79 lines
2.7 KiB
C#
79 lines
2.7 KiB
C#
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//------------------------------------------------------------------------------
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// <copyright file="WrappedIUnknown.cs" company="Microsoft">
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// Copyright (c) Microsoft Corporation. All rights reserved.
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// </copyright>
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// <owner current="true" primary="true">[....]</owner>
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// <owner current="true" primary="false">[....]</owner>
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//------------------------------------------------------------------------------
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namespace System.Data.ProviderBase {
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using System;
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using System.Data.Common;
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using System.Runtime.CompilerServices;
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using System.Runtime.ConstrainedExecution;
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using System.Runtime.InteropServices;
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using System.Security;
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using System.Security.Permissions;
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using System.Threading;
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// We wrap the interface as a native IUnknown IntPtr so that every
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// thread that creates a connection will fake the correct context when
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// in transactions, otherwise everything is marshalled. We do this
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// for two reasons: first for the connection pooler, this is a significant
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// performance gain, second for the OLE DB provider, it doesn't marshal.
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internal class WrappedIUnknown : SafeHandle {
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internal WrappedIUnknown() : base(IntPtr.Zero, true) {
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}
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internal WrappedIUnknown(object unknown) : this() {
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if (null != unknown) {
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RuntimeHelpers.PrepareConstrainedRegions();
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try {} finally {
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#if !FULL_AOT_RUNTIME
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base.handle = Marshal.GetIUnknownForObject(unknown); //
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#endif
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}
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}
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}
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public override bool IsInvalid {
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get {
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return (IntPtr.Zero == base.handle);
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}
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}
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internal object ComWrapper() {
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// NOTE: Method, instead of property, to avoid being evaluated at
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// runtime in the debugger.
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object value = null;
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bool mustRelease = false;
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RuntimeHelpers.PrepareConstrainedRegions();
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try {
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DangerousAddRef(ref mustRelease);
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IntPtr handle = DangerousGetHandle();
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value = System.Runtime.Remoting.Services.EnterpriseServicesHelper.WrapIUnknownWithComObject(handle);
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}
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finally {
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if (mustRelease) {
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DangerousRelease();
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}
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}
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return value;
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}
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override protected bool ReleaseHandle() {
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// NOTE: The SafeHandle class guarantees this will be called exactly once.
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IntPtr ptr = base.handle;
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base.handle = IntPtr.Zero;
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if (IntPtr.Zero != ptr) {
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Marshal.Release(ptr);
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}
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return true;
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}
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}
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}
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