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-rw-r--r--src/common/time_zone.cpp63
1 files changed, 59 insertions, 4 deletions
diff --git a/src/common/time_zone.cpp b/src/common/time_zone.cpp
index 126836b01..d8d7896c6 100644
--- a/src/common/time_zone.cpp
+++ b/src/common/time_zone.cpp
@@ -2,14 +2,33 @@
// SPDX-License-Identifier: GPL-2.0-or-later
#include <chrono>
+#include <exception>
#include <iomanip>
#include <sstream>
+#include <stdexcept>
+#include <fmt/chrono.h>
+#include <fmt/core.h>
#include "common/logging/log.h"
+#include "common/settings.h"
#include "common/time_zone.h"
namespace Common::TimeZone {
+// Time zone strings
+constexpr std::array timezones{
+ "GMT", "GMT", "CET", "CST6CDT", "Cuba", "EET", "Egypt", "Eire",
+ "EST", "EST5EDT", "GB", "GB-Eire", "GMT", "GMT+0", "GMT-0", "GMT0",
+ "Greenwich", "Hongkong", "HST", "Iceland", "Iran", "Israel", "Jamaica", "Japan",
+ "Kwajalein", "Libya", "MET", "MST", "MST7MDT", "Navajo", "NZ", "NZ-CHAT",
+ "Poland", "Portugal", "PRC", "PST8PDT", "ROC", "ROK", "Singapore", "Turkey",
+ "UCT", "Universal", "UTC", "W-SU", "WET", "Zulu",
+};
+
+const std::array<const char*, 46>& GetTimeZoneStrings() {
+ return timezones;
+}
+
std::string GetDefaultTimeZone() {
return "GMT";
}
@@ -18,10 +37,7 @@ static std::string GetOsTimeZoneOffset() {
const std::time_t t{std::time(nullptr)};
const std::tm tm{*std::localtime(&t)};
- std::stringstream ss;
- ss << std::put_time(&tm, "%z"); // Get the current timezone offset, e.g. "-400", as a string
-
- return ss.str();
+ return fmt::format("{:%z}", tm);
}
static int ConvertOsTimeZoneOffsetToInt(const std::string& timezone) {
@@ -45,4 +61,43 @@ std::chrono::seconds GetCurrentOffsetSeconds() {
return std::chrono::seconds{seconds};
}
+// Key is [Hours * 100 + Minutes], multiplied by 100 if DST
+const static std::map<s64, const char*> off_timezones = {
+ {530, "Asia/Calcutta"}, {930, "Australia/Darwin"}, {845, "Australia/Eucla"},
+ {103000, "Australia/Adelaide"}, {1030, "Australia/Lord_Howe"}, {630, "Indian/Cocos"},
+ {1245, "Pacific/Chatham"}, {134500, "Pacific/Chatham"}, {-330, "Canada/Newfoundland"},
+ {-23000, "Canada/Newfoundland"}, {430, "Asia/Kabul"}, {330, "Asia/Tehran"},
+ {43000, "Asia/Tehran"}, {545, "Asia/Kathmandu"}, {-930, "Asia/Marquesas"},
+};
+
+std::string FindSystemTimeZone() {
+#if defined(MINGW)
+ // MinGW has broken strftime -- https://sourceforge.net/p/mingw-w64/bugs/793/
+ // e.g. fmt::format("{:%z}") -- returns "Eastern Daylight Time" when it should be "-0400"
+ return timezones[0];
+#else
+ const s64 seconds = static_cast<s64>(GetCurrentOffsetSeconds().count());
+
+ const s64 minutes = seconds / 60;
+ const s64 hours = minutes / 60;
+
+ const s64 minutes_off = minutes - hours * 60;
+
+ if (minutes_off != 0) {
+ const auto the_time = std::time(nullptr);
+ const struct std::tm& local = *std::localtime(&the_time);
+ const bool is_dst = local.tm_isdst != 0;
+
+ const s64 tz_index = (hours * 100 + minutes_off) * (is_dst ? 100 : 1);
+
+ try {
+ return off_timezones.at(tz_index);
+ } catch (std::out_of_range&) {
+ LOG_ERROR(Common, "Time zone {} not handled, defaulting to hour offset.", tz_index);
+ }
+ }
+ return fmt::format("Etc/GMT{:s}{:d}", hours > 0 ? "-" : "+", std::abs(hours));
+#endif
+}
+
} // namespace Common::TimeZone