On 17 September 2018 at 05:48, José Guilherme Vanz via Boost-users < boost-users@lists.boost.org> wrote:
Hi guys,
I'm investigating a bug https://github.com/scylladb/scylla/issues/2905 in the Seastar/lexical_cast and I got stuck. Let me introduce what's going on and the further investigation that I did. The Seastar framework uses the boost program options to parse the command line arguments. But when the user try to pass a command line argument of seastar::sstring (Seastar string type) with a white space, the lib tells us that is invalid value.
Turns out the boost program options call lexical_cast to cast from std::string to seastar::sstring. This cast is failing. The lexical_cast uses a stream to extract the value from the source, but the operator>> stops in the white space. Making the second validation in the same line https://github.com/boostorg/lexical_cast/blob/boost-1.66.0/include/boost/lex... false. Note, there is a call https://github.com/boostorg/lexical_cast/blob/boost-1.66.0/include/boost/lex... to unsetf to ensure that the white space will be skipped: stream.unsetf(std::ios::skipws);.
What's am I trying to do is figure out where the problems live? Is there a bug in boost or is a sstring implemantion problem? Am I missing something?
Overload validate, cf the documentation https://www.boost.org/doc/libs/1_68_0/doc/html/program_options/howto.html#id...