udevadm-info: use common verb help and add --introspect-cli

The arg_no_pager variable is lifted to udevadm, so that it can be
referenced in the command structure. It's only used for 'udevadm info',
but that's OK. We can later generalize it if wanted.

The custom help() is replaced by the common verb help, which derives the
synopsis, abstract, and option list from the verb declaration in udevadm.c
and the "udevadm-info" option namespace. --help now goes through the
pager, like other commands with --no-pager.

src/udev/udevadm-info.c

@@ -19,9 +19,7 @@
 #include "errno-util.h"
 #include "fd-util.h"
 #include "fileio.h"
-#include "format-table.h"
 #include "glyph-util.h"
-#include "help-util.h"
 #include "options.h"
 #include "pager.h"
 #include "parse-argument.h"
@@ -34,6 +32,7 @@
 #include "udev-util.h"
 #include "udevadm.h"
 #include "udevadm-util.h"
+#include "verbs.h"
 
 typedef enum ActionType {
         ACTION_QUERY,
@@ -60,7 +59,6 @@ static bool arg_export = false;
 static bool arg_value = false;
 static const char *arg_export_prefix = NULL;
 static usec_t arg_wait_for_initialization_timeout = 0;
-static PagerFlags arg_pager_flags = 0;
 static sd_json_format_flags_t arg_json_format_flags = SD_JSON_FORMAT_OFF;
 static ActionType arg_action_type = ACTION_QUERY;
 static QueryType arg_query = QUERY_ALL;
@@ -806,25 +804,6 @@ static int query_device(QueryType query, sd_device* device) {
         }
 }
 
-static int help(void) {
-        _cleanup_(table_unrefp) Table *options = NULL;
-        int r;
-
-        r = option_parser_get_help_table_ns("udevadm-info", &options);
-        if (r < 0)
-                return r;
-
-        help_cmdline("info [OPTIONS] [DEVPATH|FILE]");
-        help_abstract("Query sysfs or the udev database.");
-        help_section("Options");
-        r = table_print_or_warn(options);
-        if (r < 0)
-                return r;
-
-        help_man_page_reference("udevadm", "8");
-        return 0;
-}
-
 static int draw_tree(
                 sd_device *parent,
                 sd_device *const array[], size_t n,
@@ -996,7 +975,7 @@ static int parse_argv(int argc, char *argv[]) {
                 OPTION_NAMESPACE("udevadm-info"): {}
 
                 OPTION_COMMON_HELP:
-                        return help();
+                        return command_print_verb_help("info");
 
                 OPTION('V', "version", NULL, "Show package version"):
                         return print_version();
@@ -1179,6 +1158,9 @@ static int parse_argv(int argc, char *argv[]) {
                             "Query devices that are not initialized yet"):
                         arg_initialized_match = MATCH_INITIALIZED_NO;
                         break;
+
+                OPTION_COMMON_INTROSPECT_CLI:
+                        return introspect_cli(arg_json_format_flags);
                 }
 
         r = strv_extend_strv(&arg_devices, option_parser_get_args(&opts), /* filter_duplicates= */ false);

src/udev/udevadm.c

@@ -9,17 +9,21 @@
 #include "label-util.h"
 #include "main-func.h"
 #include "options.h"
+#include "pager.h"
 #include "udev-util.h"
 #include "udevadm.h"
 #include "udevd.h"
 #include "verbs.h"
 
+PagerFlags arg_pager_flags = 0;
+
 COMMAND(
         "udevadm\0",
         "Send control commands or test the device manager.",
         .argspec = "COMMAND [COMMAND OPTION…]\0",
         .man_pages = "udevadm(8)\0",
         .option_namespace = "udevadm",
+        .pager_flags = &arg_pager_flags,
 );
 
 /* All verbs are defined here, right after the COMMAND, so that they are attributed to it. Each

src/udev/udevadm.h

@@ -3,6 +3,8 @@
 
 #include "forward.h"
 
+extern PagerFlags arg_pager_flags;
+
 int verb_cat_main(int argc, char *argv[], uintptr_t _data, void *userdata);
 int verb_info_main(int argc, char *argv[], uintptr_t _data, void *userdata);
 int verb_trigger_main(int argc, char *argv[], uintptr_t _data, void *userdata);