Open Session - Invoke modifyPort RPC only if required

client/port.cpp

@@ -454,6 +454,40 @@ void Port::getModifiedDeviceGroupsSinceLastSync(
                                 ->CopyFrom(*deviceGroupById(id));
 }
 
+/*!
+ * Finds the user modifiable fields in 'config' that are different from
+ * the current configuration on the port and modifes 'config' such that
+ * only those fields are set and returns true. If 'config' is same as
+ * current port config, 'config' is unmodified and false is returned
+ */
+bool Port::modifiablePortConfig(OstProto::Port &config) const
+{
+    bool change = false;
+    OstProto::Port modCfg;
+
+    if (config.is_exclusive_control() != d.is_exclusive_control()) {
+        modCfg.set_is_exclusive_control(config.is_exclusive_control());
+        change = true;
+    }
+    if (config.transmit_mode() != d.transmit_mode()) {
+        modCfg.set_transmit_mode(config.transmit_mode());
+        change = true;
+    }
+    if (config.user_name() != d.user_name()) {
+        modCfg.set_user_name(config.user_name());
+        change = true;
+    }
+
+    if (change) {
+        modCfg.mutable_port_id()->set_id(id());
+        config.CopyFrom(modCfg);
+
+        return true;
+    }
+
+    return false;
+}
+
 void Port::when_syncComplete()
 {
     //reorderStreamsByOrdinals();

client/port.h

@@ -155,6 +155,8 @@ public:
     void getModifiedDeviceGroupsSinceLastSync(
             OstProto::DeviceGroupConfigList &streamConfigList);
 
+    bool modifiablePortConfig(OstProto::Port &config) const;
+
     void when_syncComplete();
 
     void setAveragePacketRate(double packetsPerSec);

client/portgroup.cpp

@@ -862,15 +862,14 @@ void PortGroup::processStreamIdList(int portIndex, PbRpcController *controller)
                             controller));
         }
 
-        // modify port FIXME: check if there's actually any change
+        OstProto::Port portCfg = newPortContent->port_config();
-        if (newPortContent->has_port_config())
+        if (mPorts[portIndex]->modifiablePortConfig(portCfg))
         {
             OstProto::PortConfigList *portConfigList =
                     new OstProto::PortConfigList;
             OstProto::Port *port = portConfigList->add_port();
-            port->CopyFrom(newPortContent->port_config());
+            port->CopyFrom(portCfg);
-            port->mutable_port_id()->set_id(portId); // overwrite
+            if (port->has_user_name())
-            if (newPortContent->port_config().has_user_name())
                 port->set_user_name(qPrintable(myself)); // overwrite
 
             OstProto::Ack *ack = new OstProto::Ack;