+++ /dev/null
-{-
- - Copyright (C) 2015-2016 Ramakrishnan Muthukrishnan <ram@rkrishnan.org>
- -
- - This file is part of FuncTorrent.
- -
- - FuncTorrent is free software; you can redistribute it and/or modify
- - it under the terms of the GNU General Public License as published by
- - the Free Software Foundation; either version 3 of the License, or
- - (at your option) any later version.
- -
- - FuncTorrent is distributed in the hope that it will be useful,
- - but WITHOUT ANY WARRANTY; without even the implied warranty of
- - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- - GNU General Public License for more details.
- -
- - You should have received a copy of the GNU General Public License
- - along with FuncTorrent; if not, see <http://www.gnu.org/licenses/>
- -}
-
-{-# LANGUAGE OverloadedStrings #-}
-
-module FuncTorrent.Peer
- (handlePeerMsgs
- ) where
-
-import Prelude hiding (lookup, concat, replicate, splitAt, take, drop)
-
-import Control.Monad.State
-import Data.ByteString (ByteString, unpack, concat, hGet, hPut, take, drop, empty)
-import Data.Bits
-import Data.Word (Word8)
-import Data.Map ((!), adjust)
-import Network (connectTo, PortID(..))
-import System.IO (Handle, BufferMode(..), hSetBuffering, hClose)
-
-import FuncTorrent.Metainfo (Metainfo(..))
-import FuncTorrent.PeerMsgs (Peer(..), PeerMsg(..), sendMsg, getMsg, genHandshakeMsg)
-import FuncTorrent.Utils (splitNum, verifyHash)
-import FuncTorrent.PieceManager (PieceDlState(..), PieceData(..), PieceMap, pickPiece, updatePieceAvailability)
-import qualified FuncTorrent.FileSystem as FS (MsgChannel, writePieceToDisk)
-
-data PState = PState { handle :: Handle
- , peer :: Peer
- , meChoking :: Bool
- , meInterested :: Bool
- , heChoking :: Bool
- , heInterested :: Bool}
-
-havePiece :: PieceMap -> Integer -> Bool
-havePiece pm index =
- dlstate (pm ! index) == Have
-
-connectToPeer :: Peer -> IO Handle
-connectToPeer (Peer ip port) = do
- h <- connectTo ip (PortNumber (fromIntegral port))
- hSetBuffering h LineBuffering
- return h
-
-doHandshake :: Bool -> Handle -> Peer -> ByteString -> String -> IO ()
-doHandshake True h p infohash peerid = do
- let hs = genHandshakeMsg infohash peerid
- hPut h hs
- putStrLn $ "--> handhake to peer: " ++ show p
- _ <- hGet h (length (unpack hs))
- putStrLn $ "<-- handshake from peer: " ++ show p
- return ()
-doHandshake False h p infohash peerid = do
- let hs = genHandshakeMsg infohash peerid
- putStrLn "waiting for a handshake"
- hsMsg <- hGet h (length (unpack hs))
- putStrLn $ "<-- handshake from peer: " ++ show p
- let rxInfoHash = take 20 $ drop 28 hsMsg
- if rxInfoHash /= infohash
- then do
- putStrLn "infoHashes does not match"
- hClose h
- return ()
- else do
- _ <- hPut h hs
- putStrLn $ "--> handhake to peer: " ++ show p
- return ()
-
-bitfieldToList :: [Word8] -> [Integer]
-bitfieldToList bs = go bs 0
- where go [] _ = []
- go (b:bs') pos =
- let setBits = [pos*8 + toInteger i | i <- [0..8], testBit b i]
- in
- setBits ++ go bs' (pos + 1)
-
--- helper functions to manipulate PeerState
-toPeerState :: Handle
- -> Peer
- -> Bool -- ^ meChoking
- -> Bool -- ^ meInterested
- -> Bool -- ^ heChoking
- -> Bool -- ^ heInterested
- -> PState
-toPeerState h p meCh meIn heCh heIn =
- PState { handle = h
- , peer = p
- , heChoking = heCh
- , heInterested = heIn
- , meChoking = meCh
- , meInterested = meIn }
-
-handlePeerMsgs :: Peer -> String -> Metainfo -> PieceMap -> Bool -> FS.MsgChannel -> IO ()
-handlePeerMsgs p peerId m pieceMap isClient c = do
- h <- connectToPeer p
- doHandshake isClient h p (infoHash m) peerId
- let pstate = toPeerState h p False False True True
- _ <- runStateT (msgLoop pieceMap c) pstate
- return ()
-
-msgLoop :: PieceMap -> FS.MsgChannel -> StateT PState IO ()
-msgLoop pieceStatus msgchannel = do
- h <- gets handle
- 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 msgchannel
- 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"
- else do
- liftIO $ putStrLn $ "Write piece: " ++ show workPiece
- liftIO $ FS.writePieceToDisk msgchannel workPiece pBS
- msgLoop (adjust (\pieceData -> pieceData { dlstate = Have }) workPiece pieceStatus) msgchannel
- _ -> 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 msgchannel
- 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' msgchannel
- UnChokeMsg -> do
- modify (\st' -> st' {heChoking = False })
- msgLoop pieceStatus msgchannel
- ChokeMsg -> do
- modify (\st' -> st' {heChoking = True })
- msgLoop pieceStatus msgchannel
- InterestedMsg -> do
- modify (\st' -> st' {heInterested = True})
- msgLoop pieceStatus msgchannel
- NotInterestedMsg -> do
- modify (\st' -> st' {heInterested = False})
- msgLoop pieceStatus msgchannel
- CancelMsg {} -> -- check if valid index, begin, length
- msgLoop pieceStatus msgchannel
- PortMsg _ ->
- msgLoop pieceStatus msgchannel
- HaveMsg idx -> do
- p <- gets peer
- let pieceStatus' = updatePieceAvailability pieceStatus p [idx]
- msgLoop pieceStatus' msgchannel
- _ -> do
- liftIO $ putStrLn ".. not doing anything with the msg"
- msgLoop pieceStatus msgchannel
- -- No need to handle PieceMsg and RequestMsg here.
-
-
-downloadPiece :: Handle -> Integer -> Integer -> IO ByteString
-downloadPiece h index pieceLength = do
- let chunks = splitNum pieceLength 16384
- 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: " ++ show msg
- return empty)
-
projects / functorrent.git / blobdiff