Index: runtime/vm/os_win.cc |
diff --git a/runtime/vm/os_win.cc b/runtime/vm/os_win.cc |
index 96a00359df610e396aefefd1da4776a427c61a2d..b0f83214a71cd869f14bb3fcab0ce8cb2af22816 100644 |
--- a/runtime/vm/os_win.cc |
+++ b/runtime/vm/os_win.cc |
@@ -18,9 +18,11 @@ bool OS::GmTime(int64_t seconds_since_epoch, tm* tm_result) { |
} |
+// As a side-effect sets the globals _timezone, _daylight and _tzname. |
bool OS::LocalTime(int64_t seconds_since_epoch, tm* tm_result) { |
time_t seconds = static_cast<time_t>(seconds_since_epoch); |
if (seconds != seconds_since_epoch) return false; |
+ // localtime_s implicitly sets _timezone, _daylight and _tzname. |
errno_t error_code = localtime_s(tm_result, &seconds); |
return error_code == 0; |
} |
@@ -54,6 +56,53 @@ bool OS::MkTime(tm* tm, int64_t* seconds_result) { |
} |
+static int GetDaylightSavingBiasInSeconds() { |
+ TIME_ZONE_INFORMATION zone_information; |
+ memset(&zone_information, 0, sizeof(zone_information)); |
+ if (GetTimeZoneInformation(&zone_information) == TIME_ZONE_ID_INVALID) { |
+ // By default the daylight saving offset is an hour. |
+ return -60 * 60; |
+ } else { |
+ return static_cast<int>(zone_information.DaylightBias * 60); |
+ } |
+} |
+ |
+bool OS::GetTimeZoneName(int64_t seconds_since_epoch, |
+ const char** name_result) { |
+ tm decomposed; |
+ // LocalTime will set _tzname. |
+ bool succeeded = LocalTime(seconds_since_epoch, &decomposed); |
+ if (!succeeded) return false; |
+ int inDaylightSavingsTime = decomposed.tm_isdst; |
+ if (inDaylightSavingsTime != 0 && inDaylightSavingsTime != 1) { |
+ return false; |
+ } |
+ *name_result = _tzname[inDaylightSavingsTime]; |
+ return true; |
+} |
+ |
+ |
+bool OS::GetTimeZoneOffsetInSeconds(int64_t seconds_since_epoch, |
+ int* offset_result) { |
+ tm decomposed; |
+ // LocalTime will set _timezone. |
+ bool succeeded = LocalTime(seconds_since_epoch, &decomposed); |
+ if (!succeeded) return false; |
+ int inDaylightSavingsTime = decomposed.tm_isdst; |
+ if (inDaylightSavingsTime != 0 && inDaylightSavingsTime != 1) { |
+ return false; |
+ } |
+ // Dart and Windows disagree on the sign of the bias. |
+ *offset_result = static_cast<int>(-_timezone); |
+ if (inDaylightSavingsTime == 1) { |
+ static int daylight_bias = GetDaylightSavingBiasInSeconds() |
+ // Subtract because windows and Dart disagree on the sign. |
+ *offset_result -= daylight_bias; |
+ } |
+ return true; |
+} |
+ |
+ |
int64_t OS::GetCurrentTimeMillis() { |
return GetCurrentTimeMicros() / 1000; |
} |