Function chan_extra_adjust_half

plugins/renepay/chan_extra.c:239–256

This helper function preserves the uncertainty network invariant after the * knowledge is updated. It assumes that the (channel,!dir) knowledge is * correct. */

 * knowledge is updated. It assumes that the (channel,!dir) knowledge is
 * correct. */
static enum renepay_errorcode chan_extra_adjust_half(struct chan_extra *ce,
						     int dir)
{
	assert(ce);
	assert(dir == 0 || dir == 1);

	struct amount_msat new_known_max, new_known_min;

	if (!amount_msat_sub(&new_known_max, ce->capacity,
			     ce->half[!dir].known_min) ||
	    !amount_msat_sub(&new_known_min, ce->capacity,
			     ce->half[!dir].known_max))
		return RENEPAY_AMOUNT_OVERFLOW;

	ce->half[dir].known_max = new_known_max;
	ce->half[dir].known_min = new_known_min;
	return RENEPAY_NOERROR;
}

/* Update the knowledge that this (channel,direction) can send x msat.*/
static enum renepay_errorcode