package torrent import ( "github.com/RoaringBitmap/roaring" "github.com/anacrolix/missinggo/v2/bitmap" "github.com/anacrolix/torrent/metainfo" ) // Provides access to regions of torrent data that correspond to its files. type File struct { t *Torrent path string offset int64 length int64 fi metainfo.FileInfo displayPath string prio piecePriority } func (f *File) Torrent() *Torrent { return f.t } // Data for this file begins this many bytes into the Torrent. func (f *File) Offset() int64 { return f.offset } // The FileInfo from the metainfo.Info to which this file corresponds. func (f File) FileInfo() metainfo.FileInfo { return f.fi } // The file's path components joined by '/'. func (f File) Path() string { return f.path } // The file's length in bytes. func (f *File) Length() int64 { return f.length } // Number of bytes of the entire file we have completed. This is the sum of // completed pieces, and dirtied chunks of incomplete pieces. func (f *File) BytesCompleted() int64 { f.t.cl.rLock() defer f.t.cl.rUnlock() return f.bytesCompleted() } func (f *File) bytesCompleted() int64 { return f.length - f.bytesLeft() } func fileBytesLeft( torrentUsualPieceSize int64, fileFirstPieceIndex int, fileEndPieceIndex int, fileTorrentOffset int64, fileLength int64, torrentCompletedPieces *roaring.Bitmap, ) (left int64) { numPiecesSpanned := fileEndPieceIndex - fileFirstPieceIndex switch numPiecesSpanned { case 0: case 1: if !torrentCompletedPieces.Contains(bitmap.BitIndex(fileFirstPieceIndex)) { left += fileLength } default: if !torrentCompletedPieces.Contains(bitmap.BitIndex(fileFirstPieceIndex)) { left += torrentUsualPieceSize - (fileTorrentOffset % torrentUsualPieceSize) } if !torrentCompletedPieces.Contains(bitmap.BitIndex(fileEndPieceIndex - 1)) { left += fileTorrentOffset + fileLength - int64(fileEndPieceIndex-1)*torrentUsualPieceSize } completedMiddlePieces := torrentCompletedPieces.Clone() completedMiddlePieces.RemoveRange(0, bitmap.BitRange(fileFirstPieceIndex+1)) completedMiddlePieces.RemoveRange(bitmap.BitRange(fileEndPieceIndex-1), bitmap.ToEnd) left += int64(numPiecesSpanned-2-pieceIndex(completedMiddlePieces.GetCardinality())) * torrentUsualPieceSize } return } func (f *File) bytesLeft() (left int64) { return fileBytesLeft(int64(f.t.usualPieceSize()), f.firstPieceIndex(), f.endPieceIndex(), f.offset, f.length, &f.t._completedPieces) } // The relative file path for a multi-file torrent, and the torrent name for a // single-file torrent. Dir separators are '/'. func (f *File) DisplayPath() string { return f.displayPath } // The download status of a piece that comprises part of a File. type FilePieceState struct { Bytes int64 // Bytes within the piece that are part of this File. PieceState } // Returns the state of pieces in this file. func (f *File) State() (ret []FilePieceState) { f.t.cl.rLock() defer f.t.cl.rUnlock() pieceSize := int64(f.t.usualPieceSize()) off := f.offset % pieceSize remaining := f.length for i := pieceIndex(f.offset / pieceSize); ; i++ { if remaining == 0 { break } len1 := pieceSize - off if len1 > remaining { len1 = remaining } ps := f.t.pieceState(i) ret = append(ret, FilePieceState{len1, ps}) off = 0 remaining -= len1 } return } // Requests that all pieces containing data in the file be downloaded. func (f *File) Download() { f.SetPriority(PiecePriorityNormal) } func byteRegionExclusivePieces(off, size, pieceSize int64) (begin, end int) { begin = int((off + pieceSize - 1) / pieceSize) end = int((off + size) / pieceSize) return } // Deprecated: Use File.SetPriority. func (f *File) Cancel() { f.SetPriority(PiecePriorityNone) } func (f *File) NewReader() Reader { tr := reader{ mu: f.t.cl.locker(), t: f.t, readahead: 5 * 1024 * 1024, offset: f.Offset(), length: f.Length(), } f.t.addReader(&tr) return &tr } // Sets the minimum priority for pieces in the File. func (f *File) SetPriority(prio piecePriority) { f.t.cl.lock() defer f.t.cl.unlock() if prio == f.prio { return } f.prio = prio f.t.updatePiecePriorities(f.firstPieceIndex(), f.endPieceIndex()) } // Returns the priority per File.SetPriority. func (f *File) Priority() piecePriority { f.t.cl.lock() defer f.t.cl.unlock() return f.prio } // Returns the index of the first piece containing data for the file. func (f *File) firstPieceIndex() pieceIndex { if f.t.usualPieceSize() == 0 { return 0 } return pieceIndex(f.offset / int64(f.t.usualPieceSize())) } // Returns the index of the piece after the last one containing data for the file. func (f *File) endPieceIndex() pieceIndex { if f.t.usualPieceSize() == 0 { return 0 } return pieceIndex((f.offset + f.length + int64(f.t.usualPieceSize()) - 1) / int64(f.t.usualPieceSize())) }