private void add(long offset, long length, byte b) //called on different thread to IsScrubbed
{
//round to the nearest block start
if (offset % 0x7c00L != 0)
{
length += offset % 0x7c00L;
offset -= offset % 0x7c00L;
}
if (length % 0x7c00L != 0)
{
length += 0x7c00L - (length % 0x7c00L); //pad to block end
}
offset = (long)(offset / 0x7c00L) * 0x8000L;
length = (long)(length / 0x7c00L) * 0x8000L;
if (_last != null && _last.Byte == b && offset >= _last.Offset && offset <= _last.Offset + _last.Length) //extend
{
if (offset + length > _last.Offset + _last.Length)
{
_last.Length = (offset + length) - _last.Offset;
}
}
else
{
_last = new ScrubRegion()
{
Offset = offset, Length = length, Byte = b
};
lock (_scrub)
_scrub.Enqueue(_last);
_cache.Add(_last);
}
}
private bool isBlockScrubbed(ScrubRegion region, long offset, out byte scrubByte)
{
scrubByte = 0;
if (region != null)
{
if ((offset >= region.Offset && offset < region.Offset + region.Length))
{
scrubByte = region.Byte;
return(true);
}
}
return(false);
}
public bool IsBlockScrubbedScanMode(long offset, out byte scrubByte)
{
if (_next == null || _next.Offset + _next.Length < offset)
{
lock (_scrub)
{
if (_scrub.Count != 0)
{
_next = _scrub.Dequeue();
}
else
{
_next = null;
}
}
}
return(isBlockScrubbed(_next, offset, out scrubByte));
}
