cpu_time.c

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/* LINTLIBRARY */

#include <stdio.h>
#include "CUDD/util.h"

#ifdef IBM_WATC     /* IBM Waterloo-C compiler (same as bsd 4.2) */
#define void int
#define BSD
#endif

#ifdef BSD
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#endif

#if defined(UNIX60) || defined(UNIX100) || defined(__CYGWIN32__)
#include <sys/types.h>
#include <sys/times.h>
#endif

#ifdef vms      /* VAX/C compiler -- times() with 100 HZ clock */
#include <types.h>
#include <time.h>
#endif



/*
 *   util_cpu_time -- return a long which represents the elapsed processor
 *   time in milliseconds since some constant reference
 */
long 
util_cpu_time()
{
    long t = 0;

#ifdef BSD
    struct rusage rusage;
    (void) getrusage(RUSAGE_SELF, &rusage);
    t = (long) rusage.ru_utime.tv_sec*1000 + rusage.ru_utime.tv_usec/1000;
#endif

#ifdef IBMPC
    long ltime;
    (void) time(&ltime);
    t = ltime * 1000;
#endif

#ifdef UNIX60           /* times() with 60 Hz resolution */
    struct tms buffer;
    times(&buffer);
    t = buffer.tms_utime * 16.6667;
#endif

#ifdef UNIX100
    struct tms buffer;      /* times() with 100 Hz resolution */
    times(&buffer);
    t = buffer.tms_utime * 10;
#endif

#ifdef __CYGWIN32__
    /* Works under Windows NT but not Windows 95. */
    struct tms buffer;      /* times() with 1000 Hz resolution */
    times(&buffer);
    t = buffer.tms_utime;
#endif

#ifdef vms
    tbuffer_t buffer;   /* times() with 100 Hz resolution */
    times(&buffer);
    t = buffer.proc_user_time * 10;
#endif

    return t;
}