Hi Simon,
it looks that libc in OpenBSD 5.1 is not obeying to the documentation
for wcsrtombs/mbsrtowcs.
If_d__s__t_ is not a null pointer, the pointer object pointed to
by_s__r__c_ is assigned either a null pointer (if conversion
stopped due to reaching a terminating null wide-character)
or the address just past the last wide-character converted
(if any).
Instead of hacking the code to try to detect whether the conversion
actually wrote a NULL character in the converted string, I chose to
modify the 'configure' script to detect this behaviour and disable the
usage of the re-entrant functions if it doesn't match how the Xerces
code uses them.
Thank you for reporting this issue,
Alberto
Il 28/09/2012 00:18, Simon Elbaz ha scritto:
Hi,
I wanted to try using xerces on openbsd 5.1.
After compilation, DOMCount was always returning:
unknow reason.
After reading the code, it turns out that the end of conversion by
wcsrtombs and mbsrtowcs is based on a test on source pointer (source
pointer should point on null character).
The problem is that this behaviour is not implemented. Source pointer
points on the character following the last converted character leading
xerces binary to a risky memory access.
Below, there is a patch based on values returned by the functions (-1
in case of error, >= 0 in case of complete/incomplete conversion) that
fixes the problem.
Regards,
Simon Elbaz
$ svn diff xercesc/util/Transcoders/Iconv/IconvTransService.cpp
Index: xercesc/util/Transcoders/Iconv/IconvTransService.cpp
===================================================================
--- xercesc/util/Transcoders/Iconv/IconvTransService.cpp (revision
1387785)
+++ xercesc/util/Transcoders/Iconv/IconvTransService.cpp (working copy)
@@ -429,7 +429,7 @@
srcBuffer[gTempBuffArraySize - 1] = 0;
const wchar_t *src = 0;
- while (toTranscode[srcCursor] || src)
+ while (toTranscode[srcCursor])
{
if (src == 0) // copy a piece of the source string into a local
// buffer, converted to wchar_t and
NULL-terminated.
@@ -454,7 +454,7 @@
break;
}
dstCursor += len;
- if (src != 0) // conversion not finished. This *always* means
there
+ if (len == (resultSize - dstCursor)) // conversion not
finished. This *always* means there
// was not enough room in the destination buffer.
{
reallocString<char>(resultString, resultSize, manager,
resultString != localBuffer);
@@ -512,9 +512,9 @@
break;
}
dstCursor += len;
- if (src == 0) // conversion finished
+ if ((len >= 0) && (len < (resultSize - dstCursor))) //
conversion finished
break;
- if (dstCursor >= resultSize - 1)
+ if (len == (resultSize - dstCursor))
reallocString<wchar_t>(tmpString, resultSize, manager,
tmpString != localBuffer);
}
// make a final copy, converting from wchar_t to XMLCh:
