bsd/kern/tty_tty.c

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License.  The rights granted to you under the
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /* Copyright (c) 1997 Apple Computer, Inc. All Rights Reserved */
  31 /*-
  32  * Copyright (c) 1982, 1986, 1991, 1993
  33  *      The Regents of the University of California.  All rights reserved.
  34  *
  35  * Redistribution and use in source and binary forms, with or without
  36  * modification, are permitted provided that the following conditions
  37  * are met:
  38  * 1. Redistributions of source code must retain the above copyright
  39  *    notice, this list of conditions and the following disclaimer.
  40  * 2. Redistributions in binary form must reproduce the above copyright
  41  *    notice, this list of conditions and the following disclaimer in the
  42  *    documentation and/or other materials provided with the distribution.
  43  * 3. All advertising materials mentioning features or use of this software
  44  *    must display the following acknowledgement:
  45  *      This product includes software developed by the University of
  46  *      California, Berkeley and its contributors.
  47  * 4. Neither the name of the University nor the names of its contributors
  48  *    may be used to endorse or promote products derived from this software
  49  *    without specific prior written permission.
  50  *
  51  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  53  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  54  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  55  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  56  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  57  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  58  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  59  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  60  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  61  * SUCH DAMAGE.
  62  *
  63  *      @(#)tty_tty.c   8.2 (Berkeley) 9/23/93
  64  */
  65
  66 /*
  67  * Indirect driver for controlling tty.
  68  */
  69 #include <sys/param.h>
  70 #include <sys/systm.h>
  71 #include <sys/conf.h>
  72 #include <sys/ioctl.h>
  73 #include <sys/proc_internal.h>
  74 #include <sys/tty.h>
  75 #include <sys/vnode_internal.h>
  76 #include <sys/file_internal.h>
  77 #ifndef NeXT
  78 #include <sys/kernel.h>
  79 #ifdef DEVFS
  80 #include <sys/devfsext.h>
  81 #endif /*DEVFS*/
  82
  83 static  d_open_t        cttyopen;
  84 static  d_read_t        cttyread;
  85 static  d_write_t       cttywrite;
  86 static  d_ioctl_t       cttyioctl;
  87 static  d_select_t      cttyselect;
  88
  89 #endif /* !NeXT */
  90
  91 /* Forward declarations for cdevsw[] entry */
  92 /* XXX we should consider making these static */
  93 int cttyopen(dev_t dev, int flag, int mode, struct proc *p);
  94 int cttyread(dev_t dev, struct uio *uio, int flag);
  95 int cttywrite(dev_t dev, struct uio *uio, int flag);
  96 int cttyioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p);
  97 int cttyselect(dev_t dev, int flag, void* wql, struct proc *p);
  98
  99 #ifndef NeXT
 100
 101 #define CDEV_MAJOR 1
 102 /* Don't make static, fdesc_vnops uses this. */
 103 struct cdevsw ctty_cdevsw =
 104         { cttyopen,     nullclose,      cttyread,       cttywrite,      /*1*/
 105           cttyioctl,    nullstop,       nullreset,      nodevtotty,/* tty */
 106           cttyselect,   nommap,         NULL,   "ctty", NULL,   -1 };
 107
 108 #endif /* !NeXT */
 109
 110 #define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
 111
 112 /*ARGSUSED*/
 113 int
 114 cttyopen(__unused dev_t dev, int flag, __unused int mode, struct proc *p)
 115 {
 116         struct vnode *ttyvp = cttyvp(p);
 117         struct vfs_context context;
 118         int error;
 119
 120         if (ttyvp == NULL)
 121                 return (ENXIO);
 122
 123         context.vc_proc = p;
 124         context.vc_ucred = p->p_ucred;
 125         error = VNOP_OPEN(ttyvp, flag, &context);
 126
 127         return (error);
 128 }
 129
 130 /*ARGSUSED*/
 131 int
 132 cttyread(__unused dev_t dev, struct uio *uio, int flag)
 133 {
 134         struct proc *p = current_proc();
 135         register struct vnode *ttyvp = cttyvp(p);
 136         struct vfs_context context;
 137         int error;
 138
 139         if (ttyvp == NULL)
 140                 return (EIO);
 141
 142         context.vc_proc = p;
 143         context.vc_ucred = NOCRED;
 144
 145         error = VNOP_READ(ttyvp, uio, flag, &context);
 146
 147         return (error);
 148 }
 149
 150 /*ARGSUSED*/
 151 int
 152 cttywrite(__unused dev_t dev, struct uio *uio, int flag)
 153 {
 154         struct proc *p = current_proc();
 155         register struct vnode *ttyvp = cttyvp(p);
 156         struct vfs_context context;
 157         int error;
 158
 159         if (ttyvp == NULL)
 160                 return (EIO);
 161
 162         context.vc_proc = p;
 163         context.vc_ucred = NOCRED;
 164
 165         error = VNOP_WRITE(ttyvp, uio, flag, &context);
 166
 167         return (error);
 168 }
 169
 170 /*ARGSUSED*/
 171 #ifndef NeXT
 172 static  int
 173 cttyioctl(dev, cmd, addr, flag, p)
 174         dev_t dev;
 175         int cmd;
 176         caddr_t addr;
 177         int flag;
 178         struct proc *p;
 179 #else
 180 int
 181 cttyioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flag,
 182         struct proc *p)
 183 #endif /* !NeXT */
 184 {
 185         struct vnode *ttyvp = cttyvp(p);
 186         struct vfs_context context;
 187
 188         if (ttyvp == NULL)
 189                 return (EIO);
 190         if (cmd == TIOCSCTTY)  /* don't allow controlling tty to be set    */
 191                 return EINVAL; /* to controlling tty -- infinite recursion */
 192         if (cmd == TIOCNOTTY) {
 193                 if (!SESS_LEADER(p)) {
 194                         p->p_flag &= ~P_CONTROLT;
 195                         return (0);
 196                 } else
 197                         return (EINVAL);
 198         }
 199         context.vc_proc = p;
 200         context.vc_ucred = NOCRED;
 201
 202         return (VNOP_IOCTL(ttyvp, cmd, addr, flag, &context));
 203 }
 204
 205 /*ARGSUSED*/
 206 int
 207 cttyselect(__unused dev_t dev, int flag, void* wql, struct proc *p)
 208 {
 209         struct vnode *ttyvp = cttyvp(p);
 210         struct vfs_context context;
 211
 212         context.vc_proc = p;
 213         context.vc_ucred = NOCRED;
 214
 215         if (ttyvp == NULL)
 216                 return (1);     /* try operation to get EOF/failure */
 217         return (VNOP_SELECT(ttyvp, flag, FREAD|FWRITE, wql, &context));
 218 }
 219
 220 #ifndef NeXT
 221 static ctty_devsw_installed = 0;
 222 #ifdef DEVFS
 223 static  void    *ctty_devfs_token;
 224 #endif
 225
 226 static void
 227 ctty_drvinit(void *unused)
 228 {
 229         dev_t dev;
 230
 231         if( ! ctty_devsw_installed ) {
 232                 dev = makedev(CDEV_MAJOR,0);
 233                 cdevsw_add(&dev,&ctty_cdevsw,NULL);
 234                 ctty_devsw_installed = 1;
 235 #ifdef DEVFS
 236                 ctty_devfs_token =
 237                         devfs_add_devswf(&ctty_cdevsw, 0, DV_CHR, 0, 0,
 238                                         0666, "tty");
 239 #endif
 240         }
 241 }
 242
 243 SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,ctty_drvinit,NULL)
 244
 245
 246 #endif /* !NeXT */