getsectsize.c revision a6ce1349539f866334ef3d5758bc2ee44a454acd 
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)
30#if !defined(BLKSSZGET)
31#define BLKSSZGET  _IO(0x12,104)/* get block device sector size */
32#endif
33#if !defined(BLKPBSZGET)
34#define BLKPBSZGET _IO(0x12,123)/* get block physical sector size */
35#endif
36#endif
37
38#include "ext2_fs.h"
39#include "ext2fs.h"
40
41/*
42 * Returns the logical sector size of a device
43 */
44errcode_t ext2fs_get_device_sectsize(const char *file, int *sectsize)
45{
46	int	fd;
47
48#ifdef HAVE_OPEN64
49	fd = open64(file, O_RDONLY);
50#else
51	fd = open(file, O_RDONLY);
52#endif
53	if (fd < 0)
54		return errno;
55
56#ifdef BLKSSZGET
57	if (ioctl(fd, BLKSSZGET, sectsize) >= 0) {
58		close(fd);
59		return 0;
60	}
61#endif
62	*sectsize = 0;
63	close(fd);
64	return 0;
65}
66
67/*
68 * Returns the physical sector size of a device
69 */
70errcode_t ext2fs_get_device_phys_sectsize(const char *file, int *sectsize)
71{
72	int	fd;
73
74#ifdef HAVE_OPEN64
75	fd = open64(file, O_RDONLY);
76#else
77	fd = open(file, O_RDONLY);
78#endif
79	if (fd < 0)
80		return errno;
81
82#ifdef BLKPBSZGET
83	if (ioctl(fd, BLKPBSZGET, sectsize) >= 0) {
84		close(fd);
85		return 0;
86	}
87#endif
88	*sectsize = 0;
89	close(fd);
90	return 0;
91}
92