Code:
/ Net / Net / 3.5.50727.3053 / DEVDIV / depot / DevDiv / releases / Orcas / SP / wpf / src / Core / CSharp / System / Windows / Media / ChannelManager.cs / 1 / ChannelManager.cs
//------------------------------------------------------------------------------ // //// Copyright (C) Microsoft Corporation. All rights reserved. // // // Description: // The ChannelManager is a helper structure internal to MediaContext // that abstracts out channel creation, storage and destruction. // //----------------------------------------------------------------------------- using System; using System.Collections; using System.Collections.Generic; using System.ComponentModel; using System.Diagnostics; using System.Runtime.InteropServices; using System.Threading; using System.Windows.Threading; using System.Windows; using System.Windows.Interop; using System.Windows.Media; using System.Windows.Media.Animation; using System.Windows.Media.Composition; using System.Security; using MS.Internal; using MS.Utility; using MS.Win32; using Microsoft.Win32.SafeHandles; using SR=MS.Internal.PresentationCore.SR; using SRID=MS.Internal.PresentationCore.SRID; using UnsafeNativeMethods=MS.Win32.PresentationCore.UnsafeNativeMethods.MilCoreApi; namespace System.Windows.Media { partial class MediaContext { ////// A helper structure that abstracts channel management. /// ////// The common agreement (avcomptm, avpttrev) is that channel creation /// should be considered unsafe and therefore subject to control via /// the SecurityCritical/SecurityTreatAsSafe mechanism. /// /// On the other hand, using a channel that has been created by the /// MediaContext is considered safe. /// /// This class expresses the above policy by hiding channel creation /// and storage within the MediaContext while allowing to access /// the channels at will. /// private struct ChannelManager { ////// Opens an asynchronous channel. /// ////// Critical - Creates a channel, calls a Channel method, calls methods performing elevations. /// TreatAsSafe - It is safe for the media context to create and use a channel. /// [SecurityCritical, SecurityTreatAsSafe] internal void CreateChannels(bool hasLayeredWindows) { Invariant.Assert(_asyncChannel == null); Invariant.Assert(_asyncOutOfBandChannel == null); // Create a channel into the async composition device. // Pass in a reference to the global mediasystem channel so that it uses // the same partition. _asyncChannel = new DUCE.Channel( System.Windows.Media.MediaSystem.ServiceChannel, false, // not out of band false, // not a layered window specific channel System.Windows.Media.MediaSystem.Connection, IntPtr.Zero // [....] transport ); _asyncOutOfBandChannel = new DUCE.Channel( System.Windows.Media.MediaSystem.ServiceChannel, true, // out of band false, // not a layered window specific channel System.Windows.Media.MediaSystem.Connection, IntPtr.Zero // [....] transport ); } ////// Closes all opened channels. /// ////// Critical - Closes channels. /// TreatAsSafe - It is safe for the media context to [....] channels channel. /// [SecurityCritical, SecurityTreatAsSafe] internal void RemoveSyncChannels() { // // Close the synchronous channels. // if (_freeSyncChannels != null) { while (_freeSyncChannels.Count > 0) { _freeSyncChannels.Dequeue().Close(); } _freeSyncChannels = null; } if (_syncServiceChannel != null) { _syncServiceChannel.Close(); _syncServiceChannel = null; } } ////// Closes all opened channels. /// ////// Critical - Closes channels. /// TreatAsSafe - It is safe for the media context to close a channel. /// [SecurityCritical, SecurityTreatAsSafe] internal void RemoveChannels() { if (_asyncChannel != null) { _asyncChannel.Close(); _asyncChannel = null; } if (_asyncOutOfBandChannel != null) { _asyncOutOfBandChannel.Close(); _asyncOutOfBandChannel = null; } RemoveSyncChannels(); if (_pSyncConnection != IntPtr.Zero) { HRESULT.Check(UnsafeNativeMethods.MilTransport_DisconnectTransport( _pSyncConnection)); _pSyncConnection = IntPtr.Zero; } } ////// Create a fresh or fetch one from the pool synchronous channel. /// ////// Critical - Creates and returns a synchronous channel. /// TreatAsSafe - Using a channel created by the media context is safe. /// [SecurityCritical, SecurityTreatAsSafe] internal DUCE.Channel AllocateSyncChannel() { DUCE.Channel syncChannel; if (_pSyncConnection == IntPtr.Zero) { _pSyncConnection = System.Windows.Media.MediaSystem.ConnectSyncTransport( out _pSyncPacketTransport ); } if (_freeSyncChannels == null) { // // Ensure the free [....] channels queue... // _freeSyncChannels = new Queue(3); } if (_freeSyncChannels.Count > 0) { // // If there is a free [....] channel in the queue, we're done: // return _freeSyncChannels.Dequeue(); } else { // // Otherwise, create a new channel. We will try to cache it // when the ReleaseSyncChannel call is made. Also ensure the // synchronous service channel and glyph cache. // if (_syncServiceChannel == null) { _syncServiceChannel = new DUCE.Channel( null, false, // not out of band false, // not a layered window specific channel _pSyncConnection, _pSyncPacketTransport ); } syncChannel = new DUCE.Channel( _syncServiceChannel, false, // not out of band false, // not a layered window specific channel _pSyncConnection, _pSyncPacketTransport ); return syncChannel; } } /// /// Returns a [....] channel back to the pool. /// ////// Critical - Creates and returns a synchronous channel. /// TreatAsSafe - Closing a channel is safe. /// [SecurityCritical, SecurityTreatAsSafe] internal void ReleaseSyncChannel(DUCE.Channel channel) { Invariant.Assert(_freeSyncChannels != null); // // A decision needs to be made whether or not we're interested // in re-using this channel later. For now, store up to three // synchronous channel in the queue. // if (_freeSyncChannels.Count <= 3) { // // Since we don't close the channel, verify that // the RemoveAndReleaseQueue is empty for resources. // Debug.Assert(channel.IsRemoveAndReleaseQueueEmpty()); _freeSyncChannels.Enqueue(channel); } else { channel.Close(); } } ////// Flushes the remove and release queues of all channels /// ////// Critical - Performs commands on channels. /// TreatAsSafe - Flushing commands that have already been enqueued is safe. /// [SecurityCritical, SecurityTreatAsSafe] internal void FlushAllRemoveReleaseQueues() { FlushRemoveAndReleaseQueues(_asyncChannel); FlushRemoveAndReleaseQueues(_asyncOutOfBandChannel); } ////// Private helper function to flush the remove and release queues of a channel /// ////// Critical - Performs commands on channels. /// [SecurityCritical] private void FlushRemoveAndReleaseQueues(DUCE.Channel channel) { if (channel != null) { channel.ProcessRemoveCommand(); channel.ProcessReleaseCommand(); channel.ClearRemoveAndReleaseQueue(); } } ////// Returns the asynchronous channel. /// ////// Critical - Channels are a controlled unmanaged resource. /// TreatAsSafe - Using a channel created by the media context is safe. /// internal DUCE.Channel Channel { [SecurityCritical, SecurityTreatAsSafe] get { return _asyncChannel; } } ////// Returns the asynchronous out-of-band channel. /// ////// Critical - Channels are a controlled unmanaged resource. /// TreatAsSafe - Using a channel created by the media context is safe. /// internal DUCE.Channel OutOfBandChannel { [SecurityCritical, SecurityTreatAsSafe] get { return _asyncOutOfBandChannel; } } ////// The asynchronous channel. /// ////// This field will be replaced with an asynchronous channel table as per task #26681. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private DUCE.Channel _asyncChannel; ////// The asynchronous out-of-band channel. /// ////// This is needed by CompositionTarget for handling WM_PAINT, etc. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private DUCE.Channel _asyncOutOfBandChannel; ////// We store the free synchronous channels for later re-use in this queue. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private Queue_freeSyncChannels; /// /// The service channel to the synchronous partition. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private DUCE.Channel _syncServiceChannel; ////// Pointer to the unmanaged transport object. /// ////// Critical - Controlled unmanaged resource. /// [SecurityCritical] private IntPtr _pSyncPacketTransport; ////// Pointer to the unmanaged connection object. /// ////// Critical - Controlled unmanaged resource. /// [SecurityCritical] private IntPtr _pSyncConnection; } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved. //------------------------------------------------------------------------------ // //// Copyright (C) Microsoft Corporation. All rights reserved. // // // Description: // The ChannelManager is a helper structure internal to MediaContext // that abstracts out channel creation, storage and destruction. // //----------------------------------------------------------------------------- using System; using System.Collections; using System.Collections.Generic; using System.ComponentModel; using System.Diagnostics; using System.Runtime.InteropServices; using System.Threading; using System.Windows.Threading; using System.Windows; using System.Windows.Interop; using System.Windows.Media; using System.Windows.Media.Animation; using System.Windows.Media.Composition; using System.Security; using MS.Internal; using MS.Utility; using MS.Win32; using Microsoft.Win32.SafeHandles; using SR=MS.Internal.PresentationCore.SR; using SRID=MS.Internal.PresentationCore.SRID; using UnsafeNativeMethods=MS.Win32.PresentationCore.UnsafeNativeMethods.MilCoreApi; namespace System.Windows.Media { partial class MediaContext { ////// A helper structure that abstracts channel management. /// ////// The common agreement (avcomptm, avpttrev) is that channel creation /// should be considered unsafe and therefore subject to control via /// the SecurityCritical/SecurityTreatAsSafe mechanism. /// /// On the other hand, using a channel that has been created by the /// MediaContext is considered safe. /// /// This class expresses the above policy by hiding channel creation /// and storage within the MediaContext while allowing to access /// the channels at will. /// private struct ChannelManager { ////// Opens an asynchronous channel. /// ////// Critical - Creates a channel, calls a Channel method, calls methods performing elevations. /// TreatAsSafe - It is safe for the media context to create and use a channel. /// [SecurityCritical, SecurityTreatAsSafe] internal void CreateChannels(bool hasLayeredWindows) { Invariant.Assert(_asyncChannel == null); Invariant.Assert(_asyncOutOfBandChannel == null); // Create a channel into the async composition device. // Pass in a reference to the global mediasystem channel so that it uses // the same partition. _asyncChannel = new DUCE.Channel( System.Windows.Media.MediaSystem.ServiceChannel, false, // not out of band false, // not a layered window specific channel System.Windows.Media.MediaSystem.Connection, IntPtr.Zero // [....] transport ); _asyncOutOfBandChannel = new DUCE.Channel( System.Windows.Media.MediaSystem.ServiceChannel, true, // out of band false, // not a layered window specific channel System.Windows.Media.MediaSystem.Connection, IntPtr.Zero // [....] transport ); } ////// Closes all opened channels. /// ////// Critical - Closes channels. /// TreatAsSafe - It is safe for the media context to [....] channels channel. /// [SecurityCritical, SecurityTreatAsSafe] internal void RemoveSyncChannels() { // // Close the synchronous channels. // if (_freeSyncChannels != null) { while (_freeSyncChannels.Count > 0) { _freeSyncChannels.Dequeue().Close(); } _freeSyncChannels = null; } if (_syncServiceChannel != null) { _syncServiceChannel.Close(); _syncServiceChannel = null; } } ////// Closes all opened channels. /// ////// Critical - Closes channels. /// TreatAsSafe - It is safe for the media context to close a channel. /// [SecurityCritical, SecurityTreatAsSafe] internal void RemoveChannels() { if (_asyncChannel != null) { _asyncChannel.Close(); _asyncChannel = null; } if (_asyncOutOfBandChannel != null) { _asyncOutOfBandChannel.Close(); _asyncOutOfBandChannel = null; } RemoveSyncChannels(); if (_pSyncConnection != IntPtr.Zero) { HRESULT.Check(UnsafeNativeMethods.MilTransport_DisconnectTransport( _pSyncConnection)); _pSyncConnection = IntPtr.Zero; } } ////// Create a fresh or fetch one from the pool synchronous channel. /// ////// Critical - Creates and returns a synchronous channel. /// TreatAsSafe - Using a channel created by the media context is safe. /// [SecurityCritical, SecurityTreatAsSafe] internal DUCE.Channel AllocateSyncChannel() { DUCE.Channel syncChannel; if (_pSyncConnection == IntPtr.Zero) { _pSyncConnection = System.Windows.Media.MediaSystem.ConnectSyncTransport( out _pSyncPacketTransport ); } if (_freeSyncChannels == null) { // // Ensure the free [....] channels queue... // _freeSyncChannels = new Queue(3); } if (_freeSyncChannels.Count > 0) { // // If there is a free [....] channel in the queue, we're done: // return _freeSyncChannels.Dequeue(); } else { // // Otherwise, create a new channel. We will try to cache it // when the ReleaseSyncChannel call is made. Also ensure the // synchronous service channel and glyph cache. // if (_syncServiceChannel == null) { _syncServiceChannel = new DUCE.Channel( null, false, // not out of band false, // not a layered window specific channel _pSyncConnection, _pSyncPacketTransport ); } syncChannel = new DUCE.Channel( _syncServiceChannel, false, // not out of band false, // not a layered window specific channel _pSyncConnection, _pSyncPacketTransport ); return syncChannel; } } /// /// Returns a [....] channel back to the pool. /// ////// Critical - Creates and returns a synchronous channel. /// TreatAsSafe - Closing a channel is safe. /// [SecurityCritical, SecurityTreatAsSafe] internal void ReleaseSyncChannel(DUCE.Channel channel) { Invariant.Assert(_freeSyncChannels != null); // // A decision needs to be made whether or not we're interested // in re-using this channel later. For now, store up to three // synchronous channel in the queue. // if (_freeSyncChannels.Count <= 3) { // // Since we don't close the channel, verify that // the RemoveAndReleaseQueue is empty for resources. // Debug.Assert(channel.IsRemoveAndReleaseQueueEmpty()); _freeSyncChannels.Enqueue(channel); } else { channel.Close(); } } ////// Flushes the remove and release queues of all channels /// ////// Critical - Performs commands on channels. /// TreatAsSafe - Flushing commands that have already been enqueued is safe. /// [SecurityCritical, SecurityTreatAsSafe] internal void FlushAllRemoveReleaseQueues() { FlushRemoveAndReleaseQueues(_asyncChannel); FlushRemoveAndReleaseQueues(_asyncOutOfBandChannel); } ////// Private helper function to flush the remove and release queues of a channel /// ////// Critical - Performs commands on channels. /// [SecurityCritical] private void FlushRemoveAndReleaseQueues(DUCE.Channel channel) { if (channel != null) { channel.ProcessRemoveCommand(); channel.ProcessReleaseCommand(); channel.ClearRemoveAndReleaseQueue(); } } ////// Returns the asynchronous channel. /// ////// Critical - Channels are a controlled unmanaged resource. /// TreatAsSafe - Using a channel created by the media context is safe. /// internal DUCE.Channel Channel { [SecurityCritical, SecurityTreatAsSafe] get { return _asyncChannel; } } ////// Returns the asynchronous out-of-band channel. /// ////// Critical - Channels are a controlled unmanaged resource. /// TreatAsSafe - Using a channel created by the media context is safe. /// internal DUCE.Channel OutOfBandChannel { [SecurityCritical, SecurityTreatAsSafe] get { return _asyncOutOfBandChannel; } } ////// The asynchronous channel. /// ////// This field will be replaced with an asynchronous channel table as per task #26681. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private DUCE.Channel _asyncChannel; ////// The asynchronous out-of-band channel. /// ////// This is needed by CompositionTarget for handling WM_PAINT, etc. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private DUCE.Channel _asyncOutOfBandChannel; ////// We store the free synchronous channels for later re-use in this queue. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private Queue_freeSyncChannels; /// /// The service channel to the synchronous partition. /// ////// Critical - Channels are a controlled unmanaged resource. /// [SecurityCritical] private DUCE.Channel _syncServiceChannel; ////// Pointer to the unmanaged transport object. /// ////// Critical - Controlled unmanaged resource. /// [SecurityCritical] private IntPtr _pSyncPacketTransport; ////// Pointer to the unmanaged connection object. /// ////// Critical - Controlled unmanaged resource. /// [SecurityCritical] private IntPtr _pSyncConnection; } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu

This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- WindowsSlider.cs
- CloseSequenceResponse.cs
- TypeUsageBuilder.cs
- TextBox.cs
- Configuration.cs
- HtmlTableRowCollection.cs
- DesignerInterfaces.cs
- ContourSegment.cs
- Vector3DCollection.cs
- StatusBarPanel.cs
- MissingMemberException.cs
- HttpRequestCacheValidator.cs
- TheQuery.cs
- HtmlInputCheckBox.cs
- EntityObject.cs
- DesignerActionPropertyItem.cs
- ObjectNavigationPropertyMapping.cs
- ImageIndexConverter.cs
- XmlQualifiedNameTest.cs
- XhtmlBasicValidationSummaryAdapter.cs
- UnicodeEncoding.cs
- webclient.cs
- ClientTargetSection.cs
- RelatedCurrencyManager.cs
- SiteIdentityPermission.cs
- SmtpFailedRecipientsException.cs
- CqlWriter.cs
- NullReferenceException.cs
- ZipIOModeEnforcingStream.cs
- XmlEntityReference.cs
- RtType.cs
- AstTree.cs
- XamlStackWriter.cs
- SwitchAttribute.cs
- StrongNameMembershipCondition.cs
- XsltException.cs
- MemberAccessException.cs
- RuntimeConfig.cs
- HttpHandlerActionCollection.cs
- ExtensionDataReader.cs
- FixedDocumentPaginator.cs
- FieldBuilder.cs
- TreeView.cs
- ISAPIWorkerRequest.cs
- InfiniteTimeSpanConverter.cs
- LinqDataSourceView.cs
- PngBitmapEncoder.cs
- PolicyLevel.cs
- TextServicesCompartment.cs
- Speller.cs
- ListViewHitTestInfo.cs
- FontCollection.cs
- SiteMapPath.cs
- PreviewKeyDownEventArgs.cs
- ReferentialConstraint.cs
- XmlDataDocument.cs
- UserInitiatedNavigationPermission.cs
- CursorInteropHelper.cs
- DataServiceRequest.cs
- CodeDOMUtility.cs
- RadialGradientBrush.cs
- StateItem.cs
- MessageDecoder.cs
- ZeroOpNode.cs
- ReachDocumentPageSerializer.cs
- QueuePathDialog.cs
- ArrayConverter.cs
- Vector3DAnimationUsingKeyFrames.cs
- TextOnlyOutput.cs
- SymmetricKeyWrap.cs
- OperationGenerator.cs
- Camera.cs
- DataBoundControl.cs
- AnnotationHighlightLayer.cs
- WebPartAuthorizationEventArgs.cs
- Error.cs
- CultureSpecificStringDictionary.cs
- CopyOnWriteList.cs
- StatusBar.cs
- FileAuthorizationModule.cs
- ParseChildrenAsPropertiesAttribute.cs
- MarkupCompiler.cs
- CultureInfoConverter.cs
- RouteValueDictionary.cs
- WebPartTransformerAttribute.cs
- TagPrefixAttribute.cs
- SuppressMergeCheckAttribute.cs
- XmlSchemaAnnotated.cs
- RepeaterCommandEventArgs.cs
- TCPClient.cs
- LongValidator.cs
- HtmlImageAdapter.cs
- AssemblySettingAttributes.cs
- DesignerGenericWebPart.cs
- TraceContextRecord.cs
- FixedLineResult.cs
- EditorPart.cs
- RenameRuleObjectDialog.Designer.cs
- SessionIDManager.cs
- InvariantComparer.cs