systemctl,loginctl,machinectl: use a shared helper for arg_signal

I seems frivolous to yet another two -util.[ch] files, but the helper
should be in shared/ and it doesn't seem to fit anywhere else.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/shared/parse-argument.h b/src/shared/parse-argument.h
new file mode 100644
index 0000000000..7a5419174d
--- /dev/null
+++ b/src/shared/parse-argument.h
@@ -0,0 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+int parse_signal_argument(const char *s, int *ret);