libstdc++-v3/include/bits/quoted_string.h

   1 // Helpers for quoted stream manipulators -*- C++ -*-
   2
   3 // Copyright (C) 2013-2018 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 bits/quoted_string.h
  26  *  This is an internal header file, included by other library headers.
  27  *  Do not attempt to use it directly. @headername{iomanip}
  28  */
  29
  30 #ifndef _GLIBCXX_QUOTED_STRING_H
  31 #define _GLIBCXX_QUOTED_STRING_H 1
  32
  33 #pragma GCC system_header
  34
  35 #if __cplusplus < 201103L
  36 # include <bits/c++0x_warning.h>
  37 #else
  38 #include <sstream>
  39
  40 namespace std _GLIBCXX_VISIBILITY(default)
  41 {
  42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  43
  44   namespace __detail {
  45     /**
  46      * @brief Struct for delimited strings.
  47      */
  48     template<typename _String, typename _CharT>
  49       struct _Quoted_string
  50       {
  51         static_assert(is_reference<_String>::value
  52                    || is_pointer<_String>::value,
  53                       "String type must be pointer or reference");
  54
  55         _Quoted_string(_String __str, _CharT __del, _CharT __esc)
  56         : _M_string(__str), _M_delim{__del}, _M_escape{__esc}
  57         { }
  58
  59         _Quoted_string&
  60         operator=(_Quoted_string&) = delete;
  61
  62         _String _M_string;
  63         _CharT _M_delim;
  64         _CharT _M_escape;
  65       };
  66
  67 #if __cplusplus >= 201703L
  68     template<typename _CharT, typename _Traits>
  69       struct _Quoted_string<basic_string_view<_CharT, _Traits>, _CharT>
  70       {
  71         _Quoted_string(basic_string_view<_CharT, _Traits> __str,
  72                        _CharT __del, _CharT __esc)
  73         : _M_string(__str), _M_delim{__del}, _M_escape{__esc}
  74         { }
  75
  76         _Quoted_string&
  77         operator=(_Quoted_string&) = delete;
  78
  79         basic_string_view<_CharT, _Traits> _M_string;
  80         _CharT _M_delim;
  81         _CharT _M_escape;
  82       };
  83 #endif // C++17
  84
  85     /**
  86      * @brief Inserter for quoted strings.
  87      *
  88      *  _GLIBCXX_RESOLVE_LIB_DEFECTS
  89      *  DR 2344 quoted()'s interaction with padding is unclear
  90      */
  91     template<typename _CharT, typename _Traits>
  92       std::basic_ostream<_CharT, _Traits>&
  93       operator<<(std::basic_ostream<_CharT, _Traits>& __os,
  94                  const _Quoted_string<const _CharT*, _CharT>& __str)
  95       {
  96         std::basic_ostringstream<_CharT, _Traits> __ostr;
  97         __ostr << __str._M_delim;
  98         for (const _CharT* __c = __str._M_string; *__c; ++__c)
  99           {
 100             if (*__c == __str._M_delim || *__c == __str._M_escape)
 101               __ostr << __str._M_escape;
 102             __ostr << *__c;
 103           }
 104         __ostr << __str._M_delim;
 105
 106         return __os << __ostr.str();
 107       }
 108
 109     /**
 110      * @brief Inserter for quoted strings.
 111      *
 112      *  _GLIBCXX_RESOLVE_LIB_DEFECTS
 113      *  DR 2344 quoted()'s interaction with padding is unclear
 114      */
 115     template<typename _CharT, typename _Traits, typename _String>
 116       std::basic_ostream<_CharT, _Traits>&
 117       operator<<(std::basic_ostream<_CharT, _Traits>& __os,
 118                  const _Quoted_string<_String, _CharT>& __str)
 119       {
 120         std::basic_ostringstream<_CharT, _Traits> __ostr;
 121         __ostr << __str._M_delim;
 122         for (auto __c : __str._M_string)
 123           {
 124             if (__c == __str._M_delim || __c == __str._M_escape)
 125               __ostr << __str._M_escape;
 126             __ostr << __c;
 127           }
 128         __ostr << __str._M_delim;
 129
 130         return __os << __ostr.str();
 131       }
 132
 133     /**
 134      * @brief Extractor for delimited strings.
 135      *        The left and right delimiters can be different.
 136      */
 137     template<typename _CharT, typename _Traits, typename _Alloc>
 138       std::basic_istream<_CharT, _Traits>&
 139       operator>>(std::basic_istream<_CharT, _Traits>& __is,
 140                  const _Quoted_string<basic_string<_CharT, _Traits, _Alloc>&,
 141                                       _CharT>& __str)
 142       {
 143         _CharT __c;
 144         __is >> __c;
 145         if (!__is.good())
 146           return __is;
 147         if (__c != __str._M_delim)
 148           {
 149             __is.unget();
 150             __is >> __str._M_string;
 151             return __is;
 152           }
 153         __str._M_string.clear();
 154         std::ios_base::fmtflags __flags
 155           = __is.flags(__is.flags() & ~std::ios_base::skipws);
 156         do
 157           {
 158             __is >> __c;
 159             if (!__is.good())
 160               break;
 161             if (__c == __str._M_escape)
 162               {
 163                 __is >> __c;
 164                 if (!__is.good())
 165                   break;
 166               }
 167             else if (__c == __str._M_delim)
 168               break;
 169             __str._M_string += __c;
 170           }
 171         while (true);
 172         __is.setf(__flags);
 173
 174         return __is;
 175       }
 176   } // namespace __detail
 177
 178 _GLIBCXX_END_NAMESPACE_VERSION
 179 } // namespace std
 180
 181 #endif // C++11
 182 #endif /* _GLIBCXX_QUOTED_STRING_H */