/*
* $Id$
*
* Copyright (C) 2003-2015 JNode.org
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; If not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
package org.jnode.fs.exfat;
import java.io.IOException;
/**
* @author Matthias Treydte <waldheinz at gmail.com>
*/
final class Cluster {
/**
* Marks a cluster containing a bad block.
*/
private static final long BAD = 0xfffffff7l;
/**
* Marks the final cluster of a file or directory.
*/
private static final long END = 0xffffffffl;
/**
* The first data cluster that can be used on exFAT file systems.
*/
public static final long FIRST_DATA_CLUSTER = 2;
/**
* The size of an exFAT cluster in blocks.
*/
public static final int SIZE = 4;
public static boolean invalid(long cluster) {
return ((cluster == END) || (cluster == BAD));
}
public static void checkValid(long cluster) throws IOException {
if (cluster < FIRST_DATA_CLUSTER || invalid(cluster)) {
throw new IOException("bad cluster number " + cluster);
}
}
public static void checkValid(
long cluster, ExFatSuperBlock sblk) throws IOException {
checkValid(cluster);
final long maxCluster = sblk.getClusterCount() + 1;
if (cluster > maxCluster) {
final StringBuilder sb = new StringBuilder();
sb.append("cluster ").append(cluster);
sb.append(" exceeds maximum of ").append(maxCluster);
throw new IOException(sb.toString());
}
}
private Cluster() {
/* utility class, no instances */
}
}