Fix issue in Hua Sheng frame decoder

1 files changed, 18 insertions, 1 deletions

diff --git a/src/org/traccar/protocol/HuaShengFrameDecoder.java b/src/org/traccar/protocol/HuaShengFrameDecoder.java
index 5d68fef9e..0e1becc30 100644
--- a/src/org/traccar/protocol/HuaShengFrameDecoder.java
+++ b/src/org/traccar/protocol/HuaShengFrameDecoder.java
@@ -16,6 +16,7 @@
 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;
@@ -34,7 +35,23 @@ public class HuaShengFrameDecoder extends FrameDecoder {
 
         int index = buf.indexOf(buf.readerIndex() + 1, buf.writerIndex(), (byte) 0xC0);
         if (index != -1) {
-            return buf.readBytes(index + 1 - buf.readerIndex());
+            ChannelBuffer result = ChannelBuffers.buffer(index + 1 - buf.readerIndex());
+
+            while (buf.readerIndex() <= index) {
+                int b = buf.readUnsignedByte();
+                if (b == 0xDB) {
+                    int ext = buf.readUnsignedByte();
+                    if (ext == 0xDC) {
+                        result.writeByte(0xC0);
+                    } else if (ext == 0xDD) {
+                        result.writeByte(0xDB);
+                    }
+                } else {
+                    result.writeByte(b);
+                }
+            }
+
+            return result;
         }
 
         return null;