cgtop: convert to VERB_COMMAND and add --introspect-cli

The custom help() is replaced by a COMMAND() description, and
--introspect-cli is added.

src/cgtop/cgtop.c

@@ -3,28 +3,29 @@
 #include <signal.h>
 #include <unistd.h>
 
+#include "sd-json.h"
+
 #include "alloc-util.h"
+#include "ansi-color.h"
 #include "build.h"
 #include "cgroup-show.h"
 #include "cgroup-util.h"
 #include "cpu-set-util.h"
 #include "fd-util.h"
 #include "fileio.h"
-#include "format-table.h"
 #include "hashmap.h"
 #include "log.h"
 #include "main-func.h"
-#include "options.h"
 #include "parse-argument.h"
 #include "parse-util.h"
 #include "path-util.h"
-#include "pretty-print.h"
 #include "process-util.h"
 #include "procfs-util.h"
 #include "sort-util.h"
 #include "string-table.h"
 #include "terminal-util.h"
 #include "time-util.h"
+#include "verbs.h"
 #include "virt.h"
 
 typedef struct Group {
@@ -89,6 +90,13 @@ static PidsCount arg_count = COUNT_PIDS;
 static Order arg_order = ORDER_CPU;
 static CPUType arg_cpu_type = CPU_PERCENTAGE;
 
+COMMAND(
+        "systemd-cgtop\0",
+        "Show top control groups by their resource usage.",
+        .argspec = "[CGROUP]\0",
+        .man_pages = "systemd-cgtop.1\0",
+);
+
 static const char *order_table[_ORDER_MAX] = {
         [ORDER_PATH]   = "path",
         [ORDER_TASKS]  = "tasks",
@@ -684,33 +692,6 @@ static void display(Hashmap *a) {
         }
 }
 
-static int help(void) {
-        _cleanup_free_ char *link = NULL;
-        _cleanup_(table_unrefp) Table *options = NULL;
-        int r;
-
-        r = terminal_urlify_man("systemd-cgtop", "1", &link);
-        if (r < 0)
-                return log_oom();
-
-        r = option_parser_get_help_table(&options);
-        if (r < 0)
-                return r;
-
-        printf("%s [OPTIONS...] [CGROUP]\n\n"
-               "%sShow top control groups by their resource usage.%s\n\n",
-               program_invocation_short_name,
-               ansi_highlight(),
-               ansi_normal());
-
-        r = table_print_or_warn(options);
-        if (r < 0)
-                return r;
-
-        printf("\nSee the %s for details.\n", link);
-        return 0;
-}
-
 static int parse_argv(int argc, char *argv[]) {
         assert(argc >= 1);
         assert(argv);
@@ -722,7 +703,7 @@ static int parse_argv(int argc, char *argv[]) {
                 switch (c) {
 
                 OPTION_COMMON_HELP:
-                        return help();
+                        return command_print_help("systemd-cgtop");
 
                 OPTION_COMMON_VERSION:
                         return version();
@@ -822,6 +803,9 @@ static int parse_argv(int argc, char *argv[]) {
                 OPTION_COMMON_MACHINE:
                         arg_machine = opts.arg;
                         break;
+
+                OPTION_COMMON_INTROSPECT_CLI:
+                        return introspect_cli(SD_JSON_FORMAT_OFF);
                 }
 
         size_t n_args = option_parser_get_n_args(&opts);

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

@@ -20,6 +20,7 @@ INTROSPECTABLE=(
     systemd-bsod
     systemd-cat
     systemd-cgls
+    systemd-cgtop
     systemd-dissect
     systemd-firstboot
     systemd-hwdb