20 "github.com/RoaringBitmap/roaring"
21 "github.com/anacrolix/chansync"
22 "github.com/anacrolix/chansync/events"
23 "github.com/anacrolix/dht/v2"
24 . "github.com/anacrolix/generics"
25 "github.com/anacrolix/log"
26 "github.com/anacrolix/missinggo/perf"
27 "github.com/anacrolix/missinggo/slices"
28 "github.com/anacrolix/missinggo/v2"
29 "github.com/anacrolix/missinggo/v2/bitmap"
30 "github.com/anacrolix/missinggo/v2/pubsub"
31 "github.com/anacrolix/multiless"
32 "github.com/anacrolix/sync"
33 "github.com/davecgh/go-spew/spew"
34 "github.com/pion/datachannel"
36 "github.com/anacrolix/torrent/bencode"
37 "github.com/anacrolix/torrent/common"
38 "github.com/anacrolix/torrent/metainfo"
39 pp "github.com/anacrolix/torrent/peer_protocol"
40 request_strategy "github.com/anacrolix/torrent/request-strategy"
41 "github.com/anacrolix/torrent/segments"
42 "github.com/anacrolix/torrent/storage"
43 "github.com/anacrolix/torrent/tracker"
44 typedRoaring "github.com/anacrolix/torrent/typed-roaring"
45 "github.com/anacrolix/torrent/webseed"
46 "github.com/anacrolix/torrent/webtorrent"
49 // Maintains state of torrent within a Client. Many methods should not be called before the info is
50 // available, see .Info and .GotInfo.
52 // Torrent-level aggregate statistics. First in struct to ensure 64-bit
53 // alignment. See #262.
58 networkingEnabled chansync.Flag
59 dataDownloadDisallowed chansync.Flag
60 dataUploadDisallowed bool
61 userOnWriteChunkErr func(error)
63 closed chansync.SetOnce
65 infoHash metainfo.Hash
68 // The order pieces are requested if there's no stronger reason like availability or priority.
69 pieceRequestOrder []int
70 // Values are the piece indices that changed.
71 pieceStateChanges pubsub.PubSub[PieceStateChange]
72 // The size of chunks to request from peers over the wire. This is
73 // normally 16KiB by convention these days.
76 // Total length of the torrent in bytes. Stored because it's not O(1) to
77 // get this from the info dict.
80 // The storage to open when the info dict becomes available.
81 storageOpener *storage.Client
82 // Storage for torrent data.
83 storage *storage.Torrent
84 // Read-locked for using storage, and write-locked for Closing.
85 storageLock sync.RWMutex
87 // TODO: Only announce stuff is used?
88 metainfo metainfo.MetaInfo
90 // The info dict. nil if we don't have it (yet).
92 fileIndex segments.Index
95 _chunksPerRegularPiece chunkIndexType
97 webSeeds map[string]*Peer
98 // Active peer connections, running message stream loops. TODO: Make this
99 // open (not-closed) connections only.
100 conns map[*PeerConn]struct{}
101 maxEstablishedConns int
102 // Set of addrs to which we're attempting to connect. Connections are
103 // half-open until all handshakes are completed.
104 halfOpen map[string]PeerInfo
106 // Reserve of peers to connect to. A peer can be both here and in the
107 // active connections if were told about the peer after connecting with
108 // them. That encourages us to reconnect to peers that are well known in
110 peers prioritizedPeers
111 // Whether we want to know more peers.
112 wantPeersEvent missinggo.Event
113 // An announcer for each tracker URL.
114 trackerAnnouncers map[string]torrentTrackerAnnouncer
115 // How many times we've initiated a DHT announce. TODO: Move into stats.
118 // Name used if the info name isn't available. Should be cleared when the
119 // Info does become available.
123 // The bencoded bytes of the info dict. This is actively manipulated if
124 // the info bytes aren't initially available, and we try to fetch them
127 // Each element corresponds to the 16KiB metadata pieces. If true, we have
128 // received that piece.
129 metadataCompletedChunks []bool
130 metadataChanged sync.Cond
132 // Closed when .Info is obtained.
133 gotMetainfoC chan struct{}
135 readers map[*reader]struct{}
136 _readerNowPieces bitmap.Bitmap
137 _readerReadaheadPieces bitmap.Bitmap
139 // A cache of pieces we need to get. Calculated from various piece and
140 // file priorities and completion states elsewhere.
141 _pendingPieces roaring.Bitmap
142 // A cache of completed piece indices.
143 _completedPieces roaring.Bitmap
144 // Pieces that need to be hashed.
145 piecesQueuedForHash bitmap.Bitmap
146 activePieceHashes int
147 initialPieceCheckDisabled bool
149 connsWithAllPieces map[*Peer]struct{}
151 requestState map[RequestIndex]requestState
152 // Chunks we've written to since the corresponding piece was last checked.
153 dirtyChunks typedRoaring.Bitmap[RequestIndex]
157 // Is On when all pieces are complete.
158 Complete chansync.Flag
160 // Torrent sources in use keyed by the source string.
161 activeSources sync.Map
162 sourcesLogger log.Logger
164 smartBanCache smartBanCache
166 // Large allocations reused between request state updates.
167 requestPieceStates []request_strategy.PieceRequestOrderState
168 requestIndexes []RequestIndex
171 func (t *Torrent) length() int64 {
172 return t._length.Value
175 func (t *Torrent) selectivePieceAvailabilityFromPeers(i pieceIndex) (count int) {
176 // This could be done with roaring.BitSliceIndexing.
177 t.iterPeers(func(peer *Peer) {
178 if _, ok := t.connsWithAllPieces[peer]; ok {
181 if peer.peerHasPiece(i) {
188 func (t *Torrent) decPieceAvailability(i pieceIndex) {
193 if p.relativeAvailability <= 0 {
194 panic(p.relativeAvailability)
196 p.relativeAvailability--
197 t.updatePieceRequestOrder(i)
200 func (t *Torrent) incPieceAvailability(i pieceIndex) {
201 // If we don't the info, this should be reconciled when we do.
204 p.relativeAvailability++
205 t.updatePieceRequestOrder(i)
209 func (t *Torrent) readerNowPieces() bitmap.Bitmap {
210 return t._readerNowPieces
213 func (t *Torrent) readerReadaheadPieces() bitmap.Bitmap {
214 return t._readerReadaheadPieces
217 func (t *Torrent) ignorePieceForRequests(i pieceIndex) bool {
218 return !t.wantPieceIndex(i)
221 // Returns a channel that is closed when the Torrent is closed.
222 func (t *Torrent) Closed() events.Done {
223 return t.closed.Done()
226 // KnownSwarm returns the known subset of the peers in the Torrent's swarm, including active,
227 // pending, and half-open peers.
228 func (t *Torrent) KnownSwarm() (ks []PeerInfo) {
229 // Add pending peers to the list
230 t.peers.Each(func(peer PeerInfo) {
231 ks = append(ks, peer)
234 // Add half-open peers to the list
235 for _, peer := range t.halfOpen {
236 ks = append(ks, peer)
239 // Add active peers to the list
240 for conn := range t.conns {
241 ks = append(ks, PeerInfo{
243 Addr: conn.RemoteAddr,
244 Source: conn.Discovery,
245 // > If the connection is encrypted, that's certainly enough to set SupportsEncryption.
246 // > But if we're not connected to them with an encrypted connection, I couldn't say
247 // > what's appropriate. We can carry forward the SupportsEncryption value as we
248 // > received it from trackers/DHT/PEX, or just use the encryption state for the
249 // > connection. It's probably easiest to do the latter for now.
250 // https://github.com/anacrolix/torrent/pull/188
251 SupportsEncryption: conn.headerEncrypted,
258 func (t *Torrent) setChunkSize(size pp.Integer) {
260 t.chunkPool = sync.Pool{
261 New: func() interface{} {
262 b := make([]byte, size)
268 func (t *Torrent) pieceComplete(piece pieceIndex) bool {
269 return t._completedPieces.Contains(bitmap.BitIndex(piece))
272 func (t *Torrent) pieceCompleteUncached(piece pieceIndex) storage.Completion {
273 if t.storage == nil {
274 return storage.Completion{Complete: false, Ok: true}
276 return t.pieces[piece].Storage().Completion()
279 // There's a connection to that address already.
280 func (t *Torrent) addrActive(addr string) bool {
281 if _, ok := t.halfOpen[addr]; ok {
284 for c := range t.conns {
286 if ra.String() == addr {
293 func (t *Torrent) appendUnclosedConns(ret []*PeerConn) []*PeerConn {
294 return t.appendConns(ret, func(conn *PeerConn) bool {
295 return !conn.closed.IsSet()
299 func (t *Torrent) appendConns(ret []*PeerConn, f func(*PeerConn) bool) []*PeerConn {
300 for c := range t.conns {
308 func (t *Torrent) addPeer(p PeerInfo) (added bool) {
310 torrent.Add(fmt.Sprintf("peers added by source %q", p.Source), 1)
311 if t.closed.IsSet() {
314 if ipAddr, ok := tryIpPortFromNetAddr(p.Addr); ok {
315 if cl.badPeerIPPort(ipAddr.IP, ipAddr.Port) {
316 torrent.Add("peers not added because of bad addr", 1)
317 // cl.logger.Printf("peers not added because of bad addr: %v", p)
321 if replaced, ok := t.peers.AddReturningReplacedPeer(p); ok {
322 torrent.Add("peers replaced", 1)
323 if !replaced.equal(p) {
324 t.logger.WithDefaultLevel(log.Debug).Printf("added %v replacing %v", p, replaced)
331 for t.peers.Len() > cl.config.TorrentPeersHighWater {
332 _, ok := t.peers.DeleteMin()
334 torrent.Add("excess reserve peers discarded", 1)
340 func (t *Torrent) invalidateMetadata() {
341 for i := 0; i < len(t.metadataCompletedChunks); i++ {
342 t.metadataCompletedChunks[i] = false
345 t.gotMetainfoC = make(chan struct{})
350 func (t *Torrent) saveMetadataPiece(index int, data []byte) {
354 if index >= len(t.metadataCompletedChunks) {
355 t.logger.Printf("%s: ignoring metadata piece %d", t, index)
358 copy(t.metadataBytes[(1<<14)*index:], data)
359 t.metadataCompletedChunks[index] = true
362 func (t *Torrent) metadataPieceCount() int {
363 return (len(t.metadataBytes) + (1 << 14) - 1) / (1 << 14)
366 func (t *Torrent) haveMetadataPiece(piece int) bool {
368 return (1<<14)*piece < len(t.metadataBytes)
370 return piece < len(t.metadataCompletedChunks) && t.metadataCompletedChunks[piece]
374 func (t *Torrent) metadataSize() int {
375 return len(t.metadataBytes)
378 func infoPieceHashes(info *metainfo.Info) (ret [][]byte) {
379 for i := 0; i < len(info.Pieces); i += sha1.Size {
380 ret = append(ret, info.Pieces[i:i+sha1.Size])
385 func (t *Torrent) makePieces() {
386 hashes := infoPieceHashes(t.info)
387 t.pieces = make([]Piece, len(hashes))
388 for i, hash := range hashes {
389 piece := &t.pieces[i]
391 piece.index = pieceIndex(i)
392 piece.noPendingWrites.L = &piece.pendingWritesMutex
393 piece.hash = (*metainfo.Hash)(unsafe.Pointer(&hash[0]))
395 beginFile := pieceFirstFileIndex(piece.torrentBeginOffset(), files)
396 endFile := pieceEndFileIndex(piece.torrentEndOffset(), files)
397 piece.files = files[beginFile:endFile]
401 // Returns the index of the first file containing the piece. files must be
402 // ordered by offset.
403 func pieceFirstFileIndex(pieceOffset int64, files []*File) int {
404 for i, f := range files {
405 if f.offset+f.length > pieceOffset {
412 // Returns the index after the last file containing the piece. files must be
413 // ordered by offset.
414 func pieceEndFileIndex(pieceEndOffset int64, files []*File) int {
415 for i, f := range files {
416 if f.offset+f.length >= pieceEndOffset {
423 func (t *Torrent) cacheLength() {
425 for _, f := range t.info.UpvertedFiles() {
431 // TODO: This shouldn't fail for storage reasons. Instead we should handle storage failure
433 func (t *Torrent) setInfo(info *metainfo.Info) error {
434 if err := validateInfo(info); err != nil {
435 return fmt.Errorf("bad info: %s", err)
437 if t.storageOpener != nil {
439 t.storage, err = t.storageOpener.OpenTorrent(info, t.infoHash)
441 return fmt.Errorf("error opening torrent storage: %s", err)
447 t._chunksPerRegularPiece = chunkIndexType((pp.Integer(t.usualPieceSize()) + t.chunkSize - 1) / t.chunkSize)
449 t.fileIndex = segments.NewIndex(common.LengthIterFromUpvertedFiles(info.UpvertedFiles()))
450 t.displayName = "" // Save a few bytes lol.
457 func (t *Torrent) pieceRequestOrderKey(i int) request_strategy.PieceRequestOrderKey {
458 return request_strategy.PieceRequestOrderKey{
459 InfoHash: t.infoHash,
464 // This seems to be all the follow-up tasks after info is set, that can't fail.
465 func (t *Torrent) onSetInfo() {
466 t.pieceRequestOrder = rand.Perm(t.numPieces())
467 t.initPieceRequestOrder()
468 MakeSliceWithLength(&t.requestPieceStates, t.numPieces())
469 for i := range t.pieces {
471 // Need to add relativeAvailability before updating piece completion, as that may result in conns
473 if p.relativeAvailability != 0 {
474 panic(p.relativeAvailability)
476 p.relativeAvailability = t.selectivePieceAvailabilityFromPeers(i)
477 t.addRequestOrderPiece(i)
478 t.updatePieceCompletion(i)
479 if !t.initialPieceCheckDisabled && !p.storageCompletionOk {
480 // t.logger.Printf("piece %s completion unknown, queueing check", p)
484 t.cl.event.Broadcast()
485 close(t.gotMetainfoC)
486 t.updateWantPeersEvent()
487 t.requestState = make(map[RequestIndex]requestState)
488 t.tryCreateMorePieceHashers()
489 t.iterPeers(func(p *Peer) {
491 p.updateRequests("onSetInfo")
495 // Called when metadata for a torrent becomes available.
496 func (t *Torrent) setInfoBytesLocked(b []byte) error {
497 if metainfo.HashBytes(b) != t.infoHash {
498 return errors.New("info bytes have wrong hash")
500 var info metainfo.Info
501 if err := bencode.Unmarshal(b, &info); err != nil {
502 return fmt.Errorf("error unmarshalling info bytes: %s", err)
505 t.metadataCompletedChunks = nil
509 if err := t.setInfo(&info); err != nil {
516 func (t *Torrent) haveAllMetadataPieces() bool {
520 if t.metadataCompletedChunks == nil {
523 for _, have := range t.metadataCompletedChunks {
531 // TODO: Propagate errors to disconnect peer.
532 func (t *Torrent) setMetadataSize(size int) (err error) {
534 // We already know the correct metadata size.
537 if uint32(size) > maxMetadataSize {
538 return log.WithLevel(log.Warning, errors.New("bad size"))
540 if len(t.metadataBytes) == size {
543 t.metadataBytes = make([]byte, size)
544 t.metadataCompletedChunks = make([]bool, (size+(1<<14)-1)/(1<<14))
545 t.metadataChanged.Broadcast()
546 for c := range t.conns {
547 c.requestPendingMetadata()
552 // The current working name for the torrent. Either the name in the info dict,
553 // or a display name given such as by the dn value in a magnet link, or "".
554 func (t *Torrent) name() string {
556 defer t.nameMu.RUnlock()
558 return t.info.BestName()
560 if t.displayName != "" {
563 return "infohash:" + t.infoHash.HexString()
566 func (t *Torrent) pieceState(index pieceIndex) (ret PieceState) {
567 p := &t.pieces[index]
568 ret.Priority = t.piecePriority(index)
569 ret.Completion = p.completion()
570 ret.QueuedForHash = p.queuedForHash()
571 ret.Hashing = p.hashing
572 ret.Checking = ret.QueuedForHash || ret.Hashing
573 ret.Marking = p.marking
574 if !ret.Complete && t.piecePartiallyDownloaded(index) {
580 func (t *Torrent) metadataPieceSize(piece int) int {
581 return metadataPieceSize(len(t.metadataBytes), piece)
584 func (t *Torrent) newMetadataExtensionMessage(c *PeerConn, msgType pp.ExtendedMetadataRequestMsgType, piece int, data []byte) pp.Message {
587 ExtendedID: c.PeerExtensionIDs[pp.ExtensionNameMetadata],
588 ExtendedPayload: append(bencode.MustMarshal(pp.ExtendedMetadataRequestMsg{
590 TotalSize: len(t.metadataBytes),
596 type pieceAvailabilityRun struct {
601 func (me pieceAvailabilityRun) String() string {
602 return fmt.Sprintf("%v(%v)", me.Count, me.Availability)
605 func (t *Torrent) pieceAvailabilityRuns() (ret []pieceAvailabilityRun) {
606 rle := missinggo.NewRunLengthEncoder(func(el interface{}, count uint64) {
607 ret = append(ret, pieceAvailabilityRun{Availability: el.(int), Count: int(count)})
609 for i := range t.pieces {
610 rle.Append(t.pieces[i].availability(), 1)
616 func (t *Torrent) pieceAvailabilityFrequencies() (freqs []int) {
617 freqs = make([]int, t.numActivePeers()+1)
618 for i := range t.pieces {
619 freqs[t.piece(i).availability()]++
624 func (t *Torrent) pieceStateRuns() (ret PieceStateRuns) {
625 rle := missinggo.NewRunLengthEncoder(func(el interface{}, count uint64) {
626 ret = append(ret, PieceStateRun{
627 PieceState: el.(PieceState),
631 for index := range t.pieces {
632 rle.Append(t.pieceState(pieceIndex(index)), 1)
638 // Produces a small string representing a PieceStateRun.
639 func (psr PieceStateRun) String() (ret string) {
640 ret = fmt.Sprintf("%d", psr.Length)
641 ret += func() string {
642 switch psr.Priority {
643 case PiecePriorityNext:
645 case PiecePriorityNormal:
647 case PiecePriorityReadahead:
649 case PiecePriorityNow:
651 case PiecePriorityHigh:
660 if psr.QueuedForHash {
678 func (t *Torrent) writeStatus(w io.Writer) {
679 fmt.Fprintf(w, "Infohash: %s\n", t.infoHash.HexString())
680 fmt.Fprintf(w, "Metadata length: %d\n", t.metadataSize())
682 fmt.Fprintf(w, "Metadata have: ")
683 for _, h := range t.metadataCompletedChunks {
684 fmt.Fprintf(w, "%c", func() rune {
694 fmt.Fprintf(w, "Piece length: %s\n",
697 return fmt.Sprintf("%v (%v chunks)",
699 float64(t.usualPieceSize())/float64(t.chunkSize))
706 fmt.Fprintf(w, "Num Pieces: %d (%d completed)\n", t.numPieces(), t.numPiecesCompleted())
707 fmt.Fprintf(w, "Piece States: %s\n", t.pieceStateRuns())
708 // Generates a huge, unhelpful listing when piece availability is very scattered. Prefer
709 // availability frequencies instead.
711 fmt.Fprintf(w, "Piece availability: %v\n", strings.Join(func() (ret []string) {
712 for _, run := range t.pieceAvailabilityRuns() {
713 ret = append(ret, run.String())
718 fmt.Fprintf(w, "Piece availability frequency: %v\n", strings.Join(
719 func() (ret []string) {
720 for avail, freq := range t.pieceAvailabilityFrequencies() {
724 ret = append(ret, fmt.Sprintf("%v: %v", avail, freq))
730 fmt.Fprintf(w, "Reader Pieces:")
731 t.forReaderOffsetPieces(func(begin, end pieceIndex) (again bool) {
732 fmt.Fprintf(w, " %d:%d", begin, end)
737 fmt.Fprintf(w, "Enabled trackers:\n")
739 tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', 0)
740 fmt.Fprintf(tw, " URL\tExtra\n")
741 for _, ta := range slices.Sort(slices.FromMapElems(t.trackerAnnouncers), func(l, r torrentTrackerAnnouncer) bool {
744 var luns, runs url.URL = *lu, *ru
747 var ml missinggo.MultiLess
748 ml.StrictNext(luns.String() == runs.String(), luns.String() < runs.String())
749 ml.StrictNext(lu.String() == ru.String(), lu.String() < ru.String())
751 }).([]torrentTrackerAnnouncer) {
752 fmt.Fprintf(tw, " %q\t%v\n", ta.URL(), ta.statusLine())
757 fmt.Fprintf(w, "DHT Announces: %d\n", t.numDHTAnnounces)
759 spew.NewDefaultConfig()
760 spew.Fdump(w, t.statsLocked())
762 peers := t.peersAsSlice()
763 sort.Slice(peers, func(_i, _j int) bool {
766 if less, ok := multiless.New().EagerSameLess(
767 i.downloadRate() == j.downloadRate(), i.downloadRate() < j.downloadRate(),
771 return worseConn(i, j)
774 for i, c := range peers {
775 fmt.Fprintf(w, "%2d. ", i+1)
778 w.Write(bytes.TrimRight(
779 bytes.ReplaceAll(buf.Bytes(), []byte("\n"), []byte("\n ")),
784 func (t *Torrent) haveInfo() bool {
788 // Returns a run-time generated MetaInfo that includes the info bytes and
789 // announce-list as currently known to the client.
790 func (t *Torrent) newMetaInfo() metainfo.MetaInfo {
791 return metainfo.MetaInfo{
792 CreationDate: time.Now().Unix(),
793 Comment: "dynamic metainfo from client",
794 CreatedBy: "go.torrent",
795 AnnounceList: t.metainfo.UpvertedAnnounceList().Clone(),
796 InfoBytes: func() []byte {
798 return t.metadataBytes
803 UrlList: func() []string {
804 ret := make([]string, 0, len(t.webSeeds))
805 for url := range t.webSeeds {
806 ret = append(ret, url)
814 func (t *Torrent) BytesMissing() (n int64) {
816 n = t.bytesMissingLocked()
821 func (t *Torrent) bytesMissingLocked() int64 {
825 func iterFlipped(b *roaring.Bitmap, end uint64, cb func(uint32) bool) {
826 roaring.Flip(b, 0, end).Iterate(cb)
829 func (t *Torrent) bytesLeft() (left int64) {
830 iterFlipped(&t._completedPieces, uint64(t.numPieces()), func(x uint32) bool {
831 p := t.piece(pieceIndex(x))
832 left += int64(p.length() - p.numDirtyBytes())
838 // Bytes left to give in tracker announces.
839 func (t *Torrent) bytesLeftAnnounce() int64 {
847 func (t *Torrent) piecePartiallyDownloaded(piece pieceIndex) bool {
848 if t.pieceComplete(piece) {
851 if t.pieceAllDirty(piece) {
854 return t.pieces[piece].hasDirtyChunks()
857 func (t *Torrent) usualPieceSize() int {
858 return int(t.info.PieceLength)
861 func (t *Torrent) numPieces() pieceIndex {
862 return t.info.NumPieces()
865 func (t *Torrent) numPiecesCompleted() (num pieceIndex) {
866 return pieceIndex(t._completedPieces.GetCardinality())
869 func (t *Torrent) close(wg *sync.WaitGroup) (err error) {
871 err = errors.New("already closed")
874 for _, f := range t.onClose {
877 if t.storage != nil {
882 defer t.storageLock.Unlock()
883 if f := t.storage.Close; f != nil {
886 t.logger.WithDefaultLevel(log.Warning).Printf("error closing storage: %v", err1)
891 t.iterPeers(func(p *Peer) {
894 if t.storage != nil {
895 t.deletePieceRequestOrder()
897 t.assertAllPiecesRelativeAvailabilityZero()
899 t.cl.event.Broadcast()
900 t.pieceStateChanges.Close()
901 t.updateWantPeersEvent()
905 func (t *Torrent) assertAllPiecesRelativeAvailabilityZero() {
906 for i := range t.pieces {
908 if p.relativeAvailability != 0 {
909 panic(fmt.Sprintf("piece %v has relative availability %v", i, p.relativeAvailability))
914 func (t *Torrent) requestOffset(r Request) int64 {
915 return torrentRequestOffset(t.length(), int64(t.usualPieceSize()), r)
918 // Return the request that would include the given offset into the torrent data. Returns !ok if
919 // there is no such request.
920 func (t *Torrent) offsetRequest(off int64) (req Request, ok bool) {
921 return torrentOffsetRequest(t.length(), t.info.PieceLength, int64(t.chunkSize), off)
924 func (t *Torrent) writeChunk(piece int, begin int64, data []byte) (err error) {
925 defer perf.ScopeTimerErr(&err)()
926 n, err := t.pieces[piece].Storage().WriteAt(data, begin)
927 if err == nil && n != len(data) {
928 err = io.ErrShortWrite
933 func (t *Torrent) bitfield() (bf []bool) {
934 bf = make([]bool, t.numPieces())
935 t._completedPieces.Iterate(func(piece uint32) (again bool) {
942 func (t *Torrent) pieceNumChunks(piece pieceIndex) chunkIndexType {
943 return chunkIndexType((t.pieceLength(piece) + t.chunkSize - 1) / t.chunkSize)
946 func (t *Torrent) chunksPerRegularPiece() chunkIndexType {
947 return t._chunksPerRegularPiece
950 func (t *Torrent) numChunks() RequestIndex {
951 if t.numPieces() == 0 {
954 return RequestIndex(t.numPieces()-1)*t.chunksPerRegularPiece() + t.pieceNumChunks(t.numPieces()-1)
957 func (t *Torrent) pendAllChunkSpecs(pieceIndex pieceIndex) {
958 t.dirtyChunks.RemoveRange(
959 uint64(t.pieceRequestIndexOffset(pieceIndex)),
960 uint64(t.pieceRequestIndexOffset(pieceIndex+1)))
963 func (t *Torrent) pieceLength(piece pieceIndex) pp.Integer {
964 if t.info.PieceLength == 0 {
965 // There will be no variance amongst pieces. Only pain.
968 if piece == t.numPieces()-1 {
969 ret := pp.Integer(t.length() % t.info.PieceLength)
974 return pp.Integer(t.info.PieceLength)
977 func (t *Torrent) smartBanBlockCheckingWriter(piece pieceIndex) *blockCheckingWriter {
978 return &blockCheckingWriter{
979 cache: &t.smartBanCache,
980 requestIndex: t.pieceRequestIndexOffset(piece),
981 chunkSize: t.chunkSize.Int(),
985 func (t *Torrent) hashPiece(piece pieceIndex) (
987 // These are peers that sent us blocks that differ from what we hash here.
988 differingPeers map[bannableAddr]struct{},
992 p.waitNoPendingWrites()
993 storagePiece := t.pieces[piece].Storage()
995 // Does the backend want to do its own hashing?
996 if i, ok := storagePiece.PieceImpl.(storage.SelfHashing); ok {
997 var sum metainfo.Hash
998 // log.Printf("A piece decided to self-hash: %d", piece)
999 sum, err = i.SelfHash()
1000 missinggo.CopyExact(&ret, sum)
1004 hash := pieceHash.New()
1005 const logPieceContents = false
1006 smartBanWriter := t.smartBanBlockCheckingWriter(piece)
1007 writers := []io.Writer{hash, smartBanWriter}
1008 var examineBuf bytes.Buffer
1009 if logPieceContents {
1010 writers = append(writers, &examineBuf)
1012 _, err = storagePiece.WriteTo(io.MultiWriter(writers...))
1013 if logPieceContents {
1014 t.logger.WithDefaultLevel(log.Debug).Printf("hashed %q with copy err %v", examineBuf.Bytes(), err)
1016 smartBanWriter.Flush()
1017 differingPeers = smartBanWriter.badPeers
1018 missinggo.CopyExact(&ret, hash.Sum(nil))
1022 func (t *Torrent) haveAnyPieces() bool {
1023 return !t._completedPieces.IsEmpty()
1026 func (t *Torrent) haveAllPieces() bool {
1030 return t._completedPieces.GetCardinality() == bitmap.BitRange(t.numPieces())
1033 func (t *Torrent) havePiece(index pieceIndex) bool {
1034 return t.haveInfo() && t.pieceComplete(index)
1037 func (t *Torrent) maybeDropMutuallyCompletePeer(
1038 // I'm not sure about taking peer here, not all peer implementations actually drop. Maybe that's
1042 if !t.cl.config.DropMutuallyCompletePeers {
1045 if !t.haveAllPieces() {
1048 if all, known := p.peerHasAllPieces(); !(known && all) {
1054 t.logger.WithDefaultLevel(log.Debug).Printf("dropping %v, which is mutually complete", p)
1058 func (t *Torrent) haveChunk(r Request) (ret bool) {
1060 // log.Println("have chunk", r, ret)
1065 if t.pieceComplete(pieceIndex(r.Index)) {
1068 p := &t.pieces[r.Index]
1069 return !p.pendingChunk(r.ChunkSpec, t.chunkSize)
1072 func chunkIndexFromChunkSpec(cs ChunkSpec, chunkSize pp.Integer) chunkIndexType {
1073 return chunkIndexType(cs.Begin / chunkSize)
1076 func (t *Torrent) wantPieceIndex(index pieceIndex) bool {
1077 return t._pendingPieces.Contains(uint32(index))
1080 // A pool of []*PeerConn, to reduce allocations in functions that need to index or sort Torrent
1081 // conns (which is a map).
1082 var peerConnSlices sync.Pool
1084 func getPeerConnSlice(cap int) []*PeerConn {
1085 getInterface := peerConnSlices.Get()
1086 if getInterface == nil {
1087 return make([]*PeerConn, 0, cap)
1089 return getInterface.([]*PeerConn)[:0]
1093 // Calls the given function with a slice of unclosed conns. It uses a pool to reduce allocations as
1094 // this is a frequent occurrence.
1095 func (t *Torrent) withUnclosedConns(f func([]*PeerConn)) {
1096 sl := t.appendUnclosedConns(getPeerConnSlice(len(t.conns)))
1098 peerConnSlices.Put(sl)
1101 func (t *Torrent) worstBadConnFromSlice(opts worseConnLensOpts, sl []*PeerConn) *PeerConn {
1102 wcs := worseConnSlice{conns: sl}
1105 for wcs.Len() != 0 {
1106 c := heap.Pop(&wcs).(*PeerConn)
1107 if opts.incomingIsBad && !c.outgoing {
1110 if opts.outgoingIsBad && c.outgoing {
1113 if c._stats.ChunksReadWasted.Int64() >= 6 && c._stats.ChunksReadWasted.Int64() > c._stats.ChunksReadUseful.Int64() {
1116 // If the connection is in the worst half of the established
1117 // connection quota and is older than a minute.
1118 if wcs.Len() >= (t.maxEstablishedConns+1)/2 {
1119 // Give connections 1 minute to prove themselves.
1120 if time.Since(c.completedHandshake) > time.Minute {
1128 // The worst connection is one that hasn't been sent, or sent anything useful for the longest. A bad
1129 // connection is one that usually sends us unwanted pieces, or has been in the worse half of the
1130 // established connections for more than a minute. This is O(n log n). If there was a way to not
1131 // consider the position of a conn relative to the total number, it could be reduced to O(n).
1132 func (t *Torrent) worstBadConn(opts worseConnLensOpts) (ret *PeerConn) {
1133 t.withUnclosedConns(func(ucs []*PeerConn) {
1134 ret = t.worstBadConnFromSlice(opts, ucs)
1139 type PieceStateChange struct {
1144 func (t *Torrent) publishPieceChange(piece pieceIndex) {
1145 t.cl._mu.Defer(func() {
1146 cur := t.pieceState(piece)
1147 p := &t.pieces[piece]
1148 if cur != p.publicPieceState {
1149 p.publicPieceState = cur
1150 t.pieceStateChanges.Publish(PieceStateChange{
1158 func (t *Torrent) pieceNumPendingChunks(piece pieceIndex) pp.Integer {
1159 if t.pieceComplete(piece) {
1162 return pp.Integer(t.pieceNumChunks(piece) - t.pieces[piece].numDirtyChunks())
1165 func (t *Torrent) pieceAllDirty(piece pieceIndex) bool {
1166 return t.pieces[piece].allChunksDirty()
1169 func (t *Torrent) readersChanged() {
1170 t.updateReaderPieces()
1171 t.updateAllPiecePriorities("Torrent.readersChanged")
1174 func (t *Torrent) updateReaderPieces() {
1175 t._readerNowPieces, t._readerReadaheadPieces = t.readerPiecePriorities()
1178 func (t *Torrent) readerPosChanged(from, to pieceRange) {
1182 t.updateReaderPieces()
1183 // Order the ranges, high and low.
1185 if l.begin > h.begin {
1188 if l.end < h.begin {
1189 // Two distinct ranges.
1190 t.updatePiecePriorities(l.begin, l.end, "Torrent.readerPosChanged")
1191 t.updatePiecePriorities(h.begin, h.end, "Torrent.readerPosChanged")
1198 t.updatePiecePriorities(l.begin, end, "Torrent.readerPosChanged")
1202 func (t *Torrent) maybeNewConns() {
1203 // Tickle the accept routine.
1204 t.cl.event.Broadcast()
1208 func (t *Torrent) piecePriorityChanged(piece pieceIndex, reason string) {
1209 if t._pendingPieces.Contains(uint32(piece)) {
1210 t.iterPeers(func(c *Peer) {
1211 // if c.requestState.Interested {
1214 if !c.isLowOnRequests() {
1217 if !c.peerHasPiece(piece) {
1220 if c.requestState.Interested && c.peerChoking && !c.peerAllowedFast.Contains(piece) {
1223 c.updateRequests(reason)
1227 t.publishPieceChange(piece)
1230 func (t *Torrent) updatePiecePriority(piece pieceIndex, reason string) {
1231 if !t.closed.IsSet() {
1232 // It would be possible to filter on pure-priority changes here to avoid churning the piece
1234 t.updatePieceRequestOrder(piece)
1236 p := &t.pieces[piece]
1237 newPrio := p.uncachedPriority()
1238 // t.logger.Printf("torrent %p: piece %d: uncached priority: %v", t, piece, newPrio)
1239 if newPrio == PiecePriorityNone {
1240 if !t._pendingPieces.CheckedRemove(uint32(piece)) {
1244 if !t._pendingPieces.CheckedAdd(uint32(piece)) {
1248 t.piecePriorityChanged(piece, reason)
1251 func (t *Torrent) updateAllPiecePriorities(reason string) {
1252 t.updatePiecePriorities(0, t.numPieces(), reason)
1255 // Update all piece priorities in one hit. This function should have the same
1256 // output as updatePiecePriority, but across all pieces.
1257 func (t *Torrent) updatePiecePriorities(begin, end pieceIndex, reason string) {
1258 for i := begin; i < end; i++ {
1259 t.updatePiecePriority(i, reason)
1263 // Returns the range of pieces [begin, end) that contains the extent of bytes.
1264 func (t *Torrent) byteRegionPieces(off, size int64) (begin, end pieceIndex) {
1265 if off >= t.length() {
1275 begin = pieceIndex(off / t.info.PieceLength)
1276 end = pieceIndex((off + size + t.info.PieceLength - 1) / t.info.PieceLength)
1277 if end > pieceIndex(t.info.NumPieces()) {
1278 end = pieceIndex(t.info.NumPieces())
1283 // Returns true if all iterations complete without breaking. Returns the read regions for all
1284 // readers. The reader regions should not be merged as some callers depend on this method to
1285 // enumerate readers.
1286 func (t *Torrent) forReaderOffsetPieces(f func(begin, end pieceIndex) (more bool)) (all bool) {
1287 for r := range t.readers {
1289 if p.begin >= p.end {
1292 if !f(p.begin, p.end) {
1299 func (t *Torrent) piecePriority(piece pieceIndex) piecePriority {
1300 return t.piece(piece).uncachedPriority()
1303 func (t *Torrent) pendRequest(req RequestIndex) {
1304 t.piece(t.pieceIndexOfRequestIndex(req)).pendChunkIndex(req % t.chunksPerRegularPiece())
1307 func (t *Torrent) pieceCompletionChanged(piece pieceIndex, reason string) {
1308 t.cl.event.Broadcast()
1309 if t.pieceComplete(piece) {
1310 t.onPieceCompleted(piece)
1312 t.onIncompletePiece(piece)
1314 t.updatePiecePriority(piece, reason)
1317 func (t *Torrent) numReceivedConns() (ret int) {
1318 for c := range t.conns {
1319 if c.Discovery == PeerSourceIncoming {
1326 func (t *Torrent) numOutgoingConns() (ret int) {
1327 for c := range t.conns {
1335 func (t *Torrent) maxHalfOpen() int {
1336 // Note that if we somehow exceed the maximum established conns, we want
1337 // the negative value to have an effect.
1338 establishedHeadroom := int64(t.maxEstablishedConns - len(t.conns))
1339 extraIncoming := int64(t.numReceivedConns() - t.maxEstablishedConns/2)
1340 // We want to allow some experimentation with new peers, and to try to
1341 // upset an oversupply of received connections.
1343 max(5, extraIncoming)+establishedHeadroom,
1344 int64(t.cl.config.HalfOpenConnsPerTorrent),
1348 func (t *Torrent) openNewConns() (initiated int) {
1349 defer t.updateWantPeersEvent()
1350 for t.peers.Len() != 0 {
1351 if !t.wantOutgoingConns() {
1354 if len(t.halfOpen) >= t.maxHalfOpen() {
1357 if len(t.cl.dialers) == 0 {
1360 if t.cl.numHalfOpen >= t.cl.config.TotalHalfOpenConns {
1363 p := t.peers.PopMax()
1370 func (t *Torrent) updatePieceCompletion(piece pieceIndex) bool {
1372 uncached := t.pieceCompleteUncached(piece)
1373 cached := p.completion()
1374 changed := cached != uncached
1375 complete := uncached.Complete
1376 p.storageCompletionOk = uncached.Ok
1379 t._completedPieces.Add(x)
1382 t._completedPieces.Remove(x)
1384 p.t.updatePieceRequestOrder(piece)
1386 if complete && len(p.dirtiers) != 0 {
1387 t.logger.Printf("marked piece %v complete but still has dirtiers", piece)
1390 log.Fstr("piece %d completion changed: %+v -> %+v", piece, cached, uncached).LogLevel(log.Debug, t.logger)
1391 t.pieceCompletionChanged(piece, "Torrent.updatePieceCompletion")
1396 // Non-blocking read. Client lock is not required.
1397 func (t *Torrent) readAt(b []byte, off int64) (n int, err error) {
1399 p := &t.pieces[off/t.info.PieceLength]
1400 p.waitNoPendingWrites()
1402 n1, err = p.Storage().ReadAt(b, off-p.Info().Offset())
1413 // Returns an error if the metadata was completed, but couldn't be set for some reason. Blame it on
1414 // the last peer to contribute. TODO: Actually we shouldn't blame peers for failure to open storage
1415 // etc. Also we should probably cached metadata pieces per-Peer, to isolate failure appropriately.
1416 func (t *Torrent) maybeCompleteMetadata() error {
1421 if !t.haveAllMetadataPieces() {
1422 // Don't have enough metadata pieces.
1425 err := t.setInfoBytesLocked(t.metadataBytes)
1427 t.invalidateMetadata()
1428 return fmt.Errorf("error setting info bytes: %s", err)
1430 if t.cl.config.Debug {
1431 t.logger.Printf("%s: got metadata from peers", t)
1436 func (t *Torrent) readerPiecePriorities() (now, readahead bitmap.Bitmap) {
1437 t.forReaderOffsetPieces(func(begin, end pieceIndex) bool {
1439 now.Add(bitmap.BitIndex(begin))
1440 readahead.AddRange(bitmap.BitRange(begin)+1, bitmap.BitRange(end))
1447 func (t *Torrent) needData() bool {
1448 if t.closed.IsSet() {
1454 return !t._pendingPieces.IsEmpty()
1457 func appendMissingStrings(old, new []string) (ret []string) {
1460 for _, n := range new {
1461 for _, o := range old {
1466 ret = append(ret, n)
1471 func appendMissingTrackerTiers(existing [][]string, minNumTiers int) (ret [][]string) {
1473 for minNumTiers > len(ret) {
1474 ret = append(ret, nil)
1479 func (t *Torrent) addTrackers(announceList [][]string) {
1480 fullAnnounceList := &t.metainfo.AnnounceList
1481 t.metainfo.AnnounceList = appendMissingTrackerTiers(*fullAnnounceList, len(announceList))
1482 for tierIndex, trackerURLs := range announceList {
1483 (*fullAnnounceList)[tierIndex] = appendMissingStrings((*fullAnnounceList)[tierIndex], trackerURLs)
1485 t.startMissingTrackerScrapers()
1486 t.updateWantPeersEvent()
1489 // Don't call this before the info is available.
1490 func (t *Torrent) bytesCompleted() int64 {
1494 return t.length() - t.bytesLeft()
1497 func (t *Torrent) SetInfoBytes(b []byte) (err error) {
1500 return t.setInfoBytesLocked(b)
1503 // Returns true if connection is removed from torrent.Conns.
1504 func (t *Torrent) deletePeerConn(c *PeerConn) (ret bool) {
1505 if !c.closed.IsSet() {
1506 panic("connection is not closed")
1507 // There are behaviours prevented by the closed state that will fail
1508 // if the connection has been deleted.
1512 // Avoid adding a drop event more than once. Probably we should track whether we've generated
1513 // the drop event against the PexConnState instead.
1515 if !t.cl.config.DisablePEX {
1519 torrent.Add("deleted connections", 1)
1520 c.deleteAllRequests("Torrent.deletePeerConn")
1521 t.assertPendingRequests()
1522 if t.numActivePeers() == 0 && len(t.connsWithAllPieces) != 0 {
1523 panic(t.connsWithAllPieces)
1528 func (t *Torrent) decPeerPieceAvailability(p *Peer) {
1529 if t.deleteConnWithAllPieces(p) {
1535 p.peerPieces().Iterate(func(i uint32) bool {
1536 p.t.decPieceAvailability(pieceIndex(i))
1541 func (t *Torrent) assertPendingRequests() {
1545 // var actual pendingRequests
1546 // if t.haveInfo() {
1547 // actual.m = make([]int, t.numChunks())
1549 // t.iterPeers(func(p *Peer) {
1550 // p.requestState.Requests.Iterate(func(x uint32) bool {
1555 // diff := cmp.Diff(actual.m, t.pendingRequests.m)
1561 func (t *Torrent) dropConnection(c *PeerConn) {
1562 t.cl.event.Broadcast()
1564 if t.deletePeerConn(c) {
1569 // Peers as in contact information for dialing out.
1570 func (t *Torrent) wantPeers() bool {
1571 if t.closed.IsSet() {
1574 if t.peers.Len() > t.cl.config.TorrentPeersLowWater {
1577 return t.wantOutgoingConns()
1580 func (t *Torrent) updateWantPeersEvent() {
1582 t.wantPeersEvent.Set()
1584 t.wantPeersEvent.Clear()
1588 // Returns whether the client should make effort to seed the torrent.
1589 func (t *Torrent) seeding() bool {
1591 if t.closed.IsSet() {
1594 if t.dataUploadDisallowed {
1597 if cl.config.NoUpload {
1600 if !cl.config.Seed {
1603 if cl.config.DisableAggressiveUpload && t.needData() {
1609 func (t *Torrent) onWebRtcConn(
1610 c datachannel.ReadWriteCloser,
1611 dcc webtorrent.DataChannelContext,
1614 netConn := webrtcNetConn{
1616 DataChannelContext: dcc,
1618 peerRemoteAddr := netConn.RemoteAddr()
1619 //t.logger.Levelf(log.Critical, "onWebRtcConn remote addr: %v", peerRemoteAddr)
1620 if t.cl.badPeerAddr(peerRemoteAddr) {
1623 localAddrIpPort := missinggo.IpPortFromNetAddr(netConn.LocalAddr())
1624 pc, err := t.cl.initiateProtocolHandshakes(
1625 context.Background(),
1630 outgoing: dcc.LocalOffered,
1631 remoteAddr: peerRemoteAddr,
1632 localPublicAddr: localAddrIpPort,
1633 network: webrtcNetwork,
1634 connString: fmt.Sprintf("webrtc offer_id %x: %v", dcc.OfferId, regularNetConnPeerConnConnString(netConn)),
1638 t.logger.WithDefaultLevel(log.Error).Printf("error in handshaking webrtc connection: %v", err)
1641 if dcc.LocalOffered {
1642 pc.Discovery = PeerSourceTracker
1644 pc.Discovery = PeerSourceIncoming
1646 pc.conn.SetWriteDeadline(time.Time{})
1649 err = t.cl.runHandshookConn(pc, t)
1651 t.logger.WithDefaultLevel(log.Debug).Printf("error running handshook webrtc conn: %v", err)
1655 func (t *Torrent) logRunHandshookConn(pc *PeerConn, logAll bool, level log.Level) {
1656 err := t.cl.runHandshookConn(pc, t)
1657 if err != nil || logAll {
1658 t.logger.WithDefaultLevel(level).Levelf(log.ErrorLevel(err), "error running handshook conn: %v", err)
1662 func (t *Torrent) runHandshookConnLoggingErr(pc *PeerConn) {
1663 t.logRunHandshookConn(pc, false, log.Debug)
1666 func (t *Torrent) startWebsocketAnnouncer(u url.URL) torrentTrackerAnnouncer {
1667 wtc, release := t.cl.websocketTrackers.Get(u.String(), t.infoHash)
1668 // This needs to run before the Torrent is dropped from the Client, to prevent a new webtorrent.TrackerClient for
1669 // the same info hash before the old one is cleaned up.
1670 t.onClose = append(t.onClose, release)
1671 wst := websocketTrackerStatus{u, wtc}
1673 err := wtc.Announce(tracker.Started, t.infoHash)
1675 t.logger.WithDefaultLevel(log.Warning).Printf(
1676 "error in initial announce to %q: %v",
1684 func (t *Torrent) startScrapingTracker(_url string) {
1688 u, err := url.Parse(_url)
1690 // URLs with a leading '*' appear to be a uTorrent convention to
1691 // disable trackers.
1693 log.Str("error parsing tracker url").AddValues("url", _url).Log(t.logger)
1697 if u.Scheme == "udp" {
1699 t.startScrapingTracker(u.String())
1701 t.startScrapingTracker(u.String())
1704 if _, ok := t.trackerAnnouncers[_url]; ok {
1707 sl := func() torrentTrackerAnnouncer {
1710 if t.cl.config.DisableWebtorrent {
1713 return t.startWebsocketAnnouncer(*u)
1715 if t.cl.config.DisableIPv4Peers || t.cl.config.DisableIPv4 {
1719 if t.cl.config.DisableIPv6 {
1723 newAnnouncer := &trackerScraper{
1726 lookupTrackerIp: t.cl.config.LookupTrackerIp,
1728 go newAnnouncer.Run()
1734 if t.trackerAnnouncers == nil {
1735 t.trackerAnnouncers = make(map[string]torrentTrackerAnnouncer)
1737 t.trackerAnnouncers[_url] = sl
1740 // Adds and starts tracker scrapers for tracker URLs that aren't already
1742 func (t *Torrent) startMissingTrackerScrapers() {
1743 if t.cl.config.DisableTrackers {
1746 t.startScrapingTracker(t.metainfo.Announce)
1747 for _, tier := range t.metainfo.AnnounceList {
1748 for _, url := range tier {
1749 t.startScrapingTracker(url)
1754 // Returns an AnnounceRequest with fields filled out to defaults and current
1756 func (t *Torrent) announceRequest(event tracker.AnnounceEvent) tracker.AnnounceRequest {
1757 // Note that IPAddress is not set. It's set for UDP inside the tracker code, since it's
1758 // dependent on the network in use.
1759 return tracker.AnnounceRequest{
1761 NumWant: func() int32 {
1762 if t.wantPeers() && len(t.cl.dialers) > 0 {
1763 return 200 // Win has UDP packet limit. See: https://github.com/anacrolix/torrent/issues/764
1768 Port: uint16(t.cl.incomingPeerPort()),
1769 PeerId: t.cl.peerID,
1770 InfoHash: t.infoHash,
1771 Key: t.cl.announceKey(),
1773 // The following are vaguely described in BEP 3.
1775 Left: t.bytesLeftAnnounce(),
1776 Uploaded: t.stats.BytesWrittenData.Int64(),
1777 // There's no mention of wasted or unwanted download in the BEP.
1778 Downloaded: t.stats.BytesReadUsefulData.Int64(),
1782 // Adds peers revealed in an announce until the announce ends, or we have
1784 func (t *Torrent) consumeDhtAnnouncePeers(pvs <-chan dht.PeersValues) {
1786 for v := range pvs {
1789 for _, cp := range v.Peers {
1791 // Can't do anything with this.
1794 if t.addPeer(PeerInfo{
1795 Addr: ipPortAddr{cp.IP, cp.Port},
1796 Source: PeerSourceDhtGetPeers,
1803 // log.Printf("added %v peers from dht for %v", added, t.InfoHash().HexString())
1808 // Announce using the provided DHT server. Peers are consumed automatically. done is closed when the
1809 // announce ends. stop will force the announce to end.
1810 func (t *Torrent) AnnounceToDht(s DhtServer) (done <-chan struct{}, stop func(), err error) {
1811 ps, err := s.Announce(t.infoHash, t.cl.incomingPeerPort(), true)
1815 _done := make(chan struct{})
1819 t.consumeDhtAnnouncePeers(ps.Peers())
1825 func (t *Torrent) timeboxedAnnounceToDht(s DhtServer) error {
1826 _, stop, err := t.AnnounceToDht(s)
1831 case <-t.closed.Done():
1832 case <-time.After(5 * time.Minute):
1838 func (t *Torrent) dhtAnnouncer(s DhtServer) {
1844 if t.closed.IsSet() {
1847 // We're also announcing ourselves as a listener, so we don't just want peer addresses.
1848 // TODO: We can include the announce_peer step depending on whether we can receive
1849 // inbound connections. We should probably only announce once every 15 mins too.
1850 if !t.wantAnyConns() {
1853 // TODO: Determine if there's a listener on the port we're announcing.
1854 if len(cl.dialers) == 0 && len(cl.listeners) == 0 {
1865 err := t.timeboxedAnnounceToDht(s)
1867 t.logger.WithDefaultLevel(log.Warning).Printf("error announcing %q to DHT: %s", t, err)
1873 func (t *Torrent) addPeers(peers []PeerInfo) (added int) {
1874 for _, p := range peers {
1882 // The returned TorrentStats may require alignment in memory. See
1883 // https://github.com/anacrolix/torrent/issues/383.
1884 func (t *Torrent) Stats() TorrentStats {
1886 defer t.cl.rUnlock()
1887 return t.statsLocked()
1890 func (t *Torrent) statsLocked() (ret TorrentStats) {
1891 ret.ActivePeers = len(t.conns)
1892 ret.HalfOpenPeers = len(t.halfOpen)
1893 ret.PendingPeers = t.peers.Len()
1894 ret.TotalPeers = t.numTotalPeers()
1895 ret.ConnectedSeeders = 0
1896 for c := range t.conns {
1897 if all, ok := c.peerHasAllPieces(); all && ok {
1898 ret.ConnectedSeeders++
1901 ret.ConnStats = t.stats.Copy()
1902 ret.PiecesComplete = t.numPiecesCompleted()
1906 // The total number of peers in the torrent.
1907 func (t *Torrent) numTotalPeers() int {
1908 peers := make(map[string]struct{})
1909 for conn := range t.conns {
1910 ra := conn.conn.RemoteAddr()
1912 // It's been closed and doesn't support RemoteAddr.
1915 peers[ra.String()] = struct{}{}
1917 for addr := range t.halfOpen {
1918 peers[addr] = struct{}{}
1920 t.peers.Each(func(peer PeerInfo) {
1921 peers[peer.Addr.String()] = struct{}{}
1926 // Reconcile bytes transferred before connection was associated with a
1928 func (t *Torrent) reconcileHandshakeStats(c *PeerConn) {
1929 if c._stats != (ConnStats{
1930 // Handshakes should only increment these fields:
1931 BytesWritten: c._stats.BytesWritten,
1932 BytesRead: c._stats.BytesRead,
1936 c.postHandshakeStats(func(cs *ConnStats) {
1937 cs.BytesRead.Add(c._stats.BytesRead.Int64())
1938 cs.BytesWritten.Add(c._stats.BytesWritten.Int64())
1940 c.reconciledHandshakeStats = true
1943 // Returns true if the connection is added.
1944 func (t *Torrent) addPeerConn(c *PeerConn) (err error) {
1947 torrent.Add("added connections", 1)
1950 if t.closed.IsSet() {
1951 return errors.New("torrent closed")
1953 for c0 := range t.conns {
1954 if c.PeerID != c0.PeerID {
1957 if !t.cl.config.DropDuplicatePeerIds {
1960 if c.hasPreferredNetworkOver(c0) {
1962 t.deletePeerConn(c0)
1964 return errors.New("existing connection preferred")
1967 if len(t.conns) >= t.maxEstablishedConns {
1968 numOutgoing := t.numOutgoingConns()
1969 numIncoming := len(t.conns) - numOutgoing
1970 c := t.worstBadConn(worseConnLensOpts{
1971 // We've already established that we have too many connections at this point, so we just
1972 // need to match what kind we have too many of vs. what we're trying to add now.
1973 incomingIsBad: (numIncoming-numOutgoing > 1) && c.outgoing,
1974 outgoingIsBad: (numOutgoing-numIncoming > 1) && !c.outgoing,
1977 return errors.New("don't want conn")
1982 if len(t.conns) >= t.maxEstablishedConns {
1985 t.conns[c] = struct{}{}
1986 t.cl.event.Broadcast()
1987 if !t.cl.config.DisablePEX && !c.PeerExtensionBytes.SupportsExtended() {
1988 t.pex.Add(c) // as no further extended handshake expected
1993 func (t *Torrent) newConnsAllowed() bool {
1994 if !t.networkingEnabled.Bool() {
1997 if t.closed.IsSet() {
2000 if !t.needData() && (!t.seeding() || !t.haveAnyPieces()) {
2006 func (t *Torrent) wantAnyConns() bool {
2007 if !t.networkingEnabled.Bool() {
2010 if t.closed.IsSet() {
2013 if !t.needData() && (!t.seeding() || !t.haveAnyPieces()) {
2016 return len(t.conns) < t.maxEstablishedConns
2019 func (t *Torrent) wantOutgoingConns() bool {
2020 if !t.newConnsAllowed() {
2023 if len(t.conns) < t.maxEstablishedConns {
2026 numIncomingConns := len(t.conns) - t.numOutgoingConns()
2027 return t.worstBadConn(worseConnLensOpts{
2028 incomingIsBad: numIncomingConns-t.numOutgoingConns() > 1,
2029 outgoingIsBad: false,
2033 func (t *Torrent) wantIncomingConns() bool {
2034 if !t.newConnsAllowed() {
2037 if len(t.conns) < t.maxEstablishedConns {
2040 numIncomingConns := len(t.conns) - t.numOutgoingConns()
2041 return t.worstBadConn(worseConnLensOpts{
2042 incomingIsBad: false,
2043 outgoingIsBad: t.numOutgoingConns()-numIncomingConns > 1,
2047 func (t *Torrent) SetMaxEstablishedConns(max int) (oldMax int) {
2050 oldMax = t.maxEstablishedConns
2051 t.maxEstablishedConns = max
2052 wcs := worseConnSlice{
2053 conns: t.appendConns(nil, func(*PeerConn) bool {
2057 wcs.initKeys(worseConnLensOpts{})
2059 for len(t.conns) > t.maxEstablishedConns && wcs.Len() > 0 {
2060 t.dropConnection(heap.Pop(&wcs).(*PeerConn))
2066 func (t *Torrent) pieceHashed(piece pieceIndex, passed bool, hashIoErr error) {
2067 t.logger.LazyLog(log.Debug, func() log.Msg {
2068 return log.Fstr("hashed piece %d (passed=%t)", piece, passed)
2072 t.cl.event.Broadcast()
2073 if t.closed.IsSet() {
2077 // Don't score the first time a piece is hashed, it could be an initial check.
2078 if p.storageCompletionOk {
2080 pieceHashedCorrect.Add(1)
2083 "piece %d failed hash: %d connections contributed", piece, len(p.dirtiers),
2084 ).AddValues(t, p).LogLevel(
2086 log.Debug, t.logger)
2088 pieceHashedNotCorrect.Add(1)
2093 t.publishPieceChange(piece)
2096 t.publishPieceChange(piece)
2100 if len(p.dirtiers) != 0 {
2101 // Don't increment stats above connection-level for every involved connection.
2102 t.allStats((*ConnStats).incrementPiecesDirtiedGood)
2104 for c := range p.dirtiers {
2105 c._stats.incrementPiecesDirtiedGood()
2107 t.clearPieceTouchers(piece)
2108 hasDirty := p.hasDirtyChunks()
2111 p.Flush() // You can be synchronous here!
2113 err := p.Storage().MarkComplete()
2115 t.logger.Printf("%T: error marking piece complete %d: %s", t.storage, piece, err)
2119 if t.closed.IsSet() {
2122 t.pendAllChunkSpecs(piece)
2124 if len(p.dirtiers) != 0 && p.allChunksDirty() && hashIoErr == nil {
2125 // Peers contributed to all the data for this piece hash failure, and the failure was
2126 // not due to errors in the storage (such as data being dropped in a cache).
2128 // Increment Torrent and above stats, and then specific connections.
2129 t.allStats((*ConnStats).incrementPiecesDirtiedBad)
2130 for c := range p.dirtiers {
2131 // Y u do dis peer?!
2132 c.stats().incrementPiecesDirtiedBad()
2135 bannableTouchers := make([]*Peer, 0, len(p.dirtiers))
2136 for c := range p.dirtiers {
2138 bannableTouchers = append(bannableTouchers, c)
2141 t.clearPieceTouchers(piece)
2142 slices.Sort(bannableTouchers, connLessTrusted)
2144 if t.cl.config.Debug {
2146 "bannable conns by trust for piece %d: %v",
2148 func() (ret []connectionTrust) {
2149 for _, c := range bannableTouchers {
2150 ret = append(ret, c.trust())
2157 if len(bannableTouchers) >= 1 {
2158 c := bannableTouchers[0]
2159 if len(bannableTouchers) != 1 {
2160 t.logger.Levelf(log.Warning, "would have banned %v for touching piece %v after failed piece check", c.remoteIp(), piece)
2162 // Turns out it's still useful to ban peers like this because if there's only a
2163 // single peer for a piece, and we never progress that piece to completion, we
2164 // will never smart-ban them. Discovered in
2165 // https://github.com/anacrolix/torrent/issues/715.
2166 t.logger.Levelf(log.Warning, "banning %v for being sole dirtier of piece %v after failed piece check", c, piece)
2171 t.onIncompletePiece(piece)
2172 p.Storage().MarkNotComplete()
2174 t.updatePieceCompletion(piece)
2177 func (t *Torrent) cancelRequestsForPiece(piece pieceIndex) {
2178 start := t.pieceRequestIndexOffset(piece)
2179 end := start + t.pieceNumChunks(piece)
2180 for ri := start; ri < end; ri++ {
2185 func (t *Torrent) onPieceCompleted(piece pieceIndex) {
2186 t.pendAllChunkSpecs(piece)
2187 t.cancelRequestsForPiece(piece)
2188 t.piece(piece).readerCond.Broadcast()
2189 for conn := range t.conns {
2191 t.maybeDropMutuallyCompletePeer(&conn.Peer)
2195 // Called when a piece is found to be not complete.
2196 func (t *Torrent) onIncompletePiece(piece pieceIndex) {
2197 if t.pieceAllDirty(piece) {
2198 t.pendAllChunkSpecs(piece)
2200 if !t.wantPieceIndex(piece) {
2201 // t.logger.Printf("piece %d incomplete and unwanted", piece)
2204 // We could drop any connections that we told we have a piece that we
2205 // don't here. But there's a test failure, and it seems clients don't care
2206 // if you request pieces that you already claim to have. Pruning bad
2207 // connections might just remove any connections that aren't treating us
2208 // favourably anyway.
2210 // for c := range t.conns {
2211 // if c.sentHave(piece) {
2215 t.iterPeers(func(conn *Peer) {
2216 if conn.peerHasPiece(piece) {
2217 conn.updateRequests("piece incomplete")
2222 func (t *Torrent) tryCreateMorePieceHashers() {
2223 for !t.closed.IsSet() && t.activePieceHashes < 2 && t.tryCreatePieceHasher() {
2227 func (t *Torrent) tryCreatePieceHasher() bool {
2228 if t.storage == nil {
2231 pi, ok := t.getPieceToHash()
2236 t.piecesQueuedForHash.Remove(bitmap.BitIndex(pi))
2238 t.publishPieceChange(pi)
2239 t.updatePiecePriority(pi, "Torrent.tryCreatePieceHasher")
2240 t.storageLock.RLock()
2241 t.activePieceHashes++
2242 go t.pieceHasher(pi)
2246 func (t *Torrent) getPieceToHash() (ret pieceIndex, ok bool) {
2247 t.piecesQueuedForHash.IterTyped(func(i pieceIndex) bool {
2248 if t.piece(i).hashing {
2258 func (t *Torrent) dropBannedPeers() {
2259 t.iterPeers(func(p *Peer) {
2260 remoteIp := p.remoteIp()
2261 if remoteIp == nil {
2262 if p.bannableAddr.Ok {
2263 t.logger.WithDefaultLevel(log.Debug).Printf("can't get remote ip for peer %v", p)
2267 netipAddr := netip.MustParseAddr(remoteIp.String())
2268 if Some(netipAddr) != p.bannableAddr {
2269 t.logger.WithDefaultLevel(log.Debug).Printf(
2270 "peer remote ip does not match its bannable addr [peer=%v, remote ip=%v, bannable addr=%v]",
2271 p, remoteIp, p.bannableAddr)
2273 if _, ok := t.cl.badPeerIPs[netipAddr]; ok {
2274 // Should this be a close?
2276 t.logger.WithDefaultLevel(log.Debug).Printf("dropped %v for banned remote IP %v", p, netipAddr)
2281 func (t *Torrent) pieceHasher(index pieceIndex) {
2283 sum, failedPeers, copyErr := t.hashPiece(index)
2284 correct := sum == *p.hash
2288 log.Fmsg("piece %v (%s) hash failure copy error: %v", p, p.hash.HexString(), copyErr).Log(t.logger)
2290 t.storageLock.RUnlock()
2294 for peer := range failedPeers {
2295 t.cl.banPeerIP(peer.AsSlice())
2296 t.logger.WithDefaultLevel(log.Debug).Printf("smart banned %v for piece %v", peer, index)
2299 for ri := t.pieceRequestIndexOffset(index); ri < t.pieceRequestIndexOffset(index+1); ri++ {
2300 t.smartBanCache.ForgetBlock(ri)
2304 t.pieceHashed(index, correct, copyErr)
2305 t.updatePiecePriority(index, "Torrent.pieceHasher")
2306 t.activePieceHashes--
2307 t.tryCreateMorePieceHashers()
2310 // Return the connections that touched a piece, and clear the entries while doing it.
2311 func (t *Torrent) clearPieceTouchers(pi pieceIndex) {
2313 for c := range p.dirtiers {
2314 delete(c.peerTouchedPieces, pi)
2315 delete(p.dirtiers, c)
2319 func (t *Torrent) peersAsSlice() (ret []*Peer) {
2320 t.iterPeers(func(p *Peer) {
2321 ret = append(ret, p)
2326 func (t *Torrent) queuePieceCheck(pieceIndex pieceIndex) {
2327 piece := t.piece(pieceIndex)
2328 if piece.queuedForHash() {
2331 t.piecesQueuedForHash.Add(bitmap.BitIndex(pieceIndex))
2332 t.publishPieceChange(pieceIndex)
2333 t.updatePiecePriority(pieceIndex, "Torrent.queuePieceCheck")
2334 t.tryCreateMorePieceHashers()
2337 // Forces all the pieces to be re-hashed. See also Piece.VerifyData. This should not be called
2338 // before the Info is available.
2339 func (t *Torrent) VerifyData() {
2340 for i := pieceIndex(0); i < t.NumPieces(); i++ {
2341 t.Piece(i).VerifyData()
2345 // Start the process of connecting to the given peer for the given torrent if appropriate.
2346 func (t *Torrent) initiateConn(peer PeerInfo) {
2347 if peer.Id == t.cl.peerID {
2350 if t.cl.badPeerAddr(peer.Addr) && !peer.Trusted {
2354 if t.addrActive(addr.String()) {
2358 t.halfOpen[addr.String()] = peer
2359 go t.cl.outgoingConnection(t, addr, peer.Source, peer.Trusted)
2362 // Adds a trusted, pending peer for each of the given Client's addresses. Typically used in tests to
2363 // quickly make one Client visible to the Torrent of another Client.
2364 func (t *Torrent) AddClientPeer(cl *Client) int {
2365 return t.AddPeers(func() (ps []PeerInfo) {
2366 for _, la := range cl.ListenAddrs() {
2367 ps = append(ps, PeerInfo{
2376 // All stats that include this Torrent. Useful when we want to increment ConnStats but not for every
2378 func (t *Torrent) allStats(f func(*ConnStats)) {
2383 func (t *Torrent) hashingPiece(i pieceIndex) bool {
2384 return t.pieces[i].hashing
2387 func (t *Torrent) pieceQueuedForHash(i pieceIndex) bool {
2388 return t.piecesQueuedForHash.Get(bitmap.BitIndex(i))
2391 func (t *Torrent) dialTimeout() time.Duration {
2392 return reducedDialTimeout(t.cl.config.MinDialTimeout, t.cl.config.NominalDialTimeout, t.cl.config.HalfOpenConnsPerTorrent, t.peers.Len())
2395 func (t *Torrent) piece(i int) *Piece {
2399 func (t *Torrent) onWriteChunkErr(err error) {
2400 if t.userOnWriteChunkErr != nil {
2401 go t.userOnWriteChunkErr(err)
2404 t.logger.WithDefaultLevel(log.Critical).Printf("default chunk write error handler: disabling data download")
2405 t.disallowDataDownloadLocked()
2408 func (t *Torrent) DisallowDataDownload() {
2409 t.disallowDataDownloadLocked()
2412 func (t *Torrent) disallowDataDownloadLocked() {
2413 t.dataDownloadDisallowed.Set()
2416 func (t *Torrent) AllowDataDownload() {
2417 t.dataDownloadDisallowed.Clear()
2420 // Enables uploading data, if it was disabled.
2421 func (t *Torrent) AllowDataUpload() {
2424 t.dataUploadDisallowed = false
2425 for c := range t.conns {
2426 c.updateRequests("allow data upload")
2430 // Disables uploading data, if it was enabled.
2431 func (t *Torrent) DisallowDataUpload() {
2434 t.dataUploadDisallowed = true
2435 for c := range t.conns {
2436 // TODO: This doesn't look right. Shouldn't we tickle writers to choke peers or something instead?
2437 c.updateRequests("disallow data upload")
2441 // Sets a handler that is called if there's an error writing a chunk to local storage. By default,
2442 // or if nil, a critical message is logged, and data download is disabled.
2443 func (t *Torrent) SetOnWriteChunkError(f func(error)) {
2446 t.userOnWriteChunkErr = f
2449 func (t *Torrent) iterPeers(f func(p *Peer)) {
2450 for pc := range t.conns {
2453 for _, ws := range t.webSeeds {
2458 func (t *Torrent) callbacks() *Callbacks {
2459 return &t.cl.config.Callbacks
2462 type AddWebSeedsOpt func(*webseed.Client)
2464 // Sets the WebSeed trailing path escaper for a webseed.Client.
2465 func WebSeedPathEscaper(custom webseed.PathEscaper) AddWebSeedsOpt {
2466 return func(c *webseed.Client) {
2467 c.PathEscaper = custom
2471 func (t *Torrent) AddWebSeeds(urls []string, opts ...AddWebSeedsOpt) {
2474 for _, u := range urls {
2475 t.addWebSeed(u, opts...)
2479 func (t *Torrent) addWebSeed(url string, opts ...AddWebSeedsOpt) {
2480 if t.cl.config.DisableWebseeds {
2483 if _, ok := t.webSeeds[url]; ok {
2486 // I don't think Go http supports pipelining requests. However, we can have more ready to go
2487 // right away. This value should be some multiple of the number of connections to a host. I
2488 // would expect that double maxRequests plus a bit would be appropriate. This value is based on
2489 // downloading Sintel (08ada5a7a6183aae1e09d831df6748d566095a10) from
2490 // "https://webtorrent.io/torrents/".
2491 const maxRequests = 16
2497 reconciledHandshakeStats: true,
2498 // This should affect how often we have to recompute requests for this peer. Note that
2499 // because we can request more than 1 thing at a time over HTTP, we will hit the low
2500 // requests mark more often, so recomputation is probably sooner than with regular peer
2501 // conns. ~4x maxRequests would be about right.
2502 PeerMaxRequests: 128,
2503 // TODO: Set ban prefix?
2504 RemoteAddr: remoteAddrFromUrl(url),
2505 callbacks: t.callbacks(),
2507 client: webseed.Client{
2508 HttpClient: t.cl.httpClient,
2510 ResponseBodyWrapper: func(r io.Reader) io.Reader {
2511 return &rateLimitedReader{
2512 l: t.cl.config.DownloadRateLimiter,
2517 activeRequests: make(map[Request]webseed.Request, maxRequests),
2519 ws.peer.initRequestState()
2520 for _, opt := range opts {
2523 ws.peer.initUpdateRequestsTimer()
2524 ws.requesterCond.L = t.cl.locker()
2525 for i := 0; i < maxRequests; i += 1 {
2528 for _, f := range t.callbacks().NewPeer {
2531 ws.peer.logger = t.logger.WithContextValue(&ws)
2532 ws.peer.peerImpl = &ws
2534 ws.onGotInfo(t.info)
2536 t.webSeeds[url] = &ws.peer
2539 func (t *Torrent) peerIsActive(p *Peer) (active bool) {
2540 t.iterPeers(func(p1 *Peer) {
2548 func (t *Torrent) requestIndexToRequest(ri RequestIndex) Request {
2549 index := t.pieceIndexOfRequestIndex(ri)
2552 t.piece(index).chunkIndexSpec(ri % t.chunksPerRegularPiece()),
2556 func (t *Torrent) requestIndexFromRequest(r Request) RequestIndex {
2557 return t.pieceRequestIndexOffset(pieceIndex(r.Index)) + RequestIndex(r.Begin/t.chunkSize)
2560 func (t *Torrent) pieceRequestIndexOffset(piece pieceIndex) RequestIndex {
2561 return RequestIndex(piece) * t.chunksPerRegularPiece()
2564 func (t *Torrent) updateComplete() {
2565 t.Complete.SetBool(t.haveAllPieces())
2568 func (t *Torrent) cancelRequest(r RequestIndex) *Peer {
2569 p := t.requestingPeer(r)
2573 // TODO: This is a check that an old invariant holds. It can be removed after some testing.
2574 //delete(t.pendingRequests, r)
2575 if _, ok := t.requestState[r]; ok {
2576 panic("expected request state to be gone")
2581 func (t *Torrent) requestingPeer(r RequestIndex) *Peer {
2582 return t.requestState[r].peer
2585 func (t *Torrent) addConnWithAllPieces(p *Peer) {
2586 if t.connsWithAllPieces == nil {
2587 t.connsWithAllPieces = make(map[*Peer]struct{}, t.maxEstablishedConns)
2589 t.connsWithAllPieces[p] = struct{}{}
2592 func (t *Torrent) deleteConnWithAllPieces(p *Peer) bool {
2593 _, ok := t.connsWithAllPieces[p]
2594 delete(t.connsWithAllPieces, p)
2598 func (t *Torrent) numActivePeers() int {
2599 return len(t.conns) + len(t.webSeeds)
2602 func (t *Torrent) hasStorageCap() bool {
2603 f := t.storage.Capacity
2611 func (t *Torrent) pieceIndexOfRequestIndex(ri RequestIndex) pieceIndex {
2612 return pieceIndex(ri / t.chunksPerRegularPiece())
2615 func (t *Torrent) iterUndirtiedRequestIndexesInPiece(
2616 reuseIter *typedRoaring.Iterator[RequestIndex],
2618 f func(RequestIndex),
2620 reuseIter.Initialize(&t.dirtyChunks)
2621 pieceRequestIndexOffset := t.pieceRequestIndexOffset(piece)
2622 iterBitmapUnsetInRange(
2624 pieceRequestIndexOffset, pieceRequestIndexOffset+t.pieceNumChunks(piece),
2629 type requestState struct {
2634 // Returns an error if a received chunk is out of bounds in someway.
2635 func (t *Torrent) checkValidReceiveChunk(r Request) error {
2637 return errors.New("torrent missing info")
2639 if int(r.Index) >= t.numPieces() {
2640 return fmt.Errorf("chunk index %v, torrent num pieces %v", r.Index, t.numPieces())
2642 pieceLength := t.pieceLength(pieceIndex(r.Index))
2643 if r.Begin >= pieceLength {
2644 return fmt.Errorf("chunk begins beyond end of piece (%v >= %v)", r.Begin, pieceLength)
2646 // We could check chunk lengths here, but chunk request size is not changed often, and tricky
2647 // for peers to manipulate as they need to send potentially large buffers to begin with. There
2648 // should be considerable checks elsewhere for this case due to the network overhead. We should
2649 // catch most of the overflow manipulation stuff by checking index and begin above.