1/* See LICENSE file for copyright and license details. */
 2
 3
 4#include <sys/ioctl.h>
 5#include <sys/stat.h>
 6#include <sys/types.h>
 7
 8#include <fcntl.h>
 9#include <stdio.h>
10#include <stdlib.h>
11#include <unistd.h>
12
13#include "util.h"
14
15#define FIFREEZE	_IOWR('X', 119, int)	/* Freeze */
16#define FITHAW		_IOWR('X', 120, int)	/* Thaw */
17
18static void
19usage(void)
20{
21	eprintf("usage: %s (-f | -u) mountpoint\n", argv0);
22}
23
24// ?man fsfreeze: suspend access to a filesystem
25// ?man arguments: (-f | -u) mountpoint
26// ?man freeze or unfreeze a filesystem to allow safe backups
27int
28main(int argc, char *argv[])
29{
30	int fflag = 0;
31	int uflag = 0;
32	long p = 1;
33	int fd;
34
35	ARGBEGIN {
36	// ?man -f: force the operation
37	case 'f':
38		fflag = 1;
39		break;
40	// ?man -u: unbuffered output
41	case 'u':
42		uflag = 1;
43		break;
44	default:
45		usage();
46	} ARGEND;
47
48	if (argc != 1)
49		usage();
50
51	if ((fflag ^ uflag) == 0)
52		usage();
53
54	fd = open(argv[0], O_RDONLY);
55	if (fd < 0)
56		eprintf("open: %s:", argv[0]);
57	if (ioctl(fd, fflag == 1 ? FIFREEZE : FITHAW, &p) < 0)
58		eprintf("%s %s:", fflag == 1 ? "FIFREEZE" : "FITHAW", argv[0]);
59	close(fd);
60	return 0;
61}