[Boost-users] [iostreams] : bug in <boost/iostreams/copy.hpp> ?

From: Mathieu Peyréga (mathieu.peyrega_at_[hidden])
Date: 2006-12-09 13:53:31

Hello,

i'm a new user to these great boost libraries...
I think i found a bug in <boost/iostreams/copy.hpp> (version 1.33.1)

the current code starting line 80 is

template<typename Source, typename Sink>
std::streamsize copy_impl( Source& src, Sink& snk,
                            std::streamsize buffer_size,
                            mpl::false_, mpl::true_ )
{   // Copy from an indirect Source to a direct Sink.
     using namespace std;
     typedef typename char_type_of<Source>::type  char_type;
     typedef pair<char_type*, char_type*>         pair_type;
     detail::basic_buffer<char_type>  buf(buffer_size);
     pair_type                        p = snk.output_sequence();
     streamsize                       total = 0;
     bool                             done  = false;
     while (!done) {
         streamsize amt;
         done = (amt = iostreams::read(src, buf.data(), buffer_size)) == -1;
         std::copy(buf.data(), buf.data() + amt, p.first + total);
         if (amt != -1)
             total += amt;
     }
     return total;
}

I think it should be somthing like

template<typename Source, typename Sink>
std::streamsize copy_impl( Source& src, Sink& snk,
                            std::streamsize buffer_size,
                            mpl::false_, mpl::true_ )
{   // Copy from an indirect Source to a direct Sink.
     using namespace std;
     typedef typename char_type_of<Source>::type  char_type;
     typedef pair<char_type*, char_type*>         pair_type;
     detail::basic_buffer<char_type>  buf(buffer_size);
     pair_type                        p = snk.output_sequence();
     streamsize                       total = 0;
     streamsize                       amt   = 0;
     //bool                             done  = false;
     while ((amt = iostreams::read(src, buf.data(),buffer_size))!= -1) {
         std::copy(buf.data(), buf.data() + amt, p.first + total);
         total += amt;
     }
     return total;
}

The current code happens to crash whereas the proposed version works 
properly... Did I miss something or a I right ?

Regards,

Mathieu
--
http://matioupi.free.fr/