Kernel.py: wait for thread when exiting

Wait for thread loop to return when exiting

pimdm/Kernel.py

@@ -63,9 +63,9 @@ class Kernel(metaclass=ABCMeta):
         self.to_format_mrule = "ip {ip_version} mrule {cmd} {selector} {interface_name} lookup {table_id}".format
 
         # receive signals from kernel with a background thread
-        handler_thread = Thread(target=self.handler)
-        handler_thread.daemon = True
-        handler_thread.start()
+        self.handler_thread = Thread(target=self.handler)
+        self.handler_thread.daemon = True
+        self.handler_thread.start()
 
     '''
     Structure to create/remove virtual interfaces
@@ -189,9 +189,14 @@ class Kernel(metaclass=ABCMeta):
         raise NotImplementedError
 
     @abstractmethod
-    def exit(self):
+    def close_socket(self):
         raise NotImplementedError
 
+    def exit(self):
+        self.running = False
+        self.close_socket()
+        self.handler_thread.join()
+
     @abstractmethod
     def handler(self):
         raise NotImplementedError
@@ -449,12 +454,15 @@ class Kernel4(Kernel):
         if len(self.routing[kernel_entry.source_ip]) == 0:
             self.routing.pop(kernel_entry.source_ip)
 
-    def exit(self):
-        self.running = False
+    def close_socket(self):
+        with socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_IGMP) as s:
+            s.sendto(b'', ('', 0))
+        self.socket.close()
 
+    def exit(self):
         # MRT DONE
         self.socket.setsockopt(socket.IPPROTO_IP, self.MRT_DONE, 1)
-        self.socket.close()
+        super().exit()
 
 
     '''
@@ -695,12 +703,15 @@ class Kernel6(Kernel):
         if len(self.routing[kernel_entry.source_ip]) == 0:
             self.routing.pop(kernel_entry.source_ip)
 
-    def exit(self):
-        self.running = False
+    def close_socket(self):
+        with socket.socket(socket.AF_INET6, socket.SOCK_RAW, socket.IPPROTO_ICMPV6) as s:
+            s.sendto(b'0000', ('', 0))
+        self.socket.close()
 
+    def exit(self):
         # MRT DONE
         self.socket.setsockopt(socket.IPPROTO_IPV6, self.MRT6_DONE, 1)
-        self.socket.close()
+        super().exit()
 
     '''
     /*

pimdm/Run.py

@@ -172,7 +172,7 @@ def run_config(conf_file_path):
         pim_globals.MULTICAST_TABLE_ID, pim_globals.UNICAST_TABLE_ID = Config.get_vrfs(conf_file_path)
         start(conf_file_path)
     except (ImportError, ModuleNotFoundError):
-        sys.exit("PYYAML needs to be installed. Execute \"pip3 install pyyaml\"")
+        raise Exception("PYYAML needs to be installed. Execute \"pip3 install pyyaml\"")
 
 def print_multicast_routes(args):
     if args.ipv4 or not args.ipv6:
@@ -200,22 +200,17 @@ def main():
 
     if args.start:
         start()
-        sys.exit(0)
     elif args.stop:
         client_socket(args)
-        sys.exit(0)
     elif args.config:
         run_config(os.path.abspath(args.config[0]))
     elif args.verbose:
         os.system("tail -f {}".format(PROCESS_LOG_STDOUT_FILE.format(pim_globals.MULTICAST_TABLE_ID)))
-        sys.exit(0)
     elif args.multicast_routes:
         print_multicast_routes(args)
-        sys.exit(0)
     elif not is_running():
         print("PIM-DM is not running")
         parser.print_usage()
-        sys.exit(0)
 
     client_socket(args)