minor

informational, and a hint at what pvt points to

src/ioc/db/dbCa.c

@@ -314,6 +314,7 @@ void dbCaAddLinkCallback(struct link *plink,
     plink->lset = &dbCa_lset;
     plink->type = CA_LINK;
     plink->value.pv_link.pvt = pca;
+    plink->value.pv_link.backend = "ca";
     addAction(pca, CA_CONNECT);
     epicsMutexUnlock(pca->lock);
 }
@@ -332,6 +333,7 @@ void dbCaRemoveLink(struct dbLocker *locker, struct link *plink)
     epicsMutexMustLock(pca->lock);
     pca->plink = 0;
     plink->value.pv_link.pvt = 0;
+    plink->value.pv_link.backend = NULL;
     plink->value.pv_link.pvlMask = 0;
     plink->type = PV_LINK;
     plink->lset = NULL;
@@ -709,6 +711,8 @@ static void scanLinkOnce(dbCommon *prec, caLink *pca) {
 }
 
 static lset dbCa_lset = {
+    LSET_API_VERSION,
+    dbCaReportLink,
     dbCaRemoveLink,
     isConnected,
     getDBFtype, getElements,

src/ioc/db/dbCa.h

@@ -20,6 +20,8 @@ extern "C" {
 typedef void (*dbCaCallback)(void *userPvt);
 epicsShareFunc void dbCaCallbackProcess(void *usrPvt);
 
+#ifdef EPICS_DBCA_PRIVATE_API
+
 epicsShareFunc void dbCaLinkInit(void); /* internal initialization for iocBuild()  */
 epicsShareFunc void dbCaLinkInitIsolated(void); /* internal initialization for iocBuildIsolated()  */
 epicsShareFunc void dbCaRun(void);
@@ -47,8 +49,10 @@ epicsShareFunc long dbCaPutLink(struct link *plink,short dbrType,
 
 extern struct ca_client_context * dbCaClientContext;
 
-#ifdef EPICS_DBCA_PRIVATE_API
 epicsShareFunc void dbCaSync(void);
+epicsShareFunc void dbCaReportLink(const struct link *plink, dbLinkReportInfo *pinfo);
+epicsShareExtern void (*dbAddLinkHook)(struct link *link, short dbfType);
+epicsShareFunc void dbSetBrokenLink(struct link *link, short dbfType);
 #endif
 
 /* These macros are for backwards compatibility */

src/ioc/db/dbCaTest.c

@@ -20,6 +20,7 @@
 #include <string.h>
 #include <errno.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "dbDefs.h"
 #include "epicsEvent.h"
 #include "epicsPrint.h"
@@ -52,7 +53,61 @@
 #include "dbLock.h"
 #include "link.h"
 
-
+void dbCaReportLink(const struct link *plink, dbLinkReportInfo *pinfo)
+{
+    caLink * const pca = (caLink *)plink->value.pv_link.pvt;
+    const char * fname = dbGetFieldName(pinfo->pentry),
+               * rname = dbGetRecordName(pinfo->pentry);
+
+    assert(pca);
+    epicsMutexLock(pca->lock);
+    assert(pca->plink==plink);
+
+    pinfo->connected = ca_field_type(pca->chid) != TYPENOTCONN;
+    pinfo->nWriteFail = pca->nNoWrite;
+    pinfo->nDisconnect = pca->nDisconnect;
+
+    if (pinfo->connected) {
+        pinfo->readable = ca_read_access(pca->chid);
+        pinfo->writable = ca_write_access(pca->chid);
+
+        if (pinfo->filter==dbLinkReportAll || pinfo->filter==dbLinkReportConnected) {
+            int rw = pinfo->readable |
+                     pinfo->writable << 1;
+            static const char *rights[4] = {
+                "No Access", "Read Only",
+                "Write Only", "Read/Write"
+            };
+            int mask = plink->value.pv_link.pvlMask;
+            printf(LSET_REPORT_INDENT "%28s.%-4s ==> %-28s  (%lu, %lu)\n",
+                rname,
+                fname,
+                plink->value.pv_link.pvname,
+                pca->nDisconnect,
+                pca->nNoWrite);
+            printf(LSET_REPORT_INDENT "%21s [%s%s%s%s] host %s, %s\n", "",
+                mask & pvlOptInpNative ? "IN" : "  ",
+                mask & pvlOptInpString ? "IS" : "  ",
+                mask & pvlOptOutNative ? "ON" : "  ",
+                mask & pvlOptOutString ? "OS" : "  ",
+                ca_host_name(pca->chid),
+                rights[rw]);
+        }
+    } else {
+        if (pinfo->filter==dbLinkReportAll || pinfo->filter==dbLinkReportDisconnected) {
+            printf(LSET_REPORT_INDENT "%28s.%-4s --> %-28s  (%lu, %lu)\n",
+                rname,
+                fname,
+                plink->value.pv_link.pvname,
+                pca->nDisconnect,
+                pca->nNoWrite);
+        }
+    }
+
+    epicsMutexUnlock(pca->lock);
+}
+
+
 long dbcar(char *precordname, int level)
 {
     DBENTRY             dbentry;
@@ -68,7 +123,7 @@ long dbcar(char *precordname, int level)
     int                 noWriteAccess=0;
     unsigned long       nDisconnect=0;
     unsigned long       nNoWrite=0;
-    caLink              *pca;
+
     int                 j;
 
     if (!precordname || precordname[0] == '\0' || !strcmp(precordname, "*")) {
@@ -90,50 +145,26 @@ long dbcar(char *precordname, int level)
                 dbScanLock(precord);
                 for (j=0; j<pdbRecordType->no_links; j++) {
                     pdbFldDes = pdbRecordType->papFldDes[pdbRecordType->link_ind[j]];
+                    pdbentry->pflddes = pdbFldDes;
                     plink = (DBLINK *)((char *)precord + pdbFldDes->offset);
                     if (plink->type == CA_LINK) {
                         ncalinks++;
-                        pca = (caLink *)plink->value.pv_link.pvt;
-                        if (pca
-                        && pca->chid
-                        && (ca_field_type(pca->chid) != TYPENOTCONN)) {
-                            nconnected++;
-                            nDisconnect += pca->nDisconnect;
-                            nNoWrite += pca->nNoWrite;
-                            if (!ca_read_access(pca->chid)) noReadAccess++;
-                            if (!ca_write_access(pca->chid)) noWriteAccess++;
-                            if (level>1) {
-                                int rw = ca_read_access(pca->chid) |
-                                         ca_write_access(pca->chid) << 1;
-                                static const char *rights[4] = {
-                                    "No Access", "Read Only",
-                                    "Write Only", "Read/Write"
-                                };
-                                int mask = plink->value.pv_link.pvlMask;
-                                printf("%28s.%-4s ==> %-28s  (%lu, %lu)\n",
-                                    precord->name,
-                                    pdbFldDes->name,
-                                    plink->value.pv_link.pvname,
-                                    pca->nDisconnect,
-                                    pca->nNoWrite);
-                                printf("%21s [%s%s%s%s] host %s, %s\n", "",
-                                    mask & pvlOptInpNative ? "IN" : "  ",
-                                    mask & pvlOptInpString ? "IS" : "  ",
-                                    mask & pvlOptOutNative ? "ON" : "  ",
-                                    mask & pvlOptOutString ? "OS" : "  ",
-                                    ca_host_name(pca->chid),
-                                    rights[rw]);
-                            }
-                        } else {
-                            if (level>0) {
-                                printf("%28s.%-4s --> %-28s  (%lu, %lu)\n",
-                                    precord->name,
-                                    pdbFldDes->name,
-                                    plink->value.pv_link.pvname,
-                                    pca->nDisconnect,
-                                    pca->nNoWrite);
-                            }
-                        }
+                        dbLinkReportInfo linfo;
+                        memset(&linfo, 0, sizeof(linfo));
+                        linfo.pentry = pdbentry;
+                        if(level==0)
+                            linfo.filter = dbLinkReportNone;
+                        else if(level==1)
+                            linfo.filter = dbLinkReportDisconnected;
+                        else
+                            linfo.filter = dbLinkReportAll;
+                        if(level>2)
+                            linfo.detailLevel = level-2;
+                        dbReportLink(plink, &linfo);
+                        nconnected += linfo.connected;
+                        nDisconnect += linfo.nDisconnect;
+                        noReadAccess += !linfo.readable;
+                        noWriteAccess += !linfo.writable;
                     }
                 }
                 dbScanUnlock(precord);
@@ -190,7 +221,7 @@ void dbcaStats(int *pchans, int *pdiscon)
                     plink = (DBLINK *)((char *)precord + pdbFldDes->offset);
                     if (plink->type == CA_LINK) {
                         ncalinks++;
-                        if (dbCaIsLinkConnected(plink)) {
+                        if (dbIsLinkConnected(plink)) {
                             nconnected++;
                         }
                     }

src/ioc/db/dbLink.c

@@ -18,6 +18,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "cantProceed.h"
 #include "cvtFast.h"
@@ -139,6 +140,8 @@ static long dbConstGetValue(struct link *plink, short dbrType, void *pbuffer,
 }
 
 static lset dbConst_lset = {
+    LSET_API_VERSION,
+    NULL,
     NULL,
     NULL,
     NULL, dbConstGetNelements,
@@ -170,6 +173,7 @@ static long dbDbInitLink(struct link *plink, short dbfType)
     pdbAddr = dbCalloc(1, sizeof(struct dbAddr));
     *pdbAddr = dbaddr; /* structure copy */
     plink->value.pv_link.pvt = pdbAddr;
+    plink->value.pv_link.backend = "db";
     ellAdd(&dbaddr.precord->bklnk, &plink->value.pv_link.backlinknode);
     /* merging into the same lockset is deferred to the caller.
      * cf. initPVLinks()
@@ -184,6 +188,7 @@ static void dbDbAddLink(dbLocker *locker, struct link *plink, short dbfType, DBA
     plink->lset = &dbDb_lset;
     plink->type = DB_LINK;
     plink->value.pv_link.pvt = ptarget;
+    plink->value.pv_link.backend = "db";
     ellAdd(&ptarget->precord->bklnk, &plink->value.pv_link.backlinknode);
 
     /* target record is already locked in dbPutFieldLink() */
@@ -194,6 +199,7 @@ static void dbDbRemoveLink(dbLocker *locker, struct link *plink)
 {
     DBADDR *pdbAddr = (DBADDR *) plink->value.pv_link.pvt;
     plink->value.pv_link.pvt = 0;
+    plink->value.pv_link.backend = NULL;
     plink->value.pv_link.getCvt = 0;
     plink->value.pv_link.pvlMask = 0;
     plink->value.pv_link.lastGetdbrType = 0;
@@ -431,6 +437,8 @@ static void dbDbScanFwdLink(struct link *plink)
 }
 
 static lset dbDb_lset = {
+    LSET_API_VERSION,
+    NULL,
     dbDbRemoveLink,
     dbDbIsConnected,
     dbDbGetDBFtype, dbDbGetElements,
@@ -442,8 +450,87 @@ static lset dbDb_lset = {
     dbDbScanFwdLink
 };
 
+static void dbBrokenReportLink(const struct link *plink, dbLinkReportInfo *pinfo)
+{
+    const char * fname = dbGetFieldName(pinfo->pentry),
+               * rname = dbGetRecordName(pinfo->pentry);
+
+    if (pinfo->filter==dbLinkReportAll || pinfo->filter==dbLinkReportDisconnected) {
+        printf("%28s.%-4s --> %-28s <invalid link type>\n",
+            rname,
+            fname,
+            plink->value.pv_link.pvname);
+    }
+}
+
+static void dbBrokenRemoveLink(dbLocker *locker, struct link *plink)
+{
+    assert(!plink->value.pv_link.pvt);
+    plink->value.pv_link.pvt = 0;
+    plink->value.pv_link.backend = NULL;
+    plink->value.pv_link.getCvt = 0;
+    plink->value.pv_link.pvlMask = 0;
+    plink->value.pv_link.lastGetdbrType = 0;
+    plink->type = PV_LINK;
+    plink->lset = NULL;
+}
+
+static lset broken_lset = {
+    LSET_API_VERSION,
+    dbBrokenReportLink,
+    dbBrokenRemoveLink
+};
+
 /***************************** Generic Link API *****************************/
 
+void dbSetBrokenLink(struct link *plink, short dbfType)
+{
+    plink->lset = &broken_lset;
+    plink->type = CA_LINK;
+    plink->value.pv_link.pvt = NULL;
+    plink->value.pv_link.backend = "invalid";
+}
+
+static
+void dbCaAddLinkHook(struct link *plink, short dbfType)
+{
+    dbCaAddLink(NULL, plink, dbfType);
+}
+
+void (*dbAddLinkHook)(struct link *link, short dbfType) = &dbCaAddLinkHook;
+
+/* initialize CA_LINK with possibly custom lset */
+static
+void customlset(struct link *plink, short dbfType)
+{
+    int oops = 0;
+    plink->lset = NULL;
+    if(dbAddLinkHook)
+        (*dbAddLinkHook)(plink, dbfType);
+
+    if((plink->lset==NULL) ^ (plink->type==PV_LINK)) {
+        oops = 1;
+        errlogPrintf("custom link types must set both type and lset.\n");
+    }
+    if(plink->lset && plink->lset->version!=LSET_API_VERSION) {
+        oops = 1;
+        errlogPrintf("custom link types must set .version to LSET_API_VERSION (%u) not %u\n",
+                     LSET_API_VERSION, plink->lset->version);
+    }
+    if(oops)
+    {
+        plink->lset = NULL;
+        plink->type = PV_LINK;
+        plink->value.pv_link.pvt = NULL; /* leaking */
+    }
+
+    if(!plink->lset)
+        dbSetBrokenLink(plink, dbfType); /* install "invalid" lset as fallback */
+    assert(plink->lset);
+    assert(plink->type==CA_LINK);
+    assert(plink->lset->version==LSET_API_VERSION);
+}
+
 void dbInitLink(struct link *plink, short dbfType)
 {
     struct dbCommon *precord = plink->precord;
@@ -469,7 +556,7 @@ void dbInitLink(struct link *plink, short dbfType)
     if (dbfType == DBF_INLINK)
         plink->value.pv_link.pvlMask |= pvlOptInpNative;
 
-    dbCaAddLink(NULL, plink, dbfType);
+    customlset(plink, dbfType);
     if (dbfType == DBF_FWDLINK) {
         char *pperiod = strrchr(plink->value.pv_link.pvname, '.');
 
@@ -508,7 +595,7 @@ void dbAddLink(dbLocker *locker, struct link *plink, short dbfType, DBADDR *ptar
     if (dbfType == DBF_INLINK)
         plink->value.pv_link.pvlMask |= pvlOptInpNative;
 
-    dbCaAddLink(locker, plink, dbfType);
+    customlset(plink, dbfType);
     if (dbfType == DBF_FWDLINK) {
         char *pperiod = strrchr(plink->value.pv_link.pvname, '.');
 
@@ -537,6 +624,15 @@ void dbRemoveLink(dbLocker *locker, struct link *plink)
     }
 }
 
+void dbReportLink(const struct link *plink, dbLinkReportInfo *pinfo)
+{
+    lset *plset = plink->lset;
+
+    if (plset && plset->reportLink) {
+        plset->reportLink(plink, pinfo);
+    }
+}
+
 int dbIsLinkConnected(const struct link *plink)
 {
     lset *plset = plink->lset;

src/ioc/db/dbLink.h

@@ -26,8 +26,37 @@ extern "C" {
 #endif
 
 struct dbLocker;
+struct DBENTRY;
+
+#define LSET_API_VERSION 1
+#define LSET_REPORT_INDENT ""
+
+typedef enum {
+    dbLinkReportNone,
+    dbLinkReportAll,
+    dbLinkReportConnected,
+    dbLinkReportDisconnected,
+} dbLinkReportFilter;
+
+typedef struct {
+    /* from caller */
+    dbLinkReportFilter filter;
+    int detailLevel;
+    struct DBENTRY *pentry;
+    unsigned clearstats:1; /* after reporting, zero stat counters */
+    /* callee fills in current state */
+    unsigned connected:1; /* is this link connected to it's underlying data source */
+    unsigned readable:1;  /* would a dbGetLink() succeed at this moment */
+    unsigned writable:1;  /* would a dbPutLink() succeed at this moment */
+    /* callee fills in statistics */
+    unsigned nDisconnect; /* number of times this link has entered a not connected state */
+    unsigned nEvents;     /* number of times new data has been received from the underlying data source */
+    unsigned nWriteFail;  /* number of times dbPutLink() has failed for this link */
+} dbLinkReportInfo;
 
 typedef struct lset {
+    unsigned version; /* must be set to LSET_API_VERSION */
+    void (*reportLink)(const struct link *plink, dbLinkReportInfo *pinfo);
     void (*removeLink)(struct dbLocker *locker, struct link *plink);
     int (*isConnected)(const struct link *plink);
     int (*getDBFtype)(const struct link *plink);
@@ -58,6 +87,8 @@ epicsShareFunc long dbLoadLink(struct link *plink, short dbrType,
         void *pbuffer);
 epicsShareFunc void dbRemoveLink(struct dbLocker *locker, struct link *plink);
 
+epicsShareFunc void dbReportLink(const struct link *plink, dbLinkReportInfo *pinfo);
+
 epicsShareFunc long dbGetNelements(const struct link *plink, long *nelements);
 epicsShareFunc int dbIsLinkConnected(const struct link *plink);
 epicsShareFunc int dbGetLinkDBFtype(const struct link *plink);

src/ioc/db/initHooks.h

@@ -48,6 +48,14 @@ typedef enum {
     initHookAfterDatabasePaused,
     initHookAfterIocPaused,         /* End of iocPause command */
 
+    initHookAtIocShutdown,          /* Start of iocShutdown */
+    initHookAfterCaLinkClose,
+    initHookAfterScanShutdown,
+    initHookAfterCallbackShutdown,
+    initHookAfterCaServerStopped,
+    initHookAfterDatabaseStopped,
+    initHookAfterIocShutdown,       /* End of iocShutdown */
+
 /* Deprecated states, provided for backwards compatibility.
  * These states are announced at the same point they were before,
  * but will not be repeated if the IOC gets paused and restarted.

src/ioc/db/test/dbCaLinkTest.c

@@ -13,6 +13,7 @@
 #include <string.h>
 #include <math.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "epicsString.h"
 #include "dbUnitTest.h"
 #include "epicsThread.h"

src/ioc/dbStatic/dbStaticLib.h

@@ -47,7 +47,7 @@ extern "C" {
 
 typedef dbBase DBBASE;
 
-typedef struct{
+typedef struct DBENTRY {
     DBBASE       *pdbbase;
     dbRecordType *precordType;
     dbFldDes     *pflddes;

src/ioc/dbStatic/link.h

@@ -85,6 +85,7 @@ struct pv_link {
     LINKCVT	getCvt;		/* input conversion function */
     short	pvlMask;	/* Options mask */
     short	lastGetdbrType;	/* last dbrType for DB or CA get */
+    const char *backend;/* informational string describing the backend */
 };
 
 /* structure of a VME io channel */

src/ioc/misc/iocInit.c

@@ -23,6 +23,7 @@
 #include <errno.h>
 #include <limits.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "dbDefs.h"
 #include "ellLib.h"
 #include "envDefs.h"
@@ -641,7 +642,7 @@ static void doCloseLinks(dbRecordType *pdbRecordType, dbCommon *precord,
                 dbScanLock(precord);
                 locked = 1;
             }
-            dbCaRemoveLink(NULL, plink);
+            dbRemoveLink(NULL, plink);
 
         } else if (iocBuildMode==buildIsolated && plink->type == DB_LINK) {
             /* free link, but don't split lockset like dbDbRemoveLink() */
@@ -688,13 +689,20 @@ static void doFreeRecord(dbRecordType *pdbRecordType, dbCommon *precord,
 int iocShutdown(void)
 {
     if (iocState == iocVirgin || iocState == iocStopped) return 0;
+    initHookAnnounce(initHookAtIocShutdown); // TODO: iterate hooks in reverse
     iterateRecords(doCloseLinks, NULL);
+    initHookAnnounce(initHookAfterCaLinkClose);
     if (iocBuildMode==buildIsolated) {
         /* stop and "join" threads */
         scanStop();
+        initHookAnnounce(initHookAfterScanShutdown);
         callbackStop();
+        initHookAnnounce(initHookAfterCallbackShutdown);
     }
     dbCaShutdown(); /* must be before dbFreeRecord and dbChannelExit */
+    initHookAnnounce(initHookAfterCaServerStopped);
+    /* placeholder, RSRV will eventually stop here */
+    initHookAnnounce(initHookAfterDatabaseStopped);
     if (iocBuildMode==buildIsolated) {
         /* free resources */
         scanCleanup();
@@ -708,6 +716,7 @@ int iocShutdown(void)
     }
     iocState = iocStopped;
     iocBuildMode = buildRSRV;
+    initHookAnnounce(initHookAfterIocShutdown);
     return 0;
 }
 

src/std/dev/devAoSoftCallback.c

@@ -17,6 +17,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbDefs.h"
 #include "dbAccess.h"
@@ -55,7 +56,7 @@ static long write_ao(aoRecord *prec)
     long status;
 
     if(prec->pact) return(0);
-    if(plink->type!=CA_LINK) {
+    if(plink->type!=CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         status = dbPutLink(plink,DBR_DOUBLE,&prec->oval,1);
         return(status);
     }

src/std/dev/devBoSoftCallback.c

@@ -19,6 +19,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbDefs.h"
 #include "dbLock.h"
@@ -55,7 +56,7 @@ static long write_bo(boRecord *prec)
     long status;
 
     if(prec->pact) return(0);
-    if(plink->type!=CA_LINK) {
+    if(plink->type!=CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         status = dbPutLink(plink,DBR_USHORT,&prec->val,1);
         return(status);
     }

src/std/dev/devCalcoutSoftCallback.c

@@ -17,6 +17,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbDefs.h"
 #include "dbAccess.h"
@@ -49,7 +50,7 @@ static long write_calcout(calcoutRecord *prec)
     long status;
 
     if (prec->pact) return 0;
-    if (plink->type != CA_LINK) {
+    if (plink->type != CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         status = dbPutLink(plink, DBR_DOUBLE, &prec->oval, 1);
         return status;
     }

src/std/dev/devLoSoftCallback.c

@@ -18,6 +18,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbDefs.h"
 #include "dbAccess.h"
@@ -52,7 +53,7 @@ static long write_longout(longoutRecord	*prec)
     long status;
 
     if(prec->pact) return(0);
-    if(plink->type!=CA_LINK) {
+    if(plink->type!=CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         status = dbPutLink(plink,DBR_LONG,&prec->val,1);
         return(status);
     }

src/std/dev/devLsoSoftCallback.c

@@ -10,6 +10,9 @@
  *      Date:   30 Nov 2012
  */
 
+#include <string.h>
+
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbAccess.h"
 #include "recGbl.h"
@@ -31,7 +34,7 @@ static long write_string(lsoRecord *prec)
         len = 1;
     }
 
-    if (plink->type != CA_LINK)
+    if (plink->type != CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0)
         return dbPutLink(plink, dtyp, prec->val, len);
 
     status = dbCaPutLinkCallback(plink, dtyp, prec->val, len,

src/std/dev/devMbboDirectSoftCallback.c

@@ -13,7 +13,9 @@
  */
 
 #include <stdio.h>
+#include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbAccess.h"
 #include "recGbl.h"
@@ -29,7 +31,7 @@ static long write_mbbo(mbboDirectRecord *prec)
     if (prec->pact)
         return 0;
 
-    if (plink->type != CA_LINK) {
+    if (plink->type != CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         status = dbPutLink(plink, DBR_USHORT, &prec->val, 1);
         return status;
     }

src/std/dev/devMbboSoftCallback.c

@@ -17,6 +17,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbDefs.h"
 #include "dbAccess.h"
@@ -51,7 +52,7 @@ static long write_mbbo(mbboRecord *prec)
     long status;
 
     if(prec->pact) return(0);
-    if(plink->type!=CA_LINK) {
+    if(plink->type!=CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         status = dbPutLink(plink,DBR_USHORT,&prec->val,1);
         return(status);
     }

src/std/dev/devPrintfSoftCallback.c

@@ -10,6 +10,9 @@
  *      Date:   28 Sept 2012
  */
 
+#include <string.h>
+
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbAccess.h"
 #include "recGbl.h"
@@ -31,7 +34,7 @@ static long write_string(printfRecord *prec)
         len = 1;
     }
 
-    if (plink->type != CA_LINK)
+    if (plink->type != CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0)
         return dbPutLink(plink, dtyp, prec->val, len);
 
     status = dbCaPutLinkCallback(plink, dtyp, prec->val, len,

src/std/dev/devSoSoftCallback.c

@@ -17,6 +17,7 @@
 #include <stdio.h>
 #include <string.h>
 
+#define EPICS_DBCA_PRIVATE_API
 #include "alarm.h"
 #include "dbDefs.h"
 #include "dbAccess.h"
@@ -52,7 +53,7 @@ static long write_stringout(stringoutRecord *prec)
 
     if (prec->pact) return 0;
 
-    if (plink->type != CA_LINK) {
+    if (plink->type != CA_LINK || strcmp(plink->value.pv_link.backend,"ca")!=0) {
         return dbPutLink(plink, DBR_STRING, &prec->val, 1);
     }