Fix bug in shortest path implementation

diff --git a/src/graph.c b/src/graph.c
index 5a7a16a..5bec2c1 100644 (file)
--- a/src/graph.c
+++ b/src/graph.c
@@ -141,6 +141,7 @@ void sssp_bfs(void) {
        myself->prevedge = NULL;
        myself->via = myself;
        myself->distance = 0;
+       myself->weighted_distance = 0;
        list_insert_head(todo_list, myself);
 
        /* Loop while todo_list is filled */
@@ -178,14 +179,15 @@ void sssp_bfs(void) {
 
                        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->to->weighted_distance <= n->weighted_distance + e->weight)) {
                                continue;
                        }
 
                        // Only update nexthop if it doesn't increase the path length
 
-                       if(!e->to->status.visited || (e->to->distance == n->distance + 1 && e->weight < e->to->prevedge->weight)) {
+                       if(!e->to->status.visited || (e->to->distance == n->distance + 1 && e->to->weighted_distance > n->weighted_distance + e->weight)) {
                                e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop;
+                               e->to->weighted_distance = n->weighted_distance + e->weight;
                        }
 
                        e->to->status.visited = true;

diff --git a/src/node.h b/src/node.h
index 51322c2..7d5a0c8 100644 (file)
--- a/src/node.h
+++ b/src/node.h
@@ -76,6 +76,7 @@ typedef struct node_t {
        compression_level_t outcompression;     /* Compression level, 0 = no compression */
 
        int distance;
+       int weighted_distance;
        struct node_t *nexthop;                 /* nearest node from us to him */
        struct edge_t *prevedge;                /* nearest node from him to us */
        struct node_t *via;                     /* next hop for UDP packets */