From 12d68e6021b48ca6599331aa3940977c46918bf8 Mon Sep 17 00:00:00 2001
From: Michael Davidsaver <mdavidsaver@gmail.com>
Date: Fri, 28 Apr 2017 18:37:14 -0400
Subject: [PATCH] ioc/db: Add dbCommonPvt

Add some hidden "fields" for every record.
Allows Base internal hidden accounting
which can be changed without an ABI break.
---
 src/ioc/db/dbAccess.c          |  5 +++--
 src/ioc/db/dbCommon.dbd        |  6 ------
 src/ioc/db/dbCommonPvt.h       | 14 ++++++++++++++
 src/ioc/dbStatic/dbStaticRun.c | 10 ++++++----
 4 files changed, 23 insertions(+), 12 deletions(-)
 create mode 100644 src/ioc/db/dbCommonPvt.h

diff --git a/src/ioc/db/dbAccess.c b/src/ioc/db/dbAccess.c
index 4fb25f0bd..ae21634b2 100644
--- a/src/ioc/db/dbAccess.c
+++ b/src/ioc/db/dbAccess.c
@@ -42,7 +42,7 @@
 #include "dbBase.h"
 #include "dbBkpt.h"
 #include "dbCa.h"
-#include "dbCommon.h"
+#include "dbCommonPvt.h"
 #include "dbConvertFast.h"
 #include "dbConvert.h"
 #include "dbEvent.h"
@@ -685,9 +685,10 @@ finish:
 void dbInitEntryFromChannel(struct dbAddr *paddr, DBENTRY *pdbentry)
 {
     struct dbCommon *prec = paddr->precord;
+    dbCommonPvt *ppvt = CONTAINER(prec, dbCommonPvt, common);
     pdbentry->pdbbase = pdbbase;
     pdbentry->precordType = prec->rdes;
-    pdbentry->precnode = prec->rnde;
+    pdbentry->precnode = ppvt->node;
     pdbentry->pflddes = paddr->pfldDes;
     pdbentry->pinfonode = NULL;
     pdbentry->pfield = paddr->pfield;
diff --git a/src/ioc/db/dbCommon.dbd b/src/ioc/db/dbCommon.dbd
index 2df9957b8..1b093e6a8 100644
--- a/src/ioc/db/dbCommon.dbd
+++ b/src/ioc/db/dbCommon.dbd
@@ -217,12 +217,6 @@
 		interest(4)
 		extra("struct dbRecordType *rdes")
 	}
-	field(RNDE,DBF_NOACCESS) {
-		prompt("Address of dbRecordNode")
-		special(SPC_NOMOD)
-		interest(4)
-		extra("struct dbRecordNode *rnde")
-	}
 	field(LSET,DBF_NOACCESS) {
 		prompt("Lock Set")
 		special(SPC_NOMOD)
diff --git a/src/ioc/db/dbCommonPvt.h b/src/ioc/db/dbCommonPvt.h
new file mode 100644
index 000000000..eddb12060
--- /dev/null
+++ b/src/ioc/db/dbCommonPvt.h
@@ -0,0 +1,14 @@
+#ifndef DBCOMMONPVT_H
+#define DBCOMMONPVT_H
+
+#include "dbCommon.h"
+
+/** Base internal additional information for every record
+ */
+typedef struct dbCommonPvt {
+    struct dbRecordNode *node;
+
+    struct dbCommon common;
+} dbCommonPvt;
+
+#endif // DBCOMMONPVT_H
diff --git a/src/ioc/dbStatic/dbStaticRun.c b/src/ioc/dbStatic/dbStaticRun.c
index a08322abf..0855a4d0f 100644
--- a/src/ioc/dbStatic/dbStaticRun.c
+++ b/src/ioc/dbStatic/dbStaticRun.c
@@ -25,7 +25,7 @@
 
 #define epicsExportSharedSymbols
 #include "dbBase.h"
-#include "dbCommon.h"
+#include "dbCommonPvt.h"
 #include "dbStaticLib.h"
 #include "dbStaticPvt.h"
 #include "devSup.h"
@@ -69,6 +69,7 @@ long dbAllocRecord(DBENTRY *pdbentry,const char *precordName)
     dbRecordNode	*precnode = pdbentry->precnode;
     dbFldDes		*pflddes;
     int			i;
+    dbCommonPvt *ppvt;
     dbCommon		*precord;
     char		*pfield;
     
@@ -85,8 +86,9 @@ long dbAllocRecord(DBENTRY *pdbentry,const char *precordName)
                     precordName, pdbRecordType->name, pdbRecordType->rec_size);
         return(S_dbLib_noRecSup);
     }
-    precord = dbCalloc(1, pdbRecordType->rec_size);
-    precord->rnde = precnode;
+    ppvt = dbCalloc(1, offsetof(dbCommonPvt, common) + pdbRecordType->rec_size);
+    precord = &ppvt->common;
+    ppvt->node = precnode;
     precnode->precord = precord;
     pflddes = pdbRecordType->papFldDes[0];
     if(!pflddes) {
@@ -171,7 +173,7 @@ long dbFreeRecord(DBENTRY *pdbentry)
     if(!pdbRecordType) return(S_dbLib_recordTypeNotFound);
     if(!precnode) return(S_dbLib_recNotFound);
     if(!precnode->precord) return(S_dbLib_recNotFound);
-    free(precnode->precord);
+    free(CONTAINER(precnode->precord, dbCommonPvt, common));
     precnode->precord = NULL;
     return(0);
 }