Imported Upstream version 4.0.0~alpha1

Former-commit-id: 806294f5ded97629b74c85c09952f2a74fe182d9

external/referencesource/mscorlib/system/compatibilityswitches.cs

@@ -0,0 +1,157 @@
+// ==++==
+//
+//   Copyright (c) Microsoft Corporation.  All rights reserved.
+//
+// ==--==
+
+using System.Runtime;
+using System.Runtime.CompilerServices;
+
+namespace System
+{
+    [FriendAccessAllowed]
+    internal static class CompatibilitySwitches
+    {
+        private static bool s_AreSwitchesSet;
+#if FEATURE_CORECLR && !FEATURE_CORESYSTEM
+        private static bool s_isAppEarlierThanSilverlight4;
+#endif //FEATURE_CORECLR && !FEATURE_CORESYSTEM
+
+#if FEATURE_LEGACYNETCF
+        private static bool s_isAppEarlierThanWindowsPhone8;
+        private static bool s_isAppEarlierThanWindowsPhoneMango;
+#endif //FEATURE_LEGACYNETCF
+
+#if !FEATURE_CORECLR
+        private static bool s_isNetFx40TimeSpanLegacyFormatMode;
+        private static bool s_isNetFx40LegacySecurityPolicy;
+        private static bool s_isNetFx45LegacyManagedDeflateStream;
+#endif //!FEATURE_CORECLR
+
+        public static bool IsCompatibilityBehaviorDefined
+        {
+            get
+            {
+                return s_AreSwitchesSet;
+            }
+        }
+
+        private static bool IsCompatibilitySwitchSet(string compatibilitySwitch)
+        {
+            bool? result = AppDomain.CurrentDomain.IsCompatibilitySwitchSet(compatibilitySwitch);
+            return (result.HasValue && result.Value);
+        }
+
+        internal static void InitializeSwitches()
+        {
+#if FEATURE_CORECLR && !FEATURE_CORESYSTEM
+            s_isAppEarlierThanSilverlight4 = IsCompatibilitySwitchSet("APP_EARLIER_THAN_SL4.0");
+#endif //FEATURE_CORECLR && !FEATURE_CORESYSTEM
+
+#if FEATURE_LEGACYNETCF
+            s_isAppEarlierThanWindowsPhoneMango = IsCompatibilitySwitchSet("WindowsPhone_3.7.0.0");
+            s_isAppEarlierThanWindowsPhone8 = s_isAppEarlierThanWindowsPhoneMango || 
+                                                IsCompatibilitySwitchSet("WindowsPhone_3.8.0.0"); 
+                    
+#endif //FEATURE_LEGACYNETCF
+
+#if !FEATURE_CORECLR
+            s_isNetFx40TimeSpanLegacyFormatMode = IsCompatibilitySwitchSet("NetFx40_TimeSpanLegacyFormatMode");
+            s_isNetFx40LegacySecurityPolicy = IsCompatibilitySwitchSet("NetFx40_LegacySecurityPolicy");
+            s_isNetFx45LegacyManagedDeflateStream = IsCompatibilitySwitchSet("NetFx45_LegacyManagedDeflateStream");
+#endif //FEATURE_CORECLR
+
+            s_AreSwitchesSet = true;
+        }
+
+        public static bool IsAppEarlierThanSilverlight4
+        {
+#if !FEATURE_CORECLR
+            [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
+#endif
+            get
+            {
+#if FEATURE_CORECLR && !FEATURE_CORESYSTEM
+                return s_isAppEarlierThanSilverlight4;
+#else
+                return false;
+#endif //FEATURE_CORECLR && !FEATURE_CORESYSTEM
+            }
+        }
+
+        public static bool IsAppEarlierThanWindowsPhone8
+        {
+#if !FEATURE_CORECLR
+            [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
+#endif
+            get
+            {
+#if FEATURE_LEGACYNETCF
+                return s_isAppEarlierThanWindowsPhone8;
+#else
+                return false;
+#endif //FEATURE_LEGACYNETCF
+            }
+        }
+
+        public static bool IsAppEarlierThanWindowsPhoneMango
+        {
+#if !FEATURE_CORECLR
+            [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
+#endif
+            get
+            {
+#if FEATURE_LEGACYNETCF
+                return s_isAppEarlierThanWindowsPhoneMango;
+#else
+                return false;
+#endif //FEATURE_LEGACYNETCF
+            }
+        }
+
+        public static bool IsNetFx40TimeSpanLegacyFormatMode
+        {
+#if !FEATURE_CORECLR
+            [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
+#endif
+            get
+            {
+#if !FEATURE_CORECLR
+                return s_isNetFx40TimeSpanLegacyFormatMode;
+#else
+                return false;
+#endif //!FEATURE_CORECLR
+            }
+        }
+
+        public static bool IsNetFx40LegacySecurityPolicy
+        {
+#if !FEATURE_CORECLR
+            [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
+#endif
+            get
+            {
+#if !FEATURE_CORECLR
+                return s_isNetFx40LegacySecurityPolicy;
+#else
+                return false;
+#endif //!FEATURE_CORECLR
+            }
+        }
+
+        public static bool IsNetFx45LegacyManagedDeflateStream
+        {
+#if !FEATURE_CORECLR
+            [TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
+#endif
+            get
+            {
+#if !FEATURE_CORECLR
+                return s_isNetFx45LegacyManagedDeflateStream;
+#else
+                return false;
+#endif //!FEATURE_CORECLR
+            }
+        }
+    }
+}