Re: [Libguestfs] do_umount adjustment
Richard W.M. Jones wrote:
On Wed, Aug 12, 2009 at 10:14:51AM +0200, Jim Meyering wrote:
> Here's one final (I hope) question without a complete patch.
> Given that I already ensure that stubs.c invokes
> REQUIRE_ROOT_OR_RESOLVE_DEVICE just before calling do_umount,
> does this new version of do_umount look ok?
>
> /* Again, use the external /bin/umount program, so that /etc/mtab
> * is kept updated.
> */
> int
> do_umount (const char *pathordevice)
> {
> int r;
> char *err;
>
> char *buf = sysroot_path (pathordevice);
> if (buf == NULL) {
> reply_with_perror ("malloc");
> return -1;
> }
I think the problem here is you'll end up with a buf like
'/sysroot/dev/vda'.
In the original code:
if (strncmp (pathordevice, "/dev/", 5) == 0) {
buf = pathordevice;
IS_DEVICE (buf, -1);
} else {
buf = sysroot_path (pathordevice);
if (buf == NULL) {
reply_with_perror ("malloc");
return -1;
}
freeit = 1;
}
it avoids prefixing /dev paths.
No need for ugliness after all.
Here's a more faithful new version:
/* Again, use the external /bin/umount program, so that /etc/mtab
* is kept updated.
*/
int
do_umount (const char *pathordevice)
{
int r;
char *err;
char *buf = (strncmp (pathordevice, "/dev/", 5) == 0
? strdup (pathordevice)
: sysroot_path (pathordevice));
if (buf == NULL) {
reply_with_perror ("malloc");
return -1;
}
r = command (NULL, &err, "umount", buf, NULL);
free (buf);
if (r == -1) {
reply_with_error ("umount: %s: %s", pathordevice, err);
free (err);
return -1;
}
free (err);
/* update root_mounted? */
return 0;
}