diff options
Diffstat (limited to 'src/main/java/org/traccar/protocol/AplicomFrameDecoder.java')
-rw-r--r-- | src/main/java/org/traccar/protocol/AplicomFrameDecoder.java | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/AplicomFrameDecoder.java b/src/main/java/org/traccar/protocol/AplicomFrameDecoder.java new file mode 100644 index 000000000..56fca27c7 --- /dev/null +++ b/src/main/java/org/traccar/protocol/AplicomFrameDecoder.java @@ -0,0 +1,62 @@ +/* + * Copyright 2013 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; + +public class AplicomFrameDecoder extends BaseFrameDecoder { + + @Override + protected Object decode( + ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception { + + // Skip Alive message + while (buf.isReadable() && Character.isDigit(buf.getByte(buf.readerIndex()))) { + buf.readByte(); + } + + // Check minimum length + if (buf.readableBytes() < 11) { + return null; + } + + // Read flags + int version = buf.getUnsignedByte(buf.readerIndex() + 1); + int offset = 1 + 1 + 3; + if ((version & 0x80) != 0) { + offset += 4; + } + + // Get data length + int length = buf.getUnsignedShort(buf.readerIndex() + offset); + offset += 2; + if ((version & 0x40) != 0) { + offset += 3; + } + length += offset; // add header + + // Return buffer + if (buf.readableBytes() >= length) { + return buf.readRetainedSlice(length); + } + + return null; + } + +} |