Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 1 | /** |
Ray Milkey | 269ffb9 | 2014-04-03 14:43:30 -0700 | [diff] [blame] | 2 | * Copyright 2011, Big Switch Networks, Inc. |
| 3 | * Originally created by David Erickson, Stanford University |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| 6 | * not use this file except in compliance with the License. You may obtain |
| 7 | * a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| 13 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 14 | * License for the specific language governing permissions and limitations |
| 15 | * under the License. |
| 16 | **/ |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 17 | |
| 18 | package net.floodlightcontroller.core.internal; |
| 19 | |
| 20 | import java.util.List; |
| 21 | |
| 22 | import org.jboss.netty.buffer.ChannelBuffer; |
| 23 | import org.jboss.netty.channel.Channel; |
| 24 | import org.jboss.netty.channel.ChannelHandlerContext; |
| 25 | import org.jboss.netty.handler.codec.frame.FrameDecoder; |
Brian O'Connor | c67f9fa | 2014-08-07 18:17:46 -0700 | [diff] [blame] | 26 | import org.projectfloodlight.openflow.protocol.OFFactories; |
| 27 | import org.projectfloodlight.openflow.protocol.OFMessage; |
| 28 | import org.projectfloodlight.openflow.protocol.OFMessageReader; |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 29 | |
| 30 | /** |
Brian O'Connor | c67f9fa | 2014-08-07 18:17:46 -0700 | [diff] [blame] | 31 | * Decode an openflow message from a Channel, for use in a netty pipeline |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 32 | */ |
| 33 | public class OFMessageDecoder extends FrameDecoder { |
| 34 | |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 35 | @Override |
| 36 | protected Object decode(ChannelHandlerContext ctx, Channel channel, |
| 37 | ChannelBuffer buffer) throws Exception { |
| 38 | if (!channel.isConnected()) { |
| 39 | // In testing, I see decode being called AFTER decode last. |
Brian O'Connor | c67f9fa | 2014-08-07 18:17:46 -0700 | [diff] [blame] | 40 | // This check avoids that from reading corrupted frames |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 41 | return null; |
| 42 | } |
| 43 | |
Brian O'Connor | c67f9fa | 2014-08-07 18:17:46 -0700 | [diff] [blame] | 44 | // Note that a single call to decode results in reading a single |
| 45 | // OFMessage from the channel buffer, which is passed on to, and processed |
| 46 | // by, the controller (in OFChannelHandler). |
| 47 | // This is different from earlier behavior (with the original openflowj), |
| 48 | // where we parsed all the messages in the buffer, before passing on |
| 49 | // a list of the parsed messages to the controller. |
| 50 | // The performance *may or may not* not be as good as before. |
| 51 | OFMessageReader<OFMessage> reader = OFFactories.getGenericReader(); |
| 52 | OFMessage message = reader.readFrom(buffer); |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 53 | |
Brian O'Connor | c67f9fa | 2014-08-07 18:17:46 -0700 | [diff] [blame] | 54 | return message; |
Umesh Krishnaswamy | 345ee99 | 2012-12-13 20:29:48 -0800 | [diff] [blame] | 55 | } |
| 56 | |
| 57 | } |