1 /* $OpenBSD: tty_tty.c,v 1.18 2016/03/19 12:04:15 natano Exp $ */ 2 /* $NetBSD: tty_tty.c,v 1.13 1996/03/30 22:24:46 christos Exp $ */ 3 4 /*- 5 * Copyright (c) 1982, 1986, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)tty_tty.c 8.2 (Berkeley) 9/23/93 33 */ 34 35 /* 36 * Indirect driver for controlling tty. 37 */ 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/ioctl.h> 41 #include <sys/proc.h> 42 #include <sys/tty.h> 43 #include <sys/vnode.h> 44 #include <sys/lock.h> 45 #include <sys/file.h> 46 47 48 #define cttyvp(p) \ 49 ((p)->p_p->ps_flags & PS_CONTROLT ? \ 50 (p)->p_p->ps_session->s_ttyvp : NULL) 51 52 int 53 cttyopen(dev_t dev, int flag, int mode, struct proc *p) 54 { 55 struct vnode *ttyvp = cttyvp(p); 56 int error; 57 58 if (ttyvp == NULL) 59 return (ENXIO); 60 vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, p); 61 error = VOP_OPEN(ttyvp, flag, NOCRED, p); 62 VOP_UNLOCK(ttyvp, p); 63 return (error); 64 } 65 66 int 67 cttyread(dev_t dev, struct uio *uio, int flag) 68 { 69 struct proc *p = uio->uio_procp; 70 struct vnode *ttyvp = cttyvp(uio->uio_procp); 71 int error; 72 73 if (ttyvp == NULL) 74 return (EIO); 75 vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, p); 76 error = VOP_READ(ttyvp, uio, flag, NOCRED); 77 VOP_UNLOCK(ttyvp, p); 78 return (error); 79 } 80 81 int 82 cttywrite(dev_t dev, struct uio *uio, int flag) 83 { 84 struct proc *p = uio->uio_procp; 85 struct vnode *ttyvp = cttyvp(uio->uio_procp); 86 int error; 87 88 if (ttyvp == NULL) 89 return (EIO); 90 vn_lock(ttyvp, LK_EXCLUSIVE | LK_RETRY, p); 91 error = VOP_WRITE(ttyvp, uio, flag, NOCRED); 92 VOP_UNLOCK(ttyvp, p); 93 return (error); 94 } 95 96 int 97 cttyioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p) 98 { 99 struct vnode *ttyvp = cttyvp(p); 100 101 if (ttyvp == NULL) 102 return (EIO); 103 if (cmd == TIOCSCTTY) /* XXX */ 104 return (EINVAL); 105 if (cmd == TIOCNOTTY) { 106 if (!SESS_LEADER(p->p_p)) { 107 atomic_clearbits_int(&p->p_p->ps_flags, PS_CONTROLT); 108 return (0); 109 } else 110 return (EINVAL); 111 } 112 return (VOP_IOCTL(ttyvp, cmd, addr, flag, NOCRED, p)); 113 } 114 115 int 116 cttypoll(dev_t dev, int events, struct proc *p) 117 { 118 struct vnode *ttyvp = cttyvp(p); 119 120 if (ttyvp == NULL) /* try operation to get EOF/failure */ 121 return (seltrue(dev, events, p)); 122 return (VOP_POLL(ttyvp, FREAD|FWRITE, events, p)); 123 } 124 125 int 126 cttykqfilter(dev_t dev, struct knote *kn) 127 { 128 struct vnode *ttyvp = cttyvp(curproc); 129 130 if (ttyvp == NULL) 131 return (ENXIO); 132 return (VOP_KQFILTER(ttyvp, kn)); 133 } 134