path: root/examples/dhtd.hs

{-# LANGUAGE CPP                       #-}
{-# LANGUAGE ExistentialQuantification #-}
{-# LANGUAGE FlexibleContexts          #-}
{-# LANGUAGE FlexibleInstances         #-}
{-# LANGUAGE LambdaCase                #-}
{-# LANGUAGE MultiParamTypeClasses     #-}
{-# LANGUAGE NamedFieldPuns            #-}
{-# LANGUAGE NondecreasingIndentation  #-}
{-# LANGUAGE OverloadedStrings         #-}
{-# LANGUAGE PartialTypeSignatures     #-}
{-# LANGUAGE RankNTypes                #-}
{-# LANGUAGE RecordWildCards           #-}
{-# LANGUAGE ScopedTypeVariables       #-}
{-# LANGUAGE TupleSections             #-}
{-# LANGUAGE TypeFamilies              #-}

import Control.Arrow
import Control.Concurrent.STM
import Control.DeepSeq
import Control.Exception
import Control.Monad
import Data.Char
import Data.Hashable
import Data.List
import qualified Data.Map as Map
import Data.Maybe
import qualified Data.Set as Set
import Data.Time.Clock
import GHC.Conc (threadStatus,ThreadStatus(..))
import GHC.Stats
import Network.Socket
import System.Environment
import System.IO
import System.Mem
import System.Posix.Process
import Text.PrettyPrint.HughesPJClass
import Text.Printf
import Text.Read
#ifdef THREAD_DEBUG
import Control.Concurrent.Lifted.Instrument
#else
import Control.Concurrent.Lifted
import GHC.Conc                  (labelThread)
#endif

import Network.Address hiding (NodeId, NodeInfo(..))
import Network.BitTorrent.DHT.Search
import Network.QueryResponse
import Network.StreamServer
import Kademlia
import qualified Mainline
import qualified Tox
import Network.DHT.Routing as R
import Data.Aeson as J (ToJSON, FromJSON)
import qualified Data.Aeson as J
import qualified Data.ByteString.Lazy as L
import Tasks
import System.IO.Error
import qualified Data.Serialize as S
import Network.BitTorrent.DHT.ContactInfo as Peers
import qualified Data.MinMaxPSQ as MM

showReport :: [(String,String)] -> String
showReport kvs = showColumns $ map (\(x,y)->[x,y]) kvs

showColumns rows = do
    let cols = transpose rows
        ws = map (maximum . map (succ . length)) cols
    fs <- rows
    _ <- take 1 fs -- Guard against empty rows so that 'last' is safe.
    "  " ++ concat (zipWith (printf "%-*s") (init ws) (init fs)) ++ last fs ++ "\n"


marshalForClient :: String -> String
marshalForClient s = show (length s) ++ ":" ++ s

-- | Writes a message and signals ready for next command.
hPutClient :: Handle -> String -> IO ()
hPutClient h s = hPutStr h ('.' : marshalForClient s)

-- | Writes message, but signals there is more to come.
hPutClientChunk :: Handle -> String -> IO ()
hPutClientChunk h s = hPutStr h (' ' : marshalForClient s)

data DHTQuery nid ni = forall addr r tok. Ord addr => DHTQuery
    { qsearch  :: Search nid addr tok ni r
    , qhandler :: ni -> nid -> IO ([ni], [r], tok)
    , qshowR   :: r -> String
    , qshowTok :: tok -> Maybe String
    }

data DHTSearch nid ni = forall addr tok r. DHTSearch
    { searchThread     :: ThreadId
    , searchState      :: SearchState nid addr tok ni r
    , searchShowTok    :: tok -> Maybe String
    , searchResults    :: TVar (Set.Set String)
    }

data DHT = forall nid ni. ( Show     ni
                          , Read     ni
                          , ToJSON   ni
                          , FromJSON ni
                          , Ord      ni
                          , Hashable ni
                          , Show     nid
                          , Ord      nid
                          , Hashable nid
                          ) =>
    DHT
    { dhtBuckets  :: TVar (BucketList ni)
    , dhtPing     :: ni -> IO Bool
    , dhtQuery    :: Map.Map String (DHTQuery nid ni)
    , dhtParseId  :: String -> Either String nid
    , dhtSearches :: TVar (Map.Map (String,nid) (DHTSearch nid ni))
    }

nodesFileName :: String -> String
nodesFileName netname = netname ++ "-nodes.json"

saveNodes :: String -> DHT -> IO ()
saveNodes netname DHT{dhtBuckets} = do
    bkts <- atomically $ readTVar dhtBuckets
    let ns = map fst $ concat $ R.toList bkts
        bs = J.encode ns
        fname = nodesFileName netname
    L.writeFile fname bs

loadNodes :: FromJSON ni => String -> IO [ni]
loadNodes netname = do
    let fname = nodesFileName netname
    attempt <- tryIOError $ do
        J.decode <$> L.readFile fname
         >>= maybe (ioError $ userError "Nothing") return
    either (const $ return []) return attempt

pingNodes :: String -> DHT -> IO Bool
pingNodes netname DHT{dhtPing} = do
    let fname = nodesFileName netname
    attempt <- tryIOError $ do
        J.decode <$> L.readFile fname
         >>= maybe (ioError $ userError "Nothing") return
    case attempt of
        Left _   -> return False
        Right ns -> do fork $ do
                         myThreadId >>= flip labelThread ("pinging."++fname)
                         putStrLn $ "Forked "++show fname
                         withTaskGroup ("withTaskGroup."++fname) 10 $ \g -> do
                           mapM_ (\n -> forkTask g (show n) $ void $ dhtPing n)
                                 (ns `asTypeOf` [])
                         putStrLn $ "Load finished "++show fname
                       return True



reportTable :: Show ni => BucketList ni -> [(String,String)]
reportTable bkts = map (show *** show . fst)
                 $ concat
                 $ zipWith map (map (,) [0::Int ..])
                 $ R.toList
                 $ bkts

reportResult ::
    String
    -> (r -> String)
    -> (tok -> Maybe String)
    -> (ni -> String)
    -> Handle
    -> Either String ([ni],[r],tok)
    -> IO ()
reportResult meth showR showTok showN h (Left e)            = hPutClient h e
reportResult meth showR showTok showN h (Right (ns,rs,tok)) = do
    hPutClient h $ showReport report
 where
    report = intercalate [("","")] [ tok_r , node_r , result_r ]

    tok_r = maybe [] (pure . ("token:",)) $ showTok tok

    node_r = map ( ("n",) . showN ) ns

    result_r | (meth=="node") = []
             | otherwise      = map ( (take 1 meth,) . showR ) rs

-- example:
-- * 10 peer 141d6c6ee2810f46d28bbe8373d4f454a4122535
-- - 1  peer 141d6c6ee2810f46d28bbe8373d4f454a4122535
--   22 node 141d6c6ee2810f46d28bbe8373d4f454a4122535
--
-- key: '*' in progress
--      '-' stopped
--      ' ' finished
showSearches :: ( Show nid
                , Ord nid
                , Hashable nid
                , Ord ni
                , Hashable ni
                ) => Map.Map (String,nid) (DHTSearch nid ni) -> IO String
showSearches searches = do
    tups <- forM (Map.toList searches) $ \((meth,nid),DHTSearch{..}) -> do
        (is'fin, cnt) <- atomically $
                (,) <$> searchIsFinished searchState
                    <*> (Set.size <$> readTVar searchResults)
        tstat <- threadStatus searchThread
        let stat = case tstat of
                _ | is'fin     -> ' '
                ThreadFinished -> '-'
                ThreadDied     -> '-'
                _              -> '*'
        return (stat,show cnt,meth,show nid)
    let cnt'width = maximum $ map (\(_,cnt,_,_)->length cnt) tups
        mth'width = maximum $ map (\(_,_,mth,_)->length mth) tups
    return $ do -- List monad.
        (stat,cnt,meth,nid) <- tups
        printf "  %c %-*s %-*s %s\n" stat cnt'width cnt mth'width meth nid

forkSearch ::
    ( Ord nid
    , Hashable nid
    , Ord ni
    , Hashable ni
    , Show nid
    ) =>
    String
    -> nid
    -> DHTQuery nid ni
    -> TVar (Map.Map (String,nid) (DHTSearch nid ni))
    -> TVar (BucketList ni)
    -> ThreadId
    -> TVar (Maybe (IO ()))
    -> STM ()
forkSearch method nid DHTQuery{qsearch,qshowTok,qshowR} dhtSearches dhtBuckets  tid kvar = do
    ns <- R.kclosest (searchSpace qsearch) searchK nid <$> readTVar dhtBuckets
    st <- newSearch qsearch nid ns
    results <- newTVar Set.empty
    let storeResult r = modifyTVar' results (Set.insert (qshowR r))
                        >> return True
        new = DHTSearch
            { searchThread  = tid
            , searchState   = st
            , searchShowTok = qshowTok
            , searchResults = results
            }
    modifyTVar' dhtSearches $ Map.insert (method,nid) new
    writeTVar kvar $ Just $ searchLoop qsearch nid storeResult st

reportSearchResults meth h DHTSearch{searchShowTok,searchState,searchResults} = do
    (ns,rs) <- atomically $ do
        mm <- readTVar $ searchInformant searchState
        rset <- readTVar searchResults
        let ns = map (\(MM.Binding ni tok _) -> (ni,tok))
                     $ MM.toList mm
            rs = Set.toList rset
        return (ns,rs)
    let n'width       = succ $ maximum $ map (length . show . fst) ns
        showN (n,tok) = take n'width (show n ++ repeat ' ') ++ (fromMaybe "" $ searchShowTok tok)
        ns'           = map showN ns
    reportResult meth id (const Nothing) id h (Right (ns',rs,()))

data Session = Session
    { netname           :: String
    , dhts              :: Map.Map String DHT
    , externalAddresses :: IO [SockAddr]
    , swarms            :: Mainline.SwarmsDatabase
    , signalQuit        :: MVar ()
    }

clientSession s@Session{..} sock cnum h = do
    line <- map toLower . dropWhile isSpace <$> hGetLine h
    let (c,args) = second (dropWhile isSpace) $ break isSpace line
        cmd0 :: IO () -> IO ()
        cmd0 action = action >> clientSession s sock cnum h
        switchNetwork dest = do hPutClient h ("Network: "++dest)
                                clientSession s{netname=dest} sock cnum h
    case (c,args) of
        ("stop", _) -> do hPutClient h "Terminating DHT Daemon."
                          hClose h
                          putMVar signalQuit ()

        ("quit", _) -> hPutClient h "" >> hClose h

        ("pid", _) -> cmd0 $ do
                    pid <- getProcessID
                    hPutClient h (show pid)
        ("external-ip", _) -> cmd0 $ do
                    unlines . map (either show show . either4or6) <$> externalAddresses
                        >>= hPutClient h
#ifdef THREAD_DEBUG
        ("threads", _) -> cmd0 $ do
                    ts <- threadsInformation
                    tm <- getCurrentTime
                    r <- forM ts $ \(tid,PerThread{..}) -> do
                        stat <- threadStatus tid
                        let showStat (ThreadBlocked reason) = show reason
                            showStat stat                   = show stat
                        return [show lbl,show (diffUTCTime tm startTime),showStat stat]
                    hPutClient h $ showColumns r
#endif
        ("mem", s) -> cmd0 $ do
                    case s of
                        "gc" -> do hPutClient h "Performing garbage collection..."
                                   performMajorGC
                        "" -> do
                            is_enabled <- getGCStatsEnabled
                            if is_enabled
                             then do
                                GCStats{..} <- getGCStats
                                let r = [ ("bytesAllocated", show bytesAllocated)
                                        , ("numGcs", show numGcs)
                                        , ("maxBytesUsed", show maxBytesUsed)
                                        , ("numByteUsageSamples", show numByteUsageSamples)
                                        , ("cumulativeBytesUsed", show cumulativeBytesUsed)
                                        , ("bytesCopied", show bytesCopied)
                                        , ("currentBytesUsed", show currentBytesUsed)
                                        , ("currentBytesSlop", show currentBytesSlop)
                                        , ("maxBytesSlop", show maxBytesSlop)
                                        , ("peakMegabytesAllocated", show peakMegabytesAllocated)
                                        , ("mutatorCpuSeconds", show mutatorCpuSeconds)
                                        , ("mutatorWallSeconds", show mutatorWallSeconds)
                                        , ("gcCpuSeconds", show gcCpuSeconds)
                                        , ("gcWallSeconds", show gcWallSeconds)
                                        , ("cpuSeconds", show cpuSeconds)
                                        , ("wallSeconds", show wallSeconds)
                                        , ("parTotBytesCopied", show parTotBytesCopied)
                                        , ("parMaxBytesCopied", show parMaxBytesCopied)
                                        ]
                                hPutClient h $ showReport r
                            else hPutClient h "Run with +RTS -T to obtain live memory-usage information."
                        _ -> hPutClient h "error."

        ("ls", _) | Just DHT{dhtBuckets} <- Map.lookup netname dhts
                    -> cmd0 $ do
                        bkts <- atomically $ readTVar dhtBuckets
                        let r = reportTable bkts
                        hPutClient h $
                            showReport $
                                    r ++ [ ("buckets", show $ R.shape bkts)
                                         , ("node-id", show $ thisNode bkts)
                                         , ("network", netname) ]

        ("ping", s) | Just DHT{dhtPing} <- Map.lookup netname dhts
                    -> cmd0 $ do
                        case readEither s of
                          Right addr -> do result <- dhtPing addr
                                           let rs = [" ", show result]
                                           hPutClient h $ unlines rs
                          Left er -> hPutClient h er
        ("g", s) | Just DHT{..} <- Map.lookup netname dhts
                    -> cmd0 $ do
                        -- arguments: method
                        --            nid
                        --            (optional dest-ni)
                        self <- atomically $ thisNode <$> readTVar dhtBuckets
                        let (method,xs) = break isSpace $ dropWhile isSpace s
                            (nidstr,ys) = break isSpace $ dropWhile isSpace xs
                            destination = dropWhile isSpace ys
                            goQuery qry = either (hPutClient h . ("Bad search target: "++))
                                                 (goTarget qry)
                                                 $ dhtParseId nidstr
                            goTarget DHTQuery{..} nid =
                                go nid >>= reportResult method qshowR qshowTok show h
                              where
                                go | null destination = fmap Right . qhandler self
                                   | otherwise        = case readEither destination of
                                        Right ni -> fmap (maybe (Left "Timeout.") Right)
                                                    . flip (searchQuery qsearch) ni
                                        Left  e  -> const $ return $ Left ("Bad destination: "++e)
                        maybe (hPutClient h ("Unsupported method: "++method))
                              goQuery
                              $ Map.lookup method dhtQuery

        ("s", s) | Just dht@DHT{..} <- Map.lookup netname dhts
                    -> cmd0 $ do
                        let (method,xs) = break isSpace s
                            (nidstr,ys) = break isSpace $ dropWhile isSpace xs
                            presentSearches = hPutClient h
                                              =<< showSearches
                                              =<< atomically (readTVar dhtSearches)
                            goTarget qry nid = do
                                kvar <- atomically $ newTVar Nothing
                                -- Forking a thread, but it may ubruptly quit if the following
                                -- STM action decides not to add a new search.  This is so that
                                -- I can store the ThreadId into new DHTSearch structure.
                                tid <- fork $ join $ atomically (readTVar kvar >>= maybe retry return)
                                join $ atomically $ do
                                    schs <- readTVar dhtSearches
                                    case Map.lookup (method,nid) schs of
                                        Nothing  -> do forkSearch method nid qry dhtSearches dhtBuckets tid kvar
                                                       return $ presentSearches
                                        Just sch -> do writeTVar kvar (Just $ return ())
                                                       return $ reportSearchResults method h sch
                            goQuery qry = either (hPutClient h . ("Bad search target: "++))
                                                 (goTarget qry)
                                                 $ dhtParseId nidstr
                        if null method then presentSearches
                                       else maybe (hPutClient h ("Unsupported method: "++method))
                                                  goQuery
                                                  $ Map.lookup method dhtQuery

        ("x", s) | Just DHT{..} <- Map.lookup netname dhts
                    -> cmd0 $ do
                        let (method,xs) = break isSpace s
                            (nidstr,ys) = break isSpace $ dropWhile isSpace xs
                            go nid = join $ atomically $ do
                                schs <- readTVar dhtSearches
                                case Map.lookup (method,nid) schs of
                                    Nothing -> return $ hPutClient h "No match."
                                    Just DHTSearch{searchThread} -> do
                                        modifyTVar' dhtSearches (Map.delete (method,nid))
                                        return $ do
                                            killThread searchThread
                                            hPutClient h "Removed search."
                        either (hPutClient h . ("Bad search target: "++)) go $ dhtParseId nidstr

        ("save", _) | Just dht <- Map.lookup netname dhts
                    -> cmd0 $ do
                        saveNodes netname dht
                        hPutClient h $ "Saved " ++ nodesFileName netname ++ "."

        ("load", _) | Just dht <- Map.lookup netname dhts
                    -> cmd0 $ do
                        b <- pingNodes netname dht
                        if b then hPutClient h $ "Pinging " ++ nodesFileName netname ++ "."
                             else hPutClient h $ "Failed: " ++ nodesFileName netname ++ "."

        ("swarms", s) -> cmd0 $ do
                    let fltr = case s of
                                    ('-':'v':cs) | all isSpace (take 1 cs)
                                      -> const True
                                    _ -> (\(h,c,n) -> c/=0 )
                    ss <- atomically $ Peers.knownSwarms <$> readTVar (Mainline.contactInfo swarms)
                    let r = map (\(h,c,n) -> (unwords [show h,show c], maybe "" show n))
                            $ filter fltr ss
                    hPutClient h $ showReport r

        ("peers", s) -> cmd0 $ case readEither s of
                        Right ih -> do
                            ps <- atomically $ Peers.lookup ih <$> readTVar (Mainline.contactInfo swarms)
                            hPutClient h $ showReport $ map (((,) "") . show . pPrint) ps
                        Left er -> hPutClient h er

        (n, _) | n `elem` Map.keys dhts -> switchNetwork n

        _    -> cmd0 $ hPutClient h "error."


readExternals :: [TVar (BucketList Mainline.NodeInfo)] -> IO [SockAddr]
readExternals vars = do
    as <- atomically $ mapM (fmap (Mainline.nodeAddr . selfNode) . readTVar) vars
    let unspecified (SockAddrInet _ 0)              = True
        unspecified (SockAddrInet6 _ _ (0,0,0,0) _) = True
        unspecified _                               = False
    -- TODO: Filter to only global addresses?
    return $ filter (not . unspecified) as

defaultPort = "6881"

main = do
    args <- getArgs
    p <- case take 2 (dropWhile (/="-p") args) of
                ["-p",port] | not ("-" `isPrefixOf` port) -> return port
                ("-p":_)      -> error "Port not specified! (-p PORT)"
                _             -> return defaultPort
    addr <- getBindAddress p True{- ipv6 -}

    (bt,btR,swarms) <- Mainline.newClient addr

    -- Restore peer database before forking the listener thread.
    peerdb <- left show <$> tryIOError (L.readFile "bt-peers.dat")
    either (hPutStrLn stderr . ("bt-peers.dat: "++))
           (atomically . writeTVar (Mainline.contactInfo swarms))
           (peerdb >>= S.decodeLazy)

    quitBt <- forkListener bt

    let toxport = succ $ fromMaybe 33445 (fromIntegral <$> sockAddrPort addr)
    addrTox <- getBindAddress (show toxport) True
    (tox,toxR) <- Tox.newClient addrTox

    -- TODO: load saved tox nodes.

    quitTox <- forkListener tox

    mainlineSearches <- atomically $ newTVar Map.empty
    toxSearches <- atomically $ newTVar Map.empty

    let mainlineDHT bkts = DHT
            { dhtBuckets = bkts btR
            , dhtPing    = Mainline.ping bt
            , dhtQuery   = Map.fromList
                            [ ("node", DHTQuery (Mainline.nodeSearch bt)
                                                (\ni -> fmap Mainline.unwrapNodes
                                                        . Mainline.findNodeH btR ni
                                                        . flip Mainline.FindNode (Just Want_Both))
                                                show
                                                (const Nothing))
                            , ("peer", DHTQuery (Mainline.peerSearch bt)
                                                (\ni -> fmap Mainline.unwrapPeers
                                                        . Mainline.getPeersH btR swarms ni
                                                        . flip Mainline.GetPeers (Just Want_Both)
                                                        . (read . show)) -- TODO: InfoHash -> NodeId
                                                (show . pPrint)
                                                (Just . show))
                            ]
            , dhtParseId  = readEither :: String -> Either String Mainline.NodeId
            , dhtSearches = mainlineSearches
            }
        toxDHT bkts = DHT
            { dhtBuckets = bkts toxR
            , dhtPing    = Tox.ping tox
            , dhtQuery   = Map.fromList
                            [ -- "node"
                            ]
            , dhtParseId  = readEither :: String -> Either String Tox.NodeId
            , dhtSearches = toxSearches
            }
        dhts = Map.fromList
                [ ("bt4", mainlineDHT Mainline.routing4)
                , ("bt6", mainlineDHT Mainline.routing6)
                , ("tox4", toxDHT Tox.routing4)
                , ("tox6", toxDHT Tox.routing6)
                ]

    waitForSignal <- do
        signalQuit <- newEmptyMVar
        let session = clientSession $ Session
                { netname           = "bt4" -- initial default DHT
                , dhts              = dhts  -- all DHTs
                , signalQuit        = signalQuit
                , swarms            = swarms
                , externalAddresses = readExternals
                                        [ Mainline.routing4 btR
                                        , Mainline.routing6 btR
                                        ]
                }
        srv <- streamServer (withSession session) (SockAddrUnix "dht.sock")
        return $ do
            () <- takeMVar signalQuit
            quitListening srv

    let bkts4 = Mainline.routing4 btR
    btSaved4 <- loadNodes "bt4" :: IO [Mainline.NodeInfo]
    putStrLn $ "Loaded "++show (length btSaved4)++" nodes for bt4."
    fallbackNodes4 <- Mainline.bootstrapNodes Want_IP4
    fork $ do
        myThreadId >>= flip labelThread "bootstrap.Mainline4"
        bootstrap (Mainline.nodeSearch bt) bkts4 (Mainline.ping bt) btSaved4 fallbackNodes4
        saveNodes "bt4" (dhts Map.! "bt4")

    btSaved6 <- loadNodes "bt6"
    putStrLn $ "Loaded "++show (length btSaved6)++" nodes for bt6."
    let bkts6 = Mainline.routing6 btR
    fallbackNodes6 <- Mainline.bootstrapNodes Want_IP6
    fork $ do
        myThreadId >>= flip labelThread "bootstrap.Mainline6"
        bootstrap (Mainline.nodeSearch bt) bkts6 (Mainline.ping bt) btSaved6 fallbackNodes6
        saveNodes "bt6" (dhts Map.! "bt6")

    hPutStr stderr $ showReport $ map (("bootstrap (IPv4)",) . show) fallbackNodes4
                                  ++ map (("bootstrap (IPv6)",) . show) fallbackNodes6

    waitForSignal

    quitBt
    quitTox

    swarmsdb <- atomically $ readTVar (Mainline.contactInfo swarms)
    L.writeFile "bt-peers.dat" $ S.encodeLazy swarmsdb