From fecb4f25de7424d0bc846bdb34f90d7b8a16439b Mon Sep 17 00:00:00 2001
From: Matt Corallo <git@bluematt.me>
Date: Sun, 31 Jan 2021 20:12:50 -0500
Subject: [PATCH] Make ChannelMonitor clonable again

In general, we'd been moving away from ChannelMonitor being clonable,
   XXXXXXXXXXXXXXXXXXXx
---
 lightning/src/chain/channelmonitor.rs | 16 +++++++++++-----
 lightning/src/chain/keysinterface.rs  |  2 +-
 lightning/src/chain/onchaintx.rs      |  5 +++--
 3 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index c0fbb6a98..5eef3fb94 100644
--- a/lightning/src/chain/channelmonitor.rs
+++ b/lightning/src/chain/channelmonitor.rs
@@ -284,7 +284,7 @@ impl HolderSignedTx {
 
 /// We use this to track static counterparty commitment transaction data and to generate any
 /// justice or 2nd-stage preimage/timeout transactions.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 struct CounterpartyCommitmentParameters {
 	counterparty_delayed_payment_base_key: PublicKey,
 	counterparty_htlc_base_key: PublicKey,
@@ -338,7 +338,7 @@ impl Readable for CounterpartyCommitmentParameters {
 /// observed, as well as the transaction causing it.
 ///
 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 struct OnchainEventEntry {
 	txid: Txid,
 	height: u32,
@@ -381,7 +381,7 @@ type CommitmentTxCounterpartyOutputInfo = Option<(u32, u64)>;
 
 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 enum OnchainEvent {
 	/// An outbound HTLC failing after a transaction is confirmed. Used
 	///  * when an outbound HTLC output is spent by us after the HTLC timed out
@@ -644,7 +644,7 @@ pub enum Balance {
 }
 
 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 struct IrrevocablyResolvedHTLC {
 	commitment_tx_output_idx: Option<u32>,
 	/// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
@@ -717,7 +717,13 @@ pub struct ChannelMonitor<Signer: WriteableEcdsaChannelSigner> {
 	inner: Mutex<ChannelMonitorImpl<Signer>>,
 }
 
-#[derive(PartialEq)]
+impl<Signer: WriteableEcdsaChannelSigner> Clone for ChannelMonitor<Signer> {
+	fn clone(&self) -> Self {
+		Self { inner: Mutex::new(self.inner.lock().unwrap().clone()) }
+	}
+}
+
+#[derive(Clone, PartialEq)]
 pub(crate) struct ChannelMonitorImpl<Signer: WriteableEcdsaChannelSigner> {
 	latest_update_id: u64,
 	commitment_transaction_number_obscure_factor: u64,
diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs
index b1290708b..74f8ff85c 100644
--- a/lightning/src/chain/keysinterface.rs
+++ b/lightning/src/chain/keysinterface.rs
@@ -426,7 +426,7 @@ pub trait EcdsaChannelSigner: ChannelSigner {
 ///
 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
 /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
-pub trait WriteableEcdsaChannelSigner: EcdsaChannelSigner + Writeable {}
+pub trait WriteableEcdsaChannelSigner: EcdsaChannelSigner + Writeable + Clone {}
 
 /// Specifies the recipient of an invoice.
 ///
diff --git a/lightning/src/chain/onchaintx.rs b/lightning/src/chain/onchaintx.rs
index 2d5c85cd4..69fb3eabd 100644
--- a/lightning/src/chain/onchaintx.rs
+++ b/lightning/src/chain/onchaintx.rs
@@ -56,7 +56,7 @@ const MAX_ALLOC_SIZE: usize = 64*1024;
 /// transaction causing it.
 ///
 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 struct OnchainEventEntry {
 	txid: Txid,
 	height: u32,
@@ -76,7 +76,7 @@ impl OnchainEventEntry {
 
 /// Events for claims the [`OnchainTxHandler`] has generated. Once the events are considered safe
 /// from a chain reorg, the [`OnchainTxHandler`] will act accordingly.
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 enum OnchainEvent {
 	/// A pending request has been claimed by a transaction spending the exact same set of outpoints
 	/// as the request. This claim can either be ours or from the counterparty. Once the claiming
@@ -223,6 +223,7 @@ type PackageID = [u8; 32];
 
 /// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
 /// do RBF bumping if possible.
+#[derive(Clone)]
 pub struct OnchainTxHandler<ChannelSigner: WriteableEcdsaChannelSigner> {
 	destination_script: Script,
 	holder_commitment: HolderCommitmentTransaction,
-- 
2.39.5