<match value="\nReceived: from " type="string" offset="32:256"/>
        <match value="\nMime-Version: " type="string" offset="32:256"/>

        <match value="\nX-" type="stringignorecase" offset="32:256">
          <match value="\nFrom: " type="string" offset="32:8192"/>
          <match value="\nDate: " type="string" offset="32:8192"/>
          <match value="\nSubject: " type="string" offset="32:8192"/>

// is a list of ranges with an accompanying value. Given a matching range r,
// the value for b is by r.value + (b - r.lo) * stride.
func (t *sparseBlocks) lookup(n uint32, b byte) uint16 {
	offset := t.offset[n]
	header := t.values[offset]
	lo := offset + 1
	hi := lo + uint16(header.lo)
	for lo < hi {
		m := lo + (hi-lo)/2
		r := t.values[m]
		if r.lo <= b && b <= r.hi {
			return r.value + uint16(b-r.lo)*header.value
		}

                throw throwAsUncheckedException(e);
            }
        }
        if (offset == -1) {
            offset = encoder.getWritePosition();
            if (offset == Integer.MAX_VALUE) {
                throw new IllegalStateException("Unable to write to binary store. "
                        + "The bytes offset has reached a point where using it is unsafe. Please report this error.");
            }
        }

                return i;
            }
        }
        return absolutePath.length();
    }

    private VfsRelativePath(String absolutePath, int offset) {
        this.absolutePath = absolutePath;
        this.offset = offset;
    }

    /**
     * Returns a new relative path starting from the child.
     *
     * E.g.
     *   (some/path, some) -> path

}

// idnaIndex: 36 blocks, 2304 entries, 4608 bytes
// Block 0 is the zero block.
var idnaIndex = [2304]uint16{
	// Block 0x0, offset 0x0
	// Block 0x1, offset 0x40
	// Block 0x2, offset 0x80
	// Block 0x3, offset 0xc0
	0xc2: 0x01, 0xc3: 0x7d, 0xc4: 0x02, 0xc5: 0x03, 0xc6: 0x04, 0xc7: 0x05,
	0xc8: 0x06, 0xc9: 0x7e, 0xca: 0x7f, 0xcb: 0x07, 0xcc: 0x80, 0xcd: 0x08, 0xce: 0x09, 0xcf: 0x0a,

    private final int offset;
    private final int length;

    public DefaultOffsetInFileLocation(String path, int offset, int length) {
        super(path);
        this.offset = offset;
        this.length = length;
    }

    @Override
    public int getOffset() {
        return offset;
    }

    @Override
    public int getLength() {

	var newOffset int64
	switch whence {
	case io.SeekStart:
		newOffset = offset
	case io.SeekCurrent:
		newOffset = r.offset + offset
	case io.SeekEnd:
		newOffset = r.size + offset
	default:
		return 0, os.ErrInvalid
	}

	switch {
	case newOffset == r.offset:
		return newOffset, nil

	case newOffset < 0, newOffset > r.size:
		return 0, os.ErrInvalid

//sys	utimes(path string, times *[2]Timeval) (err error)

func Fadvise(fd int, offset int64, length int64, advice int) (err error) {
	_, _, e1 := Syscall6(SYS_FADVISE64_64, uintptr(fd), uintptr(advice), uintptr(offset>>32), uintptr(offset), uintptr(length>>32), uintptr(length))
	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}

func seek(fd int, offset int64, whence int) (int64, syscall.Errno) {
	var newoffset int64

    private final int offset;
    private final int length;

    private DefaultOffsetInFileLocation(String path, int offset, int length) {
        super(path);
        this.offset = offset;
        this.length = length;
    }

    public static FileLocation from(String path, int offset, int length) {
        return new DefaultOffsetInFileLocation(path, offset, length);
    }


    @Override

	if offset < 0 || offset >= r.max {
		return false, fmt.Errorf("offset %d out of range [0,%d]", offset, r.max)
	}
	if r.allocated.Bit(offset) == 1 {
		return false, nil
	}
	r.allocated = r.allocated.SetBit(r.allocated, offset, 1)
	r.count++
	return true, nil
}

// AllocateNext reserves one of the items from the pool.
// (0, false, nil) may be returned if there are no items left.