Return optional Transaction from register_output

[rust-lightning] / lightning / src / chain / mod.rs

diff --git a/lightning/src/chain/mod.rs b/lightning/src/chain/mod.rs
index c1fceec8c47171969397558db0ce62d11faf93ed..67ae5b347f9d94b029f93333fbb68dc6e23f9518 100644 (file)
--- a/lightning/src/chain/mod.rs
+++ b/lightning/src/chain/mod.rs
@@ -11,7 +11,7 @@
 
 use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::script::Script;
-use bitcoin::blockdata::transaction::TxOut;
+use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::hash_types::{BlockHash, Txid};
 
 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateErr, MonitorEvent};
@@ -25,8 +25,6 @@ pub mod transaction;
 pub mod keysinterface;
 
 /// An error when accessing the chain via [`Access`].
-///
-/// [`Access`]: trait.Access.html
 #[derive(Clone)]
 pub enum AccessError {
        /// The requested chain is unknown.
@@ -77,9 +75,9 @@ pub trait Listen {
 /// funds in the channel. See [`ChannelMonitorUpdateErr`] for more details about how to handle
 /// multiple instances.
 ///
-/// [`ChannelMonitor`]: channelmonitor/struct.ChannelMonitor.html
-/// [`ChannelMonitorUpdateErr`]: channelmonitor/enum.ChannelMonitorUpdateErr.html
-/// [`PermanentFailure`]: channelmonitor/enum.ChannelMonitorUpdateErr.html#variant.PermanentFailure
+/// [`ChannelMonitor`]: channelmonitor::ChannelMonitor
+/// [`ChannelMonitorUpdateErr`]: channelmonitor::ChannelMonitorUpdateErr
+/// [`PermanentFailure`]: channelmonitor::ChannelMonitorUpdateErr::PermanentFailure
 pub trait Watch<ChannelSigner: Sign>: Send + Sync {
        /// Watches a channel identified by `funding_txo` using `monitor`.
        ///
@@ -87,9 +85,9 @@ pub trait Watch<ChannelSigner: Sign>: Send + Sync {
        /// with any spends of outputs returned by [`get_outputs_to_watch`]. In practice, this means
        /// calling [`block_connected`] and [`block_disconnected`] on the monitor.
        ///
-       /// [`get_outputs_to_watch`]: channelmonitor/struct.ChannelMonitor.html#method.get_outputs_to_watch
-       /// [`block_connected`]: channelmonitor/struct.ChannelMonitor.html#method.block_connected
-       /// [`block_disconnected`]: channelmonitor/struct.ChannelMonitor.html#method.block_disconnected
+       /// [`get_outputs_to_watch`]: channelmonitor::ChannelMonitor::get_outputs_to_watch
+       /// [`block_connected`]: channelmonitor::ChannelMonitor::block_connected
+       /// [`block_disconnected`]: channelmonitor::ChannelMonitor::block_disconnected
        fn watch_channel(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
 
        /// Updates a channel identified by `funding_txo` by applying `update` to its monitor.
@@ -97,8 +95,8 @@ pub trait Watch<ChannelSigner: Sign>: Send + Sync {
        /// Implementations must call [`update_monitor`] with the given update. See
        /// [`ChannelMonitorUpdateErr`] for invariants around returning an error.
        ///
-       /// [`update_monitor`]: channelmonitor/struct.ChannelMonitor.html#method.update_monitor
-       /// [`ChannelMonitorUpdateErr`]: channelmonitor/enum.ChannelMonitorUpdateErr.html
+       /// [`update_monitor`]: channelmonitor::ChannelMonitor::update_monitor
+       /// [`ChannelMonitorUpdateErr`]: channelmonitor::ChannelMonitorUpdateErr
        fn update_channel(&self, funding_txo: OutPoint, update: ChannelMonitorUpdate) -> Result<(), ChannelMonitorUpdateErr>;
 
        /// Returns any monitor events since the last call. Subsequent calls must only return new
@@ -120,11 +118,10 @@ pub trait Watch<ChannelSigner: Sign>: Send + Sync {
 ///
 /// Note that use as part of a [`Watch`] implementation involves reentrancy. Therefore, the `Filter`
 /// should not block on I/O. Implementations should instead queue the newly monitored data to be
-/// processed later. Then, in order to block until the data has been processed, any `Watch`
+/// processed later. Then, in order to block until the data has been processed, any [`Watch`]
 /// invocation that has called the `Filter` must return [`TemporaryFailure`].
 ///
-/// [`Watch`]: trait.Watch.html
-/// [`TemporaryFailure`]: channelmonitor/enum.ChannelMonitorUpdateErr.html#variant.TemporaryFailure
+/// [`TemporaryFailure`]: channelmonitor::ChannelMonitorUpdateErr::TemporaryFailure
 /// [BIP 157]: https://github.com/bitcoin/bips/blob/master/bip-0157.mediawiki
 /// [BIP 158]: https://github.com/bitcoin/bips/blob/master/bip-0158.mediawiki
 pub trait Filter: Send + Sync {
@@ -134,7 +131,10 @@ pub trait Filter: Send + Sync {
 
        /// Registers interest in spends of a transaction output identified by `outpoint` having
        /// `script_pubkey` as the spending condition.
-       fn register_output(&self, outpoint: &OutPoint, script_pubkey: &Script);
+       ///
+       /// Optionally, returns any transaction dependent on the output. This is useful for Electrum
+       /// clients to facilitate registering in-block descendants.
+       fn register_output(&self, outpoint: &OutPoint, script_pubkey: &Script) -> Option<(usize, Transaction)>;
 }
 
 impl<T: Listen> Listen for std::ops::Deref<Target = T> {