19 "github.com/RoaringBitmap/roaring"
20 "github.com/anacrolix/chansync"
21 "github.com/anacrolix/chansync/events"
22 "github.com/anacrolix/dht/v2"
23 . "github.com/anacrolix/generics"
24 "github.com/anacrolix/log"
25 "github.com/anacrolix/missinggo/perf"
26 "github.com/anacrolix/missinggo/slices"
27 "github.com/anacrolix/missinggo/v2"
28 "github.com/anacrolix/missinggo/v2/bitmap"
29 "github.com/anacrolix/missinggo/v2/pubsub"
30 "github.com/anacrolix/multiless"
31 "github.com/anacrolix/sync"
32 request_strategy "github.com/anacrolix/torrent/request-strategy"
33 typedRoaring "github.com/anacrolix/torrent/typed-roaring"
34 "github.com/davecgh/go-spew/spew"
35 "github.com/pion/datachannel"
37 "github.com/anacrolix/torrent/bencode"
38 "github.com/anacrolix/torrent/common"
39 "github.com/anacrolix/torrent/metainfo"
40 pp "github.com/anacrolix/torrent/peer_protocol"
41 "github.com/anacrolix/torrent/segments"
42 "github.com/anacrolix/torrent/storage"
43 "github.com/anacrolix/torrent/tracker"
44 "github.com/anacrolix/torrent/webseed"
45 "github.com/anacrolix/torrent/webtorrent"
48 // Maintains state of torrent within a Client. Many methods should not be called before the info is
49 // available, see .Info and .GotInfo.
51 // Torrent-level aggregate statistics. First in struct to ensure 64-bit
52 // alignment. See #262.
57 networkingEnabled chansync.Flag
58 dataDownloadDisallowed chansync.Flag
59 dataUploadDisallowed bool
60 userOnWriteChunkErr func(error)
62 closed chansync.SetOnce
63 infoHash metainfo.Hash
65 // Values are the piece indices that changed.
66 pieceStateChanges pubsub.PubSub[PieceStateChange]
67 // The size of chunks to request from peers over the wire. This is
68 // normally 16KiB by convention these days.
71 // Total length of the torrent in bytes. Stored because it's not O(1) to
72 // get this from the info dict.
75 // The storage to open when the info dict becomes available.
76 storageOpener *storage.Client
77 // Storage for torrent data.
78 storage *storage.Torrent
79 // Read-locked for using storage, and write-locked for Closing.
80 storageLock sync.RWMutex
82 // TODO: Only announce stuff is used?
83 metainfo metainfo.MetaInfo
85 // The info dict. nil if we don't have it (yet).
87 fileIndex segments.Index
90 webSeeds map[string]*Peer
91 // Active peer connections, running message stream loops. TODO: Make this
92 // open (not-closed) connections only.
93 conns map[*PeerConn]struct{}
94 maxEstablishedConns int
95 // Set of addrs to which we're attempting to connect. Connections are
96 // half-open until all handshakes are completed.
97 halfOpen map[string]PeerInfo
99 // Reserve of peers to connect to. A peer can be both here and in the
100 // active connections if were told about the peer after connecting with
101 // them. That encourages us to reconnect to peers that are well known in
103 peers prioritizedPeers
104 // Whether we want to know to know more peers.
105 wantPeersEvent missinggo.Event
106 // An announcer for each tracker URL.
107 trackerAnnouncers map[string]torrentTrackerAnnouncer
108 // How many times we've initiated a DHT announce. TODO: Move into stats.
111 // Name used if the info name isn't available. Should be cleared when the
112 // Info does become available.
116 // The bencoded bytes of the info dict. This is actively manipulated if
117 // the info bytes aren't initially available, and we try to fetch them
120 // Each element corresponds to the 16KiB metadata pieces. If true, we have
121 // received that piece.
122 metadataCompletedChunks []bool
123 metadataChanged sync.Cond
125 // Closed when .Info is obtained.
126 gotMetainfoC chan struct{}
128 readers map[*reader]struct{}
129 _readerNowPieces bitmap.Bitmap
130 _readerReadaheadPieces bitmap.Bitmap
132 // A cache of pieces we need to get. Calculated from various piece and
133 // file priorities and completion states elsewhere.
134 _pendingPieces roaring.Bitmap
135 // A cache of completed piece indices.
136 _completedPieces roaring.Bitmap
137 // Pieces that need to be hashed.
138 piecesQueuedForHash bitmap.Bitmap
139 activePieceHashes int
140 initialPieceCheckDisabled bool
142 connsWithAllPieces map[*Peer]struct{}
143 // Count of each request across active connections.
144 pendingRequests map[RequestIndex]*Peer
145 lastRequested map[RequestIndex]time.Time
146 // Chunks we've written to since the corresponding piece was last checked.
147 dirtyChunks typedRoaring.Bitmap[RequestIndex]
151 // Is On when all pieces are complete.
152 Complete chansync.Flag
154 // Torrent sources in use keyed by the source string.
155 activeSources sync.Map
156 sourcesLogger log.Logger
158 smartBanCache smartBanCache
161 func (t *Torrent) selectivePieceAvailabilityFromPeers(i pieceIndex) (count int) {
162 // This could be done with roaring.BitSliceIndexing.
163 t.iterPeers(func(peer *Peer) {
164 if _, ok := t.connsWithAllPieces[peer]; ok {
167 if peer.peerHasPiece(i) {
174 func (t *Torrent) decPieceAvailability(i pieceIndex) {
179 if p.relativeAvailability <= 0 {
180 panic(p.relativeAvailability)
182 p.relativeAvailability--
183 t.updatePieceRequestOrder(i)
186 func (t *Torrent) incPieceAvailability(i pieceIndex) {
187 // If we don't the info, this should be reconciled when we do.
190 p.relativeAvailability++
191 t.updatePieceRequestOrder(i)
195 func (t *Torrent) readerNowPieces() bitmap.Bitmap {
196 return t._readerNowPieces
199 func (t *Torrent) readerReadaheadPieces() bitmap.Bitmap {
200 return t._readerReadaheadPieces
203 func (t *Torrent) ignorePieceForRequests(i pieceIndex) bool {
204 return !t.wantPieceIndex(i)
207 // Returns a channel that is closed when the Torrent is closed.
208 func (t *Torrent) Closed() events.Done {
209 return t.closed.Done()
212 // KnownSwarm returns the known subset of the peers in the Torrent's swarm, including active,
213 // pending, and half-open peers.
214 func (t *Torrent) KnownSwarm() (ks []PeerInfo) {
215 // Add pending peers to the list
216 t.peers.Each(func(peer PeerInfo) {
217 ks = append(ks, peer)
220 // Add half-open peers to the list
221 for _, peer := range t.halfOpen {
222 ks = append(ks, peer)
225 // Add active peers to the list
226 for conn := range t.conns {
227 ks = append(ks, PeerInfo{
229 Addr: conn.RemoteAddr,
230 Source: conn.Discovery,
231 // > If the connection is encrypted, that's certainly enough to set SupportsEncryption.
232 // > But if we're not connected to them with an encrypted connection, I couldn't say
233 // > what's appropriate. We can carry forward the SupportsEncryption value as we
234 // > received it from trackers/DHT/PEX, or just use the encryption state for the
235 // > connection. It's probably easiest to do the latter for now.
236 // https://github.com/anacrolix/torrent/pull/188
237 SupportsEncryption: conn.headerEncrypted,
244 func (t *Torrent) setChunkSize(size pp.Integer) {
246 t.chunkPool = sync.Pool{
247 New: func() interface{} {
248 b := make([]byte, size)
254 func (t *Torrent) pieceComplete(piece pieceIndex) bool {
255 return t._completedPieces.Contains(bitmap.BitIndex(piece))
258 func (t *Torrent) pieceCompleteUncached(piece pieceIndex) storage.Completion {
259 if t.storage == nil {
260 return storage.Completion{Complete: false, Ok: true}
262 return t.pieces[piece].Storage().Completion()
265 // There's a connection to that address already.
266 func (t *Torrent) addrActive(addr string) bool {
267 if _, ok := t.halfOpen[addr]; ok {
270 for c := range t.conns {
272 if ra.String() == addr {
279 func (t *Torrent) appendUnclosedConns(ret []*PeerConn) []*PeerConn {
280 return t.appendConns(ret, func(conn *PeerConn) bool {
281 return !conn.closed.IsSet()
285 func (t *Torrent) appendConns(ret []*PeerConn, f func(*PeerConn) bool) []*PeerConn {
286 for c := range t.conns {
294 func (t *Torrent) addPeer(p PeerInfo) (added bool) {
296 torrent.Add(fmt.Sprintf("peers added by source %q", p.Source), 1)
297 if t.closed.IsSet() {
300 if ipAddr, ok := tryIpPortFromNetAddr(p.Addr); ok {
301 if cl.badPeerIPPort(ipAddr.IP, ipAddr.Port) {
302 torrent.Add("peers not added because of bad addr", 1)
303 // cl.logger.Printf("peers not added because of bad addr: %v", p)
307 if replaced, ok := t.peers.AddReturningReplacedPeer(p); ok {
308 torrent.Add("peers replaced", 1)
309 if !replaced.equal(p) {
310 t.logger.WithDefaultLevel(log.Debug).Printf("added %v replacing %v", p, replaced)
317 for t.peers.Len() > cl.config.TorrentPeersHighWater {
318 _, ok := t.peers.DeleteMin()
320 torrent.Add("excess reserve peers discarded", 1)
326 func (t *Torrent) invalidateMetadata() {
327 for i := 0; i < len(t.metadataCompletedChunks); i++ {
328 t.metadataCompletedChunks[i] = false
331 t.gotMetainfoC = make(chan struct{})
336 func (t *Torrent) saveMetadataPiece(index int, data []byte) {
340 if index >= len(t.metadataCompletedChunks) {
341 t.logger.Printf("%s: ignoring metadata piece %d", t, index)
344 copy(t.metadataBytes[(1<<14)*index:], data)
345 t.metadataCompletedChunks[index] = true
348 func (t *Torrent) metadataPieceCount() int {
349 return (len(t.metadataBytes) + (1 << 14) - 1) / (1 << 14)
352 func (t *Torrent) haveMetadataPiece(piece int) bool {
354 return (1<<14)*piece < len(t.metadataBytes)
356 return piece < len(t.metadataCompletedChunks) && t.metadataCompletedChunks[piece]
360 func (t *Torrent) metadataSize() int {
361 return len(t.metadataBytes)
364 func infoPieceHashes(info *metainfo.Info) (ret [][]byte) {
365 for i := 0; i < len(info.Pieces); i += sha1.Size {
366 ret = append(ret, info.Pieces[i:i+sha1.Size])
371 func (t *Torrent) makePieces() {
372 hashes := infoPieceHashes(t.info)
373 t.pieces = make([]Piece, len(hashes))
374 for i, hash := range hashes {
375 piece := &t.pieces[i]
377 piece.index = pieceIndex(i)
378 piece.noPendingWrites.L = &piece.pendingWritesMutex
379 piece.hash = (*metainfo.Hash)(unsafe.Pointer(&hash[0]))
381 beginFile := pieceFirstFileIndex(piece.torrentBeginOffset(), files)
382 endFile := pieceEndFileIndex(piece.torrentEndOffset(), files)
383 piece.files = files[beginFile:endFile]
384 piece.undirtiedChunksIter = undirtiedChunksIter{
385 TorrentDirtyChunks: &t.dirtyChunks,
386 StartRequestIndex: piece.requestIndexOffset(),
387 EndRequestIndex: piece.requestIndexOffset() + piece.numChunks(),
392 // Returns the index of the first file containing the piece. files must be
393 // ordered by offset.
394 func pieceFirstFileIndex(pieceOffset int64, files []*File) int {
395 for i, f := range files {
396 if f.offset+f.length > pieceOffset {
403 // Returns the index after the last file containing the piece. files must be
404 // ordered by offset.
405 func pieceEndFileIndex(pieceEndOffset int64, files []*File) int {
406 for i, f := range files {
407 if f.offset+f.length >= pieceEndOffset {
414 func (t *Torrent) cacheLength() {
416 for _, f := range t.info.UpvertedFiles() {
422 // TODO: This shouldn't fail for storage reasons. Instead we should handle storage failure
424 func (t *Torrent) setInfo(info *metainfo.Info) error {
425 if err := validateInfo(info); err != nil {
426 return fmt.Errorf("bad info: %s", err)
428 if t.storageOpener != nil {
430 t.storage, err = t.storageOpener.OpenTorrent(info, t.infoHash)
432 return fmt.Errorf("error opening torrent storage: %s", err)
439 t.fileIndex = segments.NewIndex(common.LengthIterFromUpvertedFiles(info.UpvertedFiles()))
440 t.displayName = "" // Save a few bytes lol.
447 func (t *Torrent) pieceRequestOrderKey(i int) request_strategy.PieceRequestOrderKey {
448 return request_strategy.PieceRequestOrderKey{
449 InfoHash: t.infoHash,
454 // This seems to be all the follow-up tasks after info is set, that can't fail.
455 func (t *Torrent) onSetInfo() {
456 t.initPieceRequestOrder()
457 for i := range t.pieces {
459 // Need to add relativeAvailability before updating piece completion, as that may result in conns
461 if p.relativeAvailability != 0 {
462 panic(p.relativeAvailability)
464 p.relativeAvailability = t.selectivePieceAvailabilityFromPeers(i)
465 t.addRequestOrderPiece(i)
466 t.updatePieceCompletion(pieceIndex(i))
467 if !t.initialPieceCheckDisabled && !p.storageCompletionOk {
468 // t.logger.Printf("piece %s completion unknown, queueing check", p)
469 t.queuePieceCheck(pieceIndex(i))
472 t.cl.event.Broadcast()
473 close(t.gotMetainfoC)
474 t.updateWantPeersEvent()
475 t.pendingRequests = make(map[RequestIndex]*Peer)
476 t.lastRequested = make(map[RequestIndex]time.Time)
477 t.tryCreateMorePieceHashers()
478 t.iterPeers(func(p *Peer) {
480 p.updateRequests("onSetInfo")
484 // Called when metadata for a torrent becomes available.
485 func (t *Torrent) setInfoBytesLocked(b []byte) error {
486 if metainfo.HashBytes(b) != t.infoHash {
487 return errors.New("info bytes have wrong hash")
489 var info metainfo.Info
490 if err := bencode.Unmarshal(b, &info); err != nil {
491 return fmt.Errorf("error unmarshalling info bytes: %s", err)
494 t.metadataCompletedChunks = nil
498 if err := t.setInfo(&info); err != nil {
505 func (t *Torrent) haveAllMetadataPieces() bool {
509 if t.metadataCompletedChunks == nil {
512 for _, have := range t.metadataCompletedChunks {
520 // TODO: Propagate errors to disconnect peer.
521 func (t *Torrent) setMetadataSize(size int) (err error) {
523 // We already know the correct metadata size.
526 if uint32(size) > maxMetadataSize {
527 return errors.New("bad size")
529 if len(t.metadataBytes) == size {
532 t.metadataBytes = make([]byte, size)
533 t.metadataCompletedChunks = make([]bool, (size+(1<<14)-1)/(1<<14))
534 t.metadataChanged.Broadcast()
535 for c := range t.conns {
536 c.requestPendingMetadata()
541 // The current working name for the torrent. Either the name in the info dict,
542 // or a display name given such as by the dn value in a magnet link, or "".
543 func (t *Torrent) name() string {
545 defer t.nameMu.RUnlock()
547 return t.info.BestName()
549 if t.displayName != "" {
552 return "infohash:" + t.infoHash.HexString()
555 func (t *Torrent) pieceState(index pieceIndex) (ret PieceState) {
556 p := &t.pieces[index]
557 ret.Priority = t.piecePriority(index)
558 ret.Completion = p.completion()
559 ret.QueuedForHash = p.queuedForHash()
560 ret.Hashing = p.hashing
561 ret.Checking = ret.QueuedForHash || ret.Hashing
562 ret.Marking = p.marking
563 if !ret.Complete && t.piecePartiallyDownloaded(index) {
569 func (t *Torrent) metadataPieceSize(piece int) int {
570 return metadataPieceSize(len(t.metadataBytes), piece)
573 func (t *Torrent) newMetadataExtensionMessage(c *PeerConn, msgType pp.ExtendedMetadataRequestMsgType, piece int, data []byte) pp.Message {
576 ExtendedID: c.PeerExtensionIDs[pp.ExtensionNameMetadata],
577 ExtendedPayload: append(bencode.MustMarshal(pp.ExtendedMetadataRequestMsg{
579 TotalSize: len(t.metadataBytes),
585 type pieceAvailabilityRun struct {
590 func (me pieceAvailabilityRun) String() string {
591 return fmt.Sprintf("%v(%v)", me.Count, me.Availability)
594 func (t *Torrent) pieceAvailabilityRuns() (ret []pieceAvailabilityRun) {
595 rle := missinggo.NewRunLengthEncoder(func(el interface{}, count uint64) {
596 ret = append(ret, pieceAvailabilityRun{Availability: el.(int), Count: int(count)})
598 for i := range t.pieces {
599 rle.Append(t.pieces[i].availability(), 1)
605 func (t *Torrent) pieceAvailabilityFrequencies() (freqs []int) {
606 freqs = make([]int, t.numActivePeers()+1)
607 for i := range t.pieces {
608 freqs[t.piece(i).availability()]++
613 func (t *Torrent) pieceStateRuns() (ret PieceStateRuns) {
614 rle := missinggo.NewRunLengthEncoder(func(el interface{}, count uint64) {
615 ret = append(ret, PieceStateRun{
616 PieceState: el.(PieceState),
620 for index := range t.pieces {
621 rle.Append(t.pieceState(pieceIndex(index)), 1)
627 // Produces a small string representing a PieceStateRun.
628 func (psr PieceStateRun) String() (ret string) {
629 ret = fmt.Sprintf("%d", psr.Length)
630 ret += func() string {
631 switch psr.Priority {
632 case PiecePriorityNext:
634 case PiecePriorityNormal:
636 case PiecePriorityReadahead:
638 case PiecePriorityNow:
640 case PiecePriorityHigh:
649 if psr.QueuedForHash {
667 func (t *Torrent) writeStatus(w io.Writer) {
668 fmt.Fprintf(w, "Infohash: %s\n", t.infoHash.HexString())
669 fmt.Fprintf(w, "Metadata length: %d\n", t.metadataSize())
671 fmt.Fprintf(w, "Metadata have: ")
672 for _, h := range t.metadataCompletedChunks {
673 fmt.Fprintf(w, "%c", func() rune {
683 fmt.Fprintf(w, "Piece length: %s\n",
686 return fmt.Sprintf("%v (%v chunks)",
688 float64(t.usualPieceSize())/float64(t.chunkSize))
695 fmt.Fprintf(w, "Num Pieces: %d (%d completed)\n", t.numPieces(), t.numPiecesCompleted())
696 fmt.Fprintf(w, "Piece States: %s\n", t.pieceStateRuns())
697 // Generates a huge, unhelpful listing when piece availability is very scattered. Prefer
698 // availability frequencies instead.
700 fmt.Fprintf(w, "Piece availability: %v\n", strings.Join(func() (ret []string) {
701 for _, run := range t.pieceAvailabilityRuns() {
702 ret = append(ret, run.String())
707 fmt.Fprintf(w, "Piece availability frequency: %v\n", strings.Join(
708 func() (ret []string) {
709 for avail, freq := range t.pieceAvailabilityFrequencies() {
713 ret = append(ret, fmt.Sprintf("%v: %v", avail, freq))
719 fmt.Fprintf(w, "Reader Pieces:")
720 t.forReaderOffsetPieces(func(begin, end pieceIndex) (again bool) {
721 fmt.Fprintf(w, " %d:%d", begin, end)
726 fmt.Fprintf(w, "Enabled trackers:\n")
728 tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', 0)
729 fmt.Fprintf(tw, " URL\tExtra\n")
730 for _, ta := range slices.Sort(slices.FromMapElems(t.trackerAnnouncers), func(l, r torrentTrackerAnnouncer) bool {
733 var luns, runs url.URL = *lu, *ru
736 var ml missinggo.MultiLess
737 ml.StrictNext(luns.String() == runs.String(), luns.String() < runs.String())
738 ml.StrictNext(lu.String() == ru.String(), lu.String() < ru.String())
740 }).([]torrentTrackerAnnouncer) {
741 fmt.Fprintf(tw, " %q\t%v\n", ta.URL(), ta.statusLine())
746 fmt.Fprintf(w, "DHT Announces: %d\n", t.numDHTAnnounces)
748 spew.NewDefaultConfig()
749 spew.Fdump(w, t.statsLocked())
751 peers := t.peersAsSlice()
752 sort.Slice(peers, func(_i, _j int) bool {
755 if less, ok := multiless.New().EagerSameLess(
756 i.downloadRate() == j.downloadRate(), i.downloadRate() < j.downloadRate(),
760 return worseConn(i, j)
762 for i, c := range peers {
763 fmt.Fprintf(w, "%2d. ", i+1)
768 func (t *Torrent) haveInfo() bool {
772 // Returns a run-time generated MetaInfo that includes the info bytes and
773 // announce-list as currently known to the client.
774 func (t *Torrent) newMetaInfo() metainfo.MetaInfo {
775 return metainfo.MetaInfo{
776 CreationDate: time.Now().Unix(),
777 Comment: "dynamic metainfo from client",
778 CreatedBy: "go.torrent",
779 AnnounceList: t.metainfo.UpvertedAnnounceList().Clone(),
780 InfoBytes: func() []byte {
782 return t.metadataBytes
787 UrlList: func() []string {
788 ret := make([]string, 0, len(t.webSeeds))
789 for url := range t.webSeeds {
790 ret = append(ret, url)
798 func (t *Torrent) BytesMissing() (n int64) {
800 n = t.bytesMissingLocked()
805 func (t *Torrent) bytesMissingLocked() int64 {
809 func iterFlipped(b *roaring.Bitmap, end uint64, cb func(uint32) bool) {
810 roaring.Flip(b, 0, end).Iterate(cb)
813 func (t *Torrent) bytesLeft() (left int64) {
814 iterFlipped(&t._completedPieces, uint64(t.numPieces()), func(x uint32) bool {
815 p := t.piece(pieceIndex(x))
816 left += int64(p.length() - p.numDirtyBytes())
822 // Bytes left to give in tracker announces.
823 func (t *Torrent) bytesLeftAnnounce() int64 {
831 func (t *Torrent) piecePartiallyDownloaded(piece pieceIndex) bool {
832 if t.pieceComplete(piece) {
835 if t.pieceAllDirty(piece) {
838 return t.pieces[piece].hasDirtyChunks()
841 func (t *Torrent) usualPieceSize() int {
842 return int(t.info.PieceLength)
845 func (t *Torrent) numPieces() pieceIndex {
846 return pieceIndex(t.info.NumPieces())
849 func (t *Torrent) numPiecesCompleted() (num pieceIndex) {
850 return pieceIndex(t._completedPieces.GetCardinality())
853 func (t *Torrent) close(wg *sync.WaitGroup) (err error) {
855 err = errors.New("already closed")
858 if t.storage != nil {
863 defer t.storageLock.Unlock()
864 if f := t.storage.Close; f != nil {
867 t.logger.WithDefaultLevel(log.Warning).Printf("error closing storage: %v", err1)
872 t.iterPeers(func(p *Peer) {
875 if t.storage != nil {
876 t.deletePieceRequestOrder()
878 for i := range t.pieces {
880 if p.relativeAvailability != 0 {
881 panic(fmt.Sprintf("piece %v has relative availability %v", i, p.relativeAvailability))
885 t.cl.event.Broadcast()
886 t.pieceStateChanges.Close()
887 t.updateWantPeersEvent()
891 func (t *Torrent) requestOffset(r Request) int64 {
892 return torrentRequestOffset(*t.length, int64(t.usualPieceSize()), r)
895 // Return the request that would include the given offset into the torrent data. Returns !ok if
896 // there is no such request.
897 func (t *Torrent) offsetRequest(off int64) (req Request, ok bool) {
898 return torrentOffsetRequest(*t.length, t.info.PieceLength, int64(t.chunkSize), off)
901 func (t *Torrent) writeChunk(piece int, begin int64, data []byte) (err error) {
902 defer perf.ScopeTimerErr(&err)()
903 n, err := t.pieces[piece].Storage().WriteAt(data, begin)
904 if err == nil && n != len(data) {
905 err = io.ErrShortWrite
910 func (t *Torrent) bitfield() (bf []bool) {
911 bf = make([]bool, t.numPieces())
912 t._completedPieces.Iterate(func(piece uint32) (again bool) {
919 func (t *Torrent) pieceNumChunks(piece pieceIndex) chunkIndexType {
920 return chunkIndexType((t.pieceLength(piece) + t.chunkSize - 1) / t.chunkSize)
923 func (t *Torrent) chunksPerRegularPiece() chunkIndexType {
924 return chunkIndexType((pp.Integer(t.usualPieceSize()) + t.chunkSize - 1) / t.chunkSize)
927 func (t *Torrent) numRequests() RequestIndex {
928 if t.numPieces() == 0 {
931 return RequestIndex(t.numPieces()-1)*t.chunksPerRegularPiece() + t.pieceNumChunks(t.numPieces()-1)
934 func (t *Torrent) pendAllChunkSpecs(pieceIndex pieceIndex) {
935 t.dirtyChunks.RemoveRange(
936 uint64(t.pieceRequestIndexOffset(pieceIndex)),
937 uint64(t.pieceRequestIndexOffset(pieceIndex+1)))
940 func (t *Torrent) pieceLength(piece pieceIndex) pp.Integer {
941 if t.info.PieceLength == 0 {
942 // There will be no variance amongst pieces. Only pain.
945 if piece == t.numPieces()-1 {
946 ret := pp.Integer(*t.length % t.info.PieceLength)
951 return pp.Integer(t.info.PieceLength)
954 func (t *Torrent) smartBanBlockCheckingWriter(piece pieceIndex) *blockCheckingWriter {
955 return &blockCheckingWriter{
956 cache: &t.smartBanCache,
957 requestIndex: t.pieceRequestIndexOffset(piece),
958 chunkSize: t.chunkSize.Int(),
962 func (t *Torrent) hashPiece(piece pieceIndex) (
964 // These are peers that sent us blocks that differ from what we hash here.
965 differingPeers map[bannableAddr]struct{},
969 p.waitNoPendingWrites()
970 storagePiece := t.pieces[piece].Storage()
972 // Does the backend want to do its own hashing?
973 if i, ok := storagePiece.PieceImpl.(storage.SelfHashing); ok {
974 var sum metainfo.Hash
975 // log.Printf("A piece decided to self-hash: %d", piece)
976 sum, err = i.SelfHash()
977 missinggo.CopyExact(&ret, sum)
981 hash := pieceHash.New()
982 const logPieceContents = false
983 smartBanWriter := t.smartBanBlockCheckingWriter(piece)
984 writers := []io.Writer{hash, smartBanWriter}
985 var examineBuf bytes.Buffer
986 if logPieceContents {
987 writers = append(writers, &examineBuf)
989 _, err = storagePiece.WriteTo(io.MultiWriter(writers...))
990 if logPieceContents {
991 t.logger.WithDefaultLevel(log.Debug).Printf("hashed %q with copy err %v", examineBuf.Bytes(), err)
993 smartBanWriter.Flush()
994 differingPeers = smartBanWriter.badPeers
995 missinggo.CopyExact(&ret, hash.Sum(nil))
999 func (t *Torrent) haveAnyPieces() bool {
1000 return !t._completedPieces.IsEmpty()
1003 func (t *Torrent) haveAllPieces() bool {
1007 return t._completedPieces.GetCardinality() == bitmap.BitRange(t.numPieces())
1010 func (t *Torrent) havePiece(index pieceIndex) bool {
1011 return t.haveInfo() && t.pieceComplete(index)
1014 func (t *Torrent) maybeDropMutuallyCompletePeer(
1015 // I'm not sure about taking peer here, not all peer implementations actually drop. Maybe that's
1019 if !t.cl.config.DropMutuallyCompletePeers {
1022 if !t.haveAllPieces() {
1025 if all, known := p.peerHasAllPieces(); !(known && all) {
1031 t.logger.WithDefaultLevel(log.Debug).Printf("dropping %v, which is mutually complete", p)
1035 func (t *Torrent) haveChunk(r Request) (ret bool) {
1037 // log.Println("have chunk", r, ret)
1042 if t.pieceComplete(pieceIndex(r.Index)) {
1045 p := &t.pieces[r.Index]
1046 return !p.pendingChunk(r.ChunkSpec, t.chunkSize)
1049 func chunkIndexFromChunkSpec(cs ChunkSpec, chunkSize pp.Integer) chunkIndexType {
1050 return chunkIndexType(cs.Begin / chunkSize)
1053 func (t *Torrent) wantPieceIndex(index pieceIndex) bool {
1054 return t._pendingPieces.Contains(uint32(index))
1057 // A pool of []*PeerConn, to reduce allocations in functions that need to index or sort Torrent
1058 // conns (which is a map).
1059 var peerConnSlices sync.Pool
1061 func getPeerConnSlice(cap int) []*PeerConn {
1062 getInterface := peerConnSlices.Get()
1063 if getInterface == nil {
1064 return make([]*PeerConn, 0, cap)
1066 return getInterface.([]*PeerConn)[:0]
1070 // The worst connection is one that hasn't been sent, or sent anything useful for the longest. A bad
1071 // connection is one that usually sends us unwanted pieces, or has been in the worse half of the
1072 // established connections for more than a minute. This is O(n log n). If there was a way to not
1073 // consider the position of a conn relative to the total number, it could be reduced to O(n).
1074 func (t *Torrent) worstBadConn() (ret *PeerConn) {
1075 wcs := worseConnSlice{conns: t.appendUnclosedConns(getPeerConnSlice(len(t.conns)))}
1076 defer peerConnSlices.Put(wcs.conns)
1079 for wcs.Len() != 0 {
1080 c := heap.Pop(&wcs).(*PeerConn)
1081 if c._stats.ChunksReadWasted.Int64() >= 6 && c._stats.ChunksReadWasted.Int64() > c._stats.ChunksReadUseful.Int64() {
1084 // If the connection is in the worst half of the established
1085 // connection quota and is older than a minute.
1086 if wcs.Len() >= (t.maxEstablishedConns+1)/2 {
1087 // Give connections 1 minute to prove themselves.
1088 if time.Since(c.completedHandshake) > time.Minute {
1096 type PieceStateChange struct {
1101 func (t *Torrent) publishPieceChange(piece pieceIndex) {
1102 t.cl._mu.Defer(func() {
1103 cur := t.pieceState(piece)
1104 p := &t.pieces[piece]
1105 if cur != p.publicPieceState {
1106 p.publicPieceState = cur
1107 t.pieceStateChanges.Publish(PieceStateChange{
1115 func (t *Torrent) pieceNumPendingChunks(piece pieceIndex) pp.Integer {
1116 if t.pieceComplete(piece) {
1119 return pp.Integer(t.pieceNumChunks(piece) - t.pieces[piece].numDirtyChunks())
1122 func (t *Torrent) pieceAllDirty(piece pieceIndex) bool {
1123 return t.pieces[piece].allChunksDirty()
1126 func (t *Torrent) readersChanged() {
1127 t.updateReaderPieces()
1128 t.updateAllPiecePriorities("Torrent.readersChanged")
1131 func (t *Torrent) updateReaderPieces() {
1132 t._readerNowPieces, t._readerReadaheadPieces = t.readerPiecePriorities()
1135 func (t *Torrent) readerPosChanged(from, to pieceRange) {
1139 t.updateReaderPieces()
1140 // Order the ranges, high and low.
1142 if l.begin > h.begin {
1145 if l.end < h.begin {
1146 // Two distinct ranges.
1147 t.updatePiecePriorities(l.begin, l.end, "Torrent.readerPosChanged")
1148 t.updatePiecePriorities(h.begin, h.end, "Torrent.readerPosChanged")
1155 t.updatePiecePriorities(l.begin, end, "Torrent.readerPosChanged")
1159 func (t *Torrent) maybeNewConns() {
1160 // Tickle the accept routine.
1161 t.cl.event.Broadcast()
1165 func (t *Torrent) piecePriorityChanged(piece pieceIndex, reason string) {
1166 if t._pendingPieces.Contains(uint32(piece)) {
1167 t.iterPeers(func(c *Peer) {
1168 // if c.requestState.Interested {
1171 if !c.isLowOnRequests() {
1174 if !c.peerHasPiece(piece) {
1177 if c.requestState.Interested && c.peerChoking && !c.peerAllowedFast.Contains(piece) {
1180 c.updateRequests(reason)
1184 t.publishPieceChange(piece)
1187 func (t *Torrent) updatePiecePriority(piece pieceIndex, reason string) {
1188 if !t.closed.IsSet() {
1189 // It would be possible to filter on pure-priority changes here to avoid churning the piece
1191 t.updatePieceRequestOrder(piece)
1193 p := &t.pieces[piece]
1194 newPrio := p.uncachedPriority()
1195 // t.logger.Printf("torrent %p: piece %d: uncached priority: %v", t, piece, newPrio)
1196 if newPrio == PiecePriorityNone {
1197 if !t._pendingPieces.CheckedRemove(uint32(piece)) {
1201 if !t._pendingPieces.CheckedAdd(uint32(piece)) {
1205 t.piecePriorityChanged(piece, reason)
1208 func (t *Torrent) updateAllPiecePriorities(reason string) {
1209 t.updatePiecePriorities(0, t.numPieces(), reason)
1212 // Update all piece priorities in one hit. This function should have the same
1213 // output as updatePiecePriority, but across all pieces.
1214 func (t *Torrent) updatePiecePriorities(begin, end pieceIndex, reason string) {
1215 for i := begin; i < end; i++ {
1216 t.updatePiecePriority(i, reason)
1220 // Returns the range of pieces [begin, end) that contains the extent of bytes.
1221 func (t *Torrent) byteRegionPieces(off, size int64) (begin, end pieceIndex) {
1222 if off >= *t.length {
1232 begin = pieceIndex(off / t.info.PieceLength)
1233 end = pieceIndex((off + size + t.info.PieceLength - 1) / t.info.PieceLength)
1234 if end > pieceIndex(t.info.NumPieces()) {
1235 end = pieceIndex(t.info.NumPieces())
1240 // Returns true if all iterations complete without breaking. Returns the read regions for all
1241 // readers. The reader regions should not be merged as some callers depend on this method to
1242 // enumerate readers.
1243 func (t *Torrent) forReaderOffsetPieces(f func(begin, end pieceIndex) (more bool)) (all bool) {
1244 for r := range t.readers {
1246 if p.begin >= p.end {
1249 if !f(p.begin, p.end) {
1256 func (t *Torrent) piecePriority(piece pieceIndex) piecePriority {
1257 return t.piece(piece).uncachedPriority()
1260 func (t *Torrent) pendRequest(req RequestIndex) {
1261 t.piece(t.pieceIndexOfRequestIndex(req)).pendChunkIndex(req % t.chunksPerRegularPiece())
1264 func (t *Torrent) pieceCompletionChanged(piece pieceIndex, reason string) {
1265 t.cl.event.Broadcast()
1266 if t.pieceComplete(piece) {
1267 t.onPieceCompleted(piece)
1269 t.onIncompletePiece(piece)
1271 t.updatePiecePriority(piece, reason)
1274 func (t *Torrent) numReceivedConns() (ret int) {
1275 for c := range t.conns {
1276 if c.Discovery == PeerSourceIncoming {
1283 func (t *Torrent) maxHalfOpen() int {
1284 // Note that if we somehow exceed the maximum established conns, we want
1285 // the negative value to have an effect.
1286 establishedHeadroom := int64(t.maxEstablishedConns - len(t.conns))
1287 extraIncoming := int64(t.numReceivedConns() - t.maxEstablishedConns/2)
1288 // We want to allow some experimentation with new peers, and to try to
1289 // upset an oversupply of received connections.
1290 return int(min(max(5, extraIncoming)+establishedHeadroom, int64(t.cl.config.HalfOpenConnsPerTorrent)))
1293 func (t *Torrent) openNewConns() (initiated int) {
1294 defer t.updateWantPeersEvent()
1295 for t.peers.Len() != 0 {
1299 if len(t.halfOpen) >= t.maxHalfOpen() {
1302 if len(t.cl.dialers) == 0 {
1305 if t.cl.numHalfOpen >= t.cl.config.TotalHalfOpenConns {
1308 p := t.peers.PopMax()
1315 func (t *Torrent) updatePieceCompletion(piece pieceIndex) bool {
1317 uncached := t.pieceCompleteUncached(piece)
1318 cached := p.completion()
1319 changed := cached != uncached
1320 complete := uncached.Complete
1321 p.storageCompletionOk = uncached.Ok
1324 t._completedPieces.Add(x)
1327 t._completedPieces.Remove(x)
1329 p.t.updatePieceRequestOrder(piece)
1331 if complete && len(p.dirtiers) != 0 {
1332 t.logger.Printf("marked piece %v complete but still has dirtiers", piece)
1335 log.Fstr("piece %d completion changed: %+v -> %+v", piece, cached, uncached).LogLevel(log.Debug, t.logger)
1336 t.pieceCompletionChanged(piece, "Torrent.updatePieceCompletion")
1341 // Non-blocking read. Client lock is not required.
1342 func (t *Torrent) readAt(b []byte, off int64) (n int, err error) {
1344 p := &t.pieces[off/t.info.PieceLength]
1345 p.waitNoPendingWrites()
1347 n1, err = p.Storage().ReadAt(b, off-p.Info().Offset())
1358 // Returns an error if the metadata was completed, but couldn't be set for some reason. Blame it on
1359 // the last peer to contribute. TODO: Actually we shouldn't blame peers for failure to open storage
1360 // etc. Also we should probably cached metadata pieces per-Peer, to isolate failure appropriately.
1361 func (t *Torrent) maybeCompleteMetadata() error {
1366 if !t.haveAllMetadataPieces() {
1367 // Don't have enough metadata pieces.
1370 err := t.setInfoBytesLocked(t.metadataBytes)
1372 t.invalidateMetadata()
1373 return fmt.Errorf("error setting info bytes: %s", err)
1375 if t.cl.config.Debug {
1376 t.logger.Printf("%s: got metadata from peers", t)
1381 func (t *Torrent) readerPiecePriorities() (now, readahead bitmap.Bitmap) {
1382 t.forReaderOffsetPieces(func(begin, end pieceIndex) bool {
1384 now.Add(bitmap.BitIndex(begin))
1385 readahead.AddRange(bitmap.BitRange(begin)+1, bitmap.BitRange(end))
1392 func (t *Torrent) needData() bool {
1393 if t.closed.IsSet() {
1399 return !t._pendingPieces.IsEmpty()
1402 func appendMissingStrings(old, new []string) (ret []string) {
1405 for _, n := range new {
1406 for _, o := range old {
1411 ret = append(ret, n)
1416 func appendMissingTrackerTiers(existing [][]string, minNumTiers int) (ret [][]string) {
1418 for minNumTiers > len(ret) {
1419 ret = append(ret, nil)
1424 func (t *Torrent) addTrackers(announceList [][]string) {
1425 fullAnnounceList := &t.metainfo.AnnounceList
1426 t.metainfo.AnnounceList = appendMissingTrackerTiers(*fullAnnounceList, len(announceList))
1427 for tierIndex, trackerURLs := range announceList {
1428 (*fullAnnounceList)[tierIndex] = appendMissingStrings((*fullAnnounceList)[tierIndex], trackerURLs)
1430 t.startMissingTrackerScrapers()
1431 t.updateWantPeersEvent()
1434 // Don't call this before the info is available.
1435 func (t *Torrent) bytesCompleted() int64 {
1439 return *t.length - t.bytesLeft()
1442 func (t *Torrent) SetInfoBytes(b []byte) (err error) {
1445 return t.setInfoBytesLocked(b)
1448 // Returns true if connection is removed from torrent.Conns.
1449 func (t *Torrent) deletePeerConn(c *PeerConn) (ret bool) {
1450 if !c.closed.IsSet() {
1451 panic("connection is not closed")
1452 // There are behaviours prevented by the closed state that will fail
1453 // if the connection has been deleted.
1457 // Avoid adding a drop event more than once. Probably we should track whether we've generated
1458 // the drop event against the PexConnState instead.
1460 if !t.cl.config.DisablePEX {
1464 torrent.Add("deleted connections", 1)
1465 c.deleteAllRequests("Torrent.deletePeerConn")
1466 t.assertPendingRequests()
1467 if t.numActivePeers() == 0 && len(t.connsWithAllPieces) != 0 {
1468 panic(t.connsWithAllPieces)
1473 func (t *Torrent) decPeerPieceAvailability(p *Peer) {
1474 if t.deleteConnWithAllPieces(p) {
1480 p.peerPieces().Iterate(func(i uint32) bool {
1481 p.t.decPieceAvailability(pieceIndex(i))
1486 func (t *Torrent) assertPendingRequests() {
1490 // var actual pendingRequests
1491 // if t.haveInfo() {
1492 // actual.m = make([]int, t.numRequests())
1494 // t.iterPeers(func(p *Peer) {
1495 // p.requestState.Requests.Iterate(func(x uint32) bool {
1500 // diff := cmp.Diff(actual.m, t.pendingRequests.m)
1506 func (t *Torrent) dropConnection(c *PeerConn) {
1507 t.cl.event.Broadcast()
1509 if t.deletePeerConn(c) {
1514 // Peers as in contact information for dialing out.
1515 func (t *Torrent) wantPeers() bool {
1516 if t.closed.IsSet() {
1519 if t.peers.Len() > t.cl.config.TorrentPeersLowWater {
1522 return t.wantConns()
1525 func (t *Torrent) updateWantPeersEvent() {
1527 t.wantPeersEvent.Set()
1529 t.wantPeersEvent.Clear()
1533 // Returns whether the client should make effort to seed the torrent.
1534 func (t *Torrent) seeding() bool {
1536 if t.closed.IsSet() {
1539 if t.dataUploadDisallowed {
1542 if cl.config.NoUpload {
1545 if !cl.config.Seed {
1548 if cl.config.DisableAggressiveUpload && t.needData() {
1554 func (t *Torrent) onWebRtcConn(
1555 c datachannel.ReadWriteCloser,
1556 dcc webtorrent.DataChannelContext,
1559 netConn := webrtcNetConn{
1561 DataChannelContext: dcc,
1563 peerRemoteAddr := netConn.RemoteAddr()
1564 if t.cl.badPeerAddr(peerRemoteAddr) {
1567 pc, err := t.cl.initiateProtocolHandshakes(
1568 context.Background(),
1573 netConn.RemoteAddr(),
1575 fmt.Sprintf("webrtc offer_id %x: %v", dcc.OfferId, regularNetConnPeerConnConnString(netConn)),
1578 t.logger.WithDefaultLevel(log.Error).Printf("error in handshaking webrtc connection: %v", err)
1581 if dcc.LocalOffered {
1582 pc.Discovery = PeerSourceTracker
1584 pc.Discovery = PeerSourceIncoming
1586 pc.conn.SetWriteDeadline(time.Time{})
1589 err = t.cl.runHandshookConn(pc, t)
1591 t.logger.WithDefaultLevel(log.Critical).Printf("error running handshook webrtc conn: %v", err)
1595 func (t *Torrent) logRunHandshookConn(pc *PeerConn, logAll bool, level log.Level) {
1596 err := t.cl.runHandshookConn(pc, t)
1597 if err != nil || logAll {
1598 t.logger.WithDefaultLevel(level).Printf("error running handshook conn: %v", err)
1602 func (t *Torrent) runHandshookConnLoggingErr(pc *PeerConn) {
1603 t.logRunHandshookConn(pc, false, log.Debug)
1606 func (t *Torrent) startWebsocketAnnouncer(u url.URL) torrentTrackerAnnouncer {
1607 wtc, release := t.cl.websocketTrackers.Get(u.String())
1612 wst := websocketTrackerStatus{u, wtc}
1614 err := wtc.Announce(tracker.Started, t.infoHash)
1616 t.logger.WithDefaultLevel(log.Warning).Printf(
1617 "error in initial announce to %q: %v",
1625 func (t *Torrent) startScrapingTracker(_url string) {
1629 u, err := url.Parse(_url)
1631 // URLs with a leading '*' appear to be a uTorrent convention to
1632 // disable trackers.
1634 log.Str("error parsing tracker url").AddValues("url", _url).Log(t.logger)
1638 if u.Scheme == "udp" {
1640 t.startScrapingTracker(u.String())
1642 t.startScrapingTracker(u.String())
1645 if _, ok := t.trackerAnnouncers[_url]; ok {
1648 sl := func() torrentTrackerAnnouncer {
1651 if t.cl.config.DisableWebtorrent {
1654 return t.startWebsocketAnnouncer(*u)
1656 if t.cl.config.DisableIPv4Peers || t.cl.config.DisableIPv4 {
1660 if t.cl.config.DisableIPv6 {
1664 newAnnouncer := &trackerScraper{
1667 lookupTrackerIp: t.cl.config.LookupTrackerIp,
1669 go newAnnouncer.Run()
1675 if t.trackerAnnouncers == nil {
1676 t.trackerAnnouncers = make(map[string]torrentTrackerAnnouncer)
1678 t.trackerAnnouncers[_url] = sl
1681 // Adds and starts tracker scrapers for tracker URLs that aren't already
1683 func (t *Torrent) startMissingTrackerScrapers() {
1684 if t.cl.config.DisableTrackers {
1687 t.startScrapingTracker(t.metainfo.Announce)
1688 for _, tier := range t.metainfo.AnnounceList {
1689 for _, url := range tier {
1690 t.startScrapingTracker(url)
1695 // Returns an AnnounceRequest with fields filled out to defaults and current
1697 func (t *Torrent) announceRequest(event tracker.AnnounceEvent) tracker.AnnounceRequest {
1698 // Note that IPAddress is not set. It's set for UDP inside the tracker code, since it's
1699 // dependent on the network in use.
1700 return tracker.AnnounceRequest{
1702 NumWant: func() int32 {
1703 if t.wantPeers() && len(t.cl.dialers) > 0 {
1709 Port: uint16(t.cl.incomingPeerPort()),
1710 PeerId: t.cl.peerID,
1711 InfoHash: t.infoHash,
1712 Key: t.cl.announceKey(),
1714 // The following are vaguely described in BEP 3.
1716 Left: t.bytesLeftAnnounce(),
1717 Uploaded: t.stats.BytesWrittenData.Int64(),
1718 // There's no mention of wasted or unwanted download in the BEP.
1719 Downloaded: t.stats.BytesReadUsefulData.Int64(),
1723 // Adds peers revealed in an announce until the announce ends, or we have
1725 func (t *Torrent) consumeDhtAnnouncePeers(pvs <-chan dht.PeersValues) {
1727 for v := range pvs {
1730 for _, cp := range v.Peers {
1732 // Can't do anything with this.
1735 if t.addPeer(PeerInfo{
1736 Addr: ipPortAddr{cp.IP, cp.Port},
1737 Source: PeerSourceDhtGetPeers,
1744 // log.Printf("added %v peers from dht for %v", added, t.InfoHash().HexString())
1749 // Announce using the provided DHT server. Peers are consumed automatically. done is closed when the
1750 // announce ends. stop will force the announce to end.
1751 func (t *Torrent) AnnounceToDht(s DhtServer) (done <-chan struct{}, stop func(), err error) {
1752 ps, err := s.Announce(t.infoHash, t.cl.incomingPeerPort(), true)
1756 _done := make(chan struct{})
1760 t.consumeDhtAnnouncePeers(ps.Peers())
1766 func (t *Torrent) timeboxedAnnounceToDht(s DhtServer) error {
1767 _, stop, err := t.AnnounceToDht(s)
1772 case <-t.closed.Done():
1773 case <-time.After(5 * time.Minute):
1779 func (t *Torrent) dhtAnnouncer(s DhtServer) {
1785 if t.closed.IsSet() {
1788 // We're also announcing ourselves as a listener, so we don't just want peer addresses.
1789 // TODO: We can include the announce_peer step depending on whether we can receive
1790 // inbound connections. We should probably only announce once every 15 mins too.
1794 // TODO: Determine if there's a listener on the port we're announcing.
1795 if len(cl.dialers) == 0 && len(cl.listeners) == 0 {
1806 err := t.timeboxedAnnounceToDht(s)
1808 t.logger.WithDefaultLevel(log.Warning).Printf("error announcing %q to DHT: %s", t, err)
1814 func (t *Torrent) addPeers(peers []PeerInfo) (added int) {
1815 for _, p := range peers {
1823 // The returned TorrentStats may require alignment in memory. See
1824 // https://github.com/anacrolix/torrent/issues/383.
1825 func (t *Torrent) Stats() TorrentStats {
1827 defer t.cl.rUnlock()
1828 return t.statsLocked()
1831 func (t *Torrent) statsLocked() (ret TorrentStats) {
1832 ret.ActivePeers = len(t.conns)
1833 ret.HalfOpenPeers = len(t.halfOpen)
1834 ret.PendingPeers = t.peers.Len()
1835 ret.TotalPeers = t.numTotalPeers()
1836 ret.ConnectedSeeders = 0
1837 for c := range t.conns {
1838 if all, ok := c.peerHasAllPieces(); all && ok {
1839 ret.ConnectedSeeders++
1842 ret.ConnStats = t.stats.Copy()
1843 ret.PiecesComplete = t.numPiecesCompleted()
1847 // The total number of peers in the torrent.
1848 func (t *Torrent) numTotalPeers() int {
1849 peers := make(map[string]struct{})
1850 for conn := range t.conns {
1851 ra := conn.conn.RemoteAddr()
1853 // It's been closed and doesn't support RemoteAddr.
1856 peers[ra.String()] = struct{}{}
1858 for addr := range t.halfOpen {
1859 peers[addr] = struct{}{}
1861 t.peers.Each(func(peer PeerInfo) {
1862 peers[peer.Addr.String()] = struct{}{}
1867 // Reconcile bytes transferred before connection was associated with a
1869 func (t *Torrent) reconcileHandshakeStats(c *PeerConn) {
1870 if c._stats != (ConnStats{
1871 // Handshakes should only increment these fields:
1872 BytesWritten: c._stats.BytesWritten,
1873 BytesRead: c._stats.BytesRead,
1877 c.postHandshakeStats(func(cs *ConnStats) {
1878 cs.BytesRead.Add(c._stats.BytesRead.Int64())
1879 cs.BytesWritten.Add(c._stats.BytesWritten.Int64())
1881 c.reconciledHandshakeStats = true
1884 // Returns true if the connection is added.
1885 func (t *Torrent) addPeerConn(c *PeerConn) (err error) {
1888 torrent.Add("added connections", 1)
1891 if t.closed.IsSet() {
1892 return errors.New("torrent closed")
1894 for c0 := range t.conns {
1895 if c.PeerID != c0.PeerID {
1898 if !t.cl.config.DropDuplicatePeerIds {
1901 if c.hasPreferredNetworkOver(c0) {
1903 t.deletePeerConn(c0)
1905 return errors.New("existing connection preferred")
1908 if len(t.conns) >= t.maxEstablishedConns {
1909 c := t.worstBadConn()
1911 return errors.New("don't want conns")
1916 if len(t.conns) >= t.maxEstablishedConns {
1919 t.conns[c] = struct{}{}
1920 if !t.cl.config.DisablePEX && !c.PeerExtensionBytes.SupportsExtended() {
1921 t.pex.Add(c) // as no further extended handshake expected
1926 func (t *Torrent) wantConns() bool {
1927 if !t.networkingEnabled.Bool() {
1930 if t.closed.IsSet() {
1933 if !t.needData() && (!t.seeding() || !t.haveAnyPieces()) {
1936 return len(t.conns) < t.maxEstablishedConns || t.worstBadConn() != nil
1939 func (t *Torrent) SetMaxEstablishedConns(max int) (oldMax int) {
1942 oldMax = t.maxEstablishedConns
1943 t.maxEstablishedConns = max
1944 wcs := worseConnSlice{
1945 conns: t.appendConns(nil, func(*PeerConn) bool {
1951 for len(t.conns) > t.maxEstablishedConns && wcs.Len() > 0 {
1952 t.dropConnection(heap.Pop(&wcs).(*PeerConn))
1958 func (t *Torrent) pieceHashed(piece pieceIndex, passed bool, hashIoErr error) {
1959 t.logger.LazyLog(log.Debug, func() log.Msg {
1960 return log.Fstr("hashed piece %d (passed=%t)", piece, passed)
1964 t.cl.event.Broadcast()
1965 if t.closed.IsSet() {
1969 // Don't score the first time a piece is hashed, it could be an initial check.
1970 if p.storageCompletionOk {
1972 pieceHashedCorrect.Add(1)
1975 "piece %d failed hash: %d connections contributed", piece, len(p.dirtiers),
1976 ).AddValues(t, p).LogLevel(
1978 log.Debug, t.logger)
1980 pieceHashedNotCorrect.Add(1)
1985 t.publishPieceChange(piece)
1988 t.publishPieceChange(piece)
1992 if len(p.dirtiers) != 0 {
1993 // Don't increment stats above connection-level for every involved connection.
1994 t.allStats((*ConnStats).incrementPiecesDirtiedGood)
1996 for c := range p.dirtiers {
1997 c._stats.incrementPiecesDirtiedGood()
1999 t.clearPieceTouchers(piece)
2001 err := p.Storage().MarkComplete()
2003 t.logger.Printf("%T: error marking piece complete %d: %s", t.storage, piece, err)
2007 if t.closed.IsSet() {
2010 t.pendAllChunkSpecs(piece)
2012 if len(p.dirtiers) != 0 && p.allChunksDirty() && hashIoErr == nil {
2013 // Peers contributed to all the data for this piece hash failure, and the failure was
2014 // not due to errors in the storage (such as data being dropped in a cache).
2016 // Increment Torrent and above stats, and then specific connections.
2017 t.allStats((*ConnStats).incrementPiecesDirtiedBad)
2018 for c := range p.dirtiers {
2019 // Y u do dis peer?!
2020 c.stats().incrementPiecesDirtiedBad()
2023 bannableTouchers := make([]*Peer, 0, len(p.dirtiers))
2024 for c := range p.dirtiers {
2026 bannableTouchers = append(bannableTouchers, c)
2029 t.clearPieceTouchers(piece)
2030 slices.Sort(bannableTouchers, connLessTrusted)
2032 if t.cl.config.Debug {
2034 "bannable conns by trust for piece %d: %v",
2036 func() (ret []connectionTrust) {
2037 for _, c := range bannableTouchers {
2038 ret = append(ret, c.trust())
2045 if len(bannableTouchers) >= 1 {
2046 c := bannableTouchers[0]
2047 if len(bannableTouchers) != 1 {
2048 t.logger.Levelf(log.Warning, "would have banned %v for touching piece %v after failed piece check", c.remoteIp(), piece)
2050 // Turns out it's still useful to ban peers like this because if there's only a
2051 // single peer for a piece, and we never progress that piece to completion, we
2052 // will never smart-ban them. Discovered in
2053 // https://github.com/anacrolix/torrent/issues/715.
2054 t.logger.Levelf(log.Warning, "banning %v for being sole dirtier of piece %v after failed piece check", c, piece)
2059 t.onIncompletePiece(piece)
2060 p.Storage().MarkNotComplete()
2062 t.updatePieceCompletion(piece)
2065 func (t *Torrent) cancelRequestsForPiece(piece pieceIndex) {
2066 for ri := t.pieceRequestIndexOffset(piece); ri < t.pieceRequestIndexOffset(piece+1); ri++ {
2071 func (t *Torrent) onPieceCompleted(piece pieceIndex) {
2072 t.pendAllChunkSpecs(piece)
2073 t.cancelRequestsForPiece(piece)
2074 t.piece(piece).readerCond.Broadcast()
2075 for conn := range t.conns {
2077 t.maybeDropMutuallyCompletePeer(&conn.Peer)
2081 // Called when a piece is found to be not complete.
2082 func (t *Torrent) onIncompletePiece(piece pieceIndex) {
2083 if t.pieceAllDirty(piece) {
2084 t.pendAllChunkSpecs(piece)
2086 if !t.wantPieceIndex(piece) {
2087 // t.logger.Printf("piece %d incomplete and unwanted", piece)
2090 // We could drop any connections that we told we have a piece that we
2091 // don't here. But there's a test failure, and it seems clients don't care
2092 // if you request pieces that you already claim to have. Pruning bad
2093 // connections might just remove any connections that aren't treating us
2094 // favourably anyway.
2096 // for c := range t.conns {
2097 // if c.sentHave(piece) {
2101 t.iterPeers(func(conn *Peer) {
2102 if conn.peerHasPiece(piece) {
2103 conn.updateRequests("piece incomplete")
2108 func (t *Torrent) tryCreateMorePieceHashers() {
2109 for !t.closed.IsSet() && t.activePieceHashes < 2 && t.tryCreatePieceHasher() {
2113 func (t *Torrent) tryCreatePieceHasher() bool {
2114 if t.storage == nil {
2117 pi, ok := t.getPieceToHash()
2122 t.piecesQueuedForHash.Remove(bitmap.BitIndex(pi))
2124 t.publishPieceChange(pi)
2125 t.updatePiecePriority(pi, "Torrent.tryCreatePieceHasher")
2126 t.storageLock.RLock()
2127 t.activePieceHashes++
2128 go t.pieceHasher(pi)
2132 func (t *Torrent) getPieceToHash() (ret pieceIndex, ok bool) {
2133 t.piecesQueuedForHash.IterTyped(func(i pieceIndex) bool {
2134 if t.piece(i).hashing {
2144 func (t *Torrent) dropBannedPeers() {
2145 t.iterPeers(func(p *Peer) {
2146 remoteIp := p.remoteIp()
2147 if remoteIp == nil {
2148 if p.bannableAddr.Ok() {
2149 t.logger.WithDefaultLevel(log.Debug).Printf("can't get remote ip for peer %v", p)
2153 netipAddr := netip.MustParseAddr(remoteIp.String())
2154 if Some(netipAddr) != p.bannableAddr {
2155 t.logger.WithDefaultLevel(log.Debug).Printf(
2156 "peer remote ip does not match its bannable addr [peer=%v, remote ip=%v, bannable addr=%v]",
2157 p, remoteIp, p.bannableAddr)
2159 if _, ok := t.cl.badPeerIPs[netipAddr]; ok {
2160 // Should this be a close?
2162 t.logger.WithDefaultLevel(log.Debug).Printf("dropped %v for banned remote IP %v", p, netipAddr)
2167 func (t *Torrent) pieceHasher(index pieceIndex) {
2169 sum, failedPeers, copyErr := t.hashPiece(index)
2170 correct := sum == *p.hash
2174 log.Fmsg("piece %v (%s) hash failure copy error: %v", p, p.hash.HexString(), copyErr).Log(t.logger)
2176 t.storageLock.RUnlock()
2180 for peer := range failedPeers {
2181 t.cl.banPeerIP(peer.AsSlice())
2182 t.logger.WithDefaultLevel(log.Debug).Printf("smart banned %v for piece %v", peer, index)
2185 for ri := t.pieceRequestIndexOffset(index); ri < t.pieceRequestIndexOffset(index+1); ri++ {
2186 t.smartBanCache.ForgetBlock(ri)
2190 t.pieceHashed(index, correct, copyErr)
2191 t.updatePiecePriority(index, "Torrent.pieceHasher")
2192 t.activePieceHashes--
2193 t.tryCreateMorePieceHashers()
2196 // Return the connections that touched a piece, and clear the entries while doing it.
2197 func (t *Torrent) clearPieceTouchers(pi pieceIndex) {
2199 for c := range p.dirtiers {
2200 delete(c.peerTouchedPieces, pi)
2201 delete(p.dirtiers, c)
2205 func (t *Torrent) peersAsSlice() (ret []*Peer) {
2206 t.iterPeers(func(p *Peer) {
2207 ret = append(ret, p)
2212 func (t *Torrent) queuePieceCheck(pieceIndex pieceIndex) {
2213 piece := t.piece(pieceIndex)
2214 if piece.queuedForHash() {
2217 t.piecesQueuedForHash.Add(bitmap.BitIndex(pieceIndex))
2218 t.publishPieceChange(pieceIndex)
2219 t.updatePiecePriority(pieceIndex, "Torrent.queuePieceCheck")
2220 t.tryCreateMorePieceHashers()
2223 // Forces all the pieces to be re-hashed. See also Piece.VerifyData. This should not be called
2224 // before the Info is available.
2225 func (t *Torrent) VerifyData() {
2226 for i := pieceIndex(0); i < t.NumPieces(); i++ {
2227 t.Piece(i).VerifyData()
2231 // Start the process of connecting to the given peer for the given torrent if appropriate.
2232 func (t *Torrent) initiateConn(peer PeerInfo) {
2233 if peer.Id == t.cl.peerID {
2236 if t.cl.badPeerAddr(peer.Addr) && !peer.Trusted {
2240 if t.addrActive(addr.String()) {
2244 t.halfOpen[addr.String()] = peer
2245 go t.cl.outgoingConnection(t, addr, peer.Source, peer.Trusted)
2248 // Adds a trusted, pending peer for each of the given Client's addresses. Typically used in tests to
2249 // quickly make one Client visible to the Torrent of another Client.
2250 func (t *Torrent) AddClientPeer(cl *Client) int {
2251 return t.AddPeers(func() (ps []PeerInfo) {
2252 for _, la := range cl.ListenAddrs() {
2253 ps = append(ps, PeerInfo{
2262 // All stats that include this Torrent. Useful when we want to increment ConnStats but not for every
2264 func (t *Torrent) allStats(f func(*ConnStats)) {
2269 func (t *Torrent) hashingPiece(i pieceIndex) bool {
2270 return t.pieces[i].hashing
2273 func (t *Torrent) pieceQueuedForHash(i pieceIndex) bool {
2274 return t.piecesQueuedForHash.Get(bitmap.BitIndex(i))
2277 func (t *Torrent) dialTimeout() time.Duration {
2278 return reducedDialTimeout(t.cl.config.MinDialTimeout, t.cl.config.NominalDialTimeout, t.cl.config.HalfOpenConnsPerTorrent, t.peers.Len())
2281 func (t *Torrent) piece(i int) *Piece {
2285 func (t *Torrent) onWriteChunkErr(err error) {
2286 if t.userOnWriteChunkErr != nil {
2287 go t.userOnWriteChunkErr(err)
2290 t.logger.WithDefaultLevel(log.Critical).Printf("default chunk write error handler: disabling data download")
2291 t.disallowDataDownloadLocked()
2294 func (t *Torrent) DisallowDataDownload() {
2295 t.disallowDataDownloadLocked()
2298 func (t *Torrent) disallowDataDownloadLocked() {
2299 t.dataDownloadDisallowed.Set()
2302 func (t *Torrent) AllowDataDownload() {
2303 t.dataDownloadDisallowed.Clear()
2306 // Enables uploading data, if it was disabled.
2307 func (t *Torrent) AllowDataUpload() {
2310 t.dataUploadDisallowed = false
2311 for c := range t.conns {
2312 c.updateRequests("allow data upload")
2316 // Disables uploading data, if it was enabled.
2317 func (t *Torrent) DisallowDataUpload() {
2320 t.dataUploadDisallowed = true
2321 for c := range t.conns {
2322 // TODO: This doesn't look right. Shouldn't we tickle writers to choke peers or something instead?
2323 c.updateRequests("disallow data upload")
2327 // Sets a handler that is called if there's an error writing a chunk to local storage. By default,
2328 // or if nil, a critical message is logged, and data download is disabled.
2329 func (t *Torrent) SetOnWriteChunkError(f func(error)) {
2332 t.userOnWriteChunkErr = f
2335 func (t *Torrent) iterPeers(f func(p *Peer)) {
2336 for pc := range t.conns {
2339 for _, ws := range t.webSeeds {
2344 func (t *Torrent) callbacks() *Callbacks {
2345 return &t.cl.config.Callbacks
2348 type AddWebSeedsOpt func(*webseed.Client)
2350 // Sets the WebSeed trailing path escaper for a webseed.Client.
2351 func WebSeedPathEscaper(custom webseed.PathEscaper) AddWebSeedsOpt {
2352 return func(c *webseed.Client) {
2353 c.PathEscaper = custom
2357 func (t *Torrent) AddWebSeeds(urls []string, opts ...AddWebSeedsOpt) {
2360 for _, u := range urls {
2361 t.addWebSeed(u, opts...)
2365 func (t *Torrent) addWebSeed(url string, opts ...AddWebSeedsOpt) {
2366 if t.cl.config.DisableWebseeds {
2369 if _, ok := t.webSeeds[url]; ok {
2372 // I don't think Go http supports pipelining requests. However, we can have more ready to go
2373 // right away. This value should be some multiple of the number of connections to a host. I
2374 // would expect that double maxRequests plus a bit would be appropriate. This value is based on
2375 // downloading Sintel (08ada5a7a6183aae1e09d831df6748d566095a10) from
2376 // "https://webtorrent.io/torrents/".
2377 const maxRequests = 16
2383 reconciledHandshakeStats: true,
2384 // This should affect how often we have to recompute requests for this peer. Note that
2385 // because we can request more than 1 thing at a time over HTTP, we will hit the low
2386 // requests mark more often, so recomputation is probably sooner than with regular peer
2387 // conns. ~4x maxRequests would be about right.
2388 PeerMaxRequests: 128,
2389 // TODO: Set ban prefix?
2390 RemoteAddr: remoteAddrFromUrl(url),
2391 callbacks: t.callbacks(),
2393 client: webseed.Client{
2394 HttpClient: t.cl.httpClient,
2396 ResponseBodyWrapper: func(r io.Reader) io.Reader {
2397 return &rateLimitedReader{
2398 l: t.cl.config.DownloadRateLimiter,
2403 activeRequests: make(map[Request]webseed.Request, maxRequests),
2404 maxRequests: maxRequests,
2406 ws.peer.initRequestState()
2407 for _, opt := range opts {
2410 ws.peer.initUpdateRequestsTimer()
2411 ws.requesterCond.L = t.cl.locker()
2412 for i := 0; i < maxRequests; i += 1 {
2415 for _, f := range t.callbacks().NewPeer {
2418 ws.peer.logger = t.logger.WithContextValue(&ws)
2419 ws.peer.peerImpl = &ws
2421 ws.onGotInfo(t.info)
2423 t.webSeeds[url] = &ws.peer
2426 func (t *Torrent) peerIsActive(p *Peer) (active bool) {
2427 t.iterPeers(func(p1 *Peer) {
2435 func (t *Torrent) requestIndexToRequest(ri RequestIndex) Request {
2436 index := t.pieceIndexOfRequestIndex(ri)
2439 t.piece(index).chunkIndexSpec(ri % t.chunksPerRegularPiece()),
2443 func (t *Torrent) requestIndexFromRequest(r Request) RequestIndex {
2444 return t.pieceRequestIndexOffset(pieceIndex(r.Index)) + RequestIndex(r.Begin/t.chunkSize)
2447 func (t *Torrent) pieceRequestIndexOffset(piece pieceIndex) RequestIndex {
2448 return RequestIndex(piece) * t.chunksPerRegularPiece()
2451 func (t *Torrent) updateComplete() {
2452 t.Complete.SetBool(t.haveAllPieces())
2455 func (t *Torrent) cancelRequest(r RequestIndex) *Peer {
2456 p := t.pendingRequests[r]
2460 delete(t.pendingRequests, r)
2464 func (t *Torrent) requestingPeer(r RequestIndex) *Peer {
2465 return t.pendingRequests[r]
2468 func (t *Torrent) addConnWithAllPieces(p *Peer) {
2469 if t.connsWithAllPieces == nil {
2470 t.connsWithAllPieces = make(map[*Peer]struct{}, t.maxEstablishedConns)
2472 t.connsWithAllPieces[p] = struct{}{}
2475 func (t *Torrent) deleteConnWithAllPieces(p *Peer) bool {
2476 _, ok := t.connsWithAllPieces[p]
2477 delete(t.connsWithAllPieces, p)
2481 func (t *Torrent) numActivePeers() int {
2482 return len(t.conns) + len(t.webSeeds)
2485 func (t *Torrent) hasStorageCap() bool {
2486 f := t.storage.Capacity
2494 func (t *Torrent) pieceIndexOfRequestIndex(ri RequestIndex) pieceIndex {
2495 return pieceIndex(ri / t.chunksPerRegularPiece())