Function finish_psbt

wallet/reservation.c:327–420

}

static struct command_result *finish_psbt(struct command *cmd,
					  struct utxo **utxos,
					  u32 feerate_per_kw,
					  size_t weight,
					  struct amount_sat excess,
					  u32 reserve,
					  u32 *locktime,
					  bool excess_as_change)
{
	struct json_stream *response;
	struct wally_psbt *psbt;
	size_t change_outnum COMPILER_WANTS_INIT("gcc 9.4.0 -Og");
	u32 current_height = get_block_height(cmd->ld->topology);

	/* Setting the locktime to the next block to be mined has multiple
	 * benefits:
	 * - anti fee-snipping (even if not yet likely)
	 * - less distinguishable transactions (with this we create
	 *   general-purpose transactions which looks like bitcoind:
	 *   native segwit, nlocktime set to tip, and sequence set to
	 *   0xFFFFFFFD by default. Other wallets are likely to implement
	 *   this too).
	 */
	if (!locktime) {
		locktime = tal(cmd, u32);
		*locktime = current_height;

		/* Eventually fuzz it too. */
		if (*locktime > 100 && pseudorand(10) == 0)
			*locktime -= pseudorand(100);
	}

	psbt = psbt_using_utxos(cmd, cmd->ld->wallet, utxos,
				cmd->ld->wallet->bip32_base,
				*locktime, BITCOIN_TX_RBF_SEQUENCE);

	/* Should we add a change output for the excess? */
	if (excess_as_change) {
		struct amount_sat change;
		struct pubkey pubkey;
		s64 keyidx;
		u8 *b32script;

		/* Checks for dust, returns 0sat if below dust */
		change = change_amount(excess, feerate_per_kw, weight);
		if (!amount_sat_greater(change, AMOUNT_SAT(0))) {
			excess_as_change = false;
			goto fee_calc;
		}

		/* Get a change adddress */
		keyidx = wallet_get_newindex(cmd->ld);
		if (keyidx < 0)
			return command_fail(cmd, LIGHTNINGD,
					    "Failed to generate change address."
					    " Keys exhausted.");

		if (!bip32_pubkey(cmd->ld->wallet->bip32_base, &pubkey, keyidx))