//! # }
//! ```
//!
+//! # Note
+//!
+//! If persisting [`Scorer`], it must be restored using the same [`Time`] parameterization. Using a
+//! different type results in undefined behavior. Specifically, persisting when built with feature
+//! `no-std` and restoring without it, or vice versa, uses different types and thus is undefined.
+//!
//! [`find_route`]: crate::routing::router::find_route
use routing;
+use ln::msgs::DecodeError;
use routing::network_graph::NodeId;
use routing::router::RouteHop;
+use util::ser::{Readable, Writeable, Writer};
use prelude::*;
+use core::ops::Sub;
use core::time::Duration;
+use io::{self, Read};
/// [`routing::Score`] implementation that provides reasonable default behavior.
///
/// [`routing::Score`] implementation parameterized by [`Time`].
///
/// See [`Scorer`] for details.
+///
+/// # Note
+///
+/// Mixing [`Time`] types between serialization and deserialization results in undefined behavior.
pub struct ScorerUsingTime<T: Time> {
params: ScoringParameters,
// TODO: Remove entries of closed channels.
pub failure_penalty_half_life: Duration,
}
+impl_writeable_tlv_based!(ScoringParameters, {
+ (0, base_penalty_msat, required),
+ (2, failure_penalty_msat, required),
+ (4, failure_penalty_half_life, required),
+});
+
/// Accounting for penalties against a channel for failing to relay any payments.
///
/// Penalties decay over time, though accumulate as more failures occur.
}
/// A measurement of time.
-pub trait Time {
+pub trait Time: Sub<Duration, Output = Self> where Self: Sized {
/// Returns an instance corresponding to the current moment.
fn now() -> Self;
/// Returns the amount of time elapsed since `self` was created.
fn elapsed(&self) -> Duration;
+
+ /// Returns the amount of time passed since the beginning of [`Time`].
+ ///
+ /// Used during (de-)serialization.
+ fn duration_since_epoch() -> Duration;
}
impl<T: Time> ScorerUsingTime<T> {
self.params.base_penalty_msat + failure_penalty_msat
}
- fn payment_path_failed(&mut self, _path: &Vec<RouteHop>, short_channel_id: u64) {
+ fn payment_path_failed(&mut self, _path: &[&RouteHop], short_channel_id: u64) {
let failure_penalty_msat = self.params.failure_penalty_msat;
let half_life = self.params.failure_penalty_half_life;
self.channel_failures
std::time::Instant::now()
}
+ fn duration_since_epoch() -> Duration {
+ use std::time::SystemTime;
+ SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap()
+ }
+
fn elapsed(&self) -> Duration {
std::time::Instant::elapsed(self)
}
Self
}
+ fn duration_since_epoch() -> Duration {
+ Duration::from_secs(0)
+ }
+
fn elapsed(&self) -> Duration {
Duration::from_secs(0)
}
}
+
+impl Sub<Duration> for Eternity {
+ type Output = Self;
+
+ fn sub(self, _other: Duration) -> Self {
+ self
+ }
+}
+
+impl<T: Time> Writeable for ScorerUsingTime<T> {
+ #[inline]
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+ self.params.write(w)?;
+ self.channel_failures.write(w)?;
+ write_tlv_fields!(w, {});
+ Ok(())
+ }
+}
+
+impl<T: Time> Readable for ScorerUsingTime<T> {
+ #[inline]
+ fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let res = Ok(Self {
+ params: Readable::read(r)?,
+ channel_failures: Readable::read(r)?,
+ });
+ read_tlv_fields!(r, {});
+ res
+ }
+}
+
+impl<T: Time> Writeable for ChannelFailure<T> {
+ #[inline]
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+ let duration_since_epoch = T::duration_since_epoch() - self.last_failed.elapsed();
+ write_tlv_fields!(w, {
+ (0, self.undecayed_penalty_msat, required),
+ (2, duration_since_epoch, required),
+ });
+ Ok(())
+ }
+}
+
+impl<T: Time> Readable for ChannelFailure<T> {
+ #[inline]
+ fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let mut undecayed_penalty_msat = 0;
+ let mut duration_since_epoch = Duration::from_secs(0);
+ read_tlv_fields!(r, {
+ (0, undecayed_penalty_msat, required),
+ (2, duration_since_epoch, required),
+ });
+ Ok(Self {
+ undecayed_penalty_msat,
+ last_failed: T::now() - (T::duration_since_epoch() - duration_since_epoch),
+ })
+ }
+}