Adjust HTLC_{SUCCESS,TIMEOUT}_TX_WEIGHT when anchors used

diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs
index 223ef1ec1e5d8e469f67525299c51d11ac8870d6..f3520b3035e77dbefc9888a8374830838a246263 100644 (file)
--- a/lightning/src/ln/chan_utils.rs
+++ b/lightning/src/ln/chan_utils.rs
@@ -45,6 +45,20 @@ pub(crate) const MAX_HTLCS: u16 = 483;
 pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
 pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
 
+/// Gets the weight for an HTLC-Success transaction.
+#[inline]
+pub fn htlc_success_tx_weight(opt_anchors: bool) -> u64 {
+       const HTLC_SUCCESS_ANCHOR_TX_WEIGHT: u64 = 706;
+       if opt_anchors { HTLC_SUCCESS_ANCHOR_TX_WEIGHT } else { HTLC_SUCCESS_TX_WEIGHT }
+}
+
+/// Gets the weight for an HTLC-Timeout transaction.
+#[inline]
+pub fn htlc_timeout_tx_weight(opt_anchors: bool) -> u64 {
+       const HTLC_TIMEOUT_ANCHOR_TX_WEIGHT: u64 = 666;
+       if opt_anchors { HTLC_TIMEOUT_ANCHOR_TX_WEIGHT } else { HTLC_TIMEOUT_TX_WEIGHT }
+}
+
 #[derive(PartialEq)]
 pub(crate) enum HTLCType {
        AcceptedHTLC,
@@ -598,11 +612,12 @@ pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, conte
                witness: Vec::new(),
        });
 
-       let total_fee = if htlc.offered {
-                       feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000
-               } else {
-                       feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000
-               };
+       let weight = if htlc.offered {
+               htlc_timeout_tx_weight(opt_anchors)
+       } else {
+               htlc_success_tx_weight(opt_anchors)
+       };
+       let total_fee = feerate_per_kw as u64 * weight / 1000;
 
        let mut txouts: Vec<TxOut> = Vec::new();
        txouts.push(TxOut {