ref: ea5ce18495d0eb7fdc4589130d1a55c42febac06
dir: /lib/System/IO.hs/
-- Copyright 2023,2024 Lennart Augustsson
-- See LICENSE file for full license.
module System.IO(
IO, Handle, FilePath,
IOMode(..),
stdin, stdout, stderr,
hGetChar, hPutChar,
hLookAhead,
putChar, getChar,
hClose, hFlush,
openFile, openFileM, openBinaryFile,
hPutStr, hPutStrLn,
putStr, putStrLn,
print,
hGetContents, getContents,
hGetLine, getLine,
interact,
writeFile, readFile, appendFile,
cprint, cuprint,
mkTextEncoding, hSetEncoding, utf8,
openTmpFile, openTempFile,
withFile,
) where
import Prelude() -- do not import Prelude
import Primitives
import Control.Applicative
import Control.Error
import Control.Monad
import Control.Monad.Fail
import Data.Bool
import Data.Char
import Data.Eq
import Data.Function
import Data.Functor
import Data.Int
import Data.List
import Data.Maybe
import Data.Num
import Data.String
import Data.Tuple
import Text.Show
import Foreign.C.String
import Foreign.Marshal.Alloc
import Foreign.Ptr
import System.IO.Unsafe
import System.IO_Handle
data FILE
primHPrint :: forall a . Ptr BFILE -> a -> IO ()
primHPrint = primitive "IO.print"
primStdin :: Ptr BFILE
primStdin = primitive "IO.stdin"
primStdout :: Ptr BFILE
primStdout = primitive "IO.stdout"
primStderr :: Ptr BFILE
primStderr = primitive "IO.stderr"
foreign import ccall "fopen" c_fopen :: CString -> CString -> IO (Ptr FILE)
foreign import ccall "closeb" c_closeb :: Ptr BFILE -> IO ()
foreign import ccall "flushb" c_flushb :: Ptr BFILE -> IO ()
foreign import ccall "getb" c_getb :: Ptr BFILE -> IO Int
foreign import ccall "ungetb" c_ungetb :: Int -> Ptr BFILE -> IO ()
foreign import ccall "putb" c_putb :: Int -> Ptr BFILE -> IO ()
foreign import ccall "add_FILE" c_add_FILE :: Ptr FILE -> IO (Ptr BFILE)
foreign import ccall "add_utf8" c_add_utf8 :: Ptr BFILE -> IO (Ptr BFILE)
----------------------------------------------------------
instance Eq Handle where
Handle p == Handle q = p == q
instance Show Handle where
show (Handle p) = "Handle-" ++ show p
type FilePath = String
data IOMode = ReadMode | WriteMode | AppendMode | ReadWriteMode
instance Functor IO where
fmap f ioa = ioa `primBind` \ a -> primReturn (f a)
instance Applicative IO where
pure = primReturn
(<*>) = ap
instance Monad IO where
(>>=) = primBind
(>>) = primThen
return = primReturn
instance MonadFail IO where
fail = error
stdin :: Handle
stdin = Handle primStdin
stdout :: Handle
stdout = Handle primStdout
stderr :: Handle
stderr = Handle primStderr
--bFILE :: Ptr FILE -> Handle
--bFILE = Handle . primPerformIO . (c_add_utf8 <=< c_add_FILE)
hClose :: Handle -> IO ()
hClose (Handle p) = c_closeb p
hFlush :: Handle -> IO ()
hFlush (Handle p) = c_flushb p
hGetChar :: Handle -> IO Char
hGetChar (Handle p) = do
c <- c_getb p
if c == (-1::Int) then
error "hGetChar: EOF"
else
return (chr c)
hLookAhead :: Handle -> IO Char
hLookAhead h@(Handle p) = do
c <- hGetChar h
c_ungetb (ord c) p
return c
hPutChar :: Handle -> Char -> IO ()
hPutChar (Handle p) c = c_putb (ord c) p
openFILEM :: FilePath -> IOMode -> IO (Maybe (Ptr FILE))
openFILEM p m = do
let
ms = case m of
ReadMode -> "r"
WriteMode -> "w"
AppendMode -> "a"
ReadWriteMode -> "w+"
h <- withCAString p $ \cp -> withCAString ms $ \ cm -> c_fopen cp cm
if h == nullPtr then
return Nothing
else
return (Just h)
openFileM :: FilePath -> IOMode -> IO (Maybe Handle)
openFileM p m = do
mf <- openFILEM p m
case mf of
Nothing -> return Nothing
Just p -> do { q <- c_add_utf8 =<< c_add_FILE p; return (Just (Handle q)) }
openFile :: String -> IOMode -> IO Handle
openFile p m = do
mh <- openFileM p m
case mh of
Nothing -> error ("openFile: cannot open " ++ p)
Just h -> return h
putChar :: Char -> IO ()
putChar = hPutChar stdout
getChar :: IO Char
getChar = hGetChar stdin
cprint :: forall a . a -> IO ()
cprint a = primRnfNoErr a `seq` primHPrint p a
where Handle p = stdout
cuprint :: forall a . a -> IO ()
cuprint = primHPrint p
where Handle p = stdout
print :: forall a . (Show a) => a -> IO ()
print a = putStrLn (show a)
putStr :: String -> IO ()
putStr = hPutStr stdout
hPutStr :: Handle -> String -> IO ()
hPutStr h = mapM_ (hPutChar h)
putStrLn :: String -> IO ()
putStrLn = hPutStrLn stdout
hPutStrLn :: Handle -> String -> IO ()
hPutStrLn h s = hPutStr h s >> hPutChar h '\n'
hGetLine :: Handle -> IO String
hGetLine h = loop ""
where loop s = do
c <- hGetChar h
if c == '\n' then
return (reverse s)
else
loop (c:s)
getLine :: IO String
getLine = hGetLine stdin
writeFile :: FilePath -> String -> IO ()
writeFile p s = do
h <- openFile p WriteMode
hPutStr h s
hClose h
appendFile :: FilePath -> String -> IO ()
appendFile p s = do
h <- openFile p AppendMode
hPutStr h s
hClose h
{-
-- Faster, but uses a lot more C memory.
writeFileFast :: FilePath -> String -> IO ()
writeFileFast p s = do
h <- openFile p WriteMode
(cs, l) <- newCAStringLen s
n <- c_fwrite cs 1 l h
free cs
hClose h
when (l /= n) $
error "writeFileFast failed"
-}
-- Lazy readFile
readFile :: FilePath -> IO String
readFile p = do
h <- openFile p ReadMode
cs <- hGetContents h
--hClose h can't close with lazy hGetContents
return cs
-- Lazy hGetContents
hGetContents :: Handle -> IO String
hGetContents h@(Handle p) = do
c <- c_getb p
if c == (-1::Int) then do
hClose h -- EOF, so close the handle
return ""
else do
cs <- unsafeInterleaveIO (hGetContents h)
return (chr c : cs)
getContents :: IO String
getContents = hGetContents stdin
interact :: (String -> String) -> IO ()
interact f = getContents >>= putStr . f
openBinaryFile :: String -> IOMode -> IO Handle
openBinaryFile p m = do
mf <- openFILEM p m
case mf of
Nothing -> error $ "openBinaryFile: cannot open " ++ show p
Just p -> do { q <- c_add_FILE p; return (Handle q) }
--------
-- For compatibility
data TextEncoding = UTF8
utf8 :: TextEncoding
utf8 = UTF8
mkTextEncoding :: String -> IO TextEncoding
mkTextEncoding "UTF-8//ROUNDTRIP" = return UTF8
mkTextEncoding _ = error "unknown text encoding"
-- Always in UTF8 mode
hSetEncoding :: Handle -> TextEncoding -> IO ()
hSetEncoding _ _ = return ()
--------
-- XXX needs bracket
withFile :: forall r . FilePath -> IOMode -> (Handle -> IO r) -> IO r
withFile fn md io = do
h <- openFile fn md
r <- io h
hClose h
return r
--------
splitTmp :: String -> (String, String)
splitTmp tmpl =
case span (/= '.') (reverse tmpl) of
(rsuf, "") -> (tmpl, "")
(rsuf, _:rpre) -> (reverse rpre, '.':reverse rsuf)
-- Create a temporary file, take a prefix and a suffix
-- and returns a malloc()ed string.
foreign import ccall "tmpname" c_tmpname :: CString -> CString -> IO CString
-- Create and open a temporary file.
openTmpFile :: String -> IO (String, Handle)
openTmpFile tmpl = do
let (pre, suf) = splitTmp tmpl
ctmp <- withCAString pre $ withCAString suf . c_tmpname
tmp <- peekCAString ctmp
free ctmp
h <- openFile tmp ReadWriteMode
return (tmp, h)
-- Sloppy implementation of openTempFile
openTempFile :: FilePath -> String -> IO (String, Handle)
openTempFile tmp tmplt = do
let (pre, suf) = splitTmp tmplt
loop n = do
let fn = tmp ++ "/" ++ pre ++ show n ++ suf
mh <- openFileM fn ReadMode
case mh of
Just h -> do
hClose h
loop (n+1 :: Int)
Nothing -> do
h <- openFile fn ReadWriteMode
return (fn, h)
loop 0