Improve frame decoder

1 files changed, 23 insertions, 13 deletions

diff --git a/src/main/java/org/traccar/protocol/ItsFrameDecoder.java b/src/main/java/org/traccar/protocol/ItsFrameDecoder.java
index 79b341760..eb2c59e91 100644
--- a/src/main/java/org/traccar/protocol/ItsFrameDecoder.java
+++ b/src/main/java/org/traccar/protocol/ItsFrameDecoder.java
@@ -19,30 +19,40 @@ 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 ItsFrameDecoder extends BaseFrameDecoder {
 
+    private static final int MINIMUM_LENGTH = 20;
+
     @Override
     protected Object decode(
             ChannelHandlerContext ctx, Channel channel, ByteBuf buf) throws Exception {
 
-        int delimiterIndex = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '*');
-
-        if (buf.writerIndex() > delimiterIndex + 1 && buf.getByte(delimiterIndex + 1) == '*') {
-            delimiterIndex += 1;
-        }
-
         ByteBuf frame;
-        if (buf.getByte(delimiterIndex - 2) == ',') {
-            frame = buf.readRetainedSlice(delimiterIndex - 1 - buf.readerIndex());
-            buf.skipBytes(1); // binary checksum
-        } else {
+        int delimiterIndex = BufferUtil.indexOf("\r\n", buf);;
+        if (delimiterIndex > MINIMUM_LENGTH) {
             frame = buf.readRetainedSlice(delimiterIndex - buf.readerIndex());
+            buf.skipBytes(2);
+            return frame;
+        } else {
+            delimiterIndex = buf.indexOf(buf.readerIndex(), buf.writerIndex(), (byte) '*');
+            if (delimiterIndex > MINIMUM_LENGTH) {
+                if (buf.writerIndex() > delimiterIndex + 1 && buf.getByte(delimiterIndex + 1) == '*') {
+                    delimiterIndex += 1;
+                }
+                if (buf.getByte(delimiterIndex - 2) == ',') {
+                    frame = buf.readRetainedSlice(delimiterIndex - 1 - buf.readerIndex());
+                    buf.skipBytes(1); // binary checksum
+                } else {
+                    frame = buf.readRetainedSlice(delimiterIndex - buf.readerIndex());
+                }
+                buf.skipBytes(1); // delimiter
+                return frame;
+            }
         }
 
-        buf.skipBytes(1); // delimiter
-
-        return frame;
+        return null;
     }
 
 }