Code:
/ Dotnetfx_Vista_SP2 / Dotnetfx_Vista_SP2 / 8.0.50727.4016 / DEVDIV / depot / DevDiv / releases / Orcas / QFE / 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
- Rotation3DKeyFrameCollection.cs
- StructuralObject.cs
- Compiler.cs
- SubclassTypeValidator.cs
- AttachedPropertyBrowsableForChildrenAttribute.cs
- MetadataArtifactLoaderCompositeFile.cs
- XmlAnyAttributeAttribute.cs
- CopyAttributesAction.cs
- SqlExpander.cs
- DBPropSet.cs
- ObjectDataSourceDisposingEventArgs.cs
- _HeaderInfoTable.cs
- HttpCapabilitiesSectionHandler.cs
- ConstraintConverter.cs
- FormViewInsertEventArgs.cs
- BooleanToVisibilityConverter.cs
- EntityClientCacheEntry.cs
- HMAC.cs
- CmsInterop.cs
- WindowsFormsHost.cs
- ReadOnlyDataSourceView.cs
- ProxyBuilder.cs
- SingleKeyFrameCollection.cs
- TextProperties.cs
- SystemUnicastIPAddressInformation.cs
- LogPolicy.cs
- DataServiceStreamResponse.cs
- BooleanProjectedSlot.cs
- DefaultMemberAttribute.cs
- ListViewUpdatedEventArgs.cs
- ProfilePropertySettings.cs
- RotationValidation.cs
- SqlDataReader.cs
- XmlUtil.cs
- ReferenceSchema.cs
- ParserHooks.cs
- VBCodeProvider.cs
- JsonFormatReaderGenerator.cs
- WebPartConnectionsEventArgs.cs
- DaylightTime.cs
- MessageQueuePermissionEntryCollection.cs
- ListViewInsertEventArgs.cs
- ObfuscationAttribute.cs
- MessagingDescriptionAttribute.cs
- XmlDataImplementation.cs
- AppSecurityManager.cs
- LostFocusEventManager.cs
- Block.cs
- ContentPlaceHolder.cs
- Activity.cs
- TraceHandlerErrorFormatter.cs
- SetterBase.cs
- ModelItemDictionary.cs
- SessionEndingCancelEventArgs.cs
- TrackingServices.cs
- Listbox.cs
- SchemaNames.cs
- RegisteredArrayDeclaration.cs
- ParsedAttributeCollection.cs
- FieldMetadata.cs
- GridViewRowCollection.cs
- SafeNativeMethods.cs
- _DynamicWinsockMethods.cs
- ProxyWebPart.cs
- DataGridViewCellStyle.cs
- AggregateNode.cs
- CompositeTypefaceMetrics.cs
- MessageQueuePermissionAttribute.cs
- DataBoundControlAdapter.cs
- TickBar.cs
- SatelliteContractVersionAttribute.cs
- SqlDataRecord.cs
- GridView.cs
- TransformedBitmap.cs
- DBCSCodePageEncoding.cs
- xsdvalidator.cs
- CounterSetInstanceCounterDataSet.cs
- VisualTreeHelper.cs
- AssociationSetEnd.cs
- SBCSCodePageEncoding.cs
- FixedBufferAttribute.cs
- XPathChildIterator.cs
- SafeMILHandle.cs
- InheritanceRules.cs
- StreamReader.cs
- LocatorManager.cs
- TrackingMemoryStream.cs
- WebHostUnsafeNativeMethods.cs
- ValidatorCompatibilityHelper.cs
- OperatingSystem.cs
- ImportedNamespaceContextItem.cs
- AssemblyAssociatedContentFileAttribute.cs
- CustomAttributeFormatException.cs
- ConnectionsZone.cs
- CommonObjectSecurity.cs
- ServiceReference.cs
- GridItemCollection.cs
- AstTree.cs
- CodeTypeReference.cs
- RandomNumberGenerator.cs