Function calc_weight

plugins/spender/splice.c:864–965

}

static size_t calc_weight(struct splice_cmd *splice_cmd,
			  bool simulate_wallet_outputs)
{
	struct splice_script_result *action;
	struct plugin *plugin = splice_cmd->cmd->plugin;
	struct wally_psbt *psbt = splice_cmd->psbt;
	size_t lweight = 0, weight = 0;
	size_t extra_inputs = 0;
	size_t extra_outputs = 0;
	bool add_wallet_output = output_wallet(splice_cmd) ? true : false;

	plugin_log(plugin, LOG_DBG, "Counting potenetial tx weight;");

	/* BOLT #2:
	 * The rest of the transaction bytes' fees are the responsibility of
	 * the peer who contributed that input or output via `tx_add_input` or
	 * `tx_add_output`, at the agreed upon `feerate`.
	 */
	for (size_t i = 0; i < psbt->num_inputs; i++) {
		weight += psbt_input_get_weight(psbt, i, PSBT_GUESS_2OF2);
		plugin_log(plugin, LOG_DBG, " Counting input; weight: %zu",
			   weight - lweight);
		lweight = weight;
	}

	if (unresolved_wallet_inputs(splice_cmd)) {
		add_wallet_output = true;
		weight += bitcoin_tx_input_weight(false,
						  bitcoin_tx_input_witness_weight(UTXO_P2TR) - 1);
		plugin_log(plugin, LOG_DBG, " Simulating input (wallet);"
			   " weight: %zu", weight - lweight);
		lweight = weight;
	}

	/* Count the splice input manually */
	for (size_t i = 0; i < tal_count(splice_cmd->actions); i++) {
		action = splice_cmd->actions[i];
		if (action->channel_id) {
			weight += bitcoin_tx_input_weight(false,
							  bitcoin_tx_2of2_input_witness_weight() - 1);
			plugin_log(plugin, LOG_DBG, " Simulating input"
				   " (channel); weight:"
				   " %zu", weight - lweight);
			lweight = weight;
			extra_inputs++;
		}
	}

	/* Count the splice outputs manually */
	for (size_t i = 0; i < tal_count(splice_cmd->actions); i++) {
		action = splice_cmd->actions[i];
		if (action->onchain_wallet) {
			if (!amount_sat_is_zero(action->in_sat) || action->in_ppm)
				add_wallet_output = true;
			assert(!splice_cmd->actions[i]->channel_id);
		}
		if (splice_cmd->actions[i]->channel_id) {
			weight += bitcoin_tx_output_weight(BITCOIN_SCRIPTPUBKEY_P2WSH_LEN);