pcep/impl/src/main/java/org/opendaylight/protocol/pcep/impl/message/AbstractObjectWithTlvsParser.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.protocol.pcep.impl.message;
   9
  10 import org.opendaylight.protocol.pcep.PCEPDeserializerException;
  11 import org.opendaylight.protocol.pcep.spi.ObjectParser;
  12 import org.opendaylight.protocol.pcep.spi.ObjectSerializer;
  13 import org.opendaylight.protocol.pcep.spi.TlvHandlerRegistry;
  14 import org.opendaylight.protocol.pcep.spi.TlvSerializer;
  15 import org.opendaylight.protocol.util.ByteArray;
  16 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Tlv;
  17 import org.slf4j.Logger;
  18 import org.slf4j.LoggerFactory;
  19
  20 import com.google.common.base.Preconditions;
  21
  22 public abstract class AbstractObjectWithTlvsParser<BUILDER> implements ObjectParser, ObjectSerializer {
  23
  24         private static final Logger logger = LoggerFactory.getLogger(AbstractObjectWithTlvsParser.class);
  25
  26         private static final int TLV_TYPE_F_LENGTH = 2;
  27         private static final int TLV_LENGTH_F_LENGTH = 2;
  28         private static final int TLV_HEADER_LENGTH = TLV_LENGTH_F_LENGTH + TLV_TYPE_F_LENGTH;
  29
  30         protected static final int PADDED_TO = 4;
  31
  32         private final TlvHandlerRegistry tlvReg;
  33
  34         protected AbstractObjectWithTlvsParser(final TlvHandlerRegistry tlvReg) {
  35                 this.tlvReg = Preconditions.checkNotNull(tlvReg);
  36         }
  37
  38         protected final void parseTlvs(final BUILDER builder, final byte[] bytes) throws PCEPDeserializerException {
  39                 if (bytes == null) {
  40                         throw new IllegalArgumentException("Byte array is mandatory.");
  41                 }
  42
  43                 int length;
  44                 int byteOffset = 0;
  45                 int type = 0;
  46
  47                 while (byteOffset < bytes.length) {
  48                         type = ByteArray.bytesToInt(ByteArray.subByte(bytes, byteOffset, TLV_TYPE_F_LENGTH));
  49                         byteOffset += TLV_TYPE_F_LENGTH;
  50                         length = ByteArray.bytesToInt(ByteArray.subByte(bytes, byteOffset, TLV_LENGTH_F_LENGTH));
  51                         byteOffset += TLV_LENGTH_F_LENGTH;
  52
  53                         if (TLV_HEADER_LENGTH + length > bytes.length - byteOffset) {
  54                                 throw new PCEPDeserializerException("Wrong length specified. Passed: " + (TLV_HEADER_LENGTH + length) + "; Expected: <= "
  55                                                 + (bytes.length - byteOffset) + ".");
  56                         }
  57
  58                         final byte[] tlvBytes = ByteArray.subByte(bytes, byteOffset, length);
  59
  60                         logger.trace("Attempt to parse tlv from bytes: {}", ByteArray.bytesToHexString(tlvBytes));
  61                         final Tlv tlv = this.tlvReg.getTlvParser(type).parseTlv(tlvBytes);
  62                         logger.trace("Tlv was parsed. {}", tlv);
  63
  64                         addTlv(builder, tlv);
  65
  66                         byteOffset += length + getPadding(TLV_HEADER_LENGTH + length, PADDED_TO);
  67                 }
  68         }
  69
  70         protected final byte[] serializeTlv(final Tlv tlv) {
  71
  72                 final TlvSerializer serializer = this.tlvReg.getTlvSerializer(tlv);
  73
  74                 final byte[] typeBytes = (ByteArray.cutBytes(ByteArray.intToBytes(serializer.getType()), (Integer.SIZE / 8) - TLV_TYPE_F_LENGTH));
  75
  76                 final byte[] valueBytes = serializer.serializeTlv(tlv);
  77
  78                 final byte[] lengthBytes = ByteArray.cutBytes(ByteArray.intToBytes(valueBytes.length), (Integer.SIZE / 8) - TLV_LENGTH_F_LENGTH);
  79
  80                 final byte[] bytes = new byte[TLV_HEADER_LENGTH + valueBytes.length + getPadding(TLV_HEADER_LENGTH + valueBytes.length, PADDED_TO)];
  81
  82                 int byteOffset = 0;
  83                 System.arraycopy(typeBytes, 0, bytes, byteOffset, TLV_TYPE_F_LENGTH);
  84                 System.arraycopy(lengthBytes, 0, bytes, byteOffset += TLV_TYPE_F_LENGTH, TLV_LENGTH_F_LENGTH);
  85                 System.arraycopy(valueBytes, 0, bytes, byteOffset += TLV_LENGTH_F_LENGTH, valueBytes.length);
  86                 return bytes;
  87         }
  88
  89         public abstract void addTlv(final BUILDER builder, final Tlv tlv);
  90
  91         private static int getPadding(final int length, final int padding) {
  92                 return (padding - (length % padding)) % padding;
  93         }
  94 }