Home | History | Annotate | Line # | Download | only in std 
      1 // <iosfwd> Forward declarations -*- C++ -*-
      2 
      3 // Copyright (C) 1997-2022 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
     17 // permissions described in the GCC Runtime Library Exception, version
     18 // 3.1, as published by the Free Software Foundation.
     19 
     20 // You should have received a copy of the GNU General Public License and
     21 // a copy of the GCC Runtime Library Exception along with this program;
     22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
     23 // <http://www.gnu.org/licenses/>.
     24 
     25 /** @file include/iosfwd
     26  *  This is a Standard C++ Library header.
     27  */
     28 
     29 //
     30 // ISO C++ 14882: 27.2  Forward declarations
     31 //
     32 
     33 #ifndef _GLIBCXX_IOSFWD
     34 #define _GLIBCXX_IOSFWD 1
     35 
     36 #pragma GCC system_header
     37 
     38 #include <bits/c++config.h>
     39 #include <bits/stringfwd.h> 	// For string forward declarations.
     40 #include <bits/postypes.h>
     41 
     42 namespace std _GLIBCXX_VISIBILITY(default)
     43 {
     44 _GLIBCXX_BEGIN_NAMESPACE_VERSION
     45 
     46   /**
     47    *  @defgroup io I/O
     48    *
     49    *  Nearly all of the I/O classes are parameterized on the type of
     50    *  characters they read and write.  (The major exception is ios_base at
     51    *  the top of the hierarchy.)  This is a change from pre-Standard
     52    *  streams, which were not templates.
     53    *
     54    *  For ease of use and compatibility, all of the basic_* I/O-related
     55    *  classes are given typedef names for both of the builtin character
     56    *  widths (wide and narrow).  The typedefs are the same as the
     57    *  pre-Standard names, for example:
     58    *
     59    *  @code
     60    *     typedef basic_ifstream<char>  ifstream;
     61    *  @endcode
     62    *
     63    *  Because properly forward-declaring these classes can be difficult, you
     64    *  should not do it yourself.  Instead, include the &lt;iosfwd&gt;
     65    *  header, which contains only declarations of all the I/O classes as
     66    *  well as the typedefs.  Trying to forward-declare the typedefs
     67    *  themselves (e.g., <code>class ostream;</code>) is not valid ISO C++.
     68    *
     69    *  For more specific declarations, see
     70    *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/io.html#std.io.objects
     71    *
     72    *  @{
     73   */
     74   class ios_base;
     75 
     76   template<typename _CharT, typename _Traits = char_traits<_CharT> >
     77     class basic_ios;
     78 
     79   template<typename _CharT, typename _Traits = char_traits<_CharT> >
     80     class basic_streambuf;
     81 
     82   template<typename _CharT, typename _Traits = char_traits<_CharT> >
     83     class basic_istream;
     84 
     85   template<typename _CharT, typename _Traits = char_traits<_CharT> >
     86     class basic_ostream;
     87 
     88   template<typename _CharT, typename _Traits = char_traits<_CharT> >
     89     class basic_iostream;
     90 
     91 
     92 _GLIBCXX_BEGIN_NAMESPACE_CXX11
     93 
     94   template<typename _CharT, typename _Traits = char_traits<_CharT>,
     95 	    typename _Alloc = allocator<_CharT> >
     96     class basic_stringbuf;
     97 
     98   template<typename _CharT, typename _Traits = char_traits<_CharT>,
     99 	   typename _Alloc = allocator<_CharT> >
    100     class basic_istringstream;
    101 
    102   template<typename _CharT, typename _Traits = char_traits<_CharT>,
    103 	   typename _Alloc = allocator<_CharT> >
    104     class basic_ostringstream;
    105 
    106   template<typename _CharT, typename _Traits = char_traits<_CharT>,
    107 	   typename _Alloc = allocator<_CharT> >
    108     class basic_stringstream;
    109 
    110 _GLIBCXX_END_NAMESPACE_CXX11
    111 
    112   template<typename _CharT, typename _Traits = char_traits<_CharT> >
    113     class basic_filebuf;
    114 
    115   template<typename _CharT, typename _Traits = char_traits<_CharT> >
    116     class basic_ifstream;
    117 
    118   template<typename _CharT, typename _Traits = char_traits<_CharT> >
    119     class basic_ofstream;
    120 
    121   template<typename _CharT, typename _Traits = char_traits<_CharT> >
    122     class basic_fstream;
    123 
    124   template<typename _CharT, typename _Traits = char_traits<_CharT> >
    125     class istreambuf_iterator;
    126 
    127   template<typename _CharT, typename _Traits = char_traits<_CharT> >
    128     class ostreambuf_iterator;
    129 
    130 
    131   /// Base class for @c char streams.
    132   typedef basic_ios<char> 		ios;
    133 
    134   /// Base class for @c char buffers.
    135   typedef basic_streambuf<char> 	streambuf;
    136 
    137   /// Base class for @c char input streams.
    138   typedef basic_istream<char> 		istream;
    139 
    140   /// Base class for @c char output streams.
    141   typedef basic_ostream<char> 		ostream;
    142 
    143   /// Base class for @c char mixed input and output streams.
    144   typedef basic_iostream<char> 		iostream;
    145 
    146   /// Class for @c char memory buffers.
    147   typedef basic_stringbuf<char> 	stringbuf;
    148 
    149   /// Class for @c char input memory streams.
    150   typedef basic_istringstream<char> 	istringstream;
    151 
    152   /// Class for @c char output memory streams.
    153   typedef basic_ostringstream<char> 	ostringstream;
    154 
    155   /// Class for @c char mixed input and output memory streams.
    156   typedef basic_stringstream<char> 	stringstream;
    157 
    158   /// Class for @c char file buffers.
    159   typedef basic_filebuf<char> 		filebuf;
    160 
    161   /// Class for @c char input file streams.
    162   typedef basic_ifstream<char> 		ifstream;
    163 
    164   /// Class for @c char output file streams.
    165   typedef basic_ofstream<char> 		ofstream;
    166 
    167   /// Class for @c char mixed input and output file streams.
    168   typedef basic_fstream<char> 		fstream;
    169 
    170 #ifdef _GLIBCXX_USE_WCHAR_T
    171   /// Base class for @c wchar_t streams.
    172   typedef basic_ios<wchar_t> 		wios;
    173 
    174   /// Base class for @c wchar_t buffers.
    175   typedef basic_streambuf<wchar_t> 	wstreambuf;
    176 
    177   /// Base class for @c wchar_t input streams.
    178   typedef basic_istream<wchar_t> 	wistream;
    179 
    180   /// Base class for @c wchar_t output streams.
    181   typedef basic_ostream<wchar_t> 	wostream;
    182 
    183   /// Base class for @c wchar_t mixed input and output streams.
    184   typedef basic_iostream<wchar_t> 	wiostream;
    185 
    186   /// Class for @c wchar_t memory buffers.
    187   typedef basic_stringbuf<wchar_t> 	wstringbuf;
    188 
    189   /// Class for @c wchar_t input memory streams.
    190   typedef basic_istringstream<wchar_t> 	wistringstream;
    191 
    192   /// Class for @c wchar_t output memory streams.
    193   typedef basic_ostringstream<wchar_t> 	wostringstream;
    194 
    195   /// Class for @c wchar_t mixed input and output memory streams.
    196   typedef basic_stringstream<wchar_t> 	wstringstream;
    197 
    198   /// Class for @c wchar_t file buffers.
    199   typedef basic_filebuf<wchar_t> 	wfilebuf;
    200 
    201   /// Class for @c wchar_t input file streams.
    202   typedef basic_ifstream<wchar_t> 	wifstream;
    203 
    204   /// Class for @c wchar_t output file streams.
    205   typedef basic_ofstream<wchar_t> 	wofstream;
    206 
    207   /// Class for @c wchar_t mixed input and output file streams.
    208   typedef basic_fstream<wchar_t> 	wfstream;
    209 #endif
    210 
    211 #if __cplusplus >= 202002L && _GLIBCXX_USE_CXX11_ABI
    212   template<typename _CharT, typename _Traits = char_traits<_CharT>,
    213            typename _Allocator = allocator<_CharT>>
    214     class basic_syncbuf;
    215   template<typename _CharT, typename _Traits = char_traits<_CharT>,
    216            typename _Allocator = allocator<_CharT>>
    217     class basic_osyncstream;
    218 
    219   using syncbuf = basic_syncbuf<char>;
    220   using osyncstream = basic_osyncstream<char>;
    221 
    222 #ifdef _GLIBCXX_USE_WCHAR_T
    223   using wsyncbuf = basic_syncbuf<wchar_t>;
    224   using wosyncstream = basic_osyncstream<wchar_t>;
    225 #endif
    226 #endif // C++20 && CXX11_ABI
    227 
    228 #if __cplusplus > 202002L
    229   template<typename _CharT, typename _Traits = char_traits<_CharT>>
    230     class basic_spanbuf;
    231   template<typename _CharT, typename _Traits = char_traits<_CharT>>
    232     class basic_ispanstream;
    233   template<typename _CharT, typename _Traits = char_traits<_CharT>>
    234     class basic_ospanstream;
    235   template<typename _CharT, typename _Traits = char_traits<_CharT>>
    236     class basic_spanstream;
    237 
    238   using spanbuf     = basic_spanbuf<char>;
    239   using ispanstream = basic_ispanstream<char>;
    240   using ospanstream = basic_ospanstream<char>;
    241   using spanstream  = basic_spanstream<char>;
    242 
    243 #ifdef _GLIBCXX_USE_WCHAR_T
    244   using wspanbuf     = basic_spanbuf<wchar_t>;
    245   using wispanstream = basic_ispanstream<wchar_t>;
    246   using wospanstream = basic_ospanstream<wchar_t>;
    247   using wspanstream  = basic_spanstream<wchar_t>;
    248 #endif
    249 #endif // C++23
    250 
    251   /** @}  */
    252 
    253 _GLIBCXX_END_NAMESPACE_VERSION
    254 } // namespace
    255 
    256 #endif /* _GLIBCXX_IOSFWD */
    257