C++ clock_get_time函数代码示例

void process_execute(void)
{
  // Find first non-empty queue
  int qi = 0;
  while (qi < NB_PROCESS_EVENT_PRIORITIES && queues[qi].count == 0) {
    qi += 1;
  }
  if (qi == NB_PROCESS_EVENT_PRIORITIES) {
    // No events to process
    return;
  }

  // Process one event from the selected queue
  struct event e;
  struct event_queue* q = &queues[qi];
  ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
    e = q->queue[q->first];
    q->count -= 1;
    q->first = (q->first + 1) % PROCESS_CONF_EVENT_QUEUE_SIZE;
  }
#ifdef PROCESS_STATS
  clock_time_t clock_before = clock_get_time();
#endif
  e.p->thread(e.p, e.ev, e.data);
#ifdef PROCESS_STATS
  clock_time_t duration = clock_get_time() - clock_before;
  e.p->time += duration;
#endif
}

/* Refresh rate calculation */
static void nvstusb_print_refresh_rate(void)
{
  static int i_it = 0;
  static uint64_t i_last = 0;
  static uint64_t i_first = 0;
  static uint64_t i_acc_var = 0;
  double f_mean, f_var;

  /* First frame */
  if(i_it == 0) {
    struct timespec s_tmp;

#ifdef __MACH__
    clock_serv_t cclock;
    mach_timespec_t mts;
    host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
    clock_get_time(cclock, &mts);
    mach_port_deallocate(mach_task_self(), cclock);
    s_tmp.tv_sec = mts.tv_sec;
    s_tmp.tv_nsec = mts.tv_nsec;
#else
    clock_gettime(CLOCK_REALTIME, &s_tmp);
#endif
    i_first = (uint64_t)s_tmp.tv_sec*1000000+(uint64_t)s_tmp.tv_nsec/1000;
    i_last = i_first;
    f_mean = 0;
    f_var = 0;

  } else {
    struct timespec s_tmp;
#ifdef __MACH__
    clock_serv_t cclock;
    mach_timespec_t mts;
    host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
    clock_get_time(cclock, &mts);
    mach_port_deallocate(mach_task_self(), cclock);
    s_tmp.tv_sec = mts.tv_sec;
    s_tmp.tv_nsec = mts.tv_nsec;
#else
    clock_gettime(CLOCK_REALTIME, &s_tmp);
#endif
    uint64_t i_new = (uint64_t)s_tmp.tv_sec*1000000+(uint64_t)s_tmp.tv_nsec/1000;
    /* Update average */
    f_mean = (double)(i_new-i_first)/(i_it);
    /* Calculate variance */
    i_acc_var += pow((double)(i_new-i_last)-f_mean, 2);

    /* std dev */
    f_var = (double)sqrt(i_acc_var/i_it);
    i_last = i_new;

    /* Display each 512 frame */
    if(i_it % 512 == 0) {
      fprintf(stderr,"nvstusb: frame:%d (%0.2f s) mean: %f Hz (%0.2f us) sqrt(var): %0.2f us (%0.1f %%)\n",i_it,f_mean*i_it/1000000.0, 1000000/f_mean, f_mean, f_var, 100.0*f_var/f_mean);
    }
  }
  /* Increment frame counter */
  i_it++;
}

int
nanosleep(const struct timespec *requested_time, struct timespec *remaining_time) {
    kern_return_t kret;
    int ret;
    mach_timespec_t current;
    mach_timespec_t completion;
   
	if (__unix_conforming == 0)
		__unix_conforming = 1;

#ifdef VARIANT_CANCELABLE
    pthread_testcancel();
#endif /* VARIANT_CANCELABLE */

    if ((requested_time == NULL) || (requested_time->tv_sec < 0) || (requested_time->tv_nsec >= NSEC_PER_SEC)) {
        errno = EINVAL;
        return -1;
    }


    if (remaining_time != NULL) {
	/* once we add requested_time, this will be the completion time */
        kret = clock_get_time(clock_port, &completion);
        if (kret != KERN_SUCCESS) {
            fprintf(stderr, "clock_get_time() failed: %s\n", mach_error_string(kret));
            errno = EINVAL;
            return -1;
        }
    }
    ret = SEMWAIT_SIGNAL(clock_sem, MACH_PORT_NULL, 1, 1, (int64_t)requested_time->tv_sec, (int32_t)requested_time->tv_nsec);    
    if (ret < 0) {
        if (errno == ETIMEDOUT) {
		return 0;
        } else if (errno == EINTR) {
            if (remaining_time != NULL) {
                ret = clock_get_time(clock_port, &current);
                if (ret != KERN_SUCCESS) {
                    fprintf(stderr, "clock_get_time() failed: %s\n", mach_error_string(ret));
                    return -1;
                }
                /* This depends on the layout of a mach_timespec_t and timespec_t being equivalent */
                ADD_MACH_TIMESPEC(&completion, requested_time);
		/* We have to compare first, since mach_timespect_t contains unsigned integers */
		if(CMP_MACH_TIMESPEC(&completion, &current) > 0) {
		    SUB_MACH_TIMESPEC(&completion, &current);
		    remaining_time->tv_sec = completion.tv_sec;
		    remaining_time->tv_nsec = completion.tv_nsec;
		} else {
		    bzero(remaining_time, sizeof(*remaining_time));
		}
            }
        } else {
            errno = EINVAL;
	}
    }
    return -1;
}

void smaccm_thread_calendar() {
	if ((smaccm_calendar_counter % (100 / smaccm_tick_interval)) == 0) {
		// MWW: modification of time type to match Ivory/Tower (CAmkES time server uses uint64_t)
		int64_t the_time = (int64_t)clock_get_time();
		PixhawkProxy_periodic_dispatcher_write_int64_t(&the_time); 
	}if ((smaccm_calendar_counter % (100 / smaccm_tick_interval)) == 0) {
		// MWW: modification of time type to match Ivory/Tower (CAmkES time server uses uint64_t)
		int64_t the_time = (int64_t)clock_get_time();
		Input_periodic_dispatcher_write_int64_t(&the_time); 
	}

	smaccm_calendar_counter = (smaccm_calendar_counter + 1) % smaccm_hyperperiod_subdivisions; 
	smaccm_calendar_ticks++; 
}

void wTimeNow(wTime* time)
{
    #if defined(__APPLE__)

    // Mac OS does not have clock_gettime, use clock_get_time
    // Another option is to use gettimeofday() for both Linux and Mac
    // but it's deprecated and not recommended due to not being monotonic

    mach_timespec_t mts;
    int ret = clock_get_time(gClockServ, &mts);
    assert(ret == 0);

    time->tv_sec  = mts.tv_sec;
    time->tv_nsec = mts.tv_nsec;

    #elif defined(__linux__)

    int ret = clock_gettime(CLOCK_REALTIME, time);
    assert(ret == 0);

    #elif defined(__WIN32__)

    int ret = QueryPerformanceCounter(time);
    assert(ret != 0);

    #endif
}

/*
 *  Synopsis:
 *	Emulate Posix clock_gettime() using Mach system routines.
 */
int clock_gettime(clockid_t id, struct timespec *tp)
{
	clock_serv_t service_id;
	clock_id_t mach_id;
	mach_timespec_t now;
	kern_return_t status;

	switch (id) {
	case CLOCK_REALTIME:
		mach_id = CALENDAR_CLOCK;
		break;
	case CLOCK_MONOTONIC:
		mach_id = SYSTEM_CLOCK;
		break;
	default:
		errno = EINVAL;
		return -1;
	}
	status = host_get_clock_service(mach_host_self(), mach_id, &service_id);
	if (status != KERN_SUCCESS) {
		errno = EINVAL;
		return -1;
	}
	status = clock_get_time(service_id, &now);
	if (status != KERN_SUCCESS) {
		errno = EINVAL;
		return -1;
	}
	tp->tv_sec  = now.tv_sec;
	tp->tv_nsec = now.tv_nsec;
	return 0;
}

double bsp_time() {

	//get init data
	const struct mcbsp_thread_data * const data = mcbsp_internal_const_prefunction();

	//get stop time

#ifdef __MACH__
	//get rights for accessing Mach's timers
	const kern_return_t rc1 = host_get_clock_service( mach_host_self(), SYSTEM_CLOCK, &(data->clock) );
	if( rc1 != KERN_SUCCESS ) {
		fprintf( stderr, "Could not access the Mach system timer (%s)\n", mach_error_string( rc1 ) );
		mcbsp_util_fatal();
	}

	mach_timespec_t stop;
	const kern_return_t rc2 = clock_get_time( data->clock, &stop );
	if( rc2 != KERN_SUCCESS ) {
		fprintf( stderr, "Could not get time at call to bsp_time (%s)\n", mach_error_string( rc2 ) );
		mcbsp_util_fatal();
	}
#else
	struct timespec stop;
	clock_gettime( CLOCK_MONOTONIC, &stop);
#endif

	//return time
	double time = (stop.tv_sec-data->start.tv_sec);
	time += (stop.tv_nsec-data->start.tv_nsec)/1000000000.0;
	return time;
}

/* return current monotonic time in milliseconds (ms). */
uint64_t current_time_monotonic(void)
{
    uint64_t time;
#if defined(_WIN32) || defined(__WIN32__) || defined (WIN32)
    time = (uint64_t)GetTickCount() + add_monotime;

    if (time < last_monotime) { /* Prevent time from ever decreasing because of 32 bit wrap. */
        uint32_t add = ~0;
        add_monotime += add;
        time += add;
    }

    last_monotime = time;
#else
    struct timespec monotime;
#if defined(__linux__) && defined(CLOCK_MONOTONIC_RAW)
    clock_gettime(CLOCK_MONOTONIC_RAW, &monotime);
#elif defined(__APPLE__)
    clock_serv_t muhclock;
    mach_timespec_t machtime;

    host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &muhclock);
    clock_get_time(muhclock, &machtime);
    mach_port_deallocate(mach_task_self(), muhclock);

    monotime.tv_sec = machtime.tv_sec;
    monotime.tv_nsec = machtime.tv_nsec;
#else
    clock_gettime(CLOCK_MONOTONIC, &monotime);
#endif
    time = 1000ULL * monotime.tv_sec + (monotime.tv_nsec / 1000000ULL);
#endif
    return time;
}

  /*
  std::string timestamp::to_string( bool local ) const {
    return ctime_adapter(*this).strftime( "%Y-%m-%d, %H:%M:%S" , local);
  }
  */
  timestamp timestamp::now( void ) {
#if defined( __codex_win32__ )
    FILETIME ft;
    GetSystemTimeAsFileTime( &ft );
    LARGE_INTEGER qp;
    qp.HighPart = ft.dwHighDateTime;
    qp.LowPart = ft.dwLowDateTime;
    int64_t value = qp.QuadPart / 10;
    static const int64_t TICK_OFFSET = -11644473600 * 1000 * 1000;
    value += TICK_OFFSET;
    return timestamp(value);
#elif defined( __codex_linux__ )
    struct timespec ts;
    int64_t value= 0;
    if( clock_gettime( CLOCK_REALTIME , &ts ) == -1 ) {
      value = std::time(nullptr) * 1000 * 1000;
    } else {
      value = ( ts.tv_sec * 1000 * 1000 ) + (ts.tv_nsec / 1000);
    }
    return timestamp(value);    
#elif defined( __codex_apple__ )
    struct timespec ts;
    int64_t value = 0;
    clock_serv_t cclock;
    mach_timespec_t mts;
    host_get_clock_service(mach_host_self() , CALENDAR_CLOCK , &cclock );
    clock_get_time( cclock , &mts );
    mach_port_deallocate(mach_task_self() , cclock );
    ts.tv_sec = mts.tv_sec;
    ts.tv_nsec = mts.tv_nsec;
    value = ( ts.tv_sec * 1000 * 1000 ) + (ts.tv_nsec / 1000);
    return timestamp(value);
#endif
  }

bool scond_wait_timeout(scond_t *cond, slock_t *lock, unsigned timeout_ms)
{
   struct timespec now;

#ifdef __MACH__ // OSX doesn't have clock_gettime ... :(
   clock_serv_t cclock;
   mach_timespec_t mts;
   host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
   clock_get_time(cclock, &mts);
   mach_port_deallocate(mach_task_self(), cclock);
   now.tv_sec = mts.tv_sec;
   now.tv_nsec = mts.tv_nsec;
#else
   clock_gettime(CLOCK_REALTIME, &now);
#endif

   now.tv_sec += timeout_ms / 1000;
   now.tv_nsec += timeout_ms * 1000000L;

   now.tv_sec += now.tv_nsec / 1000000000L;
   now.tv_nsec = now.tv_nsec % 1000000000L;

   int ret = pthread_cond_timedwait(&cond->cond, &lock->lock, &now);
   return ret == 0;
}

unsigned long hwtimer_arch_now(void)
{
    struct timespec t;

    DEBUG("hwtimer_arch_now()\n");

    _native_syscall_enter();
#ifdef __MACH__
    clock_serv_t cclock;
    mach_timespec_t mts;
    host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &cclock);
    clock_get_time(cclock, &mts);
    mach_port_deallocate(mach_task_self(), cclock);
    t.tv_sec = mts.tv_sec;
    t.tv_nsec = mts.tv_nsec;
#else

    if (real_clock_gettime(CLOCK_MONOTONIC, &t) == -1) {
        err(EXIT_FAILURE, "hwtimer_arch_now: clock_gettime");
    }

#endif
    _native_syscall_leave();

    native_hwtimer_now = ts2ticks(&t) - time_null;

    struct timeval tv;
    ticks2tv(native_hwtimer_now, &tv);
    DEBUG("hwtimer_arch_now(): it is now %lu s %lu us\n",
            (unsigned long)tv.tv_sec, (unsigned long)tv.tv_usec);
    DEBUG("hwtimer_arch_now(): returning %lu\n", native_hwtimer_now);
    return native_hwtimer_now;
}

bool cResetEvent::Wait(unsigned msec)//Wait for signal , then reset
{
	pthread_mutex_lock( &mutx );
	if (!state)
	{
		struct timespec ts;
		#if HOST_OS == OS_DARWIN
			// OSX doesn't have clock_gettime.
			clock_serv_t cclock;
			mach_timespec_t mts;

			host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
			clock_get_time(cclock, &mts);
			mach_port_deallocate(mach_task_self(), cclock);
			ts.tv_sec = mts.tv_sec;
			ts.tv_nsec = mts.tv_nsec;
		#else
			clock_gettime(CLOCK_REALTIME, &ts);
		#endif
		ts.tv_sec += msec / 1000;
		ts.tv_nsec += (msec % 1000) * 1000000;
		while (ts.tv_nsec > 1000000000)
		{
			ts.tv_nsec -= 1000000000;
			ts.tv_sec++;
		}
		pthread_cond_timedwait( &cond, &mutx, &ts );
	}
	bool rc = state;
	state=false;
	pthread_mutex_unlock( &mutx );

	return rc;
}

unsigned long hwtimer_arch_now(void)
{
    struct timespec t;

    DEBUG("hwtimer_arch_now()\n");

    _native_in_syscall = 1;
#ifdef __MACH__
    clock_serv_t cclock;
    mach_timespec_t mts;
    host_get_clock_service(mach_host_self(), SYSTEM_CLOCK, &cclock);
    clock_get_time(cclock, &mts);
    mach_port_deallocate(mach_task_self(), cclock);
    t.tv_sec = mts.tv_sec;
    t.tv_nsec = mts.tv_nsec;
#else

    if (clock_gettime(CLOCK_MONOTONIC, &t) == -1) {
        err(1, "hwtimer_arch_now: clock_gettime");
    }

#endif
    _native_in_syscall = 0;

    native_hwtimer_now = ts2ticks(&t) - time_null;

    DEBUG("hwtimer_arch_now(): it is now %lu s %lu ns\n",
            (unsigned long)t.tv_sec, (unsigned long)t.tv_nsec);
    DEBUG("hwtimer_arch_now(): returning %lu\n", native_hwtimer_now);
    return native_hwtimer_now;
}

void
osfmach3_get_time(
	struct timeval *xtime)
{
	tvalspec_t	cur_time;

#ifdef	__powerpc__
	if (use_highres && MACH_PORT_VALID(rt_clock)) {
		kern_return_t	kr;

		/*
		 * We want a higher resolution time: ask the microkernel.
		 * XXX this doesn't work on MP PowerMac systems.
		 */
		kr = clock_get_time(rt_clock, &cur_time);
		if (kr != KERN_SUCCESS) {
			MACH3_DEBUG(2, kr,
				    ("osfmach3_get_time: clock_get_time(0x%x)",
				     rt_clock));
			/* use mapped time */
			MTS_TO_TS(serv_mtime, &cur_time);
		}
	} else {
		MTS_TO_TS(serv_mtime, &cur_time);
	}
#else	/* __powerpc__ */
	MTS_TO_TS(serv_mtime, &cur_time);
#endif	/* __powerpc__ */
	xtime->tv_sec = cur_time.tv_sec + base_time.tv_sec;
	xtime->tv_usec = (cur_time.tv_nsec + base_time.tv_nsec) / 1000;
	if (xtime->tv_usec >= USEC_PER_SEC) {
		xtime->tv_sec++;
		xtime->tv_usec -= USEC_PER_SEC;
	}
}

/** @This allocates a new uclock structure.
 *
 * @param flags flags for the creation of a uclock structure
 * @return pointer to uclock, or NULL in case of error
 */
struct uclock *uclock_std_alloc(enum uclock_std_flags flags)
{
#ifdef __MACH__
    clock_serv_t cclock;
    mach_timespec_t ts;
    if (unlikely(host_get_clock_service(mach_host_self(), unlikely(flags & UCLOCK_FLAG_REALTIME) ? CALENDAR_CLOCK : REALTIME_CLOCK, &cclock) < 0)) {
        return NULL;
    }
    if(unlikely(clock_get_time(cclock, &ts) < 0)) {
        mach_port_deallocate(mach_task_self(), cclock);
        return NULL;
    }
#else
    struct timespec ts;
    if (unlikely(clock_gettime(unlikely(flags & UCLOCK_FLAG_REALTIME) ?
                               CLOCK_REALTIME : CLOCK_MONOTONIC, &ts) == -1))
        return NULL;
#endif

    struct uclock_std *uclock_std = malloc(sizeof(struct uclock_std));
    if (unlikely(uclock_std == NULL))
        return NULL;
    uclock_std->flags = flags;
    urefcount_init(uclock_std_to_urefcount(uclock_std), uclock_std_free);
    uclock_std->uclock.refcount = uclock_std_to_urefcount(uclock_std);
    uclock_std->uclock.uclock_now = uclock_std_now;
    uclock_std->uclock.uclock_to_real = uclock_std_to_real;
    uclock_std->uclock.uclock_from_real = uclock_std_from_real;
#ifdef __MACH__
    memcpy(&uclock_std->cclock, &cclock, sizeof(cclock));
#endif
    return uclock_std_to_uclock(uclock_std);
}