| /** |
| * 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.hadoop.hdfs.protocol.datatransfer; |
| |
| import static org.apache.hadoop.hdfs.protocolPB.PBHelperClient.vintPrefixed; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.util.ArrayList; |
| |
| import com.google.common.collect.Lists; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.PipelineAckProto; |
| import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status; |
| import com.google.protobuf.TextFormat; |
| import org.apache.hadoop.hdfs.util.LongBitFormat; |
| |
| /** Pipeline Acknowledgment **/ |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public class PipelineAck { |
| PipelineAckProto proto; |
| public final static long UNKOWN_SEQNO = -2; |
| final static int OOB_START = Status.OOB_RESTART_VALUE; // the first OOB type |
| final static int OOB_END = Status.OOB_RESERVED3_VALUE; // the last OOB type |
| |
| public enum ECN { |
| DISABLED(0), |
| SUPPORTED(1), |
| SUPPORTED2(2), |
| CONGESTED(3); |
| |
| private final int value; |
| private static final ECN[] VALUES = values(); |
| static ECN valueOf(int value) { |
| return VALUES[value]; |
| } |
| |
| ECN(int value) { |
| this.value = value; |
| } |
| |
| public int getValue() { |
| return value; |
| } |
| } |
| |
| private enum StatusFormat { |
| STATUS(null, 4), |
| RESERVED(STATUS.BITS, 1), |
| ECN_BITS(RESERVED.BITS, 2); |
| |
| private final LongBitFormat BITS; |
| |
| StatusFormat(LongBitFormat prev, int bits) { |
| BITS = new LongBitFormat(name(), prev, bits, 0); |
| } |
| |
| static Status getStatus(int header) { |
| return Status.valueOf((int) STATUS.BITS.retrieve(header)); |
| } |
| |
| static ECN getECN(int header) { |
| return ECN.valueOf((int) ECN_BITS.BITS.retrieve(header)); |
| } |
| |
| public static int setStatus(int old, Status status) { |
| return (int) STATUS.BITS.combine(status.getNumber(), old); |
| } |
| |
| public static int setECN(int old, ECN ecn) { |
| return (int) ECN_BITS.BITS.combine(ecn.getValue(), old); |
| } |
| } |
| |
| /** default constructor **/ |
| public PipelineAck() { |
| } |
| |
| /** |
| * Constructor assuming no next DN in pipeline |
| * @param seqno sequence number |
| * @param replies an array of replies |
| */ |
| public PipelineAck(long seqno, int[] replies) { |
| this(seqno, replies, 0L); |
| } |
| |
| /** |
| * Constructor |
| * @param seqno sequence number |
| * @param replies an array of replies |
| * @param downstreamAckTimeNanos ack RTT in nanoseconds, 0 if no next DN in pipeline |
| */ |
| public PipelineAck(long seqno, int[] replies, |
| long downstreamAckTimeNanos) { |
| ArrayList<Status> statusList = Lists.newArrayList(); |
| ArrayList<Integer> flagList = Lists.newArrayList(); |
| for (int r : replies) { |
| statusList.add(StatusFormat.getStatus(r)); |
| flagList.add(r); |
| } |
| proto = PipelineAckProto.newBuilder() |
| .setSeqno(seqno) |
| .addAllReply(statusList) |
| .addAllFlag(flagList) |
| .setDownstreamAckTimeNanos(downstreamAckTimeNanos) |
| .build(); |
| } |
| |
| /** |
| * Get the sequence number |
| * @return the sequence number |
| */ |
| public long getSeqno() { |
| return proto.getSeqno(); |
| } |
| |
| /** |
| * Get the number of replies |
| * @return the number of replies |
| */ |
| public short getNumOfReplies() { |
| return (short)proto.getReplyCount(); |
| } |
| |
| /** |
| * get the header flag of ith reply |
| */ |
| public int getHeaderFlag(int i) { |
| if (proto.getFlagCount() > 0) { |
| return proto.getFlag(i); |
| } else { |
| return combineHeader(ECN.DISABLED, proto.getReply(i)); |
| } |
| } |
| |
| public int getFlag(int i) { |
| return proto.getFlag(i); |
| } |
| |
| /** |
| * Get the time elapsed for downstream ack RTT in nanoseconds |
| * @return time elapsed for downstream ack in nanoseconds, 0 if no next DN in pipeline |
| */ |
| public long getDownstreamAckTimeNanos() { |
| return proto.getDownstreamAckTimeNanos(); |
| } |
| |
| /** |
| * Check if this ack contains error status |
| * @return true if all statuses are SUCCESS |
| */ |
| public boolean isSuccess() { |
| for (Status s : proto.getReplyList()) { |
| if (s != Status.SUCCESS) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Returns the OOB status if this ack contains one. |
| * @return null if it is not an OOB ack. |
| */ |
| public Status getOOBStatus() { |
| // Normal data transfer acks will have a valid sequence number, so |
| // this will return right away in most cases. |
| if (getSeqno() != UNKOWN_SEQNO) { |
| return null; |
| } |
| for (Status s : proto.getReplyList()) { |
| // The following check is valid because protobuf guarantees to |
| // preserve the ordering of enum elements. |
| if (s.getNumber() >= OOB_START && s.getNumber() <= OOB_END) { |
| return s; |
| } |
| } |
| return null; |
| } |
| |
| /** Get the Restart OOB ack status */ |
| public static Status getRestartOOBStatus() { |
| return Status.OOB_RESTART; |
| } |
| |
| /** return true if it is the restart OOB status code */ |
| public static boolean isRestartOOBStatus(Status st) { |
| return st.equals(Status.OOB_RESTART); |
| } |
| |
| /**** Writable interface ****/ |
| public void readFields(InputStream in) throws IOException { |
| proto = PipelineAckProto.parseFrom(vintPrefixed(in)); |
| } |
| |
| public void write(OutputStream out) throws IOException { |
| proto.writeDelimitedTo(out); |
| } |
| |
| @Override //Object |
| public String toString() { |
| return TextFormat.shortDebugString(proto); |
| } |
| |
| public static Status getStatusFromHeader(int header) { |
| return StatusFormat.getStatus(header); |
| } |
| |
| public static ECN getECNFromHeader(int header) { |
| return StatusFormat.getECN(header); |
| } |
| |
| public static int setStatusForHeader(int old, Status status) { |
| return StatusFormat.setStatus(old, status); |
| } |
| |
| public static int combineHeader(ECN ecn, Status status) { |
| int header = 0; |
| header = StatusFormat.setStatus(header, status); |
| header = StatusFormat.setECN(header, ecn); |
| return header; |
| } |
| } |