public override void Read(uint offset, uint length, IntPtr dest, ref uint bytesRead)
{
//DebugLogger.WriteLine("Conditional {2} reading from OS {0} L {1}", offset, length, Name);
bool header = (offset < 24);
bool init = (offset == 24);
if ((!_lastHeader && header) || (init && !_lastInit)) //re-evaluate
{
_current = null;
if (!_handle.Equals(IntPtr.Zero))
{
Win32.CloseHandle(_handle);
}
_handle = IntPtr.Zero;
foreach (var of in _files)
{
if (of.CFolder == null || of.CFolder.IsActive(of.CName))
{
DebugLogger.WriteLine($"Conditional {Name} switching to {of.File}");
_current = of;
Bytes.WriteInt(_header, 20, of.Size);
break;
}
}
if (_current == null)
{
DebugLogger.WriteLine($"Conditional {Name} switching to fallback");
}
_lastInit = true; //we're ready to read file headers
}
else
{
_lastInit = init;
}
if (_current != null && _handle.Equals(IntPtr.Zero) && _current.Archive == null)
{
_handle = Wrap.CreateFileW(_current.File, System.IO.FileAccess.Read, System.IO.FileShare.Read, IntPtr.Zero, System.IO.FileMode.Open, System.IO.FileAttributes.Normal, IntPtr.Zero);
}
_lastHeader = header;
_access = DateTime.Now;
if (_current == null) //read from fallback
//DebugLogger.WriteLine("Conditional reading from fallback handle {0} with extra offset {1}", _fallbackHandle, _fallbackOffset);
{
Win32.OVERLAPPED ov = new Win32.OVERLAPPED()
{
EventHandle = IntPtr.Zero,
Internal = UIntPtr.Zero,
InternalHigh = UIntPtr.Zero,
Offset = _fallbackOffset + offset,
OffsetHigh = 0
};
Win32.ReadFile(_fallbackHandle, dest, length, ref bytesRead, ref ov);
//DebugLogger.WriteLine("Conditional {1} reading from fallback - {0} bytes read", bytesRead, Name);
}
else
{
if (offset < 24)
{
length = Math.Min(length, 24 - offset);
System.Runtime.InteropServices.Marshal.Copy(_header, (int)offset, dest, (int)length);
bytesRead = length;
//DebugLogger.WriteLine("Conditional {2} reading from cheader - {0} bytes read [current size is {1}]", bytesRead, BitConverter.ToInt32(_header, 20), Name);
return;
}
else
{
offset -= 24;
if (_current.Archive == null)
{
Wrap.SetFilePointer(_handle, (int)offset, IntPtr.Zero, Wrap.EMoveMethod.Begin);
Win32.ReadFile(_handle, dest, length, ref bytesRead, IntPtr.Zero);
//DebugLogger.WriteLine("Conditional {1} reading from cfile - {0} bytes read", bytesRead, Name);
}
else
{
_current.Archive.RawRead(_current.File, offset, length, dest, ref bytesRead);
//DebugLogger.WriteLine("Conditional {1} reading from cfile archive offset {2} length {3} - {0} bytes read", bytesRead, Name, offset, length);
}
}
}
}
