#region Apache License
//
// Licensed to the Apache Software Foundation (ASF) under one or more 
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership. 
// The ASF licenses this file to you 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
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#endregion

using System;

namespace log4net.Core;

/// <summary>
/// A SecurityContext used by log4net when interacting with protected resources
/// </summary>
/// <remarks>
/// <para>
/// A SecurityContext used by log4net when interacting with protected resources
/// for example with operating system services. This can be used to impersonate
/// a principal that has been granted privileges on the system resources.
/// </para>
/// </remarks>
/// <author>Nicko Cadell</author>
public abstract class SecurityContext
{
  /// <summary>
  /// Impersonate this SecurityContext
  /// </summary>
  /// <param name="state">State supplied by the caller</param>
  /// <returns>An <see cref="IDisposable"/> instance that will
  /// revoke the impersonation of this SecurityContext, or <c>null</c></returns>
  /// <remarks>
  /// <para>
  /// Impersonate this security context. Further calls on the current
  /// thread should now be made in the security context provided
  /// by this object. When the <see cref="IDisposable"/> result 
  /// <see cref="IDisposable.Dispose"/> method is called the security
  /// context of the thread should be reverted to the state it was in
  /// before <see cref="Impersonate"/> was called.
  /// </para>
  /// </remarks>
  public abstract IDisposable? Impersonate(object state);
}
