From: Ramakrishnan Muthukrishnan Date: Fri, 24 Jul 2015 12:46:27 +0000 (+0530) Subject: split download of a piece into chunks of 16384 bytes X-Git-Url: https://git.rkrishnan.org/%5B/%5D%20/file/URI:LIT:krugkidfnzsc4/@@named=/frontends/CLI.txt?a=commitdiff_plain;h=045dd2b47a76006bfa610cc26f5aceb63877ba02;p=functorrent.git split download of a piece into chunks of 16384 bytes The pieceLenth can often be quite big, so we need to split the piece into smaller blocks of size 16384 bytes. Why 16384? Just an arbit number. It seem to work okay. --- diff --git a/src/FuncTorrent/Peer.hs b/src/FuncTorrent/Peer.hs index 6b84666..ba7f7a9 100644 --- a/src/FuncTorrent/Peer.hs +++ b/src/FuncTorrent/Peer.hs @@ -14,14 +14,14 @@ import Network (connectTo, PortID(..)) import Data.Binary (Binary(..), decode, encode) import Data.Binary.Put (putWord32be, putWord16be, putWord8) import Data.Binary.Get (getWord32be, getWord16be, getWord8, runGet) -import Control.Monad (replicateM, liftM, forever) +import Control.Monad (replicateM, liftM, forM, forever) import Control.Applicative ((<$>), liftA3) import Data.Bits import Data.Word (Word8) -import Data.Map (Map(..), fromList, toList, (!), mapWithKey) +import Data.Map (Map(..), fromList, toList, (!), mapWithKey, adjust) import FuncTorrent.Metainfo (Info(..), Metainfo(..)) -import FuncTorrent.Utils (splitN) +import FuncTorrent.Utils (splitN, splitNum) type ID = String type IP = String @@ -72,13 +72,13 @@ data PeerMsg = KeepAliveMsg -- Make the initial Piece map, with the assumption that no peer has the -- piece and that every piece is pending download. -mkPieceMap :: Integer -> ByteString -> Integer -> PieceMap -mkPieceMap numPieces pieceHash pLen = fromList kvs +mkPieceMap :: Integer -> ByteString -> [Integer] -> PieceMap +mkPieceMap numPieces pieceHash pLengths = fromList kvs where kvs = [(i, PieceData { peers = [] , state = Pending , hash = h , len = pLen }) - | (i, h) <- zip [0..numPieces] hashes] + | (i, h, pLen) <- zip3 [0..numPieces] hashes pLengths] hashes = splitN (fromIntegral numPieces) pieceHash havePiece :: PieceMap -> Integer -> Bool @@ -188,8 +188,6 @@ bitfieldToList bs = go bs 0 in setBits ++ go bs' (pos + 1) --- downloadPiece :: Integer -> Handle -> IO () - createDummyFile :: FilePath -> Int -> IO () createDummyFile path size = writeFile path (BC.replicate size '\0') @@ -213,11 +211,12 @@ msgLoop state pieceStatus | meInterested state == False && Nothing -> putStrLn "Nothing to download" Just workPiece -> do let pLen = len (pieceStatus ! workPiece) - sendMsg (handle state) (RequestMsg workPiece 0 pLen) - putStrLn $ "--> RequestMsg for Piece " ++ (show workPiece) ++ "to peer: " ++ show (peer state) - msg <- getMsg (handle state) - putStrLn $ "<-- " ++ show msg ++ "from peer: " ++ show (peer state) - -- msgLoop state pieceStatus + pBS <- downloadPiece (handle state) workPiece pLen + -- sendMsg (handle state) (RequestMsg workPiece 0 pLen) + -- putStrLn $ "--> RequestMsg for Piece " ++ (show workPiece) ++ "to peer: " ++ show (peer state) ++ " of length: " ++ show pLen + -- msg <- getMsg (handle state) + -- putStrLn $ "<-- " ++ show msg ++ "from peer: " ++ show (peer state) + msgLoop state (adjust (\pieceData -> pieceData { state = Have }) workPiece pieceStatus) | otherwise = do msg <- getMsg (handle state) putStrLn $ "<-- " ++ show msg ++ "from peer: " ++ show (peer state) @@ -268,7 +267,16 @@ handlePeerMsgs p m peerId logFn = do , meChoking = True } pieceHash = pieces (info m) numPieces = (toInteger . (`quot` 20) . BC.length) pieceHash - pLen = pieceLength (info m) :: Integer - pieceStatus = mkPieceMap numPieces pieceHash pLen + pLen = pieceLength (info m) + fileLen = lengthInBytes (info m) + pieceStatus = mkPieceMap numPieces pieceHash (splitNum fileLen pLen) msgLoop state pieceStatus +downloadPiece :: Handle -> Integer -> Integer -> IO [PeerMsg] +downloadPiece h index pieceLength = do + let chunks = splitNum pieceLength 16384 + forM (zip [0..] chunks) (\(i, pLen) -> do + sendMsg h (RequestMsg index (i*pLen) pLen) + putStrLn $ "--> " ++ "RequestMsg for Piece " ++ (show index) ++ ", part: " ++ show i ++ " of length: " ++ show pLen + -- putStrLn $ "--> RequestMsg for Piece " ++ (show workPiece) ++ "to peer: " ++ show (peer state) ++ " of length: " ++ show pLen + getMsg h) diff --git a/src/FuncTorrent/Utils.hs b/src/FuncTorrent/Utils.hs index e5a4a55..cf6c284 100644 --- a/src/FuncTorrent/Utils.hs +++ b/src/FuncTorrent/Utils.hs @@ -5,3 +5,8 @@ import qualified Data.ByteString.Char8 as BC splitN :: Int -> BC.ByteString -> [BC.ByteString] splitN n bs | BC.null bs = [] | otherwise = BC.take n bs : splitN n (BC.drop n bs) + +splitNum :: Integer -> Integer -> [Integer] +splitNum n d | n == 0 = [] + | n < d = [n] + | otherwise = d : splitNum (n - d) d