Implement custom HuaSheng frame decoder

2 files changed, 45 insertions, 1 deletions

diff --git a/src/org/traccar/protocol/HuaShengFrameDecoder.java b/src/org/traccar/protocol/HuaShengFrameDecoder.java
new file mode 100644
index 000000000..922bc3979
--- /dev/null
+++ b/src/org/traccar/protocol/HuaShengFrameDecoder.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2016 Anton Tananaev (anton.tananaev@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 org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import org.jboss.netty.channel.Channel;
+import org.jboss.netty.channel.ChannelHandlerContext;
+import org.jboss.netty.handler.codec.frame.FrameDecoder;
+
+public class HuaShengFrameDecoder extends FrameDecoder {
+
+    @Override
+    protected Object decode(
+            ChannelHandlerContext ctx,
+            Channel channel,
+            ChannelBuffer buf) throws Exception {
+
+        if (buf.readableBytes() < 2) {
+            return null;
+        }
+
+        int index = buf.indexOf(buf.readerIndex() + 1, buf.writerIndex(), (byte) 0xC0);
+        if (index != -1) {
+            return buf.readBytes(index + 1 - buf.readerIndex());
+        }
+
+        return null;
+    }
+
+}
diff --git a/src/org/traccar/protocol/HuaShengProtocol.java b/src/org/traccar/protocol/HuaShengProtocol.java
index 7c1d48860..351f886db 100644
--- a/src/org/traccar/protocol/HuaShengProtocol.java
+++ b/src/org/traccar/protocol/HuaShengProtocol.java
@@ -34,7 +34,7 @@ public class HuaShengProtocol extends BaseProtocol {
         serverList.add(new TrackerServer(new ServerBootstrap(), this.getName()) {
             @Override
             protected void addSpecificHandlers(ChannelPipeline pipeline) {
-                pipeline.addLast("frameDecoder", new LengthFieldBasedFrameDecoder(1024, 3, 2, 0, 0));
+                pipeline.addLast("frameDecoder", new HuaShengFrameDecoder());
                 pipeline.addLast("objectDecoder", new HuaShengProtocolDecoder(HuaShengProtocol.this));
             }
         });