From 1d114193577940b181252c097fcd61366158ce7c Mon Sep 17 00:00:00 2001
From: Ramakrishnan Muthukrishnan <ram@rkrishnan.org>
Date: Sun, 13 Sep 2015 22:22:17 +0530
Subject: [PATCH] a crude server implementation

---
 functorrent.cabal         |  1 +
 src/FuncTorrent/Server.hs | 25 +++++++++++++++++++++++++
 src/main/Main.hs          |  7 ++++++-
 3 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 src/FuncTorrent/Server.hs

diff --git a/functorrent.cabal b/functorrent.cabal
index dd0a306..b937472 100644
--- a/functorrent.cabal
+++ b/functorrent.cabal
@@ -23,6 +23,7 @@ library
                        FuncTorrent.Network
                        FuncTorrent.Peer,
                        FuncTorrent.PeerMsgs,
+                       FuncTorrent.Server,
                        FuncTorrent.Tracker,
                        FuncTorrent.Utils
 
diff --git a/src/FuncTorrent/Server.hs b/src/FuncTorrent/Server.hs
new file mode 100644
index 0000000..e675c6c
--- /dev/null
+++ b/src/FuncTorrent/Server.hs
@@ -0,0 +1,25 @@
+{-# LANGUAGE OverloadedStrings #-}
+module FuncTorrent.Server where
+
+import Control.Concurrent (forkIO)
+import Control.Monad (forever)
+import Network (withSocketsDo, listenOn, accept, Socket, PortID ( PortNumber ))
+import System.IO (hSetBuffering, BufferMode ( NoBuffering ))
+
+import FuncTorrent.Metainfo (Metainfo)
+import FuncTorrent.Peer (handlePeerMsgs, Peer(..))
+
+-- server is listening on any port from 6881 - 6889
+-- return the port number used
+start :: IO (Socket, PortID)
+start = withSocketsDo $ do
+  let portnums = [6881 .. 6889]
+  sock <- listenOn $ PortNumber $ fromIntegral (head portnums)
+  return (sock, PortNumber $ head portnums)
+
+run :: Socket -> String -> Metainfo -> IO ()
+run listenSock peerid m = forever $ do
+  (handle, ip, port) <- accept listenSock
+  let peer = Peer "" ip (fromIntegral port)
+  hSetBuffering handle NoBuffering
+  forkIO $ handlePeerMsgs peer peerid m
diff --git a/src/main/Main.hs b/src/main/Main.hs
index dff915f..997801b 100644
--- a/src/main/Main.hs
+++ b/src/main/Main.hs
@@ -3,6 +3,7 @@ module Main where
 
 import Prelude hiding (log, length, readFile, getContents)
 
+import Control.Concurrent (forkIO)
 import Data.ByteString.Char8 (ByteString, getContents, readFile, unpack)
 import System.Environment (getArgs)
 import System.Exit (exitSuccess)
@@ -12,6 +13,7 @@ import System.Random (getStdGen, randomRs)
 import FuncTorrent.Logger (initLogger, logMessage, logStop)
 import FuncTorrent.Metainfo (Info(..), Metainfo(..), torrentToMetainfo)
 import FuncTorrent.Peer (handlePeerMsgs)
+import qualified FuncTorrent.Server as Server
 import FuncTorrent.Tracker (peers, getTrackerResponse)
 
 logError :: String -> (String -> IO ()) -> IO ()
@@ -56,8 +58,11 @@ main = do
      Right m -> do
        log "Input File OK"
        log $ "Downloading file : " ++ name (info m)
-       log "Trying to fetch peers"
 
+       log $ "starting server"
+       (serverSock, portnum) <- Server.start
+       log "Trying to fetch peers"
+       forkIO $ Server.run serverSock peerId m
        log $ "Trackers: " ++ head (announceList m)
        trackerResp <- getTrackerResponse peerId m
        case  trackerResp of
-- 
2.37.2