UnknownBitmapDecoder.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 / Imaging / UnknownBitmapDecoder.cs / 1305600 / UnknownBitmapDecoder.cs
                        

                        
                            //------------------------------------------------------------------------------ 
//  Microsoft Avalon
//  Copyright (c) Microsoft Corporation, All Rights Reserved
//
//  File: UnknownBitmapDecoder.cs 
//
//----------------------------------------------------------------------------- 
 
using System;
using System.IO; 
using System.Collections;
using System.Security;
using System.Security.Permissions;
using System.ComponentModel; 
using System.ComponentModel.Design.Serialization;
using System.Reflection; 
using Microsoft.Win32.SafeHandles; 
using MS.Internal;
using System.Diagnostics; 
using System.Windows.Media;
using System.Globalization;
using System.Runtime.InteropServices;
 
namespace System.Windows.Media.Imaging
{ 
    #region UnknownBitmapDecoder 

    ///  
    /// The built-in Microsoft Unknown (Bitmap) Decoder.
    /// 
    internal sealed class UnknownBitmapDecoder : BitmapDecoder
    { 
        /// 
        /// This class is to allow us to call CoInitialize when the UnknownBitmapDecoder 
        /// is created, so that the unmanaged dll does not get unload until we are. 
        /// 
        private class CoInitSafeHandle : SafeMILHandle 
        {
            /// 
            /// Critical  - accesses critical code.
            /// TreatAsSafe - No inputs, does not touch any critical data with external input. 
            /// 
            [SecurityCritical, SecurityTreatAsSafe] 
            public CoInitSafeHandle() 
            {
                MS.Win32.PresentationCore.UnsafeNativeMethods.WICCodec.CoInitialize(IntPtr.Zero); 
            }

            /// 
            /// Critical  - accesses critical code. 
            /// TreatAsSafe - No inputs, does not touch any critical data with external input.
            ///  
            [SecurityCritical, SecurityTreatAsSafe] 
            protected override bool ReleaseHandle()
            { 
                MS.Win32.PresentationCore.UnsafeNativeMethods.WICCodec.CoUninitialize();

                return true;
            } 
        }
 
        ///  
        /// Don't allow construction of a decoder with no params
        ///  
        private UnknownBitmapDecoder()
        {
        }
 
        /// 
        /// Internal Constructor 
        ///  
        /// 
        /// Critical: Uses a SafeFileHandle, which is a SecurityCritical type (in v4). 
        ///     Calls SecurityCritical base class constructor.
        /// 
        [SecurityCritical]
        internal UnknownBitmapDecoder( 
            SafeMILHandle decoderHandle,
            BitmapDecoder decoder, 
            Uri baseUri, 
            Uri uri,
            Stream stream, 
            BitmapCreateOptions createOptions,
            BitmapCacheOption cacheOption,
            bool insertInDecoderCache,
            bool originalWritable, 
            Stream uriStream,
            UnmanagedMemoryStream unmanagedMemoryStream, 
            SafeFileHandle safeFilehandle 
            ) : base(decoderHandle, decoder, baseUri, uri, stream, createOptions, cacheOption, insertInDecoderCache, originalWritable, uriStream, unmanagedMemoryStream, safeFilehandle)
        { 
        }

        #region Internal Abstract
 
        /// Need to implement this to derive from the "sealed" object
        internal override void SealObject() 
        { 
            throw new NotImplementedException();
        } 

        #endregion

        ///  
        /// Store a safe handle to take care of calling CoInitialize
        /// and CoUninitialize for us when the object is created/disposed. 
        ///  
        private CoInitSafeHandle _safeHandle = new CoInitSafeHandle();
 
    }

    #endregion
} 


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

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