internal static SafeFileHandle GetFileHandle(string normalizedPath, FileMode mode, FileAccess access, FileShare share, FileOptions options)
{
bool append = mode == FileMode.Append;
if (append)
{
mode = FileMode.OpenOrCreate;
}
NativeMethods.EFileAccess underlyingAccess = GetUnderlyingAccess(access);
SafeFileHandle handle = NativeMethods.CreateFile(normalizedPath, underlyingAccess, (uint)share, IntPtr.Zero, (uint)mode, (uint)options, IntPtr.Zero);
if (handle.IsInvalid)
{
Exception ex = Common.GetExceptionFromLastWin32Error();
Debug.WriteLine(string.Format("error {0} with {1}{3}{2}", ex.Message, normalizedPath, ex.StackTrace, Environment.NewLine));
Debug.WriteLine(string.Format("{0} {1} {2} {3}", mode, access, share, options));
throw ex;
}
if (append)
{
NativeMethods.SetFilePointer(handle, 0, SeekOrigin.End);
}
return(handle);
}
private static SafeFileHandle CreateFileHandle(
string devicePath,
NativeMethods.EFileAccess desiredAccess = 0, // If this parameter is zero, can query certain metadata without accessing device
NativeMethods.EFileAttributes fileAttribs = 0 // Use overlapped IO?
)
{
// Default security attributes
var security = new NativeMethods.SECURITY_ATTRIBUTES
{
lpSecurityDescriptor = IntPtr.Zero,
bInheritHandle = true,
nLength = Marshal.SizeOf(typeof(NativeMethods.SECURITY_ATTRIBUTES))
};
// Get safe handle to device
var handle = NativeMethods.CreateFile(devicePath,
desiredAccess,
NativeMethods.EFileShare.Read | NativeMethods.EFileShare.Write,
ref security,
NativeMethods.ECreationDisposition.OpenExisting,
fileAttribs,
IntPtr.Zero);
// Throw exception if handle isn't valid
if (handle.IsInvalid)
{
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
// Return handle
return(handle);
}
public static extern SafeFileHandle CreateFile(
string lpFileName,
NativeMethods.EFileAccess dwDesiredAccess,
NativeMethods.EFileShare dwShareMode,
IntPtr lpSecurityAttributes,
NativeMethods.ECreationDisposition dwCreationDisposition,
NativeMethods.EFileAttributes dwFlagsAndAttributes,
IntPtr hTemplateFile);
private static SafeFileHandle GetFileHandle(string normalizedPath, FileMode mode, FileAccess access, FileShare share, FileOptions options)
{
NativeMethods.EFileAccess underlyingAccess = GetUnderlyingAccess(access);
SafeFileHandle handle = NativeMethods.CreateFile(normalizedPath, underlyingAccess, (uint)share, IntPtr.Zero, (uint)mode, (uint)options, IntPtr.Zero);
if (handle.IsInvalid)
{
throw LongPathCommon.GetExceptionFromLastWin32Error();
}
return(handle);
}
private static SafeFileHandle OpenReparsePoint(string reparsePoint, NativeMethods.EFileAccess accessMode)
{
SafeFileHandle reparsePointHandle = NativeMethods.CreateFile(reparsePoint, accessMode,
NativeMethods.EFileShare.Read | NativeMethods.EFileShare.Write | NativeMethods.EFileShare.Delete,
IntPtr.Zero, NativeMethods.ECreationDisposition.OpenExisting,
NativeMethods.EFileAttributes.BackupSemantics | NativeMethods.EFileAttributes.OpenReparsePoint, IntPtr.Zero);
if (Marshal.GetLastWin32Error() != 0)
{
ThrowLastWin32Error("Resources.UnableToOpenReparsePoint");
}
return(reparsePointHandle);
}
/// <summary>
/// Creates or overwrites the file at the specified path.
/// </summary>
/// <param name="path">The path and name of the file to create. Supports long file paths.</param>
/// <returns>A <see cref="System.IO.Stream"/> that provides read/write access to the file specified in path.</returns>
public override System.IO.Stream CreateFile(Path path)
{
if (path.IsEmpty)
{
throw new ArgumentNullException("path");
}
NativeMethods.EFileAccess fileAccess = NativeMethods.EFileAccess.GenericWrite | NativeMethods.EFileAccess.GenericRead;
NativeMethods.EFileShare fileShareMode = NativeMethods.EFileShare.None;//exclusive
NativeMethods.ECreationDisposition creationDisposition = NativeMethods.ECreationDisposition.CreateAlways;
SafeFileHandle hFile = NativeMethods.CreateFile(path.WithWin32LongPathPrefix(), fileAccess, fileShareMode, IntPtr.Zero, creationDisposition, NativeMethods.EFileAttributes.Normal, IntPtr.Zero);
if (hFile.IsInvalid)
{
throw CreateWin32LastErrorException("Error creating file at path '{0}'.", path);
}
return(new System.IO.FileStream(hFile, System.IO.FileAccess.ReadWrite));
}
private static SafeFileHandle OpenReparsePoint(string reparsePoint, NativeMethods.EFileAccess accessMode)
{
// Open handle to reparse point.
SafeFileHandle reparsePointHandle = new SafeFileHandle(
NativeMethods.CreateFile(reparsePoint,
accessMode,
NativeMethods.EFileShare.Read | NativeMethods.EFileShare.Write | NativeMethods.EFileShare.Delete,
IntPtr.Zero,
NativeMethods.ECreationDisposition.OpenExisting,
NativeMethods.EFileAttributes.BackupSemantics | NativeMethods.EFileAttributes.OpenReparsePoint,
IntPtr.Zero),
true);
// Reparse point opened OK?
if (Marshal.GetLastWin32Error() != 0)
{
throw new Win32Exception("Unable to open reparse point.");
}
return(reparsePointHandle);
}
