libstdc++
quoted_string.h
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00001 // Helpers for quoted stream manipulators -*- C++ -*-
00002 
00003 // Copyright (C) 2013-2015 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /** @file bits/quoted_string.h
00026  *  This is an internal header file, included by other library headers.
00027  *  Do not attempt to use it directly. @headername{iomanip}
00028  */
00029 
00030 #ifndef _GLIBCXX_QUOTED_STRING_H
00031 #define _GLIBCXX_QUOTED_STRING_H 1
00032 
00033 #pragma GCC system_header
00034 
00035 #if __cplusplus < 201103L
00036 # include <bits/c++0x_warning.h>
00037 #else
00038 #include <sstream>
00039 
00040 namespace std _GLIBCXX_VISIBILITY(default)
00041 {
00042   namespace __detail {
00043   _GLIBCXX_BEGIN_NAMESPACE_VERSION
00044 
00045     /**
00046      * @brief Struct for delimited strings.
00047      */
00048     template<typename _String, typename _CharT>
00049       struct _Quoted_string
00050       {
00051         static_assert(is_reference<_String>::value
00052                    || is_pointer<_String>::value,
00053                       "String type must be pointer or reference");
00054 
00055         _Quoted_string(_String __str, _CharT __del, _CharT __esc)
00056         : _M_string(__str), _M_delim{__del}, _M_escape{__esc}
00057         { }
00058 
00059         _Quoted_string&
00060         operator=(_Quoted_string&) = delete;
00061 
00062         _String _M_string;
00063         _CharT _M_delim;
00064         _CharT _M_escape;
00065       };
00066 
00067     /**
00068      * @brief Inserter for quoted strings.
00069      *
00070      *  _GLIBCXX_RESOLVE_LIB_DEFECTS
00071      *  DR 2344 quoted()'s interaction with padding is unclear
00072      */
00073     template<typename _CharT, typename _Traits>
00074       std::basic_ostream<_CharT, _Traits>&
00075       operator<<(std::basic_ostream<_CharT, _Traits>& __os,
00076                  const _Quoted_string<const _CharT*, _CharT>& __str)
00077       {
00078         std::basic_ostringstream<_CharT, _Traits> __ostr;
00079         __ostr << __str._M_delim;
00080         for (const _CharT* __c = __str._M_string; *__c; ++__c)
00081           {
00082             if (*__c == __str._M_delim || *__c == __str._M_escape)
00083               __ostr << __str._M_escape;
00084             __ostr << *__c;
00085           }
00086         __ostr << __str._M_delim;
00087 
00088         return __os << __ostr.str();
00089       }
00090 
00091     /**
00092      * @brief Inserter for quoted strings.
00093      *
00094      *  _GLIBCXX_RESOLVE_LIB_DEFECTS
00095      *  DR 2344 quoted()'s interaction with padding is unclear
00096      */
00097     template<typename _CharT, typename _Traits, typename _String>
00098       std::basic_ostream<_CharT, _Traits>&
00099       operator<<(std::basic_ostream<_CharT, _Traits>& __os,
00100                  const _Quoted_string<_String, _CharT>& __str)
00101       {
00102         std::basic_ostringstream<_CharT, _Traits> __ostr;
00103         __ostr << __str._M_delim;
00104         for (auto& __c : __str._M_string)
00105           {
00106             if (__c == __str._M_delim || __c == __str._M_escape)
00107               __ostr << __str._M_escape;
00108             __ostr << __c;
00109           }
00110         __ostr << __str._M_delim;
00111 
00112         return __os << __ostr.str();
00113       }
00114 
00115     /**
00116      * @brief Extractor for delimited strings.
00117      *        The left and right delimiters can be different.
00118      */
00119     template<typename _CharT, typename _Traits, typename _Alloc>
00120       std::basic_istream<_CharT, _Traits>&
00121       operator>>(std::basic_istream<_CharT, _Traits>& __is,
00122                  const _Quoted_string<basic_string<_CharT, _Traits, _Alloc>&,
00123                                       _CharT>& __str)
00124       {
00125         _CharT __c;
00126         __is >> __c;
00127         if (!__is.good())
00128           return __is;
00129         if (__c != __str._M_delim)
00130           {
00131             __is.unget();
00132             __is >> __str._M_string;
00133             return __is;
00134           }
00135         __str._M_string.clear();
00136         std::ios_base::fmtflags __flags
00137           = __is.flags(__is.flags() & ~std::ios_base::skipws);
00138         do
00139           {
00140             __is >> __c;
00141             if (!__is.good())
00142               break;
00143             if (__c == __str._M_escape)
00144               {
00145                 __is >> __c;
00146                 if (!__is.good())
00147                   break;
00148               }
00149             else if (__c == __str._M_delim)
00150               break;
00151             __str._M_string += __c;
00152           }
00153         while (true);
00154         __is.setf(__flags);
00155 
00156         return __is;
00157       }
00158 
00159   _GLIBCXX_END_NAMESPACE_VERSION
00160   } // namespace __detail
00161 } // namespace std
00162 
00163 #endif // C++11
00164 #endif /* _GLIBCXX_QUOTED_STRING_H */