gecko-dev/hal/fallback/FallbackAlarm.cpp

81 lines
1.9 KiB
C++

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