Fix UserMetric calculation error

.. add a reference count for clones and originals, noting
   that for user metrics the factory gets a clone and the
   original is always deleted at startup.

.. additionally when the clone in the factory is deleted
   on metric changes we finally delete the program that
   was created initially.

.. note there is also a fix to let the configuration
   settings spot when aggregate zero and istime change
   in options as these were not spotted before.

src/Core/Context.cpp

@@ -99,6 +99,7 @@ Context::notifyConfigChanged(qint32 state)
 void 
 Context::userMetricsConfigChanged()
 {
+
     // read em in...
     QString metrics = QString("%1/../usermetrics.xml").arg(athlete->home->root().absolutePath());
     if (QFile(metrics).exists()) {
@@ -124,7 +125,7 @@ Context::userMetricsConfigChanged()
         // we'll fix it
         UserMetricSchemaVersion = changed;
 
-        // update metric factory 
+        // update metric factory deleting originals
         RideMetricFactory::instance().removeUserMetrics();
     
         // now add initial metrics -- what about multiple contexts (?) XXX

src/Core/DataFilter.h

@@ -169,6 +169,8 @@ class DataFilter : public QObject
 
         static QStringList builtins(); // return list of functions supported
 
+        int refcount; // used by user metrics
+
     public slots:
         QStringList parseFilter(Context *context, QString query, QStringList *list=0);
         QStringList check(QString query);

src/Metrics/UserMetric.cpp

@@ -25,6 +25,7 @@ UserMetric::UserMetric(Context *context, UserMetricSettings settings)
 {
     // compile the program - built in a context that can close.
     program = new DataFilter(NULL, context, settings.program);
+    program->refcount = 1;
     root = program->root();
     rt = &program->rt;
 
@@ -43,6 +44,7 @@ UserMetric::UserMetric(const UserMetric *from) : RideMetric()
 {
     this->settings = from->settings;
     this->program = from->program;
+    this->program->refcount++;
 
     this->root = from->program->root();
     this->finit = from->finit;
@@ -64,7 +66,11 @@ UserMetric::UserMetric(const UserMetric *from) : RideMetric()
 
 UserMetric::~UserMetric()
 {
-    if (!clone_ && program) delete program;
+    // program is shared, only delete when last is destroyed
+    if (program) {
+        program->refcount--;
+        if (!program->refcount) delete program;
+    }
     if (clone_) delete rt;
 }
 

src/Metrics/UserMetricSettings.h

@@ -57,6 +57,8 @@ class UserMetricSettings {
                 this->conversionSum != right.conversionSum ||
                 this->program != right.program ||
                 this->precision != right.precision ||
+                this->istime != right.istime ||
+                this->aggzero != right.aggzero ||
                 this->fingerprint != right.fingerprint)
                 return true;
             else