1 /* Licensed under LGPLv2+ - see LICENSE file for details */
8 #include <ccan/aga/aga.h>
12 * Breadth first search
15 static bool bfs_enqueue(struct aga_graph *g, struct lqueue *queue,
18 if (!aga_update_node(g, n))
21 lqueue_enqueue(queue, n, u.bfs.next);
22 n->u.bfs.edge = aga_first_edge(g, n);
26 static struct aga_node *bfs_front(struct lqueue *queue)
28 return lqueue_front(queue, struct aga_node, u.bfs.next);
31 static void bfs_dequeue(struct lqueue *queue)
33 lqueue_dequeue(queue, struct aga_node, u.bfs.next);
36 int aga_bfs_start(struct aga_graph *g)
47 struct aga_node *aga_bfs_explore(struct aga_graph *g, struct aga_node *n)
51 if (!aga_check_state(g))
57 if (bfs_enqueue(g, &queue, n))
60 lqueue_init_from_back(&queue, n, u.bfs.next);
62 while ((n = bfs_front(&queue))) {
63 const void *e = n->u.bfs.edge;
65 struct aga_edge_info ei;
68 /* out of edges, back up */
73 n->u.bfs.edge = aga_next_edge(g, n, e);
75 err = aga_edge_info(g, n, e, &ei);
85 if (!bfs_enqueue(g, &queue, ei.to)) {
86 /* already visited node */