Move DateTime for Unix to shared partition (#22383)

* Move DateTime for Unix to shared partition

* Keep CoreCLR specific implementation

5 files changed, 29 insertions, 11 deletions

diff --git a/src/System.Private.CoreLib/System.Private.CoreLib.csproj b/src/System.Private.CoreLib/System.Private.CoreLib.csproj
index feabb1d9a3..2feaaa25f8 100644
--- a/src/System.Private.CoreLib/System.Private.CoreLib.csproj
+++ b/src/System.Private.CoreLib/System.Private.CoreLib.csproj
@@ -355,8 +355,8 @@
     <Compile Include="$(BclSourcesRoot)\System\Variant.cs" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsUnix)' == 'true'">
-    <Compile Include="$(BclSourcesRoot)\System\DateTime.Unix.cs" />
     <Compile Include="$(BclSourcesRoot)\Interop\Unix\Interop.Libraries.cs" />
+    <Compile Include="$(BclSourcesRoot)\System\DateTime.Unix.CoreCLR.cs" />
     <Compile Include="$(BclSourcesRoot)\System\Globalization\GlobalizationMode.Unix.cs" />
     <Compile Include="$(BclSourcesRoot)\System\Threading\ClrThreadPoolBoundHandle.Unix.cs" />
   </ItemGroup>
diff --git a/src/System.Private.CoreLib/shared/Interop/Unix/System.Native/Interop.GetSystemTimeAsTicks.cs b/src/System.Private.CoreLib/shared/Interop/Unix/System.Native/Interop.GetSystemTimeAsTicks.cs
index d33b3f3685..f02ecac13b 100644
--- a/src/System.Private.CoreLib/shared/Interop/Unix/System.Native/Interop.GetSystemTimeAsTicks.cs
+++ b/src/System.Private.CoreLib/shared/Interop/Unix/System.Native/Interop.GetSystemTimeAsTicks.cs
@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
 internal static partial class Interop
diff --git a/src/System.Private.CoreLib/shared/System.Private.CoreLib.Shared.projitems b/src/System.Private.CoreLib/shared/System.Private.CoreLib.Shared.projitems
index b44cc1e31f..8063228b62 100644
--- a/src/System.Private.CoreLib/shared/System.Private.CoreLib.Shared.projitems
+++ b/src/System.Private.CoreLib/shared/System.Private.CoreLib.Shared.projitems
@@ -1138,6 +1138,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Unix\System.Native\Interop.Write.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Internal\IO\File.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Microsoft\Win32\SafeHandles\SafeFileHandle.Unix.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\DateTime.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebugProvider.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Environment.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\CalendarData.Unix.cs" />
diff --git a/src/System.Private.CoreLib/src/System/DateTime.Unix.cs b/src/System.Private.CoreLib/shared/System/DateTime.Unix.cs
index f5982fab69..6cf018115b 100644
--- a/src/System.Private.CoreLib/src/System/DateTime.Unix.cs
+++ b/src/System.Private.CoreLib/shared/System/DateTime.Unix.cs
@@ -2,29 +2,26 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System.Runtime.CompilerServices;
-
 namespace System
 {
     public readonly partial struct DateTime
     {
         internal const bool s_systemSupportsLeapSeconds = false;
 
+#if !CORECLR
         public static DateTime UtcNow
         {
             get
             {
-                return new DateTime(((ulong)(GetSystemTimeAsFileTime() + FileTimeOffset)) | KindUtc);
+                return new DateTime(((ulong)(Interop.Sys.GetSystemTimeAsTicks() + UnixEpochTicks)) | KindUtc);
             }
         }
+#endif
 
-        internal static DateTime FromFileTimeLeapSecondsAware(long fileTime) => default(DateTime);
-        internal static long ToFileTimeLeapSecondsAware(long ticks) => default(long);
+        internal static DateTime FromFileTimeLeapSecondsAware(long fileTime) => default;
+        internal static long ToFileTimeLeapSecondsAware(long ticks) => default;
 
         // IsValidTimeWithLeapSeconds is not expected to be called at all for now on non-Windows platforms
         internal static bool IsValidTimeWithLeapSeconds(int year, int month, int day, int hour, int minute, int second, DateTimeKind kind) => false;
-
-        [MethodImplAttribute(MethodImplOptions.InternalCall)]
-        internal static extern long GetSystemTimeAsFileTime();
     }
 }
diff --git a/src/System.Private.CoreLib/src/System/DateTime.Unix.CoreCLR.cs b/src/System.Private.CoreLib/src/System/DateTime.Unix.CoreCLR.cs
new file mode 100644
index 0000000000..1fd1e9ca40
--- /dev/null
+++ b/src/System.Private.CoreLib/src/System/DateTime.Unix.CoreCLR.cs
@@ -0,0 +1,22 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.CompilerServices;
+
+namespace System
+{
+    public readonly partial struct DateTime
+    {
+        public static DateTime UtcNow
+        {
+            get
+            {
+                return new DateTime(((ulong)(GetSystemTimeAsFileTime() + FileTimeOffset)) | KindUtc);
+            }
+        }
+
+        [MethodImplAttribute(MethodImplOptions.InternalCall)]
+        private static extern long GetSystemTimeAsFileTime();
+    }
+}
\ No newline at end of file