Update copyright information.
[tinc] / src / graph.c
index 3ed1d72..5dfbb72 100644 (file)
@@ -1,7 +1,7 @@
 /*
     graph.c -- graph algorithms
-    Copyright (C) 2001-2003 Guus Sliepen <guus@sliepen.eu.org>,
-                  2001-2003 Ivo Timmermans <ivo@o2w.nl>
+    Copyright (C) 2001-2007 Guus Sliepen <guus@tinc-vpn.org>,
+                  2001-2005 Ivo Timmermans
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id: graph.c,v 1.1.2.34 2003/12/22 11:04:16 guus Exp $
+    $Id$
 */
 
 /* We need to generate two trees from the graph:
@@ -47,6 +47,7 @@
 #include "system.h"
 
 #include "avl_tree.h"
+#include "config.h"
 #include "connection.h"
 #include "device.h"
 #include "edge.h"
 #include "netutl.h"
 #include "node.h"
 #include "process.h"
+#include "subnet.h"
 #include "utils.h"
 
+static bool graph_changed = true;
+
 /* Implementation of Kruskal's algorithm.
    Running time: O(EN)
    Please note that sorting on weight is already done by add_edge().
@@ -97,7 +101,13 @@ void mst_kruskal(void)
 
        /* Starting point */
 
-       ((edge_t *) edge_weight_tree->head->data)->from->status.visited = true;
+       for(node = edge_weight_tree->head; node; node = node->next) {
+               e = node->data;
+               if(e->from->status.reachable) {
+                       e->from->status.visited = true;
+                       break;
+               }
+       }
 
        /* Add safe edges */
 
@@ -141,10 +151,11 @@ void mst_kruskal(void)
 
 void sssp_bfs(void)
 {
-       avl_node_t *node, *from, *next, *to;
+       avl_node_t *node, *next, *to;
        edge_t *e;
        node_t *n;
-       avl_tree_t *todo_tree;
+       list_t *todo_list;
+       list_node_t *from, *todonext;
        bool indirect;
        char *name;
        char *address, *port;
@@ -153,7 +164,7 @@ void sssp_bfs(void)
 
        cp();
 
-       todo_tree = avl_alloc_tree(NULL, NULL);
+       todo_list = list_alloc(NULL);
 
        /* Clear visited status on nodes */
 
@@ -169,86 +180,82 @@ void sssp_bfs(void)
        myself->status.indirect = false;
        myself->nexthop = myself;
        myself->via = myself;
-       node = avl_alloc_node();
-       node->data = myself;
-       avl_insert_top(todo_tree, node);
+       list_insert_head(todo_list, myself);
+
+       /* Loop while todo_list is filled */
 
-       /* Loop while todo_tree is filled */
+       for(from = todo_list->head; from; from = todonext) {    /* "from" is the node from which we start */
+               n = from->data;
 
-       while(todo_tree->head) {
-               for(from = todo_tree->head; from; from = next) {        /* "from" is the node from which we start */
-                       next = from->next;
-                       n = from->data;
+               for(to = n->edge_tree->head; to; to = to->next) {       /* "to" is the edge connected to "from" */
+                       e = to->data;
 
-                       for(to = n->edge_tree->head; to; to = to->next) {       /* "to" is the edge connected to "from" */
-                               e = to->data;
+                       if(!e->reverse)
+                               continue;
 
-                               if(!e->reverse)
-                                       continue;
+                       /* Situation:
 
-                               /* Situation:
+                                  /
+                                 /
+                          ----->(n)---e-->(e->to)
+                                 \
+                                  \
 
-                                          /
-                                         /
-                                  ----->(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.
+                          We are currently examining the edge e right of n from n:
 
-                                  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.
-                                  We are currently examining the edge e right of n from n:
+                          - If e->reverse->address != n->address, then e->to is probably
+                            not reachable for the nodes left of n. We do as if the indirectdata
+                            flag is set on edge e.
+                          - If edge e provides for better reachability of e->to, update
+                            e->to and (re)add it to the todo_list to (re)examine the reachability
+                            of nodes behind it.
+                        */
 
-                                  - If e->reverse->address != n->address, then e->to is probably
-                                    not reachable for the nodes left of n. We do as if the indirectdata
-                                    flag is set on edge e.
-                                  - If edge e provides for better reachability of e->to, update
-                                    e->to and (re)add it to the todo_tree to (re)examine the reachability
-                                    of nodes behind it.
-                                */
+                       indirect = n->status.indirect || e->options & OPTION_INDIRECT
+                               || ((n != myself) && sockaddrcmp(&n->address, &e->reverse->address));
 
-                               indirect = n->status.indirect || e->options & OPTION_INDIRECT
-                                       || ((n != myself) && sockaddrcmp(&n->address, &e->reverse->address));
+                       if(e->to->status.visited
+                          && (!e->to->status.indirect || indirect))
+                               continue;
 
-                               if(e->to->status.visited
-                                  && (!e->to->status.indirect || indirect))
-                                       continue;
+                       e->to->status.visited = true;
+                       e->to->status.indirect = indirect;
+                       e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
+                       e->to->via = indirect ? n->via : e->to;
+                       e->to->options = e->options;
 
-                               e->to->status.visited = true;
-                               e->to->status.indirect = indirect;
-                               e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
-                               e->to->via = indirect ? n->via : e->to;
-                               e->to->options = e->options;
+                       if(sockaddrcmp(&e->to->address, &e->address)) {
+                               node = avl_unlink(node_udp_tree, e->to);
+                               sockaddrfree(&e->to->address);
+                               sockaddrcpy(&e->to->address, &e->address);
 
-                               if(sockaddrcmp(&e->to->address, &e->address)) {
-                                       node = avl_unlink(node_udp_tree, e->to);
-                                       sockaddrfree(&e->to->address);
-                                       sockaddrcpy(&e->to->address, &e->address);
+                               if(e->to->hostname)
+                                       free(e->to->hostname);
 
-                                       if(e->to->hostname)
-                                               free(e->to->hostname);
+                               e->to->hostname = sockaddr2hostname(&e->to->address);
 
-                                       e->to->hostname = sockaddr2hostname(&e->to->address);
+                               if(node)
                                        avl_insert_node(node_udp_tree, node);
 
-                                       if(e->to->options & OPTION_PMTU_DISCOVERY) {
-                                               e->to->mtuprobes = 0;
-                                               e->to->minmtu = 0;
-                                               e->to->maxmtu = MTU;
-                                               if(e->to->status.validkey)
-                                                       send_mtu_probe(e->to);
-                                       }
+                               if(e->to->options & OPTION_PMTU_DISCOVERY) {
+                                       e->to->mtuprobes = 0;
+                                       e->to->minmtu = 0;
+                                       e->to->maxmtu = MTU;
+                                       if(e->to->status.validkey)
+                                               send_mtu_probe(e->to);
                                }
-
-                               node = avl_alloc_node();
-                               node->data = e->to;
-                               avl_insert_before(todo_tree, from, node);
                        }
 
-                       avl_delete_node(todo_tree, from);
+                       list_insert_tail(todo_list, e->to);
                }
+
+               todonext = from->next;
+               list_delete_node(todo_list, from);
        }
 
-       avl_free_tree(todo_tree);
+       list_free(todo_list);
 
        /* Check reachability status. */
 
@@ -262,9 +269,11 @@ void sssp_bfs(void)
                        if(n->status.reachable) {
                                ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Node %s (%s) became reachable"),
                                           n->name, n->hostname);
+                               avl_insert(node_udp_tree, n);
                        } else {
                                ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Node %s (%s) became unreachable"),
                                           n->name, n->hostname);
+                               avl_delete(node_udp_tree, n);
                        }
 
                        n->status.validkey = false;
@@ -283,6 +292,8 @@ void sssp_bfs(void)
                        asprintf(&envp[5], "REMOTEPORT=%s", port);
                        envp[6] = NULL;
 
+                       execute_script(n->status.reachable ? "host-up" : "host-down", envp);
+
                        asprintf(&name,
                                         n->status.reachable ? "hosts/%s-up" : "hosts/%s-down",
                                         n->name);
@@ -292,14 +303,81 @@ void sssp_bfs(void)
                        free(address);
                        free(port);
 
-                       for(i = 0; i < 7; i++)
+                       for(i = 0; i < 6; i++)
                                free(envp[i]);
+
+                       subnet_update(n, NULL, n->status.reachable);
                }
        }
 }
 
 void graph(void)
 {
-       mst_kruskal();
        sssp_bfs();
+       mst_kruskal();
+       graph_changed = true;
+}
+
+
+
+/* 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
+*/
+
+void dump_graph(void)
+{
+       avl_node_t *node;
+       node_t *n;
+       edge_t *e;
+       char *filename = NULL, *tmpname = NULL;
+       FILE *file;
+       
+       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 = popen(filename + 1, "w");
+       } else {
+               asprintf(&tmpname, "%s.new", filename);
+               file = fopen(tmpname, "w");
+       }
+
+       if(!file) {
+               logger(LOG_ERR, "Unable to open graph dump file %s: %s", filename, strerror(errno));
+               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 [label = \"%s\"];\n", n->name, n->name);
+       }
+
+       /* now dump all edges */
+       for(node = edge_weight_tree->head; node; node = node->next) {
+               e = node->data;
+               fprintf(file, " %s -> %s;\n", e->from->name, e->to->name);
+       }
+
+       fprintf(file, "}\n");   
+       
+       if(filename[0] == '|') {
+               pclose(file);
+       } else {
+               fclose(file);
+#ifdef HAVE_MINGW
+               unlink(filename);
+#endif
+               rename(tmpname, filename);
+               free(tmpname);
+       }
 }