module Codec.Utils (
Octet,
msb,
fromTwosComp, toTwosComp,
toOctets, fromOctets,
listFromOctets, listToOctets,
i2osp
) where
import Data.Word
import Data.Bits
powersOf :: t -> [t]
powersOf t
n = t
1 forall a. a -> [a] -> [a]
: (forall a b. (a -> b) -> [a] -> [b]
map (forall a. Num a => a -> a -> a
*t
n) (t -> [t]
powersOf t
n))
toBase :: b -> b -> [b]
toBase b
x =
forall a b. (a -> b) -> [a] -> [b]
map forall a b. (Integral a, Num b) => a -> b
fromIntegral forall b c a. (b -> c) -> (a -> b) -> a -> c
.
forall a. [a] -> [a]
reverse forall b c a. (b -> c) -> (a -> b) -> a -> c
.
forall a b. (a -> b) -> [a] -> [b]
map (forall a b c. (a -> b -> c) -> b -> a -> c
flip forall a. Integral a => a -> a -> a
mod b
x) forall b c a. (b -> c) -> (a -> b) -> a -> c
.
forall a. (a -> Bool) -> [a] -> [a]
takeWhile (forall a. Eq a => a -> a -> Bool
/=b
0) forall b c a. (b -> c) -> (a -> b) -> a -> c
.
forall a. (a -> a) -> a -> [a]
iterate (forall a b c. (a -> b -> c) -> b -> a -> c
flip forall a. Integral a => a -> a -> a
div b
x)
toOctets :: (Integral a, Integral b) => a -> b -> [Octet]
toOctets :: forall a b. (Integral a, Integral b) => a -> b -> [Octet]
toOctets a
n b
x = (forall {b} {b}. (Integral b, Num b) => b -> b -> [b]
toBase a
n forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. (Integral a, Num b) => a -> b
fromIntegral) b
x
trimNulls :: [Word8] -> [Word8]
trimNulls :: [Octet] -> [Octet]
trimNulls = forall a. [a] -> [a]
reverse forall b c a. (b -> c) -> (a -> b) -> a -> c
. (forall a. (a -> Bool) -> [a] -> [a]
dropWhile (forall a. Eq a => a -> a -> Bool
== Octet
0)) forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a. [a] -> [a]
reverse
listToOctets :: (Bits a, Integral a) => [a] -> [Octet]
listToOctets :: forall a. (Bits a, Integral a) => [a] -> [Octet]
listToOctets [a]
x = [Octet] -> [Octet]
trimNulls forall a b. (a -> b) -> a -> b
$ forall (t :: * -> *) a. Foldable t => t [a] -> [a]
concat [[Octet]]
paddedOctets where
paddedOctets :: [[Octet]]
paddedOctets :: [[Octet]]
paddedOctets = forall a b. (a -> b) -> [a] -> [b]
map (Int -> [Octet] -> [Octet]
padTo Int
bytes) [[Octet]]
rawOctets
rawOctets :: [[Octet]]
rawOctets :: [[Octet]]
rawOctets = forall a b. (a -> b) -> [a] -> [b]
map (forall a. [a] -> [a]
reverse forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. (Integral a, Integral b) => a -> b -> [Octet]
toOctets Integer
256) [a]
x
padTo :: Int -> [Octet] -> [Octet]
padTo :: Int -> [Octet] -> [Octet]
padTo Int
x [Octet]
y = forall a. Int -> [a] -> [a]
take Int
x forall a b. (a -> b) -> a -> b
$ [Octet]
y forall a. [a] -> [a] -> [a]
++ forall a. a -> [a]
repeat Octet
0
bytes :: Int
bytes :: Int
bytes = forall a. Bits a => a -> Int
bitSize (forall a. [a] -> a
head [a]
x) forall a. Integral a => a -> a -> a
`div` Int
8
type Octet = Word8
msb :: Int
msb :: Int
msb = forall a. Bits a => a -> Int
bitSize (forall a. HasCallStack => a
undefined::Octet) forall a. Num a => a -> a -> a
- Int
1
fromOctets :: (Integral a, Integral b) => a -> [Octet] -> b
fromOctets :: forall a b. (Integral a, Integral b) => a -> [Octet] -> b
fromOctets a
n [Octet]
x =
forall a b. (Integral a, Num b) => a -> b
fromIntegral forall a b. (a -> b) -> a -> b
$
forall (t :: * -> *) a. (Foldable t, Num a) => t a -> a
sum forall a b. (a -> b) -> a -> b
$
forall a b c. (a -> b -> c) -> [a] -> [b] -> [c]
zipWith forall a. Num a => a -> a -> a
(*) (forall {t}. Num t => t -> [t]
powersOf a
n) (forall a. [a] -> [a]
reverse (forall a b. (a -> b) -> [a] -> [b]
map forall a b. (Integral a, Num b) => a -> b
fromIntegral [Octet]
x))
listFromOctets :: (Integral a, Bits a) => [Octet] -> [a]
listFromOctets :: forall a. (Integral a, Bits a) => [Octet] -> [a]
listFromOctets [] = []
listFromOctets [Octet]
x = [a]
result where
result :: [a]
result = a
first forall a. a -> [a] -> [a]
: [a]
rest
first :: a
first = forall a b. (Integral a, Integral b) => a -> [Octet] -> b
fromOctets Integer
256 [Octet]
first'
first' :: [Octet]
first' = forall a. [a] -> [a]
reverse forall a b. (a -> b) -> a -> b
$ forall a. Int -> [a] -> [a]
take Int
bytes [Octet]
x
rest :: [a]
rest = forall a. (Integral a, Bits a) => [Octet] -> [a]
listFromOctets forall a b. (a -> b) -> a -> b
$ forall a. Int -> [a] -> [a]
drop Int
bytes [Octet]
x
bytes :: Int
bytes = forall a. Bits a => a -> Int
bitSize a
first forall a. Integral a => a -> a -> a
`div` Int
8
i2osp :: Integral a => Int -> a -> [Octet]
i2osp :: forall a. Integral a => Int -> a -> [Octet]
i2osp Int
l a
y =
[Octet]
pad forall a. [a] -> [a] -> [a]
++ [Octet]
z
where
pad :: [Octet]
pad = forall a. Int -> a -> [a]
replicate (Int
l forall a. Num a => a -> a -> a
- Int
unPaddedLen) (Octet
0x00::Octet)
z :: [Octet]
z = forall a b. (Integral a, Integral b) => a -> b -> [Octet]
toOctets Integer
256 a
y
unPaddedLen :: Int
unPaddedLen = forall (t :: * -> *) a. Foldable t => t a -> Int
length [Octet]
z
fromTwosComp :: Integral a => [Octet] -> a
fromTwosComp :: forall a. Integral a => [Octet] -> a
fromTwosComp [Octet]
x = forall {a}. Num a => [Octet] -> a
conv [Octet]
x
where conv :: [Octet] -> a
conv [] = a
0
conv w :: [Octet]
w@(Octet
x:[Octet]
xs) = if (forall a. Bits a => a -> Int -> Bool
testBit Octet
x Int
msb)
then forall {a}. Num a => [Octet] -> a
neg [Octet]
w
else forall {a}. Num a => [Octet] -> a
pos [Octet]
w
neg :: [Octet] -> b
neg w :: [Octet]
w@(Octet
x:[Octet]
xs) = let z :: [Octet]
z=(forall a. Bits a => a -> Int -> a
clearBit Octet
x Int
msb)forall a. a -> [a] -> [a]
:[Octet]
xs in
forall a b. (Integral a, Num b) => a -> b
fromIntegral((forall a b. (Integral a, Integral b) => a -> [Octet] -> b
fromOctets Integer
256 [Octet]
z)forall a. Num a => a -> a -> a
-
(Integer
128forall a. Num a => a -> a -> a
*(Integer
256forall a b. (Num a, Integral b) => a -> b -> a
^((forall (t :: * -> *) a. Foldable t => t a -> Int
length [Octet]
w)forall a. Num a => a -> a -> a
-Int
1))))
pos :: [Octet] -> b
pos [Octet]
w = forall a b. (Integral a, Num b) => a -> b
fromIntegral(forall a b. (Integral a, Integral b) => a -> [Octet] -> b
fromOctets Integer
256 [Octet]
w)
toTwosComp :: Integral a => a -> [Octet]
toTwosComp :: forall a. Integral a => a -> [Octet]
toTwosComp a
x
| a
x forall a. Ord a => a -> a -> Bool
< a
0 = forall a. [a] -> [a]
reverse forall b c a. (b -> c) -> (a -> b) -> a -> c
. [Octet] -> [Octet]
plusOne forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a. [a] -> [a]
reverse forall b c a. (b -> c) -> (a -> b) -> a -> c
. (forall a b. (a -> b) -> [a] -> [b]
map forall a. Bits a => a -> a
complement) forall a b. (a -> b) -> a -> b
$ [Octet]
u
| a
x forall a. Eq a => a -> a -> Bool
== a
0 = [Octet
0x00]
| Bool
otherwise = [Octet]
u
where z :: [Octet]
z@(Octet
y:[Octet]
ys) = forall {b} {b}. (Integral b, Num b) => b -> b -> [b]
toBase a
256 (forall a. Num a => a -> a
abs a
x)
u :: [Octet]
u = if forall a. Bits a => a -> Int -> Bool
testBit Octet
y Int
msb
then Octet
0x00forall a. a -> [a] -> [a]
:[Octet]
z
else [Octet]
z
plusOne :: [Octet] -> [Octet]
plusOne :: [Octet] -> [Octet]
plusOne [] = [Octet
1]
plusOne (Octet
x:[Octet]
xs) =
if Octet
x forall a. Eq a => a -> a -> Bool
== Octet
0xff
then Octet
0x00forall a. a -> [a] -> [a]
:([Octet] -> [Octet]
plusOne [Octet]
xs)
else (Octet
xforall a. Num a => a -> a -> a
+Octet
1)forall a. a -> [a] -> [a]
:[Octet]
xs