Ruby

def test_clock_gettime

begin

t1 = Process.clock_gettime(Process::CLOCK_REALTIME)

rescue NotImplementedError

return

end

t2 = Time.now

t2 = t2.tv_sec * 1000000000 + t2.tv_nsec

assert_operator(t1, :<=, t2)

t1 = Time.now

t1 = t1.tv_sec * 1000000000 + t1.tv_nsec

t2 = Process.clock_gettime(Process::CLOCK_REALTIME)

assert_operator(t1, :<=, t2)

end

#if defined(HAVE_CLOCK_GETTIME)

/*

* call-seq:

* Process.clock_gettime(clk_id) -> integer

*

* Returns a number of nanoseconds returned by POSIX clock_gettime() function.

*

* _clk_id_ specifies a kind of clock.

* It is specifed as a constant which begins with <code>Process::CLOCK_</code>

* such like <code>Process::CLOCK_REALTIME</code> and

* <code>Process::CLOCK_MONOTONIC</code>.

* The supported constants depends on OS and version.

* Ruby provides following type of _clk_id_ if available.

*

* [CLOCK_REALTIME] POSIX, Linux, FreeBSD, NetBSD

* [CLOCK_MONOTONIC] POSIX, Linux, FreeBSD, NetBSD

* [CLOCK_PROCESS_CPUTIME_ID] POSIX, Linux

* [CLOCK_THREAD_CPUTIME_ID] POSIX, Linux

*

* The origin (zero) of the returned value, number of nanoseconds,

* varies.

* For example, system start up time, process start up time, the Epoch, etc.

*

* The origin in CLOCK_REALTIME is defined as the Epoch

* (1970-01-01 00:00:00 UTC).

* But some systems count leap seconds and others doesn't.

* So the number of nanoseconds can be interpreted differently across systems.

*

* p Process.clock_gettime(Process::CLOCK_MONOTONIC)

* #=> 2684827897652283

*

*/

VALUE

rb_clock_gettime(VALUE obj, VALUE clk_id)

{

clockid_t c;

struct timespec ts;

int ret;

c = NUM2CLOCKID(clk_id);

ret = clock_gettime(c, &ts);

if (ret == -1)

rb_sys_fail(0);

#if defined(HAVE_LONG_LONG)

if (!MUL_OVERFLOW_SIGNED_INTEGER_P(1000000000, (LONG_LONG)ts.tv_sec,

LLONG_MIN, LLONG_MAX-999999999)) {

return LL2NUM(ts.tv_nsec + 1000000000 * (LONG_LONG)ts.tv_sec);

}

#endif

return rb_funcall(LONG2FIX(ts.tv_nsec), '+', 1,

rb_funcall(LONG2FIX(1000000000), '*', 1, TIMET2NUM(ts.tv_sec)));

}

#else

#define rb_clock_gettime rb_f_notimplement

#endif

#ifdef CLOCK_REALTIME

rb_define_const(rb_mProcess, "CLOCK_REALTIME", CLOCKID2NUM(CLOCK_REALTIME));

#endif

#ifdef CLOCK_MONOTONIC

rb_define_const(rb_mProcess, "CLOCK_MONOTONIC", CLOCKID2NUM(CLOCK_MONOTONIC));

#endif

#ifdef CLOCK_PROCESS_CPUTIME_ID

rb_define_const(rb_mProcess, "CLOCK_PROCESS_CPUTIME_ID", CLOCKID2NUM(CLOCK_PROCESS_CPUTIME_ID));

#endif

#ifdef CLOCK_THREAD_CPUTIME_ID

rb_define_const(rb_mProcess, "CLOCK_THREAD_CPUTIME_ID", CLOCKID2NUM(CLOCK_THREAD_CPUTIME_ID));

#endif

rb_define_module_function(rb_mProcess, "clock_gettime", rb_clock_gettime, 1);

RUBY_REPLACE_TYPE(clockid_t, [], CLOCKID)