1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9
10 #ifndef _LIBCPP___CHRONO_PARSER_STD_FORMAT_SPEC_H
11 #define _LIBCPP___CHRONO_PARSER_STD_FORMAT_SPEC_H
12
13 #include <__config>
14 #include <__format/concepts.h>
15 #include <__format/format_error.h>
16 #include <__format/format_parse_context.h>
17 #include <__format/formatter_string.h>
18 #include <__format/parser_std_format_spec.h>
19 #include <string_view>
20
21 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
22 # pragma GCC system_header
23 #endif
24
25 _LIBCPP_BEGIN_NAMESPACE_STD
26
27 #if _LIBCPP_STD_VER >= 20
28
29 namespace __format_spec {
30
31 // By not placing this constant in the formatter class it's not duplicated for char and wchar_t
32 inline constexpr __fields __fields_chrono_fractional{
33 .__precision_ = true, .__locale_specific_form_ = true, .__type_ = false};
34 inline constexpr __fields __fields_chrono{.__locale_specific_form_ = true, .__type_ = false};
35
36 /// Flags available or required in a chrono type.
37 ///
38 /// The caller of the chrono formatter lists the types it has available and the
39 /// validation tests whether the requested type spec (e.g. %M) is available in
40 /// the formatter.
41 /// When the type in the chrono-format-spec isn't present in the data a
42 /// \ref format_error is thrown.
43 enum class __flags {
44 __second = 0x1,
45 __minute = 0x2,
46 __hour = 0x4,
47 __time = __hour | __minute | __second,
48
49 __day = 0x8,
50 __month = 0x10,
51 __year = 0x20,
52
53 __weekday = 0x40,
54
55 __month_day = __day | __month,
56 __month_weekday = __weekday | __month,
57 __year_month = __month | __year,
58 __date = __day | __month | __year | __weekday,
59
60 __date_time = __date | __time,
61
62 __duration = 0x80 | __time,
63
64 __time_zone = 0x100,
65
66 __clock = __date_time | __time_zone
67 };
68
69 _LIBCPP_HIDE_FROM_ABI constexpr __flags operator&(__flags __lhs, __flags __rhs) {
70 return static_cast<__flags>(static_cast<unsigned>(__lhs) & static_cast<unsigned>(__rhs));
71 }
72
__validate_second(__flags __flags)73 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_second(__flags __flags) {
74 if ((__flags & __flags::__second) != __flags::__second)
75 std::__throw_format_error("The supplied date time doesn't contain a second");
76 }
77
__validate_minute(__flags __flags)78 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_minute(__flags __flags) {
79 if ((__flags & __flags::__minute) != __flags::__minute)
80 std::__throw_format_error("The supplied date time doesn't contain a minute");
81 }
82
__validate_hour(__flags __flags)83 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_hour(__flags __flags) {
84 if ((__flags & __flags::__hour) != __flags::__hour)
85 std::__throw_format_error("The supplied date time doesn't contain an hour");
86 }
87
__validate_time(__flags __flags)88 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_time(__flags __flags) {
89 if ((__flags & __flags::__time) != __flags::__time)
90 std::__throw_format_error("The supplied date time doesn't contain a time");
91 }
92
__validate_day(__flags __flags)93 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_day(__flags __flags) {
94 if ((__flags & __flags::__day) != __flags::__day)
95 std::__throw_format_error("The supplied date time doesn't contain a day");
96 }
97
__validate_month(__flags __flags)98 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_month(__flags __flags) {
99 if ((__flags & __flags::__month) != __flags::__month)
100 std::__throw_format_error("The supplied date time doesn't contain a month");
101 }
102
__validate_year(__flags __flags)103 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_year(__flags __flags) {
104 if ((__flags & __flags::__year) != __flags::__year)
105 std::__throw_format_error("The supplied date time doesn't contain a year");
106 }
107
__validate_date(__flags __flags)108 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_date(__flags __flags) {
109 if ((__flags & __flags::__date) != __flags::__date)
110 std::__throw_format_error("The supplied date time doesn't contain a date");
111 }
112
__validate_date_or_duration(__flags __flags)113 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_date_or_duration(__flags __flags) {
114 if (((__flags & __flags::__date) != __flags::__date) && ((__flags & __flags::__duration) != __flags::__duration))
115 std::__throw_format_error("The supplied date time doesn't contain a date or duration");
116 }
117
__validate_date_time(__flags __flags)118 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_date_time(__flags __flags) {
119 if ((__flags & __flags::__date_time) != __flags::__date_time)
120 std::__throw_format_error("The supplied date time doesn't contain a date and time");
121 }
122
__validate_weekday(__flags __flags)123 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_weekday(__flags __flags) {
124 if ((__flags & __flags::__weekday) != __flags::__weekday)
125 std::__throw_format_error("The supplied date time doesn't contain a weekday");
126 }
127
__validate_duration(__flags __flags)128 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_duration(__flags __flags) {
129 if ((__flags & __flags::__duration) != __flags::__duration)
130 std::__throw_format_error("The supplied date time doesn't contain a duration");
131 }
132
__validate_time_zone(__flags __flags)133 _LIBCPP_HIDE_FROM_ABI constexpr void __validate_time_zone(__flags __flags) {
134 if ((__flags & __flags::__time_zone) != __flags::__time_zone)
135 std::__throw_format_error("The supplied date time doesn't contain a time zone");
136 }
137
138 template <class _CharT>
139 class _LIBCPP_TEMPLATE_VIS __parser_chrono {
140 using _ConstIterator = typename basic_format_parse_context<_CharT>::const_iterator;
141
142 public:
143 template <class _ParseContext>
144 _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator
__parse(_ParseContext & __ctx,__fields __fields,__flags __flags)145 __parse(_ParseContext& __ctx, __fields __fields, __flags __flags) {
146 _ConstIterator __begin = __parser_.__parse(__ctx, __fields);
147 _ConstIterator __end = __ctx.end();
148 if (__begin == __end)
149 return __begin;
150
151 _ConstIterator __last = __parse_chrono_specs(__begin, __end, __flags);
152 __chrono_specs_ = basic_string_view<_CharT>{__begin, __last};
153
154 return __last;
155 }
156
157 __parser<_CharT> __parser_;
158 basic_string_view<_CharT> __chrono_specs_;
159
160 private:
161 _LIBCPP_HIDE_FROM_ABI constexpr _ConstIterator
__parse_chrono_specs(_ConstIterator __begin,_ConstIterator __end,__flags __flags)162 __parse_chrono_specs(_ConstIterator __begin, _ConstIterator __end, __flags __flags) {
163 _LIBCPP_ASSERT_INTERNAL(__begin != __end,
164 "When called with an empty input the function will cause "
165 "undefined behavior by evaluating data not in the input");
166
167 if (*__begin != _CharT('%') && *__begin != _CharT('}'))
168 std::__throw_format_error("The format specifier expects a '%' or a '}'");
169
170 do {
171 switch (*__begin) {
172 case _CharT('{'):
173 std::__throw_format_error("The chrono specifiers contain a '{'");
174
175 case _CharT('}'):
176 return __begin;
177
178 case _CharT('%'):
179 __parse_conversion_spec(__begin, __end, __flags);
180 [[fallthrough]];
181
182 default:
183 // All other literals
184 ++__begin;
185 }
186
187 } while (__begin != __end && *__begin != _CharT('}'));
188
189 return __begin;
190 }
191
192 /// \pre *__begin == '%'
193 /// \post __begin points at the end parsed conversion-spec
194 _LIBCPP_HIDE_FROM_ABI constexpr void
__parse_conversion_spec(_ConstIterator & __begin,_ConstIterator __end,__flags __flags)195 __parse_conversion_spec(_ConstIterator& __begin, _ConstIterator __end, __flags __flags) {
196 ++__begin;
197 if (__begin == __end)
198 std::__throw_format_error("End of input while parsing a conversion specifier");
199
200 switch (*__begin) {
201 case _CharT('n'):
202 case _CharT('t'):
203 case _CharT('%'):
204 break;
205
206 case _CharT('S'):
207 __format_spec::__validate_second(__flags);
208 break;
209
210 case _CharT('M'):
211 __format_spec::__validate_minute(__flags);
212 break;
213
214 case _CharT('p'): // TODO FMT does the formater require an hour or a time?
215 case _CharT('H'):
216 case _CharT('I'):
217 __parser_.__hour_ = true;
218 __validate_hour(__flags);
219 break;
220
221 case _CharT('r'):
222 case _CharT('R'):
223 case _CharT('T'):
224 case _CharT('X'):
225 __parser_.__hour_ = true;
226 __format_spec::__validate_time(__flags);
227 break;
228
229 case _CharT('d'):
230 case _CharT('e'):
231 __format_spec::__validate_day(__flags);
232 break;
233
234 case _CharT('b'):
235 case _CharT('h'):
236 case _CharT('B'):
237 __parser_.__month_name_ = true;
238 [[fallthrough]];
239 case _CharT('m'):
240 __format_spec::__validate_month(__flags);
241 break;
242
243 case _CharT('y'):
244 case _CharT('C'):
245 case _CharT('Y'):
246 __format_spec::__validate_year(__flags);
247 break;
248
249 case _CharT('j'):
250 __parser_.__day_of_year_ = true;
251 __format_spec::__validate_date_or_duration(__flags);
252 break;
253
254 case _CharT('g'):
255 case _CharT('G'):
256 case _CharT('U'):
257 case _CharT('V'):
258 case _CharT('W'):
259 __parser_.__week_of_year_ = true;
260 [[fallthrough]];
261 case _CharT('x'):
262 case _CharT('D'):
263 case _CharT('F'):
264 __format_spec::__validate_date(__flags);
265 break;
266
267 case _CharT('c'):
268 __format_spec::__validate_date_time(__flags);
269 break;
270
271 case _CharT('a'):
272 case _CharT('A'):
273 __parser_.__weekday_name_ = true;
274 [[fallthrough]];
275 case _CharT('u'):
276 case _CharT('w'):
277 __parser_.__weekday_ = true;
278 __validate_weekday(__flags);
279 __format_spec::__validate_weekday(__flags);
280 break;
281
282 case _CharT('q'):
283 case _CharT('Q'):
284 __format_spec::__validate_duration(__flags);
285 break;
286
287 case _CharT('E'):
288 __parse_modifier_E(__begin, __end, __flags);
289 break;
290
291 case _CharT('O'):
292 __parse_modifier_O(__begin, __end, __flags);
293 break;
294
295 case _CharT('z'):
296 case _CharT('Z'):
297 // Currently there's no time zone information. However some clocks have a
298 // hard-coded "time zone", for these clocks the information can be used.
299 // TODO FMT implement time zones.
300 __format_spec::__validate_time_zone(__flags);
301 break;
302
303 default: // unknown type;
304 std::__throw_format_error("The date time type specifier is invalid");
305 }
306 }
307
308 /// \pre *__begin == 'E'
309 /// \post __begin is incremented by one.
310 _LIBCPP_HIDE_FROM_ABI constexpr void
__parse_modifier_E(_ConstIterator & __begin,_ConstIterator __end,__flags __flags)311 __parse_modifier_E(_ConstIterator& __begin, _ConstIterator __end, __flags __flags) {
312 ++__begin;
313 if (__begin == __end)
314 std::__throw_format_error("End of input while parsing the modifier E");
315
316 switch (*__begin) {
317 case _CharT('X'):
318 __parser_.__hour_ = true;
319 __format_spec::__validate_time(__flags);
320 break;
321
322 case _CharT('y'):
323 case _CharT('C'):
324 case _CharT('Y'):
325 __format_spec::__validate_year(__flags);
326 break;
327
328 case _CharT('x'):
329 __format_spec::__validate_date(__flags);
330 break;
331
332 case _CharT('c'):
333 __format_spec::__validate_date_time(__flags);
334 break;
335
336 case _CharT('z'):
337 // Currently there's no time zone information. However some clocks have a
338 // hard-coded "time zone", for these clocks the information can be used.
339 // TODO FMT implement time zones.
340 __format_spec::__validate_time_zone(__flags);
341 break;
342
343 default:
344 std::__throw_format_error("The date time type specifier for modifier E is invalid");
345 }
346 }
347
348 /// \pre *__begin == 'O'
349 /// \post __begin is incremented by one.
350 _LIBCPP_HIDE_FROM_ABI constexpr void
__parse_modifier_O(_ConstIterator & __begin,_ConstIterator __end,__flags __flags)351 __parse_modifier_O(_ConstIterator& __begin, _ConstIterator __end, __flags __flags) {
352 ++__begin;
353 if (__begin == __end)
354 std::__throw_format_error("End of input while parsing the modifier O");
355
356 switch (*__begin) {
357 case _CharT('S'):
358 __format_spec::__validate_second(__flags);
359 break;
360
361 case _CharT('M'):
362 __format_spec::__validate_minute(__flags);
363 break;
364
365 case _CharT('I'):
366 case _CharT('H'):
367 __parser_.__hour_ = true;
368 __format_spec::__validate_hour(__flags);
369 break;
370
371 case _CharT('d'):
372 case _CharT('e'):
373 __format_spec::__validate_day(__flags);
374 break;
375
376 case _CharT('m'):
377 __format_spec::__validate_month(__flags);
378 break;
379
380 case _CharT('y'):
381 __format_spec::__validate_year(__flags);
382 break;
383
384 case _CharT('U'):
385 case _CharT('V'):
386 case _CharT('W'):
387 __parser_.__week_of_year_ = true;
388 __format_spec::__validate_date(__flags);
389 break;
390
391 case _CharT('u'):
392 case _CharT('w'):
393 __parser_.__weekday_ = true;
394 __format_spec::__validate_weekday(__flags);
395 break;
396
397 case _CharT('z'):
398 // Currently there's no time zone information. However some clocks have a
399 // hard-coded "time zone", for these clocks the information can be used.
400 // TODO FMT implement time zones.
401 __format_spec::__validate_time_zone(__flags);
402 break;
403
404 default:
405 std::__throw_format_error("The date time type specifier for modifier O is invalid");
406 }
407 }
408 };
409
410 } // namespace __format_spec
411
412 #endif //_LIBCPP_STD_VER >= 20
413
414 _LIBCPP_END_NAMESPACE_STD
415
416 #endif // _LIBCPP___CHRONO_PARSER_STD_FORMAT_SPEC_H
417