checking inf down to be delete

ubuntu_base/if_utils.py

@@ -49,6 +49,25 @@ def add_interface_to_bridge(bridge_name, interface_name):
     subprocess.run(["sudo", "brctl", "addif", bridge_name, interface_name], check=True)
 
 
+def is_interface_down(interface):
+    """
+    Check if the network interface is down.
+    :param interface: Name of the network interface to check
+    :return: True if the interface is down, False otherwise
+    """
+    try:
+        result = subprocess.run(
+            ["ip", "link", "show", interface],
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            text=True
+        )
+        return "state DOWN" in result.stdout
+    except subprocess.CalledProcessError:
+        print(f"Failed to check status of interface {interface}.")
+        return False
+
+
 def delete_tuntap_interface(interface_name):
     """
     Delete a tuntap mode tap interface.
@@ -58,6 +77,10 @@ def delete_tuntap_interface(interface_name):
     subprocess.run(["sudo", "ip", "link", "set", "dev", interface_name, "down"], check=True)
 
     # Delete the tuntap interface
+    print("Waiting for interface to be down...")
+    while not is_interface_down(interface_name):
+        pass
+    
     subprocess.run(["sudo", "ip", "tuntap", "del", interface_name, "mode", "tap"], check=True)