From 58b1db610c96befe7c0d3eca7c57a07eb7be7cc7 Mon Sep 17 00:00:00 2001
From: Ludovic Orban <lorban@bitronix.be>
Date: Tue, 4 Feb 2020 10:49:27 +0100
Subject: [PATCH] detectAndUpgrade() shortcut on empty buffer

Signed-off-by: Ludovic Orban <lorban@bitronix.be>
---
 .../eclipse/jetty/server/DetectorConnectionFactory.java    | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/jetty-server/src/main/java/org/eclipse/jetty/server/DetectorConnectionFactory.java b/jetty-server/src/main/java/org/eclipse/jetty/server/DetectorConnectionFactory.java
index 690563e5e2d..3f280a674d4 100644
--- a/jetty-server/src/main/java/org/eclipse/jetty/server/DetectorConnectionFactory.java
+++ b/jetty-server/src/main/java/org/eclipse/jetty/server/DetectorConnectionFactory.java
@@ -218,6 +218,13 @@ public class DetectorConnectionFactory extends AbstractConnectionFactory impleme
          */
         private boolean detectAndUpgrade()
         {
+            if (BufferUtil.isEmpty(_buffer))
+            {
+                if (LOG.isDebugEnabled())
+                    LOG.debug("Detector {} skipping detection on an empty buffer", getProtocol());
+                return false;
+            }
+
             if (LOG.isDebugEnabled())
                 LOG.debug("Detector {} performing detection with {} bytes", getProtocol(), _buffer.remaining());
             boolean notRecognized = true;