module FileBytes where

import Data.Word (Word8)
import Foreign.Marshal.Array (allocaArray, peekArray, pokeArray)
import System.IO (hFileSize, Handle, hGetBuf, hPutBuf, openBinaryFile, hClose,
                  IOMode(ReadMode, WriteMode))

-- ----------------------------------------------------------------------
-- supporting utf-8 stuff
-- ----------------------------------------------------------------------

readFileBytes :: FilePath -> IO [Word8]
readFileBytes f =
  do h <- openBinaryFile f ReadMode
     hsize <- fromIntegral `fmap` hFileSize h
     hGetBytes h hsize

writeFileBytes :: FilePath -> [Word8] -> IO ()
writeFileBytes f ws =
 do h <- openBinaryFile f WriteMode
    hPutBytes h (length ws) ws
    hClose h

hGetBytes :: Handle -> Int -> IO [Word8]
hGetBytes h c = allocaArray c $ \p ->
                  do c' <- hGetBuf h p c
                     peekArray c' p

hPutBytes :: Handle -> Int -> [Word8] -> IO ()
hPutBytes h c ws = allocaArray c $ \p ->
                     do pokeArray p ws
                        hPutBuf h p c