From a8362bd087a16ee67a523bb0167ba1c4a62e91de Mon Sep 17 00:00:00 2001
From: John <ebusd@ebusd.eu>
Date: Fri, 28 Jun 2024 18:11:40 +0200
Subject: [PATCH] keep generated decode output and append it to error prefix on
 error

---
 src/ebusd/mainloop.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/ebusd/mainloop.cpp b/src/ebusd/mainloop.cpp
index c867563b..14a8a087 100644
--- a/src/ebusd/mainloop.cpp
+++ b/src/ebusd/mainloop.cpp
@@ -382,10 +382,15 @@ void MainLoop::run() {
         scanRetry = 0;  // restart scan counting
       }
       if (!req->isHttp() && (ostream.tellp() == 0 || result != RESULT_OK)) {
-        if (reqMode.listenMode != lm_direct) {
-          ostream.str("");
+        string suffix;
+        if (result == RESULT_EMPTY && ostream.tellp() > 0) {
+          suffix = ostream.str();
         }
+        ostream.str("");
         ostream << getResultCode(result);
+        if (!suffix.empty()) {
+          ostream << " " << suffix;
+        }
       }
       const auto resp = ostream.str();
       req->log(&resp);