/****************************************************************************
* apps/examples/ostest/signest.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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 <sys/types.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <semaphore.h>
#include <signal.h>
#include <sched.h>
#include <errno.h>
#include "ostest.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef NULL
# define NULL (void*)0
#endif
#define WAKEUP_SIGNAL 17
#define SIGVALUE_INT 42
/****************************************************************************
* Private Data
****************************************************************************/
static sem_t g_waiter_sem;
static sem_t g_interferer_sem;
static volatile bool g_waiter_running;
static volatile bool g_interferer_running;
static volatile bool g_done;
static volatile int g_nestlevel;
static volatile int g_even_handled;
static volatile int g_odd_handled;
static volatile int g_even_nested;
static volatile int g_odd_nested;
static volatile int g_nest_level;
/****************************************************************************
* Private Functions
****************************************************************************/
static void waiter_action(int signo)
{
int nest_level;
sched_lock();
nest_level = g_nest_level++;
sched_unlock();
if ((signo & 1) != 0)
{
g_odd_handled++;
if (nest_level > 0)
{
g_odd_nested++;
}
}
else
{
g_even_handled++;
if (nest_level > 0)
{
g_even_nested++;
}
}
g_nest_level = nest_level;
}
static int waiter_main(int argc, char *argv[])
{
sigset_t set;
struct sigaction act;
int ret;
int i;
printf("waiter_main: Waiter started\n" );
printf("waiter_main: Setting signal mask\n" );
(void)sigemptyset(&set);
ret = sigprocmask(SIG_SETMASK, &set, NULL);
if (ret < 0)
{
printf("waiter_main: ERROR sigprocmask failed: %d\n", errno);
return EXIT_FAILURE;
}
printf("waiter_main: Registering signal handler\n" );
act.sa_handler = waiter_action;
act.sa_flags = 0;
(void)sigemptyset(&act.sa_mask);
for (i = 1; i < MAX_SIGNO; i += 2)
{
(void)sigaddset(&act.sa_mask, i);
}
for (i = 1; i < MAX_SIGNO; i++)
{
ret = sigaction(i, &act, NULL);
if (ret < 0)
{
printf("waiter_main: ERROR sigaction failed\n" , errno);
return EXIT_FAILURE;
}
}
/* Now just loop until the test completes */
printf("waiter_main: Waiting on semaphore\n" );
FFLUSH();
g_waiter_running = true;
while (!g_done)
{
ret = sem_wait(&g_waiter_sem);
}
/* Just exit, the system should clean up the signal handlers */
g_waiter_running = false;
return EXIT_SUCCESS;
}
static int interfere_main(int argc, char *argv[])
{
/* Now just loop staying in the way as much as possible */
printf("interfere_main: Waiting on semaphore\n" );
FFLUSH();
g_interferer_running = true;
while (!g_done)
{
(void)sem_wait(&g_interferer_sem);
}
/* Just exit, the system should clean up the signal handlers */
g_interferer_running = false;
return EXIT_SUCCESS;
}
/****************************************************************************
* Public Functions
****************************************************************************/
void signest_test(void)
{
struct sched_param param;
pid_t waiterpid;
pid_t interferepid;
int total_signals;
int total_handled;
int total_nested;
int even_signals;
int odd_signals;
int prio;
int ret;
int i;
int j;
sem_init(&g_waiter_sem, 0, 0);
sem_init(&g_interferer_sem, 0, 0);
g_waiter_running = false;
g_interferer_running = false;
g_done = false;
g_nestlevel = 0;
even_signals = 0;
odd_signals = 0;
g_even_handled = 0;
g_odd_handled = 0;
g_even_nested = 0;
g_odd_nested = 0;
g_nest_level = 0;
ret = sched_getparam (0, ¶m);
if (ret < 0)
{
printf("signest_test: ERROR sched_getparam() failed\n" );
param.sched_priority = PTHREAD_DEFAULT_PRIORITY;
}
/* Start waiter thread */
prio = param.sched_priority + 1;
printf("signest_test: Starting signal waiter task at priority %d\n", prio);
waiterpid = task_create("waiter", param.sched_priority,
PTHREAD_STACK_DEFAULT, waiter_main, NULL);
if (waiterpid == ERROR)
{
printf("signest_test: ERROR failed to start waiter_main\n");
return;
}
printf("signest_test: Started waiter_main pid=%d\n", waiterpid);
/* Start interfering thread */
prio++;
printf("signest_test: Starting interfering task at priority %d\n", prio);
interferepid = task_create("interfere", param.sched_priority,
PTHREAD_STACK_DEFAULT, interfere_main, NULL);
if (interferepid == ERROR)
{
printf("signest_test: ERROR failed to start interfere_main\n");
goto errout_with_waiter;
}
printf("signest_test: Started interfere_main pid=%d\n", interferepid);
/* Wait a bit */
FFLUSH();
usleep(500*1000L);
/* Then signal the waiter thread with back-to-back signals, one masked and the other unmasked. */
for (i = 0; i < 10; i++)
{
for (j = 1; j < MAX_SIGNO; j += 2)
{
/* Odd then even */
kill(waiterpid, j);
kill(waiterpid, j+1);
odd_signals++;
even_signals++;
usleep(10*1000L);
/* Even then odd */
kill(waiterpid, j+1);
kill(waiterpid, j);
odd_signals++;
even_signals++;
usleep(10*1000L);
}
}
/* Check the test results so far */
total_signals = odd_signals + even_signals;
total_handled = g_odd_handled + g_even_handled;
total_nested = g_odd_nested + g_even_nested;
printf("signest_test: Simple case:\n");
printf(" Total signalled %-3d Odd=%-3d Even=%-3d\n",
total_signals, odd_signals, even_signals);
printf(" Total handled %-3d Odd=%-3d Even=%-3d\n",
total_handled, g_odd_handled, g_even_handled);
printf(" Total nested %-3d Odd=%-3d Even=%-3d\n",
total_nested, g_odd_nested, g_even_nested);
/* Then signal the waiter thread with two signals pending. The
* sched_lock() assures that the first signal was not processed
* before the second was delivered.
*/
for (i = 0; i < 10; i++)
{
for (j = 1; j < MAX_SIGNO; j += 2)
{
/* Odd then even */
sched_lock();
kill(waiterpid, j);
kill(waiterpid, j+1);
odd_signals++;
even_signals++;
sched_unlock();
usleep(10*1000L);
/* Even then odd */
sched_lock();
kill(waiterpid, j+1);
kill(waiterpid, j);
odd_signals++;
even_signals++;
sched_unlock();
usleep(10*1000L);
}
}
/* Check the test results so far */
total_signals = odd_signals + even_signals;
total_handled = g_odd_handled + g_even_handled;
total_nested = g_odd_nested + g_even_nested;
printf("signest_test: With task locking\n");
printf(" Total signalled %-3d Odd=%-3d Even=%-3d\n",
total_signals, odd_signals, even_signals);
printf(" Total handled %-3d Odd=%-3d Even=%-3d\n",
total_handled, g_odd_handled, g_even_handled);
printf(" Total nested %-3d Odd=%-3d Even=%-3d\n",
total_nested, g_odd_nested, g_even_nested);
/* Then do it all over again with the interfering thread. */
for (i = 0; i < 10; i++)
{
for (j = 1; j < MAX_SIGNO; j += 2)
{
/* Odd then even */
sched_lock();
kill(waiterpid, j);
sem_post(&g_interferer_sem);
kill(waiterpid, j+1);
odd_signals++;
even_signals++;
sched_unlock();
usleep(10*1000L);
/* Even then odd */
sched_lock();
kill(waiterpid, j+1);
sem_post(&g_interferer_sem);
kill(waiterpid, j);
odd_signals++;
even_signals++;
sched_unlock();
usleep(10*1000L);
}
}
/* Stop the threads */
errout_with_waiter:
g_done = true;
sem_post(&g_waiter_sem);
sem_post(&g_interferer_sem);
usleep(500*1000L);
/* Check the final test results */
total_signals = odd_signals + even_signals;
total_handled = g_odd_handled + g_even_handled;
total_nested = g_odd_nested + g_even_nested;
printf("signest_test: With intefering thread\n");
printf(" Total signalled %-3d Odd=%-3d Even=%-3d\n",
total_signals, odd_signals, even_signals);
printf(" Total handled %-3d Odd=%-3d Even=%-3d\n",
total_handled, g_odd_handled, g_even_handled);
printf(" Total nested %-3d Odd=%-3d Even=%-3d\n",
total_nested, g_odd_nested, g_even_nested);
/* Check for error */
if (g_waiter_running)
{
printf("signest_test: ERROR waiter is still running\n");
}
if (g_interferer_running)
{
printf("signest_test: ERROR interferer is still running\n");
}
if (total_signals != total_handled)
{
printf("signest_test: ERROR only %d of %d signals were handled\n",
total_handled, total_signals);
}
if (odd_signals != g_odd_handled)
{
printf("signest_test: ERROR only %d of %d ODD signals were handled\n",
g_odd_handled, odd_signals);
}
if (even_signals != g_even_handled)
{
printf("signest_test: ERROR only %d of %d EVEN signals were handled\n",
g_even_handled, even_signals);
}
if (g_odd_nested > 0)
{
printf("signest_test: ERROR %d ODD signals were nested\n",
g_odd_nested);
}
sem_destroy(&g_waiter_sem);
sem_destroy(&g_interferer_sem);
printf("signest_test: done\n" );
FFLUSH();
}