package torrent import ( "fmt" "sync" "github.com/anacrolix/missinggo/bitmap" "github.com/anacrolix/torrent/metainfo" pp "github.com/anacrolix/torrent/peer_protocol" "github.com/anacrolix/torrent/storage" ) // Piece priority describes the importance of obtaining a particular piece. type piecePriority byte func (pp *piecePriority) Raise(maybe piecePriority) { if maybe > *pp { *pp = maybe } } const ( PiecePriorityNone piecePriority = iota // Not wanted. PiecePriorityNormal // Wanted. PiecePriorityReadahead // May be required soon. // Succeeds a piece where a read occurred. Currently the same as Now, apparently due to issues with caching. PiecePriorityNext PiecePriorityNow // A Reader is reading in this piece. ) type Piece struct { // The completed piece SHA1 hash, from the metainfo "pieces" field. hash metainfo.Hash t *Torrent index int // Chunks we've written to since the last check. The chunk offset and // length can be determined by the request chunkSize in use. dirtyChunks bitmap.Bitmap hashing bool everHashed bool numVerifies int64 storageCompletionOk bool publicPieceState PieceState priority piecePriority pendingWritesMutex sync.Mutex pendingWrites int noPendingWrites sync.Cond } func (p *Piece) String() string { return fmt.Sprintf("%s/%d", p.t.infoHash.HexString(), p.index) } func (p *Piece) Info() metainfo.Piece { return p.t.info.Piece(p.index) } func (p *Piece) Storage() storage.Piece { return p.t.storage.Piece(p.Info()) } func (p *Piece) pendingChunkIndex(chunkIndex int) bool { return !p.dirtyChunks.Contains(chunkIndex) } func (p *Piece) pendingChunk(cs chunkSpec, chunkSize pp.Integer) bool { return p.pendingChunkIndex(chunkIndex(cs, chunkSize)) } func (p *Piece) hasDirtyChunks() bool { return p.dirtyChunks.Len() != 0 } func (p *Piece) numDirtyChunks() (ret int) { return p.dirtyChunks.Len() } func (p *Piece) unpendChunkIndex(i int) { p.dirtyChunks.Add(i) } func (p *Piece) pendChunkIndex(i int) { p.dirtyChunks.Remove(i) } func (p *Piece) numChunks() int { return p.t.pieceNumChunks(p.index) } func (p *Piece) undirtiedChunkIndices() (ret bitmap.Bitmap) { ret = p.dirtyChunks.Copy() ret.FlipRange(0, p.numChunks()) return } func (p *Piece) incrementPendingWrites() { p.pendingWritesMutex.Lock() p.pendingWrites++ p.pendingWritesMutex.Unlock() } func (p *Piece) decrementPendingWrites() { p.pendingWritesMutex.Lock() if p.pendingWrites == 0 { panic("assertion") } p.pendingWrites-- if p.pendingWrites == 0 { p.noPendingWrites.Broadcast() } p.pendingWritesMutex.Unlock() } func (p *Piece) waitNoPendingWrites() { p.pendingWritesMutex.Lock() for p.pendingWrites != 0 { p.noPendingWrites.Wait() } p.pendingWritesMutex.Unlock() } func (p *Piece) chunkIndexDirty(chunk int) bool { return p.dirtyChunks.Contains(chunk) } func (p *Piece) chunkIndexSpec(chunk int) chunkSpec { return chunkIndexSpec(chunk, p.length(), p.chunkSize()) } func (p *Piece) numDirtyBytes() (ret pp.Integer) { // defer func() { // if ret > p.length() { // panic("too many dirty bytes") // } // }() numRegularDirtyChunks := p.numDirtyChunks() if p.chunkIndexDirty(p.numChunks() - 1) { numRegularDirtyChunks-- ret += p.chunkIndexSpec(p.lastChunkIndex()).Length } ret += pp.Integer(numRegularDirtyChunks) * p.chunkSize() return } func (p *Piece) length() pp.Integer { return p.t.pieceLength(p.index) } func (p *Piece) chunkSize() pp.Integer { return p.t.chunkSize } func (p *Piece) lastChunkIndex() int { return p.numChunks() - 1 } func (p *Piece) bytesLeft() (ret pp.Integer) { if p.t.pieceComplete(p.index) { return 0 } return p.length() - p.numDirtyBytes() } func (p *Piece) VerifyData() { p.t.cl.mu.Lock() defer p.t.cl.mu.Unlock() target := p.numVerifies + 1 if p.hashing { target++ } // log.Printf("target: %d", target) p.t.queuePieceCheck(p.index) for p.numVerifies < target { // log.Printf("got %d verifies", p.numVerifies) p.t.cl.event.Wait() } // log.Print("done") } func (p *Piece) queuedForHash() bool { return p.t.piecesQueuedForHash.Get(p.index) }