module Util.UTF8(
toUTF8,
fromUTF8WE,
) where
import Data.Char
import Data.List
import Data.Bits
import Data.Word
import Control.Monad.Except ()
import Control.Monad.Fail
import Util.Computation
toUTF8 :: Enum byte => String -> [byte]
toUTF8 :: String -> [byte]
toUTF8 [] = []
toUTF8 (Char
x:String
xs) =
let
xs1 :: [byte]
xs1 = String -> [byte]
forall byte. Enum byte => String -> [byte]
toUTF8 String
xs
ox :: Int
ox = Char -> Int
ord Char
x
mkUTF8 :: Int -> [a] -> Int -> Int -> [a]
mkUTF8 Int
x0 [a]
xs0 Int
xmask0 Int
xmax0 =
let
xbot :: Int
xbot = Int
0x80 Int -> Int -> Int
forall a. Bits a => a -> a -> a
.|. (Int
x0 Int -> Int -> Int
forall a. Bits a => a -> a -> a
.&. Int
0x3f)
x1 :: Int
x1 = Int
x0 Int -> Int -> Int
forall a. Bits a => a -> Int -> a
`shiftR` Int
6
xs1 :: [a]
xs1 = Int -> a
forall a. Enum a => Int -> a
toEnum Int
xbot a -> [a] -> [a]
forall a. a -> [a] -> [a]
: [a]
xs0
in
if Int
x1 Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
< Int
xmax0
then
Int -> a
forall a. Enum a => Int -> a
toEnum (Int
xmask0 Int -> Int -> Int
forall a. Bits a => a -> a -> a
.|. Int
x1) a -> [a] -> [a]
forall a. a -> [a] -> [a]
: [a]
xs1
else
let
xmask1 :: Int
xmask1 = Int
xmask0 Int -> Int -> Int
forall a. Bits a => a -> a -> a
.|. Int
xmax0
xmax1 :: Int
xmax1 = Int
xmax0 Int -> Int -> Int
forall a. Bits a => a -> Int -> a
`shiftR` Int
1
in
Int -> [a] -> Int -> Int -> [a]
mkUTF8 Int
x1 [a]
xs1 Int
xmask1 Int
xmax1
in
if Int
ox Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
<= Int
0x7f
then
Int -> byte
forall a. Enum a => Int -> a
toEnum Int
ox byte -> [byte] -> [byte]
forall a. a -> [a] -> [a]
: [byte]
xs1
else
if Int
ox Int -> Int -> Int
forall a. Bits a => a -> Int -> a
`shiftR` Int
31 Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
/= Int
0
then
String -> [byte]
forall a. HasCallStack => String -> a
error (String
"Huge character with code " String -> String -> String
forall a. [a] -> [a] -> [a]
++ Int -> String
forall a. Show a => a -> String
show Int
ox String -> String -> String
forall a. [a] -> [a] -> [a]
++
String
" detected in string being converted to UTF8.")
else
Int -> [byte] -> Int -> Int -> [byte]
forall a. Enum a => Int -> [a] -> Int -> Int -> [a]
mkUTF8 Int
ox [byte]
xs1 Int
0xc0 Int
0x20
{-# SPECIALIZE toUTF8 :: String -> [Char] #-}
{-# SPECIALIZE toUTF8 :: String -> [Word8] #-}
fromUTF8WE :: (Enum byte,MonadFail m) => [byte] -> m String
fromUTF8WE :: [byte] -> m String
fromUTF8WE [] = String -> m String
forall (m :: * -> *) a. Monad m => a -> m a
return []
fromUTF8WE (byte
x0 : [byte]
xs0) =
let
ox :: Int
ox = byte -> Int
forall a. Enum a => a -> Int
fromEnum byte
x0
in
case Int -> Int
topZero8 Int
ox of
Int
7 ->
do
String
xs1 <- [byte] -> m String
forall byte (m :: * -> *).
(Enum byte, MonadFail m) =>
[byte] -> m String
fromUTF8WE [byte]
xs0
String -> m String
forall (m :: * -> *) a. Monad m => a -> m a
return (Int -> Char
chr Int
ox Char -> String -> String
forall a. a -> [a] -> [a]
: String
xs1)
Int
6 ->
String -> m String
forall (m :: * -> *) a. MonadFail m => String -> m a
Control.Monad.Fail.fail String
"UTF8 escape sequence starts 10xxxxxx"
Int
0 ->
String -> m String
forall (m :: * -> *) a. MonadFail m => String -> m a
Control.Monad.Fail.fail String
"UTF8 escape sequence starts 11111110"
-1 ->
String -> m String
forall (m :: * -> *) a. MonadFail m => String -> m a
Control.Monad.Fail.fail String
"UTF8 escape sequence starts 11111111"
Int
n ->
let
r :: Int
r = Int
6 Int -> Int -> Int
forall a. Num a => a -> a -> a
- Int
n
xtop :: Int
xtop = Int
ox Int -> Int -> Int
forall a. Bits a => a -> a -> a
.&. Int -> Int
ones Int
n
minx :: Int
minx =
Int -> Int
forall a. Bits a => Int -> a
bit (
if Int
r Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
== Int
1
then
Int
7
else
Int
5Int -> Int -> Int
forall a. Num a => a -> a -> a
*Int
r Int -> Int -> Int
forall a. Num a => a -> a -> a
+ Int
1
)
mkx :: [a] -> Int -> t -> m (Int, [a])
mkx [] Int
_ t
_ =
String -> m (Int, [a])
forall (m :: * -> *) a. MonadFail m => String -> m a
Control.Monad.Fail.fail String
"UTF8 string ends in middle of escape sequence"
mkx (a
ch : [a]
xs1) Int
x0 t
count0 =
do
let
och :: Int
och = a -> Int
forall a. Enum a => a -> Int
fromEnum a
ch
if Int
och Int -> Int -> Int
forall a. Bits a => a -> a -> a
.&. Int
0x80 Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
/= Int
0x80
then
String -> m ()
forall (m :: * -> *) a. MonadFail m => String -> m a
Control.Monad.Fail.fail (String
"UTF8 escape sequence contains continuing "
String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"character not of form 10xxxxxx")
else
() -> m ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
let
xbot :: Int
xbot = Int
och Int -> Int -> Int
forall a. Bits a => a -> a -> a
.&. Int
0x3f
x1 :: Int
x1 = (Int
x0 Int -> Int -> Int
forall a. Bits a => a -> Int -> a
`shiftL` Int
6) Int -> Int -> Int
forall a. Bits a => a -> a -> a
.|. Int
xbot
count1 :: t
count1 = t
count0 t -> t -> t
forall a. Num a => a -> a -> a
- t
1
if t
count1 t -> t -> Bool
forall a. Eq a => a -> a -> Bool
== t
0
then
(Int, [a]) -> m (Int, [a])
forall (m :: * -> *) a. Monad m => a -> m a
return (Int
x1,[a]
xs1)
else
[a] -> Int -> t -> m (Int, [a])
mkx [a]
xs1 Int
x1 t
count1
in
do
(Int
x,[byte]
xs1) <- [byte] -> Int -> Int -> m (Int, [byte])
forall (m :: * -> *) t a.
(MonadFail m, Eq t, Enum a, Num t) =>
[a] -> Int -> t -> m (Int, [a])
mkx [byte]
xs0 Int
xtop Int
r
if Int
x Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
< Int
minx
then
String -> m String
forall (m :: * -> *) a. MonadFail m => String -> m a
Control.Monad.Fail.fail (String
"UTF8 escape sequence contains character not "
String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"optimally encoded")
else
do
String
xs2 <- [byte] -> m String
forall byte (m :: * -> *).
(Enum byte, MonadFail m) =>
[byte] -> m String
fromUTF8WE [byte]
xs1
String -> m String
forall (m :: * -> *) a. Monad m => a -> m a
return (Int -> Char
forall a. Enum a => Int -> a
toEnum Int
x Char -> String -> String
forall a. a -> [a] -> [a]
: String
xs2)
{-# SPECIALIZE fromUTF8WE :: String -> WithError String #-}
{-# SPECIALIZE fromUTF8WE :: [Word8] -> WithError String #-}
topZero8 :: Int -> Int
topZero8 :: Int -> Int
topZero8 Int
i =
case
((Bool -> Bool) -> [Bool] -> Maybe Int
forall a. (a -> Bool) -> [a] -> Maybe Int
findIndex Bool -> Bool
not
((Int -> Bool) -> [Int] -> [Bool]
forall a b. (a -> b) -> [a] -> [b]
map
(\ Int
bn -> Int -> Int -> Bool
forall a. Bits a => a -> Int -> Bool
testBit Int
i Int
bn)
[Int
7,Int
6..Int
0]
))
of
Just Int
n -> Int
7 Int -> Int -> Int
forall a. Num a => a -> a -> a
- Int
n
Maybe Int
Nothing -> -Int
1
ones :: Int -> Int
ones :: Int -> Int
ones Int
i = Int -> Int
forall a. Bits a => Int -> a
bit Int
i Int -> Int -> Int
forall a. Num a => a -> a -> a
- Int
1