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// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
//
// <OWNER>GPaperin</OWNER>
// <OWNER>Microsoft</OWNER>
using System;
using System.Security;
using System.Reflection;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Diagnostics.Contracts;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;
namespace System.Runtime.InteropServices.WindowsRuntime
{
// This is a set of stub methods implementing the support for the IMap`2 interface on managed
// objects that implement IDictionary`2. Used by the interop mashaling infrastructure.
//
// The methods on this class must be written VERY carefully to avoid introducing security holes.
// That's because they are invoked with special "this"! The "this" object
// for all of these methods are not DictionaryToMapAdapter objects. Rather, they are of type
// IDictionary<K, V>. No actual DictionaryToMapAdapter object is ever instantiated. Thus, you will
// see a lot of expressions that cast "this" to "IDictionary<K, V>".
internal sealed class DictionaryToMapAdapter
{
private DictionaryToMapAdapter()
{
Contract.Assert(false, "This class is never instantiated");
}
// V Lookup(K key)
[SecurityCritical]
internal V Lookup<K, V>(K key)
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
V value;
bool keyFound = _this.TryGetValue(key, out value);
if (!keyFound)
{
Exception e = new KeyNotFoundException(Environment.GetResourceString("Arg_KeyNotFound"));
e.SetErrorCode(__HResults.E_BOUNDS);
throw e;
}
return value;
}
// uint Size { get }
[SecurityCritical]
internal uint Size<K, V>()
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
return (uint)_this.Count;
}
// bool HasKey(K key)
[SecurityCritical]
internal bool HasKey<K, V>(K key)
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
return _this.ContainsKey(key);
}
// IMapView<K, V> GetView()
[SecurityCritical]
internal IReadOnlyDictionary<K, V> GetView<K, V>()
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
Contract.Assert(_this != null);
// Note: This dictionary is not really read-only - you could QI for a modifiable
// dictionary. We gain some perf by doing this. We believe this is acceptable.
IReadOnlyDictionary<K, V> roDictionary = _this as IReadOnlyDictionary<K, V>;
if (roDictionary == null)
{
roDictionary = new ReadOnlyDictionary<K, V>(_this);
}
return roDictionary;
}
// bool Insert(K key, V value)
[SecurityCritical]
internal bool Insert<K, V>(K key, V value)
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
bool replacing = _this.ContainsKey(key);
_this[key] = value;
return replacing;
}
// void Remove(K key)
[SecurityCritical]
internal void Remove<K, V>(K key)
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
bool removed = _this.Remove(key);
if (!removed)
{
Exception e = new KeyNotFoundException(Environment.GetResourceString("Arg_KeyNotFound"));
e.SetErrorCode(__HResults.E_BOUNDS);
throw e;
}
}
// void Clear()
[SecurityCritical]
internal void Clear<K, V>()
{
IDictionary<K, V> _this = JitHelpers.UnsafeCast<IDictionary<K, V>>(this);
_this.Clear();
}
}
}
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