{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE MagicHash #-}
module Data.ByteString.Base16.Internal.Utils
( aix
, w32
, w64
, writeNPlainForeignPtrBytes
) where

import Foreign.ForeignPtr
import Foreign.Ptr
import Foreign.Storable

import GHC.Exts
import GHC.ForeignPtr
import GHC.Word

import System.IO.Unsafe

-- | Read 'Word8' index off alphabet addr
--
aix :: Word8 -> Addr# -> Word8
aix :: Word8 -> Addr# -> Word8
aix (W8# i :: Word#
i) alpha :: Addr#
alpha = Word# -> Word8
W8# (Addr# -> Int# -> Word#
indexWord8OffAddr# Addr#
alpha (Word# -> Int#
word2Int# Word#
i))
{-# INLINE aix #-}

w32 :: Word8 -> Word32
w32 :: Word8 -> Word32
w32 = Word8 -> Word32
forall a b. (Integral a, Num b) => a -> b
fromIntegral
{-# INLINE w32 #-}

w64 :: Word8 -> Word64
w64 :: Word8 -> Word64
w64 = Word8 -> Word64
forall a b. (Integral a, Num b) => a -> b
fromIntegral
{-# INLINE w64 #-}

-- | Allocate and fill @n@ bytes with some data
--
writeNPlainForeignPtrBytes
    :: ( Storable a
       , Storable b
       )
    => Int
    -> [a]
    -> ForeignPtr b
writeNPlainForeignPtrBytes :: Int -> [a] -> ForeignPtr b
writeNPlainForeignPtrBytes !Int
n as :: [a]
as = IO (ForeignPtr b) -> ForeignPtr b
forall a. IO a -> a
unsafeDupablePerformIO (IO (ForeignPtr b) -> ForeignPtr b)
-> IO (ForeignPtr b) -> ForeignPtr b
forall a b. (a -> b) -> a -> b
$ do
    ForeignPtr a
fp <- Int -> IO (ForeignPtr a)
forall a. Int -> IO (ForeignPtr a)
mallocPlainForeignPtrBytes Int
n
    ForeignPtr a -> (Ptr a -> IO ()) -> IO ()
forall a b. ForeignPtr a -> (Ptr a -> IO b) -> IO b
withForeignPtr ForeignPtr a
fp ((Ptr a -> IO ()) -> IO ()) -> (Ptr a -> IO ()) -> IO ()
forall a b. (a -> b) -> a -> b
$ \p :: Ptr a
p -> Ptr a -> [a] -> IO ()
forall b. Storable b => Ptr b -> [b] -> IO ()
go Ptr a
p [a]
as
    ForeignPtr b -> IO (ForeignPtr b)
forall (m :: * -> *) a. Monad m => a -> m a
return (ForeignPtr a -> ForeignPtr b
forall a b. ForeignPtr a -> ForeignPtr b
castForeignPtr ForeignPtr a
fp)
  where
    go :: Ptr b -> [b] -> IO ()
go !Ptr b
_ [] = () -> IO ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
    go !Ptr b
p (x :: b
x:xs :: [b]
xs) = Ptr b -> b -> IO ()
forall a. Storable a => Ptr a -> a -> IO ()
poke Ptr b
p b
x IO () -> IO () -> IO ()
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> Ptr b -> [b] -> IO ()
go (Ptr b -> Int -> Ptr b
forall a b. Ptr a -> Int -> Ptr b
plusPtr Ptr b
p 1) [b]
xs