From 1182cd177155d639368038cf0cb3cb4541cdb7ff Mon Sep 17 00:00:00 2001
From: Michael Zillgith <michael.zillgith@mz-automation.de>
Date: Thu, 15 Feb 2024 20:32:54 +0000
Subject: [PATCH] - MMS client: avoid invoke ID 0 as it is used as return value
 of client function in case of an error

---
 src/mms/iso_mms/client/mms_client_connection.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/mms/iso_mms/client/mms_client_connection.c b/src/mms/iso_mms/client/mms_client_connection.c
index 6f743b0b..0ba12801 100644
--- a/src/mms/iso_mms/client/mms_client_connection.c
+++ b/src/mms/iso_mms/client/mms_client_connection.c
@@ -1,7 +1,7 @@
 /*
  *  mms_client_connection.c
  *
- *  Copyright 2013-2022 Michael Zillgith
+ *  Copyright 2013-2024 Michael Zillgith
  *
  *  This file is part of libIEC61850.
  *
@@ -242,6 +242,10 @@ getNextInvokeId(MmsConnection self)
 
     Semaphore_wait(self->nextInvokeIdLock);
     self->nextInvokeId++;
+
+    if (self->nextInvokeId == 0)
+        self->nextInvokeId = 1;
+
     nextInvokeId = self->nextInvokeId;
     Semaphore_post(self->nextInvokeIdLock);