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, 2010  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 namespace std _GLIBCXX_VISIBILITY(default)
  37 {
  38 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  39
  40   template<typename _CharT, typename _Traits>
  41     void
  42     basic_ios<_CharT, _Traits>::clear(iostate __state)
  43     {
  44       if (this->rdbuf())
  45         _M_streambuf_state = __state;
  46       else
  47           _M_streambuf_state = __state | badbit;
  48       if (this->exceptions() & this->rdstate())
  49         __throw_ios_failure(__N("basic_ios::clear"));
  50     }
  51
  52   template<typename _CharT, typename _Traits>
  53     basic_streambuf<_CharT, _Traits>*
  54     basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<_CharT, _Traits>* __sb)
  55     {
  56       basic_streambuf<_CharT, _Traits>* __old = _M_streambuf;
  57       _M_streambuf = __sb;
  58       this->clear();
  59       return __old;
  60     }
  61
  62   template<typename _CharT, typename _Traits>
  63     basic_ios<_CharT, _Traits>&
  64     basic_ios<_CharT, _Traits>::copyfmt(const basic_ios& __rhs)
  65     {
  66       // _GLIBCXX_RESOLVE_LIB_DEFECTS
  67       // 292. effects of a.copyfmt (a)
  68       if (this != &__rhs)
  69         {
  70           // Per 27.1.1, do not call imbue, yet must trash all caches
  71           // associated with imbue()
  72
  73           // Alloc any new word array first, so if it fails we have "rollback".
  74           _Words* __words = (__rhs._M_word_size <= _S_local_word_size) ?
  75                              _M_local_word : new _Words[__rhs._M_word_size];
  76
  77           // Bump refs before doing callbacks, for safety.
  78           _Callback_list* __cb = __rhs._M_callbacks;
  79           if (__cb)
  80             __cb->_M_add_reference();
  81           _M_call_callbacks(erase_event);
  82           if (_M_word != _M_local_word)
  83             {
  84               delete [] _M_word;
  85               _M_word = 0;
  86             }
  87           _M_dispose_callbacks();
  88
  89           // NB: Don't want any added during above.
  90           _M_callbacks = __cb;
  91           for (int __i = 0; __i < __rhs._M_word_size; ++__i)
  92             __words[__i] = __rhs._M_word[__i];
  93           _M_word = __words;
  94           _M_word_size = __rhs._M_word_size;
  95
  96           this->flags(__rhs.flags());
  97           this->width(__rhs.width());
  98           this->precision(__rhs.precision());
  99           this->tie(__rhs.tie());
 100           this->fill(__rhs.fill());
 101           _M_ios_locale = __rhs.getloc();
 102           _M_cache_locale(_M_ios_locale);
 103
 104           _M_call_callbacks(copyfmt_event);
 105
 106           // The next is required to be the last assignment.
 107           this->exceptions(__rhs.exceptions());
 108         }
 109       return *this;
 110     }
 111
 112   // Locales:
 113   template<typename _CharT, typename _Traits>
 114     locale
 115     basic_ios<_CharT, _Traits>::imbue(const locale& __loc)
 116     {
 117       locale __old(this->getloc());
 118       ios_base::imbue(__loc);
 119       _M_cache_locale(__loc);
 120       if (this->rdbuf() != 0)
 121         this->rdbuf()->pubimbue(__loc);
 122       return __old;
 123     }
 124
 125   template<typename _CharT, typename _Traits>
 126     void
 127     basic_ios<_CharT, _Traits>::init(basic_streambuf<_CharT, _Traits>* __sb)
 128     {
 129       // NB: This may be called more than once on the same object.
 130       ios_base::_M_init();
 131
 132       // Cache locale data and specific facets used by iostreams.
 133       _M_cache_locale(_M_ios_locale);
 134
 135       // NB: The 27.4.4.1 Postconditions Table specifies requirements
 136       // after basic_ios::init() has been called. As part of this,
 137       // fill() must return widen(' ') any time after init() has been
 138       // called, which needs an imbued ctype facet of char_type to
 139       // return without throwing an exception. Unfortunately,
 140       // ctype<char_type> is not necessarily a required facet, so
 141       // streams with char_type != [char, wchar_t] will not have it by
 142       // default. Because of this, the correct value for _M_fill is
 143       // constructed on the first call of fill(). That way,
 144       // unformatted input and output with non-required basic_ios
 145       // instantiations is possible even without imbuing the expected
 146       // ctype<char_type> facet.
 147       _M_fill = _CharT();
 148       _M_fill_init = false;
 149
 150       _M_tie = 0;
 151       _M_exception = goodbit;
 152       _M_streambuf = __sb;
 153       _M_streambuf_state = __sb ? goodbit : badbit;
 154     }
 155
 156   template<typename _CharT, typename _Traits>
 157     void
 158     basic_ios<_CharT, _Traits>::_M_cache_locale(const locale& __loc)
 159     {
 160       if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
 161         _M_ctype = &use_facet<__ctype_type>(__loc);
 162       else
 163         _M_ctype = 0;
 164
 165       if (__builtin_expect(has_facet<__num_put_type>(__loc), true))
 166         _M_num_put = &use_facet<__num_put_type>(__loc);
 167       else
 168         _M_num_put = 0;
 169
 170       if (__builtin_expect(has_facet<__num_get_type>(__loc), true))
 171         _M_num_get = &use_facet<__num_get_type>(__loc);
 172       else
 173         _M_num_get = 0;
 174     }
 175
 176   // Inhibit implicit instantiations for required instantiations,
 177   // which are defined via explicit instantiations elsewhere.
 178   // NB:  This syntax is a GNU extension.
 179 #if _GLIBCXX_EXTERN_TEMPLATE
 180   extern template class basic_ios<char>;
 181
 182 #ifdef _GLIBCXX_USE_WCHAR_T
 183   extern template class basic_ios<wchar_t>;
 184 #endif
 185 #endif
 186
 187 _GLIBCXX_END_NAMESPACE_VERSION
 188 } // namespace
 189
 190 #endif