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/*
* Copyright (c) 1998 Daniel M. Eischen <eischen@vigrid.com>
* 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 <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <pthread.h>
#include <signal.h>
#include <string.h>
static int sigcounts[NSIG + 1];
static sigset_t wait_mask;
static void *
sigwaiter (void *arg)
{
int signo;
while (sigcounts[SIGINT] == 0) {
if (sigwait (&wait_mask, &signo) != 0) {
printf ("Unable to wait for signal, errno %d\n",
errno);
exit (1);
}
sigcounts[signo]++;
printf ("Sigwait caught signal %d\n", signo);
}
pthread_exit (arg);
return (NULL);
}
static void
sighandler (int signo)
{
printf ("Signal handler caught signal %d\n", signo);
if ((signo >= 0) && (signo <= NSIG))
sigcounts[signo]++;
}
static void
send_thread_signal (pthread_t tid, int signo)
{
if (pthread_kill (tid, signo) != 0) {
printf ("Unable to send thread signal, errno %d.\n", errno);
exit (1);
}
}
static void
send_process_signal (int signo)
{
if (kill (getpid (), signo) != 0) {
printf ("Unable to send process signal, errno %d.\n", errno);
exit (1);
}
}
int main (int argc, char *argv[])
{
pthread_attr_t pattr;
pthread_t tid;
void * exit_status;
struct sigaction act;
/* Initialize our signal counts. */
memset ((void *) sigcounts, 0, NSIG * sizeof (int));
/* Setupt our wait mask. */
sigemptyset (&wait_mask); /* Default action */
sigaddset (&wait_mask, SIGINT); /* terminate */
sigaddset (&wait_mask, SIGHUP); /* terminate */
sigaddset (&wait_mask, SIGQUIT); /* create core image */
sigaddset (&wait_mask, SIGURG); /* ignore */
sigaddset (&wait_mask, SIGIO); /* ignore */
sigaddset (&wait_mask, SIGUSR1); /* terminate */
/* Ignore signal SIGIO. */
sigemptyset (&act.sa_mask);
sigaddset (&act.sa_mask, SIGIO);
act.sa_handler = SIG_IGN;
act.sa_flags = 0;
sigaction (SIGIO, &act, NULL);
/* Install a signal handler for SIGURG */
sigemptyset (&act.sa_mask);
sigaddset (&act.sa_mask, SIGURG);
act.sa_handler = sighandler;
act.sa_flags = SA_RESTART;
sigaction (SIGURG, &act, NULL);
/* Install a signal handler for SIGXCPU */
sigemptyset (&act.sa_mask);
sigaddset (&act.sa_mask, SIGXCPU);
sigaction (SIGXCPU, &act, NULL);
/*
* Initialize the thread attribute.
*/
if ((pthread_attr_init (&pattr) != 0) ||
(pthread_attr_setdetachstate (&pattr,
PTHREAD_CREATE_JOINABLE) != 0)) {
printf ("Unable to initialize thread attributes.\n");
exit (1);
}
/*
* Create the sigwaiter thread.
*/
if (pthread_create (&tid, &pattr, sigwaiter, NULL) != 0) {
printf ("Unable to create thread, errno %d.\n", errno);
exit (1);
}
/*
* Verify that an ignored signal doesn't cause a wakeup.
* We don't have a handler installed for SIGIO.
*/
printf ("Sending pthread_kill SIGIO.\n");
send_thread_signal (tid, SIGIO);
sleep (1);
printf ("Sending kill SIGIO.\n");
send_process_signal (SIGIO);
sleep (1);
if (sigcounts[SIGIO] != 0)
printf ("FAIL: sigwait wakes up for ignored signal SIGIO.\n");
/*
* Verify that a signal with a default action of ignore, for
* which we have a signal handler installed, will release a sigwait.
*/
send_thread_signal (tid, SIGURG);
sleep (1);
send_process_signal (SIGURG);
sleep (1);
if (sigcounts[SIGURG] != 2)
printf ("FAIL: sigwait doesn't wake up for SIGURG.\n");
/*
* Verify that a signal with a default action that terminates
* the process will release a sigwait.
*/
send_thread_signal (tid, SIGUSR1);
sleep (1);
send_process_signal (SIGUSR1);
sleep (1);
if (sigcounts[SIGUSR1] != 2)
printf ("FAIL: sigwait doesn't wake up for SIGUSR1.\n");
/*
* Verify that we can still kill the process for a signal
* not being waited on by sigwait.
*/
send_process_signal (SIGPIPE);
printf ("FAIL: SIGPIPE did not terminate process.\n");
/*
* Wait for the thread to finish.
*/
pthread_join (tid, &exit_status);
return (0);
}
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