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

   1 // basic_ios member functions -*- C++ -*-
   2
   3 // Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
   4 // 2009  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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
  18 // permissions described in the GCC Runtime Library Exception, version
  19 // 3.1, as published by the Free Software Foundation.
  20
  21 // You should have received a copy of the GNU General Public License and
  22 // a copy of the GCC Runtime Library Exception along with this program;
  23 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 // <http://www.gnu.org/licenses/>.
  25
  26 /** @file bits/basic_ios.tcc
  27  *  This is an internal header file, included by other library headers.
  28  *  Do not attempt to use it directly. @headername{ios}
  29  */
  30
  31 #ifndef _BASIC_IOS_TCC
  32 #define _BASIC_IOS_TCC 1
  33
  34 #pragma GCC system_header
  35
  36 _GLIBCXX_BEGIN_NAMESPACE(std)
  37
  38   template<typename _CharT, typename _Traits>
  39     void
  40     basic_ios<_CharT, _Traits>::clear(iostate __state)
  41     {
  42       if (this->rdbuf())
  43         _M_streambuf_state = __state;
  44       else
  45           _M_streambuf_state = __state | badbit;
  46       if (this->exceptions() & this->rdstate())
  47         __throw_ios_failure(__N("basic_ios::clear"));
  48     }
  49
  50   template<typename _CharT, typename _Traits>
  51     basic_streambuf<_CharT, _Traits>*
  52     basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<_CharT, _Traits>* __sb)
  53     {
  54       basic_streambuf<_CharT, _Traits>* __old = _M_streambuf;
  55       _M_streambuf = __sb;
  56       this->clear();
  57       return __old;
  58     }
  59
  60   template<typename _CharT, typename _Traits>
  61     basic_ios<_CharT, _Traits>&
  62     basic_ios<_CharT, _Traits>::copyfmt(const basic_ios& __rhs)
  63     {
  64       // _GLIBCXX_RESOLVE_LIB_DEFECTS
  65       // 292. effects of a.copyfmt (a)
  66       if (this != &__rhs)
  67         {
  68           // Per 27.1.1, do not call imbue, yet must trash all caches
  69           // associated with imbue()
  70
  71           // Alloc any new word array first, so if it fails we have "rollback".
  72           _Words* __words = (__rhs._M_word_size <= _S_local_word_size) ?
  73                              _M_local_word : new _Words[__rhs._M_word_size];
  74
  75           // Bump refs before doing callbacks, for safety.
  76           _Callback_list* __cb = __rhs._M_callbacks;
  77           if (__cb)
  78             __cb->_M_add_reference();
  79           _M_call_callbacks(erase_event);
  80           if (_M_word != _M_local_word)
  81             {
  82               delete [] _M_word;
  83               _M_word = 0;
  84             }
  85           _M_dispose_callbacks();
  86
  87           // NB: Don't want any added during above.
  88           _M_callbacks = __cb;
  89           for (int __i = 0; __i < __rhs._M_word_size; ++__i)
  90             __words[__i] = __rhs._M_word[__i];
  91           _M_word = __words;
  92           _M_word_size = __rhs._M_word_size;
  93
  94           this->flags(__rhs.flags());
  95           this->width(__rhs.width());
  96           this->precision(__rhs.precision());
  97           this->tie(__rhs.tie());
  98           this->fill(__rhs.fill());
  99           _M_ios_locale = __rhs.getloc();
 100           _M_cache_locale(_M_ios_locale);
 101
 102           _M_call_callbacks(copyfmt_event);
 103
 104           // The next is required to be the last assignment.
 105           this->exceptions(__rhs.exceptions());
 106         }
 107       return *this;
 108     }
 109
 110   // Locales:
 111   template<typename _CharT, typename _Traits>
 112     locale
 113     basic_ios<_CharT, _Traits>::imbue(const locale& __loc)
 114     {
 115       locale __old(this->getloc());
 116       ios_base::imbue(__loc);
 117       _M_cache_locale(__loc);
 118       if (this->rdbuf() != 0)
 119         this->rdbuf()->pubimbue(__loc);
 120       return __old;
 121     }
 122
 123   template<typename _CharT, typename _Traits>
 124     void
 125     basic_ios<_CharT, _Traits>::init(basic_streambuf<_CharT, _Traits>* __sb)
 126     {
 127       // NB: This may be called more than once on the same object.
 128       ios_base::_M_init();
 129
 130       // Cache locale data and specific facets used by iostreams.
 131       _M_cache_locale(_M_ios_locale);
 132
 133       // NB: The 27.4.4.1 Postconditions Table specifies requirements
 134       // after basic_ios::init() has been called. As part of this,
 135       // fill() must return widen(' ') any time after init() has been
 136       // called, which needs an imbued ctype facet of char_type to
 137       // return without throwing an exception. Unfortunately,
 138       // ctype<char_type> is not necessarily a required facet, so
 139       // streams with char_type != [char, wchar_t] will not have it by
 140       // default. Because of this, the correct value for _M_fill is
 141       // constructed on the first call of fill(). That way,
 142       // unformatted input and output with non-required basic_ios
 143       // instantiations is possible even without imbuing the expected
 144       // ctype<char_type> facet.
 145       _M_fill = _CharT();
 146       _M_fill_init = false;
 147
 148       _M_tie = 0;
 149       _M_exception = goodbit;
 150       _M_streambuf = __sb;
 151       _M_streambuf_state = __sb ? goodbit : badbit;
 152     }
 153
 154   template<typename _CharT, typename _Traits>
 155     void
 156     basic_ios<_CharT, _Traits>::_M_cache_locale(const locale& __loc)
 157     {
 158       if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
 159         _M_ctype = &use_facet<__ctype_type>(__loc);
 160       else
 161         _M_ctype = 0;
 162
 163       if (__builtin_expect(has_facet<__num_put_type>(__loc), true))
 164         _M_num_put = &use_facet<__num_put_type>(__loc);
 165       else
 166         _M_num_put = 0;
 167
 168       if (__builtin_expect(has_facet<__num_get_type>(__loc), true))
 169         _M_num_get = &use_facet<__num_get_type>(__loc);
 170       else
 171         _M_num_get = 0;
 172     }
 173
 174   // Inhibit implicit instantiations for required instantiations,
 175   // which are defined via explicit instantiations elsewhere.
 176   // NB:  This syntax is a GNU extension.
 177 #if _GLIBCXX_EXTERN_TEMPLATE
 178   extern template class basic_ios<char>;
 179
 180 #ifdef _GLIBCXX_USE_WCHAR_T
 181   extern template class basic_ios<wchar_t>;
 182 #endif
 183 #endif
 184
 185 _GLIBCXX_END_NAMESPACE
 186
 187 #endif