Centralize/unify version string printing

Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>

3 files changed, 42 insertions, 1 deletions

diff --git a/lib/Makemodule.am b/lib/Makemodule.am
index b8a1c17..8a5ee8e 100644
--- a/lib/Makemodule.am
+++ b/lib/Makemodule.am
@@ -3,7 +3,8 @@ HEADRS = lib/include/util.h lib/include/service.h lib/include/telinit.h
 libinit_a_SOURCES = lib/util/delsvc.c lib/util/svcmap.c lib/util/enum_by_name.c
 libinit_a_SOURCES += lib/util/rdsvc.c lib/util/svcscan.c lib/util/mksock.c
 libinit_a_SOURCES += lib/util/del_svc_list.c lib/util/svc_tsort.c
-libinit_a_SOURCES += lib/util/opensock.c lib/util/enum_to_name.c $(HEADRS)
+libinit_a_SOURCES += lib/util/opensock.c lib/util/enum_to_name.c
+libinit_a_SOURCES += lib/util/print_version.c $(HEADRS)
 libinit_a_CPPFLAGS = $(AM_CPPFLAGS)
 libinit_a_CFLAGS = $(AM_CFLAGS)
 
diff --git a/lib/include/util.h b/lib/include/util.h
index 18133a8..6d2bf5d 100644
--- a/lib/include/util.h
+++ b/lib/include/util.h
@@ -70,5 +70,8 @@ const char *enum_to_name(const enum_map_t *map, int value);
 */
 int mksock(const char *path, int flags);
 
+/* print a default version info and license string */
+NORETURN void print_version(const char *program);
+
 #endif /* UTIL_H */
 
diff --git a/lib/util/print_version.c b/lib/util/print_version.c
new file mode 100644
index 0000000..cda2742
--- /dev/null
+++ b/lib/util/print_version.c
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * Copyright (C) 2018 - David Oberhollenzer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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 <https://www.gnu.org/licenses/>.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+
+#include "config.h"
+#include "util.h"
+
+#define GPL_URL "https://gnu.org/licenses/gpl.html"
+
+static const char *version_string =
+"%s (pygos init) " PACKAGE_VERSION "\n"
+"Copyright (C) 2018 David Oberhollenzer\n\n"
+"License GPLv3+: GNU GPL version 3 or later <" GPL_URL ">.\n"
+"This is free software: you are free to change and redistribute it.\n"
+"There is NO WARRANTY, to the extent permitted by law.\n";
+
+void print_version(const char *program)
+{
+	fprintf(stdout, version_string, program);
+	exit(EXIT_SUCCESS);
+}