From: Masatake YAMATO <yamato@redhat.com>
Date: Wed, 12 Jul 2023 15:14:10 +0000 (+0900)
Subject: lsfd: introduce -H, --list-columns option for making help messages short
X-Git-Tag: v2.40-rc1~329^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e0cdf606b61a4dea385f59b382d5ff8d8b81b986;p=thirdparty%2Futil-linux.git

lsfd: introduce -H, --list-columns option for making help messages short

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
---

diff --git a/misc-utils/lsfd.1.adoc b/misc-utils/lsfd.1.adoc
index 0f866f4cc2..b2a6aa5322 100644
--- a/misc-utils/lsfd.1.adoc
+++ b/misc-utils/lsfd.1.adoc
@@ -110,6 +110,9 @@ only for *lsfd* developers.
 *--dump-counters*::
 Dump the definition of counters used in *--summary* output.
 
+*-H*, *--list-columns*::
+List available columns that you can specify at *--output* option.
+
 include::man-common/help-version.adoc[]
 
 == OUTPUT COLUMNS
diff --git a/misc-utils/lsfd.c b/misc-utils/lsfd.c
index 4c19f7e499..49f5863e07 100644
--- a/misc-utils/lsfd.c
+++ b/misc-utils/lsfd.c
@@ -1578,10 +1578,23 @@ static void collect_processes(struct lsfd_control *ctl, const pid_t pids[], int
 	ul_unref_path(pc);
 }
 
+static void __attribute__((__noreturn__)) list_colunms(FILE *out)
+{
+	fprintf(out, USAGE_COLUMNS);
+	for (size_t i = 0; i < ARRAY_SIZE(infos); i++)
+		fprintf(out, " %20s  %-10s%s\n", infos[i].name,
+			infos[i].json_type == SCOLS_JSON_STRING?  "<string>":
+			infos[i].json_type == SCOLS_JSON_ARRAY_STRING?  "<string>":
+			infos[i].json_type == SCOLS_JSON_ARRAY_NUMBER?  "<string>":
+			infos[i].json_type == SCOLS_JSON_NUMBER?  "<number>":
+			"<boolean>",
+			_(infos[i].help));
+	exit(EXIT_SUCCESS);
+}
+
 static void __attribute__((__noreturn__)) usage(void)
 {
 	FILE *out = stdout;
-	size_t i;
 
 	fputs(USAGE_HEADER, out);
 	fprintf(out, _(" %s [options]\n"), program_invocation_short_name);
@@ -1602,19 +1615,9 @@ static void __attribute__((__noreturn__)) usage(void)
 	fputs(_("     --summary[=<when>]       print summary information (only, append, or never)\n"), out);
 
 	fputs(USAGE_SEPARATOR, out);
+	fputs(_(" -H, --list-columns           list the available columns\n"), out);
 	fprintf(out, USAGE_HELP_OPTIONS(30));
 
-	fprintf(out, USAGE_COLUMNS);
-
-	for (i = 0; i < ARRAY_SIZE(infos); i++)
-		fprintf(out, " %16s  %-10s%s\n", infos[i].name,
-			infos[i].json_type == SCOLS_JSON_STRING?  "<string>":
-			infos[i].json_type == SCOLS_JSON_ARRAY_STRING?  "<string>":
-			infos[i].json_type == SCOLS_JSON_ARRAY_NUMBER?  "<string>":
-			infos[i].json_type == SCOLS_JSON_NUMBER?  "<number>":
-			"<boolean>",
-			_(infos[i].help));
-
 	fprintf(out, USAGE_MAN_TAIL("lsfd(1)"));
 
 	exit(EXIT_SUCCESS);
@@ -1926,6 +1929,7 @@ int main(int argc, char *argv[])
 		{ "summary",    optional_argument, NULL,  OPT_SUMMARY },
 		{ "counter",    required_argument, NULL, 'C' },
 		{ "dump-counters",no_argument, NULL, OPT_DUMP_COUNTERS },
+		{ "list-columns",no_argument, NULL, 'H' },
 		{ NULL, 0, NULL, 0 },
 	};
 
@@ -1934,7 +1938,7 @@ int main(int argc, char *argv[])
 	textdomain(PACKAGE);
 	close_stdout_atexit();
 
-	while ((c = getopt_long(argc, argv, "no:JrVhluQ:p:i::C:s", longopts, NULL)) != -1) {
+	while ((c = getopt_long(argc, argv, "no:JrVhluQ:p:i::C:sH", longopts, NULL)) != -1) {
 		switch (c) {
 		case 'n':
 			ctl.noheadings = 1;
@@ -2006,6 +2010,8 @@ int main(int argc, char *argv[])
 			print_version(EXIT_SUCCESS);
 		case 'h':
 			usage();
+		case 'H':
+			list_colunms(stdout);
 		default:
 			errtryhelp(EXIT_FAILURE);
 		}