Code:
/ Net / Net / 3.5.50727.3053 / DEVDIV / depot / DevDiv / releases / whidbey / netfxsp / ndp / clr / src / BCL / System / Globalization / AgileSafeNativeMemoryHandle.cs / 2 / 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
- InfocardExtendedInformationCollection.cs
- GenericRootAutomationPeer.cs
- MultiSelector.cs
- DataGridViewTextBoxCell.cs
- DiscoveryServiceExtension.cs
- TimeSpanSecondsConverter.cs
- MouseActionValueSerializer.cs
- TrackingMemoryStream.cs
- Highlights.cs
- PermissionListSet.cs
- CodeConditionStatement.cs
- CompilerScopeManager.cs
- ToolTip.cs
- WebBrowserPermission.cs
- TrackingStringDictionary.cs
- DaylightTime.cs
- InputScope.cs
- StatusBarPanel.cs
- RegisteredHiddenField.cs
- ListViewItem.cs
- DataGridTextBox.cs
- HttpConfigurationSystem.cs
- StringComparer.cs
- Cursor.cs
- SessionStateItemCollection.cs
- Label.cs
- SqlCaseSimplifier.cs
- SigningDialog.cs
- Timeline.cs
- LocalizationComments.cs
- NotificationContext.cs
- LogLogRecord.cs
- StylusTouchDevice.cs
- OleDbRowUpdatedEvent.cs
- ImmutablePropertyDescriptorGridEntry.cs
- VolatileResourceManager.cs
- RectangleF.cs
- RawStylusInputCustomData.cs
- TextComposition.cs
- AesCryptoServiceProvider.cs
- SecurityCriticalDataForSet.cs
- MetadataArtifactLoaderResource.cs
- TextFormatter.cs
- IndependentAnimationStorage.cs
- OLEDB_Enum.cs
- EventLogWatcher.cs
- BindingWorker.cs
- BounceEase.cs
- ConfigurationElementCollection.cs
- DataGridViewRowPostPaintEventArgs.cs
- ObjectDataSourceEventArgs.cs
- StylusPointCollection.cs
- XPathException.cs
- ProvidersHelper.cs
- WpfPayload.cs
- ACE.cs
- OLEDB_Enum.cs
- ZipArchive.cs
- FormViewInsertedEventArgs.cs
- ExtensionWindowHeader.cs
- CreateUserErrorEventArgs.cs
- Font.cs
- RoleManagerEventArgs.cs
- MachineKeyConverter.cs
- DesignerSerializerAttribute.cs
- JpegBitmapEncoder.cs
- ProcessProtocolHandler.cs
- ApplicationServiceHelper.cs
- MorphHelper.cs
- XmlReader.cs
- wmiutil.cs
- Utils.cs
- DefaultTextStoreTextComposition.cs
- Int32Converter.cs
- MissingMethodException.cs
- _SingleItemRequestCache.cs
- XmlTypeMapping.cs
- cookieexception.cs
- TimeSpan.cs
- CodeParameterDeclarationExpressionCollection.cs
- HttpHandlersSection.cs
- KeyedCollection.cs
- CreateParams.cs
- UndoEngine.cs
- SchemaAttDef.cs
- SqlConnection.cs
- SafeSerializationManager.cs
- NumericUpDownAcceleration.cs
- ZipIOZip64EndOfCentralDirectoryBlock.cs
- RowCache.cs
- MetadataArtifactLoaderCompositeResource.cs
- NamespaceList.cs
- DetailsViewUpdatedEventArgs.cs
- MSAAWinEventWrap.cs
- Style.cs
- ResourceType.cs
- MexHttpsBindingElement.cs
- HttpModuleActionCollection.cs
- NotificationContext.cs
- SourceChangedEventArgs.cs