aspnetcore/src/Microsoft.AspNet.Security.W.../NativeInterop/SafeCredentialReference.cs

87 lines
2.7 KiB
C#

// Copyright (c) Microsoft Open Technologies, Inc.
// All Rights Reserved
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR
// CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
// WITHOUT LIMITATION ANY IMPLIED WARRANTIES OR CONDITIONS OF
// TITLE, FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABLITY OR
// NON-INFRINGEMENT.
// See the Apache 2 License for the specific language governing
// permissions and limitations under the License.
// -----------------------------------------------------------------------
// <copyright file="SafeCredentialReference.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// -----------------------------------------------------------------------
using System;
using System.Runtime.CompilerServices;
using Microsoft.Win32.SafeHandles;
namespace Microsoft.AspNet.Security.Windows
{
internal sealed class SafeCredentialReference : CriticalHandleMinusOneIsInvalid
{
// Static cache will return the target handle if found the reference in the table.
internal SafeFreeCredentials _Target;
private SafeCredentialReference(SafeFreeCredentials target)
: base()
{
// Bumps up the refcount on Target to signify that target handle is statically cached so
// its dispose should be postponed
bool b = false;
RuntimeHelpers.PrepareConstrainedRegions();
try
{
target.DangerousAddRef(ref b);
}
catch
{
if (b)
{
target.DangerousRelease();
b = false;
}
}
finally
{
if (b)
{
_Target = target;
SetHandle(new IntPtr(0)); // make this handle valid
}
}
}
internal static SafeCredentialReference CreateReference(SafeFreeCredentials target)
{
SafeCredentialReference result = new SafeCredentialReference(target);
if (result.IsInvalid)
{
return null;
}
return result;
}
protected override bool ReleaseHandle()
{
SafeFreeCredentials target = _Target;
if (target != null)
{
target.DangerousRelease();
}
_Target = null;
return true;
}
}
}