hurd/port2fd.c

   1 /* Copyright (C) 1994 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3
   4 The GNU C Library is free software; you can redistribute it and/or
   5 modify it under the terms of the GNU Library General Public License as
   6 published by the Free Software Foundation; either version 2 of the
   7 License, or (at your option) any later version.
   8
   9 The GNU C Library is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 Library General Public License for more details.
  13
  14 You should have received a copy of the GNU Library General Public
  15 License along with the GNU C Library; see the file COPYING.LIB.  If
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <hurd.h>
  20 #include <hurd/fd.h>
  21 #include <hurd/signal.h>
  22 #include <hurd/term.h>
  23 #include <fcntl.h>
  24
  25 /* Store PORT in file descriptor D, doing appropriate ctty magic.
  26    FLAGS are as for `open'; only O_IGNORE_CTTY is meaningful.
  27    D should be locked, and will not be unlocked.  */
  28
  29 void
  30 _hurd_port2fd (struct hurd_fd *d, io_t port, int flags)
  31 {
  32   io_t ctty;
  33   mach_port_t cttyid;
  34   int is_ctty = !(flags & O_IGNORE_CTTY) && ! __term_getctty (port, &cttyid);
  35
  36   if (is_ctty)
  37     {
  38       /* This port is capable of being a controlling tty.
  39          Is it ours?  */
  40       struct hurd_port *const id = &_hurd_ports[INIT_PORT_CTTYID];
  41       __spin_lock (&id->lock);
  42       if (id->port == MACH_PORT_NULL)
  43         /* We have no controlling tty, so make this one it.  */
  44         _hurd_port_locked_set (id, cttyid);
  45       else
  46         {
  47           if (cttyid != id->port)
  48             /* We have a controlling tty and this is not it.  */
  49             is_ctty = 0;
  50           /* Either we don't want CTTYID, or ID->port already is it.
  51              So we don't need to change ID->port, and we can release
  52              the reference to CTTYID.  */
  53           __spin_unlock (&id->lock);
  54           __mach_port_deallocate (__mach_task_self (), cttyid);
  55         }
  56     }
  57
  58   if (!is_ctty || __term_open_ctty (port, _hurd_pid, _hurd_pgrp, &ctty) != 0)
  59     /* XXX if IS_CTTY, then this port is our ctty, but we are
  60        not doing ctty style i/o because term_become_ctty barfed.
  61        What to do?  */
  62     /* No ctty magic happening here.  */
  63     ctty = MACH_PORT_NULL;
  64
  65   /* Install PORT in the descriptor cell, leaving it locked.  */
  66   {
  67     mach_port_t old
  68       = _hurd_userlink_clear (&d->port.users) ? d->port.port : MACH_PORT_NULL;
  69     d->port.port = port;
  70     if (old != MACH_PORT_NULL)
  71       __mach_port_deallocate (__mach_task_self (), old);
  72   }
  73
  74   _hurd_port_set (&d->ctty, ctty);
  75 }