#include	<unistd.h>
#include	<sys/time.h>
#include	<sys/times.h>
#include	<sys/resource.h>

/* The same code is used for both C and Fortran entry points.
 */
#define	WC_GUTS								\
									\
  struct timeval s_val;							\
									\
  gettimeofday(&s_val,0);						\
  return ((double) s_val.tv_sec + 0.000001*s_val.tv_usec);

/* Returns the current value of the wall clock timer.
 * C entry point.
 */
double
wc_second()

{
  WC_GUTS;
}

/* Returns the current value of the wall clock timer.
 * Fortran entry point.
 */
double
wc_second_()

{
  WC_GUTS;
}

#define	US_GUTS								\
									\
  struct	rusage	ru;						\
  double	tu, ts;							\
									\
  getrusage(RUSAGE_SELF,&ru);						\
									\
  tu = ru.ru_utime.tv_sec + 1.0e-6*ru.ru_utime.tv_usec;			\
  ts = ru.ru_stime.tv_sec + 1.0e-6*ru.ru_stime.tv_usec;			\
									\
  return (tu + ts);							\

/* Returns the current value of the user+system timer.  C entry point.
 */
double
us_second()

{
  US_GUTS;
}

/* Returns the current value of the user+system timer.  Fortran entry point.
 */
double
us_second_()

{
  US_GUTS;
}

#include <sys/types.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/syssgi.h>
#include <sys/immu.h>
#include <stdio.h>

#define	TICKUNITS	(1.0e-12)
#define	TRUE		(1)
#define	FALSE		(0)
#define	IO4_TIMER_IS_64BIT	(TRUE)

#if IO4_TIMER_IS_64BIT
typedef unsigned long	long iotimer_t;
#else
typedef unsigned int	iotimer_t;
#endif

#define	RT_GUTS								\
									\
  static int			first = TRUE;				\
  static volatile iotimer_t	*iotimer_addr, counter_value0;		\
  static double			tick;					\
  unsigned int			cycleval;				\
  volatile iotimer_t		counter_value;				\
									\
  if (first) {								\
									\
    __psunsigned_t	phys_addr, raddr, poffmask;			\
    int			fd;						\
									\
    poffmask       = getpagesize() - 1;					\
    phys_addr      = syssgi(SGI_QUERY_CYCLECNTR, &cycleval);		\
    raddr          = phys_addr & ~poffmask;				\
    fd             = open("/dev/mmem", O_RDONLY);			\
    iotimer_addr   = (volatile iotimer_t *) mmap(NULL, poffmask,	\
                                                 PROT_READ,		\
                                                 MAP_PRIVATE, fd,	\
                                                 (__psint_t) raddr);	\
    iotimer_addr   = (iotimer_t *) ((__psunsigned_t) iotimer_addr +	\
                                    (phys_addr & poffmask));		\
    tick           = cycleval * TICKUNITS;				\
    counter_value0 = *iotimer_addr;					\
    first          = FALSE;						\
    return (0.0);							\
  }									\
									\
  counter_value = *iotimer_addr;					\
									\
  return ((counter_value - counter_value0) * tick);


/* Gets the time from the free running hardware counter.  The time
 * is accurate until the counter wraps around, but no warning about
 * wrap around is provided.  C entry point.
 */
double
rt_second()

{
  RT_GUTS;
}

/* Gets the time from the free running hardware counter.  The time
 * is accurate until the counter wraps around, but no warning about
 * wrap around is provided.  Fortran entry point.
 */
double
rt_second_()

{
  RT_GUTS;
}

/* Returns the current value of the real-time timer, wall clock timer, or
 * user+system timer depending on the valueof tmode: 0 means the real-time
 * timer, less than zero the wall-clock timer, and greater than zero
 * user+system time.  C entry point.
 */
double
second(

int	tmode)

{
  if (tmode == 0) {
    RT_GUTS;
  } else if (tmode > 0) {
    US_GUTS;
  } else {
    WC_GUTS;
  }
}

/* Returns the current value of the real-time timer, wall clock timer, or
 * user+system timer depending on the valueof tmode: 0 means the real-time
 * timer, less than zero the wall-clock timer, and greater than zero
 * user+system time.  C entry point.
 */
double
second_(

int	*ptmode)

{
  int	tmode = *ptmode;

  if (tmode == 0) {
    RT_GUTS;
  } else if (tmode > 0) {
    US_GUTS;
  } else {
    WC_GUTS;
  }
}