Code:
/ Dotnetfx_Win7_3.5.1 / Dotnetfx_Win7_3.5.1 / 3.5.1 / DEVDIV / depot / DevDiv / releases / whidbey / NetFXspW7 / ndp / clr / src / BCL / System / Globalization / AgileSafeNativeMemoryHandle.cs / 1 / AgileSafeNativeMemoryHandle.cs
// ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== /*============================================================ ** ** Class: AgileSafeNativeMemoryHandle ** ** This class is to hold native memory handle and make sure it ** gets released when the object get collected by GC. ** ** This class can hold one of two types of memory handle ** first it can hold a handle for memory created using ** Marshal.AllocHGlobal. this can happen when creating ** the object using constructor taking IntPtr as handle. ** in this case mode = false. ** ** second it can hold handle for memory created from mapped ** file. this can happen when creating the object using the ** file name then the constructor will open and map this file ** and hold the mapped memory section handle ** in this case mode = true. ** ** IMPORTANT IMPORTANT IMPORTANT IMPORTANT IMPORTANT IMPORTANT ** this class is used only with CultureInfo or its ** field classes. ** this class is special case that is agile and has finalizer ** and it is a special case like Thread class. ** this class is agile to make sure it survive the app domain ** unloading. otherwise we can get AV when culture info cross ** the app domain boundary. ** so don't use it in any other purpose. ** ===========================================================*/ using System; using System.IO; using System.Security; using System.Security.Permissions; using System.Runtime.InteropServices; using System.Runtime.CompilerServices; using System.Runtime.ConstrainedExecution; using Microsoft.Win32; using Microsoft.Win32.SafeHandles; using System.Runtime.Versioning; namespace System.Globalization { internal sealed class AgileSafeNativeMemoryHandle : SafeHandleZeroOrMinusOneIsInvalid { private const int PAGE_READONLY = 0x02; private const int SECTION_MAP_READ = 0x0004; private unsafe byte* bytes; // // The only handle we keep it open is the mapped memory section and we close // both the stream and mapped file handle as the OS keep the memory section // mapped even when closing the files. // The benefit for closing the file and stream handle is have flexability // to rename the file while it is in use. // private long fileSize = 0; // mode is true if the memory created from mapped file. // and false if the memory created from Marshal.AllocHGlobal. private bool mode = false; [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode=true)] internal AgileSafeNativeMemoryHandle() : base(true) {} [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode=true)] internal AgileSafeNativeMemoryHandle(IntPtr handle, bool ownsHandle) : base (ownsHandle) { SetHandle(handle); } [ResourceExposure(ResourceScope.Machine)] [ResourceConsumption(ResourceScope.Machine)] internal unsafe AgileSafeNativeMemoryHandle(String fileName) : this(fileName, null) {} [ResourceExposure(ResourceScope.Machine)] [ResourceConsumption(ResourceScope.Machine)] internal unsafe AgileSafeNativeMemoryHandle(String fileName, String fileMappingName) : base(true) { mode = true; // // Use native API to create the file directly. // SafeFileHandle fileHandle = Win32Native.UnsafeCreateFile(fileName, FileStream.GENERIC_READ, FileShare.Read, null, FileMode.Open, 0, IntPtr.Zero); int lastError = Marshal.GetLastWin32Error(); if (fileHandle.IsInvalid) { BCLDebug.Assert(false, "Failed to create file " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } int highSize; int lowSize = Win32Native.GetFileSize(fileHandle, out highSize); if (lowSize == Win32Native.INVALID_FILE_SIZE) { fileHandle.Close(); BCLDebug.Assert(false, "Failed to get the file size of " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } fileSize = (((long) highSize) << 32) | ((uint) lowSize); if (fileSize == 0) { // we cannot map zero size file. the caller should check for the file size. fileHandle.Close(); return; } SafeFileMappingHandle fileMapHandle = Win32Native.CreateFileMapping(fileHandle, IntPtr.Zero, PAGE_READONLY, 0, 0, fileMappingName); lastError = Marshal.GetLastWin32Error(); fileHandle.Close(); if (fileMapHandle.IsInvalid) { BCLDebug.Assert(false, "Failed to create file mapping for file " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } // Use a CER to ensure that we store the handle within this SafeHandle without allowing async exceptions. RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { handle = Win32Native.MapViewOfFile(fileMapHandle, SECTION_MAP_READ, 0, 0, UIntPtr.Zero); } lastError = Marshal.GetLastWin32Error(); if (handle == IntPtr.Zero) { fileMapHandle.Close(); BCLDebug.Assert(false, "Failed to map a view of file " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } bytes = (byte*) this.DangerousGetHandle(); fileMapHandle.Close(); } internal long FileSize { get { BCLDebug.Assert(mode == true, "The memory is not created from mapped file to request the size"); return fileSize; } } internal unsafe byte* GetBytePtr() { BCLDebug.Assert(bytes != null && mode == true, "bytes can requested only if the memory created from mapped file"); return (bytes); } override protected bool ReleaseHandle() { if (!IsInvalid) { if (mode == true) { if (Win32Native.UnmapViewOfFile(handle)) { handle = IntPtr.Zero; return true; } } else { Marshal.FreeHGlobal(handle); handle = IntPtr.Zero; return true; } } return false; } } } // File provided for Reference Use Only by Microsoft Corporation (c) 2007. // ==++== // // Copyright (c) Microsoft Corporation. All rights reserved. // // ==--== /*============================================================ ** ** Class: AgileSafeNativeMemoryHandle ** ** This class is to hold native memory handle and make sure it ** gets released when the object get collected by GC. ** ** This class can hold one of two types of memory handle ** first it can hold a handle for memory created using ** Marshal.AllocHGlobal. this can happen when creating ** the object using constructor taking IntPtr as handle. ** in this case mode = false. ** ** second it can hold handle for memory created from mapped ** file. this can happen when creating the object using the ** file name then the constructor will open and map this file ** and hold the mapped memory section handle ** in this case mode = true. ** ** IMPORTANT IMPORTANT IMPORTANT IMPORTANT IMPORTANT IMPORTANT ** this class is used only with CultureInfo or its ** field classes. ** this class is special case that is agile and has finalizer ** and it is a special case like Thread class. ** this class is agile to make sure it survive the app domain ** unloading. otherwise we can get AV when culture info cross ** the app domain boundary. ** so don't use it in any other purpose. ** ===========================================================*/ using System; using System.IO; using System.Security; using System.Security.Permissions; using System.Runtime.InteropServices; using System.Runtime.CompilerServices; using System.Runtime.ConstrainedExecution; using Microsoft.Win32; using Microsoft.Win32.SafeHandles; using System.Runtime.Versioning; namespace System.Globalization { internal sealed class AgileSafeNativeMemoryHandle : SafeHandleZeroOrMinusOneIsInvalid { private const int PAGE_READONLY = 0x02; private const int SECTION_MAP_READ = 0x0004; private unsafe byte* bytes; // // The only handle we keep it open is the mapped memory section and we close // both the stream and mapped file handle as the OS keep the memory section // mapped even when closing the files. // The benefit for closing the file and stream handle is have flexability // to rename the file while it is in use. // private long fileSize = 0; // mode is true if the memory created from mapped file. // and false if the memory created from Marshal.AllocHGlobal. private bool mode = false; [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode=true)] internal AgileSafeNativeMemoryHandle() : base(true) {} [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode=true)] internal AgileSafeNativeMemoryHandle(IntPtr handle, bool ownsHandle) : base (ownsHandle) { SetHandle(handle); } [ResourceExposure(ResourceScope.Machine)] [ResourceConsumption(ResourceScope.Machine)] internal unsafe AgileSafeNativeMemoryHandle(String fileName) : this(fileName, null) {} [ResourceExposure(ResourceScope.Machine)] [ResourceConsumption(ResourceScope.Machine)] internal unsafe AgileSafeNativeMemoryHandle(String fileName, String fileMappingName) : base(true) { mode = true; // // Use native API to create the file directly. // SafeFileHandle fileHandle = Win32Native.UnsafeCreateFile(fileName, FileStream.GENERIC_READ, FileShare.Read, null, FileMode.Open, 0, IntPtr.Zero); int lastError = Marshal.GetLastWin32Error(); if (fileHandle.IsInvalid) { BCLDebug.Assert(false, "Failed to create file " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } int highSize; int lowSize = Win32Native.GetFileSize(fileHandle, out highSize); if (lowSize == Win32Native.INVALID_FILE_SIZE) { fileHandle.Close(); BCLDebug.Assert(false, "Failed to get the file size of " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } fileSize = (((long) highSize) << 32) | ((uint) lowSize); if (fileSize == 0) { // we cannot map zero size file. the caller should check for the file size. fileHandle.Close(); return; } SafeFileMappingHandle fileMapHandle = Win32Native.CreateFileMapping(fileHandle, IntPtr.Zero, PAGE_READONLY, 0, 0, fileMappingName); lastError = Marshal.GetLastWin32Error(); fileHandle.Close(); if (fileMapHandle.IsInvalid) { BCLDebug.Assert(false, "Failed to create file mapping for file " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } // Use a CER to ensure that we store the handle within this SafeHandle without allowing async exceptions. RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { handle = Win32Native.MapViewOfFile(fileMapHandle, SECTION_MAP_READ, 0, 0, UIntPtr.Zero); } lastError = Marshal.GetLastWin32Error(); if (handle == IntPtr.Zero) { fileMapHandle.Close(); BCLDebug.Assert(false, "Failed to map a view of file " + fileName + ", GetLastError = " + lastError); throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidOperation_UnexpectedWin32Error"), lastError)); } bytes = (byte*) this.DangerousGetHandle(); fileMapHandle.Close(); } internal long FileSize { get { BCLDebug.Assert(mode == true, "The memory is not created from mapped file to request the size"); return fileSize; } } internal unsafe byte* GetBytePtr() { BCLDebug.Assert(bytes != null && mode == true, "bytes can requested only if the memory created from mapped file"); return (bytes); } override protected bool ReleaseHandle() { if (!IsInvalid) { if (mode == true) { if (Win32Native.UnmapViewOfFile(handle)) { handle = IntPtr.Zero; return true; } } else { Marshal.FreeHGlobal(handle); handle = IntPtr.Zero; return true; } } return false; } } } // 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
- OdbcInfoMessageEvent.cs
- ResolveDuplex11AsyncResult.cs
- DataGridItemCollection.cs
- OleDbError.cs
- mactripleDES.cs
- XmlWriterSettings.cs
- CapabilitiesPattern.cs
- BaseValidator.cs
- URLString.cs
- PeerEndPoint.cs
- TabPanel.cs
- HtmlDocument.cs
- SoapAttributeAttribute.cs
- ExceptionCollection.cs
- Int64KeyFrameCollection.cs
- SiteMapNodeItem.cs
- EntityDataReader.cs
- FrameworkContentElementAutomationPeer.cs
- PresentationUIStyleResources.cs
- ThreadPool.cs
- CodeNamespaceImport.cs
- CollectionsUtil.cs
- FieldTemplateUserControl.cs
- SqlProfileProvider.cs
- SelectedCellsChangedEventArgs.cs
- FormViewInsertEventArgs.cs
- XmlWrappingReader.cs
- HtmlTextArea.cs
- SHA1.cs
- OleDbParameter.cs
- Rfc2898DeriveBytes.cs
- ListControl.cs
- AttachedPropertyBrowsableWhenAttributePresentAttribute.cs
- Blend.cs
- ToolStripTextBox.cs
- ActivationArguments.cs
- PathGeometry.cs
- AffineTransform3D.cs
- Knowncolors.cs
- ModuleConfigurationInfo.cs
- BindingExpressionUncommonField.cs
- App.cs
- TdsEnums.cs
- DataAdapter.cs
- _ScatterGatherBuffers.cs
- ConnectAlgorithms.cs
- PenThread.cs
- TransformCollection.cs
- VersionValidator.cs
- TextRange.cs
- SharedDp.cs
- MailMessage.cs
- LoadedOrUnloadedOperation.cs
- GlobalAllocSafeHandle.cs
- PropertyBuilder.cs
- SiteMapSection.cs
- SwitchElementsCollection.cs
- ResourceDictionary.cs
- Dispatcher.cs
- DataRecordInternal.cs
- DefaultAsyncDataDispatcher.cs
- EncryptedData.cs
- SharedConnectionInfo.cs
- ExpressionEditorAttribute.cs
- PolyQuadraticBezierSegment.cs
- SubqueryRules.cs
- Decimal.cs
- DataTemplateKey.cs
- DirectionalLight.cs
- OverflowException.cs
- CheckableControlBaseAdapter.cs
- QilReplaceVisitor.cs
- ConstrainedDataObject.cs
- PointAnimationClockResource.cs
- CompressEmulationStream.cs
- X509CertificateValidator.cs
- CodeDOMUtility.cs
- TimeSpanFormat.cs
- SyncMethodInvoker.cs
- StreamGeometry.cs
- FacetDescriptionElement.cs
- ProcessHost.cs
- Buffer.cs
- DllHostInitializer.cs
- RoutingUtilities.cs
- FontDialog.cs
- SchemaCreator.cs
- HMACSHA384.cs
- WebContentFormatHelper.cs
- DataSourceListEditor.cs
- IconConverter.cs
- ColorKeyFrameCollection.cs
- PeerName.cs
- HMACMD5.cs
- ObjectDataSourceChooseMethodsPanel.cs
- PersonalizableTypeEntry.cs
- SerializationSectionGroup.cs
- InputReferenceExpression.cs
- GlyphTypeface.cs
- CommaDelimitedStringAttributeCollectionConverter.cs