Unify parse_argv style

getopt is usually good at printing out a nice error message when
commandline options are invalid. It distinguishes between an unknown
option and a known option with a missing arg. It is better to let it
do its job and not use opterr=0 unless we actually want to suppress
messages. So remove opterr=0 in the few places where it wasn't really
useful.

When an error in options is encountered, we should not print a lengthy
help() and overwhelm the user, when we know precisely what is wrong
with the commandline. In addition, since help() prints to stdout, it
should not be used except when requested with -h or --help.

Also, simplify things here and there.

1 files changed, 22 insertions, 35 deletions

diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index 8ec0db2b2d..daf7e31de9 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -5432,7 +5432,7 @@ static int is_system_running(sd_bus *bus, char **args) {
         return streq(state, "running") ? EXIT_SUCCESS : EXIT_FAILURE;
 }
 
-static int systemctl_help(void) {
+static void systemctl_help(void) {
 
         pager_open_if_enabled();
 
@@ -5557,12 +5557,9 @@ static int systemctl_help(void) {
                "  hibernate                       Hibernate the system\n"
                "  hybrid-sleep                    Hibernate and suspend the system\n",
                program_invocation_short_name);
-
-        return 0;
 }
 
-static int halt_help(void) {
-
+static void halt_help(void) {
         printf("%s [OPTIONS...]%s\n\n"
                "%s the system.\n\n"
                "     --help      Show this help\n"
@@ -5578,12 +5575,9 @@ static int halt_help(void) {
                arg_action == ACTION_REBOOT   ? "Reboot" :
                arg_action == ACTION_POWEROFF ? "Power off" :
                                                "Halt");
-
-        return 0;
 }
 
-static int shutdown_help(void) {
-
+static void shutdown_help(void) {
         printf("%s [OPTIONS...] [TIME] [WALL...]\n\n"
                "Shut down the system.\n\n"
                "     --help      Show this help\n"
@@ -5595,12 +5589,9 @@ static int shutdown_help(void) {
                "     --no-wall   Don't send wall message before halt/power-off/reboot\n"
                "  -c             Cancel a pending shutdown\n",
                program_invocation_short_name);
-
-        return 0;
 }
 
-static int telinit_help(void) {
-
+static void telinit_help(void) {
         printf("%s [OPTIONS...] {COMMAND}\n\n"
                "Send control commands to the init daemon.\n\n"
                "     --help      Show this help\n"
@@ -5613,18 +5604,13 @@ static int telinit_help(void) {
                "  q, Q           Reload init daemon configuration\n"
                "  u, U           Reexecute init daemon\n",
                program_invocation_short_name);
-
-        return 0;
 }
 
-static int runlevel_help(void) {
-
+static void runlevel_help(void) {
         printf("%s [OPTIONS...]\n\n"
                "Prints the previous and current runlevel of the init system.\n\n"
                "     --help      Show this help\n",
                program_invocation_short_name);
-
-        return 0;
 }
 
 static void help_types(void) {
@@ -5719,12 +5705,13 @@ static int systemctl_parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "ht:p:alqfs:H:M:n:o:ir", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "ht:p:alqfs:H:M:n:o:ir", options, NULL)) >= 0)
 
                 switch (c) {
 
                 case 'h':
-                        return systemctl_help();
+                        systemctl_help();
+                        return 0;
 
                 case ARG_VERSION:
                         puts(PACKAGE_STRING);
@@ -5992,7 +5979,6 @@ static int systemctl_parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (arg_transport != BUS_TRANSPORT_LOCAL && arg_scope != UNIT_FILE_SYSTEM) {
                 log_error("Cannot access user instance remotely.");
@@ -6032,11 +6018,12 @@ static int halt_parse_argv(int argc, char *argv[]) {
                 if (runlevel == '0' || runlevel == '6')
                         arg_force = 2;
 
-        while ((c = getopt_long(argc, argv, "pfwdnih", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "pfwdnih", options, NULL)) >= 0)
                 switch (c) {
 
                 case ARG_HELP:
-                        return halt_help();
+                        halt_help();
+                        return 0;
 
                 case ARG_HALT:
                         arg_action = ACTION_HALT;
@@ -6079,7 +6066,6 @@ static int halt_parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (arg_action == ACTION_REBOOT && (argc == optind || argc == optind + 1)) {
                 r = update_reboot_param_file(argc == optind + 1 ? argv[optind] : NULL);
@@ -6164,11 +6150,12 @@ static int shutdown_parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "HPrhkt:afFc", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "HPrhkt:afFc", options, NULL)) >= 0)
                 switch (c) {
 
                 case ARG_HELP:
-                        return shutdown_help();
+                        shutdown_help();
+                        return 0;
 
                 case 'H':
                         arg_action = ACTION_HALT;
@@ -6217,7 +6204,6 @@ static int shutdown_parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (argc > optind && arg_action != ACTION_CANCEL_SHUTDOWN) {
                 r = parse_time_spec(argv[optind], &arg_when);
@@ -6278,11 +6264,12 @@ static int telinit_parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "", options, NULL)) >= 0)
                 switch (c) {
 
                 case ARG_HELP:
-                        return telinit_help();
+                        telinit_help();
+                        return 0;
 
                 case ARG_NO_WALL:
                         arg_no_wall = true;
@@ -6294,10 +6281,10 @@ static int telinit_parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (optind >= argc) {
-                telinit_help();
+                log_error("%s: required argument missing.",
+                          program_invocation_short_name);
                 return -EINVAL;
         }
 
@@ -6343,11 +6330,12 @@ static int runlevel_parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
 
-        while ((c = getopt_long(argc, argv, "", options, NULL)) >= 0) {
+        while ((c = getopt_long(argc, argv, "", options, NULL)) >= 0)
                 switch (c) {
 
                 case ARG_HELP:
-                        return runlevel_help();
+                        runlevel_help();
+                        return 0;
 
                 case '?':
                         return -EINVAL;
@@ -6355,7 +6343,6 @@ static int runlevel_parse_argv(int argc, char *argv[]) {
                 default:
                         assert_not_reached("Unhandled option");
                 }
-        }
 
         if (optind < argc) {
                 log_error("Too many arguments.");