jazmin.server.relay.udp.webrtc.NettyUdpTransport.java Source code

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Here is the source code for jazmin.server.relay.udp.webrtc.NettyUdpTransport.java

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package jazmin.server.relay.udp.webrtc;
/*
 * TeleStax, Open Source Cloud Communications
 * Copyright 2011-2014, Telestax Inc and individual contributors
 * by the @authors tag.
 *
 * This program is free software: you can redistribute it and/or modify
 * under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation; either version 3 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 *
 */

import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.socket.DatagramPacket;

import java.io.IOException;
import java.net.InetSocketAddress;

import org.bouncycastle.crypto.tls.DatagramTransport;

/**
 * Datagram Transport implementation that uses NIO instead of bocking IO.
 * 
 * @author Henrique Rosa
 * 
 */
public class NettyUdpTransport implements DatagramTransport {

    public static final int DEFAULT_MTU = 1500;
    private final static int MIN_IP_OVERHEAD = 20;
    private final static int MAX_IP_OVERHEAD = MIN_IP_OVERHEAD + 64;
    private final static int UDP_OVERHEAD = 8;
    public final static int MAX_DELAY = 4000;

    private int mtu;
    private final int receiveLimit;
    private final int sendLimit;
    private long startTime;
    ByteArrayBlockingQueue queue;
    Channel udpChannel;
    private InetSocketAddress remoteAddress;

    //
    public void write(byte[] data) throws Exception {
        queue.put(data);
    }

    public NettyUdpTransport() {
        mtu = 1400;
        queue = new ByteArrayBlockingQueue(3000);
        this.receiveLimit = Math.max(0, mtu - MIN_IP_OVERHEAD - UDP_OVERHEAD);
        this.sendLimit = Math.max(0, mtu - MAX_IP_OVERHEAD - UDP_OVERHEAD);
        this.startTime = System.currentTimeMillis();
    }

    //
    public void startHandshake() {
        startTime = System.currentTimeMillis();
    }

    @Override
    public int getReceiveLimit() throws IOException {
        return this.receiveLimit;
    }

    @Override
    public int getSendLimit() throws IOException {
        return this.sendLimit;
    }

    @Override
    public int receive(byte[] buf, int off, int len, int waitMillis) throws IOException {
        if (this.hasTimeout()) {
            throw new IllegalStateException("Handshake is taking too long! (>" + MAX_DELAY + "ms");
        }
        System.err.println("receive:" + off + "/" + len + "/" + waitMillis + "/" + queue.count);
        int readSize = Math.min(len, queue.count);
        byte bb[] = new byte[readSize];
        try {
            Thread.sleep(1000);
            queue.take(bb);
        } catch (InterruptedException e) {
            throw new IOException(e);
        }
        System.arraycopy(bb, 0, buf, off, bb.length);
        System.err.println(
                "receive:" + off + "/" + len + "/" + waitMillis + "/" + queue.count + "/>>>>>>>" + readSize);
        return readSize;
    }

    @Override
    public void send(byte[] buf, int off, int len) throws IOException {
        System.err.println("send:" + off + "/" + len);
        if (len > getSendLimit()) {
        }
        if (this.hasTimeout()) {
            throw new IllegalStateException("Handshake is taking too long! (>" + MAX_DELAY + "ms");
        }
        DatagramPacket dp = new DatagramPacket(Unpooled.wrappedBuffer(buf, off, len), remoteAddress);
        udpChannel.writeAndFlush(dp);
    }

    @Override
    public void close() throws IOException {
        System.err.println("close");
    }

    private boolean hasTimeout() {
        return (System.currentTimeMillis() - this.startTime) > MAX_DELAY;
    }

}