#include <pthread.h>
#include <stdio.h>
#include <assert.h>
#include <errno.h>

void *
thr_routine(void *arg)
{
	pthread_mutex_t *m = (pthread_mutex_t *)arg;
	int err;

	printf("thread %p: locking mutex...\n", pthread_self());
	err = pthread_mutex_lock(m);
	if (err == EOWNERDEAD) {
		printf("thread %p: found owner is dead, try to fix it.\n",
			pthread_self());
		int ret = pthread_mutex_consistent(m);
		printf("thread %p: pthread_mutex_consistent returns %d.\n",
			pthread_self(), ret);
		assert(pthread_mutex_unlock(m) == 0);
		printf("thread %p: unlocked mutex.\n", pthread_self());
		printf("thread %p: trying to relock it.\n", pthread_self());
		err = pthread_mutex_lock(m);
		if (err == 0) {
			printf("thread %p: relock success.\n", pthread_self());
			assert(pthread_mutex_unlock(m) == 0);
		} else {
			pthread_mutex_unlock(m);
		}
	} else if (err == ENOTRECOVERABLE) {
		printf("thread %p: found owner is dead.\n", pthread_self());
	} else {
		printf("thread %p: unknown error %d.\n", pthread_self(), err);
	}
}

int
test1(void)
{
	pthread_t td;
	pthread_mutex_t m;
	pthread_mutexattr_t ma;
	int ret;

	pthread_mutexattr_init(&ma);
	assert(pthread_mutexattr_setrobust(&ma, PTHREAD_MUTEX_ROBUST) == 0);
	assert(pthread_mutex_init(&m, &ma) == 0);
	pthread_mutexattr_destroy(&ma);

	assert(pthread_mutex_lock(&m) == 0);
	printf("thread %p: locked mutex.\n", pthread_self());
	assert(pthread_create(&td, NULL, thr_routine, &m) == 0);
	sleep(1);
	printf("thread %p: exits without unlocking mutex.\n", pthread_self());
	pthread_exit(0);
}

int
main()
{
	test1();
}