9 "github.com/anacrolix/missinggo"
10 "github.com/edsrzf/mmap-go"
12 "github.com/anacrolix/torrent/metainfo"
13 "github.com/anacrolix/torrent/mmap_span"
16 type mmapStorage struct {
21 func NewMMap(baseDir string) ClientImpl {
22 return NewMMapWithCompletion(baseDir, pieceCompletionForDir(baseDir))
25 func NewMMapWithCompletion(baseDir string, completion PieceCompletion) ClientImpl {
32 func (s *mmapStorage) OpenTorrent(info *metainfo.Info, infoHash metainfo.Hash) (t TorrentImpl, err error) {
33 span, err := mMapTorrent(info, s.baseDir)
34 t = &mmapTorrentStorage{
41 func (s *mmapStorage) Close() error {
45 type mmapTorrentStorage struct {
46 span mmap_span.MMapSpan
50 func (ts *mmapTorrentStorage) Piece(p metainfo.Piece) PieceImpl {
51 return mmapStoragePiece{
54 ReaderAt: io.NewSectionReader(ts.span, p.Offset(), p.Length()),
55 WriterAt: missinggo.NewSectionWriter(ts.span, p.Offset(), p.Length()),
59 func (ts *mmapTorrentStorage) Close() error {
61 return ts.span.Close()
64 type mmapStoragePiece struct {
72 func (me mmapStoragePiece) pieceKey() metainfo.PieceKey {
73 return metainfo.PieceKey{me.ih, me.p.Index()}
76 func (sp mmapStoragePiece) GetIsComplete() (ret bool) {
77 ret, _ = sp.pc.Get(sp.pieceKey())
81 func (sp mmapStoragePiece) MarkComplete() error {
82 sp.pc.Set(sp.pieceKey(), true)
86 func (sp mmapStoragePiece) MarkNotComplete() error {
87 sp.pc.Set(sp.pieceKey(), false)
91 func mMapTorrent(md *metainfo.Info, location string) (mms mmap_span.MMapSpan, err error) {
97 for _, miFile := range md.UpvertedFiles() {
98 fileName := filepath.Join(append([]string{location, md.Name}, miFile.Path...)...)
99 err = os.MkdirAll(filepath.Dir(fileName), 0777)
101 err = fmt.Errorf("error creating data directory %q: %s", filepath.Dir(fileName), err)
105 file, err = os.OpenFile(fileName, os.O_CREATE|os.O_RDWR, 0666)
112 fi, err = file.Stat()
116 if fi.Size() < miFile.Length {
117 err = file.Truncate(miFile.Length)
122 if miFile.Length == 0 {
123 // Can't mmap() regions with length 0.
127 mMap, err = mmap.MapRegion(file,
128 int(miFile.Length), // Probably not great on <64 bit systems.
131 err = fmt.Errorf("error mapping file %q, length %d: %s", file.Name(), miFile.Length, err)
134 if int64(len(mMap)) != miFile.Length {
135 panic("mmap has wrong length")