/*
 * $Id$
 *
 * 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.driver.block;

import java.io.IOException;

/**
 * <description>
 */
public class BlockDeviceAPIHelper {

    /**
     * check if devOffset is within the bounds of the given BlockDevice
     *
     * @param api
     * @param devOffset
     * @throws IOException
     */
    public static void checkBounds(BlockDeviceAPI api, long devOffset) throws IOException {
        if (devOffset < 0)
            throw new IOException("devOffset < 0");

        if (devOffset >= api.getLength())
            throw new IOException("devOffset (" + devOffset + ") > upper bound (" + api.getLength() + ")");
    }

    /**
     * check if devOffset up to devOffset+length is within the bounds of the given BlockDevice
     *
     * @param api
     * @param devOffset
     * @param length
     * @throws IOException
     */
    public static void checkBounds(BlockDeviceAPI api, long devOffset, long length) throws IOException {

        checkBounds(api, devOffset);

        if (length <= 0)
            throw new IOException("length <= 0");

        checkBounds(api, devOffset + length - 1); // don't forget to substract 1 !
    }

    /**
     * check if devOffset is sectorSize alligned
     *
     * @param sectorSize
     * @param api
     * @param devOffset
     * @param length
     * @throws IOException
     */
    public static void checkAlignment(int sectorSize, BlockDeviceAPI api, long devOffset, int length)
        throws IOException {

        if ((devOffset % sectorSize) != 0) {
            throw new IOException(
                "Non aligned devOffset not allowed. Size requested = " + devOffset + " Sector size = " + sectorSize);
        }
        if ((length % sectorSize) != 0) {
            throw new IOException(
                "Non aligned length not allowed. Size requested = " + length + " Sector size = " + sectorSize);
        }
    }
}