{-# LANGUAGE OverloadedStrings #-}
module FuncTorrent.Peer
(Peer(..),
- handlePeerMsgs
+ handlePeerMsgs,
+ bytesDownloaded
) where
-import Prelude hiding (lookup, concat, replicate, splitAt, take)
+import Prelude hiding (lookup, concat, replicate, splitAt, take, filter)
import System.IO (Handle, BufferMode(..), hSetBuffering)
import Data.ByteString (ByteString, unpack, concat, hGet, hPut, take, empty)
import Control.Monad.State
import Data.Bits
import Data.Word (Word8)
-import Data.Map (Map, fromList, toList, (!), mapWithKey, adjust)
+import Data.Map (Map, fromList, toList, (!), mapWithKey, adjust, filter)
import qualified Crypto.Hash.SHA1 as SHA1 (hash)
+import Safe (headMay)
import FuncTorrent.Metainfo (Info(..), Metainfo(..))
import FuncTorrent.Utils (splitN, splitNum)
type PeerState = State PState
data PieceDlState = Pending
- | InProgress
+ | Downloading
| Have
deriving (Show, Eq)
--- todo - map with index to a new data structure (peers who have that piece amd state)
+-- todo - map with index to a new data structure (peers who have that piece and state)
data PieceData = PieceData { peers :: [Peer] -- ^ list of peers who have this piece
, dlstate :: PieceDlState -- ^ state of the piece from download perspective.
, hash :: ByteString -- ^ piece hash
, meChoking = meCh
, meInterested = meIn }
--- -- recvMsg :: Peer -> Handle -> Msg
--- msgLoop :: PeerState -> PieceMap -> FilePath -> IO ()
--- msgLoop pState@(PeerState { meInterested = False, heChoking = True }) pieceStatus file = do
--- -- if me NOT Interested and she is Choking, tell her that
--- -- I am interested.
--- let h = handle pState
--- sendMsg h InterestedMsg
--- putStrLn $ "--> InterestedMsg to peer: " ++ show (peer pState)
--- msgLoop (pState { meInterested = True }) pieceStatus file
--- msgLoop pState@(PeerState { meInterested = True, heChoking = False }) pieceStatus file =
--- -- if me Interested and she not Choking, send her a request
--- -- for a piece.
--- case pickPiece pieceStatus of
--- Nothing -> putStrLn "Nothing to download"
--- Just workPiece -> do
--- let pLen = len (pieceStatus ! workPiece)
--- putStrLn $ "piece length = " ++ show pLen
--- pBS <- downloadPiece (handle pState) workPiece pLen
--- if not $ verifyHash pBS (hash (pieceStatus ! workPiece))
--- then
--- putStrLn $ "Hash mismatch: " ++ show (hash (pieceStatus ! workPiece)) ++ " vs " ++ show (take 20 (SHA1.hash pBS))
--- else do
--- let fileOffset = if workPiece == 0 then 0 else workPiece * len (pieceStatus ! (workPiece - 1))
--- putStrLn $ "Write into file at offset: " ++ show fileOffset
--- writeFileAtOffset file fileOffset pBS
--- msgLoop pState (adjust (\pieceData -> pieceData { state = Have }) workPiece pieceStatus) file
--- msgLoop pState pieceStatus file = do
--- msg <- getMsg (handle pState)
--- putStrLn $ "<-- " ++ show msg ++ "from peer: " ++ show (peer pState)
--- case msg of
--- KeepAliveMsg -> do
--- sendMsg (handle pState) KeepAliveMsg
--- putStrLn $ "--> " ++ "KeepAliveMsg to peer: " ++ show (peer pState)
--- msgLoop pState pieceStatus file
--- BitFieldMsg bss -> do
--- let pieceList = bitfieldToList (unpack bss)
--- pieceStatus' = updatePieceAvailability pieceStatus (peer pState) pieceList
--- putStrLn $ show (length pieceList) ++ " Pieces"
--- -- for each pieceIndex in pieceList, make an entry in the pieceStatus
--- -- map with pieceIndex as the key and modify the value to add the peer.
--- -- download each of the piece in order
--- msgLoop pState pieceStatus' file
--- UnChokeMsg ->
--- msgLoop (pState { heChoking = False }) pieceStatus file
--- _ ->
--- msgLoop pState pieceStatus file
-
-- simple algorithm to pick piece.
-- pick the first piece from 0 that is not downloaded yet.
pickPiece :: PieceMap -> Maybe Integer
-pickPiece m =
- let pieceList = toList m
- allPending = filter (\(_, v) -> dlstate v == Pending) pieceList
- in
- case allPending of
- [] -> Nothing
- ((i, _):_) -> Just i
+pickPiece =
+ (fst `liftM`) . headMay . toList . filter (\v -> dlstate v == Pending)
+
+bytesDownloaded :: PieceMap -> Integer
+bytesDownloaded =
+ sum . (map (len . snd)) . toList . filter (\v -> dlstate v == Have)
updatePieceAvailability :: PieceMap -> Peer -> [Integer] -> PieceMap
updatePieceAvailability pieceStatus p pieceList =
then (pd { peers = p : peers pd })
else pd) pieceStatus
-handlePeerMsgs :: Peer -> Metainfo -> String -> IO ()
-handlePeerMsgs p m peerId = do
+handlePeerMsgs :: Peer -> String -> Metainfo -> IO ()
+handlePeerMsgs p peerId m = do
h <- connectToPeer p
doHandshake h p (infoHash m) peerId
- let pstate = toPeerState h p False True False True
+ let pstate = toPeerState h p False False True True
pieceHash = pieces (info m)
numPieces = (toInteger . (`quot` 20) . BC.length) pieceHash
pLen = pieceLength (info m)
fileName = name (info m)
pieceStatus = mkPieceMap numPieces pieceHash (splitNum fileLen pLen)
createDummyFile fileName (fromIntegral fileLen)
- (r, _) <- runStateT (msgLoop pieceStatus fileName) pstate
+ _ <- runStateT (msgLoop pieceStatus fileName) pstate
return ()
msgLoop :: PieceMap -> FilePath -> StateT PState IO ()
msgLoop pieceStatus file = do
h <- gets handle
- msg <- liftIO $ getMsg h
- gets peer >>= (\p -> liftIO $ putStrLn $ "<-- " ++ show msg ++ "from peer: " ++ show p)
- case msg of
- KeepAliveMsg -> do
- liftIO $ sendMsg h KeepAliveMsg
- gets peer >>= (\p -> liftIO $ putStrLn $ "--> " ++ "KeepAliveMsg to peer: " ++ show p)
+ st <- get
+ case st of
+ PState { meInterested = False, heChoking = True } -> do
+ liftIO $ sendMsg h InterestedMsg
+ gets peer >>= (\p -> liftIO $ putStrLn $ "--> InterestedMsg to peer: " ++ show p)
+ modify (\st -> st { meInterested = True })
msgLoop pieceStatus file
+ PState { meInterested = True, heChoking = False } ->
+ case pickPiece pieceStatus of
+ Nothing -> liftIO $ putStrLn "Nothing to download"
+ Just workPiece -> do
+ let pLen = len (pieceStatus ! workPiece)
+ liftIO $ putStrLn $ "piece length = " ++ show pLen
+ pBS <- liftIO $ downloadPiece h workPiece pLen
+ if not $ verifyHash pBS (hash (pieceStatus ! workPiece))
+ then
+ liftIO $ putStrLn $ "Hash mismatch: " ++ show (hash (pieceStatus ! workPiece)) ++ " vs " ++ show (take 20 (SHA1.hash pBS))
+ else do
+ let fileOffset = if workPiece == 0 then 0 else workPiece * len (pieceStatus ! (workPiece - 1))
+ liftIO $ putStrLn $ "Write into file at offset: " ++ show fileOffset
+ liftIO $ writeFileAtOffset file fileOffset pBS
+ msgLoop (adjust (\pieceData -> pieceData { dlstate = Have }) workPiece pieceStatus) file
+ _ -> do
+ msg <- liftIO $ getMsg h
+ gets peer >>= (\p -> liftIO $ putStrLn $ "<-- " ++ show msg ++ "from peer: " ++ show p)
+ case msg of
+ KeepAliveMsg -> do
+ liftIO $ sendMsg h KeepAliveMsg
+ gets peer >>= (\p -> liftIO $ putStrLn $ "--> " ++ "KeepAliveMsg to peer: " ++ show p)
+ msgLoop pieceStatus file
+ BitFieldMsg bss -> do
+ p <- gets peer
+ let pieceList = bitfieldToList (unpack bss)
+ pieceStatus' = updatePieceAvailability pieceStatus p pieceList
+ liftIO $ putStrLn $ show (length pieceList) ++ " Pieces"
+ -- for each pieceIndex in pieceList, make an entry in the pieceStatus
+ -- map with pieceIndex as the key and modify the value to add the peer.
+ -- download each of the piece in order
+ msgLoop pieceStatus' file
+ UnChokeMsg -> do
+ modify (\st -> st {heChoking = False })
+ msgLoop pieceStatus file
+
downloadPiece :: Handle -> Integer -> Integer -> IO ByteString
downloadPiece h index pieceLength = do
let chunks = splitNum pieceLength 16384
- liftM concat $ 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
- msg <- getMsg h
- case msg of
- PieceMsg index begin block -> do
- putStrLn $ " <-- PieceMsg for Piece: "
- ++ show index
- ++ ", offset: "
- ++ show begin
- return block
- _ -> do
- putStrLn "ignoring irrelevant msg"
- return empty)
+ concat `liftM` 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
+ msg <- getMsg h
+ case msg of
+ PieceMsg index begin block -> do
+ putStrLn $ " <-- PieceMsg for Piece: "
+ ++ show index
+ ++ ", offset: "
+ ++ show begin
+ return block
+ _ -> do
+ putStrLn "ignoring irrelevant msg"
+ return empty)
verifyHash :: ByteString -> ByteString -> Bool
verifyHash bs pieceHash =
projects / functorrent.git / blobdiff