/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.jackrabbit.oak.plugins.segment.standby.codec;
import static org.apache.jackrabbit.oak.plugins.segment.standby.codec.SegmentEncoder.EXTRA_HEADERS_LEN;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.LengthFieldBasedFrameDecoder;
import java.nio.ByteBuffer;
import java.util.UUID;
import org.apache.jackrabbit.oak.plugins.segment.Segment;
import org.apache.jackrabbit.oak.plugins.segment.SegmentId;
import org.apache.jackrabbit.oak.plugins.segment.SegmentStore;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.hash.Hasher;
import com.google.common.hash.Hashing;
public class SegmentDecoder extends LengthFieldBasedFrameDecoder {
private static final Logger log = LoggerFactory
.getLogger(SegmentDecoder.class);
/**
* the maximum possible size a header message might have
*/
private static final int MAX_LENGHT = Segment.MAX_SEGMENT_SIZE
+ EXTRA_HEADERS_LEN;
private final SegmentStore store;
public SegmentDecoder(SegmentStore store) {
super(MAX_LENGHT, 0, 4, 0, 0);
this.store = store;
}
@Override
protected Object decode(ChannelHandlerContext ctx, ByteBuf in)
throws Exception {
ByteBuf frame = (ByteBuf) super.decode(ctx, in);
if (frame == null) {
return null;
}
int len = frame.readInt();
byte type = frame.readByte();
long msb = frame.readLong();
long lsb = frame.readLong();
long hash = frame.readLong();
byte[] segment = new byte[len - 25];
frame.getBytes(29, segment);
Hasher hasher = Hashing.murmur3_32().newHasher();
long check = hasher.putBytes(segment).hash().padToLong();
if (hash == check) {
SegmentId id = new SegmentId(store.getTracker(), msb, lsb);
Segment s = new Segment(store.getTracker(), id,
ByteBuffer.wrap(segment));
log.debug("received type {} with id {} and size {}", type, id,
s.size());
return s;
}
log.debug("received corrupted segment {}, ignoring", new UUID(msb, lsb));
return null;
}
@Override
protected ByteBuf extractFrame(ChannelHandlerContext ctx, ByteBuf buffer,
int index, int length) {
return buffer.slice(index, length);
}
}