boost/boost/iostreams/write.hpp

   1 // (C) Copyright Jonathan Turkanis 2003.
   2 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   3 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
   4
   5 // See http://www.boost.org/libs/iostreams for documentation.
   6
   7 #ifndef BOOST_IOSTREAMS_WRITE_HPP_INCLUDED
   8 #define BOOST_IOSTREAMS_WRITE_HPP_INCLUDED
   9
  10 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
  11 # pragma once
  12 #endif
  13
  14 #include <boost/config.hpp>  // DEDUCED_TYPENAME, MSVC.
  15 #include <boost/detail/workaround.hpp>
  16 #include <boost/iostreams/categories.hpp>
  17 #include <boost/iostreams/detail/char_traits.hpp>
  18 #include <boost/iostreams/detail/dispatch.hpp>
  19 #include <boost/iostreams/detail/ios.hpp>  // streamsize.
  20 #include <boost/iostreams/detail/streambuf.hpp>
  21 #include <boost/iostreams/detail/wrap_unwrap.hpp>
  22 #include <boost/iostreams/operations_fwd.hpp>
  23 #include <boost/iostreams/traits.hpp>
  24 #include <boost/mpl/if.hpp>
  25
  26 // Must come last.
  27 #include <boost/iostreams/detail/config/disable_warnings.hpp>
  28
  29 #if BOOST_WORKAROUND(BOOST_MSVC, < 1300) //-----------------------------------//
  30 # include <boost/iostreams/detail/vc6/write.hpp>
  31 #else // #if BOOST_WORKAROUND(BOOST_MSVC, < 1300) //--------------------------//
  32
  33 namespace boost { namespace iostreams {
  34
  35 namespace detail {
  36
  37 template<typename T>
  38 struct write_device_impl;
  39
  40 template<typename T>
  41 struct write_filter_impl;
  42
  43 } // End namespace detail.
  44
  45 template<typename T>
  46 bool put(T& t, typename char_type_of<T>::type c)
  47 { return detail::write_device_impl<T>::put(detail::unwrap(t), c); }
  48
  49 template<typename T>
  50 inline std::streamsize write
  51     (T& t, const typename char_type_of<T>::type* s, std::streamsize n)
  52 { return detail::write_device_impl<T>::write(detail::unwrap(t), s, n); }
  53
  54 template<typename T, typename Sink>
  55 inline std::streamsize
  56 write( T& t, Sink& snk, const typename char_type_of<T>::type* s,
  57        std::streamsize n )
  58 { return detail::write_filter_impl<T>::write(detail::unwrap(t), snk, s, n); }
  59
  60 namespace detail {
  61
  62 //------------------Definition of write_device_impl---------------------------//
  63
  64 template<typename T>
  65 struct write_device_impl
  66     : mpl::if_<
  67           is_custom<T>,
  68           operations<T>,
  69           write_device_impl<
  70               BOOST_DEDUCED_TYPENAME
  71               dispatch<
  72                   T, ostream_tag, streambuf_tag, output
  73               >::type
  74           >
  75       >::type
  76     { };
  77
  78 template<>
  79 struct write_device_impl<ostream_tag> {
  80     template<typename T>
  81     static bool put(T& t, typename char_type_of<T>::type c)
  82     {
  83         typedef typename char_type_of<T>::type          char_type;
  84         typedef BOOST_IOSTREAMS_CHAR_TRAITS(char_type)  traits_type;
  85         return !traits_type::eq_int_type( t.rdbuf()->s.sputc(),
  86                                           traits_type::eof() );
  87     }
  88
  89     template<typename T>
  90     static std::streamsize write
  91         (T& t, const typename char_type_of<T>::type* s, std::streamsize n)
  92     { return t.rdbuf()->sputn(s, n); }
  93 };
  94
  95 template<>
  96 struct write_device_impl<streambuf_tag> {
  97     template<typename T>
  98     static bool put(T& t, typename char_type_of<T>::type c)
  99     {
 100         typedef typename char_type_of<T>::type          char_type;
 101         typedef BOOST_IOSTREAMS_CHAR_TRAITS(char_type)  traits_type;
 102         return !traits_type::eq_int_type(t.sputc(c), traits_type::eof());
 103     }
 104
 105     template<typename T>
 106     static std::streamsize write
 107         (T& t, const typename char_type_of<T>::type* s, std::streamsize n)
 108     { return t.sputn(s, n); }
 109 };
 110
 111 template<>
 112 struct write_device_impl<output> {
 113     template<typename T>
 114     static bool put(T& t, typename char_type_of<T>::type c)
 115     { return t.write(&c, 1) == 1; }
 116
 117     template<typename T>
 118     static std::streamsize
 119     write(T& t, const typename char_type_of<T>::type* s, std::streamsize n)
 120     { return t.write(s, n); }
 121 };
 122
 123 //------------------Definition of write_filter_impl---------------------------//
 124
 125 template<typename T>
 126 struct write_filter_impl
 127     : mpl::if_<
 128           is_custom<T>,
 129           operations<T>,
 130           write_filter_impl<
 131               BOOST_DEDUCED_TYPENAME
 132               dispatch<
 133                   T, multichar_tag, any_tag
 134               >::type
 135           >
 136       >::type
 137     { };
 138
 139 template<>
 140 struct write_filter_impl<multichar_tag> {
 141     template<typename T, typename Sink>
 142     static std::streamsize
 143     write( T& t, Sink& snk, const typename char_type_of<T>::type* s,
 144            std::streamsize n )
 145     { return t.write(snk, s, n); }
 146 };
 147
 148 template<>
 149 struct write_filter_impl<any_tag> {
 150     template<typename T, typename Sink>
 151     static std::streamsize
 152     write( T& t, Sink& snk, const typename char_type_of<T>::type* s,
 153            std::streamsize n )
 154     {
 155         for (std::streamsize off = 0; off < n; ++off)
 156             if (!t.put(snk, s[off]))
 157                 return off;
 158         return n;
 159     }
 160 };
 161
 162 } // End namespace detail.
 163
 164 } } // End namespaces iostreams, boost.
 165
 166 #endif // #if BOOST_WORKAROUND(BOOST_MSVC, < 1300) //-------------------------//
 167
 168 #include <boost/iostreams/detail/config/enable_warnings.hpp>
 169
 170 #endif // #ifndef BOOST_IOSTREAMS_WRITE_HPP_INCLUDED