libstdc++-v3/include/bits/basic_ios.tcc

   1 // basic_ios member functions -*- C++ -*-
   2
   3 // Copyright (C) 1999, 2001, 2002, 2003, 2004, 2005
   4 // Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING.  If not, write to the Free
  19 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  20 // USA.
  21
  22 // As a special exception, you may use this file as part of a free software
  23 // library without restriction.  Specifically, if other files instantiate
  24 // templates or use macros or inline functions from this file, or you compile
  25 // this file and link it with other files to produce an executable, this
  26 // file does not by itself cause the resulting executable to be covered by
  27 // the GNU General Public License.  This exception does not however
  28 // invalidate any other reasons why the executable file might be covered by
  29 // the GNU General Public License.
  30
  31 /** @file basic_ios.tcc
  32  *  This is an internal header file, included by other library headers.
  33  *  You should not attempt to use it directly.
  34  */
  35
  36 #ifndef _BASIC_IOS_TCC
  37 #define _BASIC_IOS_TCC 1
  38
  39 #pragma GCC system_header
  40
  41 _GLIBCXX_BEGIN_NAMESPACE(std)
  42
  43   template<typename _CharT, typename _Traits>
  44     void
  45     basic_ios<_CharT, _Traits>::clear(iostate __state)
  46     {
  47       if (this->rdbuf())
  48         _M_streambuf_state = __state;
  49       else
  50           _M_streambuf_state = __state | badbit;
  51       if (this->exceptions() & this->rdstate())
  52         __throw_ios_failure(__N("basic_ios::clear"));
  53     }
  54
  55   template<typename _CharT, typename _Traits>
  56     basic_streambuf<_CharT, _Traits>*
  57     basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<_CharT, _Traits>* __sb)
  58     {
  59       basic_streambuf<_CharT, _Traits>* __old = _M_streambuf;
  60       _M_streambuf = __sb;
  61       this->clear();
  62       return __old;
  63     }
  64
  65   template<typename _CharT, typename _Traits>
  66     basic_ios<_CharT, _Traits>&
  67     basic_ios<_CharT, _Traits>::copyfmt(const basic_ios& __rhs)
  68     {
  69       // _GLIBCXX_RESOLVE_LIB_DEFECTS
  70       // 292. effects of a.copyfmt (a)
  71       if (this != &__rhs)
  72         {
  73           // Per 27.1.1, do not call imbue, yet must trash all caches
  74           // associated with imbue()
  75
  76           // Alloc any new word array first, so if it fails we have "rollback".
  77           _Words* __words = (__rhs._M_word_size <= _S_local_word_size) ?
  78                              _M_local_word : new _Words[__rhs._M_word_size];
  79
  80           // Bump refs before doing callbacks, for safety.
  81           _Callback_list* __cb = __rhs._M_callbacks;
  82           if (__cb)
  83             __cb->_M_add_reference();
  84           _M_call_callbacks(erase_event);
  85           if (_M_word != _M_local_word)
  86             {
  87               delete [] _M_word;
  88               _M_word = 0;
  89             }
  90           _M_dispose_callbacks();
  91
  92           // NB: Don't want any added during above.
  93           _M_callbacks = __cb;
  94           for (int __i = 0; __i < __rhs._M_word_size; ++__i)
  95             __words[__i] = __rhs._M_word[__i];
  96           _M_word = __words;
  97           _M_word_size = __rhs._M_word_size;
  98
  99           this->flags(__rhs.flags());
 100           this->width(__rhs.width());
 101           this->precision(__rhs.precision());
 102           this->tie(__rhs.tie());
 103           this->fill(__rhs.fill());
 104           _M_ios_locale = __rhs.getloc();
 105           _M_cache_locale(_M_ios_locale);
 106
 107           _M_call_callbacks(copyfmt_event);
 108
 109           // The next is required to be the last assignment.
 110           this->exceptions(__rhs.exceptions());
 111         }
 112       return *this;
 113     }
 114
 115   template<typename _CharT, typename _Traits>
 116     char
 117     basic_ios<_CharT, _Traits>::narrow(char_type __c, char __dfault) const
 118     { return __check_facet(_M_ctype).narrow(__c, __dfault); }
 119
 120   template<typename _CharT, typename _Traits>
 121     _CharT
 122     basic_ios<_CharT, _Traits>::widen(char __c) const
 123     { return __check_facet(_M_ctype).widen(__c); }
 124
 125   // Locales:
 126   template<typename _CharT, typename _Traits>
 127     locale
 128     basic_ios<_CharT, _Traits>::imbue(const locale& __loc)
 129     {
 130       locale __old(this->getloc());
 131       ios_base::imbue(__loc);
 132       _M_cache_locale(__loc);
 133       if (this->rdbuf() != 0)
 134         this->rdbuf()->pubimbue(__loc);
 135       return __old;
 136     }
 137
 138   template<typename _CharT, typename _Traits>
 139     void
 140     basic_ios<_CharT, _Traits>::init(basic_streambuf<_CharT, _Traits>* __sb)
 141     {
 142       // NB: This may be called more than once on the same object.
 143       ios_base::_M_init();
 144
 145       // Cache locale data and specific facets used by iostreams.
 146       _M_cache_locale(_M_ios_locale);
 147
 148       // NB: The 27.4.4.1 Postconditions Table specifies requirements
 149       // after basic_ios::init() has been called. As part of this,
 150       // fill() must return widen(' ') any time after init() has been
 151       // called, which needs an imbued ctype facet of char_type to
 152       // return without throwing an exception. Unfortunately,
 153       // ctype<char_type> is not necessarily a required facet, so
 154       // streams with char_type != [char, wchar_t] will not have it by
 155       // default. Because of this, the correct value for _M_fill is
 156       // constructed on the first call of fill(). That way,
 157       // unformatted input and output with non-required basic_ios
 158       // instantiations is possible even without imbuing the expected
 159       // ctype<char_type> facet.
 160       _M_fill = _CharT();
 161       _M_fill_init = false;
 162
 163       _M_tie = 0;
 164       _M_exception = goodbit;
 165       _M_streambuf = __sb;
 166       _M_streambuf_state = __sb ? goodbit : badbit;
 167     }
 168
 169   template<typename _CharT, typename _Traits>
 170     void
 171     basic_ios<_CharT, _Traits>::_M_cache_locale(const locale& __loc)
 172     {
 173       if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
 174         _M_ctype = &use_facet<__ctype_type>(__loc);
 175       else
 176         _M_ctype = 0;
 177
 178       if (__builtin_expect(has_facet<__num_put_type>(__loc), true))
 179         _M_num_put = &use_facet<__num_put_type>(__loc);
 180       else
 181         _M_num_put = 0;
 182
 183       if (__builtin_expect(has_facet<__num_get_type>(__loc), true))
 184         _M_num_get = &use_facet<__num_get_type>(__loc);
 185       else
 186         _M_num_get = 0;
 187     }
 188
 189   // Inhibit implicit instantiations for required instantiations,
 190   // which are defined via explicit instantiations elsewhere.
 191   // NB:  This syntax is a GNU extension.
 192 #if _GLIBCXX_EXTERN_TEMPLATE
 193   extern template class basic_ios<char>;
 194
 195 #ifdef _GLIBCXX_USE_WCHAR_T
 196   extern template class basic_ios<wchar_t>;
 197 #endif
 198 #endif
 199
 200 _GLIBCXX_END_NAMESPACE
 201
 202 #endif