internal static byte[] GetDacl(string filename)
{
int lengthNeeded = 0;
int num2 = UnsafeNativeMethods.GetFileSecurity(filename, 7, null, 0, ref lengthNeeded);
int lastError = Marshal.GetLastWin32Error();
if (num2 != 0)
{
return(s_nullDacl);
}
if (HttpException.HResultFromLastError(lastError) != -2147024774)
{
return(null);
}
byte[] securityDescriptor = new byte[lengthNeeded];
if (UnsafeNativeMethods.GetFileSecurity(filename, 7, securityDescriptor, securityDescriptor.Length, ref lengthNeeded) == 0)
{
return(null);
}
byte[] buffer2 = (byte[])s_interned[securityDescriptor];
if (buffer2 == null)
{
lock (s_interned.SyncRoot)
{
buffer2 = (byte[])s_interned[securityDescriptor];
if (buffer2 == null)
{
buffer2 = securityDescriptor;
s_interned[buffer2] = buffer2;
}
}
}
return(buffer2);
}