/*
 * 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 Daniel M. Eischen.
 * 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 DANIEL M. EISCHEN 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.
 *
 * $FreeBSD: src/lib/libc_r/test/sigsuspend_d.c,v 1.1.2.1 2000/07/17 22:18:32 jasone Exp $
 */
#include <stdlib.h>
#include <unistd.h>

#include <errno.h>
#include <pthread.h>
#include <pthread_np.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>

static int      sigcounts[NSIG + 1];
static int      sigfifo[NSIG + 1];
static int      fifo_depth = 0;
static sigset_t suspender_mask;
static pthread_t suspender_tid;


static void *
sigsuspender (void *arg)
{
        int status, i;
        sigset_t run_mask;

        /* Run with all signals blocked. */
        sigfillset (&run_mask);
        sigprocmask (SIG_SETMASK, &run_mask, NULL);

        /* Allow these signals to wake us up during a sigsuspend. */
        sigfillset (&suspender_mask);           /* Default action       */
        sigdelset (&suspender_mask, SIGINT);    /* terminate            */
        sigdelset (&suspender_mask, SIGHUP);    /* terminate            */
        sigdelset (&suspender_mask, SIGQUIT);   /* create core image    */
        sigdelset (&suspender_mask, SIGURG);    /* ignore               */
        sigdelset (&suspender_mask, SIGIO);     /* ignore               */
        sigdelset (&suspender_mask, SIGUSR2);   /* terminate            */

        while (sigcounts[SIGINT] == 0) {
                status = sigsuspend (&suspender_mask);
                if ((status == 0) || (errno != EINTR)) {
                        fprintf (stderr, "Unable to suspend for signals, "
                                "errno %d, return value %d\n",
                                errno, status);
                        exit (1);
                }
                for (i = 0; i < fifo_depth; i++)
                        fprintf (stderr, "Sigsuspend woke up by signal %d\n",
                                sigfifo[i]);
                fifo_depth = 0;
        }

        pthread_exit (arg);
        return (NULL);
}


static void
sighandler (int signo)
{
        sigset_t set, suspend_set;
        pthread_t self;

        if ((signo >= 0) && (signo <= NSIG))
                sigcounts[signo]++;

        /*
         * If we are running on behalf of the suspender thread,
         * ensure that we have the correct mask set.
         */
        self = pthread_self ();
        if (self == suspender_tid) {
                sigfifo[fifo_depth] = signo;
                fifo_depth++;
                fprintf (stderr,
                    "  -> Suspender thread signal handler caught signal %d\n",
                    signo);

                /* Get the current signal mask. */
                sigprocmask (SIG_SETMASK, NULL, &set);

                /* The handler should run with the current signal masked. */
                suspend_set = suspender_mask;
                sigaddset(&suspend_set, signo);

                if (memcmp(&set, &suspend_set, sizeof(set)))
                        fprintf (stderr,
                            "  >>> FAIL: sigsuspender signal handler running "
                            "with incorrect mask.\n");
        }
        else
                fprintf (stderr,
                    "  -> Main thread signal handler caught signal %d\n",
                    signo);
}


static void
send_thread_signal (pthread_t tid, int signo)
{
        if (pthread_kill (tid, signo) != 0) {
                fprintf (stderr, "Unable to send thread signal, errno %d.\n",
                    errno);
                exit (1);
        }
}


static void
send_process_signal (int signo)
{
        if (kill (getpid (), signo) != 0) {
                fprintf (stderr, "Unable to send process signal, errno %d.\n",
                    errno);
                exit (1);
        }
}


int main (int argc, char *argv[])
{
        pthread_attr_t  pattr;
        void *          exit_status;
        struct sigaction act;
        sigset_t        oldset;
        sigset_t        newset;

        /* Initialize our signal counts. */
        memset ((void *) sigcounts, 0, NSIG * sizeof (int));

        /* 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);

        /* Get our current signal mask. */
        sigprocmask (SIG_SETMASK, NULL, &oldset);

        /* Mask out SIGUSR1 and SIGUSR2. */
        newset = oldset;
        sigaddset (&newset, SIGUSR1);
        sigaddset (&newset, SIGUSR2);
        sigprocmask (SIG_SETMASK, &newset, NULL);

        /* Install a signal handler for SIGUSR1 */
        sigemptyset (&act.sa_mask);
        sigaddset (&act.sa_mask, SIGUSR1);
        sigaction (SIGUSR1, &act, NULL);

        /* Install a signal handler for SIGUSR2 */
        sigemptyset (&act.sa_mask);
        sigaddset (&act.sa_mask, SIGUSR2);
        sigaction (SIGUSR2, &act, NULL);

        /*
         * Initialize the thread attribute.
         */
        if ((pthread_attr_init (&pattr) != 0) ||
            (pthread_attr_setdetachstate (&pattr,
            PTHREAD_CREATE_JOINABLE) != 0)) {
                fprintf (stderr, "Unable to initialize thread attributes.\n");
                exit (1);
        }

        /*
         * Create the sigsuspender thread.
         */
        if (pthread_create (&suspender_tid, &pattr, sigsuspender, NULL) != 0) {
                fprintf (stderr, "Unable to create thread, errno %d.\n", errno);
                exit (1);
        }
        pthread_set_name_np (suspender_tid, "sigsuspender");

        /*
         * Verify that an ignored signal doesn't cause a wakeup.
         * We don't have a handler installed for SIGIO.
         */
        send_thread_signal (suspender_tid, SIGIO);
        sleep (1);
        send_process_signal (SIGIO);
        sleep (1);
        if (sigcounts[SIGIO] != 0)
                fprintf (stderr, "FAIL: sigsuspend 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
         * sigsuspend.
         */
        send_thread_signal (suspender_tid, SIGURG);
        sleep (1);
        send_process_signal (SIGURG);
        sleep (1);
        if (sigcounts[SIGURG] != 2)
                fprintf (stderr,
                    "FAIL: sigsuspend doesn't wake up for SIGURG.\n");

        /*
         * Verify that a SIGUSR2 signal will release a sigsuspended
         * thread.
         */
        send_thread_signal (suspender_tid, SIGUSR2);
        sleep (1);
        send_process_signal (SIGUSR2);
        sleep (1);
        if (sigcounts[SIGUSR2] != 2)
                fprintf (stderr,
                    "FAIL: sigsuspend doesn't wake up for SIGUSR2.\n");

        /*
         * Verify that a signal, blocked in both the main and
         * sigsuspender threads, does not cause the signal handler
         * to be called.
         */
        send_thread_signal (suspender_tid, SIGUSR1);
        sleep (1);
        send_process_signal (SIGUSR1);
        sleep (1);
        if (sigcounts[SIGUSR1] != 0)
                fprintf (stderr, "FAIL: signal hander called for SIGUSR1.\n");

        /*
         * Verify that we can still kill the process for a signal
         * not being waited on by sigwait.
         */
        send_process_signal (SIGPIPE);
        fprintf (stderr, "FAIL: SIGPIPE did not terminate process.\n");

        /*
         * Wait for the thread to finish.
         */
        pthread_join (suspender_tid, &exit_status);

        return (0);
}