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-rw-r--r--src/libs/xpcom18a4/xpcom/threads/nsTimerImpl.cpp642
1 files changed, 642 insertions, 0 deletions
diff --git a/src/libs/xpcom18a4/xpcom/threads/nsTimerImpl.cpp b/src/libs/xpcom18a4/xpcom/threads/nsTimerImpl.cpp
new file mode 100644
index 00000000..dc19452f
--- /dev/null
+++ b/src/libs/xpcom18a4/xpcom/threads/nsTimerImpl.cpp
@@ -0,0 +1,642 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 2001
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ * Stuart Parmenter <pavlov@netscape.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsTimerImpl.h"
+#include "TimerThread.h"
+#include "nsAutoLock.h"
+
+#include "nsVoidArray.h"
+
+#include "nsIEventQueue.h"
+
+#include "prmem.h"
+
+static PRInt32 gGenerator = 0;
+static TimerThread* gThread = nsnull;
+static PRBool gFireOnIdle = PR_FALSE;
+static nsTimerManager* gManager = nsnull;
+
+#ifdef DEBUG_TIMERS
+#include <math.h>
+
+double nsTimerImpl::sDeltaSumSquared = 0;
+double nsTimerImpl::sDeltaSum = 0;
+double nsTimerImpl::sDeltaNum = 0;
+
+static void
+myNS_MeanAndStdDev(double n, double sumOfValues, double sumOfSquaredValues,
+ double *meanResult, double *stdDevResult)
+{
+ double mean = 0.0, var = 0.0, stdDev = 0.0;
+ if (n > 0.0 && sumOfValues >= 0) {
+ mean = sumOfValues / n;
+ double temp = (n * sumOfSquaredValues) - (sumOfValues * sumOfValues);
+ if (temp < 0.0 || n <= 1)
+ var = 0.0;
+ else
+ var = temp / (n * (n - 1));
+ // for some reason, Windows says sqrt(0.0) is "-1.#J" (?!) so do this:
+ stdDev = var != 0.0 ? sqrt(var) : 0.0;
+ }
+ *meanResult = mean;
+ *stdDevResult = stdDev;
+}
+#endif
+
+NS_IMPL_THREADSAFE_QUERY_INTERFACE2(nsTimerImpl, nsITimer, nsITimerInternal)
+NS_IMPL_THREADSAFE_ADDREF(nsTimerImpl)
+
+NS_IMETHODIMP_(nsrefcnt) nsTimerImpl::Release(void)
+{
+ nsrefcnt count;
+
+ NS_PRECONDITION(0 != mRefCnt, "dup release");
+ count = PR_AtomicDecrement((PRInt32 *)&mRefCnt);
+ NS_LOG_RELEASE(this, count, "nsTimerImpl");
+ if (count == 0) {
+ mRefCnt = 1; /* stabilize */
+
+ /* enable this to find non-threadsafe destructors: */
+ /* NS_ASSERT_OWNINGTHREAD(nsTimerImpl); */
+ NS_DELETEXPCOM(this);
+ return 0;
+ }
+
+ // If only one reference remains, and mArmed is set, then the ref must be
+ // from the TimerThread::mTimers array, so we Cancel this timer to remove
+ // the mTimers element, and return 0 if Cancel in fact disarmed the timer.
+ //
+ // We use an inlined version of nsTimerImpl::Cancel here to check for the
+ // NS_ERROR_NOT_AVAILABLE code returned by gThread->RemoveTimer when this
+ // timer is not found in the mTimers array -- i.e., when the timer was not
+ // in fact armed once we acquired TimerThread::mLock, in spite of mArmed
+ // being true here. That can happen if the armed timer is being fired by
+ // TimerThread::Run as we race and test mArmed just before it is cleared by
+ // the timer thread. If the RemoveTimer call below doesn't find this timer
+ // in the mTimers array, then the last ref to this timer is held manually
+ // and temporarily by the TimerThread, so we should fall through to the
+ // final return and return 1, not 0.
+ //
+ // The original version of this thread-based timer code kept weak refs from
+ // TimerThread::mTimers, removing this timer's weak ref in the destructor,
+ // but that leads to double-destructions in the race described above, and
+ // adding mArmed doesn't help, because destructors can't be deferred, once
+ // begun. But by combining reference-counting and a specialized Release
+ // method with "is this timer still in the mTimers array once we acquire
+ // the TimerThread's lock" testing, we defer destruction until we're sure
+ // that only one thread has its hot little hands on this timer.
+ //
+ // Note that both approaches preclude a timer creator, and everyone else
+ // except the TimerThread who might have a strong ref, from dropping all
+ // their strong refs without implicitly canceling the timer. Timers need
+ // non-mTimers-element strong refs to stay alive.
+
+ if (count == 1 && mArmed) {
+ mCanceled = PR_TRUE;
+
+ if (NS_SUCCEEDED(gThread->RemoveTimer(this)))
+ return 0;
+ }
+
+ return count;
+}
+
+nsTimerImpl::nsTimerImpl() :
+ mClosure(nsnull),
+ mCallbackType(CALLBACK_TYPE_UNKNOWN),
+ mIdle(PR_TRUE),
+ mFiring(PR_FALSE),
+ mArmed(PR_FALSE),
+ mCanceled(PR_FALSE),
+ mGeneration(0),
+ mDelay(0),
+ mTimeout(0)
+{
+ // XXXbsmedberg: shouldn't this be in Init()?
+ nsIThread::GetCurrent(getter_AddRefs(mCallingThread));
+
+ mCallback.c = nsnull;
+
+#ifdef DEBUG_TIMERS
+ mStart = 0;
+ mStart2 = 0;
+#endif
+}
+
+nsTimerImpl::~nsTimerImpl()
+{
+ ReleaseCallback();
+}
+
+//static
+nsresult
+nsTimerImpl::Startup()
+{
+ nsresult rv;
+
+ gThread = new TimerThread();
+ if (!gThread) return NS_ERROR_OUT_OF_MEMORY;
+
+ NS_ADDREF(gThread);
+ rv = gThread->InitLocks();
+
+ if (NS_FAILED(rv)) {
+ NS_RELEASE(gThread);
+ }
+
+ return rv;
+}
+
+void nsTimerImpl::Shutdown()
+{
+#ifdef DEBUG_TIMERS
+ if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
+ double mean = 0, stddev = 0;
+ myNS_MeanAndStdDev(sDeltaNum, sDeltaSum, sDeltaSumSquared, &mean, &stddev);
+
+ PR_LOG(gTimerLog, PR_LOG_DEBUG, ("sDeltaNum = %f, sDeltaSum = %f, sDeltaSumSquared = %f\n", sDeltaNum, sDeltaSum, sDeltaSumSquared));
+ PR_LOG(gTimerLog, PR_LOG_DEBUG, ("mean: %fms, stddev: %fms\n", mean, stddev));
+ }
+#endif
+
+ if (!gThread)
+ return;
+
+ gThread->Shutdown();
+ NS_RELEASE(gThread);
+
+ gFireOnIdle = PR_FALSE;
+}
+
+
+nsresult nsTimerImpl::InitCommon(PRUint32 aType, PRUint32 aDelay)
+{
+ nsresult rv;
+
+ NS_ENSURE_TRUE(gThread, NS_ERROR_NOT_INITIALIZED);
+
+ rv = gThread->Init();
+ NS_ENSURE_SUCCESS(rv, rv);
+
+ /**
+ * In case of re-Init, both with and without a preceding Cancel, clear the
+ * mCanceled flag and assign a new mGeneration. But first, remove any armed
+ * timer from the timer thread's list.
+ *
+ * If we are racing with the timer thread to remove this timer and we lose,
+ * the RemoveTimer call made here will fail to find this timer in the timer
+ * thread's list, and will return false harmlessly. We test mArmed here to
+ * avoid the small overhead in RemoveTimer of locking the timer thread and
+ * checking its list for this timer. It's safe to test mArmed even though
+ * it might be cleared on another thread in the next cycle (or even already
+ * be cleared by another CPU whose store hasn't reached our CPU's cache),
+ * because RemoveTimer is idempotent.
+ */
+ if (mArmed)
+ gThread->RemoveTimer(this);
+ mCanceled = PR_FALSE;
+ mGeneration = PR_AtomicIncrement(&gGenerator);
+
+ mType = (PRUint8)aType;
+ SetDelayInternal(aDelay);
+
+ return gThread->AddTimer(this);
+}
+
+NS_IMETHODIMP nsTimerImpl::InitWithFuncCallback(nsTimerCallbackFunc aFunc,
+ void *aClosure,
+ PRUint32 aDelay,
+ PRUint32 aType)
+{
+ ReleaseCallback();
+ mCallbackType = CALLBACK_TYPE_FUNC;
+ mCallback.c = aFunc;
+ mClosure = aClosure;
+
+ return InitCommon(aType, aDelay);
+}
+
+NS_IMETHODIMP nsTimerImpl::InitWithCallback(nsITimerCallback *aCallback,
+ PRUint32 aDelay,
+ PRUint32 aType)
+{
+ ReleaseCallback();
+ mCallbackType = CALLBACK_TYPE_INTERFACE;
+ mCallback.i = aCallback;
+ NS_ADDREF(mCallback.i);
+
+ return InitCommon(aType, aDelay);
+}
+
+NS_IMETHODIMP nsTimerImpl::Init(nsIObserver *aObserver,
+ PRUint32 aDelay,
+ PRUint32 aType)
+{
+ ReleaseCallback();
+ mCallbackType = CALLBACK_TYPE_OBSERVER;
+ mCallback.o = aObserver;
+ NS_ADDREF(mCallback.o);
+
+ return InitCommon(aType, aDelay);
+}
+
+NS_IMETHODIMP nsTimerImpl::Cancel()
+{
+ mCanceled = PR_TRUE;
+
+ if (gThread)
+ gThread->RemoveTimer(this);
+
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerImpl::SetDelay(PRUint32 aDelay)
+{
+ // If we're already repeating precisely, update mTimeout now so that the
+ // new delay takes effect in the future.
+ if (mTimeout != 0 && mType == TYPE_REPEATING_PRECISE)
+ mTimeout = PR_IntervalNow();
+
+ SetDelayInternal(aDelay);
+
+ if (!mFiring && gThread)
+ gThread->TimerDelayChanged(this);
+
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerImpl::GetDelay(PRUint32* aDelay)
+{
+ *aDelay = mDelay;
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerImpl::SetType(PRUint32 aType)
+{
+ mType = (PRUint8)aType;
+ // XXX if this is called, we should change the actual type.. this could effect
+ // repeating timers. we need to ensure in Fire() that if mType has changed
+ // during the callback that we don't end up with the timer in the queue twice.
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerImpl::GetType(PRUint32* aType)
+{
+ *aType = mType;
+ return NS_OK;
+}
+
+
+NS_IMETHODIMP nsTimerImpl::GetClosure(void** aClosure)
+{
+ *aClosure = mClosure;
+ return NS_OK;
+}
+
+
+NS_IMETHODIMP nsTimerImpl::GetIdle(PRBool *aIdle)
+{
+ *aIdle = mIdle;
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerImpl::SetIdle(PRBool aIdle)
+{
+ mIdle = aIdle;
+ return NS_OK;
+}
+
+void nsTimerImpl::Fire()
+{
+ if (mCanceled)
+ return;
+
+ PRIntervalTime now = PR_IntervalNow();
+#ifdef DEBUG_TIMERS
+ if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
+ PRIntervalTime a = now - mStart; // actual delay in intervals
+ PRUint32 b = PR_MillisecondsToInterval(mDelay); // expected delay in intervals
+ PRUint32 d = PR_IntervalToMilliseconds((a > b) ? a - b : b - a); // delta in ms
+ sDeltaSum += d;
+ sDeltaSumSquared += double(d) * double(d);
+ sDeltaNum++;
+
+ PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] expected delay time %4dms\n", this, mDelay));
+ PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] actual delay time %4dms\n", this, PR_IntervalToMilliseconds(a)));
+ PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] (mType is %d) -------\n", this, mType));
+ PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] delta %4dms\n", this, (a > b) ? (PRInt32)d : -(PRInt32)d));
+
+ mStart = mStart2;
+ mStart2 = 0;
+ }
+#endif
+
+ PRIntervalTime timeout = mTimeout;
+ if (mType == TYPE_REPEATING_PRECISE) {
+ // Precise repeating timers advance mTimeout by mDelay without fail before
+ // calling Fire().
+ timeout -= PR_MillisecondsToInterval(mDelay);
+ }
+ gThread->UpdateFilter(mDelay, timeout, now);
+
+ mFiring = PR_TRUE;
+
+ switch (mCallbackType) {
+ case CALLBACK_TYPE_FUNC:
+ mCallback.c(this, mClosure);
+ break;
+ case CALLBACK_TYPE_INTERFACE:
+ mCallback.i->Notify(this);
+ break;
+ case CALLBACK_TYPE_OBSERVER:
+ mCallback.o->Observe(NS_STATIC_CAST(nsITimer*,this),
+ NS_TIMER_CALLBACK_TOPIC,
+ nsnull);
+ break;
+ default:;
+ }
+
+ mFiring = PR_FALSE;
+
+#ifdef DEBUG_TIMERS
+ if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
+ PR_LOG(gTimerLog, PR_LOG_DEBUG,
+ ("[this=%p] Took %dms to fire timer callback\n",
+ this, PR_IntervalToMilliseconds(PR_IntervalNow() - now)));
+ }
+#endif
+
+ if (mType == TYPE_REPEATING_SLACK) {
+ SetDelayInternal(mDelay); // force mTimeout to be recomputed.
+ if (gThread)
+ gThread->AddTimer(this);
+ }
+}
+
+
+struct TimerEventType : public PLEvent {
+ PRInt32 mGeneration;
+#ifdef DEBUG_TIMERS
+ PRIntervalTime mInitTime;
+#endif
+};
+
+
+void* handleTimerEvent(TimerEventType* event)
+{
+ nsTimerImpl* timer = NS_STATIC_CAST(nsTimerImpl*, event->owner);
+ if (event->mGeneration != timer->GetGeneration())
+ return nsnull;
+
+#ifdef DEBUG_TIMERS
+ if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
+ PRIntervalTime now = PR_IntervalNow();
+ PR_LOG(gTimerLog, PR_LOG_DEBUG,
+ ("[this=%p] time between PostTimerEvent() and Fire(): %dms\n",
+ event->owner, PR_IntervalToMilliseconds(now - event->mInitTime)));
+ }
+#endif
+
+ if (gFireOnIdle) {
+ PRBool idle = PR_FALSE;
+ timer->GetIdle(&idle);
+ if (idle) {
+ NS_ASSERTION(gManager, "Global Thread Manager is null!");
+ if (gManager)
+ gManager->AddIdleTimer(timer);
+ return nsnull;
+ }
+ }
+
+ timer->Fire();
+
+ return nsnull;
+}
+
+void destroyTimerEvent(TimerEventType* event)
+{
+ nsTimerImpl *timer = NS_STATIC_CAST(nsTimerImpl*, event->owner);
+ NS_RELEASE(timer);
+ PR_DELETE(event);
+}
+
+
+void nsTimerImpl::PostTimerEvent()
+{
+ // XXX we may want to reuse the PLEvent in the case of repeating timers.
+ TimerEventType* event;
+
+ // construct
+ event = PR_NEW(TimerEventType);
+ if (!event)
+ return;
+
+ // initialize
+ PL_InitEvent((PLEvent*)event, this,
+ (PLHandleEventProc)handleTimerEvent,
+ (PLDestroyEventProc)destroyTimerEvent);
+
+ // Since TimerThread addref'd 'this' for us, we don't need to addref here.
+ // We will release in destroyMyEvent. We do need to copy the generation
+ // number from this timer into the event, so we can avoid firing a timer
+ // that was re-initialized after being canceled.
+ event->mGeneration = mGeneration;
+
+#ifdef DEBUG_TIMERS
+ if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
+ event->mInitTime = PR_IntervalNow();
+ }
+#endif
+
+ // If this is a repeating precise timer, we need to calculate the time for
+ // the next timer to fire before we make the callback.
+ if (mType == TYPE_REPEATING_PRECISE) {
+ SetDelayInternal(mDelay);
+ if (gThread)
+ gThread->AddTimer(this);
+ }
+
+ PRThread *thread;
+ nsresult rv = mCallingThread->GetPRThread(&thread);
+ if (NS_FAILED(rv)) {
+ NS_WARNING("Dropping timer event because thread is dead");
+ return;
+ }
+
+ nsCOMPtr<nsIEventQueue> queue;
+ if (gThread)
+ gThread->mEventQueueService->GetThreadEventQueue(thread, getter_AddRefs(queue));
+ if (queue)
+ queue->PostEvent(event);
+}
+
+void nsTimerImpl::SetDelayInternal(PRUint32 aDelay)
+{
+ PRIntervalTime delayInterval = PR_MillisecondsToInterval(aDelay);
+ if (delayInterval > DELAY_INTERVAL_MAX) {
+ delayInterval = DELAY_INTERVAL_MAX;
+ aDelay = PR_IntervalToMilliseconds(delayInterval);
+ }
+
+ mDelay = aDelay;
+
+ PRIntervalTime now = PR_IntervalNow();
+ if (mTimeout == 0 || mType != TYPE_REPEATING_PRECISE)
+ mTimeout = now;
+
+ mTimeout += delayInterval;
+
+#ifdef DEBUG_TIMERS
+ if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
+ if (mStart == 0)
+ mStart = now;
+ else
+ mStart2 = now;
+ }
+#endif
+}
+
+/**
+ * Timer Manager code
+ */
+
+NS_IMPL_THREADSAFE_ISUPPORTS1(nsTimerManager, nsITimerManager)
+
+nsTimerManager::nsTimerManager()
+{
+ mLock = PR_NewLock();
+ gManager = this;
+}
+
+nsTimerManager::~nsTimerManager()
+{
+ gManager = nsnull;
+ PR_DestroyLock(mLock);
+
+ nsTimerImpl *theTimer;
+ PRInt32 count = mIdleTimers.Count();
+
+ for (PRInt32 i = 0; i < count; i++) {
+ theTimer = NS_STATIC_CAST(nsTimerImpl*, mIdleTimers[i]);
+ NS_IF_RELEASE(theTimer);
+ }
+}
+
+NS_IMETHODIMP nsTimerManager::SetUseIdleTimers(PRBool aUseIdleTimers)
+{
+ if (aUseIdleTimers == PR_FALSE && gFireOnIdle == PR_TRUE)
+ return NS_ERROR_FAILURE;
+
+ gFireOnIdle = aUseIdleTimers;
+
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerManager::GetUseIdleTimers(PRBool *aUseIdleTimers)
+{
+ *aUseIdleTimers = gFireOnIdle;
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerManager::HasIdleTimers(PRBool *aHasTimers)
+{
+ nsAutoLock lock (mLock);
+ PRUint32 count = mIdleTimers.Count();
+ *aHasTimers = (count != 0);
+ return NS_OK;
+}
+
+nsresult nsTimerManager::AddIdleTimer(nsITimer* timer)
+{
+ if (!timer)
+ return NS_ERROR_FAILURE;
+ nsAutoLock lock(mLock);
+ mIdleTimers.AppendElement(timer);
+ NS_ADDREF(timer);
+ return NS_OK;
+}
+
+NS_IMETHODIMP nsTimerManager::FireNextIdleTimer()
+{
+ if (!gFireOnIdle || !nsIThread::IsMainThread()) {
+ return NS_OK;
+ }
+
+ nsTimerImpl *theTimer = nsnull;
+
+ {
+ nsAutoLock lock (mLock);
+ PRUint32 count = mIdleTimers.Count();
+
+ if (count == 0)
+ return NS_OK;
+
+ theTimer = NS_STATIC_CAST(nsTimerImpl*, mIdleTimers[0]);
+ mIdleTimers.RemoveElement(theTimer);
+ }
+
+ theTimer->Fire();
+
+ NS_RELEASE(theTimer);
+
+ return NS_OK;
+}
+
+
+// NOT FOR PUBLIC CONSUMPTION!
+nsresult
+NS_NewTimer(nsITimer* *aResult, nsTimerCallbackFunc aCallback, void *aClosure,
+ PRUint32 aDelay, PRUint32 aType)
+{
+ nsTimerImpl* timer = new nsTimerImpl();
+ if (timer == nsnull)
+ return NS_ERROR_OUT_OF_MEMORY;
+ NS_ADDREF(timer);
+
+ nsresult rv = timer->InitWithFuncCallback(aCallback, aClosure,
+ aDelay, aType);
+ if (NS_FAILED(rv)) {
+ NS_RELEASE(timer);
+ return rv;
+ }
+
+ *aResult = timer;
+ return NS_OK;
+}