commands: time: switch to using getopt for -n

Now that we have support for the stop-at-first-non-option scanning mode
indicated by a leading `+', there is nothing preventing us from using
getopt for the time command. This rids us of interleaving argument
parsing with the command's processing, has the command behave as one
would expect, e.g. if multiple -n arguments are specified and allows for
easier future extension.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Link: https://lore.barebox.org/20240304190038.3486881-47-a.fatoum@pengutronix.de
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 18 insertions, 10 deletions

diff --git a/commands/time.c b/commands/time.c
index 5b8933ea65..72647a3bb8 100644
--- a/commands/time.c
+++ b/commands/time.c
@@ -5,30 +5,38 @@
 #include <clock.h>
 #include <linux/math64.h>
 #include <malloc.h>
+#include <getopt.h>
 
 static int do_time(int argc, char *argv[])
 {
-	int i;
+	int i, opt;
 	unsigned char *buf;
 	u64 start, end, diff64;
 	bool nanoseconds = false;
 	int len = 1; /* '\0' */
 
-	if (argc < 2)
+	while ((opt = getopt(argc, argv, "+n")) > 0) {
+		switch (opt) {
+		case 'n':
+			nanoseconds = true;
+			break;
+		default:
+			return COMMAND_ERROR_USAGE;
+		}
+	}
+
+	argv += optind;
+	argc -= optind;
+
+	if (argc < 1)
 		return COMMAND_ERROR_USAGE;
 
-	for (i = 1; i < argc; i++)
+	for (i = 0; i < argc; i++)
 		len += strlen(argv[i]) + 1;
 
 	buf = xzalloc(len);
 
-	i = 1;
-	if (!strcmp(argv[i], "-n")) {
-		nanoseconds = true;
-		i++;
-	}
-
-	for (; i < argc; i++) {
+	for (i = 0; i < argc; i++) {
 		strcat(buf, argv[i]);
 		strcat(buf, " ");
 	}