From 0a1fb25e6bb9523f69b69d845706028c35ac72ca Mon Sep 17 00:00:00 2001
From: Dirk Zimoch <dirk.zimoch@psi.ch>
Date: Mon, 29 Jun 2020 22:23:21 +0200
Subject: [PATCH] fix dbCaGetLink to fail when reading scalars from empty
 arrays

---
 modules/database/src/ioc/db/dbCa.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/modules/database/src/ioc/db/dbCa.c b/modules/database/src/ioc/db/dbCa.c
index 4ae39bbce..28e0df6d8 100644
--- a/modules/database/src/ioc/db/dbCa.c
+++ b/modules/database/src/ioc/db/dbCa.c
@@ -410,9 +410,15 @@ long dbCaGetLink(struct link *plink, short dbrType, void *pdest,
         goto done;
     }
     newType = dbDBRoldToDBFnew[pca->dbrType];
-    if (!nelements || *nelements == 1) {
+    if (!nelements) {
         long (*fConvert)(const void *from, void *to, struct dbAddr *paddr);
 
+        if (pca->usedelements < 1) {
+            pca->sevr = INVALID_ALARM;
+            pca->stat = LINK_ALARM;
+            status = -1;
+            goto done;
+        }
         fConvert = dbFastGetConvertRoutine[newType][dbrType];
         assert(pca->pgetNative);
         status = fConvert(pca->pgetNative, pdest, 0);