From 1f9e183d103d6f2ac100763c0280db3dc26adbec Mon Sep 17 00:00:00 2001
From: "Evgeny Grin (Karlson2k)" <k2k@narod.ru>
Date: Sun, 16 Jun 2019 23:17:20 +0300
Subject: [PATCH] process_request_body(): do not move data if nothing was
 processed

---
 src/microhttpd/connection.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/microhttpd/connection.c b/src/microhttpd/connection.c
index 9b8d3e2b..525e6a8c 100644
--- a/src/microhttpd/connection.c
+++ b/src/microhttpd/connection.c
@@ -2804,7 +2804,8 @@ process_request_body (struct MHD_Connection *connection)
         connection->remaining_upload_size -= processed_size;
     }
   while (MHD_YES == instant_retry);
-  if (available > 0)
+  if ( (available > 0) &&
+       (buffer_head != connection->read_buffer) )
     memmove (connection->read_buffer,
              buffer_head,
              available);