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Diffstat (limited to 'src/main/java/org/traccar/protocol/NavigilFrameDecoder.java')
-rw-r--r--src/main/java/org/traccar/protocol/NavigilFrameDecoder.java56
1 files changed, 56 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/NavigilFrameDecoder.java b/src/main/java/org/traccar/protocol/NavigilFrameDecoder.java
new file mode 100644
index 000000000..e8b6bea52
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/NavigilFrameDecoder.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2013 - 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;
+
+public class NavigilFrameDecoder extends BaseFrameDecoder {
+
+ private static final int MESSAGE_HEADER = 20;
+ private static final long PREAMBLE = 0x2477F5F6;
+
+ @Override
+ protected Object decode(
+ ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
+
+ // Check minimum length
+ if (buf.readableBytes() < MESSAGE_HEADER) {
+ return null;
+ }
+
+ // Check for preamble
+ boolean hasPreamble = false;
+ if (buf.getUnsignedIntLE(buf.readerIndex()) == PREAMBLE) {
+ hasPreamble = true;
+ }
+
+ // Check length and return buffer
+ int length = buf.getUnsignedShortLE(buf.readerIndex() + 6);
+ if (buf.readableBytes() >= length) {
+ if (hasPreamble) {
+ buf.readUnsignedIntLE();
+ length -= 4;
+ }
+ return buf.readRetainedSlice(length);
+ }
+
+ return null;
+ }
+
+}