Function dijkstra_to_hops

common/route.c:69–122

Recursive version: return false if we can't get there. * * amount and cltv are updated, and reflect the amount we * and delay would have to put into the first channel (usually * ignored, since we don't pay for our own channels!). */

 * ignored, since we don't pay for our own channels!).
 */
static bool dijkstra_to_hops(struct route_hop **hops,
			     const struct gossmap *gossmap,
			     const struct dijkstra *dij,
			     const struct gossmap_node *cur,
			     struct amount_msat *amount,
			     u32 *cltv)
{
	u32 curidx = gossmap_node_idx(gossmap, cur);
	u32 dist = dijkstra_distance(dij, curidx);
	struct gossmap_chan *c;
	const struct gossmap_node *next;
	size_t num_hops = tal_count(*hops);
	const struct half_chan *h;

	if (dist == 0)
		return true;

	if (dist == UINT_MAX)
		return false;

	tal_resize(hops, num_hops + 1);

	/* OK, populate other fields. */
	c = dijkstra_best_chan(dij, curidx);
	if (c->half[0].nodeidx == curidx) {
		(*hops)[num_hops].direction = 0;
	} else {
		assert(c->half[1].nodeidx == curidx);
		(*hops)[num_hops].direction = 1;
	}
	(*hops)[num_hops].scid = gossmap_chan_scid(gossmap, c);

	/* Find other end of channel. */
	next = gossmap_nth_node(gossmap, c, !(*hops)[num_hops].direction);
	gossmap_node_get_id(gossmap, next, &(*hops)[num_hops].node_id);

	/* These are (ab)used by others. */
	(*hops)[num_hops].blinding = NULL;
	(*hops)[num_hops].enctlv = NULL;

	if (!dijkstra_to_hops(hops, gossmap, dij, next, amount, cltv))
		return false;

	(*hops)[num_hops].amount = *amount;
	(*hops)[num_hops].delay = *cltv;

	h = &c->half[(*hops)[num_hops].direction];
	if (!amount_msat_add_fee(amount, h->base_fee, h->proportional_fee))
		/* Shouldn't happen, since we said it would route,
		 * amounts must be sane. */
		abort();
	*cltv += h->delay;
	return true;
}

struct route_hop *route_from_dijkstra(const tal_t *ctx,
				      const struct gossmap *map,