[1793] Eliminate several state variables

The values are deduced from something else, no need to keep them. This
eliminates the ugly initialization with wrong values.

src/bin/auth/command.cc

@@ -144,58 +144,45 @@ public:
 // Handle the "loadzone" command.
 class LoadZoneCommand : public AuthCommand {
 public:
-    LoadZoneCommand() :
-        // Just fill in something, these can't be created "without data",
-        // by constructor without parameters. These values will be overwritten
-        // in validate().
-        origin_(Name::ROOT_NAME()),
-        zone_class_(RRClass::IN())
-    { }
     virtual void exec(AuthSrv& server, isc::data::ConstElementPtr args) {
         // parse and validate the args.
         if (!validate(server, args)) {
             return;
         }
 
-        getZoneConfig(server);
+        const ConstElementPtr zone_config = getZoneConfig(server);
 
         // Load a new zone and replace the current zone with the new one.
         // TODO: eventually this should be incremental or done in some way
         // that doesn't block other server operations.
         // TODO: we may (should?) want to check the "last load time" and
         // the timestamp of the file and skip loading if the file isn't newer.
-        const ConstElementPtr type(zone_config_->get("filetype"));
+        const ConstElementPtr type(zone_config->get("filetype"));
         boost::shared_ptr<InMemoryZoneFinder> zone_finder(
-            new InMemoryZoneFinder(old_zone_finder->getClass(),
-                                   old_zone_finder->getOrigin()));
+            new InMemoryZoneFinder(old_zone_finder_->getClass(),
+                                   old_zone_finder_->getOrigin()));
         if (type && type->stringValue() == "sqlite3") {
             scoped_ptr<DataSourceClientContainer>
                 container(new DataSourceClientContainer("sqlite3",
                                                         Element::fromJSON(
                     "{\"database_file\": \"" +
-                    zone_config_->get("file")->stringValue() + "\"}")));
+                    zone_config->get("file")->stringValue() + "\"}")));
             zone_finder->load(*container->getInstance().getIterator(
-                old_zone_finder->getOrigin()));
+                old_zone_finder_->getOrigin()));
         } else {
-            zone_finder->load(old_zone_finder->getFileName());
+            zone_finder->load(old_zone_finder_->getFileName());
         }
-        old_zone_finder->swap(*zone_finder);
+        old_zone_finder_->swap(*zone_finder);
         LOG_DEBUG(auth_logger, DBG_AUTH_OPS, AUTH_LOAD_ZONE)
                   .arg(zone_finder->getOrigin()).arg(zone_finder->getClass());
     }
 
 private:
     // zone finder to be updated with the new file.
-    boost::shared_ptr<InMemoryZoneFinder> old_zone_finder;
-    // The configuration corresponding to the zone.
-    ConstElementPtr zone_config_;
-
-    // Parameters of the zone
-    Name origin_;
-    RRClass zone_class_;
+    boost::shared_ptr<InMemoryZoneFinder> old_zone_finder_;
 
     // A helper private method to parse and validate command parameters.
-    // On success, it sets 'old_zone_finder' to the zone to be updated.
+    // On success, it sets 'old_zone_finder_' to the zone to be updated.
     // It returns true if everything is okay; and false if the command is
     // valid but there's no need for further process.
     bool validate(AuthSrv& server, isc::data::ConstElementPtr args) {
@@ -220,11 +207,11 @@ private:
         }
 
         ConstElementPtr class_elem = args->get("class");
-        zone_class_ = class_elem ? RRClass(class_elem->stringValue()) :
-            RRClass::IN();
+        const RRClass zone_class =
+            class_elem ? RRClass(class_elem->stringValue()) : RRClass::IN();
 
         AuthSrv::InMemoryClientPtr datasrc(server.
-                                           getInMemoryClient(zone_class_));
+                                           getInMemoryClient(zone_class));
         if (datasrc == NULL) {
             isc_throw(AuthCommandError, "Memory data source is disabled");
         }
@@ -233,22 +220,22 @@ private:
         if (!origin_elem) {
             isc_throw(AuthCommandError, "Zone origin is missing");
         }
-        origin_ = Name(origin_elem->stringValue());
+        const Name origin = Name(origin_elem->stringValue());
 
         // Get the current zone
-        const InMemoryClient::FindResult result = datasrc->findZone(origin_);
+        const InMemoryClient::FindResult result = datasrc->findZone(origin);
         if (result.code != result::SUCCESS) {
-            isc_throw(AuthCommandError, "Zone " << origin_ <<
+            isc_throw(AuthCommandError, "Zone " << origin <<
                       " is not found in data source");
         }
 
-        old_zone_finder = boost::dynamic_pointer_cast<InMemoryZoneFinder>(
+        old_zone_finder_ = boost::dynamic_pointer_cast<InMemoryZoneFinder>(
             result.zone_finder);
 
         return (true);
     }
 
-    void getZoneConfig(const AuthSrv &server) {
+    ConstElementPtr getZoneConfig(const AuthSrv &server) {
         if (!server.getConfigSession()) {
             // FIXME: This is a hack to make older tests pass. We should
             // update these tests as well sometime and remove this hack.
@@ -257,8 +244,7 @@ private:
 
             // We provide an empty map, which means no configuration --
             // defaults.
-            zone_config_ = ConstElementPtr(new MapElement());
-            return;
+            return (ConstElementPtr(new MapElement()));
         }
 
         // Find the config corresponding to the zone.
@@ -282,7 +268,7 @@ private:
             // anyway and we may want to change the configuration of
             // datasources somehow.
             if (dsrc_config->get("type")->stringValue() == "memory" &&
-                RRClass(class_type) == zone_class_) {
+                RRClass(class_type) == old_zone_finder_->getClass()) {
                 zone_list = dsrc_config->get("zones");
                 break;
             }
@@ -296,18 +282,16 @@ private:
         // Now we need to walk the zones and find the correct one.
         for (size_t i(0); i < zone_list->size(); ++i) {
             const ConstElementPtr zone_config(zone_list->get(i));
-            if (Name(zone_config->get("origin")->stringValue()) == origin_) {
+            if (Name(zone_config->get("origin")->stringValue()) ==
+                old_zone_finder_->getOrigin()) {
                 // The origins are the same, so we consider this config to be
                 // for the zone.
-                zone_config_ = zone_config;
-                break;
+                return (zone_config);
             }
         }
 
-        if (!zone_config_) {
-            isc_throw(AuthCommandError,
-                      "Corresponding zone configuration was not found");
-        }
+        isc_throw(AuthCommandError,
+                  "Corresponding zone configuration was not found");
     }
 };