util-lib: add stub parser for --help, --version

src/shared/meson.build

@@ -184,6 +184,8 @@ shared_sources = files('''
         securebits-util.h
         serialize.c
         serialize.h
+        service-util.c
+        service-util.h
         sleep-config.c
         sleep-config.h
         socket-netlink.c

src/shared/service-util.c

@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <getopt.h>
+#include <stdio.h>
+
+#include "alloc-util.h"
+#include "pretty-print.h"
+#include "service-util.h"
+#include "terminal-util.h"
+#include "util.h"
+
+static int help(const char *program_path, const char *service, const char *description) {
+        _cleanup_free_ char *link = NULL;
+        int r;
+
+        r = terminal_urlify_man(service, "8", &link);
+        if (r < 0)
+                return log_oom();
+
+        printf("%s [OPTIONS...]\n\n"
+               "%s%s%s\n\n"
+               "This program takes no positional arguments.\n\n"
+               "%sOptions%s:\n"
+               "  -h --help                 Show this help\n"
+               "     --version              Show package version\n"
+               "\nSee the %s for details.\n"
+               , program_path
+               , ansi_highlight(), description, ansi_normal()
+               , ansi_underline(), ansi_normal()
+               , link
+        );
+
+        return 0; /* No further action */
+}
+
+int service_parse_argv(
+                const char *service,
+                const char *description,
+                int argc, char *argv[]) {
+
+        enum {
+                ARG_VERSION = 0x100,
+        };
+
+        static const struct option options[] = {
+                { "help",           no_argument,       NULL, 'h'                },
+                { "version",        no_argument,       NULL, ARG_VERSION        },
+                {}
+        };
+
+        int c;
+
+        assert(argc >= 0);
+        assert(argv);
+
+        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
+                switch(c) {
+
+                case 'h':
+                        return help(argv[0], service, description);
+
+                case ARG_VERSION:
+                        return version();
+
+                case '?':
+                        return -EINVAL;
+
+                default:
+                        assert_not_reached("Unknown option code.");
+                }
+
+        if (optind < argc)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                       "This program takes no arguments.");
+
+        return 1; /* Further action */
+}

src/shared/service-util.h

@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+int service_parse_argv(
+                const char *service,
+                const char *description,
+                int argc, char *argv[]);