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// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
//
// <OWNER>GPaperin</OWNER>
// <OWNER>Microsoft</OWNER>
using System;
using System.Security;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
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 IMapView`2 interface on managed
// objects that implement IReadOnlyDictionary`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 IReadOnlyDictionaryToIMapViewAdapter objects. Rather, they are of type
// IReadOnlyDictionary<K, V>. No actual IReadOnlyDictionaryToIMapViewAdapter object is ever instantiated. Thus, you will
// see a lot of expressions that cast "this" to "IReadOnlyDictionary<K, V>".
[DebuggerDisplay("Size = {Size}")]
internal sealed class IReadOnlyDictionaryToIMapViewAdapter
{
private IReadOnlyDictionaryToIMapViewAdapter()
{
Contract.Assert(false, "This class is never instantiated");
}
// V Lookup(K key)
[SecurityCritical]
internal V Lookup<K, V>(K key)
{
IReadOnlyDictionary<K, V> _this = JitHelpers.UnsafeCast<IReadOnlyDictionary<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>()
{
IReadOnlyDictionary<K, V> _this = JitHelpers.UnsafeCast<IReadOnlyDictionary<K, V>>(this);
return (uint)_this.Count;
}
// bool HasKey(K key)
[SecurityCritical]
internal bool HasKey<K, V>(K key)
{
IReadOnlyDictionary<K, V> _this = JitHelpers.UnsafeCast<IReadOnlyDictionary<K, V>>(this);
return _this.ContainsKey(key);
}
// void Split(out IMapView<K, V> first, out IMapView<K, V> second)
[SecurityCritical]
internal void Split<K, V>(out IMapView<K, V> first, out IMapView<K, V> second)
{
IReadOnlyDictionary<K, V> _this = JitHelpers.UnsafeCast<IReadOnlyDictionary<K, V>>(this);
if (_this.Count < 2) {
first = null;
second = null;
return;
}
ConstantSplittableMap<K, V> splittableMap = _this as ConstantSplittableMap<K, V>;
if (splittableMap == null)
splittableMap = new ConstantSplittableMap<K, V>(_this);
splittableMap.Split(out first, out second);
}
}
}
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