From abfd341464b32d5cd914c5f3ffde6c8cd8dc10ca Mon Sep 17 00:00:00 2001 From: monojenkins Date: Fri, 4 Sep 2020 14:56:21 -0400 Subject: [PATCH] [Android] Enable access to up-to-date tzdata on Android 10+ (#20350) Context: https://source.android.com/devices/architecture/modular-system/runtime#time-zone-data-interactions Context: https://source.android.com/devices/tech/config/timezone-rules#timezone-apex Maybe Fixes: https://github.com/xamarin/xamarin-android/issues/5080 Add support to read ICANN timezone data from two new locations found on devices running Android 10+. The data in the previously searched location still exists but it's most likely out of date. On Android 10+ tzdata updates will be derived via an APEX TimeData package update, whose data directory this commit sets as the first location to be searched. This commit potentially fixes the Xamarin.Android issue mentioned above. "Potentially" because I can't be sure this is what's causing it since I'm unable to reproduce the issue locally. However, out-of-date tz database seems to be the most probable cause. Co-authored-by: Marek Habersack --- mcs/class/corlib/System/TimeZoneInfo.Android.cs | 26 +++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/mcs/class/corlib/System/TimeZoneInfo.Android.cs b/mcs/class/corlib/System/TimeZoneInfo.Android.cs index fa9f73a4dc6..792a9fe2bc3 100644 --- a/mcs/class/corlib/System/TimeZoneInfo.Android.cs +++ b/mcs/class/corlib/System/TimeZoneInfo.Android.cs @@ -58,10 +58,16 @@ namespace System { * https://android.googlesource.com/platform/libcore/+/master/luni/src/main/java/libcore/util/ZoneInfoDB.java * * This is needed in order to read Android v4.3 tzdata files. + * + * Android 10+ moved the up-to-date tzdata location to a module updatable via the Google Play Store and the + * database location changed (https://source.android.com/devices/architecture/modular-system/runtime#time-zone-data-interactions) + * The older locations still exist (at least the `/system/usr/share/zoneinfo` one) but they won't be updated. */ sealed class AndroidTzData : IAndroidTimeZoneDB { internal static readonly string[] Paths = new string[]{ + GetApexTimeDataRoot () + "/etc/tz/tzdata", // Android 10+, TimeData module where the updates land + GetApexRuntimeRoot () + "/etc/tz/tzdata", // Android 10+, Fallback location if the above isn't found or corrupted Environment.GetEnvironmentVariable ("ANDROID_DATA") + "/misc/zoneinfo/tzdata", Environment.GetEnvironmentVariable ("ANDROID_ROOT") + "/usr/share/zoneinfo/tzdata", }; @@ -98,6 +104,26 @@ namespace System { get {return zoneTab;} } + static string GetApexTimeDataRoot () + { + string ret = Environment.GetEnvironmentVariable ("ANDROID_TZDATA_ROOT"); + if (!String.IsNullOrEmpty (ret)) { + return ret; + } + + return "/apex/com.android.tzdata"; + } + + static string GetApexRuntimeRoot () + { + string ret = Environment.GetEnvironmentVariable ("ANDROID_RUNTIME_ROOT"); + if (!String.IsNullOrEmpty (ret)) { + return ret; + } + + return "/apex/com.android.runtime"; + } + bool LoadData (string path) { if (!File.Exists (path)) -- 2.11.4.GIT