module IPv4Text1 where import Net.Types (IPv4(..)) import Data.Text (Text) import Data.Monoid ((<>)) import Data.Text.Internal (Text(..)) import Data.Word import Data.ByteString (ByteString) import Control.Monad.ST import Data.Bits (shiftR,(.&.)) import qualified Data.ByteString.Char8 as BC8 import qualified Data.ByteString as ByteString import qualified Data.ByteString.Unsafe as ByteString import qualified Data.Text.Array as TArray ------------------------ -- This implementation operates directly on -- a mutable array. It is the fastest one so far. -- On a 2012 laptop, it can serialize an IPv4 -- address to Text in 35ns. It is somewhat wasteful -- of space. It allocates a full 30 bytes in case it -- needs it, but it may need as few as 14 bytes. ------------------------ encode :: IPv4 -> Text encode (IPv4 w) = let w1 = fromIntegral $ 255 .&. shiftR w 24 w2 = fromIntegral $ 255 .&. shiftR w 16 w3 = fromIntegral $ 255 .&. shiftR w 8 w4 = fromIntegral $ 255 .&. w (arr,len) = runST $ do marr <- TArray.new 15 i1 <- putAndCount 0 w1 marr let n1 = i1 n1' = i1 + 1 TArray.unsafeWrite marr n1 dot i2 <- putAndCount n1' w2 marr let n2 = i2 + n1' n2' = n2 + 1 TArray.unsafeWrite marr n2 dot i3 <- putAndCount n2' w3 marr let n3 = i3 + n2' n3' = n3 + 1 TArray.unsafeWrite marr n3 dot i4 <- putAndCount n3' w4 marr theArr <- TArray.unsafeFreeze marr return (theArr,i4 + n3') in Text arr 0 len putAndCount :: Int -> Word8 -> TArray.MArray s -> ST s Int putAndCount pos w marr | w < 10 = TArray.unsafeWrite marr pos (i2w w) >> return 1 | w < 100 = write2 pos w >> return 2 | otherwise = write3 pos w >> return 3 where write2 off i0 = do let i = fromIntegral i0; j = i + i TArray.unsafeWrite marr off $ get2 j TArray.unsafeWrite marr (off + 1) $ get2 (j + 1) write3 off i0 = do let i = fromIntegral i0; j = i + i + i TArray.unsafeWrite marr off $ get3 j TArray.unsafeWrite marr (off + 1) $ get3 (j + 1) TArray.unsafeWrite marr (off + 2) $ get3 (j + 2) get2 = fromIntegral . ByteString.unsafeIndex twoDigits get3 = fromIntegral . ByteString.unsafeIndex threeDigits zero,dot :: Word16 zero = 48 {-# INLINE zero #-} dot = 46 {-# INLINE dot #-} i2w :: (Integral a) => a -> Word16 i2w v = zero + fromIntegral v {-# INLINE i2w #-} twoDigits :: ByteString twoDigits = BC8.pack "0001020304050607080910111213141516171819\ \2021222324252627282930313233343536373839\ \4041424344454647484950515253545556575859\ \6061626364656667686970717273747576777879\ \8081828384858687888990919293949596979899" threeDigits :: ByteString threeDigits = ByteString.replicate 300 0 <> BC8.pack "100101102103104105106107108109110111112\ \113114115116117118119120121122123124125\ \126127128129130131132133134135136137138\ \139140141142143144145146147148149150151\ \152153154155156157158159160161162163164\ \165166167168169170171172173174175176177\ \178179180181182183184185186187188189190\ \191192193194195196197198199200201202203\ \204205206207208209210211212213214215216\ \217218219220221222223224225226227228229\ \230231232233234235236237238239240241242\ \243244245246247248249250251252253254255"