From: Ramakrishnan Muthukrishnan Date: Fri, 4 Sep 2015 06:15:39 +0000 (+0530) Subject: Peer: refactor pickPiece function X-Git-Url: https://git.rkrishnan.org/%5B/%5D%20/file/URI:LIT:krugkidfnzsc4/%22news.html//%22%22.?a=commitdiff_plain;h=205bce74b5786543949b162203a6e8e61e72f5f9;p=functorrent.git Peer: refactor pickPiece function Use the headMay from the Safe package to get a Maybe list head and lift fst to Maybe to get the key. --- diff --git a/functorrent.cabal b/functorrent.cabal index 2db1119..2ec81bb 100644 --- a/functorrent.cabal +++ b/functorrent.cabal @@ -42,6 +42,7 @@ library network-uri, parsec, QuickCheck, + safe, tasty, tasty-hunit @@ -63,7 +64,8 @@ executable functorrent network, network-uri, parsec, - QuickCheck + QuickCheck, + safe test-suite functorrent-test type: exitcode-stdio-1.0 diff --git a/src/FuncTorrent/Peer.hs b/src/FuncTorrent/Peer.hs index 5e23fa1..0b9ece7 100644 --- a/src/FuncTorrent/Peer.hs +++ b/src/FuncTorrent/Peer.hs @@ -4,7 +4,7 @@ module FuncTorrent.Peer handlePeerMsgs ) 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) @@ -13,8 +13,9 @@ import Network (connectTo, PortID(..)) 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) @@ -102,13 +103,8 @@ toPeerState h p meCh meIn heCh heIn = -- 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) updatePieceAvailability :: PieceMap -> Peer -> [Integer] -> PieceMap updatePieceAvailability pieceStatus p pieceList =