1 files changed, 81 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/protocol/ArnaviFrameDecoder.java b/src/main/java/org/traccar/protocol/ArnaviFrameDecoder.java
new file mode 100644
index 000000000..3db11113d
--- /dev/null
+++ b/src/main/java/org/traccar/protocol/ArnaviFrameDecoder.java
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2020 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 Ivan Muratov (binakot@gmail.com)
+ *
+ * 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 org.traccar.helper.BufferUtil;
+
+public class ArnaviFrameDecoder extends BaseFrameDecoder {
+
+    private static final int HEADER_LENGTH = 10;
+    private static final int PACKET_WRAPPER_LENGTH = 8;
+    private static final int RESULT_TYPE = 0xfd;
+    private static final byte PACKAGE_END_SIGN = 0x5d;
+
+    private boolean firstPacket = true;
+
+    @Override
+    protected Object decode(ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
+
+        if (buf.readableBytes() < 4) {
+            return null;
+        }
+
+        if (buf.getByte(buf.readerIndex()) == '$') {
+
+            int index = BufferUtil.indexOf("\r\n", buf);
+            if (index > 0) {
+                ByteBuf frame = buf.readRetainedSlice(index - buf.readerIndex());
+                buf.skipBytes(2);
+                return frame;
+            }
+
+        } else {
+
+            int length;
+            if (firstPacket) {
+                firstPacket = false;
+                length = HEADER_LENGTH;
+            } else {
+                int type = buf.getUnsignedByte(1);
+                if (type == RESULT_TYPE) {
+                    length = 4;
+                } else {
+                    int index = 2;
+                    while (index + PACKET_WRAPPER_LENGTH < buf.readableBytes() && buf.getByte(index) != PACKAGE_END_SIGN) {
+                        index += PACKET_WRAPPER_LENGTH + buf.getUnsignedShortLE(index + 1);
+                    }
+                    if (buf.getByte(index) != PACKAGE_END_SIGN) {
+                        return null;
+                    }
+                    length = index + 1;
+                }
+            }
+
+            if (buf.readableBytes() >= length) {
+                return buf.readRetainedSlice(length);
+            }
+
+        }
+
+        return null;
+    }
+
+}