/*
* $Id$
*
* Copyright (C) 2003-2014 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.hfs;
import java.io.IOException;
import java.nio.ByteBuffer;
import org.jnode.driver.ApiNotFoundException;
import org.jnode.driver.Device;
import org.jnode.driver.block.BlockDeviceAPI;
import org.jnode.driver.block.FSBlockDeviceAPI;
import org.jnode.driver.block.MappedBlockDeviceSupport;
import org.jnode.fs.BlockDeviceFileSystemType;
import org.jnode.fs.FileSystemException;
import org.jnode.fs.hfsplus.HfsPlusFileSystem;
import org.jnode.partitions.PartitionTableEntry;
/**
* A HFS wrapper around HFS+.
*
* @author Luke Quinane
*/
public class HfsWrapperFileSystemType implements BlockDeviceFileSystemType<HfsPlusFileSystem> {
public static final Class<HfsWrapperFileSystemType> ID = HfsWrapperFileSystemType.class;
@Override
public final HfsPlusFileSystem create(final Device device, final boolean readOnly) throws FileSystemException {
ByteBuffer mdbData = ByteBuffer.allocate(MasterDirectoryBlock.LENGTH);
try {
device.getAPI(BlockDeviceAPI.class).read(0x400, mdbData);
} catch (ApiNotFoundException e) {
throw new FileSystemException("Failed to find the block device API", e);
} catch (IOException e) {
throw new FileSystemException("Error reading HFS wrapper MDB", e);
}
MasterDirectoryBlock mdb = new MasterDirectoryBlock(mdbData.array());
// Calculate the offset and length of the embedded HFS+ file system
long offset = mdb.getAllocationBlockStart() * 512 +
mdb.getEmbeddedVolumeStartBlock() * mdb.getAllocationBlockSize();
long length = mdb.getEmbeddedVolumeBlockCount() * mdb.getAllocationBlockSize();
MappedBlockDeviceSupport subDevice;
try {
// Take a sub-section of the device to pass down to the HFS+ code
subDevice = new MappedBlockDeviceSupport(device, offset, length);
} catch (IOException e) {
throw new FileSystemException("Error creating sub-device for HFS+", e);
}
HfsPlusFileSystem fs = new HfsPlusFileSystem(subDevice, readOnly, this);
fs.read();
return fs;
}
@Override
public final String getName() {
return "HFS Wrapper";
}
@Override
public final boolean supports(final PartitionTableEntry pte, final byte[] firstSector,
final FSBlockDeviceAPI devApi) {
byte[] mdbData = new byte[MasterDirectoryBlock.LENGTH];
System.arraycopy(firstSector, 0x400, mdbData, 0, mdbData.length);
MasterDirectoryBlock mdb = new MasterDirectoryBlock(mdbData);
return
mdb.getSignature() == MasterDirectoryBlock.HFS_MDB_SIGNATURE &&
mdb.getEmbeddedSignature() == MasterDirectoryBlock.HFSPLUS_EMBEDDED_SIGNATURE;
}
}