1695 lines
61 KiB
Rust
1695 lines
61 KiB
Rust
// The main logic of rqbit is here - connecting to peers, reading and writing messages
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// to them, tracking peer state etc.
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//
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// ## Architecture
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// There are many tasks cooperating to download the torrent. Tasks communicate both with message passing
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// and shared memory.
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//
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// ### Shared locked state
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// Shared state is access by almost all actors through RwLocks.
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//
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// There's one source of truth (TorrentStateLocked) for which chunks we have, need, and what peers are we waiting them from.
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//
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// Peer states that are important to the outsiders (tasks other than manage_peer) are in a sharded hash-map (DashMap)
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//
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// ### Tasks (actors)
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// Peer adder task:
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// - spawns new peers as they become known. It pulls them from a queue. The queue is filled in by DHT and torrent trackers.
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// Also gets updated when peers are reconnecting after errors.
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//
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// Each peer has one main task "manage_peer". It's composed of 2 futures running as one task through tokio::select:
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// - "manage_peer" - this talks to the peer over network and calls callbacks on PeerHandler. The callbacks are not async,
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// and are supposed to finish quickly (apart from writing to disk, which is accounted for as "spawn_blocking").
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// - "peer_chunk_requester" - this continuously sends requests for chunks to the peer.
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// it may steal chunks/pieces from other peers.
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//
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// ## Peer lifecycle
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// State transitions:
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// - queued (initial state) -> connected
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// - connected -> live
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// - ANY STATE -> dead (on error)
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// - ANY STATE -> not_needed (when we don't need to talk to the peer anymore)
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//
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// When the peer dies, it's rescheduled with exponential backoff.
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//
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// > NOTE: deadlock notice:
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// > peers and stateLocked are behind 2 different locks.
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// > if you lock them in different order, this may deadlock.
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// >
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// > so don't lock them both at the same time at all, or at the worst lock them in the
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// > same order (peers one first, then the global one).
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pub mod peer;
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pub mod peers;
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pub mod stats;
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use std::{
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collections::{HashMap, HashSet},
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net::SocketAddr,
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sync::{
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atomic::{AtomicBool, AtomicU64, Ordering},
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Arc,
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},
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time::{Duration, Instant},
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};
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use anyhow::{bail, Context};
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use backoff::backoff::Backoff;
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use buffers::{ByteBuf, ByteBufOwned};
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use clone_to_owned::CloneToOwned;
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use librqbit_core::{
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constants::CHUNK_SIZE,
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hash_id::Id20,
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lengths::{ChunkInfo, Lengths, ValidPieceIndex},
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spawn_utils::spawn_with_cancel,
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speed_estimator::SpeedEstimator,
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torrent_metainfo::TorrentMetaV1Info,
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};
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use parking_lot::{RwLock, RwLockReadGuard, RwLockWriteGuard};
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use peer_binary_protocol::{
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extended::{
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handshake::{ExtendedHandshake, YourIP},
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ut_metadata::UtMetadata,
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ut_pex::UtPex,
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ExtendedMessage,
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},
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Handshake, Message, MessageOwned, Piece, Request,
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};
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use peers::stats::atomic::AggregatePeerStatsAtomic;
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use tokio::sync::{
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mpsc::{unbounded_channel, UnboundedReceiver, UnboundedSender},
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Notify, OwnedSemaphorePermit, Semaphore,
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};
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use tokio_util::sync::CancellationToken;
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use tracing::{debug, error, error_span, info, trace, warn, Instrument};
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use crate::{
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chunk_tracker::{ChunkMarkingResult, ChunkTracker, HaveNeededSelected},
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file_ops::FileOps,
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peer_connection::{
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PeerConnection, PeerConnectionHandler, PeerConnectionOptions, WriterRequest,
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},
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session::CheckedIncomingConnection,
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session_stats::atomic::AtomicSessionStats,
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torrent_state::{peer::Peer, utils::atomic_inc},
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type_aliases::{DiskWorkQueueSender, FilePriorities, FileStorage, PeerHandle, BF},
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};
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use self::{
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peer::{
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stats::{
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atomic::PeerCountersAtomic as AtomicPeerCounters,
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snapshot::{PeerStatsFilter, PeerStatsSnapshot},
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},
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PeerRx, PeerState, PeerTx,
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},
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peers::PeerStates,
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stats::{atomic::AtomicStats, snapshot::StatsSnapshot},
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};
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use super::{
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paused::TorrentStatePaused,
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streaming::TorrentStreams,
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utils::{timeit, TimedExistence},
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ManagedTorrentShared,
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};
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#[derive(Debug)]
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struct InflightPiece {
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peer: PeerHandle,
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started: Instant,
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}
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fn make_piece_bitfield(lengths: &Lengths) -> BF {
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BF::from_boxed_slice(vec![0; lengths.piece_bitfield_bytes()].into_boxed_slice())
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}
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pub(crate) struct TorrentStateLocked {
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// What chunks we have and need.
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// If this is None, the torrent was paused, and this live state is useless, and needs to be dropped.
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pub(crate) chunks: Option<ChunkTracker>,
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// The sorted file list in which order to download them.
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file_priorities: FilePriorities,
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// At a moment in time, we are expecting a piece from only one peer.
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// inflight_pieces stores this information.
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inflight_pieces: HashMap<ValidPieceIndex, InflightPiece>,
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// If this is None, then it was already used
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fatal_errors_tx: Option<tokio::sync::oneshot::Sender<anyhow::Error>>,
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unflushed_bitv_bytes: u64,
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}
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impl TorrentStateLocked {
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pub(crate) fn get_chunks(&self) -> anyhow::Result<&ChunkTracker> {
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self.chunks
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.as_ref()
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.context("chunk tracker empty, torrent was paused")
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}
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pub(crate) fn get_chunks_mut(&mut self) -> anyhow::Result<&mut ChunkTracker> {
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self.chunks
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.as_mut()
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.context("chunk tracker empty, torrent was paused")
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}
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fn try_flush_bitv(&mut self) {
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if self.unflushed_bitv_bytes == 0 {
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return;
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}
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trace!("trying to flush bitfield");
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if let Some(Err(e)) = self
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.chunks
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.as_mut()
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.map(|ct| ct.get_have_pieces_mut().flush())
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{
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warn!(error=?e, "error flushing bitfield");
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} else {
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trace!("flushed bitfield");
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self.unflushed_bitv_bytes = 0;
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}
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}
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}
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const FLUSH_BITV_EVERY_BYTES: u64 = 16 * 1024 * 1024;
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pub struct TorrentStateLive {
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peers: PeerStates,
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torrent: Arc<ManagedTorrentShared>,
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locked: RwLock<TorrentStateLocked>,
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pub(crate) files: FileStorage,
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per_piece_locks: Vec<RwLock<()>>,
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stats: AtomicStats,
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lengths: Lengths,
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// Limits how many active (occupying network resources) peers there are at a moment in time.
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peer_semaphore: Arc<Semaphore>,
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// The queue for peer manager to connect to them.
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peer_queue_tx: UnboundedSender<SocketAddr>,
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finished_notify: Notify,
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new_pieces_notify: Notify,
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down_speed_estimator: SpeedEstimator,
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up_speed_estimator: SpeedEstimator,
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cancellation_token: CancellationToken,
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session_stats: Arc<AtomicSessionStats>,
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pub(crate) streams: Arc<TorrentStreams>,
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have_broadcast_tx: tokio::sync::broadcast::Sender<ValidPieceIndex>,
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}
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impl TorrentStateLive {
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pub(crate) fn new(
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paused: TorrentStatePaused,
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fatal_errors_tx: tokio::sync::oneshot::Sender<anyhow::Error>,
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cancellation_token: CancellationToken,
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) -> anyhow::Result<Arc<Self>> {
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let (peer_queue_tx, peer_queue_rx) = unbounded_channel();
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let session = paused
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.shared
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.session
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.upgrade()
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.context("session is dead, cannot start torrent")?;
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let session_stats = session.stats.atomic.clone();
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let down_speed_estimator = SpeedEstimator::default();
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let up_speed_estimator = SpeedEstimator::default();
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let have_bytes = paused.chunk_tracker.get_hns().have_bytes;
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let lengths = *paused.chunk_tracker.get_lengths();
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// TODO: make it configurable
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let file_priorities = {
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let mut pri = (0..paused.shared.file_infos.len()).collect::<Vec<usize>>();
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// sort by filename, cause many torrents have random sort order.
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pri.sort_unstable_by_key(|id| {
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paused
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.shared
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.file_infos
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.get(*id)
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.map(|fi| fi.relative_filename.as_path())
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});
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pri
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};
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let (have_broadcast_tx, _) = tokio::sync::broadcast::channel(128);
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let state = Arc::new(TorrentStateLive {
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torrent: paused.shared.clone(),
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peers: PeerStates {
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session_stats: session_stats.clone(),
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stats: Default::default(),
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states: Default::default(),
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},
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locked: RwLock::new(TorrentStateLocked {
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chunks: Some(paused.chunk_tracker),
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// TODO: move under per_piece_locks?
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inflight_pieces: Default::default(),
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file_priorities,
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fatal_errors_tx: Some(fatal_errors_tx),
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unflushed_bitv_bytes: 0,
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}),
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files: paused.files,
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stats: AtomicStats {
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have_bytes: AtomicU64::new(have_bytes),
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..Default::default()
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},
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lengths,
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peer_semaphore: Arc::new(Semaphore::new(128)),
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new_pieces_notify: Notify::new(),
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peer_queue_tx,
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finished_notify: Notify::new(),
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down_speed_estimator,
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up_speed_estimator,
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cancellation_token,
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have_broadcast_tx,
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session_stats,
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streams: paused.streams,
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per_piece_locks: (0..lengths.total_pieces())
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.map(|_| RwLock::new(()))
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.collect(),
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});
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state.spawn(
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error_span!(parent: state.torrent.span.clone(), "speed_estimator_updater"),
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{
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let state = Arc::downgrade(&state);
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async move {
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loop {
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let state = match state.upgrade() {
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Some(state) => state,
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None => return Ok(()),
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};
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let now = Instant::now();
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let stats = state.stats_snapshot();
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let fetched = stats.fetched_bytes;
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let remaining = state.locked.read().get_chunks()?.get_remaining_bytes();
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state
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.down_speed_estimator
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.add_snapshot(fetched, Some(remaining), now);
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state
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.up_speed_estimator
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.add_snapshot(stats.uploaded_bytes, None, now);
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tokio::time::sleep(Duration::from_secs(1)).await;
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}
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}
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},
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);
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state.spawn(
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error_span!(parent: state.torrent.span.clone(), "peer_adder"),
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state.clone().task_peer_adder(peer_queue_rx),
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);
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Ok(state)
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}
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#[track_caller]
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pub(crate) fn spawn(
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&self,
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span: tracing::Span,
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fut: impl std::future::Future<Output = anyhow::Result<()>> + Send + 'static,
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) {
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spawn_with_cancel(span, self.cancellation_token.clone(), fut);
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}
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fn peer_stats(&self) -> [&AggregatePeerStatsAtomic; 2] {
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[&self.peers.stats, &self.peers.session_stats.peers]
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}
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pub fn down_speed_estimator(&self) -> &SpeedEstimator {
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&self.down_speed_estimator
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}
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pub fn up_speed_estimator(&self) -> &SpeedEstimator {
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&self.up_speed_estimator
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}
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fn disk_work_tx(&self) -> Option<&DiskWorkQueueSender> {
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self.torrent.options.disk_write_queue.as_ref()
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}
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pub(crate) fn add_incoming_peer(
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self: &Arc<Self>,
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checked_peer: CheckedIncomingConnection,
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) -> anyhow::Result<()> {
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use dashmap::mapref::entry::Entry;
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let (tx, rx) = unbounded_channel();
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let permit = match self.peer_semaphore.clone().try_acquire_owned() {
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Ok(permit) => permit,
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Err(_) => {
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debug!("limit of live peers reached, dropping incoming peer");
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self.peers.with_peer(checked_peer.addr, |p| {
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atomic_inc(&p.stats.counters.incoming_connections);
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});
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return Ok(());
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}
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};
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let counters = match self.peers.states.entry(checked_peer.addr) {
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Entry::Occupied(mut occ) => {
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let peer = occ.get_mut();
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peer.state
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.incoming_connection(
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Id20::new(checked_peer.handshake.peer_id),
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tx.clone(),
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&self.peer_stats(),
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)
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.context("peer already existed")?;
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peer.stats.counters.clone()
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}
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Entry::Vacant(vac) => {
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atomic_inc(&self.peers.stats.seen);
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let peer = Peer::new_live_for_incoming_connection(
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Id20::new(checked_peer.handshake.peer_id),
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tx.clone(),
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&self.peer_stats(),
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);
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let counters = peer.stats.counters.clone();
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vac.insert(peer);
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counters
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}
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};
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atomic_inc(&counters.incoming_connections);
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self.spawn(
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error_span!(
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parent: self.torrent.span.clone(),
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"manage_incoming_peer",
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addr = %checked_peer.addr
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),
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aframe!(self
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.clone()
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.task_manage_incoming_peer(checked_peer, counters, tx, rx, permit)),
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);
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Ok(())
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}
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async fn task_manage_incoming_peer(
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self: Arc<Self>,
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checked_peer: CheckedIncomingConnection,
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counters: Arc<AtomicPeerCounters>,
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tx: PeerTx,
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rx: PeerRx,
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permit: OwnedSemaphorePermit,
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) -> anyhow::Result<()> {
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// TODO: bump counters for incoming
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let handler = PeerHandler {
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addr: checked_peer.addr,
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on_bitfield_notify: Default::default(),
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unchoke_notify: Default::default(),
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locked: RwLock::new(PeerHandlerLocked { i_am_choked: true }),
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requests_sem: Semaphore::new(0),
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state: self.clone(),
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tx,
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counters,
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first_message_received: AtomicBool::new(false),
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};
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let options = PeerConnectionOptions {
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connect_timeout: self.torrent.options.peer_connect_timeout,
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read_write_timeout: self.torrent.options.peer_read_write_timeout,
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..Default::default()
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};
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let peer_connection = PeerConnection::new(
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checked_peer.addr,
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self.torrent.info_hash,
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self.torrent.peer_id,
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&handler,
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Some(options),
|
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self.torrent.spawner,
|
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self.torrent.connector.clone(),
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);
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let requester = handler.task_peer_chunk_requester();
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let res = tokio::select! {
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r = requester => {r}
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r = peer_connection.manage_peer_incoming(
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rx,
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checked_peer.read_buf,
|
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checked_peer.handshake,
|
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checked_peer.stream,
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self.have_broadcast_tx.subscribe()
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) => {r}
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};
|
|
|
|
match res {
|
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// We disconnected the peer ourselves as we don't need it
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Ok(()) => {
|
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handler.on_peer_died(None)?;
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}
|
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Err(e) => {
|
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debug!("error managing peer: {:#}", e);
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handler.on_peer_died(Some(e))?;
|
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}
|
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};
|
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drop(permit);
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Ok(())
|
|
}
|
|
|
|
async fn task_manage_outgoing_peer(
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self: Arc<Self>,
|
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addr: SocketAddr,
|
|
permit: OwnedSemaphorePermit,
|
|
) -> anyhow::Result<()> {
|
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let state = self;
|
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let (rx, tx) = state.peers.mark_peer_connecting(addr)?;
|
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let counters = state
|
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.peers
|
|
.with_peer(addr, |p| p.stats.counters.clone())
|
|
.context("bug: peer not found")?;
|
|
|
|
let handler = PeerHandler {
|
|
addr,
|
|
on_bitfield_notify: Default::default(),
|
|
unchoke_notify: Default::default(),
|
|
locked: RwLock::new(PeerHandlerLocked { i_am_choked: true }),
|
|
requests_sem: Semaphore::new(0),
|
|
state: state.clone(),
|
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tx,
|
|
counters,
|
|
first_message_received: AtomicBool::new(false),
|
|
};
|
|
let options = PeerConnectionOptions {
|
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connect_timeout: state.torrent.options.peer_connect_timeout,
|
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read_write_timeout: state.torrent.options.peer_read_write_timeout,
|
|
..Default::default()
|
|
};
|
|
let peer_connection = PeerConnection::new(
|
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addr,
|
|
state.torrent.info_hash,
|
|
state.torrent.peer_id,
|
|
&handler,
|
|
Some(options),
|
|
state.torrent.spawner,
|
|
state.torrent.connector.clone(),
|
|
);
|
|
let requester = aframe!(handler
|
|
.task_peer_chunk_requester()
|
|
.instrument(error_span!("chunk_requester")));
|
|
let conn_manager = aframe!(peer_connection
|
|
.manage_peer_outgoing(rx, state.have_broadcast_tx.subscribe())
|
|
.instrument(error_span!("peer_connection")));
|
|
|
|
handler
|
|
.counters
|
|
.outgoing_connection_attempts
|
|
.fetch_add(1, Ordering::Relaxed);
|
|
let res = tokio::select! {
|
|
r = requester => {r}
|
|
r = conn_manager => {r}
|
|
};
|
|
|
|
match res {
|
|
// We disconnected the peer ourselves as we don't need it
|
|
Ok(()) => {
|
|
handler.on_peer_died(None)?;
|
|
}
|
|
Err(e) => {
|
|
debug!("error managing peer: {:#}", e);
|
|
handler.on_peer_died(Some(e))?;
|
|
}
|
|
}
|
|
drop(permit);
|
|
Ok::<_, anyhow::Error>(())
|
|
}
|
|
|
|
async fn task_peer_adder(
|
|
self: Arc<Self>,
|
|
mut peer_queue_rx: UnboundedReceiver<SocketAddr>,
|
|
) -> anyhow::Result<()> {
|
|
let state = self;
|
|
loop {
|
|
let addr = peer_queue_rx.recv().await.context("torrent closed")?;
|
|
if state.is_finished_and_no_active_streams() {
|
|
debug!("ignoring peer {} as we are finished", addr);
|
|
state.peers.mark_peer_not_needed(addr);
|
|
continue;
|
|
}
|
|
|
|
let permit = state.peer_semaphore.clone().acquire_owned().await?;
|
|
state.spawn(
|
|
error_span!(parent: state.torrent.span.clone(), "manage_peer", peer = addr.to_string()),
|
|
aframe!(state.clone().task_manage_outgoing_peer(addr, permit)),
|
|
);
|
|
}
|
|
}
|
|
|
|
pub fn torrent(&self) -> &ManagedTorrentShared {
|
|
&self.torrent
|
|
}
|
|
|
|
pub fn info(&self) -> &TorrentMetaV1Info<ByteBufOwned> {
|
|
&self.torrent.info
|
|
}
|
|
pub fn info_hash(&self) -> Id20 {
|
|
self.torrent.info_hash
|
|
}
|
|
pub fn peer_id(&self) -> Id20 {
|
|
self.torrent.peer_id
|
|
}
|
|
pub(crate) fn file_ops(&self) -> FileOps<'_> {
|
|
FileOps::new(
|
|
&self.torrent.info,
|
|
&*self.files,
|
|
&self.torrent().file_infos,
|
|
&self.lengths,
|
|
)
|
|
}
|
|
|
|
pub(crate) fn lock_read(
|
|
&self,
|
|
reason: &'static str,
|
|
) -> TimedExistence<RwLockReadGuard<TorrentStateLocked>> {
|
|
TimedExistence::new(timeit(reason, || self.locked.read()), reason)
|
|
}
|
|
pub(crate) fn lock_write(
|
|
&self,
|
|
reason: &'static str,
|
|
) -> TimedExistence<RwLockWriteGuard<TorrentStateLocked>> {
|
|
TimedExistence::new(timeit(reason, || self.locked.write()), reason)
|
|
}
|
|
|
|
fn set_peer_live<B>(&self, handle: PeerHandle, h: Handshake<B>) {
|
|
self.peers.with_peer_mut(handle, "set_peer_live", |p| {
|
|
p.state
|
|
.connecting_to_live(Id20::new(h.peer_id), &self.peer_stats());
|
|
});
|
|
}
|
|
|
|
pub fn get_uploaded_bytes(&self) -> u64 {
|
|
self.stats.uploaded_bytes.load(Ordering::Relaxed)
|
|
}
|
|
pub fn get_downloaded_bytes(&self) -> u64 {
|
|
self.stats
|
|
.downloaded_and_checked_bytes
|
|
.load(Ordering::Acquire)
|
|
}
|
|
|
|
pub fn get_approx_have_bytes(&self) -> u64 {
|
|
self.stats.have_bytes.load(Ordering::Relaxed)
|
|
}
|
|
|
|
pub fn get_hns(&self) -> Option<HaveNeededSelected> {
|
|
self.lock_read("get_hns")
|
|
.get_chunks()
|
|
.ok()
|
|
.map(|c| *c.get_hns())
|
|
}
|
|
|
|
fn transmit_haves(&self, index: ValidPieceIndex) {
|
|
let _ = self.have_broadcast_tx.send(index);
|
|
}
|
|
|
|
pub(crate) fn add_peer_if_not_seen(&self, addr: SocketAddr) -> anyhow::Result<bool> {
|
|
match self.peers.add_if_not_seen(addr) {
|
|
Some(handle) => handle,
|
|
None => return Ok(false),
|
|
};
|
|
|
|
self.peer_queue_tx.send(addr)?;
|
|
Ok(true)
|
|
}
|
|
|
|
pub fn stats_snapshot(&self) -> StatsSnapshot {
|
|
use Ordering::*;
|
|
let downloaded_bytes = self.stats.downloaded_and_checked_bytes.load(Relaxed);
|
|
StatsSnapshot {
|
|
downloaded_and_checked_bytes: downloaded_bytes,
|
|
downloaded_and_checked_pieces: self.stats.downloaded_and_checked_pieces.load(Relaxed),
|
|
fetched_bytes: self.stats.fetched_bytes.load(Relaxed),
|
|
uploaded_bytes: self.stats.uploaded_bytes.load(Relaxed),
|
|
total_piece_download_ms: self.stats.total_piece_download_ms.load(Relaxed),
|
|
peer_stats: self.peers.stats(),
|
|
}
|
|
}
|
|
|
|
pub fn per_peer_stats_snapshot(&self, filter: PeerStatsFilter) -> PeerStatsSnapshot {
|
|
PeerStatsSnapshot {
|
|
peers: self
|
|
.peers
|
|
.states
|
|
.iter()
|
|
.filter(|e| filter.state.matches(e.value().state.get()))
|
|
.map(|e| (e.key().to_string(), e.value().into()))
|
|
.collect(),
|
|
}
|
|
}
|
|
|
|
pub async fn wait_until_completed(&self) {
|
|
if self.is_finished() {
|
|
return;
|
|
}
|
|
self.finished_notify.notified().await;
|
|
}
|
|
|
|
pub fn pause(&self) -> anyhow::Result<TorrentStatePaused> {
|
|
self.cancellation_token.cancel();
|
|
|
|
let mut g = self.locked.write();
|
|
|
|
// It should be impossible to make a fatal error after pausing.
|
|
g.fatal_errors_tx.take();
|
|
|
|
let mut chunk_tracker = g
|
|
.chunks
|
|
.take()
|
|
.context("bug: pausing already paused torrent")?;
|
|
for piece_id in g.inflight_pieces.keys().copied() {
|
|
chunk_tracker.mark_piece_broken_if_not_have(piece_id);
|
|
}
|
|
|
|
// g.chunks;
|
|
Ok(TorrentStatePaused {
|
|
shared: self.torrent.clone(),
|
|
files: self.files.take()?,
|
|
chunk_tracker,
|
|
streams: self.streams.clone(),
|
|
})
|
|
}
|
|
|
|
fn on_fatal_error(&self, e: anyhow::Error) -> anyhow::Result<()> {
|
|
let mut g = self.lock_write("fatal_error");
|
|
let tx = g
|
|
.fatal_errors_tx
|
|
.take()
|
|
.context("fatal_errors_tx already taken")?;
|
|
let res = anyhow::anyhow!("fatal error: {:?}", e);
|
|
if tx.send(e).is_err() {
|
|
warn!("there's nowhere to send fatal error, receiver is dead");
|
|
}
|
|
Err(res)
|
|
}
|
|
|
|
pub(crate) fn update_only_files(&self, only_files: &HashSet<usize>) -> anyhow::Result<()> {
|
|
let mut g = self.lock_write("update_only_files");
|
|
let ct = g.get_chunks_mut()?;
|
|
let hns =
|
|
ct.update_only_files(self.torrent().file_infos.iter().map(|f| f.len), only_files)?;
|
|
if !hns.finished() {
|
|
self.reconnect_all_not_needed_peers();
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
// If we have all selected pieces but not necessarily all pieces.
|
|
pub(crate) fn is_finished(&self) -> bool {
|
|
self.get_hns().map(|h| h.finished()).unwrap_or_default()
|
|
}
|
|
|
|
fn has_active_streams_unfinished_files(&self, state: &TorrentStateLocked) -> bool {
|
|
let chunks = match state.get_chunks() {
|
|
Ok(c) => c,
|
|
Err(_) => return false,
|
|
};
|
|
self.streams
|
|
.streamed_file_ids()
|
|
.any(|file_id| !chunks.is_file_finished(&self.torrent.file_infos[file_id]))
|
|
}
|
|
|
|
// We might have the torrent "finished" i.e. no selected files. But if someone is streaming files despite
|
|
// them being selected, we aren't fully "finished".
|
|
fn is_finished_and_no_active_streams(&self) -> bool {
|
|
self.is_finished()
|
|
&& !self.has_active_streams_unfinished_files(
|
|
&self.lock_read("is_finished_and_dont_need_peers"),
|
|
)
|
|
}
|
|
|
|
fn on_piece_completed(&self, id: ValidPieceIndex) -> anyhow::Result<()> {
|
|
let mut g = self.lock_write("on_piece_completed");
|
|
let locked = &mut **g;
|
|
let chunks = locked.get_chunks_mut()?;
|
|
|
|
// if we have all the pieces of the file, reopen it read only
|
|
for (idx, file_info) in self
|
|
.torrent()
|
|
.file_infos
|
|
.iter()
|
|
.enumerate()
|
|
.skip_while(|(_, fi)| !fi.piece_range.contains(&id.get()))
|
|
.take_while(|(_, fi)| fi.piece_range.contains(&id.get()))
|
|
{
|
|
let _remaining = chunks.update_file_have_on_piece_completed(id, idx, file_info);
|
|
}
|
|
|
|
self.streams
|
|
.wake_streams_on_piece_completed(id, &self.torrent.lengths);
|
|
|
|
locked.unflushed_bitv_bytes += self.torrent.lengths.piece_length(id) as u64;
|
|
if locked.unflushed_bitv_bytes >= FLUSH_BITV_EVERY_BYTES {
|
|
locked.try_flush_bitv()
|
|
}
|
|
|
|
let chunks = locked.get_chunks()?;
|
|
if chunks.is_finished() {
|
|
if chunks.get_selected_pieces()[id.get_usize()] {
|
|
locked.try_flush_bitv();
|
|
info!("torrent finished downloading");
|
|
}
|
|
self.finished_notify.notify_waiters();
|
|
|
|
if !self.has_active_streams_unfinished_files(locked) {
|
|
// prevent deadlocks.
|
|
drop(g);
|
|
// There is not poing being connected to peers that have all the torrent, when
|
|
// we don't need anything from them, and they don't need anything from us.
|
|
self.disconnect_all_peers_that_have_full_torrent();
|
|
}
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
fn disconnect_all_peers_that_have_full_torrent(&self) {
|
|
for mut pe in self.peers.states.iter_mut() {
|
|
if let PeerState::Live(l) = pe.value().state.get() {
|
|
if l.has_full_torrent(self.lengths.total_pieces() as usize) {
|
|
let prev = pe.value_mut().state.set_not_needed(&self.peer_stats());
|
|
let _ = prev
|
|
.take_live_no_counters()
|
|
.unwrap()
|
|
.tx
|
|
.send(WriterRequest::Disconnect(Ok(())));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(crate) fn reconnect_all_not_needed_peers(&self) {
|
|
for mut pe in self.peers.states.iter_mut() {
|
|
if pe.state.not_needed_to_queued(&self.peer_stats())
|
|
&& self.peer_queue_tx.send(*pe.key()).is_err()
|
|
{
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
struct PeerHandlerLocked {
|
|
pub i_am_choked: bool,
|
|
}
|
|
|
|
// All peer state that would never be used by other actors should pe put here.
|
|
// This state tracks a live peer.
|
|
struct PeerHandler {
|
|
state: Arc<TorrentStateLive>,
|
|
counters: Arc<AtomicPeerCounters>,
|
|
// Semantically, we don't need an RwLock here, as this is only requested from
|
|
// one future (requester + manage_peer).
|
|
//
|
|
// However as PeerConnectionHandler takes &self everywhere, we need shared mutability.
|
|
// RefCell would do, but tokio is unhappy when we use it.
|
|
locked: RwLock<PeerHandlerLocked>,
|
|
|
|
// This is used to unpause chunk requester once the bitfield
|
|
// is received.
|
|
on_bitfield_notify: Notify,
|
|
|
|
// This is used to unpause after we were choked.
|
|
unchoke_notify: Notify,
|
|
|
|
// This is used to limit the number of chunk requests we send to a peer at a time.
|
|
requests_sem: Semaphore,
|
|
|
|
addr: SocketAddr,
|
|
|
|
tx: PeerTx,
|
|
|
|
first_message_received: AtomicBool,
|
|
}
|
|
|
|
impl<'a> PeerConnectionHandler for &'a PeerHandler {
|
|
fn on_connected(&self, connection_time: Duration) {
|
|
self.counters
|
|
.outgoing_connections
|
|
.fetch_add(1, Ordering::Relaxed);
|
|
#[allow(clippy::cast_possible_truncation)]
|
|
self.counters
|
|
.total_time_connecting_ms
|
|
.fetch_add(connection_time.as_millis() as u64, Ordering::Relaxed);
|
|
}
|
|
|
|
async fn on_received_message(&self, message: Message<ByteBuf<'_>>) -> anyhow::Result<()> {
|
|
// The first message must be "bitfield", but if it's not sent,
|
|
// assume the bitfield is all zeroes and was sent.
|
|
if !matches!(&message, Message::Bitfield(..))
|
|
&& !self.first_message_received.swap(true, Ordering::Relaxed)
|
|
{
|
|
self.on_bitfield_notify.notify_waiters();
|
|
}
|
|
|
|
match message {
|
|
Message::Request(request) => {
|
|
self.on_download_request(request)
|
|
.context("on_download_request")?;
|
|
}
|
|
Message::Bitfield(b) => self
|
|
.on_bitfield(b.clone_to_owned(None))
|
|
.context("on_bitfield")?,
|
|
Message::Choke => self.on_i_am_choked(),
|
|
Message::Unchoke => self.on_i_am_unchoked(),
|
|
Message::Interested => self.on_peer_interested(),
|
|
Message::Piece(piece) => self
|
|
.on_received_piece(piece)
|
|
.await
|
|
.context("on_received_piece")?,
|
|
Message::KeepAlive => {
|
|
trace!("keepalive received");
|
|
}
|
|
Message::Have(h) => self.on_have(h),
|
|
Message::NotInterested => {
|
|
trace!("received \"not interested\", but we don't process it yet")
|
|
}
|
|
Message::Cancel(_) => {
|
|
trace!("received \"cancel\", but we don't process it yet")
|
|
}
|
|
Message::Extended(ExtendedMessage::UtMetadata(UtMetadata::Request(
|
|
metadata_piece_id,
|
|
))) => {
|
|
self.send_metadata_piece(metadata_piece_id)
|
|
.with_context(|| format!("error sending metadata piece {metadata_piece_id}"))?;
|
|
}
|
|
Message::Extended(ExtendedMessage::UtPex(pex)) => {
|
|
self.on_pex_message(pex);
|
|
}
|
|
message => {
|
|
warn!("received unsupported message {:?}, ignoring", message);
|
|
}
|
|
};
|
|
Ok(())
|
|
}
|
|
|
|
fn serialize_bitfield_message_to_buf(&self, buf: &mut Vec<u8>) -> anyhow::Result<usize> {
|
|
let g = self.state.lock_read("serialize_bitfield_message_to_buf");
|
|
let msg = Message::Bitfield(ByteBuf(g.get_chunks()?.get_have_pieces().as_bytes()));
|
|
let len = msg.serialize(buf, &Default::default)?;
|
|
trace!("sending: {:?}, length={}", &msg, len);
|
|
Ok(len)
|
|
}
|
|
|
|
fn on_handshake<B>(&self, handshake: Handshake<B>) -> anyhow::Result<()> {
|
|
self.state.set_peer_live(self.addr, handshake);
|
|
self.tx
|
|
.send(WriterRequest::Message(MessageOwned::Unchoke))?;
|
|
Ok(())
|
|
}
|
|
|
|
fn on_uploaded_bytes(&self, bytes: u32) {
|
|
self.state
|
|
.stats
|
|
.uploaded_bytes
|
|
.fetch_add(bytes as u64, Ordering::Relaxed);
|
|
self.state
|
|
.session_stats
|
|
.uploaded_bytes
|
|
.fetch_add(bytes as u64, Ordering::Relaxed);
|
|
}
|
|
|
|
fn read_chunk(&self, chunk: &ChunkInfo, buf: &mut [u8]) -> anyhow::Result<()> {
|
|
self.state.file_ops().read_chunk(self.addr, chunk, buf)
|
|
}
|
|
|
|
fn on_extended_handshake(&self, hs: &ExtendedHandshake<ByteBuf>) -> anyhow::Result<()> {
|
|
if let Some(peer_pex_msg_id) = hs.ut_pex() {
|
|
trace!("peer supports pex at {peer_pex_msg_id}");
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
fn should_send_bitfield(&self) -> bool {
|
|
if self.state.torrent().options.disable_upload {
|
|
return false;
|
|
}
|
|
|
|
self.state.get_approx_have_bytes() > 0
|
|
}
|
|
|
|
fn should_transmit_have(&self, id: ValidPieceIndex) -> bool {
|
|
if self.state.torrent.options.disable_upload {
|
|
return false;
|
|
}
|
|
let have = self
|
|
.state
|
|
.peers
|
|
.with_live(self.addr, |l| {
|
|
l.bitfield.get(id.get_usize()).map(|p| *p).unwrap_or(true)
|
|
})
|
|
.unwrap_or(true);
|
|
!have
|
|
}
|
|
|
|
fn update_my_extended_handshake(
|
|
&self,
|
|
handshake: &mut ExtendedHandshake<ByteBuf>,
|
|
) -> anyhow::Result<()> {
|
|
let your_ip = self.addr.ip();
|
|
handshake.yourip = Some(YourIP(your_ip));
|
|
let info_bytes = &self.state.torrent().info_bytes;
|
|
if !info_bytes.is_empty() {
|
|
if let Ok(len) = info_bytes.len().try_into() {
|
|
handshake.metadata_size = Some(len);
|
|
}
|
|
}
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
impl PeerHandler {
|
|
fn on_peer_died(self, error: Option<anyhow::Error>) -> anyhow::Result<()> {
|
|
let peers = &self.state.peers;
|
|
let pstats = self.state.peer_stats();
|
|
let handle = self.addr;
|
|
let mut pe = match peers.states.get_mut(&handle) {
|
|
Some(peer) => TimedExistence::new(peer, "on_peer_died"),
|
|
None => {
|
|
warn!("bug: peer not found in table. Forgetting it forever");
|
|
return Ok(());
|
|
}
|
|
};
|
|
let prev = pe.value_mut().state.take(&pstats);
|
|
|
|
match prev {
|
|
PeerState::Connecting(_) => {}
|
|
PeerState::Live(live) => {
|
|
let mut g = self.state.lock_write("mark_chunk_requests_canceled");
|
|
for req in live.inflight_requests {
|
|
trace!(
|
|
"peer dead, marking chunk request cancelled, index={}, chunk={}",
|
|
req.piece_index.get(),
|
|
req.chunk_index
|
|
);
|
|
g.get_chunks_mut()?
|
|
.mark_piece_broken_if_not_have(req.piece_index);
|
|
self.state.new_pieces_notify.notify_waiters();
|
|
}
|
|
}
|
|
PeerState::NotNeeded => {
|
|
// Restore it as std::mem::take() replaced it above.
|
|
pe.value_mut().state.set(PeerState::NotNeeded, &pstats);
|
|
return Ok(());
|
|
}
|
|
s @ PeerState::Queued | s @ PeerState::Dead => {
|
|
warn!("bug: peer was in a wrong state {s:?}, ignoring it forever");
|
|
// Prevent deadlocks.
|
|
drop(pe);
|
|
self.state.peers.drop_peer(handle);
|
|
return Ok(());
|
|
}
|
|
};
|
|
|
|
let _error = match error {
|
|
Some(e) => e,
|
|
None => {
|
|
trace!("peer died without errors, not re-queueing");
|
|
pe.value_mut().state.set(PeerState::NotNeeded, &pstats);
|
|
return Ok(());
|
|
}
|
|
};
|
|
|
|
self.counters.errors.fetch_add(1, Ordering::Relaxed);
|
|
|
|
if self.state.is_finished_and_no_active_streams() {
|
|
debug!("torrent finished, not re-queueing");
|
|
pe.value_mut().state.set(PeerState::NotNeeded, &pstats);
|
|
return Ok(());
|
|
}
|
|
|
|
pe.value_mut().state.set(PeerState::Dead, &pstats);
|
|
|
|
let backoff = pe.value_mut().stats.backoff.next_backoff();
|
|
|
|
// Prevent deadlocks.
|
|
drop(pe);
|
|
|
|
if let Some(dur) = backoff {
|
|
self.state.clone().spawn(
|
|
error_span!(
|
|
parent: self.state.torrent.span.clone(),
|
|
"wait_for_peer",
|
|
peer = handle.to_string(),
|
|
duration = format!("{dur:?}")
|
|
),
|
|
async move {
|
|
trace!("waiting to reconnect again");
|
|
tokio::time::sleep(dur).await;
|
|
trace!("finished waiting");
|
|
self.state
|
|
.peers
|
|
.with_peer_mut(handle, "dead_to_queued", |peer| {
|
|
match peer.state.get() {
|
|
PeerState::Dead => {
|
|
peer.state.set(PeerState::Queued, &self.state.peer_stats())
|
|
}
|
|
other => bail!(
|
|
"peer is in unexpected state: {}. Expected dead",
|
|
other.name()
|
|
),
|
|
};
|
|
Ok(())
|
|
})
|
|
.context("bug: peer disappeared")??;
|
|
self.state.peer_queue_tx.send(handle)?;
|
|
Ok::<_, anyhow::Error>(())
|
|
},
|
|
);
|
|
} else {
|
|
debug!("dropping peer, backoff exhausted");
|
|
self.state.peers.drop_peer(handle);
|
|
};
|
|
Ok(())
|
|
}
|
|
|
|
fn reserve_next_needed_piece(&self) -> anyhow::Result<Option<ValidPieceIndex>> {
|
|
// TODO: locking one inside the other in different order results in deadlocks.
|
|
self.state
|
|
.peers
|
|
.with_live_mut(self.addr, "reserve_next_needed_piece", |live| {
|
|
if self.locked.read().i_am_choked {
|
|
debug!("we are choked, can't reserve next piece");
|
|
return Ok(None);
|
|
}
|
|
let mut g = self.state.lock_write("reserve_next_needed_piece");
|
|
|
|
let n = {
|
|
let mut n_opt = None;
|
|
let bf = &live.bitfield;
|
|
let chunk_tracker = g.get_chunks()?;
|
|
let priority_streamed_pieces = self
|
|
.state
|
|
.streams
|
|
.iter_next_pieces(&self.state.lengths)
|
|
.filter(|pid| {
|
|
!chunk_tracker.is_piece_have(*pid)
|
|
&& !g.inflight_pieces.contains_key(pid)
|
|
});
|
|
let natural_order_pieces = chunk_tracker
|
|
.iter_queued_pieces(&g.file_priorities, &self.state.torrent().file_infos);
|
|
for n in priority_streamed_pieces.chain(natural_order_pieces) {
|
|
if bf.get(n.get() as usize).map(|v| *v) == Some(true) {
|
|
n_opt = Some(n);
|
|
break;
|
|
}
|
|
}
|
|
|
|
match n_opt {
|
|
Some(n_opt) => n_opt,
|
|
None => return Ok(None),
|
|
}
|
|
};
|
|
g.inflight_pieces.insert(
|
|
n,
|
|
InflightPiece {
|
|
peer: self.addr,
|
|
started: Instant::now(),
|
|
},
|
|
);
|
|
g.get_chunks_mut()?.reserve_needed_piece(n);
|
|
Ok(Some(n))
|
|
})
|
|
.transpose()
|
|
.map(|r| r.flatten())
|
|
}
|
|
|
|
/// Try to steal a piece from a slower peer. Threshold is
|
|
/// "how many times is my average download speed faster to be able to steal".
|
|
///
|
|
/// If this returns, an existing in-flight piece was marked to be ours.
|
|
fn try_steal_old_slow_piece(&self, threshold: f64) -> Option<ValidPieceIndex> {
|
|
let my_avg_time = match self.counters.average_piece_download_time() {
|
|
Some(t) => t,
|
|
None => return None,
|
|
};
|
|
|
|
let (stolen_idx, from_peer) = {
|
|
let mut g = self.state.lock_write("try_steal_old_slow_piece");
|
|
let (idx, elapsed, piece_req) = g
|
|
.inflight_pieces
|
|
.iter_mut()
|
|
// don't steal from myself
|
|
.filter(|(_, r)| r.peer != self.addr)
|
|
.map(|(p, r)| (p, r.started.elapsed(), r))
|
|
.max_by_key(|(_, e, _)| *e)?;
|
|
|
|
// heuristic for "too slow peer"
|
|
if elapsed.as_secs_f64() > my_avg_time.as_secs_f64() * threshold {
|
|
// If the piece is locked and someone is actively writing to disk, don't steal it.
|
|
if let Some(_g) = self.state.per_piece_locks[idx.get_usize()].try_write() {
|
|
debug!(
|
|
"will steal piece {} from {}: elapsed time {:?}, my avg piece time: {:?}",
|
|
idx, piece_req.peer, elapsed, my_avg_time
|
|
);
|
|
let old = piece_req.peer;
|
|
piece_req.peer = self.addr;
|
|
piece_req.started = Instant::now();
|
|
(*idx, old)
|
|
} else {
|
|
debug!(?idx, ?piece_req, "attempted to steal but peer was writing");
|
|
return None;
|
|
}
|
|
} else {
|
|
return None;
|
|
}
|
|
};
|
|
|
|
// Send cancellations to old peer and bump counters.
|
|
self.state.peers.on_steal(from_peer, self.addr, stolen_idx);
|
|
|
|
Some(stolen_idx)
|
|
}
|
|
|
|
fn on_download_request(&self, request: Request) -> anyhow::Result<()> {
|
|
if self.state.torrent().options.disable_upload {
|
|
anyhow::bail!("upload disabled, but peer requested a piece")
|
|
}
|
|
|
|
let piece_index = match self.state.lengths.validate_piece_index(request.index) {
|
|
Some(p) => p,
|
|
None => {
|
|
anyhow::bail!(
|
|
"received {:?}, but it is not a valid chunk request (piece index is invalid). Ignoring.",
|
|
request
|
|
);
|
|
}
|
|
};
|
|
|
|
let chunk_info = match self.state.lengths.chunk_info_from_received_data(
|
|
piece_index,
|
|
request.begin,
|
|
request.length,
|
|
) {
|
|
Some(d) => d,
|
|
None => {
|
|
anyhow::bail!(
|
|
"received {:?}, but it is not a valid chunk request (chunk data is invalid). Ignoring.",
|
|
request
|
|
);
|
|
}
|
|
};
|
|
|
|
if !self
|
|
.state
|
|
.lock_read("is_chunk_ready_to_upload")
|
|
.get_chunks()?
|
|
.is_chunk_ready_to_upload(&chunk_info)
|
|
{
|
|
anyhow::bail!(
|
|
"got request for a chunk that is not ready to upload. chunk {:?}",
|
|
&chunk_info
|
|
);
|
|
}
|
|
|
|
// TODO: this is not super efficient as it does copying multiple times.
|
|
// Theoretically, this could be done in the sending code, so that it reads straight into
|
|
// the send buffer.
|
|
let request = WriterRequest::ReadChunkRequest(chunk_info);
|
|
trace!("sending {:?}", &request);
|
|
Ok::<_, anyhow::Error>(self.tx.send(request)?)
|
|
}
|
|
|
|
fn on_have(&self, have: u32) {
|
|
self.state
|
|
.peers
|
|
.with_live_mut(self.addr, "on_have", |live| {
|
|
// If bitfield wasn't allocated yet, let's do it. Some clients start empty so they never
|
|
// send bitfields.
|
|
if live.bitfield.is_empty() {
|
|
live.bitfield = make_piece_bitfield(&self.state.lengths);
|
|
}
|
|
match live.bitfield.get_mut(have as usize) {
|
|
Some(mut v) => *v = true,
|
|
None => {
|
|
warn!("received have {} out of range", have);
|
|
return;
|
|
}
|
|
};
|
|
trace!("updated bitfield with have={}", have);
|
|
});
|
|
self.on_bitfield_notify.notify_waiters();
|
|
}
|
|
|
|
fn on_bitfield(&self, bitfield: ByteBufOwned) -> anyhow::Result<()> {
|
|
if bitfield.len() != self.state.lengths.piece_bitfield_bytes() {
|
|
anyhow::bail!(
|
|
"dropping peer as its bitfield has unexpected size. Got {}, expected {}",
|
|
bitfield.len(),
|
|
self.state.lengths.piece_bitfield_bytes(),
|
|
);
|
|
}
|
|
self.state
|
|
.peers
|
|
.update_bitfield_from_vec(self.addr, bitfield.0.to_vec().into_boxed_slice());
|
|
self.on_bitfield_notify.notify_waiters();
|
|
Ok(())
|
|
}
|
|
|
|
async fn wait_for_any_notify(&self, notify: &Notify, check: impl Fn() -> bool) {
|
|
// To remove possibility of races, we first grab a token, then check
|
|
// if we need it, and only if so, await.
|
|
let notified = notify.notified();
|
|
if check() {
|
|
return;
|
|
}
|
|
notified.await;
|
|
}
|
|
|
|
async fn wait_for_bitfield(&self) {
|
|
self.wait_for_any_notify(&self.on_bitfield_notify, || {
|
|
self.state
|
|
.peers
|
|
.with_live(self.addr, |live| !live.bitfield.is_empty())
|
|
.unwrap_or_default()
|
|
})
|
|
.await;
|
|
}
|
|
|
|
async fn wait_for_unchoke(&self) {
|
|
self.wait_for_any_notify(&self.unchoke_notify, || !self.locked.read().i_am_choked)
|
|
.await;
|
|
}
|
|
|
|
// The job of this is to request chunks and also to keep peer alive.
|
|
// The moment this ends, the peer is disconnected.
|
|
async fn task_peer_chunk_requester(&self) -> anyhow::Result<()> {
|
|
let handle = self.addr;
|
|
self.wait_for_bitfield().await;
|
|
|
|
let mut update_interest = {
|
|
let mut current = false;
|
|
move |h: &PeerHandler, new_value: bool| -> anyhow::Result<()> {
|
|
if new_value != current {
|
|
h.tx.send(if new_value {
|
|
WriterRequest::Message(MessageOwned::Interested)
|
|
} else {
|
|
WriterRequest::Message(MessageOwned::NotInterested)
|
|
})?;
|
|
current = new_value;
|
|
}
|
|
Ok(())
|
|
}
|
|
};
|
|
|
|
loop {
|
|
// If we have full torrent, we don't need to request more pieces.
|
|
// However we might still need to seed them to the peer.
|
|
if self.state.is_finished_and_no_active_streams() {
|
|
update_interest(self, false)?;
|
|
if !self.state.peers.is_peer_interested(self.addr) {
|
|
debug!("nothing left to do, neither of us is interested, disconnecting peer");
|
|
self.tx.send(WriterRequest::Disconnect(Ok(())))?;
|
|
// wait until the receiver gets the message so that it doesn't finish with an error.
|
|
tokio::time::sleep(Duration::from_millis(100)).await;
|
|
return Ok(());
|
|
} else {
|
|
// TODO: wait for a notification of interest, e.g. update of selected files or new streams or change
|
|
// in peer interest.
|
|
tokio::time::sleep(Duration::from_secs(5)).await;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
update_interest(self, true)?;
|
|
aframe!(self.wait_for_unchoke()).await;
|
|
|
|
// Try steal a pice from a very slow peer first. Otherwise we might wait too long
|
|
// to download early pieces.
|
|
// Then try get the next one in queue.
|
|
// Afterwards means we are close to completion, try stealing more aggressively.
|
|
let new_piece_notify = self.state.new_pieces_notify.notified();
|
|
let next = match self
|
|
.try_steal_old_slow_piece(10.)
|
|
.map_or_else(|| self.reserve_next_needed_piece(), |v| Ok(Some(v)))?
|
|
.or_else(|| self.try_steal_old_slow_piece(3.))
|
|
{
|
|
Some(next) => next,
|
|
None => {
|
|
debug!("no pieces to request");
|
|
match aframe!(tokio::time::timeout(
|
|
// Half of default rw timeout not to race with it.
|
|
Duration::from_secs(5),
|
|
new_piece_notify
|
|
))
|
|
.await
|
|
{
|
|
Ok(()) => debug!("woken up, new pieces might be available"),
|
|
Err(_) => debug!("woken up by sleep timer"),
|
|
}
|
|
continue;
|
|
}
|
|
};
|
|
|
|
for chunk in self.state.lengths.iter_chunk_infos(next) {
|
|
let request = Request {
|
|
index: next.get(),
|
|
begin: chunk.offset,
|
|
length: chunk.size,
|
|
};
|
|
|
|
match self
|
|
.state
|
|
.peers
|
|
.with_live_mut(handle, "add chunk request", |live| {
|
|
live.inflight_requests.insert(chunk)
|
|
}) {
|
|
Some(true) => {}
|
|
Some(false) => {
|
|
// This request was already in-flight for this peer for this chunk.
|
|
// This might happen in theory, but not very likely.
|
|
//
|
|
// Example:
|
|
// someone stole a piece from us, and then died, the piece became "needed" again, and we reserved it
|
|
// all before the piece request was processed by us.
|
|
warn!("we already requested {:?} previously", chunk);
|
|
continue;
|
|
}
|
|
// peer died
|
|
None => return Ok(()),
|
|
};
|
|
|
|
loop {
|
|
match aframe!(tokio::time::timeout(
|
|
Duration::from_secs(5),
|
|
aframe!(self.requests_sem.acquire())
|
|
))
|
|
.await
|
|
{
|
|
Ok(acq) => break acq?.forget(),
|
|
Err(_) => continue,
|
|
};
|
|
}
|
|
|
|
if self
|
|
.tx
|
|
.send(WriterRequest::Message(MessageOwned::Request(request)))
|
|
.is_err()
|
|
{
|
|
return Ok(());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn on_i_am_choked(&self) {
|
|
self.locked.write().i_am_choked = true;
|
|
}
|
|
|
|
fn on_peer_interested(&self) {
|
|
trace!("peer is interested");
|
|
self.state.peers.mark_peer_interested(self.addr, true);
|
|
}
|
|
|
|
fn on_i_am_unchoked(&self) {
|
|
trace!("we are unchoked");
|
|
self.locked.write().i_am_choked = false;
|
|
self.unchoke_notify.notify_waiters();
|
|
// 128 should be more than enough to maintain 100mbps
|
|
// for a single peer that has 100ms ping
|
|
// https://www.desmos.com/calculator/x3szur87ps
|
|
self.requests_sem.add_permits(128);
|
|
}
|
|
|
|
async fn on_received_piece(&self, piece: Piece<ByteBuf<'_>>) -> anyhow::Result<()> {
|
|
let piece_index = self
|
|
.state
|
|
.lengths
|
|
.validate_piece_index(piece.index)
|
|
.with_context(|| format!("peer sent an invalid piece {}", piece.index))?;
|
|
let chunk_info = match self.state.lengths.chunk_info_from_received_data(
|
|
piece_index,
|
|
piece.begin,
|
|
piece.block.len().try_into().context("bug")?,
|
|
) {
|
|
Some(i) => i,
|
|
None => {
|
|
anyhow::bail!("peer sent us an invalid piece {:?}", &piece,);
|
|
}
|
|
};
|
|
|
|
self.requests_sem.add_permits(1);
|
|
|
|
// Peer chunk/byte counters.
|
|
self.counters
|
|
.fetched_bytes
|
|
.fetch_add(piece.block.len() as u64, Ordering::Relaxed);
|
|
self.counters.fetched_chunks.fetch_add(1, Ordering::Relaxed);
|
|
|
|
self.state
|
|
.peers
|
|
.with_live_mut(self.addr, "inflight_requests.remove", |h| {
|
|
if !h.inflight_requests.remove(&chunk_info) {
|
|
anyhow::bail!(
|
|
"peer sent us a piece we did not ask. Requested pieces: {:?}. Got: {:?}",
|
|
&h.inflight_requests,
|
|
&piece,
|
|
);
|
|
}
|
|
Ok(())
|
|
})
|
|
.context("peer not found")??;
|
|
|
|
// This one is used to calculate download speed.
|
|
self.state
|
|
.stats
|
|
.fetched_bytes
|
|
.fetch_add(piece.block.as_ref().len() as u64, Ordering::Relaxed);
|
|
self.state
|
|
.session_stats
|
|
.fetched_bytes
|
|
.fetch_add(piece.block.len() as u64, Ordering::Relaxed);
|
|
|
|
fn write_to_disk(
|
|
state: &TorrentStateLive,
|
|
addr: PeerHandle,
|
|
counters: &AtomicPeerCounters,
|
|
piece: &Piece<impl AsRef<[u8]> + std::fmt::Debug>,
|
|
chunk_info: &ChunkInfo,
|
|
) -> anyhow::Result<()> {
|
|
let index = piece.index;
|
|
|
|
// If someone stole the piece by now, ignore it.
|
|
// However if they didn't, don't let them steal it while we are writing.
|
|
// So that by the time we are done writing AND if it was the last piece,
|
|
// we can actually checksum etc.
|
|
// Otherwise it might get into some weird state.
|
|
let ppl_guard = {
|
|
let g = state.lock_read("check_steal");
|
|
|
|
let ppl = state
|
|
.per_piece_locks
|
|
.get(piece.index as usize)
|
|
.map(|l| l.read());
|
|
|
|
match g.inflight_pieces.get(&chunk_info.piece_index) {
|
|
Some(InflightPiece { peer, .. }) if *peer == addr => {}
|
|
Some(InflightPiece { peer, .. }) => {
|
|
debug!(
|
|
"in-flight piece {} was stolen by {}, ignoring",
|
|
chunk_info.piece_index, peer
|
|
);
|
|
return Ok(());
|
|
}
|
|
None => {
|
|
debug!(
|
|
"in-flight piece {} not found. it was probably completed by someone else",
|
|
chunk_info.piece_index
|
|
);
|
|
return Ok(());
|
|
}
|
|
};
|
|
|
|
ppl
|
|
};
|
|
|
|
// While we hold per piece lock, noone can steal it.
|
|
// So we can proceed writing knowing that the piece is ours now and will still be by the time
|
|
// the write is finished.
|
|
match state.file_ops().write_chunk(addr, piece, chunk_info) {
|
|
Ok(()) => {}
|
|
Err(e) => {
|
|
error!("FATAL: error writing chunk to disk: {:?}", e);
|
|
return state.on_fatal_error(e);
|
|
}
|
|
};
|
|
|
|
let full_piece_download_time = {
|
|
let mut g = state.lock_write("mark_chunk_downloaded");
|
|
let chunk_marking_result = g.get_chunks_mut()?.mark_chunk_downloaded(piece);
|
|
trace!(?piece, chunk_marking_result=?chunk_marking_result);
|
|
|
|
match chunk_marking_result {
|
|
Some(ChunkMarkingResult::Completed) => {
|
|
trace!("piece={} done, will write and checksum", piece.index);
|
|
// This will prevent others from stealing it.
|
|
{
|
|
let piece = chunk_info.piece_index;
|
|
g.inflight_pieces.remove(&piece)
|
|
}
|
|
.map(|t| t.started.elapsed())
|
|
}
|
|
Some(ChunkMarkingResult::PreviouslyCompleted) => {
|
|
// TODO: we might need to send cancellations here.
|
|
debug!("piece={} was done by someone else, ignoring", piece.index);
|
|
return Ok(());
|
|
}
|
|
Some(ChunkMarkingResult::NotCompleted) => None,
|
|
None => {
|
|
anyhow::bail!(
|
|
"bogus data received: {:?}, cannot map this to a chunk, dropping peer",
|
|
piece
|
|
);
|
|
}
|
|
}
|
|
};
|
|
|
|
// We don't care about per piece lock anymore, as it's removed from inflight pieces.
|
|
// It shouldn't impact perf anyway, but dropping just in case.
|
|
drop(ppl_guard);
|
|
|
|
let full_piece_download_time = match full_piece_download_time {
|
|
Some(t) => t,
|
|
None => return Ok(()),
|
|
};
|
|
|
|
match state
|
|
.file_ops()
|
|
.check_piece(chunk_info.piece_index)
|
|
.with_context(|| format!("error checking piece={index}"))?
|
|
{
|
|
true => {
|
|
{
|
|
let mut g = state.lock_write("mark_piece_downloaded");
|
|
g.get_chunks_mut()?
|
|
.mark_piece_downloaded(chunk_info.piece_index);
|
|
}
|
|
|
|
// Global piece counters.
|
|
let piece_len = state.lengths.piece_length(chunk_info.piece_index) as u64;
|
|
state
|
|
.stats
|
|
.downloaded_and_checked_bytes
|
|
// This counter is used to compute "is_finished", so using
|
|
// stronger ordering.
|
|
.fetch_add(piece_len, Ordering::Release);
|
|
state
|
|
.stats
|
|
.downloaded_and_checked_pieces
|
|
// This counter is used to compute "is_finished", so using
|
|
// stronger ordering.
|
|
.fetch_add(1, Ordering::Release);
|
|
state
|
|
.stats
|
|
.have_bytes
|
|
.fetch_add(piece_len, Ordering::Relaxed);
|
|
#[allow(clippy::cast_possible_truncation)]
|
|
state.stats.total_piece_download_ms.fetch_add(
|
|
full_piece_download_time.as_millis() as u64,
|
|
Ordering::Relaxed,
|
|
);
|
|
|
|
// Per-peer piece counters.
|
|
counters.on_piece_completed(piece_len, full_piece_download_time);
|
|
state.peers.reset_peer_backoff(addr);
|
|
|
|
debug!("piece={} successfully downloaded and verified", index);
|
|
|
|
state.on_piece_completed(chunk_info.piece_index)?;
|
|
|
|
state.transmit_haves(chunk_info.piece_index);
|
|
}
|
|
false => {
|
|
warn!(
|
|
"checksum for piece={} did not validate. disconecting peer.",
|
|
index
|
|
);
|
|
state
|
|
.lock_write("mark_piece_broken")
|
|
.get_chunks_mut()?
|
|
.mark_piece_broken_if_not_have(chunk_info.piece_index);
|
|
state.new_pieces_notify.notify_waiters();
|
|
anyhow::bail!("i am probably a bogus peer. dying.")
|
|
}
|
|
};
|
|
Ok(())
|
|
}
|
|
|
|
if let Some(dtx) = self.state.disk_work_tx() {
|
|
// TODO: shove all this into one thing to .clone() once rather than 5 times.
|
|
let state = self.state.clone();
|
|
let addr = self.addr;
|
|
let counters = self.counters.clone();
|
|
let piece = piece.clone_to_owned(None);
|
|
let tx = self.tx.clone();
|
|
|
|
let span = tracing::error_span!("deferred_write");
|
|
let work = move || {
|
|
span.in_scope(|| {
|
|
if let Err(e) = write_to_disk(&state, addr, &counters, &piece, &chunk_info) {
|
|
let _ = tx.send(WriterRequest::Disconnect(Err(e)));
|
|
}
|
|
})
|
|
};
|
|
dtx.send(Box::new(work)).await?;
|
|
} else {
|
|
self.state
|
|
.torrent
|
|
.spawner
|
|
.spawn_block_in_place(|| {
|
|
write_to_disk(&self.state, self.addr, &self.counters, &piece, &chunk_info)
|
|
})
|
|
.with_context(|| format!("error processing received chunk {chunk_info:?}"))?;
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
|
|
fn send_metadata_piece(&self, piece_id: u32) -> anyhow::Result<()> {
|
|
let data = &self.state.torrent().info_bytes;
|
|
let metadata_size = data.len();
|
|
if metadata_size == 0 {
|
|
anyhow::bail!("peer requested for info metadata but we don't have it")
|
|
}
|
|
let total_pieces: usize = (metadata_size as u64)
|
|
.div_ceil(CHUNK_SIZE as u64)
|
|
.try_into()?;
|
|
|
|
if piece_id as usize > total_pieces {
|
|
bail!("piece out of bounds")
|
|
}
|
|
|
|
let offset = piece_id * CHUNK_SIZE;
|
|
let end = (offset + CHUNK_SIZE).min(data.len().try_into()?);
|
|
let data = data.slice(offset as usize..end as usize);
|
|
|
|
self.tx
|
|
.send(WriterRequest::Message(Message::Extended(
|
|
ExtendedMessage::UtMetadata(UtMetadata::Data {
|
|
piece: piece_id,
|
|
total_size: end - offset,
|
|
data: data.into(),
|
|
}),
|
|
)))
|
|
.context("error sending UtMetadata: channel closed")?;
|
|
Ok(())
|
|
}
|
|
|
|
fn on_pex_message<B>(&self, msg: UtPex<B>)
|
|
where
|
|
B: AsRef<[u8]> + std::fmt::Debug,
|
|
{
|
|
// TODO: this is just first attempt at pex - will need more sophistication on adding peers - BEP 40, check number of live, seen peers ...
|
|
msg.added_peers().for_each(|peer| {
|
|
self.state
|
|
.add_peer_if_not_seen(peer.addr)
|
|
.map_err(|error| {
|
|
warn!(?peer, ?error, "failed to add peer");
|
|
error
|
|
})
|
|
.ok();
|
|
});
|
|
}
|
|
}
|