pcep/impl/src/main/java/org/opendaylight/protocol/pcep/impl/object/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.object;
   9
  10 import org.opendaylight.protocol.pcep.spi.ObjectParser;
  11 import org.opendaylight.protocol.pcep.spi.ObjectSerializer;
  12 import org.opendaylight.protocol.pcep.spi.PCEPDeserializerException;
  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<T> implements ObjectParser, ObjectSerializer {
  23
  24         private static final Logger LOG = 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 T builder, final byte[] bytes) throws PCEPDeserializerException {
  39                 if (bytes == null) {
  40                         throw new IllegalArgumentException("Byte array is mandatory.");
  41                 }
  42                 if (bytes.length == 0) {
  43                         return;
  44                 }
  45
  46                 int length;
  47                 int byteOffset = 0;
  48                 int type = 0;
  49
  50                 while (byteOffset < bytes.length) {
  51                         type = ByteArray.bytesToInt(ByteArray.subByte(bytes, byteOffset, TLV_TYPE_F_LENGTH));
  52                         byteOffset += TLV_TYPE_F_LENGTH;
  53                         length = ByteArray.bytesToInt(ByteArray.subByte(bytes, byteOffset, TLV_LENGTH_F_LENGTH));
  54                         byteOffset += TLV_LENGTH_F_LENGTH;
  55
  56                         if (TLV_HEADER_LENGTH + length > bytes.length) {
  57                                 throw new PCEPDeserializerException("Wrong length specified. Passed: " + (TLV_HEADER_LENGTH + length) + "; Expected: <= "
  58                                                 + (bytes.length - byteOffset) + ".");
  59                         }
  60
  61                         final byte[] tlvBytes = ByteArray.subByte(bytes, byteOffset, length);
  62
  63                         LOG.trace("Attempt to parse tlv from bytes: {}", ByteArray.bytesToHexString(tlvBytes));
  64                         final Tlv tlv = this.tlvReg.getTlvParser(type).parseTlv(tlvBytes);
  65                         LOG.trace("Tlv was parsed. {}", tlv);
  66
  67                         addTlv(builder, tlv);
  68
  69                         byteOffset += length + getPadding(TLV_HEADER_LENGTH + length, PADDED_TO);
  70                 }
  71         }
  72
  73         protected final byte[] serializeTlv(final Tlv tlv) {
  74
  75                 final TlvSerializer serializer = this.tlvReg.getTlvSerializer(tlv);
  76
  77                 final byte[] typeBytes = (ByteArray.cutBytes(ByteArray.intToBytes(serializer.getType()), (Integer.SIZE / 8) - TLV_TYPE_F_LENGTH));
  78
  79                 final byte[] valueBytes = serializer.serializeTlv(tlv);
  80
  81                 final byte[] lengthBytes = ByteArray.cutBytes(ByteArray.intToBytes(valueBytes.length), (Integer.SIZE / 8) - TLV_LENGTH_F_LENGTH);
  82
  83                 final byte[] bytes = new byte[TLV_HEADER_LENGTH + valueBytes.length + getPadding(TLV_HEADER_LENGTH + valueBytes.length, PADDED_TO)];
  84
  85                 int byteOffset = 0;
  86                 System.arraycopy(typeBytes, 0, bytes, byteOffset, TLV_TYPE_F_LENGTH);
  87                 byteOffset += TLV_TYPE_F_LENGTH;
  88                 System.arraycopy(lengthBytes, 0, bytes, byteOffset, TLV_LENGTH_F_LENGTH);
  89                 byteOffset += TLV_LENGTH_F_LENGTH;
  90                 System.arraycopy(valueBytes, 0, bytes, byteOffset, valueBytes.length);
  91                 return bytes;
  92         }
  93
  94         public abstract void addTlv(final T builder, final Tlv tlv);
  95
  96         protected static int getPadding(final int length, final int padding) {
  97                 return (padding - (length % padding)) % padding;
  98         }
  99 }