migrate

src/server/torr/reader.go

@@ -0,0 +1,60 @@
+package torr
+
+import (
+	"io"
+
+	"github.com/anacrolix/torrent"
+)
+
+type Reader struct {
+	torrent.Reader
+	offset    int64
+	readahead int64
+	file      *torrent.File
+}
+
+func NewReader(torr *Torrent, file *torrent.File, readahead int64) *Reader {
+	r := new(Reader)
+	r.file = file
+	r.Reader = file.NewReader()
+
+	if readahead <= 0 {
+		readahead = torr.Torrent.Info().PieceLength
+	}
+	r.SetReadahead(readahead)
+	torr.GetCache().AddReader(r)
+	return r
+}
+
+func (r *Reader) Seek(offset int64, whence int) (n int64, err error) {
+	switch whence {
+	case io.SeekStart:
+		r.offset = offset
+	case io.SeekCurrent:
+		r.offset += offset
+	case io.SeekEnd:
+		r.offset = r.file.Length() - offset
+	}
+	n, err = r.Reader.Seek(offset, whence)
+	r.offset = n
+	return
+}
+
+func (r *Reader) Read(p []byte) (n int, err error) {
+	n, err = r.Reader.Read(p)
+	r.offset += int64(n)
+	return
+}
+
+func (r *Reader) SetReadahead(length int64) {
+	r.Reader.SetReadahead(length)
+	r.readahead = length
+}
+
+func (r *Reader) Offset() int64 {
+	return r.offset
+}
+
+func (r *Reader) Readahead() int64 {
+	return r.readahead
+}