ClientCirc: Move n_hops into a new Path type. (567995a7) · Commits · The Tor Project / Core / Arti

crates/tor-proto/src/circuit.rs

+9 −11

Original line number	Diff line number	Diff line
		@@ -41,6 +41,7 @@
		pub(crate) mod celltypes;
		pub(crate) mod halfcirc;
		mod halfstream;
		mod path;
		pub(crate) mod reactor;
		pub(crate) mod sendme;
		mod streammap;
		@@ -68,7 +69,6 @@ use futures::channel::{mpsc, oneshot};
		use crate::circuit::sendme::StreamRecvWindow;
		use futures::SinkExt;
		use std::net::IpAddr;
		use std::sync::atomic::{AtomicU8, Ordering};
		use std::sync::Arc;
		use tor_cell::relaycell::StreamId;
		// use std::time::Duration;
		@@ -88,7 +88,7 @@ pub const CIRCUIT_BUFFER_SIZE: usize = 128;
		/// they all actually communicate with the Reactor which contains the primary
		/// mutable state, and does the actual work.
		//
		// Effectively, this struct contains two Arcs: one for `hops` and one for
		// Effectively, this struct contains two Arcs: one for `path` and one for
		// `control` (which surely has something Arc-like in it). We cannot unify
		// these by putting a single Arc around the whole struct, and passing
		// an Arc strong reference to the `Reactor`, because then `control` would
		@@ -100,10 +100,8 @@ pub const CIRCUIT_BUFFER_SIZE: usize = 128;
		// two atomic refcount changes/checks. Wrapping it in another Arc would
		// be overkill.
		pub struct ClientCirc {
		/// Number of hops on this circuit.
		///
		/// This value is incremented after the circuit successfully completes extending to a new hop.
		hops: Arc<AtomicU8>,
		/// Information about this circuit's path.
		path: Arc<path::Path>,
		/// A unique identifier for this circuit.
		unique_id: UniqId,
		/// Channel to send control messages to the reactor.
		@@ -239,7 +237,7 @@ impl ClientCirc {
		// TODO: Possibly this should take a hop, rather than just
		// assuming it's the last hop.

		let num_hops = self.hops.load(Ordering::SeqCst);
		let num_hops = self.path.n_hops();
		if num_hops == 0 {
		return Err(Error::from(internal!(
		"Can't begin a stream at the 0th hop"
		@@ -408,7 +406,7 @@ impl ClientCirc {

		#[cfg(test)]
		pub fn n_hops(&self) -> u8 {
		self.hops.load(Ordering::SeqCst)
		self.path.n_hops()
		}
		}

		@@ -427,7 +425,7 @@ impl PendingClientCirc {
		) -> (PendingClientCirc, reactor::Reactor) {
		let crypto_out = OutboundClientCrypt::new();
		let (control_tx, control_rx) = mpsc::unbounded();
		let num_hops = Arc::new(AtomicU8::new(0));
		let path = Arc::new(path::Path::default());

		let reactor = Reactor {
		control: control_rx,
		@@ -440,11 +438,11 @@ impl PendingClientCirc {
		channel_id: id,
		crypto_out,
		meta_handler: None,
		num_hops: Arc::clone(&num_hops),
		path: Arc::clone(&path),
		};

		let circuit = ClientCirc {
		hops: num_hops,
		path,
		unique_id,
		control: control_tx,
		#[cfg(test)]

crates/tor-proto/src/circuit/path.rs

0 → 100644

+24 −0

Original line number	Diff line number	Diff line
		//! Tracking for the path of a client circuit.

		use std::sync::atomic::{AtomicU8, Ordering};

		/// Helper struct that shares information
		#[derive(Debug, Default)]
		pub(super) struct Path {
		/// Number of hops on this circuit.
		///
		/// This value is incremented after the circuit successfully completes extending to a new hop.
		n_hops: AtomicU8,
		}

		impl Path {
		/// Return the number of hops in this path
		pub(super) fn n_hops(&self) -> u8 {
		self.n_hops.load(Ordering::SeqCst)
		}

		/// Add 1 to the number of hops in this path.
		pub(super) fn inc_hops(&self) {
		self.n_hops.fetch_add(1, Ordering::SeqCst);
		}
		}

crates/tor-proto/src/circuit/reactor.rs

+3 −3

Original line number	Diff line number	Diff line
		@@ -24,11 +24,11 @@ use futures::Sink;
		use futures::Stream;
		use tor_error::internal;

		use std::sync::atomic::{AtomicU8, Ordering};
		use std::sync::Arc;
		use std::task::{Context, Poll};

		use crate::channel::Channel;
		use crate::circuit::path;
		#[cfg(test)]
		use crate::circuit::sendme::CircTag;
		use crate::circuit::sendme::StreamSendWindow;
		@@ -446,7 +446,7 @@ pub struct Reactor {
		/// List of hops state objects used by the reactor
		pub(super) hops: Vec<CircHop>,
		/// Shared atomic for the number of hops this circuit has.
		pub(super) num_hops: Arc<AtomicU8>,
		pub(super) path: Arc<path::Path>,
		/// An identifier for logging about this reactor's circuit.
		pub(super) unique_id: UniqId,
		/// This circuit's identifier on the upstream channel.
		@@ -811,7 +811,7 @@ impl Reactor {
		self.hops.push(hop);
		self.crypto_in.add_layer(rev);
		self.crypto_out.add_layer(fwd);
		self.num_hops.fetch_add(1, Ordering::SeqCst);
		self.path.inc_hops();
		}

		/// Handle a RELAY cell on this circuit with stream ID 0.