#include <errno.h>
#include <stdatomic.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <mach/mach_error.h>
#include <mach/mach_time.h>
#include <os/base_private.h>
extern uint64_t __thread_selfusage(void);
#define timeval2nsec(tv) (tv.tv_sec * NSEC_PER_SEC + tv.tv_usec * NSEC_PER_USEC)
static uint64_t
_boottime_fallback_usec(void)
{
struct timeval tv;
size_t len = sizeof(tv);
int ret = sysctlbyname("kern.boottime", &tv, &len, NULL, 0);
if (ret == -1) return 0;
return (uint64_t)tv.tv_sec * USEC_PER_SEC + (uint64_t)tv.tv_usec;
}
static int
_mach_boottime_usec(uint64_t *boottime, struct timeval *realtime)
{
uint64_t bt1 = 0, bt2 = 0;
int ret;
do {
bt1 = mach_boottime_usec();
if (os_slowpath(bt1 == 0)) bt1 = _boottime_fallback_usec();
atomic_thread_fence(memory_order_seq_cst);
ret = gettimeofday(realtime, NULL);
if (ret != 0) return ret;
atomic_thread_fence(memory_order_seq_cst);
bt2 = mach_boottime_usec();
if (os_slowpath(bt2 == 0)) bt2 = _boottime_fallback_usec();
} while (os_slowpath(bt1 != bt2));
*boottime = bt1;
return 0;
}
uint64_t
clock_gettime_nsec_np(clockid_t clock_id)
{
switch(clock_id){
case CLOCK_REALTIME: {
struct timeval tv;
int ret = gettimeofday(&tv, NULL);
if (ret) return 0;
return timeval2nsec(tv);
}
case CLOCK_MONOTONIC: {
struct timeval tv;
uint64_t boottime;
int ret = _mach_boottime_usec(&boottime, &tv);
if (ret) return 0;
boottime *= NSEC_PER_USEC;
return timeval2nsec(tv) - boottime;
}
case CLOCK_PROCESS_CPUTIME_ID: {
struct rusage ru;
int ret = getrusage(RUSAGE_SELF, &ru);
if (ret) return 0;
return timeval2nsec(ru.ru_utime) + timeval2nsec(ru.ru_stime);
}
default:
break;
}
mach_timebase_info_data_t tb_info;
if (mach_timebase_info(&tb_info)) return 0;
uint64_t mach_time;
switch(clock_id){
case CLOCK_MONOTONIC_RAW:
mach_time = mach_continuous_time();
break;
case CLOCK_MONOTONIC_RAW_APPROX:
mach_time = mach_continuous_approximate_time();
break;
case CLOCK_UPTIME_RAW:
mach_time = mach_absolute_time();
break;
case CLOCK_UPTIME_RAW_APPROX:
mach_time = mach_approximate_time();
break;
case CLOCK_THREAD_CPUTIME_ID:
mach_time = __thread_selfusage();
break;
default:
errno = EINVAL;
return 0;
}
return (mach_time * tb_info.numer) / tb_info.denom;
}
int
clock_gettime(clockid_t clk_id, struct timespec *tp)
{
switch(clk_id){
case CLOCK_REALTIME: {
struct timeval tv;
int ret = gettimeofday(&tv, NULL);
TIMEVAL_TO_TIMESPEC(&tv, tp);
return ret;
}
case CLOCK_MONOTONIC: {
struct timeval tv;
uint64_t boottime_usec;
int ret = _mach_boottime_usec(&boottime_usec, &tv);
struct timeval boottime = {
.tv_sec = boottime_usec / USEC_PER_SEC,
.tv_usec = boottime_usec % USEC_PER_SEC
};
timersub(&tv, &boottime, &tv);
TIMEVAL_TO_TIMESPEC(&tv, tp);
return ret;
}
case CLOCK_PROCESS_CPUTIME_ID: {
struct rusage ru;
int ret = getrusage(RUSAGE_SELF, &ru);
timeradd(&ru.ru_utime, &ru.ru_stime, &ru.ru_utime);
TIMEVAL_TO_TIMESPEC(&ru.ru_utime, tp);
return ret;
}
case CLOCK_MONOTONIC_RAW:
case CLOCK_MONOTONIC_RAW_APPROX:
case CLOCK_UPTIME_RAW:
case CLOCK_UPTIME_RAW_APPROX:
case CLOCK_THREAD_CPUTIME_ID: {
uint64_t ns = clock_gettime_nsec_np(clk_id);
if (!ns) return -1;
tp->tv_sec = ns/NSEC_PER_SEC;
tp->tv_nsec = ns % NSEC_PER_SEC;
return 0;
}
default:
errno = EINVAL;
return -1;
}
}
int
clock_getres(clockid_t clk_id, struct timespec *res)
{
switch(clk_id){
case CLOCK_REALTIME:
case CLOCK_MONOTONIC:
case CLOCK_PROCESS_CPUTIME_ID:
res->tv_nsec = NSEC_PER_USEC;
res->tv_sec = 0;
return 0;
case CLOCK_MONOTONIC_RAW:
case CLOCK_MONOTONIC_RAW_APPROX:
case CLOCK_UPTIME_RAW:
case CLOCK_UPTIME_RAW_APPROX:
case CLOCK_THREAD_CPUTIME_ID: {
mach_timebase_info_data_t tb_info;
if (mach_timebase_info(&tb_info)){
return -1;
}
res->tv_nsec = tb_info.numer / tb_info.denom + (tb_info.numer % tb_info.denom != 0);
res->tv_sec = 0;
return 0;
}
default:
errno = EINVAL;
return -1;
}
}
int
clock_settime(clockid_t clk_id, const struct timespec *tp)
{
switch(clk_id){
case CLOCK_REALTIME: {
struct timeval tv;
TIMESPEC_TO_TIMEVAL(&tv,tp)
return settimeofday(&tv, NULL);
}
default:
errno = EINVAL;
return -1;
}
}