Function flow_probability

plugins/askrene/child/flow.c:130–155

Helper function to find the success_prob for a single flow * * IMPORTANT: flow->success_prob is misleading, because that's the prob. of * success provided that there are no other flows in the current MPP flow set. * */

 * success provided that there are no other flows in the current MPP flow set.
 * */
double flow_probability(const struct flow *flow,
			const struct route_query *rq)
{
	const size_t pathlen = tal_count(flow->path);
	struct amount_msat spend = flow->delivers;
	double prob = 1.0;

	for (int i = (int)pathlen - 1; i >= 0; i--) {
		const struct half_chan *h = flow_edge(flow, i);
		struct short_channel_id_dir scidd;
		scidd.scid = gossmap_chan_scid(rq->gossmap, flow->path[i]);
		scidd.dir = flow->dirs[i];

		prob *= edge_probability(rq, &scidd, spend);

		if (!amount_msat_add_fee(&spend, h->base_fee,
					 h->proportional_fee)) {
			child_err("Could not add fee %u/%u to amount %s in %i/%zu",
				  h->base_fee, h->proportional_fee,
				  fmt_amount_msat(tmpctx, spend),
				  i, pathlen);
		}
	}

	return prob;
}

u64 flow_delay(const struct flow *flow)
{