1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
|
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___FORMAT_WRITE_ESCAPED_H
#define _LIBCPP___FORMAT_WRITE_ESCAPED_H
#include <__algorithm/ranges_copy.h>
#include <__algorithm/ranges_for_each.h>
#include <__charconv/to_chars_integral.h>
#include <__charconv/to_chars_result.h>
#include <__chrono/statically_widen.h>
#include <__format/escaped_output_table.h>
#include <__format/formatter_output.h>
#include <__format/parser_std_format_spec.h>
#include <__format/unicode.h>
#include <__iterator/back_insert_iterator.h>
#include <__memory/addressof.h>
#include <__system_error/errc.h>
#include <__type_traits/make_unsigned.h>
#include <__utility/move.h>
#include <string_view>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
namespace __formatter {
#if _LIBCPP_STD_VER >= 20
/// Writes a string using format's width estimation algorithm.
///
/// \note When \c _LIBCPP_HAS_NO_UNICODE is defined the function assumes the
/// input is ASCII.
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI auto __write_string(
basic_string_view<_CharT> __str,
output_iterator<const _CharT&> auto __out_it,
__format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
if (!__specs.__has_precision())
return __formatter::__write_string_no_precision(__str, _VSTD::move(__out_it), __specs);
int __size = __formatter::__truncate(__str, __specs.__precision_);
return __formatter::__write(__str.begin(), __str.end(), _VSTD::move(__out_it), __specs, __size);
}
# endif // _LIBCPP_STD_VER >= 20
# if _LIBCPP_STD_VER >= 23
struct __nul_terminator {};
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI bool operator==(const _CharT* __cstr, __nul_terminator) {
return *__cstr == _CharT('\0');
}
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI void
__write_escaped_code_unit(basic_string<_CharT>& __str, char32_t __value, const _CharT* __prefix) {
back_insert_iterator __out_it{__str};
std::ranges::copy(__prefix, __nul_terminator{}, __out_it);
char __buffer[8];
to_chars_result __r = std::to_chars(std::begin(__buffer), std::end(__buffer), __value, 16);
_LIBCPP_ASSERT_UNCATEGORIZED(__r.ec == errc(0), "Internal buffer too small");
std::ranges::copy(std::begin(__buffer), __r.ptr, __out_it);
__str += _CharT('}');
}
// [format.string.escaped]/2.2.1.2
// ...
// then the sequence \u{hex-digit-sequence} is appended to E, where
// hex-digit-sequence is the shortest hexadecimal representation of C using
// lower-case hexadecimal digits.
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI void __write_well_formed_escaped_code_unit(basic_string<_CharT>& __str, char32_t __value) {
__formatter::__write_escaped_code_unit(__str, __value, _LIBCPP_STATICALLY_WIDEN(_CharT, "\\u{"));
}
// [format.string.escaped]/2.2.3
// Otherwise (X is a sequence of ill-formed code units), each code unit U is
// appended to E in order as the sequence \x{hex-digit-sequence}, where
// hex-digit-sequence is the shortest hexadecimal representation of U using
// lower-case hexadecimal digits.
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI void __write_escape_ill_formed_code_unit(basic_string<_CharT>& __str, char32_t __value) {
__formatter::__write_escaped_code_unit(__str, __value, _LIBCPP_STATICALLY_WIDEN(_CharT, "\\x{"));
}
template <class _CharT>
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool __is_escaped_sequence_written(basic_string<_CharT>& __str, char32_t __value) {
# ifdef _LIBCPP_HAS_NO_UNICODE
// For ASCII assume everything above 127 is printable.
if (__value > 127)
return false;
# endif
if (!__escaped_output_table::__needs_escape(__value))
return false;
__formatter::__write_well_formed_escaped_code_unit(__str, __value);
return true;
}
template <class _CharT>
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr char32_t __to_char32(_CharT __value) {
return static_cast<make_unsigned_t<_CharT>>(__value);
}
enum class __escape_quotation_mark { __apostrophe, __double_quote };
// [format.string.escaped]/2
template <class _CharT>
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI bool
__is_escaped_sequence_written(basic_string<_CharT>& __str, char32_t __value, __escape_quotation_mark __mark) {
// 2.2.1.1 - Mapped character in [tab:format.escape.sequences]
switch (__value) {
case _CharT('\t'):
__str += _LIBCPP_STATICALLY_WIDEN(_CharT, "\\t");
return true;
case _CharT('\n'):
__str += _LIBCPP_STATICALLY_WIDEN(_CharT, "\\n");
return true;
case _CharT('\r'):
__str += _LIBCPP_STATICALLY_WIDEN(_CharT, "\\r");
return true;
case _CharT('\''):
if (__mark == __escape_quotation_mark::__apostrophe)
__str += _LIBCPP_STATICALLY_WIDEN(_CharT, R"(\')");
else
__str += __value;
return true;
case _CharT('"'):
if (__mark == __escape_quotation_mark::__double_quote)
__str += _LIBCPP_STATICALLY_WIDEN(_CharT, R"(\")");
else
__str += __value;
return true;
case _CharT('\\'):
__str += _LIBCPP_STATICALLY_WIDEN(_CharT, R"(\\)");
return true;
// 2.2.1.2 - Space
case _CharT(' '):
__str += __value;
return true;
}
// 2.2.2
// Otherwise, if X is a shift sequence, the effect on E and further
// decoding of S is unspecified.
// For now shift sequences are ignored and treated as Unicode. Other parts
// of the format library do the same. It's unknown how ostream treats them.
// TODO FMT determine what to do with shift sequences.
// 2.2.1.2.1 and 2.2.1.2.2 - Escape
return __formatter::__is_escaped_sequence_written(__str, __formatter::__to_char32(__value));
}
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI void
__escape(basic_string<_CharT>& __str, basic_string_view<_CharT> __values, __escape_quotation_mark __mark) {
__unicode::__code_point_view<_CharT> __view{__values.begin(), __values.end()};
while (!__view.__at_end()) {
auto __first = __view.__position();
typename __unicode::__consume_result __result = __view.__consume();
if (__result.__status == __unicode::__consume_result::__ok) {
if (!__formatter::__is_escaped_sequence_written(__str, __result.__code_point, __mark))
// 2.2.1.3 - Add the character
ranges::copy(__first, __view.__position(), std::back_insert_iterator(__str));
} else {
// 2.2.3 sequence of ill-formed code units
ranges::for_each(__first, __view.__position(), [&](_CharT __value) {
__formatter::__write_escape_ill_formed_code_unit(__str, __formatter::__to_char32(__value));
});
}
}
}
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI auto
__format_escaped_char(_CharT __value,
output_iterator<const _CharT&> auto __out_it,
__format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
basic_string<_CharT> __str;
__str += _CharT('\'');
__formatter::__escape(__str, basic_string_view{std::addressof(__value), 1}, __escape_quotation_mark::__apostrophe);
__str += _CharT('\'');
return __formatter::__write(__str.data(), __str.data() + __str.size(), _VSTD::move(__out_it), __specs, __str.size());
}
template <class _CharT>
_LIBCPP_HIDE_FROM_ABI auto
__format_escaped_string(basic_string_view<_CharT> __values,
output_iterator<const _CharT&> auto __out_it,
__format_spec::__parsed_specifications<_CharT> __specs) -> decltype(__out_it) {
basic_string<_CharT> __str;
__str += _CharT('"');
__formatter::__escape(__str, __values, __escape_quotation_mark::__double_quote);
__str += _CharT('"');
return __formatter::__write_string(basic_string_view{__str}, _VSTD::move(__out_it), __specs);
}
# endif // _LIBCPP_STD_VER >= 23
} // namespace __formatter
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___FORMAT_WRITE_ESCAPED_H
|