The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/kern/tty_tty.c

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * Copyright (c) 2003 Poul-Henning Kamp.  All rights reserved.
    3  *
    4  * Redistribution and use in source and binary forms, with or without
    5  * modification, are permitted provided that the following conditions
    6  * are met:
    7  * 1. Redistributions of source code must retain the above copyright
    8  *    notice, this list of conditions and the following disclaimer.
    9  * 2. Redistributions in binary form must reproduce the above copyright
   10  *    notice, this list of conditions and the following disclaimer in the
   11  *    documentation and/or other materials provided with the distribution.
   12  *
   13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   23  * SUCH DAMAGE.
   24  */
   25 
   26 #include <sys/cdefs.h>
   27 __FBSDID("$FreeBSD: releng/8.0/sys/kern/tty_tty.c 179519 2008-06-03 12:38:00Z ed $");
   28 
   29 #include <sys/param.h>
   30 #include <sys/systm.h>
   31 #include <sys/conf.h>
   32 #include <sys/kernel.h>
   33 #include <sys/proc.h>
   34 #include <sys/sx.h>
   35 #include <sys/vnode.h>
   36 
   37 #include <fs/devfs/devfs.h>
   38 #include <fs/devfs/devfs_int.h>
   39 
   40 static  d_open_t        cttyopen;
   41 
   42 static struct cdevsw ctty_cdevsw = {
   43         .d_version =    D_VERSION,
   44         .d_open =       cttyopen,
   45         .d_name =       "ctty",
   46 };
   47 
   48 static struct cdev *ctty;
   49 
   50 static  int
   51 cttyopen(struct cdev *dev, int flag, int mode, struct thread *td)
   52 {
   53 
   54         return (ENXIO);
   55 }
   56 
   57 static void
   58 ctty_clone(void *arg, struct ucred *cred, char *name, int namelen,
   59     struct cdev **dev)
   60 {
   61 
   62         if (*dev != NULL)
   63                 return;
   64         if (strcmp(name, "tty"))
   65                 return;
   66         sx_sunlock(&clone_drain_lock);
   67         sx_slock(&proctree_lock);
   68         sx_slock(&clone_drain_lock);
   69         dev_lock();
   70         if (!(curthread->td_proc->p_flag & P_CONTROLT))
   71                 *dev = ctty;
   72         else if (curthread->td_proc->p_session->s_ttyvp == NULL)
   73                 *dev = ctty;
   74         else if (curthread->td_proc->p_session->s_ttyvp->v_type == VBAD ||
   75             curthread->td_proc->p_session->s_ttyvp->v_rdev == NULL) {
   76                 /* e.g. s_ttyvp was revoked */
   77                 *dev = ctty;
   78         } else
   79                 *dev = curthread->td_proc->p_session->s_ttyvp->v_rdev;
   80         dev_refl(*dev);
   81         dev_unlock();
   82         sx_sunlock(&proctree_lock);
   83 }
   84 
   85 static void
   86 ctty_drvinit(void *unused)
   87 {
   88 
   89         EVENTHANDLER_REGISTER(dev_clone, ctty_clone, 0, 1000);
   90         ctty = make_dev(&ctty_cdevsw, 0, 0, 0, 0666, "ctty");
   91 }
   92 
   93 SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE,ctty_drvinit,NULL);

Cache object: 9f253901d5fe3721de330ca7ec16f2fb


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.