Re: [boost] [serialization] bug in wide character strings

From: Robert Ramey (ramey_at_[hidden])
Date: 2008-04-17 17:30:30

OK- make a TRAK item out of this so I don't forget.

As a working around, you could tranform it to a vector of wchar
or using binary_object

Robert Ramey

Jeffrey Faust wrote:
> This test case only populates the wstring with lower case letters
> 'a'-'z'.  This does not seem to be a sufficient test for serializing
> wide strings.
>
> Jeff
>
> Robert Ramey wrote:
>> compare you application with test_simple_class.  This application
>> saves and restores
>> every data type suppported by the compiler/library/platform.  This
>> should include wstring.
>>
>> Robert Ramey
>>
>> Jeffrey Faust wrote:
>>
>>> We've discovered an issue Boost has writing and reading wide
>>> character strings (wchar_t* and std::wstrings) to non-wide
>>> character file streams (std::ifstream and std::ofstream).  The
>>> issue stems from the fact that
>>> wide characters are written and read as a sequence of characters (in
>>> text_oarchive_impl.ipp and text_iarchive_impl.ipp, respectively).
>>> For text streams, an EOF character terminates the reading of a file
>>> on Windows. Some wide characters have EOF (value = 26 decimal) as
>>> one of the bytes so reading that byte causes early termination of
>>> the read. We
>>> have worked around the issue by deriving our own input and output
>>> archives from text_i|oarchive_impl<Archive> and overriding
>>> load_override() and save_override for std::wstring and wchar_t*.
>>> Our implementation just sequences through the wide characters and
>>> writes them 1 by 1 as wchar_t to the archive.  This isn't very
>>> elegant and is even less readable in the file than the current
>>> implementation but does resolve the problem.
>>>
>>> I looked at both Boost 1.34.1 and 1.35 and didn't see a difference
>>> in the implementation here so I'm assuming 1.35 still has the issue.
>>> I've
>>> been working with 1.34.1.  Is this a known issue?  Does 1.35 solve
>>> it in
>>> some other subtle way?  Is there a better way that doesn't require
>>> us to derive our own streams?  If not, is there a more elegant way
>>> of implementing the reading and writing of wide characters
>>> ourselves?
>>>
>>> Thanks in advance.
>>>
>>> Jeff Faust
>>>
>>>
>
>
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