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 */
183