From 5f02ea166132b3901a3f104ae5b6fb622d4b7b39 Mon Sep 17 00:00:00 2001
From: Michael Zillgith <michael.zillgith@mz-automation.de>
Date: Thu, 4 Jun 2020 10:36:12 +0200
Subject: [PATCH] - IEC 61850 server: control module return AddCause
 command-already-in-execution when second operate is received while command is
 executed

---
 src/iec61850/server/mms_mapping/control.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/iec61850/server/mms_mapping/control.c b/src/iec61850/server/mms_mapping/control.c
index d1b2b582..0116572a 100644
--- a/src/iec61850/server/mms_mapping/control.c
+++ b/src/iec61850/server/mms_mapping/control.c
@@ -1783,6 +1783,18 @@ Control_writeAccessControlObject(MmsMapping* self, MmsDomain* domain, char* vari
 
             goto free_and_return;
         }
+        else if ((state == STATE_OPERATE) || (state == STATE_WAIT_FOR_EXECUTION)) {
+            if (DEBUG_IED_SERVER)
+                printf("IED_SERVER: Oper failed - control already being executed!\n");
+
+            indication = DATA_ACCESS_ERROR_TEMPORARILY_UNAVAILABLE;
+
+            ControlObject_sendLastApplError(controlObject, connection, "Oper",
+                    CONTROL_ERROR_NO_ERROR, ADD_CAUSE_COMMAND_ALREADY_IN_EXECUTION,
+                    ctlNum, origin, true);
+
+            goto free_and_return;
+        }
     }
     else if (strcmp(varName, "Cancel") == 0) {
         if (DEBUG_IED_SERVER)