/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file to you 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 io.netty.handler.codec.sctp;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandler;
import io.netty.channel.sctp.SctpMessage;
import io.netty.handler.codec.MessageToMessageDecoder;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* {@link MessageToMessageDecoder} which will take care of handle fragmented {@link SctpMessage}s, so
* only <strong>complete</strong> {@link SctpMessage}s will be forwarded to the next
* {@link ChannelInboundHandler}.
*/
public class SctpMessageCompletionHandler extends MessageToMessageDecoder<SctpMessage> {
private final Map<Integer, ByteBuf> fragments = new HashMap<Integer, ByteBuf>();
@Override
protected void decode(ChannelHandlerContext ctx, SctpMessage msg, List<Object> out) throws Exception {
final ByteBuf byteBuf = msg.content();
final int protocolIdentifier = msg.protocolIdentifier();
final int streamIdentifier = msg.streamIdentifier();
final boolean isComplete = msg.isComplete();
ByteBuf frag;
if (fragments.containsKey(streamIdentifier)) {
frag = fragments.remove(streamIdentifier);
} else {
frag = Unpooled.EMPTY_BUFFER;
}
if (isComplete && !frag.isReadable()) {
//data chunk is not fragmented
out.add(msg);
} else if (!isComplete && frag.isReadable()) {
//more message to complete
fragments.put(streamIdentifier, Unpooled.wrappedBuffer(frag, byteBuf));
} else if (isComplete && frag.isReadable()) {
//last message to complete
fragments.remove(streamIdentifier);
SctpMessage assembledMsg = new SctpMessage(
protocolIdentifier,
streamIdentifier,
Unpooled.wrappedBuffer(frag, byteBuf));
out.add(assembledMsg);
} else {
//first incomplete message
fragments.put(streamIdentifier, byteBuf);
}
byteBuf.retain();
}
}