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 _LIBCPP_HAS_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 && _LIBCPP_HAS_TIME_ZONE_DATABASE && _LIBCPP_HAS_FILESYSTEM && _LIBCPP_HAS_LOCALIZATION 35 36 namespace chrono { 37 38 class time_zone_link { 39 public: 40 [[nodiscard]] 41 _LIBCPP_HIDE_FROM_ABI explicit time_zone_link(__private_constructor_tag, string_view __name, string_view __target) 42 : __name_{__name}, __target_{__target} {} 43 44 _LIBCPP_HIDE_FROM_ABI time_zone_link(time_zone_link&&) = default; 45 _LIBCPP_HIDE_FROM_ABI time_zone_link& operator=(time_zone_link&&) = default; 46 47 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view name() const noexcept { return __name_; } 48 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI string_view target() const noexcept { return __target_; } 49 50 private: 51 string __name_; 52 // TODO TZDB instead of the name we can store the pointer to a zone. These 53 // pointers are immutable. This makes it possible to directly return a 54 // pointer in the time_zone in the 'locate_zone' function. 55 string __target_; 56 }; 57 58 [[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline bool 59 operator==(const time_zone_link& __x, const time_zone_link& __y) noexcept { 60 return __x.name() == __y.name(); 61 } 62 63 [[nodiscard]] _LIBCPP_AVAILABILITY_TZDB _LIBCPP_HIDE_FROM_ABI inline strong_ordering 64 operator<=>(const time_zone_link& __x, const time_zone_link& __y) noexcept { 65 return __x.name() <=> __y.name(); 66 } 67 68 } // namespace chrono 69 70 # endif // _LIBCPP_STD_VER >= 20 && _LIBCPP_HAS_TIME_ZONE_DATABASE && _LIBCPP_HAS_FILESYSTEM && 71 // _LIBCPP_HAS_LOCALIZATION 72 73 _LIBCPP_END_NAMESPACE_STD 74 75 _LIBCPP_POP_MACROS 76 77 #endif // _LIBCPP_HAS_EXPERIMENTAL_TZDB 78 79 #endif // _LIBCPP___CHRONO_TIME_ZONE_LINK_H 80