Support new Xexun protocol (fix #4727)

1 files changed, 18 insertions, 9 deletions

diff --git a/src/main/java/org/traccar/helper/BufferUtil.java b/src/main/java/org/traccar/helper/BufferUtil.java
index b086f0f9e..bbf12d738 100644
--- a/src/main/java/org/traccar/helper/BufferUtil.java
+++ b/src/main/java/org/traccar/helper/BufferUtil.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 Anton Tananaev (anton@traccar.org)
+ * Copyright 2018 - 2021 Anton Tananaev (anton@traccar.org)
  * Copyright 2018 Andrey Kunitsyn (andrey@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -28,19 +28,28 @@ public final class BufferUtil {
     }
 
     public static int indexOf(String needle, ByteBuf haystack) {
-        ByteBuf needleBuffer = Unpooled.wrappedBuffer(needle.getBytes(StandardCharsets.US_ASCII));
+        return indexOf(needle, haystack, haystack.readerIndex(), haystack.writerIndex());
+    }
+
+    public static int indexOf(String needle, ByteBuf haystack, int startIndex, int endIndex) {
+        ByteBuf wrappedNeedle = Unpooled.wrappedBuffer(needle.getBytes(StandardCharsets.US_ASCII));
         try {
-            return ByteBufUtil.indexOf(needleBuffer, haystack);
+            return indexOf(wrappedNeedle, haystack, startIndex, endIndex);
         } finally {
-            needleBuffer.release();
+            wrappedNeedle.release();
         }
     }
 
-    public static int indexOf(String needle, ByteBuf haystack, int startIndex, int endIndex) {
-        ByteBuf wrappedHaystack = Unpooled.wrappedBuffer(haystack);
-        wrappedHaystack.readerIndex(startIndex - haystack.readerIndex());
-        wrappedHaystack.writerIndex(endIndex - haystack.readerIndex());
-        int result = indexOf(needle, wrappedHaystack);
+    public static int indexOf(ByteBuf needle, ByteBuf haystack, int startIndex, int endIndex) {
+        ByteBuf wrappedHaystack;
+        if (startIndex == haystack.readerIndex() && endIndex == haystack.writerIndex()) {
+            wrappedHaystack = haystack;
+        } else {
+            wrappedHaystack = Unpooled.wrappedBuffer(haystack);
+            wrappedHaystack.readerIndex(startIndex - haystack.readerIndex());
+            wrappedHaystack.writerIndex(endIndex - haystack.readerIndex());
+        }
+        int result = ByteBufUtil.indexOf(needle, wrappedHaystack);
         return result < 0 ? result : haystack.readerIndex() + startIndex + result;
     }