Merge pull request #2364 from vyos/mergify/bp/sagitta/pr-2361

pmacct: T5232: Fixed pmacct service control via systemctl (backport #2361)

1 files changed, 67 insertions, 0 deletions

diff --git a/src/system/uacctd_stop.py b/src/system/uacctd_stop.py
new file mode 100755
index 000000000..7fbac0566
--- /dev/null
+++ b/src/system/uacctd_stop.py
@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2023 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Control pmacct daemons in a tricky way.
+# Pmacct has signal processing in a main loop, together with packet
+# processing. Because of this, while it is waiting for packets, it cannot
+# handle the control signal. We need to start the systemctl command and then
+# send some packets to pmacct to wake it up
+
+from argparse import ArgumentParser
+from socket import socket
+from sys import exit
+from time import sleep
+
+from psutil import Process
+
+
+def stop_process(pid: int, timeout: int) -> None:
+    """Send a signal to uacctd
+    and then send packets to special address predefined in a firewall
+    to unlock main loop in uacctd and finish the process properly
+
+    Args:
+        pid (int): uacctd PID
+        timeout (int): seconds to wait for a process end
+    """
+    # find a process
+    uacctd = Process(pid)
+    uacctd.terminate()
+
+    # create a socket
+    trigger = socket()
+
+    first_cycle: bool = True
+    while uacctd.is_running() and timeout:
+        trigger.sendto(b'WAKEUP', ('127.0.254.0', 0))
+        # do not sleep during first attempt
+        if not first_cycle:
+            sleep(1)
+            timeout -= 1
+        first_cycle = False
+
+
+if __name__ == '__main__':
+    parser = ArgumentParser()
+    parser.add_argument('process_id',
+                        type=int,
+                        help='PID file of uacctd core process')
+    parser.add_argument('timeout',
+                        type=int,
+                        help='time to wait for process end')
+    args = parser.parse_args()
+    stop_process(args.process_id, args.timeout)
+    exit()