more explicit daemonization

bin/key-mapper-control

@@ -152,19 +152,18 @@ def internals(options):
 
     key-mapper-control should be started with sudo or pkexec for this.
     """
+    debug = ' -d' if options.debug else ''
+
     if options.command == HELPER:
-        cmd = ['key-mapper-helper']
+        cmd = f'key-mapper-helper{debug}'
     elif options.command == START_DAEMON:
-        cmd = ['key-mapper-service', '--hide-info']
+        cmd = f'key-mapper-service --hide-info{debug}'
     else:
         return
 
-    if options.debug:
-        cmd.append('-d')
-
-    # Popen makes os.system of the main process continue with stuff while
-    # cmd runs in the background.
-    subprocess.Popen(cmd)
+    # daemonize
+    cmd = f'{cmd} &'
+    os.system(cmd)
 
 
 if __name__ == '__main__':

keymapper/daemon.py

@@ -198,9 +198,8 @@ class Daemon:
             # Blocks until pkexec is done asking for the password.
             # Runs via key-mapper-control so that auth_admin_keep works
             # for all pkexec calls of the gui
-            cmd = 'pkexec key-mapper-control --command start-daemon'
-            if is_debug():
-                cmd += ' -d'
+            debug = ' -d' if is_debug() else ''
+            cmd = f'pkexec key-mapper-control --command start-daemon {debug}'
 
             # using pkexec will also cause the service to continue running in
             # the background after the gui has been closed, which will keep

keymapper/gui/window.py

@@ -111,6 +111,8 @@ class Window:
     def __init__(self):
         self.dbus = None
 
+        self.start_processes()
+
         self.selected_device = None
         self.selected_preset = None
 
@@ -130,8 +132,6 @@ class Window:
         builder.connect_signals(self)
         self.builder = builder
 
-        self.start_processes()
-
         self.confirm_delete = builder.get_object('confirm-delete')
         self.about = builder.get_object('about-dialog')
         self.about.connect('delete-event', on_close_about)
@@ -169,21 +169,20 @@ class Window:
         self.ctrl = False
         self.unreleased_warn = 0
 
+        if not is_helper_running():
+            self.show_status(CTX_ERROR, 'The helper did not start')
+
     def start_processes(self):
         """Start helper and daemon via pkexec to run in the background."""
         # this function is overwritten in tests
         self.dbus = Daemon.connect()
 
-        cmd = 'pkexec key-mapper-control --command helper'
-        if is_debug:
-            cmd += ' -d'
+        debug = ' -d' if is_debug() else ''
+        cmd = f'pkexec key-mapper-control --command helper {debug}'
 
         logger.debug('Running `%s`', cmd)
         os.system(cmd)
 
-        if not is_helper_running():
-            self.show_status(CTX_ERROR, 'The helper did not start')
-
     def show_confirm_delete(self):
         """Blocks until the user decided about an action."""
         text = f'Are you sure to delete preset "{self.selected_preset}"?'

tests/testcases/test_control.py

@@ -249,17 +249,17 @@ class TestControl(unittest.TestCase):
         self.assertEqual(config.get('foo'), 'bar')
 
     def test_internals(self):
-        with mock.patch('subprocess.Popen') as popen_patch:
+        with mock.patch('os.system') as os_system_patch:
             internals(options('helper', None, None, None, False, False, False))
-            popen_patch.assert_called_once()
-            self.assertIn('key-mapper-helper', popen_patch.call_args.args[0])
-            self.assertNotIn('-d', popen_patch.call_args.args[0])
+            os_system_patch.assert_called_once()
+            self.assertIn('key-mapper-helper', os_system_patch.call_args.args[0])
+            self.assertNotIn('-d', os_system_patch.call_args.args[0])
 
-        with mock.patch('subprocess.Popen') as popen_patch:
+        with mock.patch('os.system') as os_system_patch:
             internals(options('start-daemon', None, None, None, False, False, True))
-            popen_patch.assert_called_once()
-            self.assertIn('key-mapper-service', popen_patch.call_args.args[0])
-            self.assertIn('-d', popen_patch.call_args.args[0])
+            os_system_patch.assert_called_once()
+            self.assertIn('key-mapper-service', os_system_patch.call_args.args[0])
+            self.assertIn('-d', os_system_patch.call_args.args[0])
 
 
 if __name__ == "__main__":