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/*
* getsize.c --- get the size of a partition.
*
* Copyright (C) 1995, 1995 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
* %End-Header%
*/
#ifndef _LARGEFILE_SOURCE
#define _LARGEFILE_SOURCE
#endif
#ifndef _LARGEFILE64_SOURCE
#define _LARGEFILE64_SOURCE
#endif
#include "config.h"
#include "blkidP.h"
#include <stdio.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_ERRNO_H
#include <errno.h>
#endif
#include <fcntl.h>
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#ifdef HAVE_LINUX_FD_H
#include <linux/fd.h>
#endif
#ifdef HAVE_SYS_DISKLABEL_H
#include <sys/disklabel.h>
#endif
#ifdef HAVE_SYS_DISK_H
#include <sys/disk.h>
#endif
#ifdef __linux__
#include <sys/utsname.h>
#endif
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if defined(__linux__) && defined(_IO) && !defined(BLKGETSIZE)
#define BLKGETSIZE _IO(0x12,96) /* return device size */
#endif
#if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64)
#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
#endif
#ifdef APPLE_DARWIN
#define BLKGETSIZE DKIOCGETBLOCKCOUNT32
#endif /* APPLE_DARWIN */
static int valid_offset(int fd, blkid_loff_t offset)
{
char ch;
if (blkid_llseek(fd, offset, 0) < 0)
return 0;
if (read(fd, &ch, 1) < 1)
return 0;
return 1;
}
/*
* Returns the number of bytes in a partition
*/
blkid_loff_t blkid_get_dev_size(int fd)
{
unsigned long long size64 __BLKID_ATTR((unused));
blkid_loff_t high, low;
#if defined DKIOCGETBLOCKCOUNT && defined DKIOCGETBLOCKSIZE /* For Apple Darwin */
unsigned int size;
if (ioctl(fd, DKIOCGETBLOCKCOUNT, &size64) >= 0 &&
ioctl(fd, DKIOCGETBLOCKSIZE, &size) >= 0) {
if (sizeof(blkid_loff_t) < sizeof(unsigned long long) &&
(size64 * size) > 0xFFFFFFFF)
return 0; /* EFBIG */
return (blkid_loff_t)size64 * size;
}
#endif
#ifdef BLKGETSIZE64
{
int valid_blkgetsize64 = 1;
#ifdef __linux__
struct utsname ut;
if ((uname(&ut) == 0) &&
((ut.release[0] == '2') && (ut.release[1] == '.') &&
(ut.release[2] < '6') && (ut.release[3] == '.')))
valid_blkgetsize64 = 0;
#endif
if (valid_blkgetsize64 &&
ioctl(fd, BLKGETSIZE64, &size64) >= 0) {
if (sizeof(blkid_loff_t) < sizeof(unsigned long long) &&
(size64 > 0xFFFFFFFF))
return 0; /* EFBIG */
return size64;
}
}
#endif /* BLKGETSIZE64 */
#ifdef BLKGETSIZE
{
unsigned long size;
if (ioctl(fd, BLKGETSIZE, &size) >= 0)
return (blkid_loff_t)size << 9;
}
#endif
/* tested on FreeBSD 6.1-RELEASE i386 */
#ifdef DIOCGMEDIASIZE
if (ioctl(fd, DIOCGMEDIASIZE, &size64) >= 0)
return (off_t)size64;
#endif /* DIOCGMEDIASIZE */
#ifdef FDGETPRM
{
struct floppy_struct this_floppy;
if (ioctl(fd, FDGETPRM, &this_floppy) >= 0)
return (blkid_loff_t)this_floppy.size << 9;
}
#endif
#if defined(HAVE_SYS_DISKLABEL_H) && defined(DIOCGDINFO)
{
int part = -1;
struct disklabel lab;
struct partition *pp;
char ch;
struct stat st;
/*
* This code works for FreeBSD 4.11 i386, except for the full
* device (such as /dev/ad0). It doesn't work properly for
* newer FreeBSD though. FreeBSD >= 5.0 should be covered by
* the DIOCGMEDIASIZE above however.
*
* Note that FreeBSD >= 4.0 has disk devices as unbuffered (raw,
* character) devices, so we need to check for S_ISCHR, too.
*/
if (fstat(fd, &st) >= 0 &&
blkidP_is_disk_device(st.st_mode))
part = st.st_rdev & 7;
if (part >= 0 && (ioctl(fd, DIOCGDINFO, (char *)&lab) >= 0)) {
pp = &lab.d_partitions[part];
if (pp->p_size)
return pp->p_size << 9;
}
}
#endif /* defined(HAVE_SYS_DISKLABEL_H) && defined(DIOCGDINFO) */
{
#if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
struct stat64 st;
if (fstat64(fd, &st) == 0)
#else
struct stat st;
if (fstat(fd, &st) == 0)
#endif
if (S_ISREG(st.st_mode))
return st.st_size;
}
/*
* OK, we couldn't figure it out by using a specialized ioctl,
* which is generally the best way. So do binary search to
* find the size of the partition.
*/
low = 0;
for (high = 1024; valid_offset(fd, high); high *= 2)
low = high;
while (low < high - 1) {
const blkid_loff_t mid = (low + high) / 2;
if (valid_offset(fd, mid))
low = mid;
else
high = mid;
}
return low + 1;
}
#ifdef TEST_PROGRAM
int main(int argc, char **argv)
{
long long bytes;
int fd;
if (argc < 2) {
fprintf(stderr, "Usage: %s device\n"
"Determine the size of a device\n", argv[0]);
return 1;
}
if ((fd = open(argv[1], O_RDONLY)) < 0)
perror(argv[0]);
bytes = blkid_get_dev_size(fd);
printf("Device %s has %lld 1k blocks.\n", argv[1],
(unsigned long long)bytes >> 10);
return 0;
}
#endif
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