micro-utils/include/libmu/parse_mount.h

#ifndef _PARSE_MOUNT_H
#define _PARSE_MOUNT_H
#include <string.h>

typedef struct {
	char *opt;
	char *notopt;
	char *desc;
	unsigned int val;
} MU_MOUNT_OPTS;

MU_MOUNT_OPTS mu_options[] = {
	{"defaults", NULL,     NULL, 0},
	{"ro",       "rw",     "Read only / Read and write", MS_RDONLY},
	{"remount",  NULL,     "Remount a mounted filesystem", MS_REMOUNT},
	{"sync",     "async",  "Writes are [a]synchronous", MS_SYNCHRONOUS},
	{"nodev",    "dev",    "(Dis)allow use of special device files", MS_NODEV},
	{"bind",     "rbind",  "Bind a file or directory", MS_BIND},
	{"noexec",   "exec",   "(Dis)allow use of executable files", MS_NOEXEC},
	{"noatime",  "atime",  "Disable/enable updates to inode access times", MS_NOATIME}
};

unsigned long mu_parse_opts(char *str, char *data, const size_t data_size) {
	memset(data, '\0', data_size);
	unsigned long opt = 0;
	size_t data_len = 0;

	char *token = strtok(str, ",");
	while (token != NULL) {
		int invalidopt = 1;
		for (size_t i = 0; i < sizeof(mu_options) / sizeof(mu_options[0]); i++) {
			if (mu_options[i].opt && !strcmp(token, mu_options[i].opt)) {
				opt |= mu_options[i].val;
				invalidopt = 0;
				break;
			}

			if (mu_options[i].notopt && !strcmp(token, mu_options[i].notopt)) {
				opt &= ~mu_options[i].val;
				invalidopt = 0;
				break;
			}
		}

		/* Unknow opt, pass in mount() */
		size_t len = strlen(token);
		if (invalidopt && len > 0) {
			/* Copy token string */
			for (size_t i = 0; i < len; i++) {
				if (data_len + 1 >= data_size)
					break;

				else {
					data[data_len] = token[i];
					data_len++;
				}
			}

			if (data_len && data_len + 1 < data_size)
				data[data_len++] = ',';
		}

		token = strtok(NULL, ",");
	}

	if (data_len > 0)
		data[data_len - 1] = '\0';

	return opt;
}

#endif