RAMFSPlugin.java

/*
 * $Id$
 *
 * 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.ramfs.def;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;

import javax.naming.NameNotFoundException;

import org.apache.log4j.Logger;
import org.jnode.driver.DeviceAlreadyRegisteredException;
import org.jnode.driver.DeviceException;
import org.jnode.driver.DeviceManager;
import org.jnode.driver.DeviceNotFoundException;
import org.jnode.driver.DeviceUtils;
import org.jnode.driver.DriverException;
import org.jnode.driver.virtual.VirtualDevice;
import org.jnode.driver.virtual.VirtualDeviceFactory;
import org.jnode.fs.FSDirectory;
import org.jnode.fs.FSFile;
import org.jnode.fs.FileSystemException;
import org.jnode.fs.ramfs.RAMFileSystem;
import org.jnode.fs.ramfs.RAMFileSystemType;
import org.jnode.fs.service.FileSystemService;
import org.jnode.naming.InitialNaming;
import org.jnode.plugin.Plugin;
import org.jnode.plugin.PluginDescriptor;
import org.jnode.plugin.PluginException;

/**
 * This plugin creates a new Ram filesystem and mounts it to /jnode/
 * 
 * @author peda
 */
public class RAMFSPlugin extends Plugin {
    /** RAMFS logger */
    private static final Logger log = Logger.getLogger(RAMFSPlugin.class);

    /**
     * @param descriptor
     */
    public RAMFSPlugin(PluginDescriptor descriptor) {
        super(descriptor);
        log.debug("RAMFSPlugin created.");
    }

    @Override
    protected void startPlugin() throws PluginException {
        log.info("start ramfs");
        try {
            FileSystemService fSS = InitialNaming.lookup(FileSystemService.NAME);
            RAMFileSystemType type = fSS.getFileSystemType(RAMFileSystemType.ID);

            try {
                VirtualDevice dev =
                        VirtualDeviceFactory.createDevice(RAMFileSystemType.VIRTUAL_DEVICE_NAME);
                log.info(dev.getId() + " registered");

                final RAMFileSystem fs = type.create(dev, true);
                fSS.registerFileSystem(fs);

                final String mountPath = "jnode";
                fSS.mount(mountPath, fs, null);
                log.info("Mounted " + type.getName() + " on " + mountPath);

                FSDirectory root_dir = fs.getRootEntry().getDirectory();
                root_dir.addDirectory("home");
                root_dir.addDirectory("tmp");
                // adding files to /jnode/lib/ required by thecore classes
                FSDirectory libDir = (FSDirectory) root_dir.addDirectory("lib");
                InputStream is = RAMFSPlugin.class.getResourceAsStream("flavormap.properties");
                if (is != null) {
                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    byte[] buf = new byte[1024];
                    int c;
                    while ((c = is.read(buf)) > -1)
                        baos.write(buf, 0, c);

                    is.close();
                    baos.flush();
                    baos.close();

                    ByteBuffer data = ByteBuffer.wrap(baos.toByteArray());
                    FSFile fmp = (FSFile) libDir.addFile("flavormap.properties");
                    fmp.write(0, data);
                    fmp.flush();
                }
            } catch (DeviceAlreadyRegisteredException ex) {
                log.error("RAMFS is allready running.");
            } catch (FileSystemException ex) {
                log.error("Cannot mount " + type.getName() + " filesystem ", ex);
            } catch (DeviceException ex) {
                log.debug("DeviceExeption.", ex);
            } catch (IOException ex) {
                log.error("Cannot mount RAMFS", ex);
            }
        } catch (NameNotFoundException e) {
            log.error("Filsystemservice not found");
        } catch (FileSystemException e) {
            log.error("Filesystemtype not found");
        }
    }

    @Override
    protected void stopPlugin() throws PluginException {
        log.info("stop RAMFS");
        try {
            FileSystemService fSS = InitialNaming.lookup(FileSystemService.NAME);
            final DeviceManager dm = DeviceUtils.getDeviceManager();
            VirtualDevice dev = (VirtualDevice) dm.getDevice(RAMFileSystemType.VIRTUAL_DEVICE_NAME);
            fSS.unregisterFileSystem(dev);
            log.info("RAMFS unmounted");
            dm.unregister(dev);
            log.info("RAMFS unregistered");
        } catch (NameNotFoundException e) {
            log.error("filsystemservice / filesystemtype not found");
        } catch (DeviceNotFoundException ex) {
            log.info("no ramfs present");
        } catch (DriverException ex) {
            log.error(ex);
        }
    }
}