[PATCH v9 1/7] sign-file: use getopt_long_only for parsing input args

[Shreenidhi Shedi <yesshedi@gmail.com>]

- getopt_long_only gives an option to use long names for options, so
  using it here to make the app usage easier.

- Use more easy to remember command line argument names

- Introduce cmd_opts structure to ease the handling of command line args

Signed-off-by: Shreenidhi Shedi <yesshedi@gmail.com>
---
 scripts/sign-file.c | 97 ++++++++++++++++++++++++++++++++++++---------
 1 file changed, 78 insertions(+), 19 deletions(-)

diff --git a/scripts/sign-file.c b/scripts/sign-file.c
index 598ef5465f82..94228865b6cc 100644
--- a/scripts/sign-file.c
+++ b/scripts/sign-file.c
@@ -213,15 +213,77 @@ static X509 *read_x509(const char *x509_name)
 	return x509;
 }
 
+struct cmd_opts {
+	char *raw_sig_name;
+	bool save_sig;
+	bool replace_orig;
+	bool raw_sig;
+	bool sign_only;
+#ifndef USE_PKCS7
+	unsigned int use_keyid;
+#endif
+};
+
+static void parse_args(int argc, char **argv, struct cmd_opts *opts)
+{
+	struct option cmd_options[] = {
+		{"rawsig",	required_argument,  0,	's'},
+		{"savesig",	no_argument,	    0,	'p'},
+		{"signonly",	no_argument,	    0,	'd'},
+#ifndef USE_PKCS7
+		{"usekeyid",	no_argument,	    0,	'k'},
+#endif
+		{0, 0, 0, 0}
+	};
+
+	int opt;
+	int opt_index = 0;
+
+	do {
+#ifndef USE_PKCS7
+		opt = getopt_long_only(argc, argv, "pds:",
+				cmd_options, &opt_index);
+#else
+		opt = getopt_long_only(argc, argv, "pdks:",
+				cmd_options, &opt_index);
+#endif
+		switch (opt) {
+		case 's':
+			opts->raw_sig = true;
+			opts->raw_sig_name = optarg;
+			break;
+
+		case 'p':
+			opts->save_sig = true;
+			break;
+
+		case 'd':
+			opts->sign_only = true;
+			opts->save_sig = true;
+			break;
+
+#ifndef USE_PKCS7
+		case 'k':
+			opts->use_keyid = CMS_USE_KEYID;
+			break;
+#endif
+
+		case -1:
+			break;
+
+		default:
+			format();
+			break;
+		}
+	} while (opt != -1);
+}
+
 int main(int argc, char **argv)
 {
 	struct module_signature sig_info = { .id_type = PKEY_ID_PKCS7 };
 	char *hash_algo = NULL;
-	char *private_key_name = NULL, *raw_sig_name = NULL;
+	char *private_key_name = NULL;
 	char *x509_name, *module_name, *dest_name;
-	bool save_sig = false, replace_orig;
-	bool sign_only = false;
-	bool raw_sig = false;
 	unsigned char buf[4096];
 	unsigned long module_size, sig_size;
 	unsigned int use_signed_attrs;
@@ -229,13 +291,14 @@ int main(int argc, char **argv)
 	EVP_PKEY *private_key;
 #ifndef USE_PKCS7
 	CMS_ContentInfo *cms = NULL;
-	unsigned int use_keyid = 0;
 #else
 	PKCS7 *pkcs7 = NULL;
 #endif
 	X509 *x509;
 	BIO *bd, *bm;
-	int opt, n;
+	int n;
+	struct cmd_opts opts = {};
+
 	OpenSSL_add_all_algorithms();
 	ERR_load_crypto_strings();
 	ERR_clear_error();
@@ -247,23 +310,19 @@ int main(int argc, char **argv)
 #else
 	use_signed_attrs = PKCS7_NOATTR;
 #endif
+	parse_args(argc, argv, &opts);
+	argc -= optind;
+	argv += optind;
 
-	do {
-		opt = getopt(argc, argv, "sdpk");
-		switch (opt) {
-		case 's': raw_sig = true; break;
-		case 'p': save_sig = true; break;
-		case 'd': sign_only = true; save_sig = true; break;
+	const char *raw_sig_name = opts.raw_sig_name;
+	const bool save_sig = opts.save_sig;
+	const bool raw_sig = opts.raw_sig;
+	const bool sign_only = opts.sign_only;
+	bool replace_orig = opts.replace_orig;
 #ifndef USE_PKCS7
-		case 'k': use_keyid = CMS_USE_KEYID; break;
+	const unsigned int use_keyid = opts.use_keyid;
 #endif
-		case -1: break;
-		default: format();
-		}
-	} while (opt != -1);
 
-	argc -= optind;
-	argv += optind;
 	if (argc < 4 || argc > 5)
 		format();
 
-- 
2.41.0