1 files changed, 161 insertions, 0 deletions
diff --git a/src/mscorlib/src/System/CompatibilitySwitches.cs b/src/mscorlib/src/System/CompatibilitySwitches.cs
new file mode 100644
index 0000000000..59668fd13a
--- /dev/null
+++ b/src/mscorlib/src/System/CompatibilitySwitches.cs
@@ -0,0 +1,161 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+
+using System.Runtime;
+using System.Runtime.CompilerServices;
+
+namespace System
+{
+    [FriendAccessAllowed]
+    internal static class CompatibilitySwitches
+    {
+        private static bool s_AreSwitchesSet;
+
+#if FEATURE_LEGACYNETCF
+        private static bool s_isAppEarlierThanWindowsPhone8;
+        private static bool s_isAppEarlierThanWindowsPhoneMango;
+#endif //FEATURE_LEGACYNETCF
+
+#if FEATURE_CORECLR
+        private static bool s_isAppSilverlight81;  // The app targets SL8.1 version
+        private static bool s_useLatestBehaviorWhenTFMNotSpecified; // Which behavior to use when the TFM is not specified.
+#endif //FEATURE_CORECLR
+
+#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
+            s_isAppSilverlight81 = IsCompatibilitySwitchSet("WindowsPhone_5.1.0.0");
+            s_useLatestBehaviorWhenTFMNotSpecified = IsCompatibilitySwitchSet("UseLatestBehaviorWhenTFMNotSpecified");
+#endif //FEATURE_CORECLR
+
+#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
+        {
+            get
+            {
+                return false;
+            }
+        }
+
+#if FEATURE_CORECLR
+        /// <summary>
+        /// This property returns whether the app is hosted under SL 8.1 version
+        /// </summary>
+        internal static bool IsAppSilverlight81
+        {
+            get
+            {
+                // PS - Do not use this property for adding quirks. Please use the exposed properties of BinaryCompatiblity class instead.
+                return s_isAppSilverlight81;
+            }
+        }
+
+        /// <summary>
+        /// This property returns whether to give the latest behavior when the TFM is missing
+        /// </summary>
+        internal static bool UseLatestBehaviorWhenTFMNotSpecified
+        {
+            get
+            {
+                return s_useLatestBehaviorWhenTFMNotSpecified;
+            }
+        }
+#endif //FEATURE_CORECLR
+
+        public static bool IsAppEarlierThanWindowsPhone8
+        {
+            get
+            {
+#if FEATURE_LEGACYNETCF
+                return s_isAppEarlierThanWindowsPhone8;
+#else
+                return false;
+#endif //FEATURE_LEGACYNETCF
+            }
+        }
+
+        public static bool IsAppEarlierThanWindowsPhoneMango
+        {
+            get
+            {
+#if FEATURE_LEGACYNETCF
+                return s_isAppEarlierThanWindowsPhoneMango;
+#else
+                return false;
+#endif //FEATURE_LEGACYNETCF
+            }
+        }
+
+        public static bool IsNetFx40TimeSpanLegacyFormatMode
+        {
+            get
+            {
+#if !FEATURE_CORECLR
+                return s_isNetFx40TimeSpanLegacyFormatMode;
+#else
+                return false;
+#endif //!FEATURE_CORECLR
+            }
+        }
+
+        public static bool IsNetFx40LegacySecurityPolicy
+        {
+            get
+            {
+#if !FEATURE_CORECLR
+                return s_isNetFx40LegacySecurityPolicy;
+#else
+                return false;
+#endif //!FEATURE_CORECLR
+            }
+        }
+
+        public static bool IsNetFx45LegacyManagedDeflateStream
+        {
+            get
+            {
+#if !FEATURE_CORECLR
+                return s_isNetFx45LegacyManagedDeflateStream;
+#else
+                return false;
+#endif //!FEATURE_CORECLR
+            }
+        }
+    }
+}