umount-test-opts

 1#include <string.h>
 2
 3static int fsopt_matches(const char *opts_list, const char *opt, size_t optlen)
 4{
 5	int match = 1;
 6
 7	if (optlen >= 2 && opt[0] == 'n' && opt[1] == 'o') {
 8		match--;
 9		opt += 2; optlen -= 2;
10	}
11
12	if (optlen == 0)
13		return 0;
14	if (match && optlen > 1 && *opt == '+') {
15		opt++; optlen--;
16	}
17
18	while (1) {
19		if (strncmp(opts_list, opt, optlen) == 0) {
20			const char *after_opt = opts_list + optlen;
21			if (*after_opt == '\0' || *after_opt == ',')
22				return match;
23		}
24
25		opts_list = strchr(opts_list, ',');
26		if (!opts_list)
27			break;
28		opts_list++;
29	}
30
31	return !match;
32}
33
34int fsopts_matches(const char *opts_list, const char *reqopts_list)
35{
36	if (!reqopts_list)
37		return 1; /* no options requested, match anything */
38
39	while (1) {
40		size_t len;
41		const char *comma = strchr(reqopts_list, ',');
42		if (!comma)
43			len = strlen(reqopts_list);
44		else
45			len = comma - reqopts_list;
46
47		if (len && !fsopt_matches(opts_list, reqopts_list, len))
48			return 0;
49
50		if (!comma)
51			break;
52		reqopts_list = ++comma;
53	}
54
55	return 1;
56}