mcs/class/referencesource/mscorlib/system/runtime/remoting/contextproperty.cs

   1 // ==++==
   2 //
   3 //   Copyright (c) Microsoft Corporation.  All rights reserved.
   4 //
   5 // ==--==
   6 /*============================================================
   7 **
   8 ** File:    ContextProperty.cs
   9 **
  10 ** A contextProperty is a name-value pair holding the property
  11 ** name and the object representing the property in a context.
  12 ** An array of these is returned by Context::GetContextProperties()
  13 **
  14 **
  15 **
  16 ===========================================================*/
  17
  18 namespace System.Runtime.Remoting.Contexts {
  19
  20     using System;
  21     using System.Threading;
  22     using System.Reflection;
  23     using System.Runtime.InteropServices;
  24     using System.Runtime.CompilerServices;
  25     using System.Runtime.Remoting.Activation;
  26     using System.Security.Permissions;
  27     using System.Diagnostics.Contracts;
  28
  29     /// <internalonly/>
  30     [System.Security.SecurityCritical]  // auto-generated_required
  31     [SecurityPermissionAttribute(SecurityAction.InheritanceDemand, Flags=SecurityPermissionFlag.Infrastructure)]
  32     [System.Runtime.InteropServices.ComVisible(true)]
  33     public class ContextProperty {
  34         internal String _name;           // property name
  35         internal Object _property;       // property object
  36
  37     /// <internalonly/>
  38         public virtual String Name {
  39             get {
  40                 return _name;
  41             }
  42         }
  43
  44     /// <internalonly/>
  45         public virtual Object Property {
  46             get {
  47                 return _property;
  48             }
  49         }
  50
  51         /* can't create outside the package */
  52         internal ContextProperty(String name, Object prop)
  53         {
  54             _name = name;
  55             _property = prop;
  56         }
  57     }
  58
  59     //  The IContextAttribute interface is implemented by attribute classes.
  60     //  The attributes contribute a property which resides in a context and
  61     //  enforces a specific policy for the objects created in that context.
  62     /// <internalonly/>
  63 [System.Runtime.InteropServices.ComVisible(true)]
  64     public interface IContextAttribute
  65     {
  66     /// <internalonly/>
  67         [System.Security.SecurityCritical]  // auto-generated_required
  68         bool IsContextOK(Context ctx, IConstructionCallMessage msg);
  69     /// <internalonly/>
  70         [System.Security.SecurityCritical]  // auto-generated_required
  71         void GetPropertiesForNewContext(IConstructionCallMessage msg);
  72     }
  73
  74    //   This interface is exposed by the property contributed to a context
  75    //   by an attribute. By default, it is also implemented by the ContextAttribute
  76    //   base class which every attribute class must extend from.
  77     /// <internalonly/>
  78 [System.Runtime.InteropServices.ComVisible(true)]
  79     public interface IContextProperty
  80     {
  81     /// <internalonly/>
  82        //   This is the name under which the property will be added
  83        //   to the {name,property} table in a context.
  84         String Name
  85         {
  86             [System.Security.SecurityCritical]  // auto-generated_required
  87             get;
  88         }
  89     /// <internalonly/>
  90        //   After forming the newCtx, we ask each property if it is happy
  91        //   with the context. We expect most implementations to say yes.
  92         [System.Security.SecurityCritical]  // auto-generated_required
  93         bool IsNewContextOK(Context newCtx);
  94     /// <internalonly/>
  95
  96         // New method. All properties are notified when the context
  97         // they are in is frozen.
  98         [System.Security.SecurityCritical]  // auto-generated_required
  99         void Freeze(Context newContext);
 100     }
 101
 102     /// <internalonly/>
 103 [System.Runtime.InteropServices.ComVisible(true)]
 104     public interface IContextPropertyActivator
 105     {
 106     /// <internalonly/>
 107         // This method lets properties in the current context have a say in
 108         // whether an activation may be done 'here' or not.
 109         [System.Security.SecurityCritical]  // auto-generated_required
 110         bool IsOKToActivate(IConstructionCallMessage msg);
 111     /// <internalonly/>
 112         [System.Security.SecurityCritical]  // auto-generated_required
 113         void CollectFromClientContext(IConstructionCallMessage msg);
 114     /// <internalonly/>
 115         [System.Security.SecurityCritical]  // auto-generated_required
 116         bool DeliverClientContextToServerContext(IConstructionCallMessage msg);
 117     /// <internalonly/>
 118         [System.Security.SecurityCritical]  // auto-generated_required
 119         void CollectFromServerContext(IConstructionReturnMessage msg);
 120     /// <internalonly/>
 121         [System.Security.SecurityCritical]  // auto-generated_required
 122         bool DeliverServerContextToClientContext(IConstructionReturnMessage msg);
 123     }
 124
 125
 126    //   All context attribute classes must extend from this base class.
 127    //   This class provides the base implementations which the derived
 128    //   classes are free to over-ride. The base implementations provide
 129    //   the default answers to various questions.
 130
 131     /// <internalonly/>
 132     [System.Security.SecurityCritical]  // auto-generated_required
 133     [Serializable]
 134     [AttributeUsage(AttributeTargets.Class)]
 135     [SecurityPermissionAttribute(SecurityAction.InheritanceDemand, Flags=SecurityPermissionFlag.Infrastructure)]
 136     [System.Runtime.InteropServices.ComVisible(true)]
 137     public class ContextAttribute
 138         : Attribute, IContextAttribute, IContextProperty
 139     {
 140     /// <internalonly/>
 141         protected String AttributeName;
 142
 143         // The derived class must call: base(name);
 144     /// <internalonly/>
 145         public ContextAttribute(String name)
 146         {
 147             AttributeName = name;
 148         }
 149
 150         // IContextPropery::Name
 151         // Default implementation provides AttributeName as the property name.
 152     /// <internalonly/>
 153         public virtual String Name
 154         {
 155             [System.Security.SecurityCritical]
 156             get { return AttributeName; }
 157         }
 158
 159         // IContextProperty::IsNewContextOK
 160     /// <internalonly/>
 161         [System.Security.SecurityCritical]
 162         public virtual bool IsNewContextOK(Context newCtx)
 163         {
 164             // This will be called before entering the newCtx
 165             // Default implementation says OK.
 166             return true;
 167         }
 168
 169         // IContextProperty::Freeze
 170         // Default implementation does nothing
 171     /// <internalonly/>
 172         [System.Security.SecurityCritical]
 173         public virtual void Freeze(Context newContext)
 174         {
 175             BCLDebug.Log("ContextAttribute::ContextProperty::Freeze"+
 176                         " for context " + newContext );
 177         }
 178
 179         // Object::Equals
 180         // Default implementation just compares the names
 181     /// <internalonly/>
 182         [System.Security.SecuritySafeCritical] // overrides public transparent method
 183         public override bool Equals(Object o)
 184         {
 185             IContextProperty prop = o as IContextProperty;
 186             return  (null != prop) && AttributeName.Equals(prop.Name);
 187         }
 188
 189     /// <internalonly/>
 190         [System.Security.SecuritySafeCritical] // overrides public transparent method
 191         public override int GetHashCode()
 192         {
 193             return this.AttributeName.GetHashCode();
 194         }
 195
 196         // IContextAttribute::IsContextOK
 197         // Default calls Object::Equals on the property and does not
 198         // bother with the ctorMsg.
 199     /// <internalonly/>
 200         [System.Security.SecurityCritical]  // auto-generated
 201         public virtual bool IsContextOK(
 202             Context ctx, IConstructionCallMessage ctorMsg)
 203         {
 204             if (ctx == null)
 205                 throw new ArgumentNullException("ctx");
 206             if (ctorMsg == null)
 207                 throw new ArgumentNullException("ctorMsg");
 208             Contract.EndContractBlock();
 209
 210             Contract.Assert(ctorMsg.ActivationType.IsMarshalByRef, "Activation on a non MarshalByRef object");
 211
 212             if (!ctorMsg.ActivationType.IsContextful)
 213             {
 214                 return true;
 215             }
 216
 217             Object prop = ctx.GetProperty(AttributeName);
 218             if ((prop!=null) && (Equals(prop)))
 219             {
 220                 return true;
 221             }
 222             return false;
 223         }
 224
 225         // IContextAttribute::GetPropertiesForNewContext
 226         // Default adds the attribute itself w/o regard to the current
 227         // list of properties
 228     /// <internalonly/>
 229         [System.Security.SecurityCritical]  // auto-generated
 230         public virtual void GetPropertiesForNewContext(
 231             IConstructionCallMessage ctorMsg)
 232         {
 233             if (ctorMsg == null)
 234                 throw new ArgumentNullException("ctorMsg");
 235             Contract.EndContractBlock();
 236             ctorMsg.ContextProperties.Add((IContextProperty)this);
 237         }
 238     }
 239
 240 #if SIMPLEXAACTIVATION
 241     /// <internalonly/>
 242         [AttributeUsage(AttributeTargets.Class)]
 243 [System.Runtime.InteropServices.ComVisible(true)]
 244     public class new_appdomain : ContextAttribute
 245     {
 246
 247         internal static int _domain_no = 0;
 248
 249     /// <internalonly/>
 250         public new_appdomain() : base("new_appdomain") {}
 251
 252     /// <internalonly/>
 253 [System.Runtime.InteropServices.ComVisible(true)]
 254         public override bool IsContextOK(Context ctx, IConstructionCallMessage msg)
 255         {
 256             return false;
 257         }
 258
 259     /// <internalonly/>
 260 [System.Runtime.InteropServices.ComVisible(true)]
 261         public override void GetPropertiesForNewContext(IConstructionCallMessage ctorMsg)
 262         {
 263             ctorMsg.GetProperties()["__new_appdomain"] = true;
 264         }
 265
 266     /// <internalonly/>
 267 [System.Runtime.InteropServices.ComVisible(true)]
 268         public static IConstructionReturnMessage DoSimpleXADActivation(IConstructionCallMessage msg)
 269         {
 270             int domain_no = Interlocked.Increment(ref _domain_no);
 271             AppDomain ad = AppDomain.CreateDomain("AutoDomain #" + domain_no, null, null);
 272
 273             activator a = (activator) (ad.CreateInstance(null, typeof(activator).FullName)).Unwrap();
 274
 275             return a.Activate(msg);
 276         }
 277
 278     /// <internalonly/>
 279 [System.Runtime.InteropServices.ComVisible(true)]
 280         public class activator : MarshalByRefObject, IActivator
 281         {
 282         /// <internalonly/>
 283 [System.Runtime.InteropServices.ComVisible(true)]
 284             public IConstructionReturnMessage Activate(IConstructionCallMessage msg)
 285             {
 286                 return RemotingServices.DoCrossContextActivation(msg);
 287             }
 288
 289         /// <internalonly/>
 290             [MethodImplAttribute(MethodImplOptions.NoInlining)] // Methods containing StackCrawlMark local var has to be marked non-inlineable
 291             public void LoadAssembly(AssemblyName an)
 292             {
 293                 StackCrawlMark stackMark = StackCrawlMark.LookForMyCaller;
 294                 Assembly a = Assembly.InternalLoad(an, false, null, ref stackMark);
 295                 if (a == null)
 296                 {
 297                     throw new RemotingException(
 298                         String.Format(
 299                             Environment.GetResourceString(
 300                                 "Remoting_AssemblyLoadFailed"),
 301                             an));
 302                 }
 303             }
 304         }
 305     }
 306
 307     /// <internalonly/>
 308         [new_appdomain]
 309 [System.Runtime.InteropServices.ComVisible(true)]
 310         public class MBR : MarshalByRefObject
 311         {
 312         /// <internalonly/>
 313             public String MyAppDomain()
 314             {
 315                 return Thread.GetDomain().GetFriendlyName();
 316             }
 317         }
 318
 319     /// <internalonly/>
 320         [new_appdomain]
 321 [System.Runtime.InteropServices.ComVisible(true)]
 322         public class CB : ContextBoundObject
 323         {
 324         /// <internalonly/>
 325             public String MyAppDomain()
 326             {
 327                 return Thread.GetDomain().GetFriendlyName();
 328             }
 329         }
 330 #endif
 331
 332 }