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
- ApplicationInfo.cs
- DbParameterHelper.cs
- IndexedSelectQueryOperator.cs
- KeyInfo.cs
- DictionaryEntry.cs
- EntityException.cs
- SafeFileMappingHandle.cs
- CommandEventArgs.cs
- SiteOfOriginContainer.cs
- DataGridViewLinkCell.cs
- DrawTreeNodeEventArgs.cs
- DataColumnChangeEvent.cs
- RIPEMD160Managed.cs
- Size.cs
- UriSection.cs
- AssociationSetMetadata.cs
- _KerberosClient.cs
- SerializationSectionGroup.cs
- ByteStorage.cs
- Listbox.cs
- DataRowCollection.cs
- dsa.cs
- IriParsingElement.cs
- WebServiceParameterData.cs
- HttpCachePolicy.cs
- ActivityMarkupSerializationProvider.cs
- FileChangesMonitor.cs
- OpenFileDialog.cs
- XmlChildNodes.cs
- Vector3D.cs
- Vector3DAnimation.cs
- TimeSpanMinutesConverter.cs
- WinFormsComponentEditor.cs
- VarRemapper.cs
- Block.cs
- WebPartConnectionsCloseVerb.cs
- CodeMethodInvokeExpression.cs
- AssemblyAttributes.cs
- CompilerScopeManager.cs
- Helper.cs
- CompositeFontFamily.cs
- DocumentApplicationJournalEntry.cs
- VersionedStream.cs
- ToolStripSeparatorRenderEventArgs.cs
- SafeProcessHandle.cs
- FreeFormPanel.cs
- Module.cs
- QilTernary.cs
- InputBindingCollection.cs
- ImplicitInputBrush.cs
- StringConcat.cs
- RsaElement.cs
- Wildcard.cs
- CheckBoxFlatAdapter.cs
- BindingMAnagerBase.cs
- ToolStripInSituService.cs
- TextStore.cs
- EventBuilder.cs
- ProcessModuleCollection.cs
- DtrList.cs
- SqlMethods.cs
- NavigationWindow.cs
- Oid.cs
- WebBrowserPermission.cs
- NameValueCollection.cs
- DataGridViewRowsRemovedEventArgs.cs
- Util.cs
- ImageSourceConverter.cs
- OrderedEnumerableRowCollection.cs
- ClientConfigPaths.cs
- TransformerConfigurationWizardBase.cs
- PenThreadWorker.cs
- UniqueEventHelper.cs
- GeneralTransform.cs
- HttpCapabilitiesBase.cs
- ClipboardData.cs
- EventHandlers.cs
- NativeMethods.cs
- SortQuery.cs
- Comparer.cs
- Point3D.cs
- InfoCardRequestException.cs
- CompoundFileIOPermission.cs
- Stack.cs
- GPPOINT.cs
- basecomparevalidator.cs
- LineMetrics.cs
- FullTrustAssemblyCollection.cs
- DCSafeHandle.cs
- SplitterEvent.cs
- KeyTime.cs
- MulticastDelegate.cs
- SvcMapFile.cs
- XmlRootAttribute.cs
- DependencyObjectProvider.cs
- SQLString.cs
- DataObjectAttribute.cs
- GradientStop.cs
- FindSimilarActivitiesVerb.cs
- AmbientLight.cs