LineInputStream.java

/* This file is part of "MidpSSH".
 * Copyright (c) 2005 Karl von Randow.
 * 
 * --LICENSE NOTICE--
 * This program 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 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 * --LICENSE NOTICE--
 *
 */
package org.bbssh.io;

import java.io.IOException;
import java.io.InputStream;

/**
 * @author Karl
 *
 */
public class LineInputStream extends InputStream {

    private static final int BUFSIZ = 8192;
    
    private InputStream in;
    
    private byte[] buf = new byte[BUFSIZ];
    
    private int index = 0;
    
    public LineInputStream(InputStream in) {
        this.in = in;
    }
    
    public int read() throws IOException {
        return in.read();
    }
    
    public void close() throws IOException {
        in.close();
    }
    
    public String readLine(boolean includeEOL) throws IOException {
        while (true) {
            /* Read into buffer */
            int read;
            if (index < BUFSIZ) {
                read = in.read(buf, index, BUFSIZ - index);
                if (read > 0 ) {
                    index += read;
                }
            }
            else {
                read = -1;
            }
            
            /* Look for EOL */
            int eol = -1;
            int next = -1;
            
            for (int i = 0; i < index; i++) {
                if (buf[i] == '\r') {
                    if (i + 1 < index && buf[i+1] == '\n') {
                        eol = i;
                        next = i + 2;
                    }
                    else {
                        eol = i;
                        next = i + 1;
                    }
                    break;
                }
                else if (buf[i] == '\n') {
                    eol = i;
                    next = i + 1;
                    break;
                }
            }
           
            if (eol != -1) {
				String str;
				if (includeEOL) {
					str = new String(buf, 0, eol + 1);
				} else {
					str = new String(buf, 0, eol);
				}
                
                index = index - next;
                System.arraycopy(buf, next, buf, 0, index);
                return str;
            }
            else if (read == -1) {
                /* EOF */
                if (index > 0) {
                    String str = new String(buf, 0, index);
                    index = 0;
                    return str;
                }
                else {
                    return null;
                }
            }
        }
    }

}