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| | /*
* this header includes functions to support broken systems
* without clock_gettime() or CLOCK_MONOTONIC
*/
#ifndef HAVE_TYPE_CLOCKID_T
typedef int clockid_t;
#endif
#ifndef HAVE_CLOCK_GETTIME
# ifndef CLOCK_REALTIME
# define CLOCK_REALTIME 0 /* whatever */
# endif
static int fake_clock_gettime(clockid_t clk_id, struct timespec *res)
{
struct timeval tv;
int r = gettimeofday(&tv, NULL);
assert(0 == r && "gettimeofday() broke!?");
res->tv_sec = tv.tv_sec;
res->tv_nsec = tv.tv_usec * 1000;
return r;
}
# define clock_gettime fake_clock_gettime
#endif /* broken systems w/o clock_gettime() */
/*
* UGH
* CLOCK_MONOTONIC is not guaranteed to be a macro, either
*/
#ifndef CLOCK_MONOTONIC
# if (!defined(_POSIX_MONOTONIC_CLOCK) || !defined(HAVE_CLOCK_MONOTONIC))
# define CLOCK_MONOTONIC CLOCK_REALTIME
# endif
#endif
/*
* Availability of a monotonic clock needs to be detected at runtime
* since we could've been built on a different system than we're run
* under.
*/
static clockid_t hopefully_CLOCK_MONOTONIC;
static int check_clock(void)
{
struct timespec now;
hopefully_CLOCK_MONOTONIC = CLOCK_MONOTONIC;
/* we can't check this reliably at compile time */
if (clock_gettime(CLOCK_MONOTONIC, &now) == 0)
return 1;
if (clock_gettime(CLOCK_REALTIME, &now) == 0) {
hopefully_CLOCK_MONOTONIC = CLOCK_REALTIME;
rb_warn("CLOCK_MONOTONIC not available, "
"falling back to CLOCK_REALTIME");
return 2;
}
return -1;
}
|