summaryrefslogtreecommitdiff
path: root/src/mscorlib/shared/System/Runtime/Serialization
diff options
context:
space:
mode:
Diffstat (limited to 'src/mscorlib/shared/System/Runtime/Serialization')
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/IDeserializationCallback.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/IFormatterConverter.cs28
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/IObjectReference.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/ISafeSerializationData.cs207
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/ISerializable.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/OnDeserializedAttribute.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/OnDeserializingAttribute.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/OnSerializedAttribute.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/OnSerializingAttribute.cs11
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/OptionalFieldAttribute.cs25
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/SafeSerializationEventArgs.cs31
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/SerializationException.cs39
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/SerializationInfoEnumerator.cs127
-rw-r--r--src/mscorlib/shared/System/Runtime/Serialization/StreamingContext.cs53
14 files changed, 587 insertions, 0 deletions
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/IDeserializationCallback.cs b/src/mscorlib/shared/System/Runtime/Serialization/IDeserializationCallback.cs
new file mode 100644
index 0000000000..a1c1671a8b
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/IDeserializationCallback.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ public interface IDeserializationCallback
+ {
+ void OnDeserialization(object sender);
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/IFormatterConverter.cs b/src/mscorlib/shared/System/Runtime/Serialization/IFormatterConverter.cs
new file mode 100644
index 0000000000..c173144854
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/IFormatterConverter.cs
@@ -0,0 +1,28 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [CLSCompliant(false)]
+ public interface IFormatterConverter
+ {
+ object Convert(object value, Type type);
+ object Convert(object value, TypeCode typeCode);
+ bool ToBoolean(object value);
+ char ToChar(object value);
+ sbyte ToSByte(object value);
+ byte ToByte(object value);
+ short ToInt16(object value);
+ ushort ToUInt16(object value);
+ int ToInt32(object value);
+ uint ToUInt32(object value);
+ long ToInt64(object value);
+ ulong ToUInt64(object value);
+ float ToSingle(object value);
+ double ToDouble(object value);
+ decimal ToDecimal(object value);
+ DateTime ToDateTime(object value);
+ string ToString(object value);
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/IObjectReference.cs b/src/mscorlib/shared/System/Runtime/Serialization/IObjectReference.cs
new file mode 100644
index 0000000000..d41bc50dde
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/IObjectReference.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ public interface IObjectReference
+ {
+ object GetRealObject(StreamingContext context);
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/ISafeSerializationData.cs b/src/mscorlib/shared/System/Runtime/Serialization/ISafeSerializationData.cs
new file mode 100644
index 0000000000..5089d134c3
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/ISafeSerializationData.cs
@@ -0,0 +1,207 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ //
+ // #SafeSerialization
+ //
+ // Types which are serializable via the ISerializable interface have a problem when it comes to allowing
+ // transparent subtypes which can allow themselves to serialize since the GetObjectData method is
+ // SecurityCritical.
+ //
+ // For instance, System.Exception implements ISerializable, however it is also desirable to have
+ // transparent exceptions with their own fields that need to be serialized. (For instance, in transparent
+ // assemblies such as the DLR and F#, or even in partial trust application code). Since overriding
+ // GetObjectData requires that the overriding method be security critical, this won't work directly.
+ //
+ // SafeSerializationManager solves this problem by allowing any partial trust code to contribute
+ // individual chunks of serializable data to be included in the serialized version of the derived class.
+ // These chunks are then deserialized back out of the serialized type and notified that they should
+ // populate the fields of the deserialized object when serialization is complete. This allows partial
+ // trust or transparent code to participate in serialization of an ISerializable type without having to
+ // override GetObjectData or implement the ISerializable constructor.
+ //
+ // On the serialization side, SafeSerializationManager has an event SerializeObjectState which it will
+ // fire in response to serialization in order to gather the units of serializable data that should be
+ // stored with the rest of the object during serialization. Methods which respond to these events
+ // create serializable objects which implement the ISafeSerializationData interface and add them to the
+ // collection of other serialized data by calling AddSerializedState on the SafeSerializationEventArgs
+ // passed into the event.
+ //
+ // By using an event rather than a virtual method on the base ISerializable object, we allow multiple
+ // potentially untrusted subclasses to participate in serialization, without each one having to ensure
+ // that it calls up to the base type in order for the whole system to work. (For instance Exception :
+ // TrustedException : UntrustedException, in this scenario UntrustedException would be able to override
+ // the virtual method an prevent TrustedException from ever seeing the method call, either accidentally
+ // or maliciously).
+ //
+ // Further, by only allowing additions of new chunks of serialization state rather than exposing the
+ // whole underlying list, we avoid exposing potentially sensitive serialized state to any of the
+ // potentially untrusted subclasses.
+ //
+ // At deserialization time, SafeSerializationManager performs the reverse operation. It deserializes the
+ // chunks of serialized state, and then notifies them that the object they belong to is deserialized by
+ // calling their CompleteSerialization method. In repsonse to this call, the state objects populate the
+ // fields of the object being deserialized with the state that they held.
+ //
+ // From a security perspective, the chunks of serialized state can only contain data that the specific
+ // subclass itself had access to read (otherwise it wouldn't be able to populate the type with that
+ // data), as opposed to having access to far more data in the SerializationInfo that GetObjectData uses.
+ // Similarly, at deserialization time, the serialized state can only modify fields that the type itself
+ // has access to (again, as opposed to the full SerializationInfo which could be modified).
+ //
+ // Individual types which wish to participate in safe serialization do so by containing an instance of a
+ // SafeSerializationManager and exposing its serialization event. During GetObjectData, the
+ // SafeSerializationManager is serialized just like any other field of the containing type. However, at
+ // the end of serialization it is called back one last time to CompleteSerialization.
+ //
+ // In CompleteSerialization, if the SafeSerializationManager detects that it has extra chunks of
+ // data to handle, it substitutes the root type being serialized (formerly the real type hosting the
+ // SafeSerializationManager) with itself. This allows it to gain more control over the deserialization
+ // process. It also saves away an extra bit of state in the serialization info indicating the real type
+ // of object that should be recreated during deserialization.
+ //
+ // At this point the serialized state looks like this:
+ // Data:
+ // realSerializedData1
+ // ...
+ // realSerializedDataN
+ // safeSerializationData -> this is the serialization data member of the parent type
+ // _serializedState -> list of saved serialized states from subclasses responding to the safe
+ // serialization event
+ // RealTypeSerializationName -> type which is using safe serialization
+ // Type:
+ // SafeSerializationManager
+ //
+ // That is, the serialized data claims to be of type SafeSerializationManager, however contains only the
+ // data from the real object being serialized along with one bit of safe serialization metadata.
+ //
+ // At deserialization time, since the serialized data claims to be of type SafeSerializationManager, the
+ // root object being created is an instance of the SafeSerializationManager class. However, it detects
+ // that this isn't a real SafeSerializationManager (by looking for the real type field in the metadata),
+ // and simply saves away the SerializationInfo and the real type being deserialized.
+ //
+ // Since SafeSerializationManager implements IObjectReference, the next step of deserialization is the
+ // GetRealObject callback. This callback is the one responsible for getting the
+ // SafeSerializationManager out of the way and instead creating an instance of the actual type which was
+ // serialized.
+ //
+ // It does this by first creating an instance of the real type being deserialzed (saved away in the
+ // deserialzation constructor), but not running any of its constructors. Instead, it walks the
+ // inheritance hierarchy (moving toward the most derived type) looking for the last full trust type to
+ // implement the standard ISerializable constructor before any type does not implement the constructor.
+ // It is this last type's deserialization constructor which is then invoked, passing in the saved
+ // SerializationInfo. Once the constructors are run, we return this object as the real deserialized
+ // object.
+ //
+ // The reason that we do this walk is so that ISerializable types can protect themselves from malicious
+ // input during deserialization by making their deserialization constructors unavailable to partial
+ // trust code. By not requiring every type have a copy of this constructor, partial trust code can
+ // participate in safe serialization and not be required to have access to the parent's constructor.
+ //
+ // It should be noted however, that this heuristic means that if a full trust type does derive from
+ // a transparent or partial trust type using this safe serialization mechanism, that full trust type
+ // will not have its constructor called. Further, the protection of not invoking partial trust
+ // deserialization constructors only comes into play if SafeSerializationManager is in control of
+ // deserialization, which means there must be at least one (even empty) safe serialization event
+ // handler registered.
+ //
+ // Another interesting note is that at this point there are now two SafeSerializationManagers alive for
+ // this deserialization. The first object is the one which is controlling the deserialization and was
+ // created as the root object of the deserialization. The second one is the object which contains the
+ // serialized data chunks and is a data member of the real object being deserialized. For this reason,
+ // the data objects cannot be notified that the deserialization is complete during GetRealObject since
+ // the ISafeSerializationData objects are not members of the active SafeSerializationManager instance.
+ //
+ // The next step is the OnDeserialized callback, which comes to SafeSerializableObject since it was
+ // pretending to be the root object of the deserialization. It responds to this callback by calling
+ // any existing OnDeserialized callback on the real type that was deserialized.
+ //
+ // The real type needs to call its data member SafeSerializationData object's CompleteDeserialization
+ // method in response to the OnDeserialized call. This CompleteDeserialization call will then iterate
+ // through the ISafeSerializationData objects calling each of their CompleteDeserialization methods so
+ // that they can plug the nearly-complete object with their saved data.
+ //
+ // The reason for having a new ISafeSerializationData interface which is basically identical to
+ // IDeserializationCallback is that IDeserializationCallback will be called on the stored data chunks
+ // by the serialization code when they are deserialized, and that's not a desirable behavior.
+ // Essentially, we need to change the meaning of the object parameter to mean "parent object which
+ // participated in safe serialization", rather than "this object".
+ //
+ // Implementing safe serialization on an ISerialiable type is relatively straight forward. (For an
+ // example, see System.Exception):
+ //
+ // 1. Include a data member of type SafeSerializationManager:
+ //
+ // private SafeSerializationManager _safeSerializationManager;
+ //
+ // 2. Add a protected SerializeObjectState event, which passes through to the SafeSerializationManager:
+ //
+ // protected event EventHandler<SafeSerializationEventArgs> SerializeObjectState
+ // {
+ // add { _safeSerializationManager.SerializeObjectState += value; }
+ // remove { _safeSerializationManager.SerializeObjectState -= value; }
+ // }
+ //
+ // 3. Serialize the safe serialization object in GetObjectData, and call its CompleteSerialization method:
+ //
+ // {
+ // info.AddValue("_safeSerializationManager", _safeSerializationManager, typeof(SafeSerializationManager));
+ // _safeSerializationManager.CompleteSerialization(this, info, context);
+ // }
+ //
+ // 4. Add an OnDeserialized handler if one doesn't already exist, and call CompleteDeserialization in it:
+ //
+ // [OnDeserialized]
+ // private void OnDeserialized(StreamingContext context)
+ // {
+ // _safeSerializationManager.CompleteDeserialization(this);
+ // }
+ //
+ // On the client side, using safe serialization is also pretty easy. For example:
+ //
+ // [Serializable]
+ // public class TransparentException : Exception
+ // {
+ // [Serializable]
+ // private struct TransparentExceptionState : ISafeSerializationData
+ // {
+ // public string _extraData;
+ //
+ // void ISafeSerializationData.CompleteDeserialization(object obj)
+ // {
+ // TransparentException exception = obj as TransparentException;
+ // exception._state = this;
+ // }
+ // }
+ //
+ // [NonSerialized]
+ // private TransparentExceptionState _state = new TransparentExceptionState();
+ //
+ // public TransparentException()
+ // {
+ // SerializeObjectState += delegate(object exception, SafeSerializationEventArgs eventArgs)
+ // {
+ // eventArgs.AddSerializedState(_state);
+ // };
+ // }
+ //
+ // public string ExtraData
+ // {
+ // get { return _state._extraData; }
+ // set { _state._extraData = value; }
+ // }
+ // }
+ //
+
+ // Interface to be supported by objects which are stored in safe serialization stores
+ public interface ISafeSerializationData
+ {
+ // CompleteDeserialization is called when the object to which the extra serialized data was attached
+ // has completed its deserialization, and now needs to be populated with the extra data stored in
+ // this object.
+ void CompleteDeserialization(object deserialized);
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/ISerializable.cs b/src/mscorlib/shared/System/Runtime/Serialization/ISerializable.cs
new file mode 100644
index 0000000000..383b3f07af
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/ISerializable.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ public interface ISerializable
+ {
+ void GetObjectData(SerializationInfo info, StreamingContext context);
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/OnDeserializedAttribute.cs b/src/mscorlib/shared/System/Runtime/Serialization/OnDeserializedAttribute.cs
new file mode 100644
index 0000000000..408a55ccf9
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/OnDeserializedAttribute.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+ public sealed class OnDeserializedAttribute : Attribute
+ {
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/OnDeserializingAttribute.cs b/src/mscorlib/shared/System/Runtime/Serialization/OnDeserializingAttribute.cs
new file mode 100644
index 0000000000..162857e8d3
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/OnDeserializingAttribute.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+ public sealed class OnDeserializingAttribute : Attribute
+ {
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/OnSerializedAttribute.cs b/src/mscorlib/shared/System/Runtime/Serialization/OnSerializedAttribute.cs
new file mode 100644
index 0000000000..020dd0257c
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/OnSerializedAttribute.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+ public sealed class OnSerializedAttribute : Attribute
+ {
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/OnSerializingAttribute.cs b/src/mscorlib/shared/System/Runtime/Serialization/OnSerializingAttribute.cs
new file mode 100644
index 0000000000..8dc8af3f23
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/OnSerializingAttribute.cs
@@ -0,0 +1,11 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [AttributeUsage(AttributeTargets.Method, Inherited = false)]
+ public sealed class OnSerializingAttribute : Attribute
+ {
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/OptionalFieldAttribute.cs b/src/mscorlib/shared/System/Runtime/Serialization/OptionalFieldAttribute.cs
new file mode 100644
index 0000000000..84daa539be
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/OptionalFieldAttribute.cs
@@ -0,0 +1,25 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [AttributeUsage(AttributeTargets.Field, Inherited = false)]
+ public sealed class OptionalFieldAttribute : Attribute
+ {
+ private int _versionAdded = 1;
+
+ public int VersionAdded
+ {
+ get { return _versionAdded; }
+ set
+ {
+ if (value < 1)
+ {
+ throw new ArgumentException(SR.Serialization_OptionalFieldVersionValue);
+ }
+ _versionAdded = value;
+ }
+ }
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/SafeSerializationEventArgs.cs b/src/mscorlib/shared/System/Runtime/Serialization/SafeSerializationEventArgs.cs
new file mode 100644
index 0000000000..896b91fca0
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/SafeSerializationEventArgs.cs
@@ -0,0 +1,31 @@
+// 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.Collections.Generic;
+
+namespace System.Runtime.Serialization
+{
+ // SafeSerializationEventArgs are provided to the delegates which do safe serialization. Each delegate
+ // serializes its own state into an IDeserializationCallback instance which must, itself, be serializable.
+ // These indivdiual states are then added to the SafeSerializationEventArgs in order to be saved away when
+ // the original ISerializable type is serialized.
+ public sealed class SafeSerializationEventArgs : EventArgs
+ {
+ private readonly List<object> _serializedStates = new List<object>();
+
+ internal SafeSerializationEventArgs() { }
+
+ public void AddSerializedState(ISafeSerializationData serializedState)
+ {
+ if (serializedState == null)
+ throw new ArgumentNullException(nameof(serializedState));
+ if (!serializedState.GetType().IsSerializable)
+ throw new ArgumentException(SR.Format(SR.Serialization_NonSerType, serializedState.GetType(), serializedState.GetType().Assembly.FullName));
+
+ _serializedStates.Add(serializedState);
+ }
+
+ public StreamingContext StreamingContext { get; }
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/SerializationException.cs b/src/mscorlib/shared/System/Runtime/Serialization/SerializationException.cs
new file mode 100644
index 0000000000..a359daf4f9
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/SerializationException.cs
@@ -0,0 +1,39 @@
+// 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.Serialization;
+
+namespace System.Runtime.Serialization
+{
+ [Serializable]
+ public class SerializationException : SystemException
+ {
+ private static String s_nullMessage = SR.SerializationException;
+
+ // Creates a new SerializationException with its message
+ // string set to a default message.
+ public SerializationException()
+ : base(s_nullMessage)
+ {
+ HResult = __HResults.COR_E_SERIALIZATION;
+ }
+
+ public SerializationException(String message)
+ : base(message)
+ {
+ HResult = __HResults.COR_E_SERIALIZATION;
+ }
+
+ public SerializationException(String message, Exception innerException)
+ : base(message, innerException)
+ {
+ HResult = __HResults.COR_E_SERIALIZATION;
+ }
+
+ protected SerializationException(SerializationInfo info, StreamingContext context)
+ : base(info, context)
+ {
+ }
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/SerializationInfoEnumerator.cs b/src/mscorlib/shared/System/Runtime/Serialization/SerializationInfoEnumerator.cs
new file mode 100644
index 0000000000..6399510736
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/SerializationInfoEnumerator.cs
@@ -0,0 +1,127 @@
+// 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.Collections;
+using System.Diagnostics;
+
+namespace System.Runtime.Serialization
+{
+ public struct SerializationEntry
+ {
+ private string _name;
+ private object _value;
+ private Type _type;
+
+ internal SerializationEntry(string entryName, object entryValue, Type entryType)
+ {
+ _name = entryName;
+ _value = entryValue;
+ _type = entryType;
+ }
+
+ public object Value => _value;
+ public string Name => _name;
+ public Type ObjectType => _type;
+ }
+
+ public sealed class SerializationInfoEnumerator : IEnumerator
+ {
+ private readonly string[] _members;
+ private readonly object[] _data;
+ private readonly Type[] _types;
+ private readonly int _numItems;
+ private int _currItem;
+ private bool _current;
+
+ internal SerializationInfoEnumerator(string[] members, object[] info, Type[] types, int numItems)
+ {
+ Debug.Assert(members != null, "[SerializationInfoEnumerator.ctor]members!=null");
+ Debug.Assert(info != null, "[SerializationInfoEnumerator.ctor]info!=null");
+ Debug.Assert(types != null, "[SerializationInfoEnumerator.ctor]types!=null");
+ Debug.Assert(numItems >= 0, "[SerializationInfoEnumerator.ctor]numItems>=0");
+ Debug.Assert(members.Length >= numItems, "[SerializationInfoEnumerator.ctor]members.Length>=numItems");
+ Debug.Assert(info.Length >= numItems, "[SerializationInfoEnumerator.ctor]info.Length>=numItems");
+ Debug.Assert(types.Length >= numItems, "[SerializationInfoEnumerator.ctor]types.Length>=numItems");
+
+ _members = members;
+ _data = info;
+ _types = types;
+
+ //The MoveNext semantic is much easier if we enforce that [0..m_numItems] are valid entries
+ //in the enumerator, hence we subtract 1.
+ _numItems = numItems - 1;
+ _currItem = -1;
+ _current = false;
+ }
+
+ public bool MoveNext()
+ {
+ if (_currItem < _numItems)
+ {
+ _currItem++;
+ _current = true;
+ }
+ else
+ {
+ _current = false;
+ }
+
+ return _current;
+ }
+
+ object IEnumerator.Current => Current;
+
+ public SerializationEntry Current
+ {
+ get
+ {
+ if (_current == false)
+ {
+ throw new InvalidOperationException(SR.InvalidOperation_EnumOpCantHappen);
+ }
+ return new SerializationEntry(_members[_currItem], _data[_currItem], _types[_currItem]);
+ }
+ }
+
+ public void Reset()
+ {
+ _currItem = -1;
+ _current = false;
+ }
+
+ public string Name
+ {
+ get
+ {
+ if (_current == false)
+ {
+ throw new InvalidOperationException(SR.InvalidOperation_EnumOpCantHappen);
+ }
+ return _members[_currItem];
+ }
+ }
+ public object Value
+ {
+ get
+ {
+ if (_current == false)
+ {
+ throw new InvalidOperationException(SR.InvalidOperation_EnumOpCantHappen);
+ }
+ return _data[_currItem];
+ }
+ }
+ public Type ObjectType
+ {
+ get
+ {
+ if (_current == false)
+ {
+ throw new InvalidOperationException(SR.InvalidOperation_EnumOpCantHappen);
+ }
+ return _types[_currItem];
+ }
+ }
+ }
+}
diff --git a/src/mscorlib/shared/System/Runtime/Serialization/StreamingContext.cs b/src/mscorlib/shared/System/Runtime/Serialization/StreamingContext.cs
new file mode 100644
index 0000000000..1026a87d1e
--- /dev/null
+++ b/src/mscorlib/shared/System/Runtime/Serialization/StreamingContext.cs
@@ -0,0 +1,53 @@
+// 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.
+
+namespace System.Runtime.Serialization
+{
+ [Serializable]
+ public struct StreamingContext
+ {
+ private readonly object _additionalContext;
+ private readonly StreamingContextStates _state;
+
+ public StreamingContext(StreamingContextStates state) : this(state, null)
+ {
+ }
+
+ public StreamingContext(StreamingContextStates state, object additional)
+ {
+ _state = state;
+ _additionalContext = additional;
+ }
+
+ public override bool Equals(object obj)
+ {
+ if (!(obj is StreamingContext))
+ {
+ return false;
+ }
+ StreamingContext ctx = (StreamingContext)obj;
+ return ctx._additionalContext == _additionalContext && ctx._state == _state;
+ }
+
+ public override int GetHashCode() => (int)_state;
+
+ public StreamingContextStates State => _state;
+
+ public object Context => _additionalContext;
+ }
+
+ [Flags]
+ public enum StreamingContextStates
+ {
+ CrossProcess = 0x01,
+ CrossMachine = 0x02,
+ File = 0x04,
+ Persistence = 0x08,
+ Remoting = 0x10,
+ Other = 0x20,
+ Clone = 0x40,
+ CrossAppDomain = 0x80,
+ All = 0xFF,
+ }
+}