fix(config): reject empty reflector host entries

src/ratecontroller.rs

@@ -491,7 +491,7 @@ impl<S: InterfaceStatsProvider, T: TrafficControlBackend> Ratecontroller<S, T> {
         self.state_dl.deltas = down_deltas;
         self.state_ul.deltas = up_deltas;
 
-        let minimum = usize::from(self.settings.reflectors.num_reflectors);
+        let minimum = usize::from(self.settings.reflectors.num_reflectors).min(reflectors.len());
         if self.state_dl.deltas.len() < minimum || self.state_ul.deltas.len() < minimum {
             // trigger reselection
             warn!(

src/settings/validation.rs

@@ -213,6 +213,12 @@ impl ReflectorSettings {
         }
 
         for (index, reflector) in self.entries.iter().enumerate() {
+            if reflector.host.trim().is_empty() {
+                report.error(
+                    "reflectors.entries",
+                    format!("entry {index} must have a nonempty host"),
+                );
+            }
             if reflector.protocols.is_empty() {
                 report.error(
                     "reflectors.entries",