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     /**
68      * @brief Inserter for quoted strings.
69      *
70      *  _GLIBCXX_RESOLVE_LIB_DEFECTS
71      *  DR 2344 quoted()'s interaction with padding is unclear
72      */
73     template<typename _CharT, typename _Traits>
74       std::basic_ostream<_CharT, _Traits>&
75       operator<<(std::basic_ostream<_CharT, _Traits>& __os,
76 		 const _Quoted_string<const _CharT*, _CharT>& __str)
77       {
78 	std::basic_ostringstream<_CharT, _Traits> __ostr;
79 	__ostr << __str._M_delim;
80 	for (const _CharT* __c = __str._M_string; *__c; ++__c)
81 	  {
82 	    if (*__c == __str._M_delim || *__c == __str._M_escape)
83 	      __ostr << __str._M_escape;
84 	    __ostr << *__c;
85 	  }
86 	__ostr << __str._M_delim;
87 
88 	return __os << __ostr.str();
89       }
90 
91     /**
92      * @brief Inserter for quoted strings.
93      *
94      *  _GLIBCXX_RESOLVE_LIB_DEFECTS
95      *  DR 2344 quoted()'s interaction with padding is unclear
96      */
97     template<typename _CharT, typename _Traits, typename _String>
98       std::basic_ostream<_CharT, _Traits>&
99       operator<<(std::basic_ostream<_CharT, _Traits>& __os,
100 		 const _Quoted_string<_String, _CharT>& __str)
101       {
102 	std::basic_ostringstream<_CharT, _Traits> __ostr;
103 	__ostr << __str._M_delim;
104 	for (auto& __c : __str._M_string)
105 	  {
106 	    if (__c == __str._M_delim || __c == __str._M_escape)
107 	      __ostr << __str._M_escape;
108 	    __ostr << __c;
109 	  }
110 	__ostr << __str._M_delim;
111 
112 	return __os << __ostr.str();
113       }
114 
115     /**
116      * @brief Extractor for delimited strings.
117      *        The left and right delimiters can be different.
118      */
119     template<typename _CharT, typename _Traits, typename _Alloc>
120       std::basic_istream<_CharT, _Traits>&
121       operator>>(std::basic_istream<_CharT, _Traits>& __is,
122 		 const _Quoted_string<basic_string<_CharT, _Traits, _Alloc>&,
123 				      _CharT>& __str)
124       {
125 	_CharT __c;
126 	__is >> __c;
127 	if (!__is.good())
128 	  return __is;
129 	if (__c != __str._M_delim)
130 	  {
131 	    __is.unget();
132 	    __is >> __str._M_string;
133 	    return __is;
134 	  }
135 	__str._M_string.clear();
136 	std::ios_base::fmtflags __flags
137 	  = __is.flags(__is.flags() & ~std::ios_base::skipws);
138 	do
139 	  {
140 	    __is >> __c;
141 	    if (!__is.good())
142 	      break;
143 	    if (__c == __str._M_escape)
144 	      {
145 		__is >> __c;
146 		if (!__is.good())
147 		  break;
148 	      }
149 	    else if (__c == __str._M_delim)
150 	      break;
151 	    __str._M_string += __c;
152 	  }
153 	while (true);
154 	__is.setf(__flags);
155 
156 	return __is;
157       }
158   } // namespace __detail
159 
160 _GLIBCXX_END_NAMESPACE_VERSION
161 } // namespace std
162 
163 #endif // C++11
164 #endif /* _GLIBCXX_QUOTED_STRING_H */
165