netlines (empty) → 0.1.0

raw patch · 4 files changed

+172/−0 lines, 4 filesdep +basedep +bytestringdep +contstuffsetup-changed

Dependencies added: base, bytestring, contstuff, enumerator

Files

• LICENSE +32/−0
• Network/NetLines.hs +100/−0
• Setup.lhs +12/−0
• netlines.cabal +28/−0

@@ -0,0 +1,32 @@+netlines license+Copyright (c) 2010, Ertugrul Soeylemez++All rights reserved.++Redistribution and use in source and binary forms, with or without+modification, are permitted provided that the following conditions are+met:++    * Redistributions of source code must retain the above copyright+      notice, this list of conditions and the following disclaimer.++    * Redistributions in binary form must reproduce the above copyright+      notice, this list of conditions and the following disclaimer in+      the documentation and/or other materials provided with the+      distribution.++    * Neither the name of the author nor the names of any contributors+      may be used to endorse or promote products derived from this+      software without specific prior written permission.++THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS+IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED+TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A+PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER+OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,+EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,+PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR+PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

@@ -0,0 +1,100 @@+-- |+-- Module:     Network.NetLines+-- Copyright:  (c) 2010 Ertugrul Soeylemez+-- License:    BSD3+-- Maintainer: Ertugrul Soeylemez <es@ertes.de>+-- Stability:  experimental+--+-- Enumerator tools for working with text-based network protocols.++{-# LANGUAGE ScopedTypeVariables #-}++module Network.NetLines+    ( -- * Conversion to lines+      netLine,+      netLines,++      -- * Enumerators+      enumHandleTimeout+    )+    where++import qualified Data.ByteString as B+import Control.ContStuff+import Data.ByteString (ByteString)+import Data.Enumerator as E+import Data.Enumerator.Binary as EB+import Data.Word+import System.IO+import System.IO.Error as IOErr+++-- | Enumerate from a handle with the given buffer size (first argument)+-- and timeout in milliseconds (second argument).  If the timeout is+-- exceeded an exception is thrown via 'throwError'.++enumHandleTimeout :: forall b m. MonadIO m =>+                     Int -> Int -> Handle -> Enumerator ByteString m b+enumHandleTimeout bufSize timeout h = loop+    where+    loop :: Enumerator ByteString m b+    loop (Continue k) = do+          mHaveInput <- liftIO $ IOErr.try (hWaitForInput h timeout)+          case mHaveInput of+            Left err+                | isEOFError err -> continue k+                | otherwise      -> throwError err+            Right False -> throwError $ userError "Handle timed out"+            Right True  -> do+                mStr <- liftIO $ IOErr.try (B.hGetNonBlocking h bufSize)+                str <- either throwError return mStr+                if B.null str+                  then continue k+                  else k (Chunks [str]) >>== loop+    loop step = returnI step+++-- | Savely read a line with the given maximum length.  If a longer line+-- is enumerated, the excess data is dropped in constant space.  Returns+-- 'Nothing' on EOF.+--+-- Please note that this function is very error-tolerant in the way it+-- handles line endings.  Both CR and LF are proper line terminators.+-- This function ignores empty lines.++netLine :: forall m r. Monad m => Int -> MaybeT r (Iteratee ByteString m) ByteString+netLine n =+    lift (EB.dropWhile isEol) >> netLine' n++    where+    isEol :: Word8 -> Bool+    isEol 10 = True+    isEol 13 = True+    isEol _  = False++    isNotEol :: Word8 -> Bool+    isNotEol = not . isEol++    netLine' :: Int -> MaybeT r (Iteratee ByteString m) ByteString+    netLine' 0 = B.empty <$ lift (EB.dropWhile isNotEol)+    netLine' n = do+        c <- liftF EB.head+        if isNotEol c+          then B.cons c <$> netLine' (n-1)+          else return B.empty+++-- | Convert a stream of bytes to a stream of lines with the given+-- maximum length.  Longer lines are silently truncated in constant+-- space.++netLines :: forall b m. Monad m => Int -> Enumeratee ByteString ByteString m b+netLines maxLen = loop+    where+    loop :: Enumeratee ByteString ByteString m b+    loop (Continue k) = do+        mLine <- evalMaybeT $ netLine maxLen+        case mLine of+          Just line -> k (Chunks [line]) >>== loop+          Nothing   -> k EOF >>== loop+    loop step = return step

@@ -0,0 +1,12 @@+netlines setup script+Copyright (C) 2010, Ertugrul Soeylemez++Please see the LICENSE file for terms and conditions of use,+modification and distribution of this package, including this file.++> module Main where+>+> import Distribution.Simple+>+> main :: IO ()+> main = defaultMain

@@ -0,0 +1,28 @@+Name:          netlines+Version:       0.1.0+Category:      Network+Synopsis:      Enumerator tools for text-based network protocols+Maintainer:    Ertugrul Söylemez <es@ertes.de>+Author:        Ertugrul Söylemez <es@ertes.de>+Copyright:     (c) 2010 Ertugrul Söylemez+License:       BSD3+License-file:  LICENSE+Build-type:    Simple+Stability:     experimental+Cabal-version: >= 1.6+Description:++    Enumerator tools for text-based network protocols.  This includes,+    among other things, an enumeratee to split an incoming ByteString+    stream to a length-limited line stream in a safe manner+    (i.e. constant space).++Library+  Build-depends:+    base >= 4 && <= 5,+    bytestring >= 0.9.1.7,+    contstuff >= 1.2.4,+    enumerator >= 0.4.7+  GHC-Options:   -W+  Exposed-modules:+    Network.NetLines