Data.Torrent.Piece

Pieces are used to validate torrent content.

Piece attributes

type PieceIx = Int

Zero-based index of piece in torrent content.

type PieceCount = Int

Number of pieces in torrent or a part of torrent.

type PieceSize = Int

Size of piece in bytes. Should be a power of 2.

NOTE: Have max and min size constrained to wide used semi-standard values. This bounds should be used to make decision about piece size for new torrents.

minPieceSize :: Int

Piece size should not be less than this value.

maxPieceSize :: Int

To prevent transfer degradation piece size should not exceed this value.

defaultPieceSize :: Int64 -> Int

Find the optimal piece size for a given torrent size.

Piece data

data Piece a

Piece payload should be strict or lazy bytestring.

Constructors

Piece

Fields

pieceIndex :: !PieceIx

Zero-based piece index in torrent.

pieceData :: !a

Payload.

Instances

Typeable1 Piece

Eq a => Eq (Piece a)

Read a => Read (Piece a)

Show a => Show (Piece a)

ToJSON a0 => ToJSON (Piece a0)

FromJSON a0 => FromJSON (Piece a0)

NFData (Piece a)

ppPiece :: Piece a -> Doc

Format piece in human readable form. Payload bytes are omitted.

pieceSize :: Piece BL.ByteString -> PieceSize

Get size of piece in bytes.

isPiece :: PieceSize -> Block BL.ByteString -> Bool

Test if a block can be safely turned into a piece.

Piece control

data PieceInfo

Part of torrent file used for torrent content validation.

Constructors

PieceInfo

Fields

piPieceLength :: !PieceSize

Number of bytes in each piece.

piPieceHashes :: !HashArray

Concatenation of all 20-byte SHA1 hash values.

Instances

Eq PieceInfo

Read PieceInfo

Show PieceInfo

Typeable PieceInfo

ToJSON PieceInfo

FromJSON PieceInfo

NFData PieceInfo

BEncode PieceInfo

ppPieceInfo :: PieceInfo -> Doc

Format piece info in human readable form. Hashes are omitted.

pieceCount :: PieceInfo -> PieceCount

Find count of pieces in the torrent. If torrent size is not a multiple of piece size then the count is rounded up.

Lens

pieceLength :: Lens' PieceInfo PieceSize

Number of bytes in each piece.

pieceHashes :: Lens' PieceInfo HashArray

Concatenation of all 20-byte SHA1 hash values.

Validation

pieceHash :: PieceInfo -> PieceIx -> BS.ByteString

Extract validation hash by specified piece index.

checkPieceLazy :: PieceInfo -> Piece BL.ByteString -> Bool

Validate piece with metainfo hash.

Internal

getPieceInfo :: Get PieceInfo

putPieceInfo :: PieceInfo -> BDict -> BDict