| /* _hurd_ctty_output -- Do an output RPC and generate SIGTTOU if necessary. |
| Copyright (C) 1995-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <hurd.h> |
| #include <hurd/signal.h> |
| |
| /* Call *RPC on PORT and/or CTTY. If a call on CTTY returns EBACKGROUND, |
| generate SIGTTOU if appropriate. */ |
| |
| error_t |
| _hurd_ctty_output (io_t port, io_t ctty, error_t (*rpc) (io_t)) |
| { |
| if (ctty == MACH_PORT_NULL) |
| return (*rpc) (port); |
| else |
| { |
| struct hurd_sigstate *ss = _hurd_self_sigstate (); |
| error_t err; |
| |
| do |
| { |
| /* Don't use the ctty io port if we are blocking or ignoring |
| SIGTTOU. We redo this check at the top of the loop in case |
| the signal handler changed the state. */ |
| __spin_lock (&ss->lock); |
| if (__sigismember (&ss->blocked, SIGTTOU) || |
| ss->actions[SIGTTOU].sa_handler == SIG_IGN) |
| err = EIO; |
| else |
| err = 0; |
| __spin_unlock (&ss->lock); |
| |
| if (err) |
| return (*rpc) (port); |
| |
| err = (*rpc) (ctty); |
| if (err == EBACKGROUND) |
| { |
| if (_hurd_orphaned) |
| /* Our process group is orphaned, so we never generate a |
| signal; we just fail. */ |
| err = EIO; |
| else |
| { |
| /* Send a SIGTTOU signal to our process group. |
| |
| We must remember here not to clobber ERR, since |
| the loop condition below uses it to recall that |
| we should retry after a stop. */ |
| |
| __USEPORT (CTTYID, _hurd_sig_post (0, SIGTTOU, port)); |
| /* XXX what to do if error here? */ |
| |
| /* At this point we should have just run the handler for |
| SIGTTOU or resumed after being stopped. Now this is |
| still a "system call", so check to see if we should |
| restart it. */ |
| __spin_lock (&ss->lock); |
| if (!(ss->actions[SIGTTOU].sa_flags & SA_RESTART)) |
| err = EINTR; |
| __spin_unlock (&ss->lock); |
| } |
| } |
| /* If the last RPC generated a SIGTTOU, loop to try it again. */ |
| } while (err == EBACKGROUND); |
| |
| return err; |
| } |
| } |
