/*
* Copyright 2016 Anton Tananaev (anton@traccar.org)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.traccar.protocol;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.frame.FrameDecoder;
import org.traccar.helper.StringFinder;
public class GranitFrameDecoder extends FrameDecoder {
@Override
protected Object decode(
ChannelHandlerContext ctx, Channel channel, ChannelBuffer buf) throws Exception {
int indexEnd = buf.indexOf(buf.readerIndex(), buf.writerIndex(), new StringFinder("\r\n"));
if (indexEnd != -1) {
int indexTilde = buf.indexOf(buf.readerIndex(), buf.writerIndex(), new StringFinder("~"));
if (indexTilde != -1 && indexTilde < indexEnd) {
int length = buf.getUnsignedShort(indexTilde + 1);
indexEnd = buf.indexOf(indexTilde + 2 + length, buf.writerIndex(), new StringFinder("\r\n"));
if (indexEnd == -1) {
return null;
}
}
ChannelBuffer frame = buf.readBytes(indexEnd - buf.readerIndex());
buf.skipBytes(2);
return frame;
}
return null;
}
}