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/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <signal.h>
#include <errno.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
sigaction(int sig, const struct sigaction * act, struct sigaction * oact)
{
int ret = 0;
struct sigaction gact;
/* Check if the signal number is out of range: */
if (sig < 1 || sig > NSIG) {
/* Return an invalid argument: */
errno = EINVAL;
ret = -1;
} else {
/*
* Check if the existing signal action structure contents are
* to be returned:
*/
if (oact != NULL) {
/* Return the existing signal action contents: */
oact->sa_handler = _thread_sigact[sig - 1].sa_handler;
oact->sa_mask = _thread_sigact[sig - 1].sa_mask;
oact->sa_flags = _thread_sigact[sig - 1].sa_flags;
}
/* Check if a signal action was supplied: */
if (act != NULL) {
/* Set the new signal handler: */
_thread_sigact[sig - 1].sa_mask = act->sa_mask;
_thread_sigact[sig - 1].sa_flags = act->sa_flags;
_thread_sigact[sig - 1].sa_handler = act->sa_handler;
}
/*
* Check if the kernel needs to be advised of a change
* in signal action:
*/
if (act != NULL && sig != SIGVTALRM && sig != SIGCHLD &&
sig != SIGINFO) {
/* Initialise the global signal action structure: */
gact.sa_mask = act->sa_mask;
gact.sa_flags = act->sa_flags | SA_RESTART;
/*
* Check if the signal handler is being set to
* the default or ignore handlers:
*/
if (act->sa_handler == SIG_DFL ||
act->sa_handler == SIG_IGN)
/* Specify the built in handler: */
gact.sa_handler = act->sa_handler;
else
/*
* Specify the thread kernel signal
* handler:
*/
gact.sa_handler = (void (*) ()) _thread_sig_handler;
/* Change the signal action in the kernel: */
if (_thread_sys_sigaction(sig,&gact,NULL) != 0)
ret = -1;
}
}
/* Return the completion status: */
return (ret);
}
#endif
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