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// For information see https://libcxx.llvm.org/DesignDocs/TimeZone.html
11
12#ifndef _LIBCPP___CHRONO_TIME_ZONE_LINK_H
13#define _LIBCPP___CHRONO_TIME_ZONE_LINK_H
14
15#include <version>
16// Enable the contents of the header only when libc++ was built with experimental features enabled.
17#if !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
18
19# include <__compare/strong_order.h>
20# include <__config>
21# include <__utility/private_constructor_tag.h>
22# include <string>
23# include <string_view>
24
25# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
26# pragma GCC system_header
27# endif
28
29_LIBCPP_PUSH_MACROS
30# include <__undef_macros>
31
32_LIBCPP_BEGIN_NAMESPACE_STD
33
34# if _LIBCPP_STD_VER >= 20 && !defined(_LIBCPP_HAS_NO_TIME_ZONE_DATABASE) && !defined(_LIBCPP_HAS_NO_FILESYSTEM) && \
35 !defined(_LIBCPP_HAS_NO_LOCALIZATION)
36
37namespace chrono {
38
39class time_zone_link {
40public:
41 [[nodiscard]]
42 _LIBCPP_HIDE_FROM_ABI explicit time_zone_link(__private_constructor_tag, string_view __name, string_view __target)
43 : __name_{__name}, __target_{__target} {}
44
45 _LIBCPP_HIDE_FROM_ABI time_zone_link(time_zone_link&&) = default;
46 _LIBCPP_HIDE_FROM_ABI time_zone_link& operator=(time_zone_link&&) = default;
47
48 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view name() const noexcept { return __name_; }
49 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view target() const noexcept { return __target_; }
50
51private:
52 string __name_;
53 // TODO TZDB instead of the name we can store the pointer to a zone. These
54 // pointers are immutable. This makes it possible to directly return a
55 // pointer in the time_zone in the 'locate_zone' function.
56 string __target_;
57};
58
59[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline bool
60operator==(const time_zone_link& __x, const time_zone_link& __y) noexcept {
61 return __x.name() == __y.name();
62}
63
64[[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline strong_ordering
65operator<=>(const time_zone_link& __x, const time_zone_link& __y) noexcept {
66 return __x.name() <=> __y.name();
67}
68
69} // namespace chrono
70
71# endif //_LIBCPP_STD_VER >= 20
72
73_LIBCPP_END_NAMESPACE_STD
74
75_LIBCPP_POP_MACROS
76
77#endif // !defined(_LIBCPP_HAS_NO_EXPERIMENTAL_TZDB)
78
79#endif // _LIBCPP___CHRONO_TIME_ZONE_LINK_H
80