1#include <limits.h>
2#include <time.h>
3
4#include "threads_impl.h"
5
6clock_t clock(void) {
7    struct timespec ts;
8
9    if (__clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts))
10        return -1;
11
12    if (ts.tv_sec > LONG_MAX / 1000000 || ts.tv_nsec / 1000 > LONG_MAX - 1000000 * ts.tv_sec)
13        return -1;
14
15    return ts.tv_sec * 1000000 + ts.tv_nsec / 1000;
16}
17