node->p))
    return NULL;

  route = node->info;
  ospf6_route_lock (route);
  return route;
}

struct ospf6_route *
ospf6_route_match_next (struct prefix *prefix,
                        struct ospf6_route *route)
{
  struct ospf6_route *next;

  next = ospf6_route_next (route);
  if (next && ! prefix_match (prefix, &next->prefix))
    {
      ospf6_route_unlock (next);
      next = NULL;
    }

  return next;
}

void
ospf6_route_remove_all (struct ospf6_route_table *table)
{
  struct ospf6_route *route;
  for (route = ospf6_route_head (table); route;
       route = ospf6_route_next (route))
    ospf6_route_remove (route, table);
}

struct ospf6_route_table *
ospf6_route_table_create (int s, int t)
{
  struct ospf6_route_table *new;
  new = XCALLOC (MTYPE_OSPF6_ROUTE, sizeof (struct ospf6_route_table));
  new->table = route_table_init ();
  new->scope_type = s;
  new->table_type = t;
  return new;
}

void
ospf6_route_table_delete (struct ospf6_route_table *table)
{
  ospf6_route_remove_all (table);
  route_table_finish (table->table);
  XFREE (MTYPE_OSPF6_ROUTE, table);
}


/* VTY commands */
void
ospf6_route_show (struct vty *vty, struct ospf6_route *route)
{
  int i;
  char destination[PREFIX2STR_BUFFER], nexthop[64];
  char duration[16];
  const char *ifname;
  struct timeval now, res;
  struct listnode *node;
  struct ospf6_nexthop *nh;

  monotime(&now);
  timersub (&now, &route->changed, &res);
  timerstring (&res, duration, sizeof (duration));

  /* destination */
  if (route->type == OSPF6_DEST_TYPE_LINKSTATE)
    ospf6_linkstate_prefix2str (&route->prefix, destination,
                                sizeof (destination));
  else if (route->type == OSPF6_DEST_TYPE_ROUTER)
    inet_ntop (route->prefix.family, &route->prefix.u.prefix,
               destination, sizeof (destination));
  else
    prefix2str (&route->prefix, destination, sizeof (destination));

  i = 0;
  for (ALL_LIST_ELEMENTS_RO (route->nh_list, node, nh))
    {
      /* nexthop */
      inet_ntop (AF_INET6, &nh->address, nexthop,
                 sizeof (nexthop));
      ifname = ifindex2ifname (nh->ifindex, VRF_DEFAULT);

      if (!i)
	{
	  vty_out (vty, "%c%1s %2s %-30s %-25s %6.*s %s%s",
		   (ospf6_route_is_best (route) ? '*' : ' '),
		   OSPF6_DEST_TYPE_SUBSTR (route->type),
		   OSPF6_PATH_TYPE_SUBSTR (route->path.type),
		   destination, nexthop, IFNAMSIZ, ifname, duration, VNL);
	  i++;
	}
      else
	vty_out (vty, "%c%1s %2s %-30s %-25s %6.*s %s%s",
		 ' ', "", "", "", nexthop, IFNAMSIZ, ifname, "", VNL);
    }
}

void
ospf6_route_show_detail (struct vty *vty, struct ospf6_route *route)
{
  const char *ifname;
  char destination[PREFIX2STR_BUFFER], nexthop[64];
  char area_id[16], id[16], adv_router[16], capa[16], options[16];
  struct timeval now, res;
  char duration[16];
  struct listnode *node;
  struct ospf6_nexthop *nh;

  monotime(&now);

  /* destination */
  if (route->type == OSPF6_DEST_TYPE_LINKSTATE)
    ospf6_linkstate_prefix2str (&route->prefix, destination,
                                sizeof (destination));
  else if (route->type == OSPF6_DEST_TYPE_ROUTER)
    inet_ntop (route->prefix.family, &route->prefix.u.prefix,
               destination, sizeof (destination));
  else
    prefix2str (&route->prefix, destination, sizeof (destination));
  vty_out (vty, "Destination: %s%s", destination, VNL);

  /* destination type */
  vty_out (vty, "Destination type: %s%s",
           OSPF6_DEST_TYPE_NAME (route->type),
           VNL);

  /* Time */
  timersub (&now, &route->installed, &res);
  timerstring (&res, duration, sizeof (duration));
  vty_out (vty, "Installed Time: %s ago%s", duration, VNL);

  timersub (&now, &route->changed, &res);
  timerstring (&res, duration, sizeof (duration));
  vty_out (vty, "  Changed Time: %s ago%s", duration, VNL);

  /* Debugging info */
  vty_out (vty, "Lock: %d Flags: %s%s%s%s%s", route->lock,
           (CHECK_FLAG (route->flag, OSPF6_ROUTE_BEST)   ? "B" : "-"),
           (CHECK_FLAG (route->flag, OSPF6_ROUTE_ADD)    ? "A" : "-"),
           (CHECK_FLAG (route->flag, OSPF6_ROUTE_REMOVE) ? "R" : "-"),
           (CHECK_FLAG (route->flag, OSPF6_ROUTE_CHANGE) ? "C" : "-"),
           VNL);
  vty_out (vty, "Memory: prev: %p this: %p next: %p%s",
           (void *)route->prev, (void *)route, (void *)route->next, VNL);

  /* Path section */

  /* Area-ID */
  inet_ntop (AF_INET, &route->path.area_id, area_id, sizeof (area_id));
  vty_out (vty, "Associated Area: %s%s", area_id, VNL);

  /* Path type */
  vty_out (vty, "Path Type: %s%s",
           OSPF6_PATH_TYPE_NAME (route->path.type), VNL);

  /* LS Origin */
  inet_ntop (AF_INET, &route->path.origin.id, id, sizeof (id));
  inet_ntop (AF_INET, &route->path.origin.adv_router, adv_router,
             sizeof (adv_router));
  vty_out (vty, "LS Origin: %s Id: %s Adv: %s%s",
           ospf6_lstype_name (route->path.origin.type),
           id, adv_router, VNL);

  /* Options */
  ospf6_options_printbuf (route->path.options, options, sizeof (options));
  vty_out (vty, "Options: %s%s", options, VNL);

  /* Router Bits */
  ospf6_capability_printbuf (route->path.router_bits, capa, sizeof (capa));
  vty_out (vty, "Router Bits: %s%s", capa, VNL);

  /* Prefix Options */
  vty_out (vty, "Prefix Options: xxx%s", VNL);

  /* Metrics */
  vty_out (vty, "Metric Type: %d%s", route->path.metric_type,
           VNL);
  vty_out (vty, "Metric: %d (%d)%s",
           route->path.cost, route->path.u.cost_e2, VNL);

  /* Nexthops */
  vty_out (vty, "Nexthop:%s", VNL);
  for (ALL_LIST_ELEMENTS_RO (route->nh_list, node, nh))
    {
      /* nexthop */
      inet_ntop (AF_INET6, &nh->address, nexthop, sizeof (nexthop));
      ifname = ifindex2ifname (nh->ifindex, VRF_DEFAULT);
      vty_out (vty, "  %s %.*s%s", nexthop, IFNAMSIZ, ifname, VNL);
    }
  vty_out (vty, "%s", VNL);
}

static void
ospf6_route_show_table_summary (struct vty *vty,
                                struct ospf6_route_table *table)
{
  struct ospf6_route *route, *prev = NULL;
  int i, pathtype[OSPF6_PATH_TYPE_MAX];
  unsigned int number = 0;
  int nh_count =0 , nhinval = 0, ecmp = 0;
  int alternative = 0, destination = 0;

  for (i = 0; i < OSPF6_PATH_TYPE_MAX; i++)
    pathtype[i] = 0;

  for (route = ospf6_route_head (table); route;
       route = ospf6_route_next (route))
    {
      if (prev == NULL || ! ospf6_route_is_same (prev, route))
        destination++;
      else
        alternative++;
      nh_count = ospf6_num_nexthops (route->nh_list);
      if (!nh_count)
        nhinval++;
      else if (nh_count > 1)
        ecmp++;
      pathtype[route->path.type]++;
      number++;

      prev = route;
    }

  assert (number == table->count);

  vty_out (vty, "Number of OSPFv3 routes: %d%s", number, VNL);
  vty_out (vty, "Number of Destination: %d%s", destination, VNL);
  vty_out (vty, "Number of Alternative routes: %d%s", alternative, VNL);
  vty_out (vty, "Number of Equal Cost Multi Path: %d%s", ecmp, VNL);
  for (i = OSPF6_PATH_TYPE_INTRA; i <= OSPF6_PATH_TYPE_EXTERNAL2; i++)
    {
      vty_out (vty, "Number of %s routes: %d%s",
               OSPF6_PATH_TYPE_NAME (i), pathtype[i], VNL);
    }
}

static void
ospf6_route_show_table_prefix (struct vty *vty,
                               struct prefix *prefix,
                               struct ospf6_route_table *table)
{
  struct ospf6_route *route;

  route = ospf6_route_lookup (prefix, table);
  if (route == NULL)
    return;

  ospf6_route_lock (route);
  while (route && ospf6_route_is_prefix (prefix, route))
    {
      /* Specifying a prefix will always display details */
      ospf6_route_show_detail (vty, route);
      route = ospf6_route_next (route);
    }
  if (route)
    ospf6_route_unlock (route);
}

static void
ospf6_route_show_table_address (struct vty *vty,
                                struct prefix *prefix,
                                struct ospf6_route_table *table)
{
  struct ospf6_route *route;

  route = ospf6_route_lookup_bestmatch (prefix, table);
  if (route == NULL)
    return;

  prefix = &route->prefix;
  ospf6_route_lock (route);
  while (route && ospf6_route_is_prefix (prefix, route))
    {
      /* Specifying a prefix will always display details */
      ospf6_route_show_detail (vty, route);
      route = ospf6_route_next (route);
    }
  if (route)
    ospf6_route_unlock (route);
}

static void
ospf6_route_show_table_match (struct vty *vty, int detail,
                              struct prefix *prefix,
                              struct ospf6_route_table *table)
{
  struct ospf6_route *route;
  assert (prefix->family);

  route = ospf6_route_match_head (prefix, table);
  while (route)
    {
      if (detail)
        ospf6_route_show_detail (vty, route);
      else
        ospf6_route_show (vty, route);
      route = ospf6_route_match_next (prefix, route);
    }
}

static void
ospf6_route_show_table_type (struct vty *vty, int detail, u_char type,
                             struct ospf6_route_table *table)
{
  struct ospf6_route *route;

  route = ospf6_route_head (table);
  while (route)
    {
      if (route->path.type == type)
        {
          if (detail)
            ospf6_route_show_detail (vty, route);
          else
            ospf6_route_show (vty, route);
        }
      route = ospf6_route_next (route);
    }
}

static void
ospf6_route_show_table (struct vty *vty, int detail,
                        struct ospf6_route_table *table)
{
  struct ospf6_route *route;

  route = ospf6_route_head (table);
  while (route)
    {
      if (detail)
        ospf6_route_show_detail (vty, route);
      else
        ospf6_route_show (vty, route);
      route = ospf6_route_next (route);
    }
}

int
ospf6_route_table_show (struct vty *vty, int argc_start, int argc, struct cmd_token **argv,
                        struct ospf6_route_table *table)
{
  int summary = 0;
  int match = 0;
  int detail = 0;
  int slash = 0;
  int isprefix = 0;
  int i, ret;
  struct prefix prefix;
  u_char type = 0;

  memset (&prefix, 0, sizeof (struct prefix));

  for (i = argc_start; i < argc; i++)
    {
      if (! strcmp (argv[i]->arg, "summary"))
        {
          summary++;
          continue;
        }

      if (! strcmp (argv[i]->arg, "intra-area"))
        {
          type = OSPF6_PATH_TYPE_INTRA;
          continue;
        }

      if (! strcmp (argv[i]->arg, "inter-area"))
        {
          type = OSPF6_PATH_TYPE_INTER;
          continue;
        }

      if (! strcmp (argv[i]->arg, "external-1"))
        {
          type = OSPF6_PATH_TYPE_EXTERNAL1;
          continue;
        }

      if (! strcmp (argv[i]->arg, "external-2"))
        {
          type = OSPF6_PATH_TYPE_EXTERNAL2;
          continue;
        }

      if (! strcmp (argv[i]->arg, "detail"))
        {
          detail++;
          continue;
        }

      if (! strcmp (argv[i]->arg, "match"))
        {
          match++;
          continue;
        }

      ret = str2prefix (argv[i]->arg, &prefix);
      if (ret == 1 && prefix.family == AF_INET6)
        {
          isprefix++;
          if (strchr (argv[i]->arg, '/'))
            slash++;
          continue;
        }

      vty_out (vty, "Malformed argument: %s%s", argv[i]->arg, VNL);
      return CMD_SUCCESS;
    }

  /* Give summary of this route table */
  if (summary)
    {
      ospf6_route_show_table_summary (vty, table);
      return CMD_SUCCESS;
    }

  /* Give exact prefix-match route */
  if (isprefix && ! match)
    {
      /* If exact address, give best matching route */
      if (! slash)
        ospf6_route_show_table_address (vty, &prefix, table);
      else
        ospf6_route_show_table_prefix (vty, &prefix, table);

      return CMD_SUCCESS;
    }

  if (match)
    ospf6_route_show_table_match (vty, detail, &prefix, table);
  else if (type)
    ospf6_route_show_table_type (vty, detail, type, table);
  else
    ospf6_route_show_table (vty, detail, table);

  return CMD_SUCCESS;
}

static void
ospf6_linkstate_show_header (struct vty *vty)
{
  vty_out (vty, "%-7s %-15s %-15s %-8s %-14s %s%s",
           "Type", "Router-ID", "Net-ID", "Rtr-Bits", "Options", "Cost", VNL);
}

static void
ospf6_linkstate_show (struct vty *vty, struct ospf6_route *route)
{
  u_int32_t router, id;
  char routername[16], idname[16], rbits[16], options[16];

  router = ospf6_linkstate_prefix_adv_router (&route->prefix);
  inet_ntop (AF_INET, &router, routername, sizeof (routername));
  id = ospf6_linkstate_prefix_id (&route->prefix);
  inet_ntop (AF_INET, &id, idname, sizeof (idname));

  ospf6_capability_printbuf (route->path.router_bits, rbits, sizeof (rbits));
  ospf6_options_printbuf (route->path.options, options, sizeof (options));

  if (ntohl (id))
    vty_out (vty, "%-7s %-15s %-15s %-8s %-14s %lu%s",
             "Network", routername, idname, rbits, options,
             (unsigned long) route->path.cost, VNL);
  else
    vty_out (vty, "%-7s %-15s %-15s %-8s %-14s %lu%s",
             "Router", routername, idname, rbits, options,
             (unsigned long) route->path.cost, VNL);
}


static void
ospf6_linkstate_show_table_exact (struct vty *vty,
                                  struct prefix *prefix,
                                  struct ospf6_route_table *table)
{
  struct ospf6_route *route;

  route = ospf6_route_lookup (prefix, table);
  if (route == NULL)
    return;

  ospf6_route_lock (route);
  while (route && ospf6_route_is_prefix (prefix, route))
    {
      /* Specifying a prefix will always display details */
      ospf6_route_show_detail (vty, route);
      route = ospf6_route_next (route);
    }
  if (route)
    ospf6_route_unlock (route);
}

static void
ospf6_linkstate_show_table (struct vty *vty, int detail,
                            struct ospf6_route_table *table)
{
  struct ospf6_route *route;

  if (! detail)
    ospf6_linkstate_show_header (vty);

  route = ospf6_route_head (table);
  while (route)
    {
      if (detail)
        ospf6_route_show_detail (vty, route);
      else
        ospf6_linkstate_show (vty, route);
      route = ospf6_route_next (route);
    }
}

int
ospf6_linkstate_table_show (struct vty *vty, int idx_ipv4, int argc,
                            struct cmd_token **argv,
                            struct ospf6_route_table *table)
{
  int detail = 0;
  int is_id = 0;
  int is_router = 0;
  int i, ret;
  struct prefix router, id, prefix;

  memset (&router, 0, sizeof (struct prefix));
  memset (&id, 0, sizeof (struct prefix));
  memset (&prefix, 0, sizeof (struct prefix));

  for (i = idx_ipv4; i < argc; i++)
    {
      if (! strcmp (argv[i]->arg, "detail"))
        {
          detail++;
          continue;
        }

      if (! is_router)
        {
          ret = str2prefix (argv[i]->arg, &router);
          if (ret == 1 && router.family == AF_INET)
            {
              is_router++;
              continue;
            }
          vty_out (vty, "Malformed argument: %s%s", argv[i]->arg, VNL);
          return CMD_SUCCESS;
        }

      if (! is_id)
        {
          ret = str2prefix (argv[i]->arg, &id);
          if (ret == 1 && id.family == AF_INET)
            {
              is_id++;
              continue;
            }
          vty_out (vty, "Malformed argument: %s%s", argv[i]->arg, VNL);
          return CMD_SUCCESS;
        }

      vty_out (vty, "Malformed argument: %s%s", argv[i]->arg, VNL);
      return CMD_SUCCESS;
    }

  if (is_router)
    ospf6_linkstate_prefix (router.u.prefix4.s_addr,
                            id.u.prefix4.s_addr, &prefix);

  if (prefix.family)
    ospf6_linkstate_show_table_exact (vty, &prefix, table);
  else
    ospf6_linkstate_show_table (vty, detail, table);

  return CMD_SUCCESS;
}


void
ospf6_brouter_show_header (struct vty *vty)
{
  vty_out (vty, "%-15s %-8s %-14s %-10s %-15s%s",
           "Router-ID", "Rtr-Bits", "Options", "Path-Type", "Area", VNL);
}

void
ospf6_brouter_show (struct vty *vty, struct ospf6_route *route)
{
  u_int32_t adv_router;
  char adv[16], rbits[16], options[16], area[16];

  adv_router = ospf6_linkstate_prefix_adv_router (&route->prefix);
  inet_ntop (AF_INET, &adv_router, adv, sizeof (adv));
  ospf6_capability_printbuf (route->path.router_bits, rbits, sizeof (rbits));
  ospf6_options_printbuf (route->path.options, options, sizeof (options));
  inet_ntop (AF_INET, &route->path.area_id, area, sizeof (area));

  /* vty_out (vty, "%-15s %-8s %-14s %-10s %-15s%s",
           "Router-ID", "Rtr-Bits", "Options", "Path-Type", "Area", VNL); */
  vty_out (vty, "%-15s %-8s %-14s %-10s %-15s%s",
           adv, rbits, options, OSPF6_PATH_TYPE_NAME (route->path.type),
           area, VNL);
}

DEFUN (debug_ospf6_route,
       debug_ospf6_route_cmd,
       "debug ospf6 route <table|intra-area|inter-area|memory>",
       DEBUG_STR
       OSPF6_STR
       "Debug routes\n"
       "Debug route table calculation\n"
       "Debug intra-area route calculation\n"
       "Debug inter-area route calculation\n"
       "Debug route memory use\n"
       )
{
  int idx_type = 3;
  unsigned char level = 0;

  if (! strncmp (argv[idx_type]->arg, "table", 5))
    level = OSPF6_DEBUG_ROUTE_TABLE;
  else if (! strncmp (argv[idx_type]->arg, "intra", 5))
    level = OSPF6_DEBUG_ROUTE_INTRA;
  else if (! strncmp (argv[idx_type]->arg, "inter", 5))
    level = OSPF6_DEBUG_ROUTE_INTER;
  else if (! strncmp (argv[idx_type]->arg, "memor", 5))
    level = OSPF6_DEBUG_ROUTE_MEMORY;
  OSPF6_DEBUG_ROUTE_ON (level);
  return CMD_SUCCESS;
}

DEFUN (no_debug_ospf6_route,
       no_debug_ospf6_route_cmd,
       "no debug ospf6 route <table|intra-area|inter-area|memory>",
       NO_STR
       DEBUG_STR
       OSPF6_STR
       "Debug routes\n"
       "Debug route table calculation\n"
       "Debug intra-area route calculation\n"
       "Debug inter-area route calculation\n"
       "Debug route memory use\n")
{
  int idx_type = 4;
  unsigned char level = 0;

  if (! strncmp (argv[idx_type]->arg, "table", 5))
    level = OSPF6_DEBUG_ROUTE_TABLE;
  else if (! strncmp (argv[idx_type]->arg, "intra", 5))
    level = OSPF6_DEBUG_ROUTE_INTRA;
  else if (! strncmp (argv[idx_type]->arg, "inter", 5))
    level = OSPF6_DEBUG_ROUTE_INTER;
  else if (! strncmp (argv[idx_type]->arg, "memor", 5))
    level = OSPF6_DEBUG_ROUTE_MEMORY;
  OSPF6_DEBUG_ROUTE_OFF (level);
  return CMD_SUCCESS;
}

int
config_write_ospf6_debug_route (struct vty *vty)
{
  if (IS_OSPF6_DEBUG_ROUTE (TABLE))
    vty_out (vty, "debug ospf6 route table%s", VNL);
  if (IS_OSPF6_DEBUG_ROUTE (INTRA))
    vty_out (vty, "debug ospf6 route intra-area%s", VNL);
  if (IS_OSPF6_DEBUG_ROUTE (INTER))
    vty_out (vty, "debug ospf6 route inter-area%s", VNL);
  return 0;
}

void
install_element_ospf6_debug_route (void)
{
  install_element (ENABLE_NODE, &debug_ospf6_route_cmd);
  install_element (ENABLE_NODE, &no_debug_ospf6_route_cmd);
  install_element (CONFIG_NODE, &debug_ospf6_route_cmd);
  install_element (CONFIG_NODE, &no_debug_ospf6_route_cmd);
}