Add deadband plugin (client defined monitor deadband)

src/ioc/db/Makefile

@@ -85,4 +85,5 @@ dbCore_SRCS += dbIocRegister.c
 dbCore_SRCS += chfPlugin.c
 
 LIB_SRCS += ts.c
+LIB_SRCS += dbnd.c
 

src/ioc/db/filters/dbnd.c

@@ -0,0 +1,141 @@
+/*************************************************************************\
+* Copyright (c) 2010 Brookhaven National Laboratory.
+* Copyright (c) 2010 Helmholtz-Zentrum Berlin
+*     fuer Materialien und Energie GmbH.
+* EPICS BASE is distributed subject to a Software License Agreement found
+* in file LICENSE that is included with this distribution.
+\*************************************************************************/
+
+/*
+ *  Author: Ralph Lange <Ralph.Lange@bessy.de>
+ */
+#include <stdio.h>
+
+#include <epicsExport.h>
+#include <epicsMath.h>
+#include <freeList.h>
+#include <dbConvertFast.h>
+#include <chfPlugin.h>
+#include <db_field_log.h>
+
+typedef struct myStruct {
+    int    mode;
+    double cval;
+    double hyst;
+    double last;
+} myStruct;
+
+static void *myStructFreeList;
+
+static const
+chfPluginEnumType modeEnum[] = { {"abs", 0}, {"rel", 1}, {NULL,0} };
+
+static const
+chfPluginArgDef opts[] = {
+    chfDouble (myStruct, cval, "d", 0, 1),
+    chfEnum   (myStruct, mode, "m", 0, 1, modeEnum),
+    chfPluginArgEnd
+};
+
+void * allocPvt(void)
+{
+    return freeListCalloc(myStructFreeList);
+}
+
+void freePvt(void *pvt)
+{
+    freeListFree(myStructFreeList, pvt);
+}
+
+int parse_ok(void *pvt)
+{
+    myStruct *my = (myStruct*) pvt;
+    my->hyst = my->cval;
+    my->last = epicsNAN;
+    return 0;
+}
+
+static void shiftval (myStruct *my, double val) {
+    my->last = val;
+    if (my->mode == 1)
+        my->hyst = val * my->cval/100.;
+}
+
+static db_field_log* filter(void* pvt, dbChannel *chan, db_field_log *pfl) {
+    myStruct *my = (myStruct*) pvt;
+    long status;
+    double val, delta;
+    short drop = 0;
+
+    /*
+     * Only scalar values supported - strings, arrays, and conversion errors
+     * are just passed on
+     */
+    if (pfl->type == dbfl_type_val) {
+        DBADDR localAddr = chan->addr; /* Structure copy */
+        localAddr.field_type = pfl->field_type;
+        localAddr.field_size = pfl->field_size;
+        localAddr.no_elements = pfl->no_elements;
+        localAddr.pfield = (char *) &pfl->u.v.field;
+        status = dbFastGetConvertRoutine[pfl->field_type][DBR_DOUBLE]
+                 (localAddr.pfield, (void*) &val, &localAddr);
+        if (!status) {
+            if (isnan(my->last)) {
+                shiftval(my, val);
+            } else {
+                delta = fabs(my->last - val);
+                if (delta <= my->hyst) {
+                    drop = 1;
+                } else {
+                    shiftval(my, val);
+                }
+            }
+        }
+    }
+    if (drop) return NULL;
+    else return pfl;
+}
+
+static void channelRegisterPre(dbChannel *chan, void *pvt,
+                               chPostEventFunc **cb_out, void **arg_out, db_field_log *probe)
+{
+    *cb_out = filter;
+    *arg_out = pvt;
+}
+
+static void channel_report(dbChannel *chan, void *pvt, int level, const unsigned short indent)
+{
+    myStruct *my = (myStruct*) pvt;
+    printf("%*s  plugin dbnd, mode=%s, delta=%g%s\n", indent, "",
+           chfPluginEnumString(modeEnum, my->mode, "n/a"), my->cval,
+           my->mode == 1 ? "%" : "");
+}
+
+static chfPluginIf pif = {
+    allocPvt,
+    freePvt,
+
+    NULL, /* parse_error, */
+    parse_ok,
+
+    NULL, /* channel_open, */
+    channelRegisterPre,
+    NULL, /* channelRegisterPost, */
+    channel_report,
+    NULL /* channel_close */
+};
+
+static void dbndInitialize(void)
+{
+    static int firstTime = 1;
+
+    if (!firstTime) return;
+    firstTime = 0;
+
+    if (!myStructFreeList)
+        freeListInitPvt(&myStructFreeList, sizeof(myStruct), 64);
+
+    chfPluginRegister("dbnd", &pif, opts);
+}
+
+epicsExportRegistrar(dbndInitialize);

src/ioc/db/filters/filters.dbd

@@ -1 +1,2 @@
 registrar(tsInitialize)
+registrar(dbndInitialize)