util-linux/disk-utils/resizepart.c

119 lines
2.5 KiB
C

#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "c.h"
#include "nls.h"
#include "partx.h"
#include "sysfs.h"
#include "strutils.h"
#include "closestream.h"
static void __attribute__((__noreturn__)) usage(void)
{
FILE *out = stdout;
fputs(USAGE_HEADER, out);
fprintf(out, _(" %s <disk device> <partition number> <length>\n"),
program_invocation_short_name);
fputs(USAGE_SEPARATOR, out);
fputs(_("Tell the kernel about the new size of a partition.\n"), out);
fputs(USAGE_OPTIONS, out);
printf(USAGE_HELP_OPTIONS(16));
printf(USAGE_MAN_TAIL("resizepart(8)"));
exit(EXIT_SUCCESS);
}
static int get_partition_start(int fd, int partno, uint64_t *start)
{
struct stat st;
struct path_cxt *disk = NULL, *part = NULL;
dev_t devno = 0;
int rc = -1;
/*
* wholedisk
*/
if (fstat(fd, &st) || !S_ISBLK(st.st_mode))
goto done;
devno = st.st_rdev;
disk = ul_new_sysfs_path(devno, NULL, NULL);
if (!disk)
goto done;
/*
* partition
*/
devno = sysfs_blkdev_partno_to_devno(disk, partno);
if (!devno)
goto done;
part = ul_new_sysfs_path(devno, disk, NULL);
if (!part)
goto done;
if (ul_path_read_u64(part, start, "start"))
goto done;
rc = 0;
done:
ul_unref_path(part);
ul_unref_path(disk);
return rc;
}
int main(int argc, char **argv)
{
int c, fd, partno;
const char *wholedisk;
uint64_t start;
static const struct option longopts[] = {
{"help", no_argument, NULL, 'h'},
{"version", no_argument, NULL, 'V'},
{NULL, 0, NULL, '0'},
};
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
close_stdout_atexit();
while ((c = getopt_long(argc, argv, "Vh", longopts, NULL)) != -1)
switch (c) {
case 'V':
print_version(EXIT_SUCCESS);
case 'h':
usage();
default:
errtryhelp(EXIT_FAILURE);
}
if (argc != 4) {
warnx(_("not enough arguments"));
errtryhelp(EXIT_FAILURE);
}
wholedisk = argv[1];
partno = strtou32_or_err(argv[2], _("invalid partition number argument"));
if ((fd = open(wholedisk, O_RDONLY)) < 0)
err(EXIT_FAILURE, _("cannot open %s"), wholedisk);
if (get_partition_start(fd, partno, &start))
err(EXIT_FAILURE, _("%s: failed to get start of the partition number %s"),
wholedisk, argv[2]);
if (partx_resize_partition(fd, partno, start,
strtou64_or_err(argv[3], _("invalid length argument"))))
err(EXIT_FAILURE, _("failed to resize partition"));
if (close_fd(fd) != 0)
err(EXIT_FAILURE, _("write failed"));
return 0;
}