/*
* Copyright (C) 2012 Brendan Robert (BLuRry) brendan.robert@gmail.com.
*
* 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 jace.hardware.massStorage;
import java.io.IOException;
/**
* Maintain freespace and node allocation
*
* @author Brendan Robert (BLuRry) brendan.robert@gmail.com
*/
public class FreespaceBitmap extends DiskNode {
int size = (ProdosVirtualDisk.MAX_BLOCK + 1) / 8 / ProdosVirtualDisk.BLOCK_SIZE;
public FreespaceBitmap(ProdosVirtualDisk fs, int start) throws IOException {
super(fs, start);
allocate();
}
@Override
public void doDeallocate() {
//
}
@Override
public void doAllocate() throws IOException {
for (int i = 1; i < size; i++) {
SubNode subNode = new SubNode(i, this, getBaseBlock());
}
}
@Override
public void doRefresh() {
//
}
@Override
public void readBlock(int sequence, byte[] buffer) throws IOException {
int startBlock = sequence * ProdosVirtualDisk.BLOCK_SIZE * 8;
int endBlock = (sequence + 1) * ProdosVirtualDisk.BLOCK_SIZE * 8;
for (int i = startBlock; i < endBlock; i++) {
if (!getOwnerFilesystem().isBlockAllocated(i)) {
int pos = (i - startBlock) / 8;
int bit = 1 << (i % 8);
buffer[pos] |= bit;
}
}
}
@Override
public int getLength() {
return (1 + getChildren().size()) * IDisk.BLOCK_SIZE;
}
}