libstdc++
quoted_string.h
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1 // Helpers for quoted stream manipulators -*- C++ -*-
2 
3 // Copyright (C) 2013-2021 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>
50  {
51  static_assert(is_reference<_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 
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  {
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 
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>
94  const _Quoted_string<const _CharT*, _CharT>& __str)
95  {
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>
118  const _Quoted_string<_String, _CharT>& __str)
119  {
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>
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 */
ISO C++ entities toplevel namespace is std.
std::basic_ostream< _CharT, _Traits > & operator<<(std::basic_ostream< _CharT, _Traits > &__os, const _Quoted_string< const _CharT *, _CharT > &__str)
Inserter for quoted strings.
Definition: quoted_string.h:93
std::basic_istream< _CharT, _Traits > & operator>>(std::basic_istream< _CharT, _Traits > &__is, const _Quoted_string< basic_string< _CharT, _Traits, _Alloc > &, _CharT > &__str)
Extractor for delimited strings. The left and right delimiters can be different.
void clear(iostate __state=goodbit)
[Re]sets the error state.
Definition: basic_ios.tcc:41
bool good() const
Fast error checking.
Definition: basic_ios.h:180
Template class basic_istream.
Definition: istream:59
__istream_type & unget()
Unextracting the previous character.
Definition: istream.tcc:781
Template class basic_ostream.
Definition: ostream:59
Controlling output for std::string.
Definition: sstream:758
__string_type str() const
Copying out the string buffer.
Definition: sstream:916
A non-owning reference to a string.
Definition: string_view:100
is_reference
Definition: type_traits:560
is_pointer
Definition: type_traits:451
Managing sequences of characters and character-like objects.
fmtflags setf(fmtflags __fmtfl)
Setting new format flags.
Definition: ios_base.h:676
static const fmtflags skipws
Skips leading white space before certain input operations.
Definition: ios_base.h:386
fmtflags flags() const
Access to format flags.
Definition: ios_base.h:649
Struct for delimited strings.
Definition: quoted_string.h:50