{-# LANGUAGE
TemplateHaskell, MultiParamTypeClasses, GADTs
#-}
module Data.Random.Source.DevRandom
( DevRandom(..)
) where
import Data.Random.Source
import Foreign.Marshal (allocaBytes)
import Foreign.Ptr (castPtr)
import Foreign.Storable (peek)
import System.IO (openBinaryFile, hGetBuf, Handle, IOMode(..))
import System.IO.Unsafe (unsafePerformIO)
data DevRandom = DevRandom | DevURandom
deriving (DevRandom -> DevRandom -> Bool
(DevRandom -> DevRandom -> Bool)
-> (DevRandom -> DevRandom -> Bool) -> Eq DevRandom
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: DevRandom -> DevRandom -> Bool
$c/= :: DevRandom -> DevRandom -> Bool
== :: DevRandom -> DevRandom -> Bool
$c== :: DevRandom -> DevRandom -> Bool
Eq, Int -> DevRandom -> ShowS
[DevRandom] -> ShowS
DevRandom -> String
(Int -> DevRandom -> ShowS)
-> (DevRandom -> String)
-> ([DevRandom] -> ShowS)
-> Show DevRandom
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [DevRandom] -> ShowS
$cshowList :: [DevRandom] -> ShowS
show :: DevRandom -> String
$cshow :: DevRandom -> String
showsPrec :: Int -> DevRandom -> ShowS
$cshowsPrec :: Int -> DevRandom -> ShowS
Show)
{-# NOINLINE devRandom #-}
devRandom :: Handle
devRandom :: Handle
devRandom = IO Handle -> Handle
forall a. IO a -> a
unsafePerformIO (String -> IOMode -> IO Handle
openBinaryFile String
"/dev/random" IOMode
ReadMode)
{-# NOINLINE devURandom #-}
devURandom :: Handle
devURandom :: Handle
devURandom = IO Handle -> Handle
forall a. IO a -> a
unsafePerformIO (String -> IOMode -> IO Handle
openBinaryFile String
"/dev/urandom" IOMode
ReadMode)
dev :: DevRandom -> Handle
dev :: DevRandom -> Handle
dev DevRandom
DevRandom = Handle
devRandom
dev DevRandom
DevURandom = Handle
devURandom
$(randomSource
[d| instance RandomSource IO DevRandom where
getRandomWord8From src = allocaBytes 1 $ \buf -> do
1 <- hGetBuf (dev src) buf 1
peek buf
getRandomWord16From src = allocaBytes 2 $ \buf -> do
2 <- hGetBuf (dev src) buf 2
peek (castPtr buf)
getRandomWord32From src = allocaBytes 4 $ \buf -> do
4 <- hGetBuf (dev src) buf 4
peek (castPtr buf)
getRandomWord64From src = allocaBytes 8 $ \buf -> do
8 <- hGetBuf (dev src) buf 8
peek (castPtr buf)
|])