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 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 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)
773 for i, c := range peers {
774 fmt.Fprintf(w, "%2d. ", i+1)
779 func (t *Torrent) haveInfo() bool {
783 // Returns a run-time generated MetaInfo that includes the info bytes and
784 // announce-list as currently known to the client.
785 func (t *Torrent) newMetaInfo() metainfo.MetaInfo {
786 return metainfo.MetaInfo{
787 CreationDate: time.Now().Unix(),
788 Comment: "dynamic metainfo from client",
789 CreatedBy: "go.torrent",
790 AnnounceList: t.metainfo.UpvertedAnnounceList().Clone(),
791 InfoBytes: func() []byte {
793 return t.metadataBytes
798 UrlList: func() []string {
799 ret := make([]string, 0, len(t.webSeeds))
800 for url := range t.webSeeds {
801 ret = append(ret, url)
809 func (t *Torrent) BytesMissing() (n int64) {
811 n = t.bytesMissingLocked()
816 func (t *Torrent) bytesMissingLocked() int64 {
820 func iterFlipped(b *roaring.Bitmap, end uint64, cb func(uint32) bool) {
821 roaring.Flip(b, 0, end).Iterate(cb)
824 func (t *Torrent) bytesLeft() (left int64) {
825 iterFlipped(&t._completedPieces, uint64(t.numPieces()), func(x uint32) bool {
826 p := t.piece(pieceIndex(x))
827 left += int64(p.length() - p.numDirtyBytes())
833 // Bytes left to give in tracker announces.
834 func (t *Torrent) bytesLeftAnnounce() int64 {
842 func (t *Torrent) piecePartiallyDownloaded(piece pieceIndex) bool {
843 if t.pieceComplete(piece) {
846 if t.pieceAllDirty(piece) {
849 return t.pieces[piece].hasDirtyChunks()
852 func (t *Torrent) usualPieceSize() int {
853 return int(t.info.PieceLength)
856 func (t *Torrent) numPieces() pieceIndex {
857 return t.info.NumPieces()
860 func (t *Torrent) numPiecesCompleted() (num pieceIndex) {
861 return pieceIndex(t._completedPieces.GetCardinality())
864 func (t *Torrent) close(wg *sync.WaitGroup) (err error) {
866 err = errors.New("already closed")
869 for _, f := range t.onClose {
872 if t.storage != nil {
877 defer t.storageLock.Unlock()
878 if f := t.storage.Close; f != nil {
881 t.logger.WithDefaultLevel(log.Warning).Printf("error closing storage: %v", err1)
886 t.iterPeers(func(p *Peer) {
889 if t.storage != nil {
890 t.deletePieceRequestOrder()
892 for i := range t.pieces {
894 if p.relativeAvailability != 0 {
895 panic(fmt.Sprintf("piece %v has relative availability %v", i, p.relativeAvailability))
899 t.cl.event.Broadcast()
900 t.pieceStateChanges.Close()
901 t.updateWantPeersEvent()
905 func (t *Torrent) requestOffset(r Request) int64 {
906 return torrentRequestOffset(t.length(), int64(t.usualPieceSize()), r)
909 // Return the request that would include the given offset into the torrent data. Returns !ok if
910 // there is no such request.
911 func (t *Torrent) offsetRequest(off int64) (req Request, ok bool) {
912 return torrentOffsetRequest(t.length(), t.info.PieceLength, int64(t.chunkSize), off)
915 func (t *Torrent) writeChunk(piece int, begin int64, data []byte) (err error) {
916 defer perf.ScopeTimerErr(&err)()
917 n, err := t.pieces[piece].Storage().WriteAt(data, begin)
918 if err == nil && n != len(data) {
919 err = io.ErrShortWrite
924 func (t *Torrent) bitfield() (bf []bool) {
925 bf = make([]bool, t.numPieces())
926 t._completedPieces.Iterate(func(piece uint32) (again bool) {
933 func (t *Torrent) pieceNumChunks(piece pieceIndex) chunkIndexType {
934 return chunkIndexType((t.pieceLength(piece) + t.chunkSize - 1) / t.chunkSize)
937 func (t *Torrent) chunksPerRegularPiece() chunkIndexType {
938 return t._chunksPerRegularPiece
941 func (t *Torrent) numChunks() RequestIndex {
942 if t.numPieces() == 0 {
945 return RequestIndex(t.numPieces()-1)*t.chunksPerRegularPiece() + t.pieceNumChunks(t.numPieces()-1)
948 func (t *Torrent) pendAllChunkSpecs(pieceIndex pieceIndex) {
949 t.dirtyChunks.RemoveRange(
950 uint64(t.pieceRequestIndexOffset(pieceIndex)),
951 uint64(t.pieceRequestIndexOffset(pieceIndex+1)))
954 func (t *Torrent) pieceLength(piece pieceIndex) pp.Integer {
955 if t.info.PieceLength == 0 {
956 // There will be no variance amongst pieces. Only pain.
959 if piece == t.numPieces()-1 {
960 ret := pp.Integer(t.length() % t.info.PieceLength)
965 return pp.Integer(t.info.PieceLength)
968 func (t *Torrent) smartBanBlockCheckingWriter(piece pieceIndex) *blockCheckingWriter {
969 return &blockCheckingWriter{
970 cache: &t.smartBanCache,
971 requestIndex: t.pieceRequestIndexOffset(piece),
972 chunkSize: t.chunkSize.Int(),
976 func (t *Torrent) hashPiece(piece pieceIndex) (
978 // These are peers that sent us blocks that differ from what we hash here.
979 differingPeers map[bannableAddr]struct{},
983 p.waitNoPendingWrites()
984 storagePiece := t.pieces[piece].Storage()
986 // Does the backend want to do its own hashing?
987 if i, ok := storagePiece.PieceImpl.(storage.SelfHashing); ok {
988 var sum metainfo.Hash
989 // log.Printf("A piece decided to self-hash: %d", piece)
990 sum, err = i.SelfHash()
991 missinggo.CopyExact(&ret, sum)
995 hash := pieceHash.New()
996 const logPieceContents = false
997 smartBanWriter := t.smartBanBlockCheckingWriter(piece)
998 writers := []io.Writer{hash, smartBanWriter}
999 var examineBuf bytes.Buffer
1000 if logPieceContents {
1001 writers = append(writers, &examineBuf)
1003 _, err = storagePiece.WriteTo(io.MultiWriter(writers...))
1004 if logPieceContents {
1005 t.logger.WithDefaultLevel(log.Debug).Printf("hashed %q with copy err %v", examineBuf.Bytes(), err)
1007 smartBanWriter.Flush()
1008 differingPeers = smartBanWriter.badPeers
1009 missinggo.CopyExact(&ret, hash.Sum(nil))
1013 func (t *Torrent) haveAnyPieces() bool {
1014 return !t._completedPieces.IsEmpty()
1017 func (t *Torrent) haveAllPieces() bool {
1021 return t._completedPieces.GetCardinality() == bitmap.BitRange(t.numPieces())
1024 func (t *Torrent) havePiece(index pieceIndex) bool {
1025 return t.haveInfo() && t.pieceComplete(index)
1028 func (t *Torrent) maybeDropMutuallyCompletePeer(
1029 // I'm not sure about taking peer here, not all peer implementations actually drop. Maybe that's
1033 if !t.cl.config.DropMutuallyCompletePeers {
1036 if !t.haveAllPieces() {
1039 if all, known := p.peerHasAllPieces(); !(known && all) {
1045 t.logger.WithDefaultLevel(log.Debug).Printf("dropping %v, which is mutually complete", p)
1049 func (t *Torrent) haveChunk(r Request) (ret bool) {
1051 // log.Println("have chunk", r, ret)
1056 if t.pieceComplete(pieceIndex(r.Index)) {
1059 p := &t.pieces[r.Index]
1060 return !p.pendingChunk(r.ChunkSpec, t.chunkSize)
1063 func chunkIndexFromChunkSpec(cs ChunkSpec, chunkSize pp.Integer) chunkIndexType {
1064 return chunkIndexType(cs.Begin / chunkSize)
1067 func (t *Torrent) wantPieceIndex(index pieceIndex) bool {
1068 return t._pendingPieces.Contains(uint32(index))
1071 // A pool of []*PeerConn, to reduce allocations in functions that need to index or sort Torrent
1072 // conns (which is a map).
1073 var peerConnSlices sync.Pool
1075 func getPeerConnSlice(cap int) []*PeerConn {
1076 getInterface := peerConnSlices.Get()
1077 if getInterface == nil {
1078 return make([]*PeerConn, 0, cap)
1080 return getInterface.([]*PeerConn)[:0]
1084 // The worst connection is one that hasn't been sent, or sent anything useful for the longest. A bad
1085 // connection is one that usually sends us unwanted pieces, or has been in the worse half of the
1086 // established connections for more than a minute. This is O(n log n). If there was a way to not
1087 // consider the position of a conn relative to the total number, it could be reduced to O(n).
1088 func (t *Torrent) worstBadConn() (ret *PeerConn) {
1089 wcs := worseConnSlice{conns: t.appendUnclosedConns(getPeerConnSlice(len(t.conns)))}
1090 defer peerConnSlices.Put(wcs.conns)
1093 for wcs.Len() != 0 {
1094 c := heap.Pop(&wcs).(*PeerConn)
1095 if c._stats.ChunksReadWasted.Int64() >= 6 && c._stats.ChunksReadWasted.Int64() > c._stats.ChunksReadUseful.Int64() {
1098 // If the connection is in the worst half of the established
1099 // connection quota and is older than a minute.
1100 if wcs.Len() >= (t.maxEstablishedConns+1)/2 {
1101 // Give connections 1 minute to prove themselves.
1102 if time.Since(c.completedHandshake) > time.Minute {
1110 type PieceStateChange struct {
1115 func (t *Torrent) publishPieceChange(piece pieceIndex) {
1116 t.cl._mu.Defer(func() {
1117 cur := t.pieceState(piece)
1118 p := &t.pieces[piece]
1119 if cur != p.publicPieceState {
1120 p.publicPieceState = cur
1121 t.pieceStateChanges.Publish(PieceStateChange{
1129 func (t *Torrent) pieceNumPendingChunks(piece pieceIndex) pp.Integer {
1130 if t.pieceComplete(piece) {
1133 return pp.Integer(t.pieceNumChunks(piece) - t.pieces[piece].numDirtyChunks())
1136 func (t *Torrent) pieceAllDirty(piece pieceIndex) bool {
1137 return t.pieces[piece].allChunksDirty()
1140 func (t *Torrent) readersChanged() {
1141 t.updateReaderPieces()
1142 t.updateAllPiecePriorities("Torrent.readersChanged")
1145 func (t *Torrent) updateReaderPieces() {
1146 t._readerNowPieces, t._readerReadaheadPieces = t.readerPiecePriorities()
1149 func (t *Torrent) readerPosChanged(from, to pieceRange) {
1153 t.updateReaderPieces()
1154 // Order the ranges, high and low.
1156 if l.begin > h.begin {
1159 if l.end < h.begin {
1160 // Two distinct ranges.
1161 t.updatePiecePriorities(l.begin, l.end, "Torrent.readerPosChanged")
1162 t.updatePiecePriorities(h.begin, h.end, "Torrent.readerPosChanged")
1169 t.updatePiecePriorities(l.begin, end, "Torrent.readerPosChanged")
1173 func (t *Torrent) maybeNewConns() {
1174 // Tickle the accept routine.
1175 t.cl.event.Broadcast()
1179 func (t *Torrent) piecePriorityChanged(piece pieceIndex, reason string) {
1180 if t._pendingPieces.Contains(uint32(piece)) {
1181 t.iterPeers(func(c *Peer) {
1182 // if c.requestState.Interested {
1185 if !c.isLowOnRequests() {
1188 if !c.peerHasPiece(piece) {
1191 if c.requestState.Interested && c.peerChoking && !c.peerAllowedFast.Contains(piece) {
1194 c.updateRequests(reason)
1198 t.publishPieceChange(piece)
1201 func (t *Torrent) updatePiecePriority(piece pieceIndex, reason string) {
1202 if !t.closed.IsSet() {
1203 // It would be possible to filter on pure-priority changes here to avoid churning the piece
1205 t.updatePieceRequestOrder(piece)
1207 p := &t.pieces[piece]
1208 newPrio := p.uncachedPriority()
1209 // t.logger.Printf("torrent %p: piece %d: uncached priority: %v", t, piece, newPrio)
1210 if newPrio == PiecePriorityNone {
1211 if !t._pendingPieces.CheckedRemove(uint32(piece)) {
1215 if !t._pendingPieces.CheckedAdd(uint32(piece)) {
1219 t.piecePriorityChanged(piece, reason)
1222 func (t *Torrent) updateAllPiecePriorities(reason string) {
1223 t.updatePiecePriorities(0, t.numPieces(), reason)
1226 // Update all piece priorities in one hit. This function should have the same
1227 // output as updatePiecePriority, but across all pieces.
1228 func (t *Torrent) updatePiecePriorities(begin, end pieceIndex, reason string) {
1229 for i := begin; i < end; i++ {
1230 t.updatePiecePriority(i, reason)
1234 // Returns the range of pieces [begin, end) that contains the extent of bytes.
1235 func (t *Torrent) byteRegionPieces(off, size int64) (begin, end pieceIndex) {
1236 if off >= t.length() {
1246 begin = pieceIndex(off / t.info.PieceLength)
1247 end = pieceIndex((off + size + t.info.PieceLength - 1) / t.info.PieceLength)
1248 if end > pieceIndex(t.info.NumPieces()) {
1249 end = pieceIndex(t.info.NumPieces())
1254 // Returns true if all iterations complete without breaking. Returns the read regions for all
1255 // readers. The reader regions should not be merged as some callers depend on this method to
1256 // enumerate readers.
1257 func (t *Torrent) forReaderOffsetPieces(f func(begin, end pieceIndex) (more bool)) (all bool) {
1258 for r := range t.readers {
1260 if p.begin >= p.end {
1263 if !f(p.begin, p.end) {
1270 func (t *Torrent) piecePriority(piece pieceIndex) piecePriority {
1271 return t.piece(piece).uncachedPriority()
1274 func (t *Torrent) pendRequest(req RequestIndex) {
1275 t.piece(t.pieceIndexOfRequestIndex(req)).pendChunkIndex(req % t.chunksPerRegularPiece())
1278 func (t *Torrent) pieceCompletionChanged(piece pieceIndex, reason string) {
1279 t.cl.event.Broadcast()
1280 if t.pieceComplete(piece) {
1281 t.onPieceCompleted(piece)
1283 t.onIncompletePiece(piece)
1285 t.updatePiecePriority(piece, reason)
1288 func (t *Torrent) numReceivedConns() (ret int) {
1289 for c := range t.conns {
1290 if c.Discovery == PeerSourceIncoming {
1297 func (t *Torrent) maxHalfOpen() int {
1298 // Note that if we somehow exceed the maximum established conns, we want
1299 // the negative value to have an effect.
1300 establishedHeadroom := int64(t.maxEstablishedConns - len(t.conns))
1301 extraIncoming := int64(t.numReceivedConns() - t.maxEstablishedConns/2)
1302 // We want to allow some experimentation with new peers, and to try to
1303 // upset an oversupply of received connections.
1304 return int(min(max(5, extraIncoming)+establishedHeadroom, int64(t.cl.config.HalfOpenConnsPerTorrent)))
1307 func (t *Torrent) openNewConns() (initiated int) {
1308 defer t.updateWantPeersEvent()
1309 for t.peers.Len() != 0 {
1313 if len(t.halfOpen) >= t.maxHalfOpen() {
1316 if len(t.cl.dialers) == 0 {
1319 if t.cl.numHalfOpen >= t.cl.config.TotalHalfOpenConns {
1322 p := t.peers.PopMax()
1329 func (t *Torrent) updatePieceCompletion(piece pieceIndex) bool {
1331 uncached := t.pieceCompleteUncached(piece)
1332 cached := p.completion()
1333 changed := cached != uncached
1334 complete := uncached.Complete
1335 p.storageCompletionOk = uncached.Ok
1338 t._completedPieces.Add(x)
1341 t._completedPieces.Remove(x)
1343 p.t.updatePieceRequestOrder(piece)
1345 if complete && len(p.dirtiers) != 0 {
1346 t.logger.Printf("marked piece %v complete but still has dirtiers", piece)
1349 log.Fstr("piece %d completion changed: %+v -> %+v", piece, cached, uncached).LogLevel(log.Debug, t.logger)
1350 t.pieceCompletionChanged(piece, "Torrent.updatePieceCompletion")
1355 // Non-blocking read. Client lock is not required.
1356 func (t *Torrent) readAt(b []byte, off int64) (n int, err error) {
1358 p := &t.pieces[off/t.info.PieceLength]
1359 p.waitNoPendingWrites()
1361 n1, err = p.Storage().ReadAt(b, off-p.Info().Offset())
1372 // Returns an error if the metadata was completed, but couldn't be set for some reason. Blame it on
1373 // the last peer to contribute. TODO: Actually we shouldn't blame peers for failure to open storage
1374 // etc. Also we should probably cached metadata pieces per-Peer, to isolate failure appropriately.
1375 func (t *Torrent) maybeCompleteMetadata() error {
1380 if !t.haveAllMetadataPieces() {
1381 // Don't have enough metadata pieces.
1384 err := t.setInfoBytesLocked(t.metadataBytes)
1386 t.invalidateMetadata()
1387 return fmt.Errorf("error setting info bytes: %s", err)
1389 if t.cl.config.Debug {
1390 t.logger.Printf("%s: got metadata from peers", t)
1395 func (t *Torrent) readerPiecePriorities() (now, readahead bitmap.Bitmap) {
1396 t.forReaderOffsetPieces(func(begin, end pieceIndex) bool {
1398 now.Add(bitmap.BitIndex(begin))
1399 readahead.AddRange(bitmap.BitRange(begin)+1, bitmap.BitRange(end))
1406 func (t *Torrent) needData() bool {
1407 if t.closed.IsSet() {
1413 return !t._pendingPieces.IsEmpty()
1416 func appendMissingStrings(old, new []string) (ret []string) {
1419 for _, n := range new {
1420 for _, o := range old {
1425 ret = append(ret, n)
1430 func appendMissingTrackerTiers(existing [][]string, minNumTiers int) (ret [][]string) {
1432 for minNumTiers > len(ret) {
1433 ret = append(ret, nil)
1438 func (t *Torrent) addTrackers(announceList [][]string) {
1439 fullAnnounceList := &t.metainfo.AnnounceList
1440 t.metainfo.AnnounceList = appendMissingTrackerTiers(*fullAnnounceList, len(announceList))
1441 for tierIndex, trackerURLs := range announceList {
1442 (*fullAnnounceList)[tierIndex] = appendMissingStrings((*fullAnnounceList)[tierIndex], trackerURLs)
1444 t.startMissingTrackerScrapers()
1445 t.updateWantPeersEvent()
1448 // Don't call this before the info is available.
1449 func (t *Torrent) bytesCompleted() int64 {
1453 return t.length() - t.bytesLeft()
1456 func (t *Torrent) SetInfoBytes(b []byte) (err error) {
1459 return t.setInfoBytesLocked(b)
1462 // Returns true if connection is removed from torrent.Conns.
1463 func (t *Torrent) deletePeerConn(c *PeerConn) (ret bool) {
1464 if !c.closed.IsSet() {
1465 panic("connection is not closed")
1466 // There are behaviours prevented by the closed state that will fail
1467 // if the connection has been deleted.
1471 // Avoid adding a drop event more than once. Probably we should track whether we've generated
1472 // the drop event against the PexConnState instead.
1474 if !t.cl.config.DisablePEX {
1478 torrent.Add("deleted connections", 1)
1479 c.deleteAllRequests("Torrent.deletePeerConn")
1480 t.assertPendingRequests()
1481 if t.numActivePeers() == 0 && len(t.connsWithAllPieces) != 0 {
1482 panic(t.connsWithAllPieces)
1487 func (t *Torrent) decPeerPieceAvailability(p *Peer) {
1488 if t.deleteConnWithAllPieces(p) {
1494 p.peerPieces().Iterate(func(i uint32) bool {
1495 p.t.decPieceAvailability(pieceIndex(i))
1500 func (t *Torrent) assertPendingRequests() {
1504 // var actual pendingRequests
1505 // if t.haveInfo() {
1506 // actual.m = make([]int, t.numChunks())
1508 // t.iterPeers(func(p *Peer) {
1509 // p.requestState.Requests.Iterate(func(x uint32) bool {
1514 // diff := cmp.Diff(actual.m, t.pendingRequests.m)
1520 func (t *Torrent) dropConnection(c *PeerConn) {
1521 t.cl.event.Broadcast()
1523 if t.deletePeerConn(c) {
1528 // Peers as in contact information for dialing out.
1529 func (t *Torrent) wantPeers() bool {
1530 if t.closed.IsSet() {
1533 if t.peers.Len() > t.cl.config.TorrentPeersLowWater {
1536 return t.wantConns()
1539 func (t *Torrent) updateWantPeersEvent() {
1541 t.wantPeersEvent.Set()
1543 t.wantPeersEvent.Clear()
1547 // Returns whether the client should make effort to seed the torrent.
1548 func (t *Torrent) seeding() bool {
1550 if t.closed.IsSet() {
1553 if t.dataUploadDisallowed {
1556 if cl.config.NoUpload {
1559 if !cl.config.Seed {
1562 if cl.config.DisableAggressiveUpload && t.needData() {
1568 func (t *Torrent) onWebRtcConn(
1569 c datachannel.ReadWriteCloser,
1570 dcc webtorrent.DataChannelContext,
1573 netConn := webrtcNetConn{
1575 DataChannelContext: dcc,
1577 peerRemoteAddr := netConn.RemoteAddr()
1578 //t.logger.Levelf(log.Critical, "onWebRtcConn remote addr: %v", peerRemoteAddr)
1579 if t.cl.badPeerAddr(peerRemoteAddr) {
1582 localAddrIpPort := missinggo.IpPortFromNetAddr(netConn.LocalAddr())
1583 pc, err := t.cl.initiateProtocolHandshakes(
1584 context.Background(),
1589 outgoing: dcc.LocalOffered,
1590 remoteAddr: peerRemoteAddr,
1591 localPublicAddr: localAddrIpPort,
1592 network: webrtcNetwork,
1593 connString: fmt.Sprintf("webrtc offer_id %x: %v", dcc.OfferId, regularNetConnPeerConnConnString(netConn)),
1597 t.logger.WithDefaultLevel(log.Error).Printf("error in handshaking webrtc connection: %v", err)
1600 if dcc.LocalOffered {
1601 pc.Discovery = PeerSourceTracker
1603 pc.Discovery = PeerSourceIncoming
1605 pc.conn.SetWriteDeadline(time.Time{})
1608 err = t.cl.runHandshookConn(pc, t)
1610 t.logger.WithDefaultLevel(log.Debug).Printf("error running handshook webrtc conn: %v", err)
1614 func (t *Torrent) logRunHandshookConn(pc *PeerConn, logAll bool, level log.Level) {
1615 err := t.cl.runHandshookConn(pc, t)
1616 if err != nil || logAll {
1617 t.logger.WithDefaultLevel(level).Printf("error running handshook conn: %v", err)
1621 func (t *Torrent) runHandshookConnLoggingErr(pc *PeerConn) {
1622 t.logRunHandshookConn(pc, false, log.Debug)
1625 func (t *Torrent) startWebsocketAnnouncer(u url.URL) torrentTrackerAnnouncer {
1626 wtc, release := t.cl.websocketTrackers.Get(u.String(), t.infoHash)
1627 // This needs to run before the Torrent is dropped from the Client, to prevent a new webtorrent.TrackerClient for
1628 // the same info hash before the old one is cleaned up.
1629 t.onClose = append(t.onClose, release)
1630 wst := websocketTrackerStatus{u, wtc}
1632 err := wtc.Announce(tracker.Started, t.infoHash)
1634 t.logger.WithDefaultLevel(log.Warning).Printf(
1635 "error in initial announce to %q: %v",
1643 func (t *Torrent) startScrapingTracker(_url string) {
1647 u, err := url.Parse(_url)
1649 // URLs with a leading '*' appear to be a uTorrent convention to
1650 // disable trackers.
1652 log.Str("error parsing tracker url").AddValues("url", _url).Log(t.logger)
1656 if u.Scheme == "udp" {
1658 t.startScrapingTracker(u.String())
1660 t.startScrapingTracker(u.String())
1663 if _, ok := t.trackerAnnouncers[_url]; ok {
1666 sl := func() torrentTrackerAnnouncer {
1669 if t.cl.config.DisableWebtorrent {
1672 return t.startWebsocketAnnouncer(*u)
1674 if t.cl.config.DisableIPv4Peers || t.cl.config.DisableIPv4 {
1678 if t.cl.config.DisableIPv6 {
1682 newAnnouncer := &trackerScraper{
1685 lookupTrackerIp: t.cl.config.LookupTrackerIp,
1687 go newAnnouncer.Run()
1693 if t.trackerAnnouncers == nil {
1694 t.trackerAnnouncers = make(map[string]torrentTrackerAnnouncer)
1696 t.trackerAnnouncers[_url] = sl
1699 // Adds and starts tracker scrapers for tracker URLs that aren't already
1701 func (t *Torrent) startMissingTrackerScrapers() {
1702 if t.cl.config.DisableTrackers {
1705 t.startScrapingTracker(t.metainfo.Announce)
1706 for _, tier := range t.metainfo.AnnounceList {
1707 for _, url := range tier {
1708 t.startScrapingTracker(url)
1713 // Returns an AnnounceRequest with fields filled out to defaults and current
1715 func (t *Torrent) announceRequest(event tracker.AnnounceEvent) tracker.AnnounceRequest {
1716 // Note that IPAddress is not set. It's set for UDP inside the tracker code, since it's
1717 // dependent on the network in use.
1718 return tracker.AnnounceRequest{
1720 NumWant: func() int32 {
1721 if t.wantPeers() && len(t.cl.dialers) > 0 {
1722 return 200 // Win has UDP packet limit. See: https://github.com/anacrolix/torrent/issues/764
1727 Port: uint16(t.cl.incomingPeerPort()),
1728 PeerId: t.cl.peerID,
1729 InfoHash: t.infoHash,
1730 Key: t.cl.announceKey(),
1732 // The following are vaguely described in BEP 3.
1734 Left: t.bytesLeftAnnounce(),
1735 Uploaded: t.stats.BytesWrittenData.Int64(),
1736 // There's no mention of wasted or unwanted download in the BEP.
1737 Downloaded: t.stats.BytesReadUsefulData.Int64(),
1741 // Adds peers revealed in an announce until the announce ends, or we have
1743 func (t *Torrent) consumeDhtAnnouncePeers(pvs <-chan dht.PeersValues) {
1745 for v := range pvs {
1748 for _, cp := range v.Peers {
1750 // Can't do anything with this.
1753 if t.addPeer(PeerInfo{
1754 Addr: ipPortAddr{cp.IP, cp.Port},
1755 Source: PeerSourceDhtGetPeers,
1762 // log.Printf("added %v peers from dht for %v", added, t.InfoHash().HexString())
1767 // Announce using the provided DHT server. Peers are consumed automatically. done is closed when the
1768 // announce ends. stop will force the announce to end.
1769 func (t *Torrent) AnnounceToDht(s DhtServer) (done <-chan struct{}, stop func(), err error) {
1770 ps, err := s.Announce(t.infoHash, t.cl.incomingPeerPort(), true)
1774 _done := make(chan struct{})
1778 t.consumeDhtAnnouncePeers(ps.Peers())
1784 func (t *Torrent) timeboxedAnnounceToDht(s DhtServer) error {
1785 _, stop, err := t.AnnounceToDht(s)
1790 case <-t.closed.Done():
1791 case <-time.After(5 * time.Minute):
1797 func (t *Torrent) dhtAnnouncer(s DhtServer) {
1803 if t.closed.IsSet() {
1806 // We're also announcing ourselves as a listener, so we don't just want peer addresses.
1807 // TODO: We can include the announce_peer step depending on whether we can receive
1808 // inbound connections. We should probably only announce once every 15 mins too.
1812 // TODO: Determine if there's a listener on the port we're announcing.
1813 if len(cl.dialers) == 0 && len(cl.listeners) == 0 {
1824 err := t.timeboxedAnnounceToDht(s)
1826 t.logger.WithDefaultLevel(log.Warning).Printf("error announcing %q to DHT: %s", t, err)
1832 func (t *Torrent) addPeers(peers []PeerInfo) (added int) {
1833 for _, p := range peers {
1841 // The returned TorrentStats may require alignment in memory. See
1842 // https://github.com/anacrolix/torrent/issues/383.
1843 func (t *Torrent) Stats() TorrentStats {
1845 defer t.cl.rUnlock()
1846 return t.statsLocked()
1849 func (t *Torrent) statsLocked() (ret TorrentStats) {
1850 ret.ActivePeers = len(t.conns)
1851 ret.HalfOpenPeers = len(t.halfOpen)
1852 ret.PendingPeers = t.peers.Len()
1853 ret.TotalPeers = t.numTotalPeers()
1854 ret.ConnectedSeeders = 0
1855 for c := range t.conns {
1856 if all, ok := c.peerHasAllPieces(); all && ok {
1857 ret.ConnectedSeeders++
1860 ret.ConnStats = t.stats.Copy()
1861 ret.PiecesComplete = t.numPiecesCompleted()
1865 // The total number of peers in the torrent.
1866 func (t *Torrent) numTotalPeers() int {
1867 peers := make(map[string]struct{})
1868 for conn := range t.conns {
1869 ra := conn.conn.RemoteAddr()
1871 // It's been closed and doesn't support RemoteAddr.
1874 peers[ra.String()] = struct{}{}
1876 for addr := range t.halfOpen {
1877 peers[addr] = struct{}{}
1879 t.peers.Each(func(peer PeerInfo) {
1880 peers[peer.Addr.String()] = struct{}{}
1885 // Reconcile bytes transferred before connection was associated with a
1887 func (t *Torrent) reconcileHandshakeStats(c *PeerConn) {
1888 if c._stats != (ConnStats{
1889 // Handshakes should only increment these fields:
1890 BytesWritten: c._stats.BytesWritten,
1891 BytesRead: c._stats.BytesRead,
1895 c.postHandshakeStats(func(cs *ConnStats) {
1896 cs.BytesRead.Add(c._stats.BytesRead.Int64())
1897 cs.BytesWritten.Add(c._stats.BytesWritten.Int64())
1899 c.reconciledHandshakeStats = true
1902 // Returns true if the connection is added.
1903 func (t *Torrent) addPeerConn(c *PeerConn) (err error) {
1906 torrent.Add("added connections", 1)
1909 if t.closed.IsSet() {
1910 return errors.New("torrent closed")
1912 for c0 := range t.conns {
1913 if c.PeerID != c0.PeerID {
1916 if !t.cl.config.DropDuplicatePeerIds {
1919 if c.hasPreferredNetworkOver(c0) {
1921 t.deletePeerConn(c0)
1923 return errors.New("existing connection preferred")
1926 if len(t.conns) >= t.maxEstablishedConns {
1927 c := t.worstBadConn()
1929 return errors.New("don't want conns")
1934 if len(t.conns) >= t.maxEstablishedConns {
1937 t.conns[c] = struct{}{}
1938 if !t.cl.config.DisablePEX && !c.PeerExtensionBytes.SupportsExtended() {
1939 t.pex.Add(c) // as no further extended handshake expected
1944 func (t *Torrent) wantConns() bool {
1945 if !t.networkingEnabled.Bool() {
1948 if t.closed.IsSet() {
1951 if !t.needData() && (!t.seeding() || !t.haveAnyPieces()) {
1954 return len(t.conns) < t.maxEstablishedConns || t.worstBadConn() != nil
1957 func (t *Torrent) SetMaxEstablishedConns(max int) (oldMax int) {
1960 oldMax = t.maxEstablishedConns
1961 t.maxEstablishedConns = max
1962 wcs := worseConnSlice{
1963 conns: t.appendConns(nil, func(*PeerConn) bool {
1969 for len(t.conns) > t.maxEstablishedConns && wcs.Len() > 0 {
1970 t.dropConnection(heap.Pop(&wcs).(*PeerConn))
1976 func (t *Torrent) pieceHashed(piece pieceIndex, passed bool, hashIoErr error) {
1977 t.logger.LazyLog(log.Debug, func() log.Msg {
1978 return log.Fstr("hashed piece %d (passed=%t)", piece, passed)
1982 t.cl.event.Broadcast()
1983 if t.closed.IsSet() {
1987 // Don't score the first time a piece is hashed, it could be an initial check.
1988 if p.storageCompletionOk {
1990 pieceHashedCorrect.Add(1)
1993 "piece %d failed hash: %d connections contributed", piece, len(p.dirtiers),
1994 ).AddValues(t, p).LogLevel(
1996 log.Debug, t.logger)
1998 pieceHashedNotCorrect.Add(1)
2003 t.publishPieceChange(piece)
2006 t.publishPieceChange(piece)
2010 if len(p.dirtiers) != 0 {
2011 // Don't increment stats above connection-level for every involved connection.
2012 t.allStats((*ConnStats).incrementPiecesDirtiedGood)
2014 for c := range p.dirtiers {
2015 c._stats.incrementPiecesDirtiedGood()
2017 t.clearPieceTouchers(piece)
2018 hasDirty := p.hasDirtyChunks()
2021 p.Flush() // You can be synchronous here!
2023 err := p.Storage().MarkComplete()
2025 t.logger.Printf("%T: error marking piece complete %d: %s", t.storage, piece, err)
2029 if t.closed.IsSet() {
2032 t.pendAllChunkSpecs(piece)
2034 if len(p.dirtiers) != 0 && p.allChunksDirty() && hashIoErr == nil {
2035 // Peers contributed to all the data for this piece hash failure, and the failure was
2036 // not due to errors in the storage (such as data being dropped in a cache).
2038 // Increment Torrent and above stats, and then specific connections.
2039 t.allStats((*ConnStats).incrementPiecesDirtiedBad)
2040 for c := range p.dirtiers {
2041 // Y u do dis peer?!
2042 c.stats().incrementPiecesDirtiedBad()
2045 bannableTouchers := make([]*Peer, 0, len(p.dirtiers))
2046 for c := range p.dirtiers {
2048 bannableTouchers = append(bannableTouchers, c)
2051 t.clearPieceTouchers(piece)
2052 slices.Sort(bannableTouchers, connLessTrusted)
2054 if t.cl.config.Debug {
2056 "bannable conns by trust for piece %d: %v",
2058 func() (ret []connectionTrust) {
2059 for _, c := range bannableTouchers {
2060 ret = append(ret, c.trust())
2067 if len(bannableTouchers) >= 1 {
2068 c := bannableTouchers[0]
2069 if len(bannableTouchers) != 1 {
2070 t.logger.Levelf(log.Warning, "would have banned %v for touching piece %v after failed piece check", c.remoteIp(), piece)
2072 // Turns out it's still useful to ban peers like this because if there's only a
2073 // single peer for a piece, and we never progress that piece to completion, we
2074 // will never smart-ban them. Discovered in
2075 // https://github.com/anacrolix/torrent/issues/715.
2076 t.logger.Levelf(log.Warning, "banning %v for being sole dirtier of piece %v after failed piece check", c, piece)
2081 t.onIncompletePiece(piece)
2082 p.Storage().MarkNotComplete()
2084 t.updatePieceCompletion(piece)
2087 func (t *Torrent) cancelRequestsForPiece(piece pieceIndex) {
2088 start := t.pieceRequestIndexOffset(piece)
2089 end := start + t.pieceNumChunks(piece)
2090 for ri := start; ri < end; ri++ {
2095 func (t *Torrent) onPieceCompleted(piece pieceIndex) {
2096 t.pendAllChunkSpecs(piece)
2097 t.cancelRequestsForPiece(piece)
2098 t.piece(piece).readerCond.Broadcast()
2099 for conn := range t.conns {
2101 t.maybeDropMutuallyCompletePeer(&conn.Peer)
2105 // Called when a piece is found to be not complete.
2106 func (t *Torrent) onIncompletePiece(piece pieceIndex) {
2107 if t.pieceAllDirty(piece) {
2108 t.pendAllChunkSpecs(piece)
2110 if !t.wantPieceIndex(piece) {
2111 // t.logger.Printf("piece %d incomplete and unwanted", piece)
2114 // We could drop any connections that we told we have a piece that we
2115 // don't here. But there's a test failure, and it seems clients don't care
2116 // if you request pieces that you already claim to have. Pruning bad
2117 // connections might just remove any connections that aren't treating us
2118 // favourably anyway.
2120 // for c := range t.conns {
2121 // if c.sentHave(piece) {
2125 t.iterPeers(func(conn *Peer) {
2126 if conn.peerHasPiece(piece) {
2127 conn.updateRequests("piece incomplete")
2132 func (t *Torrent) tryCreateMorePieceHashers() {
2133 for !t.closed.IsSet() && t.activePieceHashes < 2 && t.tryCreatePieceHasher() {
2137 func (t *Torrent) tryCreatePieceHasher() bool {
2138 if t.storage == nil {
2141 pi, ok := t.getPieceToHash()
2146 t.piecesQueuedForHash.Remove(bitmap.BitIndex(pi))
2148 t.publishPieceChange(pi)
2149 t.updatePiecePriority(pi, "Torrent.tryCreatePieceHasher")
2150 t.storageLock.RLock()
2151 t.activePieceHashes++
2152 go t.pieceHasher(pi)
2156 func (t *Torrent) getPieceToHash() (ret pieceIndex, ok bool) {
2157 t.piecesQueuedForHash.IterTyped(func(i pieceIndex) bool {
2158 if t.piece(i).hashing {
2168 func (t *Torrent) dropBannedPeers() {
2169 t.iterPeers(func(p *Peer) {
2170 remoteIp := p.remoteIp()
2171 if remoteIp == nil {
2172 if p.bannableAddr.Ok {
2173 t.logger.WithDefaultLevel(log.Debug).Printf("can't get remote ip for peer %v", p)
2177 netipAddr := netip.MustParseAddr(remoteIp.String())
2178 if Some(netipAddr) != p.bannableAddr {
2179 t.logger.WithDefaultLevel(log.Debug).Printf(
2180 "peer remote ip does not match its bannable addr [peer=%v, remote ip=%v, bannable addr=%v]",
2181 p, remoteIp, p.bannableAddr)
2183 if _, ok := t.cl.badPeerIPs[netipAddr]; ok {
2184 // Should this be a close?
2186 t.logger.WithDefaultLevel(log.Debug).Printf("dropped %v for banned remote IP %v", p, netipAddr)
2191 func (t *Torrent) pieceHasher(index pieceIndex) {
2193 sum, failedPeers, copyErr := t.hashPiece(index)
2194 correct := sum == *p.hash
2198 log.Fmsg("piece %v (%s) hash failure copy error: %v", p, p.hash.HexString(), copyErr).Log(t.logger)
2200 t.storageLock.RUnlock()
2204 for peer := range failedPeers {
2205 t.cl.banPeerIP(peer.AsSlice())
2206 t.logger.WithDefaultLevel(log.Debug).Printf("smart banned %v for piece %v", peer, index)
2209 for ri := t.pieceRequestIndexOffset(index); ri < t.pieceRequestIndexOffset(index+1); ri++ {
2210 t.smartBanCache.ForgetBlock(ri)
2214 t.pieceHashed(index, correct, copyErr)
2215 t.updatePiecePriority(index, "Torrent.pieceHasher")
2216 t.activePieceHashes--
2217 t.tryCreateMorePieceHashers()
2220 // Return the connections that touched a piece, and clear the entries while doing it.
2221 func (t *Torrent) clearPieceTouchers(pi pieceIndex) {
2223 for c := range p.dirtiers {
2224 delete(c.peerTouchedPieces, pi)
2225 delete(p.dirtiers, c)
2229 func (t *Torrent) peersAsSlice() (ret []*Peer) {
2230 t.iterPeers(func(p *Peer) {
2231 ret = append(ret, p)
2236 func (t *Torrent) queuePieceCheck(pieceIndex pieceIndex) {
2237 piece := t.piece(pieceIndex)
2238 if piece.queuedForHash() {
2241 t.piecesQueuedForHash.Add(bitmap.BitIndex(pieceIndex))
2242 t.publishPieceChange(pieceIndex)
2243 t.updatePiecePriority(pieceIndex, "Torrent.queuePieceCheck")
2244 t.tryCreateMorePieceHashers()
2247 // Forces all the pieces to be re-hashed. See also Piece.VerifyData. This should not be called
2248 // before the Info is available.
2249 func (t *Torrent) VerifyData() {
2250 for i := pieceIndex(0); i < t.NumPieces(); i++ {
2251 t.Piece(i).VerifyData()
2255 // Start the process of connecting to the given peer for the given torrent if appropriate.
2256 func (t *Torrent) initiateConn(peer PeerInfo) {
2257 if peer.Id == t.cl.peerID {
2260 if t.cl.badPeerAddr(peer.Addr) && !peer.Trusted {
2264 if t.addrActive(addr.String()) {
2268 t.halfOpen[addr.String()] = peer
2269 go t.cl.outgoingConnection(t, addr, peer.Source, peer.Trusted)
2272 // Adds a trusted, pending peer for each of the given Client's addresses. Typically used in tests to
2273 // quickly make one Client visible to the Torrent of another Client.
2274 func (t *Torrent) AddClientPeer(cl *Client) int {
2275 return t.AddPeers(func() (ps []PeerInfo) {
2276 for _, la := range cl.ListenAddrs() {
2277 ps = append(ps, PeerInfo{
2286 // All stats that include this Torrent. Useful when we want to increment ConnStats but not for every
2288 func (t *Torrent) allStats(f func(*ConnStats)) {
2293 func (t *Torrent) hashingPiece(i pieceIndex) bool {
2294 return t.pieces[i].hashing
2297 func (t *Torrent) pieceQueuedForHash(i pieceIndex) bool {
2298 return t.piecesQueuedForHash.Get(bitmap.BitIndex(i))
2301 func (t *Torrent) dialTimeout() time.Duration {
2302 return reducedDialTimeout(t.cl.config.MinDialTimeout, t.cl.config.NominalDialTimeout, t.cl.config.HalfOpenConnsPerTorrent, t.peers.Len())
2305 func (t *Torrent) piece(i int) *Piece {
2309 func (t *Torrent) onWriteChunkErr(err error) {
2310 if t.userOnWriteChunkErr != nil {
2311 go t.userOnWriteChunkErr(err)
2314 t.logger.WithDefaultLevel(log.Critical).Printf("default chunk write error handler: disabling data download")
2315 t.disallowDataDownloadLocked()
2318 func (t *Torrent) DisallowDataDownload() {
2319 t.disallowDataDownloadLocked()
2322 func (t *Torrent) disallowDataDownloadLocked() {
2323 t.dataDownloadDisallowed.Set()
2326 func (t *Torrent) AllowDataDownload() {
2327 t.dataDownloadDisallowed.Clear()
2330 // Enables uploading data, if it was disabled.
2331 func (t *Torrent) AllowDataUpload() {
2334 t.dataUploadDisallowed = false
2335 for c := range t.conns {
2336 c.updateRequests("allow data upload")
2340 // Disables uploading data, if it was enabled.
2341 func (t *Torrent) DisallowDataUpload() {
2344 t.dataUploadDisallowed = true
2345 for c := range t.conns {
2346 // TODO: This doesn't look right. Shouldn't we tickle writers to choke peers or something instead?
2347 c.updateRequests("disallow data upload")
2351 // Sets a handler that is called if there's an error writing a chunk to local storage. By default,
2352 // or if nil, a critical message is logged, and data download is disabled.
2353 func (t *Torrent) SetOnWriteChunkError(f func(error)) {
2356 t.userOnWriteChunkErr = f
2359 func (t *Torrent) iterPeers(f func(p *Peer)) {
2360 for pc := range t.conns {
2363 for _, ws := range t.webSeeds {
2368 func (t *Torrent) callbacks() *Callbacks {
2369 return &t.cl.config.Callbacks
2372 type AddWebSeedsOpt func(*webseed.Client)
2374 // Sets the WebSeed trailing path escaper for a webseed.Client.
2375 func WebSeedPathEscaper(custom webseed.PathEscaper) AddWebSeedsOpt {
2376 return func(c *webseed.Client) {
2377 c.PathEscaper = custom
2381 func (t *Torrent) AddWebSeeds(urls []string, opts ...AddWebSeedsOpt) {
2384 for _, u := range urls {
2385 t.addWebSeed(u, opts...)
2389 func (t *Torrent) addWebSeed(url string, opts ...AddWebSeedsOpt) {
2390 if t.cl.config.DisableWebseeds {
2393 if _, ok := t.webSeeds[url]; ok {
2396 // I don't think Go http supports pipelining requests. However, we can have more ready to go
2397 // right away. This value should be some multiple of the number of connections to a host. I
2398 // would expect that double maxRequests plus a bit would be appropriate. This value is based on
2399 // downloading Sintel (08ada5a7a6183aae1e09d831df6748d566095a10) from
2400 // "https://webtorrent.io/torrents/".
2401 const maxRequests = 16
2407 reconciledHandshakeStats: true,
2408 // This should affect how often we have to recompute requests for this peer. Note that
2409 // because we can request more than 1 thing at a time over HTTP, we will hit the low
2410 // requests mark more often, so recomputation is probably sooner than with regular peer
2411 // conns. ~4x maxRequests would be about right.
2412 PeerMaxRequests: 128,
2413 // TODO: Set ban prefix?
2414 RemoteAddr: remoteAddrFromUrl(url),
2415 callbacks: t.callbacks(),
2417 client: webseed.Client{
2418 HttpClient: t.cl.httpClient,
2420 ResponseBodyWrapper: func(r io.Reader) io.Reader {
2421 return &rateLimitedReader{
2422 l: t.cl.config.DownloadRateLimiter,
2427 activeRequests: make(map[Request]webseed.Request, maxRequests),
2428 maxRequests: maxRequests,
2430 ws.peer.initRequestState()
2431 for _, opt := range opts {
2434 ws.peer.initUpdateRequestsTimer()
2435 ws.requesterCond.L = t.cl.locker()
2436 for i := 0; i < maxRequests; i += 1 {
2439 for _, f := range t.callbacks().NewPeer {
2442 ws.peer.logger = t.logger.WithContextValue(&ws)
2443 ws.peer.peerImpl = &ws
2445 ws.onGotInfo(t.info)
2447 t.webSeeds[url] = &ws.peer
2450 func (t *Torrent) peerIsActive(p *Peer) (active bool) {
2451 t.iterPeers(func(p1 *Peer) {
2459 func (t *Torrent) requestIndexToRequest(ri RequestIndex) Request {
2460 index := t.pieceIndexOfRequestIndex(ri)
2463 t.piece(index).chunkIndexSpec(ri % t.chunksPerRegularPiece()),
2467 func (t *Torrent) requestIndexFromRequest(r Request) RequestIndex {
2468 return t.pieceRequestIndexOffset(pieceIndex(r.Index)) + RequestIndex(r.Begin/t.chunkSize)
2471 func (t *Torrent) pieceRequestIndexOffset(piece pieceIndex) RequestIndex {
2472 return RequestIndex(piece) * t.chunksPerRegularPiece()
2475 func (t *Torrent) updateComplete() {
2476 t.Complete.SetBool(t.haveAllPieces())
2479 func (t *Torrent) cancelRequest(r RequestIndex) *Peer {
2480 p := t.requestingPeer(r)
2484 // TODO: This is a check that an old invariant holds. It can be removed after some testing.
2485 //delete(t.pendingRequests, r)
2486 if _, ok := t.requestState[r]; ok {
2487 panic("expected request state to be gone")
2492 func (t *Torrent) requestingPeer(r RequestIndex) *Peer {
2493 return t.requestState[r].peer
2496 func (t *Torrent) addConnWithAllPieces(p *Peer) {
2497 if t.connsWithAllPieces == nil {
2498 t.connsWithAllPieces = make(map[*Peer]struct{}, t.maxEstablishedConns)
2500 t.connsWithAllPieces[p] = struct{}{}
2503 func (t *Torrent) deleteConnWithAllPieces(p *Peer) bool {
2504 _, ok := t.connsWithAllPieces[p]
2505 delete(t.connsWithAllPieces, p)
2509 func (t *Torrent) numActivePeers() int {
2510 return len(t.conns) + len(t.webSeeds)
2513 func (t *Torrent) hasStorageCap() bool {
2514 f := t.storage.Capacity
2522 func (t *Torrent) pieceIndexOfRequestIndex(ri RequestIndex) pieceIndex {
2523 return pieceIndex(ri / t.chunksPerRegularPiece())
2526 func (t *Torrent) iterUndirtiedRequestIndexesInPiece(
2527 reuseIter *typedRoaring.Iterator[RequestIndex],
2529 f func(RequestIndex),
2531 reuseIter.Initialize(&t.dirtyChunks)
2532 pieceRequestIndexOffset := t.pieceRequestIndexOffset(piece)
2533 iterBitmapUnsetInRange(
2535 pieceRequestIndexOffset, pieceRequestIndexOffset+t.pieceNumChunks(piece),
2540 type requestState struct {