Integrate trackers into torrent event loop

DESIGN.md

@@ -146,8 +146,7 @@ Each tracker HTTP request runs asynchronously and is polled by the torrent
 event loop's select call.
 
 Periodically each torrent also sends progress updates to the tracker. The
-periodicity is kept low here to not take up bandwidth. It will be configurable
-in the future.
+periodicity is defined by the tracker, but it may be configurable in the future.
 
 ### Peer sessions
 

cratetorrent/src/engine.rs

@@ -8,6 +8,7 @@ use crate::{
  metainfo::Metainfo,
  storage_info::StorageInfo,
  torrent::Torrent,
+ tracker::Tracker,
  Bitfield, PeerId,
 };
 
@@ -115,6 +116,11 @@ async fn start_engine(
  return Ok(());
  };
 
+ let mut trackers = Vec::with_capacity(metainfo.trackers.len());
+ for tracker_url in metainfo.trackers.into_iter() {
+ trackers.push(Tracker::new(tracker_url));
+ }
+
  let own_pieces = mode.own_pieces(storage_info.piece_count);
  let mut torrent = Torrent::new(
  id,
@@ -123,10 +129,12 @@ async fn start_engine(
  info_hash,
  storage_info,
  own_pieces,
+ trackers,
  client_id,
+ listen_addr,
  );
  let seeds = mode.seeds();
- torrent.start(listen_addr, &seeds).await?;
+ torrent.start(&seeds).await?;
 
  // send a shutdown command to disk
  disk.shutdown()?;

cratetorrent/src/peer.rs

@@ -400,7 +400,7 @@ impl PeerSession {
  // keep-alive
 
  // update status
- self.state.tick();
+ self.state.tick(&self.torrent.stats);
 
  peer_info!(
  self,

cratetorrent/src/peer/state.rs

@@ -1,7 +1,11 @@
-use std::time::{Duration, Instant};
+use std::{
+ sync::atomic::Ordering,
+ time::{Duration, Instant},
+};
 
 use crate::{
- avg::SlidingDurationAvg, counter::Counter, Bitfield, PeerId, BLOCK_LEN,
+ avg::SlidingDurationAvg, counter::Counter, torrent::TorrentStats, Bitfield,
+ PeerId, BLOCK_LEN,
 };
 
 /// Holds and provides facilities to modify the state of a peer session.
@@ -183,7 +187,7 @@ impl SessionState {
  /// Updates various statistics and session state.
  ///
  /// This should be called every second.
- pub fn tick(&mut self) {
+ pub fn tick(&mut self, torrent_stats: &TorrentStats) {
  self.maybe_exit_slow_start();
 
  // NOTE: This has to be *after* `maybe_exit_slow_start` and *before*
@@ -199,9 +203,27 @@ impl SessionState {
  if !self.request_timed_out {
  self.update_target_request_queue_len();
  }
+
+ // copy over this round's transfer tally to the torrent's stats
+ torrent_stats.downloaded_protocol_count.fetch_add(
+ self.downloaded_protocol_counter.total(),
+ Ordering::Relaxed,
+ );
+ torrent_stats.uploaded_protocol_count.fetch_add(
+ self.uploaded_protocol_counter.total(),
+ Ordering::Relaxed,
+ );
+ torrent_stats.downloaded_payload_count.fetch_add(
+ self.downloaded_payload_counter.total(),
+ Ordering::Relaxed,
+ );
+ torrent_stats.uploaded_payload_count.fetch_add(
+ self.uploaded_payload_counter.total(),
+ Ordering::Relaxed,
+ );
  }
 
- /// Check if we need to exit slow start.
+ /// Checks if we need to exit slow start.
  ///
  /// We leave slow start if the download rate has not increased
  /// significantly since the last round.