Buffers for scanning string input stored in external arrays.
\begin{code}
+#include "HsVersions.h"
+
module StringBuffer
(
StringBuffer,
) where
import Ubiq
+#if __GLASGOW_HASKELL__ <= 200
import PreludeGlaST
import PreludeGlaMisc
+#else
+import GlaExts
+import Foreign
+import IOBase
+import IOHandle
+import ST
+import STBase
+import Char (isDigit)
+#endif
import PrimPacked
import FastString
import HandleHack
-- Allocate an array for system call to store its bytes into.
-- ToDo: make it robust
-- _trace (show (len_i::Int)+1)
- (_casm_ `` %r=(char *)malloc(sizeof(char)*(int)%0); '' (len_i::Int)) `thenPrimIO` \ arr@(A# a#) ->
+ (_casm_ `` %r=(char *)malloc(sizeof(char)*(int)%0); '' (len_i::Int)) `CCALL_THEN` \ arr@(A# a#) ->
if addr2Int# a# ==# 0# then
- failWith (UserError ("hGetStringBuffer: Could not allocate "++show len_i ++ " bytes"))
+ failWith MkIOError(hndl,UserError,("hGetStringBuffer: Could not allocate "++show len_i ++ " bytes"))
else
-- _casm_ `` %r=NULL; '' `thenPrimIO` \ free_p ->
-- makeForeignObj arr free_p `thenPrimIO` \ fo@(_ForeignObj fo#) ->
- _readHandle hndl >>= \ _hndl ->
- _writeHandle hndl _hndl >>
- let ptr = _filePtr _hndl in
- _ccall_ fread arr (1::Int) len_i ptr `thenPrimIO` \ (I# read#) ->
+ _readHandle hndl >>= \ hndl_ ->
+ _writeHandle hndl hndl_ >>
+ let ptr = _filePtr hndl_ in
+ _ccall_ fread arr (1::Int) len_i ptr `CCALL_THEN` \ (I# read#) ->
-- _trace ("DEBUG: opened " ++ fname ++ show (I# read#)) $
hClose hndl >>
if read# ==# 0# then -- EOF or other error
- failWith (UserError "hGetStringBuffer: EOF reached or some other error")
+ failWith MkIOError(hndl,UserError,"hGetStringBuffer: EOF reached or some other error")
else
-- Add a sentinel NUL
- _casm_ `` ((char *)%0)[(int)%1]=(char)0; '' arr (I# (read# -# 1#)) `thenPrimIO` \ () ->
+ _casm_ `` ((char *)%0)[(int)%1]=(char)0; '' arr (I# (read# -# 1#)) `CCALL_THEN` \ () ->
return (StringBuffer a# read# 0# 0#)
freeStringBuffer :: StringBuffer -> IO ()
freeStringBuffer (StringBuffer a# _ _ _) =
- _casm_ `` free((char *)%0); '' (A# a#) `thenPrimIO` \ () ->
+ _casm_ `` free((char *)%0); '' (A# a#) `CCALL_THEN` \ () ->
return ()
unsafeWriteBuffer :: StringBuffer -> Int# -> Char# -> StringBuffer
case indexCharOffAddr# fo c# of
'\"'# ->
case indexCharOffAddr# fo (c# -# 1#) of
- '\\'# -> --escaped, false alarm.
- loop (c# +# 1#)
+ '\\'# ->
+ -- looks like an escaped something or other to me,
+ -- better count the number of "\\"s that are immediately
+ -- preceeding to decide if the " is escaped.
+ let
+ odd_slashes flg i# =
+ case indexCharOffAddr# fo i# of
+ '\\'# -> odd_slashes (not flg) (i# -# 1#)
+ _ -> flg
+ in
+ if odd_slashes True (c# -# 1#) then
+ -- odd number, " is ecaped.
+ loop (c# +# 1#)
+ else -- a real end of string delimiter after all.
+ StringBuffer fo l# s# c#
_ -> StringBuffer fo l# s# c#
_ -> loop (c# +# 1#)
case indexCharOffAddr# fo c# of
'\''# ->
case indexCharOffAddr# fo (c# -# 1#) of
- '\\'# -> --escaped, false alarm.
- loop (c# +# 1#)
+ '\\'# ->
+ case indexCharOffAddr# fo (c# -# 2#) of
+ '\\'# -> -- end of char
+ StringBuffer fo l# s# c#
+ _ -> loop (c# +# 1#) -- false alarm
_ -> StringBuffer fo l# s# c#
_ -> loop (c# +# 1#)