Ptr(..), nullPtr, writeCharOffPtr, plusAddr#,
BA(..), MBA(..),
packString, -- :: String -> (Int, BA)
- unpackCStringBA, -- :: BA -> Int -> [Char]
+ unpackNBytesBA, -- :: BA -> Int -> [Char]
strLength, -- :: Ptr CChar -> Int
copyPrefixStr, -- :: Addr# -> Int -> BA
copySubStr, -- :: Addr# -> Int -> Int -> BA
l@(I# length#) = length str
arr = runST (do
- ch_array <- new_ps_array (length# +# 1#)
+ ch_array <- new_ps_array length#
-- fill in packed string from "str"
fill_in ch_array 0# str
-- freeze the puppy:
fill_in :: MBA s -> Int# -> [Char] -> ST s ()
fill_in arr_in# idx [] =
- write_ps_array arr_in# idx (chr# 0#) >>
return ()
-
fill_in arr_in# idx (C# c : cs) =
write_ps_array arr_in# idx c >>
fill_in arr_in# (idx +# 1#) cs
Unpacking a string
\begin{code}
-unpackCStringBA :: BA -> Int -> [Char]
-unpackCStringBA (BA bytes) (I# len)
+unpackNBytesBA :: BA -> Int -> [Char]
+unpackNBytesBA (BA bytes) (I# len)
= unpack 0#
where
unpack nh
- | nh >=# len ||
- ch `eqChar#` '\0'# = []
- | otherwise = C# ch : unpack (nh +# 1#)
+ | nh >=# len = []
+ | otherwise = C# ch : unpack (nh +# 1#)
where
ch = indexCharArray# bytes nh
\end{code}
-Copying a char string prefix into a byte array,
-{\em assuming} the prefix does not contain any
-NULs.
+Copying a char string prefix into a byte array.
\begin{code}
copyPrefixStr :: Addr# -> Int -> BA
where
copy' length# = runST (do
{- allocate an array that will hold the string
- (not forgetting the NUL at the end)
-}
- ch_array <- new_ps_array (length# +# 1#)
+ ch_array <- new_ps_array length#
{- Revert back to Haskell-only solution for the moment.
_ccall_ memcpy ch_array (A# a) len >>= \ () ->
write_ps_array ch_array length# (chr# 0#) >>
fill_in :: MBA s -> Int# -> ST s ()
fill_in arr_in# idx
| idx ==# length#
- = write_ps_array arr_in# idx (chr# 0#) >>
- return ()
+ = return ()
| otherwise
= case (indexCharOffAddr# a# idx) of { ch ->
write_ps_array arr_in# idx ch >>
copySubStrBA (BA barr#) (I# start#) len@(I# length#) = ba
where
ba = runST (do
- {- allocate an array that will hold the string
- (not forgetting the NUL at the end)
- -}
- ch_array <- new_ps_array (length# +# 1#)
+ -- allocate an array that will hold the string
+ ch_array <- new_ps_array length#
-- fill in packed string from "addr"
fill_in ch_array 0#
-- freeze the puppy:
fill_in :: MBA s -> Int# -> ST s ()
fill_in arr_in# idx
| idx ==# length#
- = write_ps_array arr_in# idx (chr# 0#) >>
- return ()
+ = return ()
| otherwise
= case (indexCharArray# barr# (start# +# idx)) of { ch ->
write_ps_array arr_in# idx ch >>