michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "Hal.h"
michael@0: 
michael@0: #include <algorithm>
michael@0: 
michael@0: #include "mozilla/ClearOnShutdown.h"
michael@0: #include "mozilla/StaticPtr.h"
michael@0: #include "nsComponentManagerUtils.h"
michael@0: #include "nsITimer.h"
michael@0: #include "nsThreadUtils.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace hal_impl {
michael@0: 
michael@0: static void
michael@0: TimerCallbackFunc(nsITimer *aTimer, void *aClosure)
michael@0: {
michael@0:   hal::NotifyAlarmFired();
michael@0: }
michael@0: 
michael@0: static StaticRefPtr<nsITimer> sTimer;
michael@0: 
michael@0: bool
michael@0: EnableAlarm()
michael@0: {
michael@0:   static bool initialized = false;
michael@0:   if (!initialized) {
michael@0:     initialized = true;
michael@0:     ClearOnShutdown(&sTimer);
michael@0:   }
michael@0: 
michael@0:   nsCOMPtr<nsITimer> timer = do_CreateInstance("@mozilla.org/timer;1");
michael@0:   sTimer = timer;
michael@0:   MOZ_ASSERT(sTimer);
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: void
michael@0: DisableAlarm()
michael@0: {
michael@0:   /*
michael@0:    * DisableAlarm() may be called after sTimer has been set to null by
michael@0:    * ClearOnShutdown().
michael@0:    */
michael@0:   if (sTimer) {
michael@0:     sTimer->Cancel();
michael@0:   }
michael@0: }
michael@0: 
michael@0: bool
michael@0: SetAlarm(int32_t aSeconds, int32_t aNanoseconds)
michael@0: {
michael@0:   if (!sTimer) {
michael@0:     HAL_LOG(("We should have enabled the alarm"));
michael@0:     MOZ_ASSERT(false);
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   // Do the math to convert aSeconds and aNanoseconds into milliseconds since
michael@0:   // the epoch.
michael@0:   int64_t milliseconds = static_cast<int64_t>(aSeconds) * 1000 +
michael@0:                          static_cast<int64_t>(aNanoseconds) / 1000000;
michael@0: 
michael@0:   // nsITimer expects relative milliseconds.
michael@0:   int64_t relMilliseconds = milliseconds - PR_Now() / 1000;
michael@0: 
michael@0:   // If the alarm time is in the past relative to PR_Now(),
michael@0:   // we choose to immediately fire the alarm. Passing 0 means nsITimer will
michael@0:   // queue a timeout event immediately.
michael@0:   sTimer->InitWithFuncCallback(TimerCallbackFunc, nullptr,
michael@0:                                clamped<int64_t>(relMilliseconds, 0, INT32_MAX),
michael@0:                                nsITimer::TYPE_ONE_SHOT);
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: } // hal_impl
michael@0: } // namespace mozilla