@@ -4,6 +4,7 @@
5-- Module : Data.Binary.Bits.Get
5-- Module : Data.Binary.Bits.Get
6-- Copyright : (c) Lennart Kolmodin 2010-2011
6-- Copyright : (c) Lennart Kolmodin 2010-2011
7+-- (c) Sylvain Henry 2015
7-- License : BSD3-style (see LICENSE)
8-- License : BSD3-style (see LICENSE)
9-- Maintainer : kolmodin@gmail.com
10-- Maintainer : kolmodin@gmail.com
@@ -59,7 +60,11 @@ module Data.Binary.Bits.Get
60 -- ** Get bytes
61 -- ** Get bytes
62 , getWord8
64 , getWord8
63 , getWord16be
68 , getWord16be
64 , getWord32be
69 , getWord32be
65 , getWord64be
70 , getWord64be
@@ -77,6 +82,9 @@ module Data.Binary.Bits.Get
77 -- ** Read in Blocks
82 -- ** Read in Blocks
80 , word16be
88 , word16be
81 , word32be
89 , word32be
82 , word64be
90 , word64be
@@ -87,25 +95,28 @@ module Data.Binary.Bits.Get
90−import Data.Binary.Get as B ( runGet, Get, getByteString, getLazyByteString, isEmpty )
98+import Data.Binary.Get as B ( Get, getLazyByteString, isEmpty )
91import Data.Binary.Get.Internal as B ( get, put, ensureN )
99import Data.Binary.Get.Internal as B ( get, put, ensureN )
100+import Data.Binary.Bits.BitOrder
101+import Data.Binary.Bits.Internal
102+import Data.Binary.Bits.Alignment
93import Data.ByteString as B
104import Data.ByteString as B
94import qualified Data.ByteString.Lazy as L
105import qualified Data.ByteString.Lazy as L
95import Data.ByteString.Unsafe
106import Data.ByteString.Unsafe
107+import Foreign.Marshal.Alloc (mallocBytes)
109+import Foreign.Storable (poke)
110+import System.IO.Unsafe (unsafePerformIO)
97import Data.Bits
112import Data.Bits
98import Data.Word
113import Data.Word
99import Control.Applicative
114import Control.Applicative
100−import Control.Monad (when)
115+import Control.Monad (when,foldM_)
102import Prelude as P
117import Prelude as P
104−#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
106import GHC.Word
118import GHC.Word
107−#endif
119+import GHC.Base (uncheckedShiftLWord8#, wordToWord8#, Int (..), andWord8#, Word8#, (-#), Int#, xorI#, eqWord8#, TYPE)
110-- $bitget
121-- $bitget
111-- Parse bits using a monad.
122-- Parse bits using a monad.
@@ -154,191 +165,120 @@ import GHC.Word
156data S = S {-# UNPACK #-} !ByteString -- Input
167data S = S {-# UNPACK #-} !ByteString -- Input
157− {-# UNPACK #-} !Int -- Bit offset (0-7)
168+ {-# UNPACK #-} !Int -- Bit offset (0-7)
169+ !BitOrder -- Bit order
158 deriving (Show)
170 deriving (Show)
160−-- | A block that will be read with only one boundry check. Needs to know the
172+-- | Increment the current bit offset
161−-- number of bits in advance.
162−data Block a = Block Int (S -> a)
164−instance Functor Block where
165− fmap f (Block i p) = Block i (\s -> f (p s))
167−instance Applicative Block where
168− pure a = Block 0 (\_ -> a)
169− (Block i p) <*> (Block j q) = Block (i+j) (\s -> p s $ q (incS i s))
170− (Block i _) *> (Block j q) = Block (i+j) (q . incS i)
171− (Block i p) <* (Block j _) = Block (i+j) p
173−-- | Get a block. Will be read with one single boundry check, and
174−-- therefore requires a statically known number of bits.
175−-- Build blocks using 'bool', 'word8', 'word16be', 'word32be', 'word64be',
176−-- 'byteString' and 'Applicative'.
177−block :: Block a -> BitGet a
178−block (Block i p) = do
181− putState $! (incS i s)
184incS :: Int -> S -> S
173incS :: Int -> S -> S
188− !n' = o' .&. make_mask 3
189− in S (unsafeDrop d bs) n'
174+incS o (S bs n bo) = S (unsafeDrop d bs) n' bo
191−-- | make_mask 3 = 00000111
176+ !o' = (n+o)
192−make_mask :: (Bits a, Num a) => Int -> a
193−make_mask n = (1 `shiftL` fromIntegral n) - 1
194−{-# SPECIALIZE make_mask :: Int -> Int #-}
195−{-# SPECIALIZE make_mask :: Int -> Word #-}
196−{-# SPECIALIZE make_mask :: Int -> Word8 #-}
197−{-# SPECIALIZE make_mask :: Int -> Word16 #-}
198−{-# SPECIALIZE make_mask :: Int -> Word32 #-}
199−{-# SPECIALIZE make_mask :: Int -> Word64 #-}
201−bit_offset :: Int -> Int
202−bit_offset n = make_mask 3 .&. n
204−byte_offset :: Int -> Int
177+ !d = byte_offset o'
205−byte_offset n = n `shiftR` 3
178+ !n' = bit_offset o'
180+-- | Read a single bit
207readBool :: S -> Bool
181readBool :: S -> Bool
182+readBool (S bs o bo) = case bo of
183+ BB -> testBit (unsafeHead bs) (7-o)
208−readBool (S bs n) = testBit (unsafeHead bs) (7-n)
184+ BL -> testBit (unsafeHead bs) (7-o)
209−
185+ LL -> testBit (unsafeHead bs) o
210−{-# INLINE readWord8 #-}
186+ LB -> testBit (unsafeHead bs) o
211−readWord8 :: Int -> S -> Word8
187+
212−readWord8 n (S bs o)
188+-- | Read a single bit
213− -- no bits at all, return 0
189+readBool# :: S -> Int
214− | n == 0 = 0
190+readBool# (S bs (I# o) bo) = case bo of
215−
191+ BB -> testBit# (7# -# o)
216− -- all bits are in the same byte
192+ BL -> testBit# (7# -# o)
217− -- we just need to shift and mask them right
193+ LL -> testBit# o
218− | n <= 8 - o = let w = unsafeHead bs
194+ LB -> testBit# o
219− m = make_mask n
195+ where
220− w' = (w `shiftr_w8` (8 - o - n)) .&. m
196+ !(W8# w) = unsafeHead bs
221− in w'
197+ testBit# n = I# (((w `andWord8#` (wordToWord8# 1## `uncheckedShiftLWord8#` n)) `eqWord8#` wordToWord8# 0##) `xorI#` 1#)
223− -- the bits are in two different bytes
199+
224− -- make a word16 using both bytes, and then shift and mask
200+-- | Extract a range of bits from (ws :: ByteString)
225− | n <= 8 = let w = (fromIntegral (unsafeHead bs) `shiftl_w16` 8) .|.
201+--
226− (fromIntegral (unsafeIndex bs 1))
202+-- Constraint: 8 * (length ws -1 ) < o+n <= 8 * length ws
227− m = make_mask n
203+extract :: (Num a, FastBits a) => BitOrder -> ByteString -> Int -> Int -> a
228− w' = (w `shiftr_w16` (16 - o - n)) .&. m
204+extract bo bs o n
229− in fromIntegral w'
205+ | n == 0 = 0
230−
206+ | B.length bs == 0 = error "Empty ByteString"
231−{-# INLINE readWord16be #-}
207+ | otherwise = rev . mask n . foldlWithIndex' f 0 $ bs
232−readWord16be :: Int -> S -> Word16
208+ where
233−readWord16be n s@(S bs o)
209+ -- B.foldl' with index
234−
210+ foldlWithIndex' op b = fst . B.foldl' g (b,0)
235− -- 8 or fewer bits, use readWord8
211+ where g (b',i) w = (op b' w i, (i+1))
236− | n <= 8 = fromIntegral (readWord8 n s)
212+
237−
213+ -- 'or' correctly shifted words
238− -- handle 9 or more bits, stored in two bytes
214+ f b w i = b .|. (fromIntegral w `fastShift` off i)
240− -- no offset, plain and simple 16 bytes
216+ -- co-offset
241− | o == 0 && n == 16 = let msb = fromIntegral (unsafeHead bs)
217+ r = B.length bs * 8 - (o + n)
242− lsb = fromIntegral (unsafeIndex bs 1)
218+
243− w = (msb `shiftl_w16` 8) .|. lsb
219+ -- shift offset depending on the byte position (0..B.length-1)
244− in w
220+ off i = case bo of
246− -- no offset, but not full 16 bytes
222+ LB -> 8*i - o
247− | o == 0 = let msb = fromIntegral (unsafeHead bs)
223+ BB -> (B.length bs -1 - i) * 8 - r
248− lsb = fromIntegral (unsafeIndex bs 1)
224+ BL -> (B.length bs -1 - i) * 8 - r
249− w = (msb `shiftl_w16` (n-8)) .|. (lsb `shiftr_w16` (16-n))
225+
250− in w
226+ -- reverse bits if necessary
251−
227+ rev = case bo of
252− -- with offset, and n=9-16
228+ LB -> reverseBits n
253− | n <= 16 = readWithOffset s shiftl_w16 shiftr_w16 n
229+ BL -> reverseBits n
255− | otherwise = error "readWord16be: tried to read more than 16 bits"
231+ LL -> id
257−{-# INLINE readWord32be #-}
233+
258−readWord32be :: Int -> S -> Word32
234+-- | Generic readWord
259−readWord32be n s@(S _ o)
235+readWord :: (Num a, FastBits a) => Int -> S -> a
260− -- 8 or fewer bits, use readWord8
236+readWord n (S bs o bo)
261− | n <= 8 = fromIntegral (readWord8 n s)
237+ | n == 0 = 0
262−
238+ | otherwise = extract bo (unsafeTake nbytes bs) o n
263− -- 16 or fewer bits, use readWord16be
239+ where nbytes = byte_offset (o+n+7)
264− | n <= 16 = fromIntegral (readWord16be n s)
240+
265−
241+-- | Check that the number of bits to read is not greater than the first parameter
266− | o == 0 = readWithoutOffset s shiftl_w32 shiftr_w32 n
242+{-# INLINE readWordChecked #-}
267−
243+readWordChecked :: (Num a, FastBits a) => Int -> Int -> S -> a
268− | n <= 32 = readWithOffset s shiftl_w32 shiftr_w32 n
244+readWordChecked m n s
270− | otherwise = error "readWord32be: tried to read more than 32 bits"
245+ | n > m = error $ "Tried to read more than " ++ show m ++ " bits (" ++ show n ++")"
271−
246+ | otherwise = readWord n s
273−{-# INLINE readWord64be #-}
248+-- | Read the given number of bytes and return them in Big-Endian order
274−readWord64be :: Int -> S -> Word64
249+--
275−readWord64be n s@(S _ o)
250+-- Examples:
276− -- 8 or fewer bits, use readWord8
251+-- BB: xxxABCDE FGHIJKLM NOPxxxxx -> ABCDEFGH IJKLMNOP
277− | n <= 8 = fromIntegral (readWord8 n s)
252+-- LL: LMNOPxxx DEFGHIJK xxxxxABC -> ABCDEFGH IJKLMNOP
278−
253+-- BL: xxxPONML KJIHGFED CBAxxxxx -> ABCDEFGH IJKLMNOP
279− -- 16 or fewer bits, use readWord16be
254+-- LB: EDCBAxxx MLKJIHGF xxxxxPON -> ABCDEFGH IJKLMNOP
280− | n <= 16 = fromIntegral (readWord16be n s)
282− | o == 0 = readWithoutOffset s shiftl_w64 shiftr_w64 n
284− | n <= 64 = readWithOffset s shiftl_w64 shiftr_w64 n
286− | otherwise = error "readWord64be: tried to read more than 64 bits"
289readByteString :: Int -> S -> ByteString
255readByteString :: Int -> S -> ByteString
290−readByteString n s@(S bs o)
256+readByteString n (S bs o bo) =
291− -- no offset, easy.
257+ let
292− | o == 0 = unsafeTake n bs
258+ bs' = unsafeTake (n+1) bs
293− -- offset. ugg. this is really naive and slow. but also pretty easy :)
259+ bs'' = unsafeTake n bs
294− | otherwise = B.pack (P.map (readWord8 8) (P.take n (iterate (incS 8) s)))
260+ rev = B.map (reverseBits 8)
295−
261+ in case (o,bo) of
296−readWithoutOffset :: (Bits a, Num a)
262+ (0,BB) -> bs''
297− => S -> (a -> Int -> a) -> (a -> Int -> a) -> Int -> a
263+ (0,LL) -> B.reverse bs''
298−readWithoutOffset (S bs o) shifterL shifterR n
264+ (0,LB) -> rev bs''
299− | o /= 0 = error "readWithoutOffset: there is an offset"
265+ (0,BL) -> rev . B.reverse $ bs''
300−
266+ (_,LL) -> readByteString n (S (B.reverse bs') (8-o) BB)
301− | bit_offset n == 0 && byte_offset n <= 4 =
267+ (_,BL) -> rev . B.reverse $ readByteString n (S bs' o BB)
302− let segs = byte_offset n
268+ (_,LB) -> rev . B.reverse $ readByteString n (S bs' o LL)
303− bn 0 = fromIntegral (unsafeHead bs)
269+ (_,BB) -> unsafePerformIO $ do
304− bn n = (bn (n-1) `shifterL` 8) .|. fromIntegral (unsafeIndex bs n)
270+ let len = n+1
305−
271+ ptr <- mallocBytes len
306− in bn (segs-1)
272+ let f r i = do
308− | n <= 64 = let segs = byte_offset n
274+ w = unsafeIndex bs (len-i)
309− o' = bit_offset (n - 8 + o)
275+ w' = (w `fastShiftL` o) .|. r
310−
276+ r' = w `fastShiftR` (8-o)
311− bn 0 = fromIntegral (unsafeHead bs)
277+ poke (ptr `plusPtr` (len-i)) w'
312− bn n = (bn (n-1) `shifterL` 8) .|. fromIntegral (unsafeIndex bs n)
278+ return r'
313−
279+ foldM_ f 0 [1..len]
314− msegs = bn (segs-1) `shifterL` o'
280+ unsafeInit <$> unsafePackMallocCStringLen (ptr,len)
316− last = (fromIntegral (unsafeIndex bs segs)) `shifterR` (8 - o')
321−readWithOffset :: (Bits a, Num a)
322− => S -> (a -> Int -> a) -> (a -> Int -> a) -> Int -> a
323−readWithOffset (S bs o) shifterL shifterR n
324− | n <= 64 = let bits_in_msb = 8 - o
325− (n',top) = (n - bits_in_msb
326− , (fromIntegral (unsafeHead bs) .&. make_mask bits_in_msb) `shifterL` n')
328− segs = byte_offset n'
331− bn n = (bn (n-1) `shifterL` 8) .|. fromIntegral (unsafeIndex bs n)
335− mseg = bn segs `shifterL` o'
337− last | o' > 0 = (fromIntegral (unsafeIndex bs (segs + 1))) `shifterR` (8 - o')
340− w = top .|. mseg .|. last
343------------------------------------------------------------------------
283------------------------------------------------------------------------
344-- | 'BitGet' is a monad, applicative and a functor. See 'runBitGet'
284-- | 'BitGet' is a monad, applicative and a functor. See 'runBitGet'
@@ -347,7 +287,6 @@ newtype BitGet a = B { runState :: S -> Get (S,a) }
348instance Monad BitGet where
288instance Monad BitGet where
349 return x = B $ \s -> return (s,x)
289 return x = B $ \s -> return (s,x)
350− fail str = B $ \(S inp n) -> putBackState inp n >> fail str
351 (B f) >>= g = B $ \s -> do (s',a) <- f s
290 (B f) >>= g = B $ \s -> do (s',a) <- f s
352 runState (g a) s'
291 runState (g a) s'
@@ -358,25 +297,51 @@ instance Applicative BitGet where
358 pure x = return x
297 pure x = return x
359 fm <*> m = fm >>= \f -> m >>= \v -> return (f v)
298 fm <*> m = fm >>= \f -> m >>= \v -> return (f v)
300+instance BitOrderable BitGet where
302+ (S bs o _) <- getState
303+ putState (S bs o bo)
306+ (S _ _ bo) <- getState
309+instance Alignable BitGet where
310+ -- | Skip the given number of bits
315+ -- | Skip bits if necessary to align to the next byte
317+ (S _ o _) <- getState
361-- | Run a 'BitGet' within the Binary packages 'Get' monad. If a byte has
323-- | Run a 'BitGet' within the Binary packages 'Get' monad. If a byte has
362-- been partially consumed it will be discarded once 'runBitGet' is finished.
324-- been partially consumed it will be discarded once 'runBitGet' is finished.
363runBitGet :: BitGet a -> Get a
325runBitGet :: BitGet a -> Get a
364runBitGet bg = do
326runBitGet bg = do
365 s <- mkInitState
327 s <- mkInitState
366− ((S str' n),a) <- runState bg s
328+ (s',a) <- runState bg s
367− putBackState str' n
329+ putBackState s'
370mkInitState :: Get S
332mkInitState :: Get S
371mkInitState = do
333mkInitState = do
372− str <- get
334+ bs <- get
373 put B.empty
335 put B.empty
374− return (S str 0)
336+ return (S bs 0 BB)
376−putBackState :: B.ByteString -> Int -> Get ()
338+putBackState :: S -> Get ()
377−putBackState bs n = do
339+putBackState (S bs o _) = do
378 remaining <- get
340 remaining <- get
343+ _ -> unsafeDrop 1 bs
379− put (B.drop (if n==0 then 0 else 1) bs `B.append` remaining)
344+ put (bs' `B.append` remaining)
381getState :: BitGet S
346getState :: BitGet S
382getState = B $ \s -> return (s,s)
347getState = B $ \s -> return (s,s)
@@ -384,52 +349,66 @@ getState = B $ \s -> return (s,s)
384putState :: S -> BitGet ()
349putState :: S -> BitGet ()
385putState s = B $ \_ -> return (s,())
350putState s = B $ \_ -> return (s,())
352+withState :: (S -> S) -> BitGet ()
387-- | Make sure there are at least @n@ bits.
357-- | Make sure there are at least @n@ bits.
388ensureBits :: Int -> BitGet ()
358ensureBits :: Int -> BitGet ()
389ensureBits n = do
359ensureBits n = do
390− (S bs o) <- getState
360+ (S bs o bo) <- getState
391 if n <= (B.length bs * 8 - o)
361 if n <= (B.length bs * 8 - o)
392 then return ()
362 then return ()
393 else do let currentBits = B.length bs * 8 - o
363 else do let currentBits = B.length bs * 8 - o
394− let byteCount = (n - currentBits + 7) `div` 8
364+ let byteCount = byte_offset (n - currentBits + 7)
395 B $ \_ -> do B.ensureN byteCount
365 B $ \_ -> do B.ensureN byteCount
396 bs' <- B.get
366 bs' <- B.get
397 put B.empty
367 put B.empty
398− return (S (bs`append`bs') o, ())
368+ return (S (bs`append`bs') o bo, ())
400−-- | Skip the given number of bits
401−skipBits :: Int -> BitGet ()
405− putState $! (incS n s)
407−-- | Skip bits if necessary to align on a byte
370+-- | Test whether all input has been consumed, i.e. there are no remaining
408−alignByte :: BitGet ()
371+-- undecoded bytes.
409−alignByte = do
372+isEmpty :: BitGet Bool
410− (S _ n) <- getState
373+isEmpty = B $ \ (S bs o bo) -> if B.null bs
411− when (n /= 0) $
374+ then B.isEmpty >>= \e -> return (S bs o bo, e)
412− skipBits (8-n)
375+ else return (S bs o bo, False)
414-- | Get 1 bit as a 'Bool'.
377-- | Get 1 bit as a 'Bool'.
415getBool :: BitGet Bool
378getBool :: BitGet Bool
416getBool = block bool
379getBool = block bool
381+-- | Get 1 bit as a 'Bool'.
382+getBool# :: BitGet Int
383+getBool# = block bool#
418-- | Get @n@ bits as a 'Word8'. @n@ must be within @[0..8]@.
385-- | Get @n@ bits as a 'Word8'. @n@ must be within @[0..8]@.
419getWord8 :: Int -> BitGet Word8
386getWord8 :: Int -> BitGet Word8
420getWord8 n = block (word8 n)
387getWord8 n = block (word8 n)
422-- | Get @n@ bits as a 'Word16'. @n@ must be within @[0..16]@.
389-- | Get @n@ bits as a 'Word16'. @n@ must be within @[0..16]@.
390+getWord16 :: Int -> BitGet Word16
391+getWord16 n = block (word16 n)
423getWord16be :: Int -> BitGet Word16
393getWord16be :: Int -> BitGet Word16
424−getWord16be n = block (word16be n)
394+getWord16be = getWord16
395+{-# DEPRECATED getWord16be "Use 'getWord16' instead" #-}
426-- | Get @n@ bits as a 'Word32'. @n@ must be within @[0..32]@.
397-- | Get @n@ bits as a 'Word32'. @n@ must be within @[0..32]@.
398+getWord32 :: Int -> BitGet Word32
399+getWord32 n = block (word32 n)
427getWord32be :: Int -> BitGet Word32
401getWord32be :: Int -> BitGet Word32
428−getWord32be n = block (word32be n)
402+getWord32be = getWord32
403+{-# DEPRECATED getWord32be "Use 'getWord32' instead" #-}
430-- | Get @n@ bits as a 'Word64'. @n@ must be within @[0..64]@.
405-- | Get @n@ bits as a 'Word64'. @n@ must be within @[0..64]@.
406+getWord64 :: Int -> BitGet Word64
407+getWord64 n = block (word64 n)
431getWord64be :: Int -> BitGet Word64
409getWord64be :: Int -> BitGet Word64
432−getWord64be n = block (word64be n)
410+getWord64be = getWord64
411+{-# DEPRECATED getWord64be "Use 'getWord64' instead" #-}
434-- | Get @n@ bytes as a 'ByteString'.
413-- | Get @n@ bytes as a 'ByteString'.
435getByteString :: Int -> BitGet ByteString
414getByteString :: Int -> BitGet ByteString
@@ -438,88 +417,80 @@ getByteString n = block (byteString n)
438-- | Get @n@ bytes as a lazy ByteString.
417-- | Get @n@ bytes as a lazy ByteString.
439getLazyByteString :: Int -> BitGet L.ByteString
418getLazyByteString :: Int -> BitGet L.ByteString
440getLazyByteString n = do
419getLazyByteString n = do
441− (S _ o) <- getState
420+ (S _ o bo) <- getState
442 case o of
421 case o of
443− 0 -> B $ \ (S bs o') -> do
422+ 0 -> B $ \s -> do
444− putBackState bs o'
423+ putBackState s
445 lbs <- B.getLazyByteString (fromIntegral n)
424 lbs <- B.getLazyByteString (fromIntegral n)
446− return (S B.empty 0, lbs)
425+ return (S B.empty 0 bo, lbs)
447 _ -> L.fromChunks . (:[]) <$> Data.Binary.Bits.Get.getByteString n
426 _ -> L.fromChunks . (:[]) <$> Data.Binary.Bits.Get.getByteString n
449−-- | Test whether all input has been consumed, i.e. there are no remaining
428+
450−-- undecoded bytes.
429+
451−isEmpty :: BitGet Bool
430+
452−isEmpty = B $ \ (S bs o) -> if B.null bs
431+
453− then B.isEmpty >>= \e -> return (S bs o, e)
432+-- | A block that will be read with only one boundary check. Needs to know the
433+-- number of bits in advance.
434+data Block a = Block Int (S -> a)
436+instance Functor Block where
437+ fmap f (Block i p) = Block i (\s -> f (p s))
439+instance Applicative Block where
440+ pure a = Block 0 (\_ -> a)
441+ (Block i p) <*> (Block j q) = Block (i+j) (\s -> p s $ q (incS i s))
442+ (Block i _) *> (Block j q) = Block (i+j) (q . incS i)
443+ (Block i p) <* (Block j _) = Block (i+j) p
445+-- | Get a block. Will be read with one single boundry check, and
446+-- therefore requires a statically known number of bits.
447+-- Build blocks using 'bool', 'word8', 'word16be', 'word32be', 'word64be',
448+-- 'byteString' and 'Applicative'.
449+block :: Block a -> BitGet a
450+block (Block i p) = do
453+ putState $! (incS i s)
454− else return (S bs o, False)
454+ return $! p s
456-- | Read a 1 bit 'Bool'.
456-- | Read a 1 bit 'Bool'.
457bool :: Block Bool
457bool :: Block Bool
458bool = Block 1 readBool
458bool = Block 1 readBool
460+-- | Read a 1 bit 'Bool'.
462+bool# = Block 1 readBool#
460-- | Read @n@ bits as a 'Word8'. @n@ must be within @[0..8]@.
464-- | Read @n@ bits as a 'Word8'. @n@ must be within @[0..8]@.
461word8 :: Int -> Block Word8
465word8 :: Int -> Block Word8
462−word8 n = Block n (readWord8 n)
466+word8 n = Block n (readWordChecked 8 n)
464-- | Read @n@ bits as a 'Word16'. @n@ must be within @[0..16]@.
468-- | Read @n@ bits as a 'Word16'. @n@ must be within @[0..16]@.
469+word16 :: Int -> Block Word16
470+word16 n = Block n (readWordChecked 16 n)
465word16be :: Int -> Block Word16
472word16be :: Int -> Block Word16
466−word16be n = Block n (readWord16be n)
473+word16be = word16
474+{-# DEPRECATED word16be "Use 'word16' instead" #-}
468-- | Read @n@ bits as a 'Word32'. @n@ must be within @[0..32]@.
476-- | Read @n@ bits as a 'Word32'. @n@ must be within @[0..32]@.
477+word32 :: Int -> Block Word32
478+word32 n = Block n (readWordChecked 32 n)
469word32be :: Int -> Block Word32
480word32be :: Int -> Block Word32
470−word32be n = Block n (readWord32be n)
481+word32be = word32
482+{-# DEPRECATED word32be "Use 'word32' instead" #-}
472-- | Read @n@ bits as a 'Word64'. @n@ must be within @[0..64]@.
484-- | Read @n@ bits as a 'Word64'. @n@ must be within @[0..64]@.
485+word64 :: Int -> Block Word64
486+word64 n = Block n (readWordChecked 64 n)
473word64be :: Int -> Block Word64
488word64be :: Int -> Block Word64
474−word64be n = Block n (readWord64be n)
489+word64be = word64
490+{-# DEPRECATED word64be "Use 'word64' instead" #-}
476-- | Read @n@ bytes as a 'ByteString'.
492-- | Read @n@ bytes as a 'ByteString'.
477byteString :: Int -> Block ByteString
493byteString :: Int -> Block ByteString
478byteString n | n > 0 = Block (n*8) (readByteString n)
494byteString n | n > 0 = Block (n*8) (readByteString n)
479 | otherwise = Block 0 (\_ -> B.empty)
495 | otherwise = Block 0 (\_ -> B.empty)
481−------------------------------------------------------------------------
482−-- Unchecked shifts, from the package binary
484−shiftl_w16 :: Word16 -> Int -> Word16
485−shiftl_w32 :: Word32 -> Int -> Word32
486−shiftl_w64 :: Word64 -> Int -> Word64
488−#if defined(__GLASGOW_HASKELL__) && !defined(__HADDOCK__)
489−shiftl_w8 (W8# w) (I# i) = W8# (w `uncheckedShiftL#` i)
490−shiftl_w16 (W16# w) (I# i) = W16# (w `uncheckedShiftL#` i)
491−shiftl_w32 (W32# w) (I# i) = W32# (w `uncheckedShiftL#` i)
493−shiftr_w8 (W8# w) (I# i) = W8# (w `uncheckedShiftRL#` i)
494−shiftr_w16 (W16# w) (I# i) = W16# (w `uncheckedShiftRL#` i)
495−shiftr_w32 (W32# w) (I# i) = W32# (w `uncheckedShiftRL#` i)
498−#if WORD_SIZE_IN_BITS < 64
499−shiftl_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftL64#` i)
500−shiftr_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftRL64#` i)
502−#if __GLASGOW_HASKELL__ <= 606
503−-- Exported by GHC.Word in GHC 6.8 and higher
504−foreign import ccall unsafe "stg_uncheckedShiftL64"
505− uncheckedShiftL64# :: Word64# -> Int# -> Word64#
506−foreign import ccall unsafe "stg_uncheckedShiftRL64"
507− uncheckedShiftRL64# :: Word64# -> Int# -> Word64#
511−shiftl_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftL#` i)
512−shiftr_w64 (W64# w) (I# i) = W64# (w `uncheckedShiftRL#` i)