Fix aai constant initialization

The aai record is "special" and does things its own way.
These changes let it support {const:[...]} initialization without
breaking regular input link types which could be initialized twice
without the new DBLINK_FLAG_INITIALIZED guard in dbInitLink().

Also adds tests for this, and for similar links for waveform.

src/ioc/db/dbLink.c

@@ -73,6 +73,12 @@ void dbInitLink(struct link *plink, short dbfType)
 {
     struct dbCommon *precord = plink->precord;
 
+    /* Only initialize link once */
+    if (plink->flags & DBLINK_FLAG_INITIALIZED)
+        return;
+    else
+        plink->flags |= DBLINK_FLAG_INITIALIZED;
+
     if (plink->type == CONSTANT) {
         dbConstInitLink(plink);
         return;

src/ioc/dbStatic/link.h

@@ -69,6 +69,8 @@ epicsShareExtern maplinkType pamaplinkType[];
 #define pvlOptOutString  0x400	/*Output as string*/
 #define pvlOptTSELisTime 0x800	/*Field TSEL is getting timeStamp*/
 
+/* DBLINK Flag bits */
+#define DBLINK_FLAG_INITIALIZED    1 /* dbInitLink() called */
 
 struct macro_link {
     char *macroStr;

src/std/dev/devAaiSoft.c

@@ -4,7 +4,7 @@
 * Copyright (c) 2002 The Regents of the University of California, as
 *     Operator of Los Alamos National Laboratory.
 * EPICS BASE is distributed subject to a Software License Agreement found
-* in file LICENSE that is included with this distribution. 
+* in file LICENSE that is included with this distribution.
 \*************************************************************************/
 
 /*
@@ -53,7 +53,12 @@ epicsExportAddress(dset,devAaiSoft);
 
 static long init_record(aaiRecord *prec)
 {
-    if (prec->inp.type == CONSTANT) {
+    DBLINK *plink = &prec->inp;
+
+    /* This is pass 0, link hasn't been initialized yet */
+    dbInitLink(plink, DBF_INLINK);
+
+    if (dbLinkIsConstant(plink)) {
         long nRequest = prec->nelm;
         long status;
 
@@ -63,10 +68,7 @@ static long init_record(aaiRecord *prec)
                 "devAaiSoft: buffer calloc failed");
         }
 
-        /* This is pass 0 so link hasn't been initialized either */
-        dbConstInitLink(&prec->inp);
-
-        status = dbLoadLinkArray(&prec->inp, prec->ftvl, prec->bptr, &nRequest);
+        status = dbLoadLinkArray(plink, prec->ftvl, prec->bptr, &nRequest);
         if (!status && nRequest > 0) {
             prec->nord = nRequest;
             prec->udf = FALSE;

src/std/rec/test/linkInitTest.c

@@ -138,17 +138,23 @@ static void testArrayInputs()
 
     testdbGetFieldEqual("aai1.NORD", DBR_LONG, 10);
     testdbGetFieldEqual("aai1.UDF", DBR_UCHAR, 0);
+    testdbGetFieldEqual("aai2.NORD", DBR_LONG, 10);
+    testdbGetFieldEqual("aai2.UDF", DBR_UCHAR, 0);
     testdbGetFieldEqual("sa1.NORD", DBR_LONG, 10);
     testdbGetFieldEqual("sa1.UDF", DBR_UCHAR, 0);
     testdbGetFieldEqual("sa2.NORD", DBR_LONG, 0);
     testdbGetFieldEqual("sa2.UDF", DBR_UCHAR, 1);
     testdbGetFieldEqual("wf1.NORD", DBR_LONG, 10);
     testdbGetFieldEqual("wf1.UDF", DBR_UCHAR, 0);
+    testdbGetFieldEqual("wf2.NORD", DBR_LONG, 10);
+    testdbGetFieldEqual("wf2.UDF", DBR_UCHAR, 0);
 
     testdbGetArrFieldEqual("aai1.VAL", DBF_LONG, 12, 10, &oneToTwelve[0]);
+    testdbGetArrFieldEqual("aai2.VAL", DBF_LONG, 12, 10, &oneToTwelve[0]);
     testdbGetArrFieldEqual("sa1.VAL", DBF_LONG, 12, 10, &oneToTwelve[2]);
     testdbGetArrFieldEqual("sa2.VAL", DBF_LONG, 10, 0, NULL);
     testdbGetArrFieldEqual("wf1.VAL", DBF_LONG, 12, 10, &oneToTwelve[0]);
+    testdbGetArrFieldEqual("wf2.VAL", DBF_LONG, 12, 10, &oneToTwelve[0]);
 
     testdbPutFieldOk("sa1.INDX", DBF_LONG, 3);
     testdbGetArrFieldEqual("sa1.VAL", DBF_LONG, 12, 9, &oneToTwelve[3]);
@@ -200,7 +206,7 @@ static void testEventRecord()
 
 MAIN(linkInitTest)
 {
-    testPlan(62);
+    testPlan(68);
 
     testLongStringInit();
     testCalcInit();

src/std/rec/test/linkInitTest.db

@@ -31,11 +31,16 @@ record(printf, "printf2") {
   field(INP0, ["Longer test string, more that 40 characters long"])
 }
 
-record(waveform, "aai1") {
+record(aai, "aai1") {
   field(NELM, 10)
   field(FTVL, "LONG")
   field(INP, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12])
 }
+record(aai, "aai2") {
+  field(NELM, 10)
+  field(FTVL, "LONG")
+  field(INP, {const:[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]})
+}
 record(subArray, "sa1") {
   field(FTVL, "LONG")
   field(MALM, 12)
@@ -53,6 +58,11 @@ record(waveform, "wf1") {
   field(FTVL, "LONG")
   field(INP, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12])
 }
+record(waveform, "wf2") {
+  field(NELM, 10)
+  field(FTVL, "LONG")
+  field(INP, {const:[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]})
+}
 
 record(longin, "count1" ) {
   field(INP, {calc: {expr:"VAL+1"}})