// testing cancellation points

#include <errno.h>

#include <pthread.h>

#include <semaphore.h>

#include <string.h>

#include <sys/mman.h>

#include "test.h"

#define TESTC(c, m) ( (c) || (t_error(#c " failed (%s, " m ")\n", cdescr), 0) )

#define TESTR(f, m) do {int r; \

	if ((r = (f))) t_error(#f " failed: %s (%s, " m ")\n", strerror(r), cdescr); } while (0)

#define TESTE(f, m) do { \

	if ((f)==-1) t_error(#f " failed: %s (%s, " m ")\n", strerror(errno), cdescr); } while (0)

static sem_t sem_seq, sem_test;

static int seqno;

static const char *cdescr = "global initialization";

static void prepare_sem(void *arg)

{

	TESTR(sem_init(&sem_test, 0, (long)arg), "creating semaphore");

}

static void cleanup_sem(void *arg)

{

	TESTR(sem_destroy(&sem_test), "destroying semaphore");

}

static void execute_sem_wait(void *arg)

{

	TESTR(sem_wait(&sem_test), "waiting on semaphore in the canceled thread");

}

static void execute_sem_timedwait(void *arg)

{

	struct timespec ts;

	clock_gettime(CLOCK_REALTIME, &ts);

	ts.tv_sec += 1;

	TESTR(sem_timedwait(&sem_test, &ts), "timed-waiting on semaphore in the canceled thread");

}

static pthread_t td_test;

static void *run_test(void *arg)

{

	while (sem_wait(&sem_test));

	return 0;

}

static void prepare_thread(void *arg)

{

	prepare_sem(arg);

	TESTR(pthread_create(&td_test, 0, run_test, 0), "creating auxiliary thread");

}

static void cleanup_thread(void *arg)

{

	void *res;

	if (td_test) {

		TESTR(sem_post(&sem_test), "posting semaphore");

		TESTR(pthread_join(td_test, &res), "joining auxiliary thread");

		TESTC(res == 0, "auxiliary thread exit status");

	}

	cleanup_sem(arg);

}

static void execute_thread_join(void *arg)

{

	TESTR(pthread_join(td_test, 0), "joining in the canceled thread");

	td_test = 0;

}

static void prepare_dummy(void *arg)

{

}

static void execute_shm_open(void *arg)

{

	int *fd = arg;

	TESTE(*fd = shm_open("/testshm", O_RDWR|O_CREAT, 0666), "");

}

static void cleanup_shm(void *arg)

{

	int *fd = arg;

	if (*fd != -1)

		TESTE(close(*fd), "shm fd");

	TESTE(shm_unlink("/testshm"), "");

}

static struct {

	int want_cancel;

	void (*prepare)(void *);

	void (*execute)(void *);

	void (*cleanup)(void *);

	void *arg;

	const char *descr;

} scenarios[] = {

	{1, prepare_sem, execute_sem_wait, cleanup_sem, 0, "blocking sem_wait"},

	{1, prepare_sem, execute_sem_wait, cleanup_sem, (void*)1, "non-blocking sem_wait"},

	{1, prepare_sem, execute_sem_timedwait, cleanup_sem, 0, "blocking sem_timedwait"},

	{1, prepare_sem, execute_sem_timedwait, cleanup_sem, (void*)1, "non-blocking sem_timedwait"},

	{1, prepare_thread, execute_thread_join, cleanup_thread, 0, "blocking pthread_join"},

	{1, prepare_thread, execute_thread_join, cleanup_thread, (void*)1, "non-blocking pthread_join"},

	{0, prepare_dummy, execute_shm_open, cleanup_shm, &(int){0}, "shm_open"},

	{ 0 }

}, *cur_sc = scenarios;

static void *run_execute(void *arg)

{

	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, 0);

	while (sem_wait(&sem_seq));

	pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, 0);

	seqno = 1;

	cur_sc->execute(cur_sc->arg);

	seqno = 2;

	return 0;

}

int main(void)

{

	TESTR(sem_init(&sem_seq, 0, 0), "creating semaphore");

	for (; cur_sc->prepare; cur_sc++) {

		pthread_t td;

		void *res;

		cdescr = cur_sc->descr;

		cur_sc->prepare(cur_sc->arg);

		seqno = 0;

		TESTR(pthread_create(&td, 0, run_execute, 0), "creating thread to be canceled");

		TESTR(pthread_cancel(td), "canceling");

		TESTR(sem_post(&sem_seq), "unblocking canceled thread");

		TESTR(pthread_join(td, &res), "joining canceled thread");

		if (cur_sc->want_cancel) {

			TESTC(res == PTHREAD_CANCELED, "canceled thread exit status")

			&& TESTC(seqno == 1, "seqno");

		} else {

			TESTC(res != PTHREAD_CANCELED, "canceled thread exit status")

			&& TESTC(seqno == 2, "seqno");

		}

		cur_sc->cleanup(cur_sc->arg);

	}

	return t_status;

}