1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// UNSUPPORTED: c++03, c++11, c++14, c++17
10// UNSUPPORTED: no-filesystem, no-localization, no-tzdb
11
12// XFAIL: libcpp-has-no-experimental-tzdb
13// XFAIL: availability-tzdb-missing
14
15// <chrono>
16
17// const time_zone* current_zone();
18
19#include <chrono>
20#include <cassert>
21#include <stdlib.h>
22#include <string_view>
23#include <string>
24
25#include "test_macros.h"
26#include "assert_macros.h"
27#include "concat_macros.h"
28
29#ifdef _WIN32
30static void set_tz(std::string zone) {
31 // Note Windows does not have setenv, only putenv
32 // https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/putenv-s-wputenv-s?view=msvc-170
33 // Unlike POSIX it does not mention the string of putenv becomes part
34 // of the environment.
35
36 int status = _putenv_s("TZ", zone.c_str());
37 assert(status == 0);
38}
39
40#else
41static void set_tz(const std::string& zone) {
42 int status = setenv(name: "TZ", value: zone.c_str(), replace: 1);
43 assert(status == 0);
44}
45#endif
46
47static void test_zone(const std::string& zone) {
48 set_tz(zone);
49 const std::chrono::time_zone* tz = std::chrono::current_zone();
50 assert(tz);
51 assert(tz->name() == zone);
52}
53
54static void test_link(const std::string& link, std::string_view zone) {
55 set_tz(link);
56 const std::chrono::time_zone* tz = std::chrono::current_zone();
57 assert(tz);
58 assert(tz->name() == zone);
59}
60
61int main(int, const char**) {
62 const std::chrono::time_zone* tz = std::chrono::current_zone();
63 // Returns a valid time zone, the value depends on the OS settings.
64 assert(tz);
65 // setting the environment to an invalid value returns the value of
66 // the OS setting.
67 set_tz("This is not a time zone");
68 assert(tz == std::chrono::current_zone());
69
70 const std::chrono::tzdb& db = std::chrono::get_tzdb();
71 for (const auto& zone : db.zones)
72 test_zone(std::string{zone.name()});
73
74 for (const auto& link : db.links)
75 test_link(std::string{link.name()}, link.target());
76
77 return 0;
78}
79

source code of libcxx/test/std/time/time.zone/time.zone.db/time.zone.db.access/current_zone.pass.cpp