systemd-storage-fs: convert to VERB_COMMAND and add --introspect-cli

The custom help() is replaced by a COMMAND() description, and
--introspect-cli is added. The abstract is changed from the noun phrase
"Simple file system backed storage provider" to the imperative "Expose
regular files and directories as storage volumes.", following the man
page and consistent with the other commands.

src/storage/storage-fs.c

@@ -18,14 +18,11 @@
 #include "device-util.h"
 #include "errno-util.h"
 #include "fd-util.h"
-#include "format-table.h"
 #include "fs-util.h"
 #include "hashmap.h"
-#include "help-util.h"
 #include "log.h"
 #include "main-func.h"
 #include "mount-util.h"
-#include "options.h"
 #include "path-lookup.h"
 #include "path-util.h"
 #include "recurse-dir.h"
@@ -37,9 +34,16 @@
 #include "uid-classification.h"
 #include "varlink-io.systemd.StorageProvider.h"
 #include "varlink-util.h"
+#include "verbs.h"
 
 static RuntimeScope arg_runtime_scope = RUNTIME_SCOPE_SYSTEM;
 
+COMMAND(
+        "systemd-storage-fs\0",
+        "Expose regular files and directories as storage volumes.",
+        .man_pages = "systemd-storage-fs.8\0",
+);
+
 /* For now we maintain a simple, compiled-in list of templates. One of those days we might want to move these
  * into configurable drop-in files on disk. */
 typedef enum Template {
@@ -742,27 +746,6 @@ static int vl_server(void) {
         return 0;
 }
 
-static int help(void) {
-        int r;
-
-        help_cmdline("[OPTIONS...]");
-        help_abstract("Simple file system backed storage provider");
-
-        _cleanup_(table_unrefp) Table *options = NULL;
-        r = option_parser_get_help_table(&options);
-        if (r < 0)
-                return r;
-
-        help_section("Options");
-
-        r = table_print_or_warn(options);
-        if (r < 0)
-                return r;
-
-        help_man_page_reference("systemd-storage-fs", "8");
-        return 0;
-}
-
 static int parse_argv(int argc, char *argv[]) {
         assert(argc >= 0);
         assert(argv);
@@ -772,7 +755,7 @@ static int parse_argv(int argc, char *argv[]) {
                 switch (c) {
 
                 OPTION_COMMON_HELP:
-                        return help();
+                        return command_print_help("systemd-storage-fs");
 
                 OPTION_COMMON_VERSION:
                         return version();
@@ -784,6 +767,9 @@ static int parse_argv(int argc, char *argv[]) {
                 OPTION_COMMON_USER:
                         arg_runtime_scope = RUNTIME_SCOPE_USER;
                         break;
+
+                OPTION_COMMON_INTROSPECT_CLI:
+                        return introspect_cli(SD_JSON_FORMAT_OFF);
                 }
 
         if (option_parser_get_n_args(&opts) > 0)

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

@@ -52,6 +52,7 @@ INTROSPECTABLE=(
     systemd-socket-proxyd
     systemd-stdio-bridge
     systemd-storage-block
+    systemd-storage-fs
     systemd-tty-ask-password-agent
     systemd-veritysetup
     timedatectl