util/ectool: Handle arguments more carefully

Check if an argument is given and if not print the usage.
Check if all arguments are handled by getopt and if not print the usage.

Change-Id: I40dbd2a51d018eb549e9b2fa4365b3e4f9355bff
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/27778
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Alexander Couzens <lynxis@fe80.eu>
Reviewed-by: Evgeny Zinoviev <me@ch1p.com>

util/ectool/ectool.c

@@ -90,6 +90,11 @@ int main(int argc, char *argv[])
 		{0, 0, 0, 0}
 	};
 
+	if (argv[1] == NULL) {
+		print_usage(argv[0]);
+		exit(1);
+	}
+
 	while ((opt = getopt_long(argc, argv, "vh?Vidqpw:z:",
 				  long_options, &option_index)) != EOF) {
 		switch (opt) {
@@ -128,6 +133,12 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	if (optind < argc) {
+		fprintf(stderr, "Error: Extra parameter found.\n");
+		print_usage(argv[0]);
+		exit(1);
+	}
+
 	if (get_ports && get_ec_ports() != 0)
 		fprintf(stderr, "Cannot get EC ports from /proc/ioports, "
 				"fallback to default.");