/*
graph.c -- graph algorithms
- Copyright (C) 2001-2013 Guus Sliepen <guus@tinc-vpn.org>,
+ Copyright (C) 2001-2014 Guus Sliepen <guus@tinc-vpn.org>,
2001-2005 Ivo Timmermans
This program is free software; you can redistribute it and/or modify
/* Do we have something to do at all? */
- if(!edge_weight_tree->head)
+ if(!edge_weight_tree->head) {
return;
+ }
ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Running Kruskal's algorithm:");
for(node = edge_weight_tree->head; node; node = node->next) {
e = node->data;
+
if(e->from->status.reachable) {
e->from->status.visited = true;
break;
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;
+ }
safe_edges++;
ifdebug(SCARY_THINGS) logger(LOG_DEBUG, " Adding edge %s - %s weight %d", e->from->name,
- e->to->name, e->weight);
+ e->to->name, e->weight);
if(skipped) {
skipped = false;
}
ifdebug(SCARY_THINGS) logger(LOG_DEBUG, "Done, counted %d nodes and %d safe edges.", nodes,
- safe_edges);
+ safe_edges);
}
/* Implementation of a simple breadth-first search algorithm.
/* Loop while todo_list is filled */
- for(from = todo_list->head; from; from = todonext) { /* "from" is the node from which we start */
+ for(from = todo_list->head; from; from = todonext) { /* "from" is the node from which we start */
n = from->data;
- for(to = n->edge_tree->head; to; to = to->next) { /* "to" is the edge connected to "from" */
+ for(to = n->edge_tree->head; to; to = to->next) { /* "to" is the edge connected to "from" */
e = to->data;
- 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.
indirect = n->status.indirect || e->options & OPTION_INDIRECT;
if(e->to->status.visited
- && (!e->to->status.indirect || indirect))
+ && (!e->to->status.indirect || indirect)) {
continue;
+ }
+
+ // Only update nexthop the first time we visit this node.
+
+ if(!e->to->status.visited) {
+ e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
+ }
e->to->status.visited = true;
e->to->status.indirect = indirect;
- e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
e->to->prevedge = e;
e->to->via = indirect ? n->via : e->to;
e->to->options = e->options;
- if(e->to->address.sa.sa_family == AF_UNSPEC && e->address.sa.sa_family != AF_UNKNOWN)
+ if(e->to->address.sa.sa_family == AF_UNSPEC && e->address.sa.sa_family != AF_UNKNOWN) {
update_node_udp(e->to, &e->address);
+ }
list_insert_tail(todo_list, e->to);
}
if(n->status.reachable) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Node %s (%s) became reachable",
- n->name, n->hostname);
+ n->name, n->hostname);
} else {
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Node %s (%s) became unreachable",
- n->name, n->hostname);
+ n->name, n->hostname);
}
/* TODO: only clear status.validkey if node is unreachable? */
execute_script(n->status.reachable ? "host-up" : "host-down", envp);
xasprintf(&name,
- n->status.reachable ? "hosts/%s-up" : "hosts/%s-down",
- n->name);
+ n->status.reachable ? "hosts/%s-up" : "hosts/%s-down",
+ n->name);
execute_script(name, envp);
free(name);
free(address);
free(port);
- for(i = 0; i < 7; i++)
+ for(i = 0; i < 7; i++) {
free(envp[i]);
+ }
subnet_update(n, NULL, n->status.reachable);
if(!n->status.reachable) {
update_node_udp(n, NULL);
- memset(&n->status, 0, sizeof n->status);
+ memset(&n->status, 0, sizeof(n->status));
n->options = 0;
} else if(n->connection) {
send_ans_key(n);
/* Dump nodes and edges to a graphviz file.
-
+
The file can be converted to an image with
dot -Tpng graph_filename -o image_filename.png -Gconcentrate=true
*/
edge_t *e;
char *filename = NULL, *tmpname = NULL;
FILE *file, *pipe = NULL;
-
- if(!graph_changed || !get_config_string(lookup_config(config_tree, "GraphDumpFile"), &filename))
+
+ if(!graph_changed || !get_config_string(lookup_config(config_tree, "GraphDumpFile"), &filename)) {
return;
+ }
graph_changed = false;
ifdebug(PROTOCOL) logger(LOG_NOTICE, "Dumping graph");
-
+
if(filename[0] == '|') {
file = pipe = popen(filename + 1, "w");
} else {
if(!file) {
logger(LOG_ERR, "Unable to open graph dump file %s: %s", filename, strerror(errno));
+ free(filename);
free(tmpname);
return;
}
fprintf(file, "digraph {\n");
-
+
/* dump all nodes first */
for(node = node_tree->head; node; node = node->next) {
n = node->data;
fprintf(file, " %s -> %s;\n", e->from->name, e->to->name);
}
- fprintf(file, "}\n");
-
+ fprintf(file, "}\n");
+
if(pipe) {
pclose(pipe);
} else {
#ifdef HAVE_MINGW
unlink(filename);
#endif
- rename(tmpname, filename);
+
+ if(rename(tmpname, filename)) {
+ logger(LOG_ERR, "Could not rename %s to %s: %s\n", tmpname, filename, strerror(errno));
+ }
+
free(tmpname);
}
+
+ free(filename);
}