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;
+}