static inline int opt_len(const char *s)
{
	bool open_quote = false;
	int len;
	char c;

	for (len = 0; (c = s[len]) != '\0'; len++) {
		if (c == '"')
			open_quote = !open_quote;
		if (c == ',' && !open_quote)
			break;
	}
	return len;
}