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

   1 package org.opendaylight.protocol.pcep.impl.message;
   2
   3 import java.util.Arrays;
   4 import java.util.BitSet;
   5 import java.util.List;
   6
   7 import org.opendaylight.protocol.pcep.PCEPDeserializerException;
   8 import org.opendaylight.protocol.pcep.spi.MessageParser;
   9 import org.opendaylight.protocol.pcep.spi.MessageSerializer;
  10 import org.opendaylight.protocol.pcep.spi.ObjectHandlerRegistry;
  11 import org.opendaylight.protocol.pcep.spi.ObjectParser;
  12 import org.opendaylight.protocol.pcep.spi.ObjectSerializer;
  13 import org.opendaylight.protocol.pcep.spi.PCEPErrorMapping;
  14 import org.opendaylight.protocol.pcep.spi.PCEPErrors;
  15 import org.opendaylight.protocol.util.ByteArray;
  16 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.message.rev131007.PcerrBuilder;
  17 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Message;
  18 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Object;
  19 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.ObjectHeader;
  20 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.PcerrMessage;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcep.error.object.ErrorObjectBuilder;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.PcerrMessageBuilder;
  23 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.pcerr.message.pcerr.message.ErrorsBuilder;
  24
  25 import com.google.common.base.Preconditions;
  26 import com.google.common.collect.Lists;
  27 import com.google.common.primitives.UnsignedBytes;
  28
  29 public abstract class AbstractMessageParser implements MessageParser, MessageSerializer {
  30
  31         private static final int COMMON_OBJECT_HEADER_LENGTH = 4;
  32
  33         private static final int OC_F_LENGTH = 1;
  34         private static final int OT_FLAGS_MF_LENGTH = 1;
  35         private static final int OBJ_LENGTH_F_LENGTH = 2;
  36
  37         private static final int OC_F_OFFSET = 0;
  38         private static final int OT_FLAGS_MF_OFFSET = OC_F_OFFSET + OC_F_LENGTH;
  39         private static final int OBJ_LENGTH_F_OFFSET = OT_FLAGS_MF_OFFSET + OT_FLAGS_MF_LENGTH;
  40
  41         private static final int OT_SF_LENGTH = 4;
  42         private static final int FLAGS_SF_LENGTH = 4;
  43
  44         /*
  45          * offsets of fields inside of multi-field in bits
  46          */
  47         private static final int OT_SF_OFFSET = 0;
  48         private static final int FLAGS_SF_OFFSET = OT_SF_OFFSET + OT_SF_LENGTH;
  49
  50         /*
  51          * flags offsets inside multi-filed
  52          */
  53         private static final int P_FLAG_OFFSET = 6;
  54         private static final int I_FLAG_OFFSET = 7;
  55
  56         private final ObjectHandlerRegistry registry;
  57
  58         protected AbstractMessageParser(final ObjectHandlerRegistry registry) {
  59                 this.registry = Preconditions.checkNotNull(registry);
  60         }
  61
  62         protected byte[] serializeObject(final Object object) {
  63                 if (object == null) {
  64                         throw new IllegalArgumentException("Null object passed.");
  65                 }
  66
  67                 final ObjectSerializer serializer = this.registry.getObjectSerializer(object);
  68
  69                 final byte[] valueBytes = serializer.serializeObject(object);
  70
  71                 final byte[] retBytes = new byte[COMMON_OBJECT_HEADER_LENGTH + valueBytes.length];
  72
  73                 // objClass
  74                 retBytes[OC_F_OFFSET] = UnsignedBytes.checkedCast(serializer.getObjectClass());
  75
  76                 // objType_flags multi-field
  77                 retBytes[OT_FLAGS_MF_OFFSET] = UnsignedBytes.checkedCast(serializer.getObjectType() << (Byte.SIZE - OT_SF_LENGTH));
  78                 if (object.isProcessingRule() != null && object.isProcessingRule()) {
  79                         retBytes[OT_FLAGS_MF_OFFSET] |= 1 << Byte.SIZE - (P_FLAG_OFFSET) - 1;
  80                 }
  81                 if (object.isIgnore() != null && object.isIgnore()) {
  82                         retBytes[OT_FLAGS_MF_OFFSET] |= 1 << Byte.SIZE - (I_FLAG_OFFSET) - 1;
  83                 }
  84
  85                 // objLength
  86                 System.arraycopy(ByteArray.intToBytes(valueBytes.length + COMMON_OBJECT_HEADER_LENGTH), Integer.SIZE / Byte.SIZE
  87                                 - OBJ_LENGTH_F_LENGTH, retBytes, OBJ_LENGTH_F_OFFSET, OBJ_LENGTH_F_LENGTH);
  88
  89                 ByteArray.copyWhole(valueBytes, retBytes, COMMON_OBJECT_HEADER_LENGTH);
  90                 return retBytes;
  91         }
  92
  93         private final List<Object> parseObjects(final byte[] bytes) throws PCEPDeserializerException {
  94                 int offset = 0;
  95                 final List<Object> objs = Lists.newArrayList();
  96                 while (bytes.length - offset > 0) {
  97                         if (bytes.length - offset < COMMON_OBJECT_HEADER_LENGTH) {
  98                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
  99                                                 + COMMON_OBJECT_HEADER_LENGTH + ".");
 100                         }
 101
 102                         final int objClass = UnsignedBytes.toInt(bytes[offset]);
 103
 104                         offset += OC_F_LENGTH;
 105
 106                         final int objType = UnsignedBytes.toInt(ByteArray.copyBitsRange(bytes[offset], OT_SF_OFFSET, OT_SF_LENGTH));
 107
 108                         final byte[] flagsBytes = { ByteArray.copyBitsRange(bytes[offset], FLAGS_SF_OFFSET, FLAGS_SF_LENGTH) };
 109
 110                         final BitSet flags = ByteArray.bytesToBitSet(flagsBytes);
 111
 112                         offset += OT_FLAGS_MF_LENGTH;
 113
 114                         final int objLength = ByteArray.bytesToInt(ByteArray.subByte(bytes, offset, OBJ_LENGTH_F_LENGTH));
 115
 116                         if (bytes.length - offset < objLength - COMMON_OBJECT_HEADER_LENGTH) {
 117                                 throw new PCEPDeserializerException("Too few bytes in passed array. Passed: " + (bytes.length - offset) + " Expected: >= "
 118                                                 + objLength + ".");
 119                         }
 120
 121                         offset += OBJ_LENGTH_F_LENGTH;
 122
 123                         // copy bytes for deeper parsing
 124                         final byte[] bytesToPass = ByteArray.subByte(bytes, offset, objLength - COMMON_OBJECT_HEADER_LENGTH);
 125
 126                         offset += objLength - COMMON_OBJECT_HEADER_LENGTH;
 127
 128                         final ObjectParser parser = Preconditions.checkNotNull(this.registry.getObjectParser(objClass, objType));
 129                         final ObjectHeader header = new ObjectHeaderImpl(flags.get(P_FLAG_OFFSET), flags.get(I_FLAG_OFFSET));
 130
 131                         // parseObject is required to return null for P=0 errored objects
 132                         final Object o = parser.parseObject(header, bytesToPass);
 133                         if (o != null) {
 134                                 objs.add(o);
 135                         }
 136                 }
 137
 138                 return objs;
 139         }
 140
 141         public static PcerrMessage createErrorMsg(final PCEPErrors e) {
 142                 final PCEPErrorMapping maping = PCEPErrorMapping.getInstance();
 143                 return new PcerrBuilder().setPcerrMessage(
 144                                 new PcerrMessageBuilder().setErrors(
 145                                                 Arrays.asList(new ErrorsBuilder().setErrorObject(
 146                                                                 new ErrorObjectBuilder().setType(maping.getFromErrorsEnum(e).type).setValue(
 147                                                                                 maping.getFromErrorsEnum(e).value).build()).build())).build()).build();
 148         }
 149
 150         abstract protected Message validate(final List<Object> objects, final List<Message> errors) throws PCEPDeserializerException;
 151
 152         @Override
 153         public final Message parseMessage(final byte[] buffer, final List<Message> errors) throws PCEPDeserializerException {
 154                 Preconditions.checkNotNull(buffer, "Buffer may not be null");
 155
 156                 // Parse objects first
 157                 final List<Object> objs = parseObjects(buffer);
 158
 159                 // Run validation
 160                 return validate(objs, errors);
 161         }
 162 }