ceph/src/boost/boost/tuple/tuple_io.hpp

   1 // tuple_io.hpp --------------------------------------------------------------
   2
   3 // Copyright (C) 2001 Jaakko Jarvi (jaakko.jarvi@cs.utu.fi)
   4 //               2001 Gary Powell (gary.powell@sierra.com)
   5 //
   6 // Distributed under the Boost Software License, Version 1.0. (See
   7 // accompanying file LICENSE_1_0.txt or copy at
   8 // http://www.boost.org/LICENSE_1_0.txt)
   9 // For more information, see http://www.boost.org
  10
  11 // ----------------------------------------------------------------------------
  12
  13 #ifndef BOOST_TUPLE_IO_HPP
  14 #define BOOST_TUPLE_IO_HPP
  15
  16 #include <istream>
  17 #include <ostream>
  18
  19 #include <sstream>
  20
  21 #include <boost/tuple/tuple.hpp>
  22
  23 // This is ugly: one should be using twoargument isspace since whitspace can
  24 // be locale dependent, in theory at least.
  25 // not all libraries implement have the two-arg version, so we need to
  26 // use the one-arg one, which one should get with <cctype> but there seem
  27 // to be exceptions to this.
  28
  29 #if !defined (BOOST_NO_STD_LOCALE)
  30
  31 #include <locale> // for two-arg isspace
  32
  33 #else
  34
  35 #include <cctype> // for one-arg (old) isspace
  36 #include <ctype.h> // Metrowerks does not find one-arg isspace from cctype
  37
  38 #endif
  39
  40 namespace boost {
  41 namespace tuples {
  42
  43 namespace detail {
  44
  45 class format_info {
  46 public:
  47
  48    enum manipulator_type { open, close, delimiter };
  49    BOOST_STATIC_CONSTANT(int, number_of_manipulators = delimiter + 1);
  50 private:
  51
  52    static int get_stream_index (int m)
  53    {
  54      static const int stream_index[number_of_manipulators]
  55         = { std::ios::xalloc(), std::ios::xalloc(), std::ios::xalloc() };
  56
  57      return stream_index[m];
  58    }
  59
  60    format_info(const format_info&);
  61    format_info();
  62
  63
  64 public:
  65
  66    template<class CharType, class CharTrait>
  67    static CharType get_manipulator(std::basic_ios<CharType, CharTrait>& i,
  68                                    manipulator_type m) {
  69      // The manipulators are stored as long.
  70      // A valid instanitation of basic_stream allows CharType to be any POD,
  71      // hence, the static_cast may fail (it fails if long is not convertible
  72      // to CharType
  73      CharType c = static_cast<CharType>(i.iword(get_stream_index(m)) );
  74      // parentheses and space are the default manipulators
  75      if (!c) {
  76        switch(m) {
  77          case detail::format_info::open :  c = i.widen('('); break;
  78          case detail::format_info::close : c = i.widen(')'); break;
  79          case detail::format_info::delimiter : c = i.widen(' '); break;
  80        }
  81      }
  82      return c;
  83    }
  84
  85
  86    template<class CharType, class CharTrait>
  87    static void set_manipulator(std::basic_ios<CharType, CharTrait>& i,
  88                                manipulator_type m, CharType c) {
  89      // The manipulators are stored as long.
  90      // A valid instanitation of basic_stream allows CharType to be any POD,
  91      // hence, the static_cast may fail (it fails if CharType is not
  92      // convertible long.
  93       i.iword(get_stream_index(m)) = static_cast<long>(c);
  94    }
  95 };
  96
  97 } // end of namespace detail
  98
  99 template<class CharType>
 100 class tuple_manipulator {
 101   const detail::format_info::manipulator_type mt;
 102   CharType f_c;
 103 public:
 104   explicit tuple_manipulator(detail::format_info::manipulator_type m,
 105                              const char c = 0)
 106      : mt(m), f_c(c) {}
 107
 108    template<class CharTrait>
 109   void set(std::basic_ios<CharType, CharTrait> &io) const {
 110      detail::format_info::set_manipulator(io, mt, f_c);
 111   }
 112 };
 113
 114
 115 template<class CharType, class CharTrait>
 116 inline std::basic_ostream<CharType, CharTrait>&
 117 operator<<(std::basic_ostream<CharType, CharTrait>& o, const tuple_manipulator<CharType>& m) {
 118   m.set(o);
 119   return o;
 120 }
 121
 122 template<class CharType, class CharTrait>
 123 inline std::basic_istream<CharType, CharTrait>&
 124 operator>>(std::basic_istream<CharType, CharTrait>& i, const tuple_manipulator<CharType>& m) {
 125   m.set(i);
 126   return i;
 127 }
 128
 129
 130 template<class CharType>
 131 inline tuple_manipulator<CharType> set_open(const CharType c) {
 132    return tuple_manipulator<CharType>(detail::format_info::open, c);
 133 }
 134
 135 template<class CharType>
 136 inline tuple_manipulator<CharType> set_close(const CharType c) {
 137    return tuple_manipulator<CharType>(detail::format_info::close, c);
 138 }
 139
 140 template<class CharType>
 141 inline tuple_manipulator<CharType> set_delimiter(const CharType c) {
 142    return tuple_manipulator<CharType>(detail::format_info::delimiter, c);
 143 }
 144
 145
 146
 147
 148
 149 // -------------------------------------------------------------
 150 // printing tuples to ostream in format (a b c)
 151 // parentheses and space are defaults, but can be overriden with manipulators
 152 // set_open, set_close and set_delimiter
 153
 154 namespace detail {
 155
 156 // Note: The order of the print functions is critical
 157 // to let a conforming compiler  find and select the correct one.
 158
 159
 160 template<class CharType, class CharTrait, class T1>
 161 inline std::basic_ostream<CharType, CharTrait>&
 162 print(std::basic_ostream<CharType, CharTrait>& o, const cons<T1, null_type>& t) {
 163   return o << t.head;
 164 }
 165
 166
 167 template<class CharType, class CharTrait>
 168 inline std::basic_ostream<CharType, CharTrait>&
 169 print(std::basic_ostream<CharType, CharTrait>& o, const null_type&) {
 170   return o;
 171 }
 172
 173 template<class CharType, class CharTrait, class T1, class T2>
 174 inline std::basic_ostream<CharType, CharTrait>&
 175 print(std::basic_ostream<CharType, CharTrait>& o, const cons<T1, T2>& t) {
 176
 177   const CharType d = format_info::get_manipulator(o, format_info::delimiter);
 178
 179   o << t.head;
 180
 181   o << d;
 182
 183   return print(o, t.tail);
 184 }
 185
 186 template<class CharT, class Traits, class T>
 187 inline bool handle_width(std::basic_ostream<CharT, Traits>& o, const T& t) {
 188     std::streamsize width = o.width();
 189     if(width == 0) return false;
 190
 191     std::basic_ostringstream<CharT, Traits> ss;
 192
 193     ss.copyfmt(o);
 194     ss.tie(0);
 195     ss.width(0);
 196
 197     ss << t;
 198     o << ss.str();
 199
 200     return true;
 201 }
 202
 203
 204 } // namespace detail
 205
 206
 207 template<class CharType, class CharTrait>
 208 inline std::basic_ostream<CharType, CharTrait>&
 209 operator<<(std::basic_ostream<CharType, CharTrait>& o,
 210            const null_type& t) {
 211   if (!o.good() ) return o;
 212   if (detail::handle_width(o, t)) return o;
 213
 214   const CharType l =
 215     detail::format_info::get_manipulator(o, detail::format_info::open);
 216   const CharType r =
 217     detail::format_info::get_manipulator(o, detail::format_info::close);
 218
 219   o << l;
 220   o << r;
 221
 222   return o;
 223 }
 224
 225 template<class CharType, class CharTrait, class T1, class T2>
 226 inline std::basic_ostream<CharType, CharTrait>&
 227 operator<<(std::basic_ostream<CharType, CharTrait>& o,
 228            const cons<T1, T2>& t) {
 229   if (!o.good() ) return o;
 230   if (detail::handle_width(o, t)) return o;
 231
 232   const CharType l =
 233     detail::format_info::get_manipulator(o, detail::format_info::open);
 234   const CharType r =
 235     detail::format_info::get_manipulator(o, detail::format_info::close);
 236
 237   o << l;
 238
 239   detail::print(o, t);
 240
 241   o << r;
 242
 243   return o;
 244 }
 245
 246
 247 // -------------------------------------------------------------
 248 // input stream operators
 249
 250 namespace detail {
 251
 252
 253 template<class CharType, class CharTrait>
 254 inline std::basic_istream<CharType, CharTrait>&
 255 extract_and_check_delimiter(
 256   std::basic_istream<CharType, CharTrait> &is, format_info::manipulator_type del)
 257 {
 258   const CharType d = format_info::get_manipulator(is, del);
 259
 260 #if defined (BOOST_NO_STD_LOCALE)
 261   const bool is_delimiter = !isspace(d);
 262 #elif defined ( __BORLANDC__ )
 263   const bool is_delimiter = !std::use_facet< std::ctype< CharType > >
 264     (is.getloc() ).is( std::ctype_base::space, d);
 265 #else
 266   const bool is_delimiter = (!std::isspace(d, is.getloc()) );
 267 #endif
 268
 269   CharType c;
 270   if (is_delimiter) {
 271     is >> c;
 272     if (is.good() && c!=d) {
 273       is.setstate(std::ios::failbit);
 274     }
 275   } else {
 276     is >> std::ws;
 277   }
 278   return is;
 279 }
 280
 281
 282 template<class CharType, class CharTrait, class T1>
 283 inline  std::basic_istream<CharType, CharTrait> &
 284 read (std::basic_istream<CharType, CharTrait> &is, cons<T1, null_type>& t1) {
 285
 286   if (!is.good()) return is;
 287
 288   return is >> t1.head;
 289 }
 290
 291 template<class CharType, class CharTrait, class T1, class T2>
 292 inline std::basic_istream<CharType, CharTrait>&
 293 read(std::basic_istream<CharType, CharTrait> &is, cons<T1, T2>& t1) {
 294
 295   if (!is.good()) return is;
 296
 297   is >> t1.head;
 298
 299
 300   extract_and_check_delimiter(is, format_info::delimiter);
 301
 302   return read(is, t1.tail);
 303 }
 304
 305 } // end namespace detail
 306
 307
 308 template<class CharType, class CharTrait>
 309 inline std::basic_istream<CharType, CharTrait>&
 310 operator>>(std::basic_istream<CharType, CharTrait> &is, null_type&) {
 311
 312   if (!is.good() ) return is;
 313
 314   detail::extract_and_check_delimiter(is, detail::format_info::open);
 315   detail::extract_and_check_delimiter(is, detail::format_info::close);
 316
 317   return is;
 318 }
 319
 320 template<class CharType, class CharTrait, class T1, class T2>
 321 inline std::basic_istream<CharType, CharTrait>&
 322 operator>>(std::basic_istream<CharType, CharTrait>& is, cons<T1, T2>& t1) {
 323
 324   if (!is.good() ) return is;
 325
 326   detail::extract_and_check_delimiter(is, detail::format_info::open);
 327
 328   detail::read(is, t1);
 329
 330   detail::extract_and_check_delimiter(is, detail::format_info::close);
 331
 332   return is;
 333 }
 334
 335
 336 } // end of namespace tuples
 337 } // end of namespace boost
 338
 339 #endif // BOOST_TUPLE_IO_HPP