module Ptr.Peek
where
import Ptr.Prelude hiding (take)
import qualified Ptr.PokeAndPeek as B
import qualified Ptr.Parse as C
data Peek output =
Peek !Int !(Ptr Word8 -> IO output)
instance Functor Peek where
fmap fn (Peek size io) =
Peek size (fmap fn . io)
instance Applicative Peek where
pure x =
Peek 0 (const (pure x))
(<*>) (Peek leftSize leftIO) (Peek rightSize rightIO) =
Peek (leftSize + rightSize) io
where
io ptr =
leftIO ptr <*> rightIO (plusPtr ptr leftSize)
word8 :: Peek Word8
word8 =
pokeAndPeek B.word8
beWord16 :: Peek Word16
beWord16 =
pokeAndPeek B.beWord16
beWord32 :: Peek Word32
beWord32 =
pokeAndPeek B.beWord32
beWord64 :: Peek Word64
beWord64 =
pokeAndPeek B.beWord64
bytes :: Int -> Peek ByteString
bytes amount =
pokeAndPeek (B.bytes amount)
pokeAndPeek :: B.PokeAndPeek input output -> Peek output
pokeAndPeek (B.PokeAndPeek size _ io) =
Peek size io
parse :: Int -> C.Parse a -> (Int -> a) -> (Text -> a) -> Peek a
parse amount (C.Parse parseIO) eoi error =
Peek amount $ \ptr ->
parseIO amount ptr (return . eoi) (return . error) (\result _ _ -> return result)
peekAmountAndParse :: Peek Int -> C.Parse a -> (Int -> a) -> (Text -> a) -> Peek (Peek a)
peekAmountAndParse peekAmount parse_ eoi error =
flip fmap peekAmount $ \amount ->
parse amount parse_ eoi error