diff options
Diffstat (limited to 'sysdeps/mach/hurd/sigsuspend.c')
-rw-r--r-- | sysdeps/mach/hurd/sigsuspend.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/mach/hurd/sigsuspend.c b/sysdeps/mach/hurd/sigsuspend.c new file mode 100644 index 0000000000..aa0b2876a4 --- /dev/null +++ b/sysdeps/mach/hurd/sigsuspend.c @@ -0,0 +1,81 @@ +/* Copyright (C) 1991, 1992, 1993, 1994, 1995 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 Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <ansidecl.h> +#include <errno.h> +#include <hurd.h> +#include <hurd/signal.h> +#include <hurd/msg.h> + +/* Change the set of blocked signals to SET, + wait until a signal arrives, and restore the set of blocked signals. */ +int +DEFUN(sigsuspend, (set), CONST sigset_t *set) +{ + struct hurd_sigstate *ss; + sigset_t newmask, oldmask, pending; + mach_port_t wait; + mach_msg_header_t msg; + + if (set != NULL) + /* Crash before locking. */ + newmask = *set; + + /* Get a fresh port we will wait on. */ + wait = __mach_reply_port (); + + ss = _hurd_self_sigstate (); + + __spin_lock (&ss->lock); + + oldmask = ss->blocked; + if (set != NULL) + /* Change to the new blocked signal mask. */ + ss->blocked = newmask & ~_SIG_CANT_MASK; + + /* Notice if any pending signals just became unblocked. */ + pending = ss->pending & ~ss->blocked; + + /* Tell the signal thread to message us when a signal arrives. */ + ss->suspended = wait; + __spin_unlock (&ss->lock); + + if (pending) + /* Tell the signal thread to check for pending signals. */ + __msg_sig_post (_hurd_msgport, 0, __mach_task_self ()); + + /* Wait for the signal thread's message. */ + __mach_msg (&msg, MACH_RCV_MSG, 0, sizeof (msg), wait, + MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL); + __mach_port_destroy (__mach_task_self (), wait); + + __spin_lock (&ss->lock); + ss->blocked = oldmask; /* Restore the old mask. */ + pending = ss->pending & ~ss->blocked; /* Again check for pending signals. */ + __spin_unlock (&ss->lock); + + if (pending) + /* Tell the signal thread to check for pending signals. */ + __msg_sig_post (_hurd_msgport, 0, __mach_task_self ()); + + /* We've been interrupted! And a good thing, too. + Otherwise we'd never return. + That's right; this function always returns an error. */ + errno = EINTR; + return -1; +} |