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/* Demonstrate that setting disk->needs_clobber in ped_disk_duplicate
is necessary. With that, this test passes. Without it, the last
sectors of the disk are cleared, and this test fails. */
#include <config.h>
#include <parted/parted.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include "closeout.h"
#include "progname.h"
static void
seek_to_final_sector (int fd, PedSector ss)
{
/* Seek to EOF. */
off_t off = lseek (fd, 0, SEEK_END);
/* That had better succeed and determine that the size is > 2 sectors
and an exact multiple of ss. */
assert (2 * ss < off);
assert (off % ss == 0);
/* Back up one sector. */
off = lseek (fd, -ss, SEEK_CUR);
assert (0 < off);
}
static void
scribble_on_final_sector (char const *file_name, PedSector ss)
{
assert (0 < ss);
assert (ss % 512 == 0);
int fd = open (file_name, O_WRONLY);
assert (0 <= fd);
seek_to_final_sector (fd, ss);
/* Fill the final sector with ascii 'G's. */
char *buf = malloc (ss);
assert (buf);
memset (buf, 'G', ss);
assert (write (fd, buf, ss) == ss);
free (buf);
assert (close (fd) == 0);
}
int
main (int argc, char **argv)
{
atexit (close_stdout);
set_program_name (argv[0]);
if (argc != 1)
return EXIT_FAILURE;
char const *dev_name = "dev-file";
/* Create a file. */
int fd = open (dev_name, O_CREAT|O_TRUNC|O_WRONLY, 0644);
assert (0 <= fd);
off_t size = 8 * 1024 * 1024;
assert (ftruncate (fd, size) == 0);
assert (close (fd) == 0);
PedDevice *dev = ped_device_get (dev_name);
assert (dev);
PedDisk *disk = ped_disk_new_fresh (dev, ped_disk_type_get ("msdos"));
assert (disk);
assert (ped_disk_commit(disk));
PedSector ss = dev->sector_size;
scribble_on_final_sector (dev_name, ss);
/* Before the fix, this ped_disk_duplicate call would always set
copy->needs_clobber, thus causing the subsequent commit to
mistakenly clobber 9KiB at each end of the disk. */
PedDisk *copy = ped_disk_duplicate (disk);
assert (ped_disk_commit(copy));
ped_disk_destroy (copy);
ped_disk_destroy (disk);
ped_device_destroy (dev);
/* Read the final sector and ensure it's still all 'G's. */
fd = open (dev_name, O_RDONLY);
assert (0 <= fd);
seek_to_final_sector (fd, ss);
char *buf = malloc (ss);
assert (buf);
assert (read (fd, buf, ss) == ss);
unsigned int i;
for (i = 0; i < ss; i++)
assert (buf[i] == 'G');
free (buf);
return EXIT_SUCCESS;
}
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