add support for non-option arguments extension to getopt

this is a GNU extension, activated by including '-' as the first
character of the options string, whereby non-option arguments are
processed as if they were arguments to an option character '\1' rather
than ending option processing.

src/misc/getopt.c

@@ -24,8 +24,20 @@ int getopt(int argc, char * const argv[], const char *optstring)
 		optind = 1;
 	}
 
-	if (optind >= argc || !argv[optind] || argv[optind][0] != '-' || !argv[optind][1])
+	if (optind >= argc || !argv[optind])
 		return -1;
+
+	if (argv[optind][0] != '-') {
+		if (optstring[0] == '-') {
+			optarg = argv[optind++];
+			return 1;
+		}
+		return -1;
+	}
+
+	if (!argv[optind][1])
+		return -1;
+
 	if (argv[optind][1] == '-' && !argv[optind][2])
 		return optind++, -1;
 
@@ -43,6 +55,9 @@ int getopt(int argc, char * const argv[], const char *optstring)
 		optpos = 0;
 	}
 
+	if (optstring[0] == '-')
+		optstring++;
+
 	for (i=0; (l = mbtowc(&d, optstring+i, MB_LEN_MAX)) && d!=c; i+=l>0?l:1);
 
 	if (d != c) {

src/misc/getopt_long.c

@@ -12,9 +12,10 @@ static int __getopt_long(int argc, char *const *argv, const char *optstring, con
 		__optpos = 0;
 		optind = 1;
 	}
-	if (optind >= argc || !argv[optind] || argv[optind][0] != '-') return -1;
-	if ((longonly && argv[optind][1]) ||
-		(argv[optind][1] == '-' && argv[optind][2]))
+	if (optind >= argc || !argv[optind]) return -1;
+	if (argv[optind][0] == '-' &&
+		((longonly && argv[optind][1]) ||
+		 (argv[optind][1] == '-' && argv[optind][2])))
 	{
 		int i;
 		for (i=0; longopts[i].name; i++) {