torrent/file.go

99 lines
2.0 KiB
Go

package torrent
import (
"strings"
"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
}
func (f *File) Torrent() Torrent {
return f.t
}
// Data for this file begins this far into the torrent.
func (f *File) Offset() int64 {
return f.offset
}
func (f File) FileInfo() metainfo.FileInfo {
return f.fi
}
func (f File) Path() string {
return f.path
}
func (f *File) Length() int64 {
return f.length
}
// The relative file path for a multi-file torrent, and the torrent name for a
// single-file torrent.
func (f *File) DisplayPath() string {
fip := f.FileInfo().Path
if len(fip) == 0 {
return f.t.Info().Name
}
return strings.Join(fip, "/")
}
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) {
pieceSize := int64(f.t.torrent.usualPieceSize())
off := f.offset % pieceSize
remaining := f.length
for i := int(f.offset / pieceSize); ; i++ {
if remaining == 0 {
break
}
len1 := pieceSize - off
if len1 > remaining {
len1 = remaining
}
f.t.cl.mu.RLock()
ps := f.t.torrent.pieceState(i)
f.t.cl.mu.RUnlock()
ret = append(ret, FilePieceState{len1, ps})
off = 0
remaining -= len1
}
return
}
func (f *File) Download() {
f.t.DownloadPieces(f.t.torrent.byteRegionPieces(f.offset, f.length))
}
func (f *File) PrioritizeRegion(off, len int64) {
f.t.DownloadPieces(f.t.torrent.byteRegionPieces(f.offset+off, len))
}
func byteRegionExclusivePieces(off, size, pieceSize int64) (begin, end int) {
begin = int((off + pieceSize - 1) / pieceSize)
end = int((off + size) / pieceSize)
return
}
func (f *File) exclusivePieces() (begin, end int) {
return byteRegionExclusivePieces(f.offset, f.length, int64(f.t.torrent.usualPieceSize()))
}
func (f *File) Cancel() {
f.t.CancelPieces(f.exclusivePieces())
}