For the SSSP algorithm Dijkstra's seems to be a nice choice. Currently a
simple breadth-first search is presented here.
- The SSSP algorithm will also be used to determine whether nodes are directly,
- indirectly or not reachable from the source. It will also set the correct
- destination address and port of a node if possible.
+ The SSSP algorithm will also be used to determine whether nodes are
+ reachable from the source. It will also set the correct destination address
+ and port of a node if possible.
*/
#include "system.h"
Please note that sorting on weight is already done by add_edge().
*/
-static void mst_kruskal(void) {
+static void mst_kruskal(meshlink_handle_t *mesh) {
/* Clear MST status on connections */
- for list_each(connection_t, c, connection_list)
+ for list_each(connection_t, c, mesh->connections) {
c->status.mst = false;
+ }
- logger(DEBUG_SCARY_THINGS, LOG_DEBUG, "Running Kruskal's algorithm:");
+ logger(mesh, MESHLINK_DEBUG, "Running Kruskal's algorithm:");
/* Clear visited status on nodes */
- for splay_each(node_t, n, mesh->nodes)
+ for splay_each(node_t, n, mesh->nodes) {
n->status.visited = false;
+ }
/* Starting point */
e->from->status.visited = true;
e->to->status.visited = true;
- if(e->connection)
+ if(e->connection) {
e->connection->status.mst = true;
+ }
- if(e->reverse->connection)
+ if(e->reverse->connection) {
e->reverse->connection->status.mst = true;
+ }
- logger(DEBUG_SCARY_THINGS, LOG_DEBUG, " Adding edge %s - %s weight %d", e->from->name, e->to->name, e->weight);
+ logger(mesh, MESHLINK_DEBUG, " Adding edge %s - %s weight %d", e->from->name, e->to->name, e->weight);
if(skipped) {
skipped = false;
Running time: O(E)
*/
-static void sssp_bfs(void) {
+static void sssp_bfs(meshlink_handle_t *mesh) {
list_t *todo_list = list_alloc(NULL);
/* Clear visited status on nodes */
for splay_each(node_t, n, mesh->nodes) {
n->status.visited = false;
- n->status.indirect = true;
n->distance = -1;
}
/* Begin with mesh->self */
mesh->self->status.visited = true;
- mesh->self->status.indirect = false;
mesh->self->nexthop = mesh->self;
mesh->self->prevedge = NULL;
- mesh->self->via = mesh->self;
mesh->self->distance = 0;
list_insert_head(todo_list, mesh->self);
/* Loop while todo_list is filled */
for list_each(node_t, n, todo_list) { /* "n" is the node from which we start */
- logger(DEBUG_SCARY_THINGS, LOG_DEBUG, " Examining edges from %s", n->name);
+ logger(mesh, MESHLINK_DEBUG, " Examining edges from %s", n->name);
- if(n->distance < 0)
+ if(n->distance < 0) {
abort();
+ }
for splay_each(edge_t, e, n->edge_tree) { /* "e" is the edge connected to "from" */
- if(!e->reverse)
+ if(!e->reverse) {
continue;
+ }
/* Situation:
- /
- /
+ /
+ /
----->(n)---e-->(e->to)
- \
- \
+ \
+ \
Where e is an edge, (n) and (e->to) are nodes.
n->address is set to the e->address of the edge left of n to n.
of nodes behind it.
*/
- bool indirect = n->status.indirect || e->options & OPTION_INDIRECT;
-
if(e->to->status.visited
- && (!e->to->status.indirect || indirect)
- && (e->to->distance != n->distance + 1 || e->weight >= e->to->prevedge->weight))
+ && (e->to->distance != n->distance + 1 || e->weight >= e->to->prevedge->weight)) {
continue;
+ }
e->to->status.visited = true;
- e->to->status.indirect = indirect;
e->to->nexthop = (n->nexthop == mesh->self) ? e->to : n->nexthop;
e->to->prevedge = e;
- e->to->via = indirect ? n->via : e->to;
- e->to->options = e->options;
e->to->distance = n->distance + 1;
- if(!e->to->status.reachable || (e->to->address.sa.sa_family == AF_UNSPEC && e->address.sa.sa_family != AF_UNKNOWN))
- update_node_udp(e->to, &e->address);
+ if(!e->to->status.reachable || (e->to->address.sa.sa_family == AF_UNSPEC && e->address.sa.sa_family != AF_UNKNOWN)) {
+ update_node_udp(mesh, e->to, &e->address);
+ }
list_insert_tail(todo_list, e->to);
}
list_free(todo_list);
}
-static void check_reachability(void) {
+static void check_reachability(meshlink_handle_t *mesh) {
/* Check reachability status. */
for splay_each(node_t, n, mesh->nodes) {
if(n->status.visited != n->status.reachable) {
n->status.reachable = !n->status.reachable;
- n->last_state_change = now.tv_sec;
+ n->last_state_change = mesh->loop.now.tv_sec;
if(n->status.reachable) {
- logger(DEBUG_TRAFFIC, LOG_DEBUG, "Node %s (%s) became reachable",
- n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Node %s became reachable", n->name);
} else {
- logger(DEBUG_TRAFFIC, LOG_DEBUG, "Node %s (%s) became unreachable",
- n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Node %s became unreachable", n->name);
}
/* TODO: only clear status.validkey if node is unreachable? */
n->minmtu = 0;
n->mtuprobes = 0;
- timeout_del(&n->mtutimeout);
+ timeout_del(&mesh->loop, &n->mtutimeout);
- //TODO: callback to application to inform of this node going up/down
+ if(!n->status.blacklisted) {
+ update_node_status(mesh, n);
+ }
if(!n->status.reachable) {
- update_node_udp(n, NULL);
- memset(&n->status, 0, sizeof n->status);
- n->options = 0;
+ update_node_udp(mesh, n, NULL);
+ n->status.broadcast = false;
} else if(n->connection) {
- if(n->connection->outgoing)
- send_req_key(n);
+ if(n->connection->status.initiator) {
+ send_req_key(mesh, n);
+ }
+ }
+
+ if(n->utcp) {
+ utcp_offline(n->utcp, !n->status.reachable);
}
}
}
}
-void graph(void) {
- sssp_bfs();
- check_reachability();
- mst_kruskal();
+void graph(meshlink_handle_t *mesh) {
+ sssp_bfs(mesh);
+ check_reachability(mesh);
+ mst_kruskal(mesh);
}
projects / meshlink / blobdiff