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using System;
using System.ComponentModel;
using System.Text;
using System.Globalization;
using MS.Win32;
using System.Runtime.InteropServices;
using System.Resources;
using System.IO;
using System.Security;
using System.Security.Permissions;
using SecurityHelper=MS.Internal.SecurityHelper;
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID;
using MS.Internal.PresentationCore; // FriendAccessAllowed
namespace System.Windows.Input
{
/// <summary>
/// Cursor class to support default cursor types.
/// TBD: Support for cutomized cursor types.
/// </summary>
[TypeConverter(typeof(CursorConverter))]
[Localizability(LocalizationCategory.None, Readability = Readability.Unreadable)]
public sealed class Cursor : IDisposable
{
/// <summary>
/// Constructor for Standard Cursors, needn't be public as Stock Cursors
/// are exposed in Cursors clas.
/// </summary>
/// <param name="cursorType"></param>
internal Cursor(CursorType cursorType)
{
if (IsValidCursorType(cursorType))
{
LoadCursorHelper(cursorType);
}
else
{
throw new ArgumentException(SR.Get(SRID.InvalidCursorType, cursorType));
}
}
/// <summary>
/// Cursor from .ani or .cur file
/// </summary>
/// <param name="cursorFile"></param>
public Cursor(string cursorFile):this(cursorFile, false)
{
}
/// <summary>
/// Cursor from .ani or .cur file
/// </summary>
/// <param name="cursorFile"></param>
/// <param name="scaleWithDpi"></param>
public Cursor(string cursorFile, bool scaleWithDpi)
{
_scaleWithDpi = scaleWithDpi;
if (cursorFile == null)
throw new ArgumentNullException("cursorFile");
if ((cursorFile != String.Empty) &&
(cursorFile.EndsWith(".cur", StringComparison.OrdinalIgnoreCase) ||
cursorFile.EndsWith(".ani", StringComparison.OrdinalIgnoreCase)))
{
LoadFromFile(cursorFile);
_fileName = cursorFile;
}
else
{
throw new ArgumentException(SR.Get(SRID.Cursor_UnsupportedFormat , cursorFile));
}
}
/// <summary>
/// Cursor from Stream
/// </summary>
/// <param name="cursorStream"></param>
public Cursor(Stream cursorStream):this(cursorStream, false)
{
}
/// <summary>
/// Cursor from Stream
/// </summary>
/// <param name="cursorStream"></param>
/// <param name="scaleWithDpi"></param>
public Cursor(Stream cursorStream, bool scaleWithDpi)
{
_scaleWithDpi = scaleWithDpi;
if (cursorStream == null)
{
throw new ArgumentNullException("cursorStream");
}
LoadFromStream(cursorStream);
}
/// <summary>
/// Cursor from a SafeHandle to an HCURSOR
/// </summary>
/// <param name="cursorHandle"></param>
/// <SecurityNote>
/// Critical: Sets _cursorHandle, which is of a SecurityCritical type. (V4 transparency enforcement)
/// TreatAsSafe: This code is safe to expose because in the worst case you change cursor for your app
/// See SecurityNote on _cursorHandle.
/// </SecurityNote>
[SecurityCritical,SecurityTreatAsSafe]
[FriendAccessAllowed] //used by ColumnHeader.GetCursor in PresentationFramework
internal Cursor(SafeHandle cursorHandle )
{
if (! cursorHandle.IsInvalid )
{
this._cursorHandle = cursorHandle ;
}
}
/// <summary>
/// Destructor (IDispose pattern)
/// </summary>
~Cursor()
{
Dispose(false);
}
/// <summary>
/// Cleans up the resources allocated by this object. Once called, the cursor
/// object is no longer useful.
/// </summary>
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
/// <SecurityNote>
/// Critical: SafeHandle code link demands on dispose.
/// TreatAsSafe: Safe to dispose a cursor.
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe ]
void Dispose(bool disposing)
{
if ( _cursorHandle != null )
{
_cursorHandle.Dispose();
_cursorHandle = null;
}
}
/// <summary>
/// CursorType - Cursor Type Enumeration
/// </summary>
/// <value></value>
internal CursorType CursorType
{
get
{
return _cursorType;
}
}
/// <summary>
/// Handle - HCURSOR Interop
/// </summary>
/// <value></value>
/// <SecurityNote>
/// Critical: Returns a SafeHandle, which is a SecurityCritical type in v4.
/// See SecurityNote on _cursorHandle.
/// </SecurityNote>
internal SafeHandle Handle
{
[SecurityCritical]
get
{
return _cursorHandle ?? NativeMethods.CursorHandle.GetInvalidCursor();
}
}
/// <summary>
/// FileName - .ani or .cur files are allowed
/// </summary>
/// <value></value>
internal String FileName
{
get
{
return _fileName;
}
}
///<SecurityNote>
/// Critical: 1) Access to a file. Calls Win32Exception ctor, which LinkDemands.
/// Method success/failure could be used to do local file path probing.
/// 2) Sets _cursorHandle, which is of a SecurityCritical type.
/// TreatAsSafe: 1) We demand FileIOPermission. Then it's okay to throw an exception about any failure.
/// 2) Anyone is allowed to set the cursor. See SecurityNote on _cursorHandle.
///</SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
private void LoadFromFile(string fileName)
{
SecurityHelper.DemandFileIOReadPermission(fileName);
// Load a Custom Cursor
_cursorHandle = UnsafeNativeMethods.LoadImageCursor(IntPtr.Zero,
fileName,
NativeMethods.IMAGE_CURSOR,
0, 0,
NativeMethods.LR_DEFAULTCOLOR |
NativeMethods.LR_LOADFROMFILE |
(_scaleWithDpi? NativeMethods.LR_DEFAULTSIZE : 0x0000));
int errorCode = Marshal.GetLastWin32Error();
if (_cursorHandle == null || _cursorHandle.IsInvalid)
{
// Note: chandras 02/02/2005
// Bug # 1016022: LoadImage returns a null handle but does not set
// the error condition when icon file is of an incorrect type (e.g., .bmp)
//
// LoadImage has a bug where it doesn't set the correct error code
// when a file is given that is not an ico file. Icon load fails
// but win32 error code is still zero (success). Thus, we need to
// special case this scenario.
//
if (errorCode != 0)
{
if ((errorCode == NativeMethods.ERROR_FILE_NOT_FOUND) || (errorCode == NativeMethods.ERROR_PATH_NOT_FOUND))
{
throw new Win32Exception(errorCode, SR.Get(SRID.Cursor_LoadImageFailure, fileName));
}
else
{
throw new Win32Exception(errorCode);
}
}
else
{
throw new ArgumentException(SR.Get(SRID.Cursor_LoadImageFailure, fileName));
}
}
}
//**** DEAD CODE - retained only for compat, if user sets quirk flag ****
private const int BUFFERSIZE = 4096; // the maximum size of the buffer used for loading from stream
/// <SecurityNote>
/// Critical: Sets _cursorHandle, which is of a SecurityCritical type.
/// TreatAsSafe: Anyone is allowed to set the cursor. See SecurityNote on _cursorHandle.
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
private void LegacyLoadFromStream(Stream cursorStream)
{
//Generate a temporal file based on the memory stream.
//
string filePath = Path.GetTempFileName();
try
{
using (BinaryReader reader = new BinaryReader(cursorStream))
{
using (FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Write, FileShare.None))
{
// Read the bytes from the stream, up to BUFFERSIZE
byte[] cursorData = reader.ReadBytes(BUFFERSIZE);
int dataSize;
// If the buffer is filled up, then write those bytes out and read more bytes up to BUFFERSIZE
for (dataSize = cursorData.Length;
dataSize >= BUFFERSIZE;
dataSize = reader.Read(cursorData, 0 /*index in array*/, BUFFERSIZE /*bytes to read*/))
{
fileStream.Write(cursorData, 0 /*index in array*/, BUFFERSIZE /*bytes to write*/);
}
// Write any remaining bytes
fileStream.Write(cursorData, 0 /*index in array*/, dataSize /*bytes to write*/);
}
}
// This method is called with File Write permission still asserted.
// However, this method just reads this file into an icon.
_cursorHandle = UnsafeNativeMethods.LoadImageCursor(IntPtr.Zero,
filePath,
NativeMethods.IMAGE_CURSOR,
0, 0,
NativeMethods.LR_DEFAULTCOLOR |
NativeMethods.LR_LOADFROMFILE |
(_scaleWithDpi? NativeMethods.LR_DEFAULTSIZE : 0x0000));
if (_cursorHandle == null || _cursorHandle.IsInvalid)
{
throw new ArgumentException(SR.Get(SRID.Cursor_InvalidStream));
}
}
finally
{
try
{
File.Delete(filePath);
}
catch(System.IO.IOException)
{
// DDVSO 227517: We may not be able to delete the file if it's being used by some other process (e.g. Anti-virus check).
// There's nothing we can do in that case, so just eat the exception and leave the file behind
}
}
}
//**** end of DEAD CODE ****//
/// <SecurityNote>
/// Critical: Sets _cursorHandle, which is of a SecurityCritical type.
/// TreatAsSafe: Anyone is allowed to set the cursor. See SecurityNote on _cursorHandle.
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
private void LoadFromStream(Stream cursorStream)
{
if (MS.Internal.CoreAppContextSwitches.AllowExternalProcessToBlockAccessToTemporaryFiles)
{
LegacyLoadFromStream(cursorStream);
return;
}
string filePath = null;
try
{
// Generate a temporary file based on the memory stream.
using (FileStream fileStream = FileHelper.CreateAndOpenTemporaryFile(out filePath))
{
cursorStream.CopyTo(fileStream);
}
// create a cursor from the temp file
_cursorHandle = UnsafeNativeMethods.LoadImageCursor(IntPtr.Zero,
filePath,
NativeMethods.IMAGE_CURSOR,
0, 0,
NativeMethods.LR_DEFAULTCOLOR |
NativeMethods.LR_LOADFROMFILE |
(_scaleWithDpi? NativeMethods.LR_DEFAULTSIZE : 0x0000));
if (_cursorHandle == null || _cursorHandle.IsInvalid)
{
throw new ArgumentException(SR.Get(SRID.Cursor_InvalidStream));
}
}
finally
{
FileHelper.DeleteTemporaryFile(filePath);
}
}
/// <SecurityNote>
/// Critical: Sets _cursorHandle, which is of a SecurityCritical type.
/// TreatAsSafe: Anyone is allowed to set the cursor. See SecurityNote on _cursorHandle.
/// </SecurityNote>
[SecurityCritical, SecurityTreatAsSafe]
private void LoadCursorHelper(CursorType cursorType)
{
if (cursorType != CursorType.None)
{
// Load a Standard Cursor
_cursorHandle = SafeNativeMethods.LoadCursor(new HandleRef(this,IntPtr.Zero), (IntPtr)(CursorTypes[(int)cursorType]));
}
this._cursorType = cursorType;
}
/// <summary>
/// String Output
///
public override string ToString()
{
if (_fileName != String.Empty)
return _fileName;
else
{
// Get the string representation fo the cursor type enumeration.
return Enum.GetName(typeof(CursorType), _cursorType);
}
}
private bool IsValidCursorType(CursorType cursorType)
{
return ((int)cursorType >= (int)CursorType.None && (int)cursorType <= (int)CursorType.ArrowCD);
}
private string _fileName = String.Empty;
private CursorType _cursorType = CursorType.None;
private bool _scaleWithDpi = false;
/// <SecurityNote>
/// In v4, SafeHandle is marked as SecurityCritical. According to the new transparency enforcement model,
/// any access to this field must be done from a SecurityCritical method (even though our assemblies still
/// use the v2 model). However, we don't consider setting/replacing the cursor a critical operation.
/// (Effect is only within the application's UI.) That's why TreatAsSafe methods are allowed to set this
/// field. Individual methods on SafeHandle still guard access to the OS handle.
/// </SecurityNote>
[SecurityCritical]
private SafeHandle _cursorHandle;
private static readonly int[] CursorTypes = {
0, // None
NativeMethods.IDC_NO,
NativeMethods.IDC_ARROW,
NativeMethods.IDC_APPSTARTING,
NativeMethods.IDC_CROSS,
NativeMethods.IDC_HELP,
NativeMethods.IDC_IBEAM,
NativeMethods.IDC_SIZEALL,
NativeMethods.IDC_SIZENESW,
NativeMethods.IDC_SIZENS,
NativeMethods.IDC_SIZENWSE,
NativeMethods.IDC_SIZEWE,
NativeMethods.IDC_UPARROW,
NativeMethods.IDC_WAIT,
NativeMethods.IDC_HAND,
NativeMethods.IDC_ARROW + 119, // PenCursor
NativeMethods.IDC_ARROW + 140, // ScrollNSCursor
NativeMethods.IDC_ARROW + 141, // ScrollWECursor
NativeMethods.IDC_ARROW + 142, // ScrollAllCursor
NativeMethods.IDC_ARROW + 143, // ScrollNCursor
NativeMethods.IDC_ARROW + 144, // ScrollSCursor
NativeMethods.IDC_ARROW + 145, // ScrollWCursor
NativeMethods.IDC_ARROW + 146, // ScrollECursor
NativeMethods.IDC_ARROW + 147, // ScrollNWCursor
NativeMethods.IDC_ARROW + 148, // ScrollNECursor
NativeMethods.IDC_ARROW + 149, // ScrollSWCursor
NativeMethods.IDC_ARROW + 150, // ScrollSECursor
NativeMethods.IDC_ARROW + 151 // ArrowCDCursor
};
}
}
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