Files
palladum-lightning/plugins/askrene/child/route_query.c
2026-02-19 17:04:35 +10:30

54 lines
1.6 KiB
C

#include "config.h"
#include <common/gossmap.h>
#include <plugins/askrene/child/additional_costs.h>
#include <plugins/askrene/child/route_query.h>
#include <plugins/askrene/layer.h>
#include <plugins/askrene/reserve.h>
struct amount_msat get_additional_per_htlc_cost(const struct route_query *rq,
const struct short_channel_id_dir *scidd)
{
const struct per_htlc_cost *phc;
phc = additional_cost_htable_get(rq->additional_costs, scidd);
if (phc)
return phc->per_htlc_cost;
else
return AMOUNT_MSAT(0);
}
void get_constraints(const struct route_query *rq,
const struct gossmap_chan *chan,
int dir,
struct amount_msat *min,
struct amount_msat *max)
{
struct short_channel_id_dir scidd;
size_t idx = gossmap_chan_idx(rq->gossmap, chan);
*min = AMOUNT_MSAT(0);
/* Fast path: no information known, no reserve. */
if (idx < tal_count(rq->capacities) && rq->capacities[idx] != 0) {
*max = amount_msat(fp16_to_u64(rq->capacities[idx]) * 1000);
return;
}
/* Naive implementation! */
scidd.scid = gossmap_chan_scid(rq->gossmap, chan);
scidd.dir = dir;
*max = AMOUNT_MSAT(-1ULL);
/* Look through layers for any constraints (might be dummy
* ones, for created channels!) */
for (size_t i = 0; i < tal_count(rq->layers); i++)
layer_apply_constraints(rq->layers[i], &scidd, min, max);
/* Might be here because it's reserved, but capacity is normal. */
if (amount_msat_eq(*max, AMOUNT_MSAT(-1ULL)))
*max = gossmap_chan_get_capacity(rq->gossmap, chan);
/* Finally, if any is in use, subtract that! */
reserve_sub(rq->reserved, &scidd, rq->layers, min);
reserve_sub(rq->reserved, &scidd, rq->layers, max);
}