Function remove_small_channel_layer

plugins/askrene/askrene.c:267–297

We're going to abuse MCF, and take the largest flow it gives and ram everything * through it. This is more effective if there's at least a *chance* that can handle * the full amount. * * It's far from perfect, but I have very little sympathy: if you want * to receive amounts reliably, enable MPP. */

 * to receive amounts reliably, enable MPP.
 */
static struct layer *remove_small_channel_layer(const tal_t *ctx,
						struct askrene *askrene,
						struct amount_msat min_amount,
						struct gossmap_localmods *localmods)
{
	/* We use the prefix auto. to avoid clashing */
	struct layer *layer = new_temp_layer(ctx, askrene, "auto.remove_small_channels");
	struct gossmap *gossmap = askrene->gossmap;
	struct gossmap_chan *c;

	/* We apply this so we see any created channels */
	gossmap_apply_localmods(gossmap, localmods);

	for (c = gossmap_first_chan(gossmap); c; c = gossmap_next_chan(gossmap, c)) {
		struct short_channel_id_dir scidd;
		if (amount_msat_greater_eq(gossmap_chan_get_capacity(gossmap, c),
					   min_amount))
			continue;

		scidd.scid = gossmap_chan_scid(gossmap, c);
		/* Layer will disable this in both directions */
		for (scidd.dir = 0; scidd.dir < 2; scidd.dir++) {
			const bool enabled = false;
			layer_add_update_channel(layer, &scidd, &enabled,
						 NULL, NULL, NULL, NULL, NULL);
		}
	}
	gossmap_remove_localmods(gossmap, localmods);

	return layer;
}

PRINTF_FMT(4, 5)
static const char *cmd_log(const tal_t *ctx,