Merge pull request #447 from ariard/2020-01-fix-weight-computation

[rust-lightning] / lightning / src / ln / chan_utils.rs

diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs
index 19a07aaa19c2ea2c30f5498aee3c32278f7cb0c2..263547204c415a963e2223c50da0a9841f2e61e1 100644 (file)
--- a/lightning/src/ln/chan_utils.rs
+++ b/lightning/src/ln/chan_utils.rs
@@ -25,6 +25,25 @@ use secp256k1;
 pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
 pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
 
+#[derive(PartialEq)]
+pub(crate) enum HTLCType {
+       AcceptedHTLC,
+       OfferedHTLC
+}
+
+impl HTLCType {
+       /// Check if a given tx witnessScript len matchs one of a pre-signed HTLC
+       pub(crate) fn scriptlen_to_htlctype(witness_script_len: usize) ->  Option<HTLCType> {
+               if witness_script_len == 133 {
+                       Some(HTLCType::OfferedHTLC)
+               } else if witness_script_len >= 136 && witness_script_len <= 139 {
+                       Some(HTLCType::AcceptedHTLC)
+               } else {
+                       None
+               }
+       }
+}
+
 // Various functions for key derivation and transaction creation for use within channels. Primarily
 // used in Channel and ChannelMonitor.