FilesystemBasedFtpFile.java

/**
 * This file is part of Waarp Project.
 * 
 * Copyright 2009, Frederic Bregier, and individual contributors by the @author tags. See the
 * COPYRIGHT.txt in the distribution for a full listing of individual contributors.
 * 
 * All Waarp Project is free software: you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 * 
 * Waarp 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 General
 * Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License along with Waarp . If not, see
 * <http://www.gnu.org/licenses/>.
 */
package org.waarp.ftp.filesystembased;

import java.util.concurrent.locks.ReentrantLock;

import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;

import org.waarp.common.command.exception.CommandAbstractException;
import org.waarp.common.exception.FileEndOfTransferException;
import org.waarp.common.exception.FileTransferException;
import org.waarp.common.file.DataBlock;
import org.waarp.common.file.filesystembased.FilesystemBasedFileImpl;
import org.waarp.common.logging.WaarpLogger;
import org.waarp.common.logging.WaarpLoggerFactory;
import org.waarp.ftp.core.exception.FtpNoConnectionException;
import org.waarp.ftp.core.file.FtpFile;
import org.waarp.ftp.core.session.FtpSession;

/**
 * Filesystem implementation of a FtpFile
 * 
 * @author Frederic Bregier
 * 
 */
public abstract class FilesystemBasedFtpFile extends FilesystemBasedFileImpl implements FtpFile {
    /**
     * Internal Logger
     */
    private static final WaarpLogger logger = WaarpLoggerFactory
            .getLogger(FilesystemBasedFtpFile.class);

    /**
     * Retrieve lock to ensure only one call at a time for one file
     */
    private final ReentrantLock retrieveLock = new ReentrantLock();

    /**
     * @param session
     * @param dir
     *            It is not necessary the directory that owns this file.
     * @param path
     * @param append
     * @throws CommandAbstractException
     */
    public FilesystemBasedFtpFile(FtpSession session,
            FilesystemBasedFtpDir dir, String path, boolean append)
            throws CommandAbstractException {
        super(session, dir, path, append);
    }

    @Override
    public long length() throws CommandAbstractException {
        long length = super.length();
        if (((FtpSession) getSession()).getDataConn()
                .isFileStreamBlockAsciiImage()) {
            long block = (long) Math.ceil((double) length /
                    (double) getSession().getBlockSize());
            length += (block + 3) * 3;
        }
        return length;
    }

    /**
     * Launch retrieve operation (internal method, should not be called directly)
     * 
     */
    public void trueRetrieve() {
        retrieveLock.lock();
        try {
            if (!isReady) {
                return;
            }
            // First check if ready to run from Control
            try {
                ((FtpSession) session).getDataConn().getFtpTransferControl()
                        .waitForDataNetworkHandlerReady();
            } catch (InterruptedException e) {
                // bad thing
                logger.warn("DataNetworkHandler was not ready", e);
                return;
            }
            Channel channel = null;
            try {
                channel = ((FtpSession) session).getDataConn().getCurrentDataChannel();
            } catch (FtpNoConnectionException e) {
                if (this.isInReading()) {
                    logger.error("Should not be", e);
                    ((FtpSession) session).getDataConn().getFtpTransferControl()
                            .setTransferAbortedFromInternal(true);
                }
                logger.debug("Possible call while channel was on going to be closed once transfer was done", e);
                closeFile();
                ((FtpSession) session).getDataConn().getFtpTransferControl()
                        .setPreEndOfTransfer();
                return;
            }
            DataBlock block = null;
            try {
                block = readDataBlock();
            } catch (FileEndOfTransferException e) {
                // Last block (in fact, previous block was the last one,
                // but it could be aligned with the block size so not
                // detected)
                closeFile();
                ((FtpSession) session).getDataConn().getFtpTransferControl()
                        .setPreEndOfTransfer();
                return;
            }
            if (block == null) {
                // Last block (in fact, previous block was the last one,
                // but it could be aligned with the block size so not
                // detected)
                closeFile();
                ((FtpSession) session).getDataConn().getFtpTransferControl()
                        .setPreEndOfTransfer();
                return;
            }
            // While not last block
            ChannelFuture future = null;
            while (block != null && !block.isEOF()) {
                future = channel.writeAndFlush(block);
                try {
                    future.await();
                } catch (InterruptedException e) {
                }
                if (!future.isSuccess()) {
                    closeFile();
                    throw new FileTransferException("File transfer in error");
                }
                try {
                    block = readDataBlock();
                } catch (FileEndOfTransferException e) {
                    closeFile();
                    // Wait for last write
                    if (future.isSuccess()) {
                        ((FtpSession) session).getDataConn()
                                .getFtpTransferControl().setPreEndOfTransfer();
                    } else {
                        throw new FileTransferException("File transfer in error");
                    }
                    return;
                }
            }
            // Last block
            closeFile();
            if (block != null) {
                logger.debug("Write " + block.getByteCount());
                future = channel.writeAndFlush(block);
            }
            // Wait for last write
            if (future != null) {
                try {
                    future.await();
                } catch (InterruptedException e) {
                }
                if (future.isSuccess()) {
                    ((FtpSession) session).getDataConn().getFtpTransferControl()
                            .setPreEndOfTransfer();
                } else {
                    throw new FileTransferException("Write is not successful");
                }
            }
        } catch (FileTransferException e) {
            // An error occurs!
            ((FtpSession) session).getDataConn().getFtpTransferControl()
                    .setTransferAbortedFromInternal(true);
        } catch (CommandAbstractException e) {
            logger.error("Should not be", e);
            ((FtpSession) session).getDataConn().getFtpTransferControl()
                    .setTransferAbortedFromInternal(true);
        } finally {
            retrieveLock.unlock();
        }
    }
}