2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2003 Poul-Henning Kamp. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/eventhandler.h>
35 #include <sys/kernel.h>
38 #include <sys/vnode.h>
40 #include <fs/devfs/devfs.h>
41 #include <fs/devfs/devfs_int.h>
43 static d_open_t cttyopen;
45 static struct cdevsw ctty_cdevsw = {
46 .d_version = D_VERSION,
51 static struct cdev *ctty;
54 cttyopen(struct cdev *dev, int flag, int mode, struct thread *td)
61 ctty_clone(void *arg, struct ucred *cred, char *name, int namelen,
68 if (strcmp(name, "tty"))
71 sx_sunlock(&clone_drain_lock);
72 sx_slock(&proctree_lock);
73 sx_slock(&clone_drain_lock);
75 if (!(p->p_flag & P_CONTROLT))
77 else if (p->p_session->s_ttyvp == NULL)
79 else if (p->p_session->s_ttyvp->v_type == VBAD ||
80 p->p_session->s_ttyvp->v_rdev == NULL) {
81 /* e.g. s_ttyvp was revoked */
84 *dev = p->p_session->s_ttyvp->v_rdev;
87 sx_sunlock(&proctree_lock);
91 ctty_drvinit(void *unused)
94 EVENTHANDLER_REGISTER(dev_clone, ctty_clone, 0, 1000);
95 ctty = make_dev_credf(MAKEDEV_ETERNAL, &ctty_cdevsw, 0, NULL, UID_ROOT,
96 GID_WHEEL, 0666, "ctty");
99 SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,ctty_drvinit,NULL);