//! Includes traits for monitoring and receiving notifications of new blocks and block
//! disconnections, transaction broadcasting, and feerate information requests.
-use bitcoin::blockdata::block::{Block, BlockHeader};
use bitcoin::blockdata::transaction::Transaction;
-use bitcoin::blockdata::script::Script;
-use bitcoin::hash_types::Txid;
-
-use std::sync::{Mutex, Arc};
-use std::collections::HashSet;
-use std::ops::Deref;
-use std::marker::PhantomData;
-use std::ptr;
/// An interface to send a transaction to the Bitcoin network.
-pub trait BroadcasterInterface: Sync + Send {
+pub trait BroadcasterInterface {
/// Sends a transaction out to (hopefully) be mined.
fn broadcast_transaction(&self, tx: &Transaction);
}
-/// A trait indicating a desire to listen for events from the chain
-pub trait ChainListener: Sync + Send {
- /// Notifies a listener that a block was connected. Transactions may be filtered and are given
- /// paired with their position within the block.
- fn block_connected(&self, header: &BlockHeader, txdata: &[(usize, &Transaction)], height: u32);
-
- /// Notifies a listener that a block was disconnected.
- /// Unlike block_connected, this *must* never be called twice for the same disconnect event.
- /// Height must be the one of the block which was disconnected (not new height of the best chain)
- fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32);
-}
-
/// An enum that represents the speed at which we want a transaction to confirm used for feerate
/// estimation.
+#[derive(Clone, Copy, PartialEq, Eq)]
pub enum ConfirmationTarget {
/// We are happy with this transaction confirming slowly when feerate drops some.
Background,
/// horizons.
///
/// Note that all of the functions implemented here *must* be reentrant-safe (obviously - they're
-/// called from inside the library in response to ChainListener events, P2P events, or timer
-/// events).
-pub trait FeeEstimator: Sync + Send {
+/// called from inside the library in response to chain events, P2P events, or timer events).
+pub trait FeeEstimator {
/// Gets estimated satoshis of fee required per 1000 Weight-Units.
///
/// Must be no smaller than 253 (ie 1 satoshi-per-byte rounded up to ensure later round-downs
/// Minimum relay fee as required by bitcoin network mempool policy.
pub const MIN_RELAY_FEE_SAT_PER_1000_WEIGHT: u64 = 4000;
-
-/// Utility for tracking registered txn/outpoints and checking for matches
-#[cfg_attr(test, derive(PartialEq))]
-pub struct ChainWatchedUtil {
- watch_all: bool,
-
- // We are more conservative in matching during testing to ensure everything matches *exactly*,
- // even though during normal runtime we take more optimized match approaches...
- #[cfg(test)]
- watched_txn: HashSet<(Txid, Script)>,
- #[cfg(not(test))]
- watched_txn: HashSet<Script>,
-
- watched_outpoints: HashSet<(Txid, u32)>,
-}
-
-impl ChainWatchedUtil {
- /// Constructs an empty (watches nothing) ChainWatchedUtil
- pub fn new() -> Self {
- Self {
- watch_all: false,
- watched_txn: HashSet::new(),
- watched_outpoints: HashSet::new(),
- }
- }
-
- /// Registers a tx for monitoring, returning true if it was a new tx and false if we'd already
- /// been watching for it.
- pub fn register_tx(&mut self, txid: &Txid, script_pub_key: &Script) -> bool {
- if self.watch_all { return false; }
- #[cfg(test)]
- {
- self.watched_txn.insert((txid.clone(), script_pub_key.clone()))
- }
- #[cfg(not(test))]
- {
- let _tx_unused = txid; // It's used in cfg(test), though
- self.watched_txn.insert(script_pub_key.clone())
- }
- }
-
- /// Registers an outpoint for monitoring, returning true if it was a new outpoint and false if
- /// we'd already been watching for it
- pub fn register_outpoint(&mut self, outpoint: (Txid, u32), _script_pub_key: &Script) -> bool {
- if self.watch_all { return false; }
- self.watched_outpoints.insert(outpoint)
- }
-
- /// Sets us to match all transactions, returning true if this is a new setting and false if
- /// we'd already been set to match everything.
- pub fn watch_all(&mut self) -> bool {
- if self.watch_all { return false; }
- self.watch_all = true;
- true
- }
-
- /// Checks if a given transaction matches the current filter.
- pub fn does_match_tx(&self, tx: &Transaction) -> bool {
- if self.watch_all {
- return true;
- }
- for out in tx.output.iter() {
- #[cfg(test)]
- for &(ref txid, ref script) in self.watched_txn.iter() {
- if *script == out.script_pubkey {
- if tx.txid() == *txid {
- return true;
- }
- }
- }
- #[cfg(not(test))]
- for script in self.watched_txn.iter() {
- if *script == out.script_pubkey {
- return true;
- }
- }
- }
- for input in tx.input.iter() {
- for outpoint in self.watched_outpoints.iter() {
- let &(outpoint_hash, outpoint_index) = outpoint;
- if outpoint_hash == input.previous_output.txid && outpoint_index == input.previous_output.vout {
- return true;
- }
- }
- }
- false
- }
-}
-
-/// BlockNotifierArc is useful when you need a BlockNotifier that points to ChainListeners with
-/// static lifetimes, e.g. when you're using lightning-net-tokio (since tokio::spawn requires
-/// parameters with static lifetimes). Other times you can afford a reference, which is more
-/// efficient, in which case BlockNotifierRef is a more appropriate type. Defining these type
-/// aliases prevents issues such as overly long function definitions.
-///
-/// (C-not exported) as we let clients handle any reference counting they need to do
-pub type BlockNotifierArc = Arc<BlockNotifier<'static, Arc<ChainListener>>>;
-
-/// BlockNotifierRef is useful when you want a BlockNotifier that points to ChainListeners
-/// with nonstatic lifetimes. This is useful for when static lifetimes are not needed. Nonstatic
-/// lifetimes are more efficient but less flexible, and should be used by default unless static
-/// lifetimes are required, e.g. when you're using lightning-net-tokio (since tokio::spawn
-/// requires parameters with static lifetimes), in which case BlockNotifierArc is a more
-/// appropriate type. Defining these type aliases for common usages prevents issues such as
-/// overly long function definitions.
-pub type BlockNotifierRef<'a> = BlockNotifier<'a, &'a ChainListener>;
-
-/// Utility for notifying listeners when blocks are connected or disconnected.
-///
-/// Rather than using a plain BlockNotifier, it is preferable to use either a BlockNotifierArc
-/// or a BlockNotifierRef for conciseness. See their documentation for more details, but essentially
-/// you should default to using a BlockNotifierRef, and use a BlockNotifierArc instead when you
-/// require ChainListeners with static lifetimes, such as when you're using lightning-net-tokio.
-pub struct BlockNotifier<'a, CL: Deref + 'a>
- where CL::Target: ChainListener + 'a {
- listeners: Mutex<Vec<CL>>,
- phantom: PhantomData<&'a ()>,
-}
-
-impl<'a, CL: Deref + 'a> BlockNotifier<'a, CL>
- where CL::Target: ChainListener + 'a {
- /// Constructs a new BlockNotifier without any listeners.
- pub fn new() -> BlockNotifier<'a, CL> {
- BlockNotifier {
- listeners: Mutex::new(Vec::new()),
- phantom: PhantomData,
- }
- }
-
- /// Register the given listener to receive events.
- pub fn register_listener(&self, listener: CL) {
- let mut vec = self.listeners.lock().unwrap();
- vec.push(listener);
- }
- /// Unregister the given listener to no longer
- /// receive events.
- ///
- /// If the same listener is registered multiple times, unregistering
- /// will remove ALL occurrences of that listener. Comparison is done using
- /// the pointer returned by the Deref trait implementation.
- ///
- /// (C-not exported) because the equality check would always fail
- pub fn unregister_listener(&self, listener: CL) {
- let mut vec = self.listeners.lock().unwrap();
- // item is a ref to an abstract thing that dereferences to a ChainListener,
- // so dereference it twice to get the ChainListener itself
- vec.retain(|item | !ptr::eq(&(**item), &(*listener)));
- }
-
- /// Notify listeners that a block was connected.
- pub fn block_connected(&self, block: &Block, height: u32) {
- let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
- let listeners = self.listeners.lock().unwrap();
- for listener in listeners.iter() {
- listener.block_connected(&block.header, &txdata, height);
- }
- }
-
- /// Notify listeners that a block was disconnected.
- pub fn block_disconnected(&self, header: &BlockHeader, disconnected_height: u32) {
- let listeners = self.listeners.lock().unwrap();
- for listener in listeners.iter() {
- listener.block_disconnected(&header, disconnected_height);
- }
- }
-}
-
-#[cfg(test)]
-mod tests {
- use bitcoin::blockdata::block::BlockHeader;
- use bitcoin::blockdata::transaction::Transaction;
- use super::{BlockNotifier, ChainListener};
- use std::ptr;
-
- struct TestChainListener(u8);
-
- impl ChainListener for TestChainListener {
- fn block_connected(&self, _header: &BlockHeader, _txdata: &[(usize, &Transaction)], _height: u32) {}
- fn block_disconnected(&self, _header: &BlockHeader, _disconnected_height: u32) {}
- }
-
- #[test]
- fn register_listener_test() {
- let block_notifier = BlockNotifier::new();
- assert_eq!(block_notifier.listeners.lock().unwrap().len(), 0);
- let listener = &TestChainListener(0);
- block_notifier.register_listener(listener as &ChainListener);
- let vec = block_notifier.listeners.lock().unwrap();
- assert_eq!(vec.len(), 1);
- let item = vec.first().unwrap();
- assert!(ptr::eq(&(**item), listener));
- }
-
- #[test]
- fn unregister_single_listener_test() {
- let block_notifier = BlockNotifier::new();
- let listener1 = &TestChainListener(1);
- let listener2 = &TestChainListener(2);
- block_notifier.register_listener(listener1 as &ChainListener);
- block_notifier.register_listener(listener2 as &ChainListener);
- let vec = block_notifier.listeners.lock().unwrap();
- assert_eq!(vec.len(), 2);
- drop(vec);
- block_notifier.unregister_listener(listener1);
- let vec = block_notifier.listeners.lock().unwrap();
- assert_eq!(vec.len(), 1);
- let item = vec.first().unwrap();
- assert!(ptr::eq(&(**item), listener2));
- }
-
- #[test]
- fn unregister_multiple_of_the_same_listeners_test() {
- let block_notifier = BlockNotifier::new();
- let listener1 = &TestChainListener(1);
- let listener2 = &TestChainListener(2);
- block_notifier.register_listener(listener1 as &ChainListener);
- block_notifier.register_listener(listener1 as &ChainListener);
- block_notifier.register_listener(listener2 as &ChainListener);
- let vec = block_notifier.listeners.lock().unwrap();
- assert_eq!(vec.len(), 3);
- drop(vec);
- block_notifier.unregister_listener(listener1);
- let vec = block_notifier.listeners.lock().unwrap();
- assert_eq!(vec.len(), 1);
- let item = vec.first().unwrap();
- assert!(ptr::eq(&(**item), listener2));
- }
-}
projects / rust-lightning / blobdiff