/*
* The olsr.org Optimized Link-State Routing daemon(olsrd)
* Copyright (c) 2004, Thomas Lopatic (thomas@lopatic.de)
* IPv4 performance optimization (c) 2006, sven-ola(gmx.de)
* SPF implementation (c) 2007, Hannes Gredler (hannes@gredler.at)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of olsr.org, olsrd nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Visit http://www.olsr.org for more information.
*
* If you find this software useful feel free to make a donation
* to the project. For more information see the website or contact
* the copyright holders.
*
* $Id: lq_route.c,v 1.53 2007/10/16 09:54:43 bernd67 Exp $
*/
#include "defs.h"
#include "olsr.h"
#include "tc_set.h"
#include "neighbor_table.h"
#include "two_hop_neighbor_table.h"
#include "link_set.h"
#include "routing_table.h"
#include "mid_set.h"
#include "hna_set.h"
#include "lq_list.h"
#include "lq_avl.h"
#include "lq_route.h"
/*
* avl_comp_etx
*
* compare two etx metrics.
* return 0 if there is an exact match and
* -1 / +1 depending on being smaller or bigger.
* note that this results in the most optimal code
* after compiler optimization.
*/
static int
avl_comp_etx (void *etx1, void *etx2)
{
if (*(float *)etx1 < *(float *)etx2) {
return -1;
}
if (*(float *)etx1 > *(float *)etx2) {
return +1;
}
return 0;
}
/*
* olsr_spf_add_cand_tree
*
* Key an existing vertex to a candidate tree.
*/
static void
olsr_spf_add_cand_tree (struct avl_tree *tree,
struct tc_entry *vert)
{
vert->cand_tree_node.key = &vert->path_etx;
vert->cand_tree_node.data = vert;
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: insert candidate %s, cost %f\n",
olsr_ip_to_string(&(vert->addr)),
vert->path_etx);
#endif
avl_insert(tree, &vert->cand_tree_node, AVL_DUP);
}
/*
* olsr_spf_del_cand_tree
*
* Unkey an existing vertex from a candidate tree.
*/
static void
olsr_spf_del_cand_tree (struct avl_tree *tree,
struct tc_entry *vert)
{
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: delete candidate %s, cost %f\n",
olsr_ip_to_string(&(vert->addr)),
vert->path_etx);
#endif
avl_delete(tree, &vert->cand_tree_node);
}
/*
* olsr_spf_add_path_list
*
* Insert an SPF result at the end of the path list.
*/
static void
olsr_spf_add_path_list (struct list_node *head,
int *path_count,
struct tc_entry *vert)
{
vert->path_list_node.data = vert;
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: append path %s, cost %f, via %s\n",
olsr_ip_to_string(&(vert->addr)),
vert->path_etx,
olsr_ip_to_string(vert->next_hop ? &vert->next_hop->neighbor_iface_addr : NULL));
#endif
list_add_before(head, &vert->path_list_node);
*path_count = *path_count + 1;
}
/*
* olsr_spf_extract_best
*
* return the node with the minimum pathcost.
*/
static struct tc_entry *
olsr_spf_extract_best (struct avl_tree *tree)
{
struct avl_node *node;
node = avl_walk_first(tree);
return (node ? node->data : NULL);
}
char *olsr_etx_to_string(float etx)
{
static char buff[20];
if (etx == INFINITE_ETX)
return "INF";
snprintf(buff, 20, "%.6f", etx);
return buff;
}
/*
* olsr_spf_relax
*
* Explore all edges of a node and add the node
* to the candidate tree if the if the aggregate
* path cost is better.
*/
static void
olsr_spf_relax (struct avl_tree *cand_tree, struct tc_entry *vert)
{
struct tc_entry *new_vert;
struct tc_edge_entry *tc_edge;
struct avl_node *edge_node;
float new_etx;
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: exploring node %s, cost %f\n",
olsr_ip_to_string(&(vert->addr)),
vert->path_etx);
#endif
/*
* loop through all edges of this vertex.
*/
for (edge_node = avl_walk_first(&vert->edge_tree);
edge_node;
edge_node = avl_walk_next(edge_node)) {
tc_edge = edge_node->data;
/*
* We are not interested in dead-end or dying edges.
*/
if (!tc_edge->edge_inv || (tc_edge->flags & OLSR_TC_EDGE_DOWN)) {
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: ignoring edge %s\n",
olsr_ip_to_string(&tc_edge->T_dest_addr));
if (tc_edge->flags & OLSR_TC_EDGE_DOWN) {
OLSR_PRINTF(1, "SPF: edge down\n");
}
if (!tc_edge->edge_inv) {
OLSR_PRINTF(1, "SPF: no inverse edge\n");
}
#endif
continue;
}
/*
* total quality of the path through this vertex
* to the destination of this edge
*/
new_etx = vert->path_etx + tc_edge->etx;
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: exploring edge %s, cost %s\n",
olsr_ip_to_string(&(tc_edge->T_dest_addr)),
olsr_etx_to_string(new_vert->path_etx));
#endif
/*
* if it's better than the current path quality of this edge's
* destination node, then we've found a better path to this node.
*/
new_vert = tc_edge->edge_inv->tc;
if (new_etx < new_vert->path_etx) {
/* if this node has been on the candidate tree delete it */
if (new_vert->path_etx != INFINITE_ETX) {
olsr_spf_del_cand_tree(cand_tree, new_vert);
}
/* re-insert on candidate tree with the better metric */
new_vert->path_etx = new_etx;
olsr_spf_add_cand_tree(cand_tree, new_vert);
/* pull-up the next-hop and bump the hop count */
if (vert->next_hop) {
new_vert->next_hop = vert->next_hop;
}
new_vert->hops = vert->hops + 1;
#ifdef DEBUG
OLSR_PRINTF(1, "SPF: better path to %s, cost %s -> %s, via %s, hops %u\n",
olsr_ip_to_string(&new_vert->addr),
olsr_etx_to_string(new_vert->path_etx),
olsr_etx_to_string(new_etx),
olsr_ip_to_string(vert->next_hop ?
&vert->next_hop->neighbor_iface_addr : NULL),
new_vert->->hops);
#endif
}
}
}
/*
* olsr_spf_run_full
*
* Run the Dijkstra algorithm.
*
* A node gets added to the candidate tree when one of its edges has
* an overall better root path cost than the node itself.
* The node with the shortest metric gets moved from the candidate to
* the path list every pass.
* The SPF computation is completed when there are no more nodes
* on the candidate tree.
*/
static void
olsr_spf_run_full (struct avl_tree *cand_tree, struct list_node *path_list,
int *path_count)
{
struct tc_entry *vert;
*path_count = 0;
while ((vert = olsr_spf_extract_best(cand_tree))) {
olsr_spf_relax(cand_tree, vert);
/*
* move the best path from the candidate tree
* to the path list.
*/
olsr_spf_del_cand_tree(cand_tree, vert);
olsr_spf_add_path_list(path_list, path_count, vert);
}
}
void
olsr_calculate_routing_table (void)
{
struct avl_tree cand_tree;
struct list_node path_list;
int i, plen, path_count = 0;
struct tc_entry *tc;
struct tc_edge_entry *tc_edge;
struct tc_entry *vert;
struct neighbor_entry *neigh;
struct mid_address *mid_walker;
struct hna_entry *hna_gw;
struct hna_net *hna;
struct interface *inter;
struct link_entry *link;
#ifdef SPF_PROFILING
struct timeval t1, t2, t3, t4, t5, spf_init, spf_run, route, kernel, total;
gettimeofday(&t1, NULL);
#endif
/*
* Prepare the candidate tree and result list.
*/
avl_init(&cand_tree, avl_comp_etx);
list_head_init(&path_list);
olsr_bump_routingtree_version();
/*
* Initialize vertices in the lsdb.
*/
OLSR_FOR_ALL_TC_ENTRIES(tc) {
tc->next_hop = NULL;
tc->path_etx = INFINITE_ETX;
tc->hops = 0;
} OLSR_FOR_ALL_TC_ENTRIES_END(tc);
/*
* zero ourselves and add us to the candidate tree.
*/
olsr_change_myself_tc();
tc_myself->path_etx = ZERO_ETX;
olsr_spf_add_cand_tree(&cand_tree, tc_myself);
/*
* add edges to and from our neighbours.
*/
for (i = 0; i < HASHSIZE; i++)
for (neigh = neighbortable[i].next; neigh != &neighbortable[i];
neigh = neigh->next) {
if (neigh->status == SYM) {
tc_edge = olsr_lookup_tc_edge(tc_myself, &neigh->neighbor_main_addr);
link = get_best_link_to_neighbor(&neigh->neighbor_main_addr);
if (!link) {
/*
* If there is no best link to this neighbor
* and we had an edge before then flush the edge.
*/
if (tc_edge) {
olsr_delete_tc_edge_entry(tc_edge);
}
continue;
}
/*
* Set the next-hops of our neighbors.
*/
if (!tc_edge) {
tc_edge = olsr_add_tc_edge_entry(tc_myself, &neigh->neighbor_main_addr,
0, link->last_htime,
link->loss_link_quality2,
link->neigh_link_quality2);
} else {
tc_edge->link_quality = link->loss_link_quality2;
tc_edge->inverse_link_quality = link->neigh_link_quality2;
olsr_calc_tc_edge_entry_etx(tc_edge);
}
if (tc_edge->edge_inv) {
tc_edge->edge_inv->tc->next_hop = link;
}
}
}
#ifdef SPF_PROFILING
gettimeofday(&t2, NULL);
#endif
/*
* Run the SPF calculation.
*/
olsr_spf_run_full(&cand_tree, &path_list, &path_count);
OLSR_PRINTF(2, "\n--- %02d:%02d:%02d.%02d ------------------------------------------------- DIJKSTRA\n\n",
nowtm->tm_hour,
nowtm->tm_min,
nowtm->tm_sec,
(int)now.tv_usec/10000);
#ifdef SPF_PROFILING
gettimeofday(&t3, NULL);
#endif
/*
* In the path tree we have all the reachable nodes in our topology.
*/
for (; !list_is_empty(&path_list); list_remove(path_list.next)) {
vert = path_list.next->data;
link = vert->next_hop;
if (!link) {
OLSR_PRINTF(2, "%s no next-hop\n", olsr_ip_to_string(&vert->addr));
continue;
}
/* find the interface for the found link */
inter = link->if_name ? if_ifwithname(link->if_name)
: if_ifwithaddr(&link->local_iface_addr);
/* interface is up ? */
if (inter) {
/* add a route to the main address of the destination node */
olsr_insert_routing_table(&vert->addr, olsr_cnf->maxplen, &vert->addr,
&link->neighbor_iface_addr, inter->if_index,
vert->hops, vert->path_etx);
/* add routes to the remaining interfaces of the destination node */
for (mid_walker = mid_lookup_aliases(&vert->addr);
mid_walker != NULL;
mid_walker = mid_walker->next_alias) {
olsr_insert_routing_table(&mid_walker->alias, olsr_cnf->maxplen, &vert->addr,
&link->neighbor_iface_addr, inter->if_index,
vert->hops, vert->path_etx);
}
/* find the node's HNAs */
hna_gw = olsr_lookup_hna_gw(&vert->addr);
/* node doesn't announce any HNAs */
if (!hna_gw) {
continue;
}
/* loop through the node's HNAs */
for (hna = hna_gw->networks.next;
hna != &hna_gw->networks;
hna = hna->next) {
plen = olsr_get_hna_prefix_len(hna);
if (vert->path_etx != INFINITE_ETX)
olsr_insert_routing_table(&hna->A_network_addr, plen, &vert->addr,
&link->neighbor_iface_addr, inter->if_index,
vert->hops, vert->path_etx);
}
}
}
#ifdef SPF_PROFILING
gettimeofday(&t4, NULL);
#endif
/* move the route changes into the kernel */
olsr_update_kernel_routes();
#ifdef SPF_PROFILING
gettimeofday(&t5, NULL);
#endif
#ifdef SPF_PROFILING
timersub(&t2, &t1, &spf_init);
timersub(&t3, &t2, &spf_run);
timersub(&t4, &t3, &route);
timersub(&t5, &t4, &kernel);
timersub(&t5, &t1, &total);
olsr_printf(1, "\n--- SPF-stats for %d nodes, %d routes (total/init/run/route/kern): "
"%d, %d, %d, %d, %d\n",
path_count, routingtree.count,
(int)total.tv_usec, (int)spf_init.tv_usec, (int)spf_run.tv_usec,
(int)route.tv_usec, (int)kernel.tv_usec);
#endif
}
/*
* Local Variables:
* c-basic-offset: 2
* End:
*/
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