Propagate AMSG through MSS links

MS and MSI links do not propagate STAT and therefore do not propagate
AMSG, either. CA, CP and CPP links also do not propagate AMSG, but the
reason is technical: the message is not available over Channel Access.

Author: exzombie

modules/database/src/ioc/db/dbDbLink.c

@@ -226,9 +226,10 @@ static long dbDbGetValue(struct link *plink, short dbrType, void *pbuffer,
     }
 
     if (!status && precord != dbChannelRecord(chan))
-        recGblInheritSevr(plink->value.pv_link.pvlMask & pvlOptMsMode,
+        recGblInheritSevrMsg(plink->value.pv_link.pvlMask & pvlOptMsMode,
             plink->precord,
-            dbChannelRecord(chan)->stat, dbChannelRecord(chan)->sevr);
+            dbChannelRecord(chan)->stat, dbChannelRecord(chan)->sevr,
+            dbChannelRecord(chan)->amsg);
     return status;
 }
 
@@ -378,8 +379,8 @@ static long dbDbPutValue(struct link *plink, short dbrType,
     dbCommon *pdest = dbChannelRecord(chan);
     long status = dbPut(paddr, dbrType, pbuffer, nRequest);
 
-    recGblInheritSevr(ppv_link->pvlMask & pvlOptMsMode, pdest, psrce->nsta,
-        psrce->nsev);
+    recGblInheritSevrMsg(ppv_link->pvlMask & pvlOptMsMode, pdest, psrce->nsta,
+        psrce->nsev, psrce->namsg);
     if (status)
         return status;
 

modules/database/src/ioc/db/recGbl.c

@@ -260,8 +260,8 @@ int recGblSetSevr(void *precord, epicsEnum16 new_stat, epicsEnum16 new_sevr)
     return recGblSetSevrMsg(precord, new_stat, new_sevr, NULL);
 }
 
-void recGblInheritSevr(int msMode, void *precord, epicsEnum16 stat,
-    epicsEnum16 sevr)
+void recGblInheritSevrMsg(int msMode, void *precord, epicsEnum16 stat,
+    epicsEnum16 sevr, const char *msg)
 {
     switch (msMode) {
     case pvlOptNMS:
@@ -274,11 +274,17 @@ void recGblInheritSevr(int msMode, void *precord, epicsEnum16 stat,
         recGblSetSevr(precord, LINK_ALARM, sevr);
         break;
     case pvlOptMSS:
-        recGblSetSevr(precord, stat, sevr);
+        /* Only MSS inherits msg */
+        recGblSetSevrMsg(precord, stat, sevr, "%s", msg);
         break;
     }
 }
 
+void recGblInheritSevr(int msMode, void *precord, epicsEnum16 stat,
+    epicsEnum16 sevr)
+{
+    recGblInheritSevrMsg(msMode, precord, stat, sevr, NULL);
+}
 
 void recGblFwdLink(void *precord)
 {

modules/database/src/ioc/db/recGbl.h

@@ -73,6 +73,8 @@ DBCORE_API int recGblSetSevr(void *precord, epicsEnum16 new_stat,
     epicsEnum16 new_sevr);
 DBCORE_API void recGblInheritSevr(int msMode, void *precord, epicsEnum16 stat,
     epicsEnum16 sevr);
+DBCORE_API void recGblInheritSevrMsg(int msMode, void *precord, epicsEnum16 stat,
+    epicsEnum16 sevr, const char *msg);
 DBCORE_API int recGblSetSevrMsg(void *precord, epicsEnum16 new_stat,
                                 epicsEnum16 new_sevr,
                                 EPICS_PRINTF_FMT(const char *msg), ...) EPICS_PRINTF_STYLE(4,5);