mcs/class/referencesource/mscorlib/system/AppContext/AppContextSwitches.cs

   1 // ==++==
   2 //
   3 //   Copyright (c) Microsoft Corporation.  All rights reserved.
   4 //
   5 // ==--==
   6
   7 namespace System
   8 {
   9     using System;
  10     using System.Runtime.CompilerServices;
  11
  12     internal static class AppContextSwitches
  13     {
  14         private static int _noAsyncCurrentCulture;
  15         public static bool NoAsyncCurrentCulture
  16         {
  17             [MethodImpl(MethodImplOptions.AggressiveInlining)]
  18             get
  19             {
  20                 return GetCachedSwitchValue(AppContextDefaultValues.SwitchNoAsyncCurrentCulture, ref _noAsyncCurrentCulture);
  21             }
  22         }
  23
  24         private static int _throwExceptionIfDisposedCancellationTokenSource;
  25         public static bool ThrowExceptionIfDisposedCancellationTokenSource
  26         {
  27             [MethodImpl(MethodImplOptions.AggressiveInlining)]
  28             get
  29             {
  30                 return GetCachedSwitchValue(AppContextDefaultValues.SwitchThrowExceptionIfDisposedCancellationTokenSource, ref _throwExceptionIfDisposedCancellationTokenSource);
  31             }
  32         }
  33
  34         private static int _preserveEventListnerObjectIdentity;
  35         public static bool PreserveEventListnerObjectIdentity
  36         {
  37             [MethodImpl(MethodImplOptions.AggressiveInlining)]
  38             get
  39             {
  40                 return GetCachedSwitchValue(AppContextDefaultValues.SwitchPreserveEventListnerObjectIdentity, ref _preserveEventListnerObjectIdentity);
  41             }
  42         }
  43
  44         private static int _useLegacyPathHandling;
  45
  46         /// <summary>
  47         /// Use legacy path normalization logic and blocking of extended syntax.
  48         /// </summary>
  49         public static bool UseLegacyPathHandling
  50         {
  51             [MethodImpl(MethodImplOptions.AggressiveInlining)]
  52             get
  53             {
  54                 return GetCachedSwitchValue(AppContextDefaultValues.SwitchUseLegacyPathHandling, ref _useLegacyPathHandling);
  55             }
  56         }
  57
  58         private static int _blockLongPaths;
  59
  60         /// <summary>
  61         /// Throw PathTooLongException for paths greater than MAX_PATH or directories greater than 248 (as per CreateDirectory Win32 limitations)
  62         /// </summary>
  63         public static bool BlockLongPaths
  64         {
  65             [MethodImpl(MethodImplOptions.AggressiveInlining)]
  66             get
  67             {
  68                 return GetCachedSwitchValue(AppContextDefaultValues.SwitchBlockLongPaths, ref _blockLongPaths);
  69             }
  70         }
  71
  72         private static int _cloneActor;
  73
  74         /// <summary>
  75         /// When copying a ClaimsIdentity.Actor this switch controls whether ClaimsIdentity.Actor should be set as a reference or the result of Actor.Clone()
  76         /// </summary>
  77         public static bool SetActorAsReferenceWhenCopyingClaimsIdentity
  78         {
  79             [MethodImpl(MethodImplOptions.AggressiveInlining)]
  80             get
  81             {
  82                 return GetCachedSwitchValue(AppContextDefaultValues.SwitchSetActorAsReferenceWhenCopyingClaimsIdentity, ref _cloneActor);
  83             }
  84         }
  85
  86         //
  87         // Implementation details
  88         //
  89
  90         private static bool DisableCaching { get; set; }
  91
  92         static AppContextSwitches()
  93         {
  94             bool isEnabled;
  95             if (AppContext.TryGetSwitch(@"TestSwitch.LocalAppContext.DisableCaching", out isEnabled))
  96             {
  97                 DisableCaching = isEnabled;
  98             }
  99         }
 100
 101         [MethodImpl(MethodImplOptions.AggressiveInlining)]
 102         internal static bool GetCachedSwitchValue(string switchName, ref int switchValue)
 103         {
 104             if (switchValue < 0) return false;
 105             if (switchValue > 0) return true;
 106
 107             return GetCachedSwitchValueInternal(switchName, ref switchValue);
 108         }
 109
 110         private static bool GetCachedSwitchValueInternal(string switchName, ref int switchValue)
 111         {
 112             bool isSwitchEnabled;
 113             AppContext.TryGetSwitch(switchName, out isSwitchEnabled);
 114
 115             if (DisableCaching)
 116             {
 117                 return isSwitchEnabled;
 118             }
 119
 120             switchValue = isSwitchEnabled ? 1 /*true*/ : -1 /*false*/;
 121             return isSwitchEnabled;
 122         }
 123     }
 124 }