// Performs at most one successful read to torrent storage.
func (r *Reader) readOnceAt(b []byte, pos int64, ctxErr *error) (n int, err error) {
if pos >= r.t.length {
err = io.EOF
return
}
for {
avail := r.waitAvailable(pos, int64(len(b)), ctxErr)
if avail == 0 {
if r.t.closed.IsSet() {
err = errors.New("torrent closed")
return
}
if *ctxErr != nil {
err = *ctxErr
return
}
}
b1 := b[:avail]
pi := int(pos / r.t.Info().PieceLength)
ip := r.t.Info().Piece(pi)
po := pos % ip.Length()
missinggo.LimitLen(&b1, ip.Length()-po)
n, err = r.t.readAt(b1, pos)
if n != 0 {
err = nil
return
}
// log.Printf("%s: error reading from torrent storage pos=%d: %s", r.t, pos, err)
r.t.cl.mu.Lock()
r.t.updateAllPieceCompletions()
r.t.updatePiecePriorities()
r.t.cl.mu.Unlock()
}
}
func (me pieceFileTorrentStoragePiece) WriteAt(b []byte, off int64) (n int, err error) {
if me.GetIsComplete() {
err = errors.New("piece completed")
return
}
f, err := me.fs.OpenFile(me.incompletePath(), os.O_WRONLY|os.O_CREATE)
if err != nil {
return
}
defer f.Close()
missinggo.LimitLen(&b, me.p.Length()-off)
return f.WriteAt(b, off)
}
func (s piecePerResourcePiece) ReadAt(b []byte, off int64) (n int, err error) {
missinggo.LimitLen(&b, s.p.Length()-off)
n, err = s.c.ReadAt(b, off)
if err != nil {
n, err = s.i.ReadAt(b, off)
}
off += int64(n)
if off >= s.p.Length() {
err = io.EOF
} else if err == io.EOF {
err = io.ErrUnexpectedEOF
}
return
}
func (me pieceFileTorrentStoragePiece) ReadAt(b []byte, off int64) (n int, err error) {
f, err := me.openFile()
if err != nil {
return
}
defer f.Close()
missinggo.LimitLen(&b, me.p.Length()-off)
n, err = f.ReadAt(b, off)
off += int64(n)
if off >= me.p.Length() {
err = io.EOF
} else if err == io.EOF {
err = io.ErrUnexpectedEOF
}
return
}
func (s piecePerResourcePiece) WriteAt(b []byte, off int64) (n int, err error) {
missinggo.LimitLen(&b, s.p.Length()-off)
return s.i.WriteAt(b, off)
}