glibc/hurd/preempt-sig.c
1995-02-18 01:27:10 +00:00

69 lines
2.2 KiB
C

/* Copyright (C) 1994 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 <hurd/signal.h>
/* Initialize PREEMPTER with the information given and stick it in the
chain of preempters for SIGNO. */
int
hurd_preempt_signals (struct hurd_signal_preempt *preempter,
int signo, int first_code, int last_code,
sighandler_t (*handler) (thread_t, int, long int, int))
{
if (signo <= 0 || signo >= NSIG)
{
errno = EINVAL;
return -1;
}
preempter->first = first_code;
preempter->last = last_code;
preempter->handler = handler;
__mutex_lock (&_hurd_signal_preempt_lock);
preempter->next = _hurd_signal_preempt[signo];
_hurd_signal_preempt[signo] = preempter;
__mutex_unlock (&_hurd_signal_preempt_lock);
return 0;
}
/* Remove PREEMPTER from the chain for SIGNO. */
int
hurd_unpreempt_signals (struct hurd_signal_preempt *preempter, int signo)
{
struct hurd_signal_preempt *p, *lastp;
if (signo <= 0 || signo >= NSIG)
{
errno = EINVAL;
return -1;
}
__mutex_lock (&_hurd_signal_preempt_lock);
for (p = _hurd_signal_preempt[signo], lastp = NULL;
p != NULL; lastp = p, p = p->next)
if (p == preempter)
{
(lastp == NULL ? _hurd_signal_preempt[signo] : lastp->next) = p->next;
__mutex_unlock (&_hurd_signal_preempt_lock);
return 0;
}
_hurd_signal_preempt[signo] = preempter;
__mutex_unlock (&_hurd_signal_preempt_lock);
errno = ENOENT;
return -1;
}