1: /* _hurd_ctty_input -- Do an input RPC and generate SIGTTIN if necessary.
    2:    Copyright (C) 1995,97,99 Free Software Foundation, Inc.
    3:    This file is part of the GNU C Library.
    4: 
    5:    The GNU C Library is free software; you can redistribute it and/or
    6:    modify it under the terms of the GNU Lesser General Public
    7:    License as published by the Free Software Foundation; either
    8:    version 2.1 of the License, or (at your option) any later version.
    9: 
   10:    The GNU C Library is distributed in the hope that it will be useful,
   11:    but WITHOUT ANY WARRANTY; without even the implied warranty of
   12:    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   13:    Lesser General Public License for more details.
   14: 
   15:    You should have received a copy of the GNU Lesser General Public
   16:    License along with the GNU C Library; if not, write to the Free
   17:    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   18:    02111-1307 USA.  */
   19: 
   20: #include <hurd.h>
   21: #include <hurd/signal.h>
   22: 
   23: /* Call *RPC on PORT and/or CTTY.  If a call on CTTY returns EBACKGROUND,
   24:    generate SIGTTIN or EIO as appropriate.  */
   25: 
   26: error_t
   27: _hurd_ctty_input (io_t port, io_t ctty, error_t (*rpc) (io_t))
   28: {
   29:   error_t err;
   30: 
   31:   if (ctty == MACH_PORT_NULL)
   32:     return (*rpc) (port);
   33: 
   34:   do
   35:     {
   36:       err = (*rpc) (ctty);
   37:       if (err == EBACKGROUND)
   38:         {
   39:           /* We are a background job and tried to read from the tty.
   40:              We should probably get a SIGTTIN signal.  */
   41:           if (_hurd_orphaned)
   42:             /* Our process group is orphaned.  Don't stop; just fail.  */
   43:             err = EIO;
   44:           else
   45:             {
   46:               struct hurd_sigstate *ss = _hurd_self_sigstate ();
   47:               __spin_lock (&ss->lock);
   48:               if (__sigismember (&ss->blocked, SIGTTIN) ||
   49:                   ss->actions[SIGTTIN].sa_handler == SIG_IGN)
   50:                 /* We are blocking or ignoring SIGTTIN.  Just fail.  */
   51:                 err = EIO;
   52:               __spin_unlock (&ss->lock);
   53: 
   54:               if (err == EBACKGROUND)
   55:                 {
   56:                   /* Send a SIGTTIN signal to our process group.
   57: 
   58:                      We must remember here not to clobber ERR, since
   59:                      the loop condition below uses it to recall that
   60:                   we should retry after a stop.  */
   61: 
   62:                   __USEPORT (CTTYID, _hurd_sig_post (0, SIGTTIN, port));
   63:                   /* XXX what to do if error here? */
   64: 
   65:                   /* At this point we should have just run the handler for
   66:                      SIGTTIN or resumed after being stopped.  Now this is
   67:                      still a "system call", so check to see if we should
   68:                   restart it.  */
   69:                   __spin_lock (&ss->lock);
   70:                   if (!(ss->actions[SIGTTIN].sa_flags & SA_RESTART))
   71:                     err = EINTR;
   72:                   __spin_unlock (&ss->lock);
   73:                 }
   74:             }
   75:         }
   76:       /* If the last RPC generated a SIGTTIN, loop to try it again.  */
   77:     } while (err == EBACKGROUND);
   78: 
   79:   return err;
   80: }