//------------------------------------------------------------------------------ // // Copyright (c) Microsoft Corporation. All rights reserved. // //------------------------------------------------------------------------------ using Microsoft.Win32.SafeHandles; using System; namespace Experimental.System.Messaging.Interop { internal class MessageQueueHandle : SafeHandleZeroOrMinusOneIsInvalid { public static readonly MessageQueueHandle InvalidHandle = new InvalidMessageQueueHandle(); MessageQueueHandle() : base(true) { } protected override bool ReleaseHandle() { SafeNativeMethods.MQCloseQueue(this.handle); return true; } public override bool IsInvalid { get { return base.IsInvalid || IsClosed; } } // A subclass needed to express InvalidHandle. The reason is that CLR notices that // ReleaseHandle requires a call to MQRT.DLL, and throws in the ctor if MQRT.DLL is not available, // even though CTOR ITSELF DOES NOT REQUIRE MQRT.DLL. // We address this by defining a NOOP ReleaseHandle sealed class InvalidMessageQueueHandle : MessageQueueHandle { protected override bool ReleaseHandle() { return true; } } } internal class CursorHandle : SafeHandleZeroOrMinusOneIsInvalid { public static readonly CursorHandle NullHandle = new InvalidCursorHandle(); protected CursorHandle() : base(true) { } protected override bool ReleaseHandle() { SafeNativeMethods.MQCloseCursor(this.handle); return true; } public override bool IsInvalid { get { return base.IsInvalid || IsClosed; } } // A subclass needed to express InvalidHandle. The reason is that CLR notices that // ReleaseHandle requires a call to MQRT.DLL, and throws in the ctor if MQRT.DLL is not available, // even though CTOR ITSELF DOES NOT REQUIRE MQRT.DLL. // We address this by defining a NOOP ReleaseHandle sealed class InvalidCursorHandle : CursorHandle { protected override bool ReleaseHandle() { return true; } } } internal class LocatorHandle : SafeHandleZeroOrMinusOneIsInvalid { public static readonly LocatorHandle InvalidHandle = new InvalidLocatorHandle(); protected LocatorHandle() : base(true) { } protected override bool ReleaseHandle() { SafeNativeMethods.MQLocateEnd(this.handle); return true; } public override bool IsInvalid { get { return base.IsInvalid || IsClosed; } } // A subclass needed to express InvalidHandle. The reason is that CLR notices that // ReleaseHandle requires a call to MQRT.DLL, and throws in the ctor if MQRT.DLL is not available, // even though CTOR ITSELF DOES NOT REQUIRE MQRT.DLL. // We address this by defining a NOOP ReleaseHandle sealed class InvalidLocatorHandle : LocatorHandle { protected override bool ReleaseHandle() { return true; } } } internal sealed class SecurityContextHandle : SafeHandleZeroOrMinusOneIsInvalid { internal SecurityContextHandle(IntPtr existingHandle) : base(true) { SetHandle(existingHandle); } protected override bool ReleaseHandle() { SafeNativeMethods.MQFreeSecurityContext(this.handle); return true; } public override bool IsInvalid { get { return base.IsInvalid || IsClosed; } } } }