{-# OPTIONS_GHC -cpp -fglasgow-exts -fno-warn-orphans #-}
---
--- Module : ByteString
+-- |
+-- Module : Data.ByteString
-- Copyright : (c) The University of Glasgow 2001,
-- (c) David Roundy 2003-2005,
-- (c) Simon Marlow 2005
-- (c) Don Stewart 2005-2006
-- (c) Bjorn Bringert 2006
---
--- Array fusion code:
+-- Array fusion code:
-- (c) 2001,2002 Manuel M T Chakravarty & Gabriele Keller
-- (c) 2006 Manuel M T Chakravarty & Roman Leshchinskiy
--
--
-- Maintainer : dons@cse.unsw.edu.au
-- Stability : experimental
--- Portability : portable, requires ffi and cpp
--- Tested with : GHC 6.4.1 and Hugs March 2005
+-- Portability : portable
--
-
---
--- | A time and space-efficient implementation of byte vectors using
+-- A time and space-efficient implementation of byte vectors using
-- packed Word8 arrays, suitable for high performance use, both in terms
-- of large data quantities, or high speed requirements. Byte vectors
-- are encoded as strict 'Word8' arrays of bytes, held in a 'ForeignPtr',
--
-- > import qualified Data.ByteString as B
--
--- Original GHC implementation by Bryan O\'Sullivan. Rewritten to use
--- UArray by Simon Marlow. Rewritten to support slices and use
--- ForeignPtr by David Roundy. Polished and extended by Don Stewart.
+-- Original GHC implementation by Bryan O\'Sullivan.
+-- Rewritten to use 'Data.Array.Unboxed.UArray' by Simon Marlow.
+-- Rewritten to support slices and use 'ForeignPtr' by David Roundy.
+-- Polished and extended by Don Stewart.
--
module Data.ByteString (
singleton, -- :: Word8 -> ByteString
pack, -- :: [Word8] -> ByteString
unpack, -- :: ByteString -> [Word8]
- packWith, -- :: (a -> Word8) -> [a] -> ByteString
- unpackWith, -- :: (Word8 -> a) -> ByteString -> [a]
-- * Basic interface
cons, -- :: Word8 -> ByteString -> ByteString
-- * Transformating ByteStrings
map, -- :: (Word8 -> Word8) -> ByteString -> ByteString
- map', -- :: (Word8 -> Word8) -> ByteString -> ByteString
reverse, -- :: ByteString -> ByteString
intersperse, -- :: Word8 -> ByteString -> ByteString
transpose, -- :: [ByteString] -> [ByteString]
foldl', -- :: (a -> Word8 -> a) -> a -> ByteString -> a
foldl1, -- :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8
foldl1', -- :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8
+
foldr, -- :: (Word8 -> a -> a) -> a -> ByteString -> a
+ foldr', -- :: (Word8 -> a -> a) -> a -> ByteString -> a
foldr1, -- :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8
+ foldr1', -- :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8
-- ** Special folds
concat, -- :: [ByteString] -> ByteString
-- ** Unfolding ByteStrings
replicate, -- :: Int -> Word8 -> ByteString
unfoldr, -- :: (a -> Maybe (Word8, a)) -> a -> ByteString
- unfoldrN, -- :: Int -> (a -> Maybe (Word8, a)) -> a -> ByteString
+ unfoldrN, -- :: Int -> (a -> Maybe (Word8, a)) -> a -> (ByteString, Maybe a)
-- * Substrings
inits, -- :: ByteString -> [ByteString]
tails, -- :: ByteString -> [ByteString]
- -- ** Breaking and dropping on specific bytes
- breakByte, -- :: Word8 -> ByteString -> (ByteString, ByteString)
- spanByte, -- :: Word8 -> ByteString -> (ByteString, ByteString)
-
-- ** Breaking into many substrings
split, -- :: Word8 -> ByteString -> [ByteString]
splitWith, -- :: (Word8 -> Bool) -> ByteString -> [ByteString]
- tokens, -- :: (Word8 -> Bool) -> ByteString -> [ByteString]
-- ** Joining strings
join, -- :: ByteString -> [ByteString] -> ByteString
- joinWithByte, -- :: Word8 -> ByteString -> ByteString -> ByteString
-- * Predicates
isPrefixOf, -- :: ByteString -> ByteString -> Bool
-- | These functions use memchr(3) to efficiently search the ByteString
elem, -- :: Word8 -> ByteString -> Bool
notElem, -- :: Word8 -> ByteString -> Bool
- filterByte, -- :: Word8 -> ByteString -> ByteString
- filterNotByte, -- :: Word8 -> ByteString -> ByteString
-- ** Searching with a predicate
find, -- :: (Word8 -> Bool) -> ByteString -> Maybe Word8
filter, -- :: (Word8 -> Bool) -> ByteString -> ByteString
- filter', -- :: (Word8 -> Bool) -> ByteString -> ByteString
-- partition -- :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
-- * Indexing ByteStrings
findIndex, -- :: (Word8 -> Bool) -> ByteString -> Maybe Int
findIndices, -- :: (Word8 -> Bool) -> ByteString -> [Int]
count, -- :: Word8 -> ByteString -> Int
- findIndexOrEnd, -- :: (Word8 -> Bool) -> ByteString -> Int
-- * Zipping and unzipping ByteStrings
zip, -- :: ByteString -> ByteString -> [(Word8,Word8)]
zipWith, -- :: (Word8 -> Word8 -> c) -> ByteString -> ByteString -> [c]
- zipWith',
unzip, -- :: [(Word8,Word8)] -> (ByteString,ByteString)
-- * Ordered ByteStrings
-- * I\/O with 'ByteString's
-- ** Standard input and output
-
-#if defined(__GLASGOW_HASKELL__)
getLine, -- :: IO ByteString
-#endif
getContents, -- :: IO ByteString
putStr, -- :: ByteString -> IO ()
putStrLn, -- :: ByteString -> IO ()
+ interact, -- :: (ByteString -> ByteString) -> IO ()
-- ** Files
readFile, -- :: FilePath -> IO ByteString
-- mmapFile, -- :: FilePath -> IO ByteString
-- ** I\/O with Handles
-#if defined(__GLASGOW_HASKELL__)
- getArgs, -- :: IO [ByteString]
hGetLine, -- :: Handle -> IO ByteString
- hGetLines, -- :: Handle -> IO [ByteString]
- hGetNonBlocking, -- :: Handle -> Int -> IO ByteString
-#endif
hGetContents, -- :: Handle -> IO ByteString
hGet, -- :: Handle -> Int -> IO ByteString
+ hGetNonBlocking, -- :: Handle -> Int -> IO ByteString
hPut, -- :: Handle -> ByteString -> IO ()
hPutStr, -- :: Handle -> ByteString -> IO ()
hPutStrLn, -- :: Handle -> ByteString -> IO ()
- -- * Fusion utilities
#if defined(__GLASGOW_HASKELL__)
+ -- * Fusion utilities
unpackList, -- eek, otherwise it gets thrown away by the simplifier
-#endif
lengthU, maximumU, minimumU
+#endif
+
) where
import qualified Prelude as P
,minimum,all,concatMap,foldl1,foldr1
,scanl,scanl1,scanr,scanr1
,readFile,writeFile,appendFile,replicate
- ,getContents,getLine,putStr,putStrLn
+ ,getContents,getLine,putStr,putStrLn,interact
,zip,zipWith,unzip,notElem)
import Data.ByteString.Base
-- Control.Exception.bracket not available in yhc or nhc
import Control.Exception (bracket, assert)
+import qualified Control.Exception as Exception
import Control.Monad (when)
import Foreign.C.String (CString, CStringLen)
#if !defined(__GLASGOW_HASKELL__)
import System.IO.Unsafe
+import qualified System.Environment
+import qualified System.IO (hGetLine)
#endif
#if defined(__GLASGOW_HASKELL__)
import System.IO (hGetBufNonBlocking)
import System.IO.Error (isEOFError)
-import Foreign.Marshal (alloca)
-import qualified Foreign.Concurrent as FC (newForeignPtr)
-
import GHC.Handle
import GHC.Prim (Word#, (+#), writeWord8OffAddr#)
import GHC.Base (build)
instance Ord ByteString
where compare = compareBytes
-instance Show ByteString where
- showsPrec p ps r = showsPrec p (unpackWith w2c ps) r
-
-instance Read ByteString where
- readsPrec p str = [ (packWith c2w x, y) | (x, y) <- readsPrec p str ]
-
instance Monoid ByteString where
mempty = empty
mappend = append
-- -----------------------------------------------------------------------------
-- Introducing and eliminating 'ByteString's
--- | /O(1)/ The empty 'ByteString'
-empty :: ByteString
-empty = unsafeCreate 0 $ const $ return ()
-{-# NOINLINE empty #-}
-
-- | /O(1)/ Convert a 'Word8' into a 'ByteString'
singleton :: Word8 -> ByteString
singleton c = unsafeCreate 1 $ \p -> poke p c
-{-# INLINE singleton #-}
+{-# INLINE [1] singleton #-}
--
-- XXX The unsafePerformIO is critical!
unpack ps = build (unpackFoldr ps)
{-# INLINE unpack #-}
+--
+-- critical this isn't strict in the acc
+-- as it will break in the presence of list fusion. this is a known
+-- issue with seq and build/foldr rewrite rules, which rely on lazy
+-- demanding to avoid bottoms in the list.
+--
+unpackFoldr :: ByteString -> (Word8 -> a -> a) -> a -> a
+unpackFoldr (PS fp off len) f ch = withPtr fp $ \p -> do
+ let loop q n _ | q `seq` n `seq` False = undefined -- n.b.
+ loop _ (-1) acc = return acc
+ loop q n acc = do
+ a <- peekByteOff q n
+ loop q (n-1) (a `f` acc)
+ loop (p `plusPtr` off) (len-1) ch
+{-# INLINE [0] unpackFoldr #-}
+
unpackList :: ByteString -> [Word8]
unpackList (PS fp off len) = withPtr fp $ \p -> do
let STRICT3(loop)
loop (p `plusPtr` off) (len-1) []
{-# RULES
-"unpack-list" [1] forall p . unpackFoldr p (:) [] = unpackList p
+ "FPS unpack-list" [1] forall p . unpackFoldr p (:) [] = unpackList p
#-}
-unpackFoldr :: ByteString -> (Word8 -> a -> a) -> a -> a
-unpackFoldr (PS fp off len) f ch = withPtr fp $ \p -> do
- let STRICT3(loop)
- loop _ (-1) acc = return acc
- loop q n acc = do
- a <- peekByteOff q n
- loop q (n-1) (a `f` acc)
- loop (p `plusPtr` off) (len-1) ch
-{-# INLINE [0] unpackFoldr #-}
-
--- TODO just use normal foldr here.
---
--- or
--- unpack xs | null xs = []
--- | otherwise = unsafeHead xs : unpack (unsafeTail xs)
---
--- ?
-
#endif
-------------------------------------------------------------------------
-
--- | /O(n)/ Convert a '[a]' into a 'ByteString' using some
--- conversion function
-packWith :: (a -> Word8) -> [a] -> ByteString
-packWith k str = unsafeCreate (P.length str) $ \p -> go p str
- where
- STRICT2(go)
- go _ [] = return ()
- go p (x:xs) = poke p (k x) >> go (p `plusPtr` 1) xs -- less space than pokeElemOff
-{-# INLINE packWith #-}
-{-# SPECIALIZE packWith :: (Char -> Word8) -> [Char] -> ByteString #-}
-
--- | /O(n)/ Converts a 'ByteString' to a '[a]', using a conversion function.
-unpackWith :: (Word8 -> a) -> ByteString -> [a]
-unpackWith _ (PS _ _ 0) = []
-unpackWith k (PS ps s l) = inlinePerformIO $ withForeignPtr ps $ \p ->
- go (p `plusPtr` s) (l - 1) []
- where
- STRICT3(go)
- go p 0 acc = peek p >>= \e -> return (k e : acc)
- go p n acc = peekByteOff p n >>= \e -> go p (n-1) (k e : acc)
-{-# INLINE unpackWith #-}
-{-# SPECIALIZE unpackWith :: (Word8 -> Char) -> ByteString -> [Char] #-}
-
-- ---------------------------------------------------------------------
-- Basic interface
{-# RULES
-- v2 fusion
-"length/loop" forall loop s .
+"FPS length/loop" forall loop s .
length (loopArr (loopWrapper loop s)) =
lengthU (loopArr (loopWrapper loop s))
#endif
{-# INLINE map #-}
+{-
-- | /O(n)/ Like 'map', but not fuseable. The benefit is that it is
-- slightly faster for one-shot cases.
map' :: (Word8 -> Word8) -> ByteString -> ByteString
pokeByteOff p2 n (f x)
map_ (n+1) p1 p2
{-# INLINE map' #-}
+-}
-- | /O(n)/ 'reverse' @xs@ efficiently returns the elements of @xs@ in reverse order.
reverse :: ByteString -> ByteString
foldr k z = loopAcc . loopDown (foldEFL (flip k)) z
{-# INLINE foldr #-}
+-- | 'foldr\'' is like 'foldr', but strict in the accumulator.
+foldr' :: (Word8 -> a -> a) -> a -> ByteString -> a
+foldr' k v (PS x s l) = inlinePerformIO $ withForeignPtr x $ \ptr ->
+ go v (ptr `plusPtr` (s+l-1)) (ptr `plusPtr` (s-1))
+ where
+ STRICT3(go)
+ go z p q | p == q = return z
+ | otherwise = do c <- peek p
+ go (c `k` z) (p `plusPtr` (-1)) q -- tail recursive
+{-# INLINE [1] foldr' #-}
+
-- | 'foldl1' is a variant of 'foldl' that has no starting value
-- argument, and thus must be applied to non-empty 'ByteStrings'.
-- This function is subject to array fusion.
| otherwise = foldr f (last ps) (init ps)
{-# INLINE foldr1 #-}
+-- | 'foldr1\'' is a variant of 'foldr1', but is strict in the
+-- accumulator.
+foldr1' :: (Word8 -> Word8 -> Word8) -> ByteString -> Word8
+foldr1' f ps
+ | null ps = errorEmptyList "foldr1"
+ | otherwise = foldr' f (last ps) (init ps)
+{-# INLINE [1] foldr1' #-}
+
-- ---------------------------------------------------------------------
-- Special folds
{-# RULES
-"minimum/loop" forall loop s .
+"FPS minimum/loop" forall loop s .
minimum (loopArr (loopWrapper loop s)) =
minimumU (loopArr (loopWrapper loop s))
-"maximum/loop" forall loop s .
+"FPS maximum/loop" forall loop s .
maximum (loopArr (loopWrapper loop s)) =
maximumU (loopArr (loopWrapper loop s))
-- | 'break' @p@ is equivalent to @'span' ('not' . p)@.
break :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
break p ps = case findIndexOrEnd p ps of n -> (unsafeTake n ps, unsafeDrop n ps)
-{-# INLINE break #-}
+{-# INLINE [1] break #-}
--- | 'breakEnd' behaves like 'break' but from the end of the 'ByteString'
---
--- breakEnd p == spanEnd (not.p)
-breakEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
-breakEnd p ps = splitAt (findFromEndUntil p ps) ps
+{-# RULES
+"FPS specialise break (x==)" forall x.
+ break ((==) x) = breakByte x
+ #-}
+
+#if __GLASGOW_HASKELL__ >= 605
+{-# RULES
+"FPS specialise break (==x)" forall x.
+ break (==x) = breakByte x
+ #-}
+#endif
-- | 'breakByte' breaks its ByteString argument at the first occurence
-- of the specified byte. It is more efficient than 'break' as it is
Just n -> (unsafeTake n p, unsafeDrop n p)
{-# INLINE breakByte #-}
+-- | 'breakEnd' behaves like 'break' but from the end of the 'ByteString'
+--
+-- breakEnd p == spanEnd (not.p)
+breakEnd :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
+breakEnd p ps = splitAt (findFromEndUntil p ps) ps
+
+-- | 'span' @p xs@ breaks the ByteString into two segments. It is
+-- equivalent to @('takeWhile' p xs, 'dropWhile' p xs)@
+span :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
+span p ps = break (not . p) ps
+{-# INLINE [1] span #-}
+
-- | 'spanByte' breaks its ByteString argument at the first
-- occurence of a byte other than its argument. It is more efficient
-- than 'span (==)'
else go p (i+1)
{-# INLINE spanByte #-}
--- | 'span' @p xs@ breaks the ByteString into two segments. It is
--- equivalent to @('takeWhile' p xs, 'dropWhile' p xs)@
-span :: (Word8 -> Bool) -> ByteString -> (ByteString, ByteString)
-span p ps = break (not . p) ps
-{-# INLINE span #-}
+{-# RULES
+"FPS specialise span (x==)" forall x.
+ span ((==) x) = spanByte x
+ #-}
+
+#if __GLASGOW_HASKELL__ >= 605
+{-# RULES
+"FPS specialise span (==x)" forall x.
+ span (==x) = spanByte x
+ #-}
+#endif
-- | 'spanEnd' behaves like 'span' but from the end of the 'ByteString'.
-- We have
-- argument, consuming the delimiter. I.e.
--
-- > split '\n' "a\nb\nd\ne" == ["a","b","d","e"]
--- > split 'a' "aXaXaXa" == ["","X","X","X"]
+-- > split 'a' "aXaXaXa" == ["","X","X","X",""]
-- > split 'x' "x" == ["",""]
--
-- and
else splitLoop p (idx'+1) off' len' fp'
-}
+{-
-- | Like 'splitWith', except that sequences of adjacent separators are
-- treated as a single separator. eg.
--
tokens :: (Word8 -> Bool) -> ByteString -> [ByteString]
tokens f = P.filter (not.null) . splitWith f
{-# INLINE tokens #-}
+-}
-- | The 'group' function takes a ByteString and returns a list of
-- ByteStrings such that the concatenation of the result is equal to the
-- argument between each element of the list.
join :: ByteString -> [ByteString] -> ByteString
join s = concat . (List.intersperse s)
-{-# INLINE join #-}
+{-# INLINE [1] join #-}
+
+{-# RULES
+"FPS specialise join c -> joinByte" forall c s1 s2 .
+ join (singleton c) (s1 : s2 : []) = joinWithByte c s1 s2
+ #-}
--
-- | /O(n)/ joinWithByte. An efficient way to join to two ByteStrings
| p (unsafeHead qs) = n : loop (n+1) (unsafeTail qs)
| otherwise = loop (n+1) (unsafeTail qs)
--- | 'findIndexOrEnd' is a variant of findIndex, that returns the length
--- of the string if no element is found, rather than Nothing.
-findIndexOrEnd :: (Word8 -> Bool) -> ByteString -> Int
-findIndexOrEnd k (PS x s l) = inlinePerformIO $ withForeignPtr x $ \f -> go (f `plusPtr` s) 0
- where
- STRICT2(go)
- go ptr n | n >= l = return l
- | otherwise = do w <- peek ptr
- if k w
- then return n
- else go (ptr `plusPtr` 1) (n+1)
-{-# INLINE findIndexOrEnd #-}
-
-- ---------------------------------------------------------------------
-- Searching ByteStrings
#endif
{-# INLINE filter #-}
+{-
-- | /O(n)/ 'filter\'' is a non-fuseable version of filter, that may be
-- around 2x faster for some one-shot applications.
filter' :: (Word8 -> Bool) -> ByteString -> ByteString
then poke t w >> go (f `plusPtr` 1) (t `plusPtr` 1) end
else go (f `plusPtr` 1) t end
{-# INLINE filter' #-}
+-}
--
-- | /O(n)/ A first order equivalent of /filter . (==)/, for the common
filterByte w ps = replicate (count w ps) w
{-# INLINE filterByte #-}
+{-# RULES
+ "FPS specialise filter (== x)" forall x.
+ filter ((==) x) = filterByte x
+ #-}
+
+#if __GLASGOW_HASKELL__ >= 605
+{-# RULES
+ "FPS specialise filter (== x)" forall x.
+ filter (== x) = filterByte x
+ #-}
+#endif
+
--
-- | /O(n)/ A first order equivalent of /filter . (\/=)/, for the common
-- case of filtering a single byte out of a list. It is more efficient
--
-- filterNotByte is around 2x faster than its filter equivalent.
filterNotByte :: Word8 -> ByteString -> ByteString
-filterNotByte w = filter' (/= w)
+filterNotByte w = filter (/= w)
{-# INLINE filterNotByte #-}
+{-# RULES
+"FPS specialise filter (x /=)" forall x.
+ filter ((/=) x) = filterNotByte x
+ #-}
+
+#if __GLASGOW_HASKELL__ >= 605
+{-# RULES
+"FPS specialise filter (/= x)" forall x.
+ filter (/= x) = filterNotByte x
+ #-}
+#endif
+
-- | /O(n)/ The 'find' function takes a predicate and a ByteString,
-- and returns the first element in matching the predicate, or 'Nothing'
-- if there is no such element.
zipWith f ps qs
| null ps || null qs = []
| otherwise = f (unsafeHead ps) (unsafeHead qs) : zipWith f (unsafeTail ps) (unsafeTail qs)
+#if defined(__GLASGOW_HASKELL__)
+{-# INLINE [1] zipWith #-}
+#endif
--
-- | A specialised version of zipWith for the common case of a
{-# RULES
-"Specialise zipWith" forall (f :: Word8 -> Word8 -> Word8) p q .
- pack (zipWith f p q) = zipWith' f p q
+"FPS specialise zipWith" forall (f :: Word8 -> Word8 -> Word8) p q .
+ zipWith f p q = unpack (zipWith' f p q)
+
#-}
-- | /O(n)/ 'unzip' transforms a list of pairs of bytes into a pair of
-- null-terminated @CString@. The @CString@ will be freed
-- automatically. This is a memcpy(3).
useAsCString :: ByteString -> (CString -> IO a) -> IO a
-useAsCString ps f = useAsCStringLen ps (\(s,_) -> f s)
-
--- | /O(n) construction/ Use a @ByteString@ with a function requiring a
--- @CStringLen@. The @CStringLen@ will be freed automatically. This is a
--- memcpy(3).
+useAsCString (PS ps s l) = bracket alloc (c_free.castPtr)
+ where alloc = withForeignPtr ps $ \p -> do
+ buf <- c_malloc (fromIntegral l+1)
+ memcpy (castPtr buf) (castPtr p `plusPtr` s) (fromIntegral l)
+ poke (buf `plusPtr` l) (0::Word8) -- n.b.
+ return (castPtr buf)
+
+-- | /O(1) construction/ Use a @ByteString@ with a function requiring a @CStringLen@.
useAsCStringLen :: ByteString -> (CStringLen -> IO a) -> IO a
-useAsCStringLen (PS ps s l) = bracket alloc (c_free.castPtr.fst)
- where
- alloc = withForeignPtr ps $ \p -> do
- buf <- c_malloc (fromIntegral l+1)
- memcpy (castPtr buf) (castPtr p `plusPtr` s) (fromIntegral l)
- poke (buf `plusPtr` l) (0::Word8) -- n.b.
- return $! (castPtr buf, l)
+useAsCStringLen = unsafeUseAsCStringLen
+
+--
+-- why were we doing this?
+--
+-- useAsCStringLen :: ByteString -> (CStringLen -> IO a) -> IO a
+-- useAsCStringLen (PS ps s l) = bracket alloc (c_free.castPtr.fst)
+-- where
+-- alloc = withForeignPtr ps $ \p -> do
+-- buf <- c_malloc (fromIntegral l+1)
+-- memcpy (castPtr buf) (castPtr p `plusPtr` s) (fromIntegral l)
+-- poke (buf `plusPtr` l) (0::Word8) -- n.b.
+-- return $! (castPtr buf, l)
+--
-- | /O(n)/ Make a copy of the 'ByteString' with its own storage.
-- This is mainly useful to allow the rest of the data pointed
-- ---------------------------------------------------------------------
-- line IO
-#if defined(__GLASGOW_HASKELL__)
-
--- | getLine, read a line from stdin.
+-- | Read a line from stdin.
getLine :: IO ByteString
getLine = hGetLine stdin
+{-
-- | Lazily construct a list of lines of ByteStrings. This will be much
--- better on memory consumption than using lines =<< getContents.
+-- better on memory consumption than using 'hGetContents >>= lines'
+-- If you're considering this, a better choice might be to use
+-- Data.ByteString.Lazy
hGetLines :: Handle -> IO [ByteString]
hGetLines h = go
where
go = unsafeInterleaveIO $ do
- ms <- catch (hGetLine h >>= return . Just)
- (\_ -> return Nothing)
- case ms of
- Nothing -> return []
- Just s -> do ss <- go
- return (s:ss)
-
--- | hGetLine. read a ByteString from a handle
+ e <- hIsEOF h
+ if e
+ then return []
+ else do
+ x <- hGetLine h
+ xs <- go
+ return (x:xs)
+-}
+
+-- | Read a line from a handle
+
hGetLine :: Handle -> IO ByteString
+#if !defined(__GLASGOW_HASKELL__)
+hGetLine h = System.IO.hGetLine h >>= return . pack . P.map c2w
+#else
hGetLine h = wantReadableHandle "Data.ByteString.hGetLine" h $ \ handle_ -> do
case haBufferMode handle_ of
NoBuffering -> error "no buffering"
hGet _ 0 = return empty
hGet h i = createAndTrim i $ \p -> hGetBuf h p i
-#if defined(__GLASGOW_HASKELL__)
-- | hGetNonBlocking is identical to 'hGet', except that it will never block
-- waiting for data to become available, instead it returns only whatever data
-- is available.
hGetNonBlocking :: Handle -> Int -> IO ByteString
+#if defined(__GLASGOW_HASKELL__)
hGetNonBlocking _ 0 = return empty
hGetNonBlocking h i = createAndTrim i $ \p -> hGetBufNonBlocking h p i
+#else
+hGetNonBlocking = hGet
#endif
-- | Read entire handle contents into a 'ByteString'.
getContents :: IO ByteString
getContents = hGetContents stdin
+-- | The interact function takes a function of type @ByteString -> ByteString@
+-- as its argument. The entire input from the standard input device is passed
+-- to this function as its argument, and the resulting string is output on the
+-- standard output device. It's great for writing one line programs!
+interact :: (ByteString -> ByteString) -> IO ()
+interact transformer = putStr . transformer =<< getContents
+
-- | Read an entire file strictly into a 'ByteString'. This is far more
-- efficient than reading the characters into a 'String' and then using
-- 'pack'. It also may be more efficient than opening the file and
--- reading it using hGet.
+-- reading it using hGet. Files are read using 'binary mode' on Windows,
+-- for 'text mode' use the Char8 version of this function.
readFile :: FilePath -> IO ByteString
readFile f = bracket (openBinaryFile f ReadMode) hClose
(\h -> hFileSize h >>= hGet h . fromIntegral)
-- | Write a 'ByteString' to a file.
writeFile :: FilePath -> ByteString -> IO ()
-writeFile f ps = bracket (openBinaryFile f WriteMode) hClose
- (\h -> hPut h ps)
+writeFile f txt = bracket (openBinaryFile f WriteMode) hClose
+ (\h -> hPut h txt)
-- | Append a 'ByteString' to a file.
appendFile :: FilePath -> ByteString -> IO ()
appendFile f txt = bracket (openBinaryFile f AppendMode) hClose
- (\hdl -> hPut hdl txt)
+ (\h -> hPut h txt)
{-
--
#else
let unmap = return ()
#endif
- fp <- FC.newForeignPtr p unmap
+ fp <- newForeignPtr p unmap
return fp
c_close fd
hClose h
where mmap_limit = 16*1024
-}
-#if defined(__GLASGOW_HASKELL__)
---
--- | A ByteString equivalent for getArgs. More efficient for large argument lists
---
-getArgs :: IO [ByteString]
-getArgs =
- alloca $ \ p_argc ->
- alloca $ \ p_argv -> do
- getProgArgv p_argc p_argv
- p <- fromIntegral `fmap` peek p_argc
- argv <- peek p_argv
- P.map packCString `fmap` peekArray (p - 1) (advancePtr argv 1)
-#endif
-
-- ---------------------------------------------------------------------
-- Internal utilities
+-- | 'findIndexOrEnd' is a variant of findIndex, that returns the length
+-- of the string if no element is found, rather than Nothing.
+findIndexOrEnd :: (Word8 -> Bool) -> ByteString -> Int
+findIndexOrEnd k (PS x s l) = inlinePerformIO $ withForeignPtr x $ \f -> go (f `plusPtr` s) 0
+ where
+ STRICT2(go)
+ go ptr n | n >= l = return l
+ | otherwise = do w <- peek ptr
+ if k w
+ then return n
+ else go (ptr `plusPtr` 1) (n+1)
+{-# INLINE findIndexOrEnd #-}
+
-- | Perform an operation with a temporary ByteString
withPtr :: ForeignPtr a -> (Ptr a -> IO b) -> b
withPtr fp io = inlinePerformIO (withForeignPtr fp io)
{-# INLINE newForeignFreePtr #-}
newForeignFreePtr :: Ptr Word8 -> IO (ForeignPtr Word8)
-#if defined(__GLASGOW_HASKELL__)
-newForeignFreePtr p = FC.newForeignPtr p (c_free p)
-#else
newForeignFreePtr p = newForeignPtr c_free_finalizer p
-#endif
projects / haskell-directory.git / blobdiff