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

   1 // basic_ios member functions -*- C++ -*-
   2
   3 // Copyright (C) 1999, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 2, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING.  If not, write to the Free
  18 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  19 // USA.
  20
  21 // As a special exception, you may use this file as part of a free software
  22 // library without restriction.  Specifically, if other files instantiate
  23 // templates or use macros or inline functions from this file, or you compile
  24 // this file and link it with other files to produce an executable, this
  25 // file does not by itself cause the resulting executable to be covered by
  26 // the GNU General Public License.  This exception does not however
  27 // invalidate any other reasons why the executable file might be covered by
  28 // the GNU General Public License.
  29
  30 #ifndef _BASIC_IOS_TCC
  31 #define _BASIC_IOS_TCC 1
  32
  33 #pragma GCC system_header
  34
  35 namespace std
  36 {
  37   template<typename _CharT, typename _Traits>
  38     void
  39     basic_ios<_CharT, _Traits>::clear(iostate __state)
  40     {
  41       if (this->rdbuf())
  42         _M_streambuf_state = __state;
  43       else
  44           _M_streambuf_state = __state | badbit;
  45       if (this->exceptions() & this->rdstate())
  46         __throw_ios_failure(__N("basic_ios::clear"));
  47     }
  48
  49   template<typename _CharT, typename _Traits>
  50     basic_streambuf<_CharT, _Traits>*
  51     basic_ios<_CharT, _Traits>::rdbuf(basic_streambuf<_CharT, _Traits>* __sb)
  52     {
  53       basic_streambuf<_CharT, _Traits>* __old = _M_streambuf;
  54       _M_streambuf = __sb;
  55       this->clear();
  56       return __old;
  57     }
  58
  59   template<typename _CharT, typename _Traits>
  60     basic_ios<_CharT, _Traits>&
  61     basic_ios<_CharT, _Traits>::copyfmt(const basic_ios& __rhs)
  62     {
  63       // _GLIBCXX_RESOLVE_LIB_DEFECTS
  64       // 292. effects of a.copyfmt (a)
  65       if (this != &__rhs)
  66         {
  67           // Per 27.1.1, do not call imbue, yet must trash all caches
  68           // associated with imbue()
  69
  70           // Alloc any new word array first, so if it fails we have "rollback".
  71           _Words* __words = (__rhs._M_word_size <= _S_local_word_size) ?
  72                              _M_local_word : new _Words[__rhs._M_word_size];
  73
  74           // Bump refs before doing callbacks, for safety.
  75           _Callback_list* __cb = __rhs._M_callbacks;
  76           if (__cb)
  77             __cb->_M_add_reference();
  78           _M_call_callbacks(erase_event);
  79           if (_M_word != _M_local_word)
  80             {
  81               delete [] _M_word;
  82               _M_word = 0;
  83             }
  84           _M_dispose_callbacks();
  85
  86           // NB: Don't want any added during above.
  87           _M_callbacks = __cb;
  88           for (int __i = 0; __i < __rhs._M_word_size; ++__i)
  89             __words[__i] = __rhs._M_word[__i];
  90           _M_word = __words;
  91           _M_word_size = __rhs._M_word_size;
  92
  93           this->flags(__rhs.flags());
  94           this->width(__rhs.width());
  95           this->precision(__rhs.precision());
  96           this->tie(__rhs.tie());
  97           this->fill(__rhs.fill());
  98           _M_ios_locale = __rhs.getloc();
  99           _M_cache_locale(_M_ios_locale);
 100
 101           _M_call_callbacks(copyfmt_event);
 102
 103           // The next is required to be the last assignment.
 104           this->exceptions(__rhs.exceptions());
 105         }
 106       return *this;
 107     }
 108
 109   template<typename _CharT, typename _Traits>
 110     char
 111     basic_ios<_CharT, _Traits>::narrow(char_type __c, char __dfault) const
 112     { return __check_facet(_M_ctype).narrow(__c, __dfault); }
 113
 114   template<typename _CharT, typename _Traits>
 115     _CharT
 116     basic_ios<_CharT, _Traits>::widen(char __c) const
 117     { return __check_facet(_M_ctype).widen(__c); }
 118
 119   // Locales:
 120   template<typename _CharT, typename _Traits>
 121     locale
 122     basic_ios<_CharT, _Traits>::imbue(const locale& __loc)
 123     {
 124       locale __old(this->getloc());
 125       ios_base::imbue(__loc);
 126       _M_cache_locale(__loc);
 127       if (this->rdbuf() != 0)
 128         this->rdbuf()->pubimbue(__loc);
 129       return __old;
 130     }
 131
 132   template<typename _CharT, typename _Traits>
 133     void
 134     basic_ios<_CharT, _Traits>::init(basic_streambuf<_CharT, _Traits>* __sb)
 135     {
 136       // NB: This may be called more than once on the same object.
 137       ios_base::_M_init();
 138
 139       // Cache locale data and specific facets used by iostreams.
 140       _M_cache_locale(_M_ios_locale);
 141
 142       // NB: The 27.4.4.1 Postconditions Table specifies requirements
 143       // after basic_ios::init() has been called. As part of this,
 144       // fill() must return widen(' ') any time after init() has been
 145       // called, which needs an imbued ctype facet of char_type to
 146       // return without throwing an exception. Unfortunately,
 147       // ctype<char_type> is not necessarily a required facet, so
 148       // streams with char_type != [char, wchar_t] will not have it by
 149       // default. Because of this, the correct value for _M_fill is
 150       // constructed on the first call of fill(). That way,
 151       // unformatted input and output with non-required basic_ios
 152       // instantiations is possible even without imbuing the expected
 153       // ctype<char_type> facet.
 154       _M_fill = _CharT();
 155       _M_fill_init = false;
 156
 157       _M_tie = 0;
 158       _M_exception = goodbit;
 159       _M_streambuf = __sb;
 160       _M_streambuf_state = __sb ? goodbit : badbit;
 161     }
 162
 163   template<typename _CharT, typename _Traits>
 164     void
 165     basic_ios<_CharT, _Traits>::_M_cache_locale(const locale& __loc)
 166     {
 167       if (__builtin_expect(has_facet<__ctype_type>(__loc), true))
 168         _M_ctype = &use_facet<__ctype_type>(__loc);
 169       else
 170         _M_ctype = 0;
 171
 172       if (__builtin_expect(has_facet<__num_put_type>(__loc), true))
 173         _M_num_put = &use_facet<__num_put_type>(__loc);
 174       else
 175         _M_num_put = 0;
 176
 177       if (__builtin_expect(has_facet<__num_get_type>(__loc), true))
 178         _M_num_get = &use_facet<__num_get_type>(__loc);
 179       else
 180         _M_num_get = 0;
 181     }
 182
 183   // Inhibit implicit instantiations for required instantiations,
 184   // which are defined via explicit instantiations elsewhere.
 185   // NB:  This syntax is a GNU extension.
 186 #if _GLIBCXX_EXTERN_TEMPLATE
 187   extern template class basic_ios<char>;
 188
 189 #ifdef _GLIBCXX_USE_WCHAR_T
 190   extern template class basic_ios<wchar_t>;
 191 #endif
 192 #endif
 193 } // namespace std
 194
 195 #endif