SafeReversePInvokeHandle.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Core / CSharp / System / Windows / Media / SafeReversePInvokeHandle.cs / 1305600 / SafeReversePInvokeHandle.cs
                        

                        
                            //---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// 
// Description: 
//      A safe way to deal with unmanaged MIL interface pointers.
//--------------------------------------------------------------------------- 

using System;
using System.IO;
using System.Security; 
using System.Security.Permissions;
using System.Collections; 
using System.Reflection; 
using MS.Internal;
using MS.Win32; 
using System.Diagnostics;
using System.Windows.Media;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices; 
using Microsoft.Win32.SafeHandles;
using Microsoft.Internal; 
 
using UnsafeNativeMethods=MS.Win32.PresentationCore.UnsafeNativeMethods;
 
namespace System.Windows.Media
{
    internal class SafeReversePInvokeWrapper : SafeHandleZeroOrMinusOneIsInvalid
    { 
        /// 
        /// Use this constructor if the handle isn't ready yet and later 
        /// set the handle with SetHandle. SafeMILHandle owns the release 
        /// of the handle.
        ///  
        /// 
        ///    Critical: This derives from a class that has a link demand and inheritance demand
        ///    TreatAsSafe: Ok to call constructor
        ///   
        [SecurityCritical]
        internal SafeReversePInvokeWrapper() : base(true) 
        { 
        }
 
        /// 
        /// Use this constructor if the handle exists at construction time.
        /// SafeMILHandle owns the release of the parameter.
        ///  
        /// 
        /// Calls into native code to wrap a reverse p-invoke delegate into a CReversePInvokeDelegateWrapper. 
        ///  
        [SecurityCritical]
        internal SafeReversePInvokeWrapper(IntPtr delegatePtr) : base(true) 
        {
            // Wrap the reverse p-invoke into a reversePInvokeWrapper.
            IntPtr reversePInvokeWrapper;
            HRESULT.Check(UnsafeNativeMethods.MilCoreApi.MilCreateReversePInvokeWrapper(delegatePtr, out reversePInvokeWrapper)); 

            SetHandle(reversePInvokeWrapper); 
        } 

        ///  
        /// Critical - calls unmanaged code, not treat as safe because you must
        ///            validate that handle is a valid COM object.
        /// 
        [SecurityCritical] 
        protected override bool ReleaseHandle()
        { 
            if (handle != IntPtr.Zero) 
            {
                UnsafeNativeMethods.MilCoreApi.MilReleasePInvokePtrBlocking(handle); 
            }
            UnsafeNativeMethods.MILUnknown.ReleaseInterface(ref handle);

            return true; 
        }
    } 
} 


// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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