getsectsize.c revision 543547a52a20cb7e69d74921b2f691078fd55d83 
1/*
2 * getsectsize.c --- get the sector size of a device.
3 *
4 * Copyright (C) 1995, 1995 Theodore Ts'o.
5 * Copyright (C) 2003 VMware, Inc.
6 *
7 * %Begin-Header%
8 * This file may be redistributed under the terms of the GNU Library
9 * General Public License, version 2.
10 * %End-Header%
11 */
12
13#define _LARGEFILE_SOURCE
14#define _LARGEFILE64_SOURCE
15
16#include <stdio.h>
17#if HAVE_UNISTD_H
18#include <unistd.h>
19#endif
20#if HAVE_ERRNO_H
21#include <errno.h>
22#endif
23#include <fcntl.h>
24#ifdef HAVE_LINUX_FD_H
25#include <sys/ioctl.h>
26#include <linux/fd.h>
27#endif
28
29#if defined(__linux__) && defined(_IO) && !defined(BLKSSZGET)
30#define BLKSSZGET  _IO(0x12,104)/* get block device sector size */
31#endif
32
33#include "ext2_fs.h"
34#include "ext2fs.h"
35
36/*
37 * Returns the number of blocks in a partition
38 */
39errcode_t ext2fs_get_device_sectsize(const char *file, int *sectsize)
40{
41	int	fd;
42
43#ifdef HAVE_OPEN64
44	fd = open64(file, O_RDONLY);
45#else
46	fd = open(file, O_RDONLY);
47#endif
48	if (fd < 0)
49		return errno;
50
51#ifdef BLKSSZGET
52	if (ioctl(fd, BLKSSZGET, sectsize) >= 0) {
53		close(fd);
54		return 0;
55	}
56#endif
57	*sectsize = 0;
58	close(fd);
59	return 0;
60}
61