/*
 * This file is distributed as part of MaxScale.  It is free
 * software: you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation,
 * version 2.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Copyright MariaDB Corporation Ab 2014
 */

/**
 *
 * @verbatim
 * Revision History
 *
 * Date		Who			Description
 * 18/08-2014	Mark Riddoch		Initial implementation
 *
 * @endverbatim
 */

// To ensure that ss_info_assert asserts also when builing in non-debug mode.
#if !defined(SS_DEBUG)
#define SS_DEBUG
#endif
#if defined(NDEBUG)
#undef NDEBUG
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <spinlock.h>
#include <thread.h>


/**
 * test1	spinlock_acquire_nowait tests
 *
 * Test that spinlock_acquire_nowait returns false if the spinlock
 * is already taken.
 *
 * Test that spinlock_acquire_nowait returns true if the spinlock
 * is not taken.
 *
 * Test that spinlock_acquire_nowait does hold the spinlock.
 */
static int
test1()
{
SPINLOCK	lck;

	spinlock_init(&lck);
	spinlock_acquire(&lck);
	if (spinlock_acquire_nowait(&lck))
	{
		fprintf(stderr, "spinlock_acquire_nowait: test 1.1 failed.\n");
		return 1;
	}
	spinlock_release(&lck);
	if (!spinlock_acquire_nowait(&lck))
	{
		fprintf(stderr, "spinlock_acquire_nowait: test 1.2 failed.\n");
		return 1;
	}
	if (spinlock_acquire_nowait(&lck))
	{
		fprintf(stderr, "spinlock_acquire_nowait: test 1.3 failed.\n");
		return 1;
	}
	spinlock_release(&lck);

	return 0;
}

static int acquire_time;

static void
test2_helper(void *data)
{
SPINLOCK   *lck = (SPINLOCK *)data;
unsigned long	t1 = time(0);

	spinlock_acquire(lck);
	acquire_time = time(0) - t1;
	spinlock_release(lck);
	return;
}

/**
 * test2	spinlock_acquire tests
 *
 * Check that spinlock correctly blocks another thread whilst the spinlock
 * is held.
 *
 * Take out a lock.
 * Start a second thread to take the same lock
 * sleep for 10 seconds
 * release lock
 * verify that second thread took at least 8 seconds to obtain the lock
 */
static int
test2()
{
SPINLOCK	lck;
void		*handle;
struct timespec sleeptime;

    sleeptime.tv_sec = 10;
    sleeptime.tv_nsec = 0;

	acquire_time = 0;
	spinlock_init(&lck);
	spinlock_acquire(&lck);
	handle = thread_start(test2_helper, (void *)&lck);
	nanosleep(&sleeptime, NULL);
	spinlock_release(&lck);
	thread_wait(handle);

	if (acquire_time < 8)
	{
		fprintf(stderr, "spinlock: test 2 failed.\n");
		return 1;
	}
	return 0;
}

/**
 * test3	spinlock_acquire tests process bound threads
 *
 * Check that spinlock correctly blocks all other threads whilst the spinlock
 * is held.
 *
 * Start multiple threads that obtain spinlock and run process bound
 */
#define THREADS 5
#define ITERATIONS 50000
#define PROCESS_LOOP 10000
#define SECONDS 15
#define NANOTIME 100000

static int  times_run, failures;
static volatile int active;
static int  threadrun[THREADS];
static int  nowait[THREADS];
static SPINLOCK lck;
static void
test3_helper(void *data)
{
// SPINLOCK   *lck = (SPINLOCK *)data;
int         i;
int         n = *(int *)data;
time_t          rawtime;

#if defined(ADD_SOME_NANOSLEEP)
struct timespec sleeptime;

    sleeptime.tv_sec = 0;
    sleeptime.tv_nsec = 1;
#endif

    while (1) {
        if (spinlock_acquire_nowait(&lck)) {
            nowait[n]++;
        }
        else {
            spinlock_acquire(&lck);
        }
        if (times_run++ > ITERATIONS) {
            break;
        }
        threadrun[n]++;
        /*
        if (99 == (times_run % 100)) {
            time ( &rawtime );
            fprintf(stderr, "%s Done %d iterations of test, in thread %d.\n", asctime (localtime ( &rawtime )), times_run, n);
        }
         */
        if (0 != active) {
            fprintf(stderr, "spinlock: test 3 failed with active non-zero after lock obtained.\n");
            failures++;
        }
        else {
            active = 1;
            for (i=0; i<PROCESS_LOOP; i++);
        }
        active = 0;
        spinlock_release(&lck);
        for (i=0; i<(4*PROCESS_LOOP); i++);
#if defined(ADD_SOME_NANOSLEEP)
        nanosleep(&sleeptime, NULL);
#endif
    }
    spinlock_release(&lck);
}

static int
test3()
{
// SPINLOCK	lck;
void		*handle[THREADS];
int             i;
int             tnum[THREADS];
time_t          rawtime;

    times_run = 0;
    active = 0;
    failures = 0;
    spinlock_init(&lck);
    time ( &rawtime );
    fprintf(stderr, "%s Starting %d threads.\n", asctime (localtime ( &rawtime )), THREADS);
    for (i = 0; i<THREADS; i++) {
        threadrun[i] = 0;
        tnum[i] = i;
        handle[i] = thread_start(test3_helper, &tnum[i]);
    }
    for (i = 0; i<THREADS; i++) {
        fprintf(stderr, "spinlock_test 3 thread %d ran %d times, no wait %d times before waits.\n", i, threadrun[i], nowait[i]);
    }
    for (i = 0; i<THREADS; i++) {
        time ( &rawtime );
        fprintf(stderr, "%s spinlock_test 3 finished sleeps, about to wait for thread %d.\n", asctime (localtime ( &rawtime )), i);
        thread_wait(handle[i]);
    }
    for (i = 0; i<THREADS; i++) {
        fprintf(stderr, "spinlock_test 3 thread %d ran %d times, no wait %d times.\n", i, threadrun[i], nowait[i]);
    }
    time ( &rawtime );
    fprintf(stderr, "%s spinlock_test 3 completed, %d failures.\n", asctime (localtime ( &rawtime )), failures);
    return 0 == failures ? 0: 1;
}

int main(int argc, char **argv)
{
int	result = 0;

	result += test1();
	result += test2();
        result += test3();

	exit(result);
}