bsd/kern/tty_tty.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 /* Copyright (c) 1997 Apple Computer, Inc. All Rights Reserved */
  24 /*-
  25  * Copyright (c) 1982, 1986, 1991, 1993
  26  *      The Regents of the University of California.  All rights reserved.
  27  *
  28  * Redistribution and use in source and binary forms, with or without
  29  * modification, are permitted provided that the following conditions
  30  * are met:
  31  * 1. Redistributions of source code must retain the above copyright
  32  *    notice, this list of conditions and the following disclaimer.
  33  * 2. Redistributions in binary form must reproduce the above copyright
  34  *    notice, this list of conditions and the following disclaimer in the
  35  *    documentation and/or other materials provided with the distribution.
  36  * 3. All advertising materials mentioning features or use of this software
  37  *    must display the following acknowledgement:
  38  *      This product includes software developed by the University of
  39  *      California, Berkeley and its contributors.
  40  * 4. Neither the name of the University nor the names of its contributors
  41  *    may be used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  54  * SUCH DAMAGE.
  55  *
  56  *      @(#)tty_tty.c   8.2 (Berkeley) 9/23/93
  57  */
  58
  59 /*
  60  * Indirect driver for controlling tty.
  61  */
  62 #include <sys/param.h>
  63 #include <sys/systm.h>
  64 #include <sys/conf.h>
  65 #include <sys/ioctl.h>
  66 #include <sys/proc_internal.h>
  67 #include <sys/tty.h>
  68 #include <sys/vnode_internal.h>
  69 #include <sys/file_internal.h>
  70 #ifndef NeXT
  71 #include <sys/kernel.h>
  72 #ifdef DEVFS
  73 #include <sys/devfsext.h>
  74 #endif /*DEVFS*/
  75
  76 static  d_open_t        cttyopen;
  77 static  d_read_t        cttyread;
  78 static  d_write_t       cttywrite;
  79 static  d_ioctl_t       cttyioctl;
  80 static  d_select_t      cttyselect;
  81
  82 #endif /* !NeXT */
  83
  84 /* Forward declarations for cdevsw[] entry */
  85 /* XXX we should consider making these static */
  86 int cttyopen(dev_t dev, int flag, int mode, struct proc *p);
  87 int cttyread(dev_t dev, struct uio *uio, int flag);
  88 int cttywrite(dev_t dev, struct uio *uio, int flag);
  89 int cttyioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p);
  90 int cttyselect(dev_t dev, int flag, void* wql, struct proc *p);
  91
  92 #ifndef NeXT
  93
  94 #define CDEV_MAJOR 1
  95 /* Don't make static, fdesc_vnops uses this. */
  96 struct cdevsw ctty_cdevsw =
  97         { cttyopen,     nullclose,      cttyread,       cttywrite,      /*1*/
  98           cttyioctl,    nullstop,       nullreset,      nodevtotty,/* tty */
  99           cttyselect,   nommap,         NULL,   "ctty", NULL,   -1 };
 100
 101 #endif /* !NeXT */
 102
 103 #define cttyvp(p) ((p)->p_flag & P_CONTROLT ? (p)->p_session->s_ttyvp : NULL)
 104
 105 /*ARGSUSED*/
 106 int
 107 cttyopen(__unused dev_t dev, int flag, __unused int mode, struct proc *p)
 108 {
 109         struct vnode *ttyvp = cttyvp(p);
 110         struct vfs_context context;
 111         int error;
 112
 113         if (ttyvp == NULL)
 114                 return (ENXIO);
 115
 116         context.vc_proc = p;
 117         context.vc_ucred = p->p_ucred;
 118         error = VNOP_OPEN(ttyvp, flag, &context);
 119
 120         return (error);
 121 }
 122
 123 /*ARGSUSED*/
 124 int
 125 cttyread(__unused dev_t dev, struct uio *uio, int flag)
 126 {
 127         struct proc *p = current_proc();
 128         register struct vnode *ttyvp = cttyvp(p);
 129         struct vfs_context context;
 130         int error;
 131
 132         if (ttyvp == NULL)
 133                 return (EIO);
 134
 135         context.vc_proc = p;
 136         context.vc_ucred = NOCRED;
 137
 138         error = VNOP_READ(ttyvp, uio, flag, &context);
 139
 140         return (error);
 141 }
 142
 143 /*ARGSUSED*/
 144 int
 145 cttywrite(__unused dev_t dev, struct uio *uio, int flag)
 146 {
 147         struct proc *p = current_proc();
 148         register struct vnode *ttyvp = cttyvp(p);
 149         struct vfs_context context;
 150         int error;
 151
 152         if (ttyvp == NULL)
 153                 return (EIO);
 154
 155         context.vc_proc = p;
 156         context.vc_ucred = NOCRED;
 157
 158         error = VNOP_WRITE(ttyvp, uio, flag, &context);
 159
 160         return (error);
 161 }
 162
 163 /*ARGSUSED*/
 164 #ifndef NeXT
 165 static  int
 166 cttyioctl(dev, cmd, addr, flag, p)
 167         dev_t dev;
 168         int cmd;
 169         caddr_t addr;
 170         int flag;
 171         struct proc *p;
 172 #else
 173 int
 174 cttyioctl(__unused dev_t dev, u_long cmd, caddr_t addr, int flag,
 175         struct proc *p)
 176 #endif /* !NeXT */
 177 {
 178         struct vnode *ttyvp = cttyvp(p);
 179         struct vfs_context context;
 180
 181         if (ttyvp == NULL)
 182                 return (EIO);
 183         if (cmd == TIOCSCTTY)  /* don't allow controlling tty to be set    */
 184                 return EINVAL; /* to controlling tty -- infinite recursion */
 185         if (cmd == TIOCNOTTY) {
 186                 if (!SESS_LEADER(p)) {
 187                         p->p_flag &= ~P_CONTROLT;
 188                         return (0);
 189                 } else
 190                         return (EINVAL);
 191         }
 192         context.vc_proc = p;
 193         context.vc_ucred = NOCRED;
 194
 195         return (VNOP_IOCTL(ttyvp, cmd, addr, flag, &context));
 196 }
 197
 198 /*ARGSUSED*/
 199 int
 200 cttyselect(__unused dev_t dev, int flag, void* wql, struct proc *p)
 201 {
 202         struct vnode *ttyvp = cttyvp(p);
 203         struct vfs_context context;
 204
 205         context.vc_proc = p;
 206         context.vc_ucred = NOCRED;
 207
 208         if (ttyvp == NULL)
 209                 return (1);     /* try operation to get EOF/failure */
 210         return (VNOP_SELECT(ttyvp, flag, FREAD|FWRITE, wql, &context));
 211 }
 212
 213 #ifndef NeXT
 214 static ctty_devsw_installed = 0;
 215 #ifdef DEVFS
 216 static  void    *ctty_devfs_token;
 217 #endif
 218
 219 static void
 220 ctty_drvinit(void *unused)
 221 {
 222         dev_t dev;
 223
 224         if( ! ctty_devsw_installed ) {
 225                 dev = makedev(CDEV_MAJOR,0);
 226                 cdevsw_add(&dev,&ctty_cdevsw,NULL);
 227                 ctty_devsw_installed = 1;
 228 #ifdef DEVFS
 229                 ctty_devfs_token =
 230                         devfs_add_devswf(&ctty_cdevsw, 0, DV_CHR, 0, 0,
 231                                         0666, "tty");
 232 #endif
 233         }
 234 }
 235
 236 SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,ctty_drvinit,NULL)
 237
 238
 239 #endif /* !NeXT */