#include <sys/resource.h>
#include <sys/time.h>
#include <stdio.h>
static double realtime0;
double sys_cputime()
{
struct rusage r;
getrusage(RUSAGE_SELF, &r);
return r.ru_utime.tv_sec + r.ru_stime.tv_sec + 1e-6 * (r.ru_utime.tv_usec + r.ru_stime.tv_usec);
}
double sys_realtime()
{
struct timeval tp;
struct timezone tzp;
gettimeofday(&tp, &tzp);
return (tp.tv_sec + tp.tv_usec * 1e-6) - realtime0;
}
void sys_liftrlimit()
{
#ifdef __linux__
struct rlimit r;
getrlimit(RLIMIT_AS, &r);
r.rlim_cur = r.rlim_max;
setrlimit(RLIMIT_AS, &r);
#endif
}
void sys_init()
{
sys_liftrlimit();
realtime0 = sys_realtime();
}
const char *sys_timestamp()
{
static char buf[256];
double rt, ct;
rt = sys_realtime();
ct = sys_cputime();
snprintf(buf, 255, "%.3f*%.2f", rt, ct/rt);
return buf;
}