storage/file-piece.go

   1 package storage
   2
   3 import (
   4         "github.com/anacrolix/torrent/segments"
   5         "io"
   6         "log"
   7         "os"
   8
   9         "github.com/anacrolix/torrent/metainfo"
  10 )
  11
  12 type filePieceImpl struct {
  13         *fileTorrentImpl
  14         p metainfo.Piece
  15         io.WriterAt
  16         io.ReaderAt
  17 }
  18
  19 var _ PieceImpl = (*filePieceImpl)(nil)
  20
  21 func (me *filePieceImpl) pieceKey() metainfo.PieceKey {
  22         return metainfo.PieceKey{me.infoHash, me.p.Index()}
  23 }
  24
  25 func (fs *filePieceImpl) Completion() Completion {
  26         c, err := fs.completion.Get(fs.pieceKey())
  27         if err != nil {
  28                 log.Printf("error getting piece completion: %s", err)
  29                 c.Ok = false
  30                 return c
  31         }
  32
  33         verified := true
  34         if c.Complete {
  35                 // If it's allegedly complete, check that its constituent files have the necessary length.
  36                 if !fs.segmentLocater.Locate(segments.Extent{
  37                         Start:  fs.p.Offset(),
  38                         Length: fs.p.Length(),
  39                 }, func(i int, extent segments.Extent) bool {
  40                         file := fs.files[i]
  41                         s, err := os.Stat(file.path)
  42                         if err != nil || s.Size() < extent.Start+extent.Length {
  43                                 verified = false
  44                                 return false
  45                         }
  46                         return true
  47                 }) {
  48                         panic("files do not cover piece extent")
  49                 }
  50         }
  51
  52         if !verified {
  53                 // The completion was wrong, fix it.
  54                 c.Complete = false
  55                 fs.completion.Set(fs.pieceKey(), false)
  56         }
  57
  58         return c
  59 }
  60
  61 func (fs *filePieceImpl) MarkComplete() error {
  62         return fs.completion.Set(fs.pieceKey(), true)
  63 }
  64
  65 func (fs *filePieceImpl) MarkNotComplete() error {
  66         return fs.completion.Set(fs.pieceKey(), false)
  67 }