diff options
Diffstat (limited to 'src/main/java/org/traccar/protocol/L100FrameDecoder.java')
-rw-r--r-- | src/main/java/org/traccar/protocol/L100FrameDecoder.java | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/L100FrameDecoder.java b/src/main/java/org/traccar/protocol/L100FrameDecoder.java new file mode 100644 index 000000000..158461895 --- /dev/null +++ b/src/main/java/org/traccar/protocol/L100FrameDecoder.java @@ -0,0 +1,90 @@ +/* + * Copyright 2016 - 2018 Anton Tananaev (anton@traccar.org) + * + * Licensed 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.traccar.protocol; + +import io.netty.buffer.ByteBuf; +import io.netty.channel.Channel; +import io.netty.channel.ChannelHandlerContext; +import org.traccar.BaseFrameDecoder; + +import java.nio.charset.StandardCharsets; + +public class L100FrameDecoder extends BaseFrameDecoder { + + @Override + protected Object decode( + ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception { + + if (buf.readableBytes() < 10) { + return null; + } + + if (buf.getCharSequence(buf.readerIndex(), 4, StandardCharsets.US_ASCII).toString().equals("ATL,")) { + return decodeNew(buf); + } else { + return decodeOld(buf); + } + } + + private Object decodeOld(ByteBuf buf) { + + int header = buf.getByte(buf.readerIndex()); + boolean obd = header == 'L' || header == 'H'; + + int index; + if (obd) { + index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '*'); + } else { + index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) 0x02); + if (index < 0) { + index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) 0x04); + if (index < 0) { + return null; + } + } + } + + index += 2; // checksum + + if (buf.writerIndex() >= index) { + if (!obd) { + buf.skipBytes(2); // header + } + ByteBuf frame = buf.readRetainedSlice(index - buf.readerIndex() - 2); + buf.skipBytes(2); // footer + return frame; + } + + return null; + } + + private Object decodeNew(ByteBuf buf) { + + int index = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '@'); + if (index < 0) { + return null; + } + + if (buf.writerIndex() >= index + 1) { + ByteBuf frame = buf.readRetainedSlice(index - buf.readerIndex()); + buf.skipBytes(1); // delimiter + return frame; + } + + return null; + } + +} |