Code:
/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / clr / src / BCL / System / _LocalDataStore.cs / 1305376 / _LocalDataStore.cs
// ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== /*============================================================================== ** ** Class: LocalDataStore ** ** ** Purpose: Class that stores local data. This class is used in cooperation ** with the _LocalDataStoreMgr class. ** ** =============================================================================*/ namespace System { using System; using System.Threading; using System.Runtime.CompilerServices; using System.Diagnostics.Contracts; // Helper class to aid removal of LocalDataStore from the LocalDataStoreMgr // LocalDataStoreMgr does not holds references to LocalDataStoreHolder. It holds // references to LocalDataStore only. LocalDataStoreHolder finalizer will run once // the only outstanding reference to the store is in LocalDataStoreMgr. sealed internal class LocalDataStoreHolder { private LocalDataStore m_Store; public LocalDataStoreHolder(LocalDataStore store) { m_Store = store; } ~LocalDataStoreHolder() { LocalDataStore store = m_Store; if (store == null) return; store.Dispose(); } public LocalDataStore Store { get { return m_Store; } } } sealed internal class LocalDataStoreElement { private Object m_value; private long m_cookie; // This is immutable cookie of the slot used to verify that // the value is indeed indeed owned by the slot. Necessary // to avoid resurection holes. public LocalDataStoreElement(long cookie) { m_cookie = cookie; } public Object Value { get { return m_value; } set { m_value = value; } } public long Cookie { get { return m_cookie; } } } // This class will not be marked serializable sealed internal class LocalDataStore { private LocalDataStoreElement[] m_DataTable; private LocalDataStoreMgr m_Manager; /*========================================================================= ** Initialize the data store. =========================================================================*/ public LocalDataStore(LocalDataStoreMgr mgr, int InitialCapacity) { // Store the manager of the local data store. m_Manager = mgr; // Allocate the array that will contain the data. m_DataTable = new LocalDataStoreElement[InitialCapacity]; } /*========================================================================= ** Delete this store from its manager =========================================================================*/ internal void Dispose() { m_Manager.DeleteLocalDataStore(this); } /*========================================================================= ** Retrieves the value from the specified slot. =========================================================================*/ public Object GetData(LocalDataStoreSlot slot) { // Validate the slot. m_Manager.ValidateSlot(slot); // Cache the slot index to avoid synchronization issues. int slotIdx = slot.Slot; if (slotIdx >= 0) { // Delay expansion of m_DataTable if we can if (slotIdx >= m_DataTable.Length) return null; // Retrieve the data from the given slot. LocalDataStoreElement element = m_DataTable[slotIdx]; //Initially we prepopulate the elements to be null. if (element == null) return null; // Check that the element is owned by this slot by comparing cookies. // This is necesary to avoid resurection ----s. if (element.Cookie == slot.Cookie) return element.Value; // Fall thru and throw exception } throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_SlotHasBeenFreed")); } /*========================================================================== ** Sets the data in the specified slot. =========================================================================*/ public void SetData(LocalDataStoreSlot slot, Object data) { // Validate the slot. m_Manager.ValidateSlot(slot); // Cache the slot index to avoid synchronization issues. int slotIdx = slot.Slot; if (slotIdx >= 0) { LocalDataStoreElement element = (slotIdx < m_DataTable.Length) ? m_DataTable[slotIdx] : null; if (element == null) { element = PopulateElement(slot); } // Check that the element is owned by this slot by comparing cookies. // This is necesary to avoid resurection ----s. if (element.Cookie == slot.Cookie) { // Set the data on the given slot. element.Value = data; return; } // Fall thru and throw exception } throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_SlotHasBeenFreed")); } /*========================================================================= ** This method does clears the unused slot. * Assumes lock on m_Manager is taken =========================================================================*/ internal void FreeData(int slot, long cookie) { // We try to delay allocate the dataTable (in cases like the manager clearing a // just-freed slot in all stores if (slot >= m_DataTable.Length) return; LocalDataStoreElement element = m_DataTable[slot]; if (element != null && element.Cookie == cookie) m_DataTable[slot] = null; } /*========================================================================== ** Method used to expand the capacity of the local data store. =========================================================================*/ [System.Security.SecuritySafeCritical] // auto-generated private LocalDataStoreElement PopulateElement(LocalDataStoreSlot slot) { bool tookLock = false; RuntimeHelpers.PrepareConstrainedRegions(); try { Monitor.Enter(m_Manager, ref tookLock); // Make sure that the slot was not freed in the meantime int slotIdx = slot.Slot; if (slotIdx < 0) throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_SlotHasBeenFreed")); if (slotIdx >= m_DataTable.Length) { int capacity = m_Manager.GetSlotTableLength(); // Validate that the specified capacity is larger than the current one. Contract.Assert(capacity >= m_DataTable.Length, "LocalDataStore corrupted: capacity >= m_DataTable.Length"); // Allocate the new data table. LocalDataStoreElement[] NewDataTable = new LocalDataStoreElement[capacity]; // Copy all the objects into the new table. Array.Copy(m_DataTable, NewDataTable, m_DataTable.Length); // Save the new table. m_DataTable = NewDataTable; } // Validate that there is enough space in the local data store now Contract.Assert(slotIdx < m_DataTable.Length, "LocalDataStore corrupted: slotIdx < m_DataTable.Length"); if (m_DataTable[slotIdx] == null) m_DataTable[slotIdx] = new LocalDataStoreElement(slot.Cookie); return m_DataTable[slotIdx]; } finally { if (tookLock) Monitor.Exit(m_Manager); } } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== /*============================================================================== ** ** Class: LocalDataStore ** ** ** Purpose: Class that stores local data. This class is used in cooperation ** with the _LocalDataStoreMgr class. ** ** =============================================================================*/ namespace System { using System; using System.Threading; using System.Runtime.CompilerServices; using System.Diagnostics.Contracts; // Helper class to aid removal of LocalDataStore from the LocalDataStoreMgr // LocalDataStoreMgr does not holds references to LocalDataStoreHolder. It holds // references to LocalDataStore only. LocalDataStoreHolder finalizer will run once // the only outstanding reference to the store is in LocalDataStoreMgr. sealed internal class LocalDataStoreHolder { private LocalDataStore m_Store; public LocalDataStoreHolder(LocalDataStore store) { m_Store = store; } ~LocalDataStoreHolder() { LocalDataStore store = m_Store; if (store == null) return; store.Dispose(); } public LocalDataStore Store { get { return m_Store; } } } sealed internal class LocalDataStoreElement { private Object m_value; private long m_cookie; // This is immutable cookie of the slot used to verify that // the value is indeed indeed owned by the slot. Necessary // to avoid resurection holes. public LocalDataStoreElement(long cookie) { m_cookie = cookie; } public Object Value { get { return m_value; } set { m_value = value; } } public long Cookie { get { return m_cookie; } } } // This class will not be marked serializable sealed internal class LocalDataStore { private LocalDataStoreElement[] m_DataTable; private LocalDataStoreMgr m_Manager; /*========================================================================= ** Initialize the data store. =========================================================================*/ public LocalDataStore(LocalDataStoreMgr mgr, int InitialCapacity) { // Store the manager of the local data store. m_Manager = mgr; // Allocate the array that will contain the data. m_DataTable = new LocalDataStoreElement[InitialCapacity]; } /*========================================================================= ** Delete this store from its manager =========================================================================*/ internal void Dispose() { m_Manager.DeleteLocalDataStore(this); } /*========================================================================= ** Retrieves the value from the specified slot. =========================================================================*/ public Object GetData(LocalDataStoreSlot slot) { // Validate the slot. m_Manager.ValidateSlot(slot); // Cache the slot index to avoid synchronization issues. int slotIdx = slot.Slot; if (slotIdx >= 0) { // Delay expansion of m_DataTable if we can if (slotIdx >= m_DataTable.Length) return null; // Retrieve the data from the given slot. LocalDataStoreElement element = m_DataTable[slotIdx]; //Initially we prepopulate the elements to be null. if (element == null) return null; // Check that the element is owned by this slot by comparing cookies. // This is necesary to avoid resurection ----s. if (element.Cookie == slot.Cookie) return element.Value; // Fall thru and throw exception } throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_SlotHasBeenFreed")); } /*========================================================================== ** Sets the data in the specified slot. =========================================================================*/ public void SetData(LocalDataStoreSlot slot, Object data) { // Validate the slot. m_Manager.ValidateSlot(slot); // Cache the slot index to avoid synchronization issues. int slotIdx = slot.Slot; if (slotIdx >= 0) { LocalDataStoreElement element = (slotIdx < m_DataTable.Length) ? m_DataTable[slotIdx] : null; if (element == null) { element = PopulateElement(slot); } // Check that the element is owned by this slot by comparing cookies. // This is necesary to avoid resurection ----s. if (element.Cookie == slot.Cookie) { // Set the data on the given slot. element.Value = data; return; } // Fall thru and throw exception } throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_SlotHasBeenFreed")); } /*========================================================================= ** This method does clears the unused slot. * Assumes lock on m_Manager is taken =========================================================================*/ internal void FreeData(int slot, long cookie) { // We try to delay allocate the dataTable (in cases like the manager clearing a // just-freed slot in all stores if (slot >= m_DataTable.Length) return; LocalDataStoreElement element = m_DataTable[slot]; if (element != null && element.Cookie == cookie) m_DataTable[slot] = null; } /*========================================================================== ** Method used to expand the capacity of the local data store. =========================================================================*/ [System.Security.SecuritySafeCritical] // auto-generated private LocalDataStoreElement PopulateElement(LocalDataStoreSlot slot) { bool tookLock = false; RuntimeHelpers.PrepareConstrainedRegions(); try { Monitor.Enter(m_Manager, ref tookLock); // Make sure that the slot was not freed in the meantime int slotIdx = slot.Slot; if (slotIdx < 0) throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_SlotHasBeenFreed")); if (slotIdx >= m_DataTable.Length) { int capacity = m_Manager.GetSlotTableLength(); // Validate that the specified capacity is larger than the current one. Contract.Assert(capacity >= m_DataTable.Length, "LocalDataStore corrupted: capacity >= m_DataTable.Length"); // Allocate the new data table. LocalDataStoreElement[] NewDataTable = new LocalDataStoreElement[capacity]; // Copy all the objects into the new table. Array.Copy(m_DataTable, NewDataTable, m_DataTable.Length); // Save the new table. m_DataTable = NewDataTable; } // Validate that there is enough space in the local data store now Contract.Assert(slotIdx < m_DataTable.Length, "LocalDataStore corrupted: slotIdx < m_DataTable.Length"); if (m_DataTable[slotIdx] == null) m_DataTable[slotIdx] = new LocalDataStoreElement(slot.Cookie); return m_DataTable[slotIdx]; } finally { if (tookLock) Monitor.Exit(m_Manager); } } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007.
Link Menu
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- TypeGeneratedEventArgs.cs
- GacUtil.cs
- EncoderExceptionFallback.cs
- ListViewDataItem.cs
- OpacityConverter.cs
- DataDesignUtil.cs
- Constraint.cs
- RayMeshGeometry3DHitTestResult.cs
- AncestorChangedEventArgs.cs
- TreeView.cs
- AdjustableArrowCap.cs
- XmlSchemaIdentityConstraint.cs
- Focus.cs
- BuildDependencySet.cs
- SqlPersistenceProviderFactory.cs
- ImmutableClientRuntime.cs
- SourceInterpreter.cs
- AnimationStorage.cs
- SQLGuid.cs
- BinaryKeyIdentifierClause.cs
- SqlInternalConnectionTds.cs
- COM2FontConverter.cs
- CustomTrackingQuery.cs
- CommunicationObjectAbortedException.cs
- ListSourceHelper.cs
- TransformDescriptor.cs
- DeferredTextReference.cs
- PrinterSettings.cs
- PasswordPropertyTextAttribute.cs
- BindingMAnagerBase.cs
- Module.cs
- DataControlField.cs
- TextServicesContext.cs
- MemberPathMap.cs
- DataFieldCollectionEditor.cs
- BaseCAMarshaler.cs
- Table.cs
- RedBlackList.cs
- SkewTransform.cs
- VisualStyleRenderer.cs
- DependencyPropertyHelper.cs
- SimpleApplicationHost.cs
- _HeaderInfoTable.cs
- WsatProxy.cs
- Accessors.cs
- WebScriptMetadataMessageEncodingBindingElement.cs
- InfoCardRSAPKCS1SignatureDeformatter.cs
- OptimizedTemplateContent.cs
- TextControl.cs
- TextBounds.cs
- XmlSerializer.cs
- MenuItemBinding.cs
- RangeValidator.cs
- UndirectedGraph.cs
- ObjectAnimationBase.cs
- SqlDataSourceFilteringEventArgs.cs
- DbMetaDataFactory.cs
- OptimizedTemplateContent.cs
- AttachedPropertyBrowsableForChildrenAttribute.cs
- CellTreeNodeVisitors.cs
- Activator.cs
- DataServiceConfiguration.cs
- SchemaTableOptionalColumn.cs
- ProxyGenerator.cs
- FrameDimension.cs
- ArglessEventHandlerProxy.cs
- OrCondition.cs
- ValidationEventArgs.cs
- ClientData.cs
- DateTime.cs
- input.cs
- XmlLinkedNode.cs
- SynchronousChannel.cs
- HttpMethodConstraint.cs
- PathParser.cs
- ScalarType.cs
- MultipleViewProviderWrapper.cs
- GeneralTransform3D.cs
- XmlArrayItemAttribute.cs
- FilterableAttribute.cs
- WebResponse.cs
- CompositeControl.cs
- JpegBitmapDecoder.cs
- DesignerActionMethodItem.cs
- WebPartConnectionsDisconnectVerb.cs
- sitestring.cs
- HttpWebResponse.cs
- XsdValidatingReader.cs
- MetricEntry.cs
- BypassElementCollection.cs
- RelativeSource.cs
- BasicCommandTreeVisitor.cs
- XmlSchemaCompilationSettings.cs
- DesignerCategoryAttribute.cs
- WindowsScroll.cs
- XslTransform.cs
- SafeHandles.cs
- NameValueConfigurationElement.cs
- ECDiffieHellmanPublicKey.cs
- WindowsListViewItemStartMenu.cs