void Delay_usec(uint32 usec)
{
int was_error;
#if defined(USE_NANOSLEEP)
struct timespec elapsed, tv;
#elif defined(USE_COND_TIMEDWAIT)
// Use a local mutex and cv, so threads remain independent
pthread_cond_t delay_cond = PTHREAD_COND_INITIALIZER;
pthread_mutex_t delay_mutex = PTHREAD_MUTEX_INITIALIZER;
struct timespec elapsed;
uint64 future;
#else
struct timeval tv;
#ifndef SELECT_SETS_REMAINING
uint64 then, now, elapsed;
#endif
#endif
// Set the timeout interval - Linux only needs to do this once
#if defined(SELECT_SETS_REMAINING)
tv.tv_sec = 0;
tv.tv_usec = usec;
#elif defined(USE_NANOSLEEP)
elapsed.tv_sec = 0;
elapsed.tv_nsec = usec * 1000;
#elif defined(USE_COND_TIMEDWAIT)
future = GetTicks_usec() + usec;
elapsed.tv_sec = future / 1000000;
elapsed.tv_nsec = (future % 1000000) * 1000;
#else
then = GetTicks_usec();
#endif
do {
errno = 0;
#if defined(USE_NANOSLEEP)
tv.tv_sec = elapsed.tv_sec;
tv.tv_nsec = elapsed.tv_nsec;
was_error = nanosleep(&tv, &elapsed);
#elif defined(USE_COND_TIMEDWAIT)
was_error = pthread_mutex_lock(&delay_mutex);
was_error = pthread_cond_timedwait(&delay_cond, &delay_mutex, &elapsed);
was_error = pthread_mutex_unlock(&delay_mutex);
#else
#ifndef SELECT_SETS_REMAINING
// Calculate the time interval left (in case of interrupt)
now = GetTicks_usec();
elapsed = now - then;
then = now;
if (elapsed >= usec)
break;
usec -= elapsed;
tv.tv_sec = 0;
tv.tv_usec = usec;
#endif
was_error = select(0, NULL, NULL, NULL, &tv);
#endif
} while (was_error && (errno == EINTR));
}
static DWORD WINAPI tick_func(void *arg)
{
int tick_counter = 0;
uint64 start = GetTicks_usec();
int64 ticks = 0;
uint64 next = GetTicks_usec();
while (!tick_thread_cancel) {
// Wait
next += 16625;
int64 delay = next - GetTicks_usec();
if (delay > 0)
Delay_usec(delay);
else if (delay < -16625)
next = GetTicks_usec();
ticks++;
// Pseudo Mac 1Hz interrupt, update local time
if (++tick_counter > 60) {
tick_counter = 0;
WriteMacInt32(0x20c, TimerDateTime());
}
// Trigger 60Hz interrupt
if (ReadMacInt32(XLM_IRQ_NEST) == 0) {
SetInterruptFlag(INTFLAG_VIA);
TriggerInterrupt();
}
}
uint64 end = GetTicks_usec();
D(bug("%lu ticks in %lu usec = %f ticks/sec\n", (unsigned long)ticks, (unsigned long)(end - start), ticks * 1000000.0 / (end - start)));
return 0;
}
void Delay_usec(uint32 usec)
{
#ifdef __unix__
int was_error;
#ifndef __linux__ /* Non-Linux implementations need to calculate time left */
uint64 then, now, elapsed;
#endif
struct timeval tv;
/* Set the timeout interval - Linux only needs to do this once */
#ifdef __linux__
tv.tv_sec = 0;
tv.tv_usec = usec;
#else
then = GetTicks_usec();
#endif
do {
errno = 0;
#ifndef __linux__
/* Calculate the time interval left (in case of interrupt) */
now = GetTicks_usec();
elapsed = (now-then);
then = now;
if ( elapsed >= usec ) {
break;
}
usec -= elapsed;
tv.tv_sec = 0;
tv.tv_usec = usec;
#endif
was_error = select(0, NULL, NULL, NULL, &tv);
} while (was_error && (errno == EINTR));
#else
SDL_Delay(usec / 1000);
#endif
}
