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/* $OpenBSD: uthread_kill.c,v 1.7 1999/11/25 07:01:37 d Exp $ */
/*
* Copyright (c) 1997 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 AUTHOR 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.
*
* $FreeBSD: uthread_kill.c,v 1.9 1999/08/28 00:03:38 peter Exp $
*/
#include <errno.h>
#include <signal.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
pthread_kill(pthread_t pthread, int sig)
{
int ret;
/* Check for invalid signal numbers: */
if (sig < 0 || sig >= NSIG)
/* Invalid signal: */
ret = EINVAL;
/*
* Ensure the thread is in the list of active threads, and the
* signal is valid (signal 0 specifies error checking only) and
* not being ignored:
*/
else if (((ret = _find_thread(pthread)) == 0) && (sig > 0) &&
(_thread_sigact[sig - 1].sa_handler != SIG_IGN)) {
/*
* Defer signals to protect the scheduling queues from
* access by the signal handler:
*/
_thread_kern_sig_defer();
switch (pthread->state) {
case PS_SIGSUSPEND:
/*
* Only wake up the thread if the signal is unblocked
* and there is a handler installed for the signal.
*/
if (!sigismember(&pthread->sigmask, sig) &&
_thread_sigact[sig - 1].sa_handler != SIG_DFL) {
/* Change the state of the thread to run: */
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
/* Return the signal number: */
pthread->signo = sig;
}
/* Increment the pending signal count: */
sigaddset(&pthread->sigpend,sig);
break;
case PS_SIGWAIT:
/* Wake up the thread if the signal is blocked. */
if (sigismember(pthread->data.sigwait, sig)) {
/* Change the state of the thread to run: */
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
/* Return the signal number: */
pthread->signo = sig;
} else
/* Increment the pending signal count. */
sigaddset(&pthread->sigpend,sig);
break;
case PS_FDR_WAIT:
case PS_FDW_WAIT:
case PS_POLL_WAIT:
case PS_SLEEP_WAIT:
case PS_SELECT_WAIT:
if (!sigismember(&pthread->sigmask, sig) &&
(_thread_sigact[sig - 1].sa_handler != SIG_IGN)) {
/* Flag the operation as interrupted: */
pthread->interrupted = 1;
if (pthread->flags & PTHREAD_FLAGS_IN_WORKQ)
PTHREAD_WORKQ_REMOVE(pthread);
/* Change the state of the thread to run: */
PTHREAD_NEW_STATE(pthread,PS_RUNNING);
/* Return the signal number: */
pthread->signo = sig;
} else {
/* Increment the pending signal count: */
sigaddset(&pthread->sigpend,sig);
}
break;
default:
/* Increment the pending signal count: */
sigaddset(&pthread->sigpend,sig);
break;
}
/*
* Check that a custom handler is installed
* and if the signal is not blocked:
*/
if (_thread_sigact[sig - 1].sa_handler != SIG_DFL &&
_thread_sigact[sig - 1].sa_handler != SIG_IGN &&
sigismember(&pthread->sigpend, sig) &&
!sigismember(&pthread->sigmask, sig)) {
pthread_t pthread_saved = _thread_run;
/* Current thread inside critical region? */
if (_thread_run->sig_defer_count > 0)
pthread->sig_defer_count++;
_thread_run = pthread;
/* Clear the pending signal: */
sigdelset(&pthread->sigpend, sig);
/*
* Dispatch the signal via the custom signal
* handler:
*/
(*(_thread_sigact[sig - 1].sa_handler))(sig);
_thread_run = pthread_saved;
if (_thread_run->sig_defer_count > 0)
pthread->sig_defer_count--;
}
/*
* Undefer and handle pending signals, yielding if
* necessary:
*/
_thread_kern_sig_undefer();
}
/* Return the completion status: */
return (ret);
}
#endif
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