fix: Delete options for virtual network script

hack/virtual-network.sh

@@ -1,15 +1,39 @@
 #!/bin/bash -ex
 
-# Create a venv-based virtual network for testing, consisting of:
+# Manage a venv-based virtual network for testing, consisting of:
 #
 # - venv0: Interface for the DHCP server (static address: 10.0.0.254/24)
 # - venv1: Interface for DHCP client
 # - br-dhcp: A bridge for communication between these interfaces
+#
+# Default behavior is to create the network, the `-d` option removes it.
 
 BR=br-dhcp
 SERVERADDR="10.0.0.254/24"
 
+# Parse arguments
+DELETE=0
+while getopts "d" opt; do
+    case $opt in
+        d)
+            DELETE=1
+            ;;
+        *)
+            ;;
+    esac
+done
+
+if [ "$DELETE" != "0" ]; then
+    for i in {0..1}; do
+        IFNAME="veth${i}"
+        ip link del "$IFNAME" || true
+    done
+    ip link set "$BR" down
     brctl delbr $BR
+    exit 0
+fi
+
+
 brctl addbr $BR
 
 for i in {0..1}; do