lib/cmdline: don't crash if value for a parameter is missing

Signed-off-by: Adam Wujek <dev_public@wujek.eu>

lib/cmdline.c

@@ -72,22 +72,36 @@ int pp_parse_cmdline(struct pp_globals *ppg, int argc, char **argv)
 		switch (a[1]) {
 		case 'd':
 			/* Use the general flags, per-instance TBD */
-			a = argv[++i];
+			if (!(a = argv[++i])) {
+				err = 1;
+				break;
+			}
 			pp_global_d_flags = pp_diag_parse(a);
 			break;
 		case 'C':
-			if (pp_config_string(ppg, argv[++i]) != 0)
+			if (!(a = argv[++i])) {
+				err = 1;
+				break;
+			}
+			if (pp_config_string(ppg, a) != 0)
 				return -1;
 			break;
 		case 'f':
-			if (pp_config_file(ppg, 1, argv[++i]) != 0)
+			if (!(a = argv[++i])) {
+				err = 1;
+				break;
+			}
+			if (pp_config_file(ppg, 1, a) != 0)
 				return -1;
 			break;
 		case 't':
 			GOPTS(ppg)->flags |= PP_FLAG_NO_ADJUST;
 			break;
 		case 'w':
-			a = argv[++i];
+			if (!(a = argv[++i])) {
+				err = 1;
+				break;
+			}
 			GOPTS(ppg)->s = atoi(a);
 			break;
 		case 'h':
@@ -96,6 +110,11 @@ int pp_parse_cmdline(struct pp_globals *ppg, int argc, char **argv)
 		case 'G':
 			/* gptp_mode not supported: fall through */
 		default:
+			err = 1;
+			break;
+		}
+		if (err) {
+			pp_printf("Wrong parameter!\n\n");
 			cmd_line_print_help();
 			return -1;
 		}