Function startTimer

src/libdecaf/src/ios/kernel/ios_kernel_timer.cpp:312–364

* Put the timer into the running timer list. * * \return * Returns the position of the timer in the queue, if the position is 0 then * the new timer will be the first one to trigger in which case the caller * is responsbile for updating the next interrupt time. */

 * is responsbile for updating the next interrupt time.
 */
uint32_t
startTimer(phys_ptr<Timer> timer)
{
   auto &timerManager = sData->timerManager;
   auto timerQueuePosition = 0u;

   // Insert timer into the running timer list ordered by nextTriggerTime.
   if (timerManager.firstRunningTimerIdx < 0) {
      timerManager.firstRunningTimerIdx = timer->index;
      timerManager.lastRunningTimerIdx = timer->index;

      timer->prevTimerIdx = int16_t { -1 };
      timer->nextTimerIdx = int16_t { -1 };
   } else {
      auto prevTimerIdx = int16_t { -1 };
      auto nextTimerIdx = int16_t { -1 };
      auto itrTimerIdx = timerManager.firstRunningTimerIdx;

      while (itrTimerIdx >= 0) {
         const auto &itrTimer = timerManager.timers[itrTimerIdx];
         if (itrTimer.nextTriggerTime >= timer->nextTriggerTime) {
            break;
         }

         itrTimerIdx = itrTimer.nextTimerIdx;
         timerQueuePosition++;
      }

      if (prevTimerIdx < 0) {
         nextTimerIdx = timerManager.firstRunningTimerIdx;
         timerManager.firstRunningTimerIdx = timer->index;
      } else {
         auto &prevTimer = timerManager.timers[prevTimerIdx];
         nextTimerIdx = prevTimer.nextTimerIdx;
         prevTimer.nextTimerIdx = timer->index;
      }

      if (nextTimerIdx < 0) {
         decaf_check(timerManager.lastRunningTimerIdx == prevTimerIdx);
         timerManager.lastRunningTimerIdx = timer->index;
      } else {
         auto &nextTimer = timerManager.timers[nextTimerIdx];
         nextTimer.prevTimerIdx = timer->index;
      }

      timer->prevTimerIdx = prevTimerIdx;
      timer->nextTimerIdx = nextTimerIdx;
   }

   timer->state = TimerState::Running;
   timerManager.numRunningTimers++;
   return timerQueuePosition;
}

Error
stopTimer(phys_ptr<Timer> timer)