+ /*
+ * 2) If target doesn't exist, link the target
+ * to the source and unlink the source.
+ * Otherwise, rewrite the target directory
+ * entry to reference the source inode and
+ * expunge the original entry's existence.
+ */
+ if (xp == NULL) {
+ if (dp->i_dev != ip->i_dev)
+ panic("rename: EXDEV");
+ /*
+ * Account for ".." in new directory.
+ * When source and destination have the same
+ * parent we don't fool with the link count.
+ */
+ if (doingdirectory && newparent) {
+ if ((nlink_t)dp->i_nlink >= LINK_MAX) {
+ error = EMLINK;
+ goto bad;
+ }
+ dp->i_nlink++;
+ dp->i_flag |= ICHG;
+ if (error = VOP_UPDATE(tdvp, &tv, &tv, 1))
+ goto bad;
+ }
+ if (error = ufs_direnter(ip, tdvp, tcnp)) {
+ if (doingdirectory && newparent) {
+ dp->i_nlink--;
+ dp->i_flag |= ICHG;
+ (void)VOP_UPDATE(tdvp, &tv, &tv, 1);
+ }
+ goto bad;
+ }
+ vput(tdvp);
+ } else {
+ if (xp->i_dev != dp->i_dev || xp->i_dev != ip->i_dev)
+ panic("rename: EXDEV");
+ /*
+ * Short circuit rename(foo, foo).
+ */
+ if (xp->i_number == ip->i_number)
+ panic("rename: same file");
+ /*
+ * If the parent directory is "sticky", then the user must
+ * own the parent directory, or the destination of the rename,
+ * otherwise the destination may not be changed (except by
+ * root). This implements append-only directories.
+ */
+ if ((dp->i_mode & ISVTX) && tcnp->cn_cred->cr_uid != 0 &&
+ tcnp->cn_cred->cr_uid != dp->i_uid &&
+ xp->i_uid != tcnp->cn_cred->cr_uid) {
+ error = EPERM;
+ goto bad;
+ }
+ /*
+ * Target must be empty if a directory and have no links
+ * to it. Also, ensure source and target are compatible
+ * (both directories, or both not directories).
+ */
+ if ((xp->i_mode&IFMT) == IFDIR) {
+ if (!ufs_dirempty(xp, dp->i_number, tcnp->cn_cred) ||
+ xp->i_nlink > 2) {
+ error = ENOTEMPTY;
+ goto bad;
+ }
+ if (!doingdirectory) {
+ error = ENOTDIR;
+ goto bad;
+ }
+ cache_purge(tdvp);
+ } else if (doingdirectory) {
+ error = EISDIR;
+ goto bad;
+ }
+ if (error = ufs_dirrewrite(dp, ip, tcnp))
+ goto bad;
+ /*
+ * If the target directory is in the same
+ * directory as the source directory,
+ * decrement the link count on the parent
+ * of the target directory.
+ */
+ if (doingdirectory && !newparent) {
+ dp->i_nlink--;
+ dp->i_flag |= ICHG;
+ }
+ vput(tdvp);
+ /*
+ * Adjust the link count of the target to
+ * reflect the dirrewrite above. If this is
+ * a directory it is empty and there are
+ * no links to it, so we can squash the inode and
+ * any space associated with it. We disallowed
+ * renaming over top of a directory with links to
+ * it above, as the remaining link would point to
+ * a directory without "." or ".." entries.
+ */
+ xp->i_nlink--;
+ if (doingdirectory) {
+ if (--xp->i_nlink != 0)
+ panic("rename: linked directory");
+ error = VOP_TRUNCATE(tvp, (off_t)0, IO_SYNC,
+ tcnp->cn_cred, tcnp->cn_proc);
+ }
+ xp->i_flag |= ICHG;
+ vput(tvp);
+ xp = NULL;
+ }
+
+ /*
+ * 3) Unlink the source.
+ */
+ fcnp->cn_flags &= ~MODMASK;
+ fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
+ if ((fcnp->cn_flags & SAVESTART) == 0)
+ panic("ufs_rename: lost from startdir");
+ (void) relookup(fdvp, &fvp, fcnp);
+ if (fvp != NULL) {
+ xp = VTOI(fvp);
+ dp = VTOI(fdvp);
+ } else {
+ /*
+ * From name has disappeared.
+ */
+ if (doingdirectory)
+ panic("rename: lost dir entry");
+ vrele(ap->a_fvp);
+ return (0);
+ }
+ /*
+ * Ensure that the directory entry still exists and has not
+ * changed while the new name has been entered. If the source is
+ * a file then the entry may have been unlinked or renamed. In
+ * either case there is no further work to be done. If the source
+ * is a directory then it cannot have been rmdir'ed; its link
+ * count of three would cause a rmdir to fail with ENOTEMPTY.
+ * The IRENAME flag ensures that it cannot be moved by another
+ * rename.
+ */
+ if (xp != ip) {
+ if (doingdirectory)
+ panic("rename: lost dir entry");
+ } else {
+ /*
+ * If the source is a directory with a
+ * new parent, the link count of the old
+ * parent directory must be decremented
+ * and ".." set to point to the new parent.
+ */
+ if (doingdirectory && newparent) {
+ dp->i_nlink--;
+ dp->i_flag |= ICHG;
+ error = vn_rdwr(UIO_READ, fvp, (caddr_t)&dirbuf,
+ sizeof (struct dirtemplate), (off_t)0,
+ UIO_SYSSPACE, IO_NODELOCKED,
+ tcnp->cn_cred, (int *)0, (struct proc *)0);
+ if (error == 0) {
+# if (BYTE_ORDER == LITTLE_ENDIAN)
+ if (fvp->v_mount->mnt_maxsymlinklen <= 0)
+ namlen = dirbuf.dotdot_type;
+ else
+ namlen = dirbuf.dotdot_namlen;
+# else
+ namlen = dirbuf.dotdot_namlen;
+# endif
+ if (namlen != 2 ||
+ dirbuf.dotdot_name[0] != '.' ||
+ dirbuf.dotdot_name[1] != '.') {
+ ufs_dirbad(xp, (doff_t)12,
+ "rename: mangled dir");
+ } else {
+ dirbuf.dotdot_ino = newparent;
+ (void) vn_rdwr(UIO_WRITE, fvp,
+ (caddr_t)&dirbuf,
+ sizeof (struct dirtemplate),
+ (off_t)0, UIO_SYSSPACE,
+ IO_NODELOCKED|IO_SYNC,
+ tcnp->cn_cred, (int *)0,
+ (struct proc *)0);
+ cache_purge(fdvp);
+ }
+ }
+ }
+ error = ufs_dirremove(fdvp, fcnp);
+ if (!error) {
+ xp->i_nlink--;
+ xp->i_flag |= ICHG;
+ }
+ xp->i_flag &= ~IRENAME;
+ }
+ if (dp)
+ vput(fdvp);
+ if (xp)
+ vput(fvp);
+ vrele(ap->a_fvp);
+ return (error);
+
+bad:
+ if (xp)
+ vput(ITOV(xp));
+ vput(ITOV(dp));
projects / unix-history / blobdiff