/*
* ext2fs_rename_replace_dotdot: Change the target of the `..' entry of
* the directory vp from fdvp to tdvp.
*/
static int
ext2fs_rename_replace_dotdot(struct vnode *vp,
struct vnode *fdvp, struct vnode *tdvp,
kauth_cred_t cred)
{
struct ext2fs_dirtemplate dirbuf;
int error;
/* XXX Does it make sense to do this before the sanity checks below? */
KASSERT(0 < VTOI(fdvp)->i_e2fs_nlink);
VTOI(fdvp)->i_e2fs_nlink--;
VTOI(fdvp)->i_flag |= IN_CHANGE;
error = ufs_bufio(UIO_READ, vp, &dirbuf, sizeof dirbuf, (off_t)0,
IO_NODELOCKED, cred, NULL, NULL);
if (error)
return error;
if (dirbuf.dotdot_namlen != 2 ||
dirbuf.dotdot_name[0] != '.' ||
dirbuf.dotdot_name[1] != '.') {
ufs_dirbad(VTOI(vp), (doff_t)12, "bad `..' entry");
return 0;
}
if (fs2h32(dirbuf.dotdot_ino) != VTOI(fdvp)->i_number) {
ufs_dirbad(VTOI(vp), (doff_t)12,
"`..' does not point at parent");
return 0;
}
dirbuf.dotdot_ino = h2fs32(VTOI(tdvp)->i_number);
/* XXX WTF? Why not check error? */
(void)ufs_bufio(UIO_WRITE, vp, &dirbuf, sizeof dirbuf, (off_t)0,
(IO_NODELOCKED | IO_SYNC), cred, NULL, NULL);
return 0;
}
/*
* Check if a directory is empty or not.
* Inode supplied must be locked.
*
* Using a struct dirtemplate here is not precisely
* what we want, but better than using a struct ext2fs_direct.
*
* NB: does not handle corrupted directories.
*/
int
ext2fs_dirempty(struct inode *ip, ino_t parentino, kauth_cred_t cred)
{
off_t off;
struct ext2fs_dirtemplate dbuf;
struct ext2fs_direct *dp = (struct ext2fs_direct *)&dbuf;
int error, namlen;
size_t count;
#define MINDIRSIZ (sizeof (struct ext2fs_dirtemplate) / 2)
for (off = 0; off < ext2fs_size(ip); off += fs2h16(dp->e2d_reclen)) {
error = ufs_bufio(UIO_READ, ITOV(ip), (void *)dp, MINDIRSIZ,
off, IO_NODELOCKED, cred, &count, NULL);
/*
* Since we read MINDIRSIZ, residual must
* be 0 unless we're at end of file.
*/
if (error || count != 0)
return (0);
/* avoid infinite loops */
if (dp->e2d_reclen == 0)
return (0);
/* skip empty entries */
if (dp->e2d_ino == 0)
continue;
/* accept only "." and ".." */
namlen = dp->e2d_namlen;
if (namlen > 2)
return (0);
if (dp->e2d_name[0] != '.')
return (0);
/*
* At this point namlen must be 1 or 2.
* 1 implies ".", 2 implies ".." if second
* char is also "."
*/
if (namlen == 1)
continue;
if (dp->e2d_name[1] == '.' && fs2h32(dp->e2d_ino) == parentino)
continue;
return (0);
}
return (1);
}
/*
* ext2fs_read_dotdot: Store in *ino_ret the inode number of the parent
* of the directory vp.
*/
static int
ext2fs_read_dotdot(struct vnode *vp, kauth_cred_t cred, ino_t *ino_ret)
{
struct ext2fs_dirtemplate dirbuf;
int error;
KASSERT(vp != NULL);
KASSERT(ino_ret != NULL);
KASSERT(vp->v_type == VDIR);
error = ufs_bufio(UIO_READ, vp, &dirbuf, sizeof dirbuf, (off_t)0,
IO_NODELOCKED, cred, NULL, NULL);
if (error)
return error;
if (dirbuf.dotdot_namlen != 2 ||
dirbuf.dotdot_name[0] != '.' ||
dirbuf.dotdot_name[1] != '.')
/* XXX Panic? Print warning? */
return ENOTDIR;
*ino_ret = fs2h32(dirbuf.dotdot_ino);
return 0;
}
