/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */ /* 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/. */ /* * Code to notify things that animate before a refresh, at an appropriate * refresh rate. (Perhaps temporary, until replaced by compositor.) * * Chrome and each tab have their own RefreshDriver, which in turn * hooks into one of a few global timer based on RefreshDriverTimer, * defined below. There are two main global timers -- one for active * animations, and one for inactive ones. These are implemented as * subclasses of RefreshDriverTimer; see below for a description of * their implementations. In the future, additional timer types may * implement things like blocking on vsync. */ #ifdef XP_WIN #include // mmsystem isn't part of WIN32_LEAN_AND_MEAN, so we have // to manually include it #include #endif #include "mozilla/Util.h" #include "nsRefreshDriver.h" #include "nsITimer.h" #include "nsPresContext.h" #include "nsComponentManagerUtils.h" #include "prlog.h" #include "nsAutoPtr.h" #include "nsCSSFrameConstructor.h" #include "nsIDocument.h" #include "nsGUIEvent.h" #include "nsEventDispatcher.h" #include "jsapi.h" #include "nsContentUtils.h" #include "mozilla/Preferences.h" #include "nsViewManager.h" #include "sampler.h" #include "nsNPAPIPluginInstance.h" using mozilla::TimeStamp; using mozilla::TimeDuration; using namespace mozilla; #ifdef PR_LOGGING static PRLogModuleInfo *gLog = nullptr; #define LOG(...) PR_LOG(gLog, PR_LOG_NOTICE, (__VA_ARGS__)) #else #define LOG(...) do { } while(0) #endif #define DEFAULT_FRAME_RATE 60 #define DEFAULT_THROTTLED_FRAME_RATE 1 // after 10 minutes, stop firing off inactive timers #define DEFAULT_INACTIVE_TIMER_DISABLE_SECONDS 600 namespace mozilla { /* * The base class for all global refresh driver timers. It takes care * of managing the list of refresh drivers attached to them and * provides interfaces for querying/setting the rate and actually * running a timer 'Tick'. Subclasses must implement StartTimer(), * StopTimer(), and ScheduleNextTick() -- the first two just * start/stop whatever timer mechanism is in use, and ScheduleNextTick * is called at the start of the Tick() implementation to set a time * for the next tick. */ class RefreshDriverTimer { public: /* * aRate -- the delay, in milliseconds, requested between timer firings */ RefreshDriverTimer(double aRate) { SetRate(aRate); } virtual ~RefreshDriverTimer() { NS_ASSERTION(mRefreshDrivers.Length() == 0, "Should have removed all refresh drivers from here by now!"); } virtual void AddRefreshDriver(nsRefreshDriver* aDriver) { LOG("[%p] AddRefreshDriver %p", this, aDriver); NS_ASSERTION(!mRefreshDrivers.Contains(aDriver), "AddRefreshDriver for a refresh driver that's already in the list!"); mRefreshDrivers.AppendElement(aDriver); if (mRefreshDrivers.Length() == 1) { StartTimer(); } } virtual void RemoveRefreshDriver(nsRefreshDriver* aDriver) { LOG("[%p] RemoveRefreshDriver %p", this, aDriver); NS_ASSERTION(mRefreshDrivers.Contains(aDriver), "RemoveRefreshDriver for a refresh driver that's not in the list!"); mRefreshDrivers.RemoveElement(aDriver); if (mRefreshDrivers.Length() == 0) { StopTimer(); } } double GetRate() const { return mRateMilliseconds; } // will take effect at next timer tick virtual void SetRate(double aNewRate) { mRateMilliseconds = aNewRate; mRateDuration = TimeDuration::FromMilliseconds(mRateMilliseconds); } TimeStamp MostRecentRefresh() const { return mLastFireTime; } int64_t MostRecentRefreshEpochTime() const { return mLastFireEpoch; } protected: virtual void StartTimer() = 0; virtual void StopTimer() = 0; virtual void ScheduleNextTick(TimeStamp aNowTime) = 0; /* * Actually runs a tick, poking all the attached RefreshDrivers. * Grabs the "now" time via JS_Now and TimeStamp::Now(). */ void Tick() { int64_t jsnow = JS_Now(); TimeStamp now = TimeStamp::Now(); ScheduleNextTick(now); mLastFireEpoch = jsnow; mLastFireTime = now; LOG("[%p] ticking drivers...", this); nsTArray > drivers(mRefreshDrivers); for (size_t i = 0; i < drivers.Length(); ++i) { // don't poke this driver if it's in test mode if (drivers[i]->IsTestControllingRefreshesEnabled()) { continue; } TickDriver(drivers[i], jsnow, now); } LOG("[%p] done.", this); } static void TickDriver(nsRefreshDriver* driver, int64_t jsnow, TimeStamp now) { LOG(">> TickDriver: %p (jsnow: %lld)", driver, jsnow); driver->Tick(jsnow, now); } double mRateMilliseconds; TimeDuration mRateDuration; int64_t mLastFireEpoch; TimeStamp mLastFireTime; TimeStamp mTargetTime; nsTArray > mRefreshDrivers; // useful callback for nsITimer-based derived classes, here // bacause of c++ protected shenanigans static void TimerTick(nsITimer* aTimer, void* aClosure) { RefreshDriverTimer *timer = static_cast(aClosure); timer->Tick(); } }; /* * A RefreshDriverTimer that uses a nsITimer as the underlying timer. Note that * this is a ONE_SHOT timer, not a repeating one! Subclasses are expected to * implement ScheduleNextTick and intelligently calculate the next time to tick, * and to reset mTimer. Using a repeating nsITimer gets us into a lot of pain * with its attempt at intelligent slack removal and such, so we don't do it. */ class SimpleTimerBasedRefreshDriverTimer : public RefreshDriverTimer { public: SimpleTimerBasedRefreshDriverTimer(double aRate) : RefreshDriverTimer(aRate) { mTimer = do_CreateInstance(NS_TIMER_CONTRACTID); } virtual ~SimpleTimerBasedRefreshDriverTimer() { StopTimer(); } protected: virtual void StartTimer() { // pretend we just fired, and we schedule the next tick normally mLastFireEpoch = JS_Now(); mLastFireTime = TimeStamp::Now(); mTargetTime = mLastFireTime + mRateDuration; uint32_t delay = static_cast(mRateMilliseconds); mTimer->InitWithFuncCallback(TimerTick, this, delay, nsITimer::TYPE_ONE_SHOT); } virtual void StopTimer() { mTimer->Cancel(); } nsRefPtr mTimer; }; /* * PreciseRefreshDriverTimer schedules ticks based on the current time * and when the next tick -should- be sent if we were hitting our * rate. It always schedules ticks on multiples of aRate -- meaning that * if some execution takes longer than an alloted slot, the next tick * will be delayed instead of triggering instantly. This might not be * desired -- there's an #if 0'd block below that we could put behind * a pref to control this behaviour. */ class PreciseRefreshDriverTimer : public SimpleTimerBasedRefreshDriverTimer { public: PreciseRefreshDriverTimer(double aRate) : SimpleTimerBasedRefreshDriverTimer(aRate) { } protected: virtual void ScheduleNextTick(TimeStamp aNowTime) { // The number of (whole) elapsed intervals between the last target // time and the actual time. We want to truncate the double down // to an int number of intervals. int numElapsedIntervals = static_cast((aNowTime - mTargetTime) / mRateDuration); if (numElapsedIntervals < 0) { // It's possible that numElapsedIntervals is negative (e.g. timer compensation // may result in (aNowTime - mTargetTime) < -1.0/mRateDuration, which will result in // negative numElapsedIntervals), so make sure we don't target the same timestamp. numElapsedIntervals = 0; } // the last "tick" that may or may not have been actually sent was // at this time. For example, if the rate is 15ms, the target // time is 200ms, and it's now 225ms, the last effective tick // would have been at 215ms. The next one should then be // scheduled for 5 ms from now. // // We then add another mRateDuration to find the next tick target. TimeStamp newTarget = mTargetTime + mRateDuration * (numElapsedIntervals + 1); // the amount of (integer) ms until the next time we should tick uint32_t delay = static_cast((newTarget - aNowTime).ToMilliseconds()); // Without this block, we'll always schedule on interval ticks; // with it, we'll schedule immediately if we missed our tick target // last time. #if 0 if (numElapsedIntervals > 0) { // we're late, so reset newTarget = aNowTime; delay = 0; } #endif // log info & lateness LOG("[%p] precise timer last tick late by %f ms, next tick in %d ms", this, (aNowTime - mTargetTime).ToMilliseconds(), delay); // then schedule the timer LOG("[%p] scheduling callback for %d ms (2)", this, delay); mTimer->InitWithFuncCallback(TimerTick, this, delay, nsITimer::TYPE_ONE_SHOT); mTargetTime = newTarget; } }; /* * A RefreshDriverTimer for inactive documents. When a new refresh driver is * added, the rate is reset to the base (normally 1s/1fps). Every time * it ticks, a single refresh driver is poked. Once they have all been poked, * the duration between ticks doubles, up to mDisableAfterMilliseconds. At that point, * the timer is quiet and doesn't tick (until something is added to it again). * * When a timer is removed, there is a possibility of another timer * being skipped for one cycle. We could avoid this by adjusting * mNextDriverIndex in RemoveRefreshDriver, but there's little need to * add that complexity. All we want is for inactive drivers to tick * at some point, but we don't care too much about how often. */ class InactiveRefreshDriverTimer : public RefreshDriverTimer { public: InactiveRefreshDriverTimer(double aRate) : RefreshDriverTimer(aRate), mNextTickDuration(aRate), mDisableAfterMilliseconds(-1.0), mNextDriverIndex(0) { mTimer = do_CreateInstance(NS_TIMER_CONTRACTID); } InactiveRefreshDriverTimer(double aRate, double aDisableAfterMilliseconds) : RefreshDriverTimer(aRate), mNextTickDuration(aRate), mDisableAfterMilliseconds(aDisableAfterMilliseconds), mNextDriverIndex(0) { mTimer = do_CreateInstance(NS_TIMER_CONTRACTID); } virtual void AddRefreshDriver(nsRefreshDriver* aDriver) { RefreshDriverTimer::AddRefreshDriver(aDriver); LOG("[%p] inactive timer got new refresh driver %p, resetting rate", this, aDriver); // reset the timer, and start with the newly added one next time. mNextTickDuration = mRateMilliseconds; // we don't really have to start with the newly added one, but we may as well // not tick the old ones at the fastest rate any more than we need to. mNextDriverIndex = mRefreshDrivers.Length() - 1; StopTimer(); StartTimer(); } protected: virtual void StartTimer() { mLastFireEpoch = JS_Now(); mLastFireTime = TimeStamp::Now(); mTargetTime = mLastFireTime + mRateDuration; uint32_t delay = static_cast(mRateMilliseconds); mTimer->InitWithFuncCallback(TimerTickOne, this, delay, nsITimer::TYPE_ONE_SHOT); } virtual void StopTimer() { mTimer->Cancel(); } virtual void ScheduleNextTick(TimeStamp aNowTime) { if (mDisableAfterMilliseconds > 0.0 && mNextTickDuration > mDisableAfterMilliseconds) { // We hit the time after which we should disable // inactive window refreshes; don't schedule anything // until we get kicked by an AddRefreshDriver call. return; } // double the next tick time if we've already gone through all of them once if (mNextDriverIndex >= mRefreshDrivers.Length()) { mNextTickDuration *= 2.0; mNextDriverIndex = 0; } // this doesn't need to be precise; do a simple schedule uint32_t delay = static_cast(mNextTickDuration); mTimer->InitWithFuncCallback(TimerTickOne, this, delay, nsITimer::TYPE_ONE_SHOT); LOG("[%p] inactive timer next tick in %f ms [index %d/%d]", this, mNextTickDuration, mNextDriverIndex, mRefreshDrivers.Length()); } /* Runs just one driver's tick. */ void TickOne() { int64_t jsnow = JS_Now(); TimeStamp now = TimeStamp::Now(); ScheduleNextTick(now); mLastFireEpoch = jsnow; mLastFireTime = now; nsTArray > drivers(mRefreshDrivers); if (mNextDriverIndex < drivers.Length() && !drivers[mNextDriverIndex]->IsTestControllingRefreshesEnabled()) { TickDriver(drivers[mNextDriverIndex], jsnow, now); } mNextDriverIndex++; } static void TimerTickOne(nsITimer* aTimer, void* aClosure) { InactiveRefreshDriverTimer *timer = static_cast(aClosure); timer->TickOne(); } nsRefPtr mTimer; double mNextTickDuration; double mDisableAfterMilliseconds; uint32_t mNextDriverIndex; }; } // namespace mozilla static PreciseRefreshDriverTimer *sRegularRateTimer = nullptr; static InactiveRefreshDriverTimer *sThrottledRateTimer = nullptr; #ifdef XP_WIN static int32_t sHighPrecisionTimerRequests = 0; // a bare pointer to avoid introducing a static constructor static nsITimer *sDisableHighPrecisionTimersTimer = nullptr; #endif /* static */ void nsRefreshDriver::InitializeStatics() { #ifdef PR_LOGGING if (!gLog) { gLog = PR_NewLogModule("nsRefreshDriver"); } #endif } /* static */ void nsRefreshDriver::Shutdown() { // clean up our timers delete sRegularRateTimer; delete sThrottledRateTimer; sRegularRateTimer = nullptr; sThrottledRateTimer = nullptr; #ifdef XP_WIN if (sDisableHighPrecisionTimersTimer) { sDisableHighPrecisionTimersTimer->Cancel(); NS_RELEASE(sDisableHighPrecisionTimersTimer); timeEndPeriod(1); } else if (sHighPrecisionTimerRequests) { timeEndPeriod(1); } #endif } /* static */ int32_t nsRefreshDriver::DefaultInterval() { return NSToIntRound(1000.0 / DEFAULT_FRAME_RATE); } // Compute the interval to use for the refresh driver timer, in // milliseconds double nsRefreshDriver::GetRegularTimerInterval() const { int32_t rate = Preferences::GetInt("layout.frame_rate", -1); if (rate <= 0) { // TODO: get the rate from the platform rate = DEFAULT_FRAME_RATE; } return 1000.0 / rate; } double nsRefreshDriver::GetThrottledTimerInterval() const { int32_t rate = Preferences::GetInt("layout.throttled_frame_rate", -1); if (rate <= 0) { rate = DEFAULT_THROTTLED_FRAME_RATE; } return 1000.0 / rate; } double nsRefreshDriver::GetRefreshTimerInterval() const { return mThrottled ? GetThrottledTimerInterval() : GetRegularTimerInterval(); } RefreshDriverTimer* nsRefreshDriver::ChooseTimer() const { if (mThrottled) { if (!sThrottledRateTimer) sThrottledRateTimer = new InactiveRefreshDriverTimer(GetThrottledTimerInterval(), DEFAULT_INACTIVE_TIMER_DISABLE_SECONDS * 1000.0); return sThrottledRateTimer; } if (!sRegularRateTimer) sRegularRateTimer = new PreciseRefreshDriverTimer(GetRegularTimerInterval()); return sRegularRateTimer; } nsRefreshDriver::nsRefreshDriver(nsPresContext* aPresContext) : mActiveTimer(nullptr), mPresContext(aPresContext), mFrozen(false), mThrottled(false), mTestControllingRefreshes(false), mViewManagerFlushIsPending(false), mRequestedHighPrecision(false) { mMostRecentRefreshEpochTime = JS_Now(); mMostRecentRefresh = TimeStamp::Now(); mPaintFlashing = Preferences::GetBool("nglayout.debug.paint_flashing"); mRequests.Init(); } nsRefreshDriver::~nsRefreshDriver() { NS_ABORT_IF_FALSE(ObserverCount() == 0, "observers should have unregistered"); NS_ABORT_IF_FALSE(!mActiveTimer, "timer should be gone"); for (uint32_t i = 0; i < mPresShellsToInvalidateIfHidden.Length(); i++) { mPresShellsToInvalidateIfHidden[i]->InvalidatePresShellIfHidden(); } mPresShellsToInvalidateIfHidden.Clear(); } // Method for testing. See nsIDOMWindowUtils.advanceTimeAndRefresh // for description. void nsRefreshDriver::AdvanceTimeAndRefresh(int64_t aMilliseconds) { // ensure that we're removed from our driver StopTimer(); if (!mTestControllingRefreshes) { mMostRecentRefreshEpochTime = JS_Now(); mMostRecentRefresh = TimeStamp::Now(); mTestControllingRefreshes = true; } mMostRecentRefreshEpochTime += aMilliseconds * 1000; mMostRecentRefresh += TimeDuration::FromMilliseconds((double) aMilliseconds); nsCxPusher pusher; pusher.PushNull(); DoTick(); } void nsRefreshDriver::RestoreNormalRefresh() { mTestControllingRefreshes = false; EnsureTimerStarted(false); } TimeStamp nsRefreshDriver::MostRecentRefresh() const { const_cast(this)->EnsureTimerStarted(false); return mMostRecentRefresh; } int64_t nsRefreshDriver::MostRecentRefreshEpochTime() const { const_cast(this)->EnsureTimerStarted(false); return mMostRecentRefreshEpochTime; } bool nsRefreshDriver::AddRefreshObserver(nsARefreshObserver* aObserver, mozFlushType aFlushType) { ObserverArray& array = ArrayFor(aFlushType); bool success = array.AppendElement(aObserver) != nullptr; EnsureTimerStarted(false); return success; } bool nsRefreshDriver::RemoveRefreshObserver(nsARefreshObserver* aObserver, mozFlushType aFlushType) { ObserverArray& array = ArrayFor(aFlushType); return array.RemoveElement(aObserver); } bool nsRefreshDriver::AddImageRequest(imgIRequest* aRequest) { if (!mRequests.PutEntry(aRequest)) { return false; } EnsureTimerStarted(false); return true; } void nsRefreshDriver::RemoveImageRequest(imgIRequest* aRequest) { mRequests.RemoveEntry(aRequest); } void nsRefreshDriver::ClearAllImageRequests() { mRequests.Clear(); } void nsRefreshDriver::EnsureTimerStarted(bool aAdjustingTimer) { if (mTestControllingRefreshes) return; // will it already fire, and no other changes needed? if (mActiveTimer && !aAdjustingTimer) return; if (mFrozen || !mPresContext) { // If we don't want to start it now, or we've been disconnected. StopTimer(); return; } // We got here because we're either adjusting the time *or* we're // starting it for the first time. Add to the right timer, // prehaps removing it from a previously-set one. RefreshDriverTimer *newTimer = ChooseTimer(); if (newTimer != mActiveTimer) { if (mActiveTimer) mActiveTimer->RemoveRefreshDriver(this); mActiveTimer = newTimer; mActiveTimer->AddRefreshDriver(this); } mMostRecentRefresh = mActiveTimer->MostRecentRefresh(); mMostRecentRefreshEpochTime = mActiveTimer->MostRecentRefreshEpochTime(); } void nsRefreshDriver::StopTimer() { if (!mActiveTimer) return; mActiveTimer->RemoveRefreshDriver(this); mActiveTimer = nullptr; if (mRequestedHighPrecision) { SetHighPrecisionTimersEnabled(false); } } #ifdef XP_WIN static void DisableHighPrecisionTimersCallback(nsITimer *aTimer, void *aClosure) { timeEndPeriod(1); NS_RELEASE(sDisableHighPrecisionTimersTimer); } #endif void nsRefreshDriver::ConfigureHighPrecision() { bool haveFrameRequestCallbacks = mFrameRequestCallbackDocs.Length() > 0; // if the only change that's needed is that we need high precision, // then just set that if (!mThrottled && !mRequestedHighPrecision && haveFrameRequestCallbacks) { SetHighPrecisionTimersEnabled(true); } else if (mRequestedHighPrecision && !haveFrameRequestCallbacks) { SetHighPrecisionTimersEnabled(false); } } void nsRefreshDriver::SetHighPrecisionTimersEnabled(bool aEnable) { LOG("[%p] SetHighPrecisionTimersEnabled (%s)", this, aEnable ? "true" : "false"); if (aEnable) { NS_ASSERTION(!mRequestedHighPrecision, "SetHighPrecisionTimersEnabled(true) called when already requested!"); #ifdef XP_WIN if (++sHighPrecisionTimerRequests == 1) { // If we had a timer scheduled to disable it, that means that it's already // enabled; just cancel the timer. Otherwise, really enable it. if (sDisableHighPrecisionTimersTimer) { sDisableHighPrecisionTimersTimer->Cancel(); NS_RELEASE(sDisableHighPrecisionTimersTimer); } else { timeBeginPeriod(1); } } #endif mRequestedHighPrecision = true; } else { NS_ASSERTION(mRequestedHighPrecision, "SetHighPrecisionTimersEnabled(false) called when not requested!"); #ifdef XP_WIN if (--sHighPrecisionTimerRequests == 0) { // Don't jerk us around between high precision and low precision // timers; instead, only allow leaving high precision timers // after 90 seconds. This is arbitrary, but hopefully good // enough. NS_ASSERTION(!sDisableHighPrecisionTimersTimer, "We shouldn't have an outstanding disable-high-precision timer !"); nsCOMPtr timer = do_CreateInstance(NS_TIMER_CONTRACTID); if (timer) { timer.forget(&sDisableHighPrecisionTimersTimer); sDisableHighPrecisionTimersTimer->InitWithFuncCallback(DisableHighPrecisionTimersCallback, nullptr, 90 * 1000, nsITimer::TYPE_ONE_SHOT); } else { // might happen if we're shutting down XPCOM; just drop the time period down // immediately timeEndPeriod(1); } } #endif mRequestedHighPrecision = false; } } uint32_t nsRefreshDriver::ObserverCount() const { uint32_t sum = 0; for (uint32_t i = 0; i < ArrayLength(mObservers); ++i) { sum += mObservers[i].Length(); } // Even while throttled, we need to process layout and style changes. Style // changes can trigger transitions which fire events when they complete, and // layout changes can affect media queries on child documents, triggering // style changes, etc. sum += mStyleFlushObservers.Length(); sum += mLayoutFlushObservers.Length(); sum += mFrameRequestCallbackDocs.Length(); sum += mViewManagerFlushIsPending; return sum; } uint32_t nsRefreshDriver::ImageRequestCount() const { return mRequests.Count(); } nsRefreshDriver::ObserverArray& nsRefreshDriver::ArrayFor(mozFlushType aFlushType) { switch (aFlushType) { case Flush_Style: return mObservers[0]; case Flush_Layout: return mObservers[1]; case Flush_Display: return mObservers[2]; default: NS_ABORT_IF_FALSE(false, "bad flush type"); return *static_cast(nullptr); } } /* * nsISupports implementation */ NS_IMPL_ISUPPORTS1(nsRefreshDriver, nsISupports) /* * nsITimerCallback implementation */ void nsRefreshDriver::DoTick() { NS_PRECONDITION(!mFrozen, "Why are we notified while frozen?"); NS_PRECONDITION(mPresContext, "Why are we notified after disconnection?"); NS_PRECONDITION(!nsContentUtils::GetCurrentJSContext(), "Shouldn't have a JSContext on the stack"); if (mTestControllingRefreshes) { Tick(mMostRecentRefreshEpochTime, mMostRecentRefresh); } else { Tick(JS_Now(), TimeStamp::Now()); } } void nsRefreshDriver::Tick(int64_t aNowEpoch, TimeStamp aNowTime) { NS_PRECONDITION(!nsContentUtils::GetCurrentJSContext(), "Shouldn't have a JSContext on the stack"); if (nsNPAPIPluginInstance::InPluginCallUnsafeForReentry()) { NS_ERROR("Refresh driver should not run during plugin call!"); // Try to survive this by just ignoring the refresh tick. return; } SAMPLE_LABEL("nsRefreshDriver", "Tick"); // We're either frozen or we were disconnected (likely in the middle // of a tick iteration). Just do nothing here, since our // prescontext went away. if (mFrozen || !mPresContext) { return; } mMostRecentRefresh = aNowTime; mMostRecentRefreshEpochTime = aNowEpoch; nsCOMPtr presShell = mPresContext->GetPresShell(); if (!presShell || (ObserverCount() == 0 && ImageRequestCount() == 0)) { // Things are being destroyed, or we no longer have any observers. // We don't want to stop the timer when observers are initially // removed, because sometimes observers can be added and removed // often depending on what other things are going on and in that // situation we don't want to thrash our timer. So instead we // wait until we get a Notify() call when we have no observers // before stopping the timer. StopTimer(); return; } /* * The timer holds a reference to |this| while calling |Notify|. * However, implementations of |WillRefresh| are permitted to destroy * the pres context, which will cause our |mPresContext| to become * null. If this happens, we must stop notifying observers. */ for (uint32_t i = 0; i < ArrayLength(mObservers); ++i) { ObserverArray::EndLimitedIterator etor(mObservers[i]); while (etor.HasMore()) { nsRefPtr obs = etor.GetNext(); obs->WillRefresh(aNowTime); if (!mPresContext || !mPresContext->GetPresShell()) { StopTimer(); return; } } if (i == 0) { // Grab all of our frame request callbacks up front. nsIDocument::FrameRequestCallbackList frameRequestCallbacks; for (uint32_t i = 0; i < mFrameRequestCallbackDocs.Length(); ++i) { mFrameRequestCallbackDocs[i]-> TakeFrameRequestCallbacks(frameRequestCallbacks); } // OK, now reset mFrameRequestCallbackDocs so they can be // readded as needed. mFrameRequestCallbackDocs.Clear(); int64_t eventTime = aNowEpoch / PR_USEC_PER_MSEC; for (uint32_t i = 0; i < frameRequestCallbacks.Length(); ++i) { nsAutoMicroTask mt; frameRequestCallbacks[i]->Sample(eventTime); } // This is the Flush_Style case. if (mPresContext && mPresContext->GetPresShell()) { nsAutoTArray observers; observers.AppendElements(mStyleFlushObservers); for (uint32_t j = observers.Length(); j && mPresContext && mPresContext->GetPresShell(); --j) { // Make sure to not process observers which might have been removed // during previous iterations. nsIPresShell* shell = observers[j - 1]; if (!mStyleFlushObservers.Contains(shell)) continue; NS_ADDREF(shell); mStyleFlushObservers.RemoveElement(shell); shell->FrameConstructor()->mObservingRefreshDriver = false; shell->FlushPendingNotifications(ChangesToFlush(Flush_Style, false)); NS_RELEASE(shell); } } } else if (i == 1) { // This is the Flush_Layout case. if (mPresContext && mPresContext->GetPresShell()) { nsAutoTArray observers; observers.AppendElements(mLayoutFlushObservers); for (uint32_t j = observers.Length(); j && mPresContext && mPresContext->GetPresShell(); --j) { // Make sure to not process observers which might have been removed // during previous iterations. nsIPresShell* shell = observers[j - 1]; if (!mLayoutFlushObservers.Contains(shell)) continue; NS_ADDREF(shell); mLayoutFlushObservers.RemoveElement(shell); shell->mReflowScheduled = false; shell->mSuppressInterruptibleReflows = false; shell->FlushPendingNotifications(ChangesToFlush(Flush_InterruptibleLayout, false)); NS_RELEASE(shell); } } } } /* * Perform notification to imgIRequests subscribed to listen * for refresh events. */ ImageRequestParameters parms = {aNowTime}; if (mRequests.Count()) { mRequests.EnumerateEntries(nsRefreshDriver::ImageRequestEnumerator, &parms); } for (uint32_t i = 0; i < mPresShellsToInvalidateIfHidden.Length(); i++) { mPresShellsToInvalidateIfHidden[i]->InvalidatePresShellIfHidden(); } mPresShellsToInvalidateIfHidden.Clear(); if (mViewManagerFlushIsPending) { #ifdef DEBUG_INVALIDATIONS printf("Starting ProcessPendingUpdates\n"); #endif #ifndef MOZ_WIDGET_GONK // Waiting for bug 830475 to work on B2G. nsRefPtr mgr = mPresContext->GetPresShell()->GetLayerManager(); if (mgr) { mgr->SetPaintStartTime(mMostRecentRefresh); } #endif mViewManagerFlushIsPending = false; nsRefPtr vm = mPresContext->GetPresShell()->GetViewManager(); vm->ProcessPendingUpdates(); #ifdef DEBUG_INVALIDATIONS printf("Ending ProcessPendingUpdates\n"); #endif } } PLDHashOperator nsRefreshDriver::ImageRequestEnumerator(nsISupportsHashKey* aEntry, void* aUserArg) { ImageRequestParameters* parms = static_cast (aUserArg); mozilla::TimeStamp mostRecentRefresh = parms->ts; imgIRequest* req = static_cast(aEntry->GetKey()); NS_ABORT_IF_FALSE(req, "Unable to retrieve the image request"); nsCOMPtr image; if (NS_SUCCEEDED(req->GetImage(getter_AddRefs(image)))) { image->RequestRefresh(mostRecentRefresh); } return PL_DHASH_NEXT; } void nsRefreshDriver::Freeze() { NS_ASSERTION(!mFrozen, "Freeze called on already-frozen refresh driver"); StopTimer(); mFrozen = true; } void nsRefreshDriver::Thaw() { NS_ASSERTION(mFrozen, "Thaw called on an unfrozen refresh driver"); mFrozen = false; if (ObserverCount() || ImageRequestCount()) { // FIXME: This isn't quite right, since our EnsureTimerStarted call // updates our mMostRecentRefresh, but the DoRefresh call won't run // and notify our observers until we get back to the event loop. // Thus MostRecentRefresh() will lie between now and the DoRefresh. NS_DispatchToCurrentThread(NS_NewRunnableMethod(this, &nsRefreshDriver::DoRefresh)); EnsureTimerStarted(false); } } void nsRefreshDriver::SetThrottled(bool aThrottled) { if (aThrottled != mThrottled) { mThrottled = aThrottled; if (mActiveTimer) { // We want to switch our timer type here, so just stop and // restart the timer. EnsureTimerStarted(true); } } } void nsRefreshDriver::DoRefresh() { // Don't do a refresh unless we're in a state where we should be refreshing. if (!mFrozen && mPresContext && mActiveTimer) { DoTick(); } } #ifdef DEBUG bool nsRefreshDriver::IsRefreshObserver(nsARefreshObserver* aObserver, mozFlushType aFlushType) { ObserverArray& array = ArrayFor(aFlushType); return array.Contains(aObserver); } #endif void nsRefreshDriver::ScheduleViewManagerFlush() { NS_ASSERTION(mPresContext->IsRoot(), "Should only schedule view manager flush on root prescontexts"); mViewManagerFlushIsPending = true; EnsureTimerStarted(false); } void nsRefreshDriver::ScheduleFrameRequestCallbacks(nsIDocument* aDocument) { NS_ASSERTION(mFrameRequestCallbackDocs.IndexOf(aDocument) == mFrameRequestCallbackDocs.NoIndex, "Don't schedule the same document multiple times"); mFrameRequestCallbackDocs.AppendElement(aDocument); // make sure that the timer is running ConfigureHighPrecision(); EnsureTimerStarted(false); } void nsRefreshDriver::RevokeFrameRequestCallbacks(nsIDocument* aDocument) { mFrameRequestCallbackDocs.RemoveElement(aDocument); ConfigureHighPrecision(); // No need to worry about restarting our timer in slack mode if it's already // running; that will happen automatically when it fires. }