systemctl: describe the halt/poweroff/reboot/shutdown compat commands

The custom halt_help() and shutdown_help() are replaced by COMMAND()
descriptions (one per command name, halt/poweroff/reboot sharing the
"halt" option namespace), and --introspect-cli is added to both parsers.
halt/poweroff/reboot now each reference their own man page name.

src/systemctl/systemctl-compat-halt.c

@@ -1,12 +1,10 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #include "sd-daemon.h"
+#include "sd-json.h"
 
 #include "ansi-color.h"
-#include "format-table.h"
-#include "help-util.h"
 #include "log.h"
-#include "options.h"
 #include "process-util.h"
 #include "reboot-util.h"
 #include "systemctl.h"
@@ -15,40 +13,35 @@
 #include "systemctl-start-unit.h"
 #include "systemctl-util.h"
 #include "utmp-wtmp.h"
+#include "verbs.h"
 
-static int halt_help(void) {
+COMMAND(
-        _cleanup_(table_unrefp) Table *options = NULL;
+        "halt\0",
-        int r;
+        "Halt the system.",
+        .footer = "This is a compatibility interface, please use the more powerful "
+                  "'systemctl halt' command instead.",
+        .man_pages = "halt.8\0",
+        .option_namespace = "halt",
+);
 
-        r = option_parser_get_help_table_ns("halt", &options);
+COMMAND(
-        if (r < 0)
+        "poweroff\0",
-                return r;
+        "Power off the system.",
+        .footer = "This is a compatibility interface, please use the more powerful "
+                  "'systemctl poweroff' command instead.",
+        .man_pages = "poweroff.8\0",
+        .option_namespace = "halt",
+);
 
-        /* Note: if you are tempted to add new command line switches here, please do not. Let this
+COMMAND(
-         * compatibility command rest in peace. Its interface is not even owned by us as much as it is by
+        "reboot\0",
-         * sysvinit. If you add something new, add it to "systemctl halt", "systemctl reboot", "systemctl
+        "Reboot the system.",
-         * poweroff" instead. */
+        .argspec = "[ARG]\0",
-
+        .footer = "This is a compatibility interface, please use the more powerful "
-        help_cmdline(arg_action == ACTION_REBOOT ? "[OPTIONS…] [ARG]" : "[OPTIONS…]");
+                  "'systemctl reboot' command instead.",
-        help_abstract(arg_action == ACTION_REBOOT   ? "Reboot the system." :
+        .man_pages = "reboot.8\0",
-                      arg_action == ACTION_POWEROFF ? "Power off the system." :
+        .option_namespace = "halt",
-                                                      "Halt the system.");
+);
-
-        help_section("Options");
-        r = table_print_or_warn(options);
-        if (r < 0)
-                return r;
-
-        printf("\n%sThis is a compatibility interface, please use the more powerful 'systemctl %s' command instead.%s\n",
-               ansi_highlight_red(),
-               arg_action == ACTION_REBOOT   ? "reboot" :
-               arg_action == ACTION_POWEROFF ? "poweroff" :
-                                               "halt",
-               ansi_normal());
-
-        help_man_page_reference("halt", "8");
-        return 0;
-}
 
 int halt_parse_argv(int argc, char *argv[], int log_level_shift) {
         int r;
@@ -62,13 +55,20 @@ int halt_parse_argv(int argc, char *argv[], int log_level_shift) {
                 .log_level_shift = log_level_shift,
         };
 
+        /* Note: if you are tempted to add new command line switches here, please do not. Let this
+         * compatibility command rest in peace. Its interface is not even owned by us as much as it
+         * is by sysvinit. If you add something new, add it to "systemctl halt", "systemctl
+         * reboot", "systemctl poweroff" instead. */
+
         FOREACH_OPTION_OR_RETURN(c, &opts)
                 switch (c) {
 
                 OPTION_NAMESPACE("halt"): {}
 
                 OPTION_LONG("help", NULL, "Show this help"):
-                        return halt_help();
+                        return command_print_help_full(
+                                        action_table[arg_action].verb,
+                                        /* footer_ansi_seq= */ ansi_highlight_red());
 
                 OPTION_LONG("halt", NULL, "Halt the machine"):
                         arg_action = ACTION_HALT;
@@ -108,6 +108,9 @@ int halt_parse_argv(int argc, char *argv[], int log_level_shift) {
                 OPTION_SHORT('h', NULL, /* help= */ NULL):
                         /* Compatibility nops */
                         break;
+
+                OPTION_COMMON_INTROSPECT_CLI:
+                        return introspect_cli(SD_JSON_FORMAT_OFF);
                 }
 
         char **args = option_parser_get_args(&opts);

src/systemctl/systemctl-compat-shutdown.c

@@ -1,10 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include "sd-json.h"
+
 #include "ansi-color.h"
-#include "format-table.h"
-#include "help-util.h"
 #include "log.h"
-#include "options.h"
 #include "parse-util.h"
 #include "reboot-util.h"
 #include "string-util.h"
@@ -12,35 +11,17 @@
 #include "systemctl.h"
 #include "systemctl-compat-shutdown.h"
 #include "time-util.h"
+#include "verbs.h"
 
-static int shutdown_help(void) {
+COMMAND(
-        _cleanup_(table_unrefp) Table *options = NULL;
+        "shutdown\0",
-        int r;
+        "Shut down the system.",
-
+        .argspec = "[TIME] [WALL…]\0",
-        r = option_parser_get_help_table_ns("shutdown", &options);
+        .footer = "This is a compatibility interface, please use the more powerful 'systemctl halt', "
-        if (r < 0)
+                  "'systemctl poweroff', 'systemctl reboot' commands instead.",
-                return r;
+        .man_pages = "shutdown.8\0",
-
+        .option_namespace = "shutdown",
-        /* Note: if you are tempted to add new command line switches here, please do not. Let this
+);
-         * compatibility command rest in peace. Its interface is not even owned by us as much as it is by
-         * sysvinit. If you add something new, add it to "systemctl halt", "systemctl reboot", "systemctl
-         * poweroff" instead. */
-
-        help_cmdline("[OPTIONS…] [TIME] [WALL…]");
-        help_abstract("Shut down the system.");
-
-        help_section("Options");
-        r = table_print_or_warn(options);
-        if (r < 0)
-                return r;
-
-        printf("\n%sThis is a compatibility interface, please use the more powerful 'systemctl halt',\n"
-               "'systemctl poweroff', 'systemctl reboot' commands instead.%s\n",
-               ansi_highlight_red(), ansi_normal());
-
-        help_man_page_reference("shutdown", "8");
-        return 0;
-}
 
 static int parse_shutdown_time_spec(const char *t, usec_t *ret) {
         int r;
@@ -128,13 +109,20 @@ int shutdown_parse_argv(int argc, char *argv[], int log_level_shift) {
                 .log_level_shift = log_level_shift,
         };
 
+        /* Note: if you are tempted to add new command line switches here, please do not. Let this
+         * compatibility command rest in peace. Its interface is not even owned by us as much as it
+         * is by sysvinit. If you add something new, add it to "systemctl halt", "systemctl
+         * reboot", "systemctl poweroff" instead. */
+
         FOREACH_OPTION_OR_RETURN(c, &opts)
                 switch (c) {
 
                 OPTION_NAMESPACE("shutdown"): {}
 
                 OPTION_LONG("help", NULL, "Show this help"):
-                        return shutdown_help();
+                        return command_print_help_full(
+                                        "shutdown",
+                                        /* footer_ansi_seq= */ ansi_highlight_red());
 
                 OPTION('H', "halt", NULL, "Halt the machine"):
                         arg_action = ACTION_HALT;
@@ -182,6 +170,9 @@ int shutdown_parse_argv(int argc, char *argv[], int log_level_shift) {
                 OPTION_SHORT('F', NULL,  /* help= */ NULL): {}
                 OPTION_SHORT('t', "ARG", /* help= */ NULL):
                         break;
+
+                OPTION_COMMON_INTROSPECT_CLI:
+                        return introspect_cli(SD_JSON_FORMAT_OFF);
                 }
 
         char **args = option_parser_get_args(&opts);

test/units/TEST-74-AUX-UTILS.introspect-cli.sh

@@ -18,6 +18,7 @@ INTROSPECTABLE=(
     coredumpctl
     dmi_memory_id
     fido_id
+    halt
     homectl
     hostnamectl
     importctl
@@ -30,9 +31,12 @@ INTROSPECTABLE=(
     networkctl
     oomctl
     portablectl
+    poweroff
+    reboot
     resolvectl
     run0
     scsi_id
+    shutdown
     storagectl
     systemctl
     systemd-ac-power
@@ -138,7 +142,9 @@ for i in "${INTROSPECTABLE[@]}"; do
     $i --intro | grep -e --help
 
     # If the tool has a "help" verb, it must work too
-    if $i --introspect-cli | jq -e 'any(.commands[]; (.verbs // []) | any(.names[0] == "help"))' >/dev/null; then
+    if $i --introspect-cli | jq -e --arg name "$i" \
+            'any(.commands[]; any(.names[]; . == $name) and ((.verbs // []) | any(.names[0] == "help")))' \
+             >/dev/null; then
         # 'systemctl help' shows unit manuals
         [[ "$i" == systemctl ]] && continue
 
@@ -172,3 +178,6 @@ systemd-mstack --introspect-cli | jq -e \
 
 systemd-run --introspect-cli | jq -e \
     '[.commands[].names[0]] | sort == ["run0", "systemd-run"]'
+
+systemctl --introspect-cli | jq -e \
+    '[.commands[].names[0]] | sort == ["halt", "poweroff", "reboot", "shutdown", "systemctl"]'