// Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// (C) 2001, 2002 Ximian, Inc. http://www.ximian.com
-// Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
+// Copyright (C) 2004-2009 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
namespace System.Threading
{
-#if NET_2_0
[ComVisible (true)]
-#endif
public sealed class Timer : MarshalByRefObject, IDisposable
{
+ static Scheduler scheduler = Scheduler.Instance;
#region Timer instance fields
TimerCallback callback;
object state;
long due_time_ms;
long period_ms;
- long next_run; // in ticks
+ long next_run; // in ticks. Only 'Scheduler' can change it except for new timers without due time.
bool disposed;
#endregion
-
-#region Timer static fields
- static Thread scheduler;
- static Hashtable jobs;
- static AutoResetEvent change_event;
-#endregion
-
- /* we use a static initializer to avoid race issues with the thread creation */
- static Timer ()
- {
- change_event = new AutoResetEvent (false);
- jobs = new Hashtable ();
- scheduler = new Thread (SchedulerThread);
- scheduler.IsBackground = true;
- scheduler.Start ();
- }
-
- static long Ticks ()
- {
- return DateTime.GetTimeMonotonic ();
- }
-
- static private void SchedulerThread ()
- {
- Thread.CurrentThread.Name = "Timer-Scheduler";
- while (true) {
- long min_wait = long.MaxValue;
- lock (jobs) {
- ArrayList expired = null;
- long ticks = Ticks ();
- foreach (DictionaryEntry entry in jobs) {
- Timer t1 = entry.Value as Timer;
- if (t1.next_run <= ticks) {
- ThreadPool.QueueUserWorkItem (new WaitCallback (t1.callback), t1.state);
- if (t1.period_ms == -1 || ((t1.period_ms == 0 | t1.period_ms == Timeout.Infinite) && t1.due_time_ms != Timeout.Infinite)) {
- t1.next_run = long.MaxValue;
- if (expired == null)
- expired = new ArrayList ();
- expired.Add (t1);
- } else {
- t1.next_run = ticks + TimeSpan.TicksPerMillisecond * t1.period_ms;
- }
- }
- if (t1.next_run != long.MaxValue) {
- min_wait = Math.Min (min_wait, t1.next_run - ticks);
- }
- }
- if (expired != null) {
- int count = expired.Count;
- for (int i = 0; i < count; ++i) {
- jobs.Remove (expired [i]);
- }
- expired.Clear ();
- if (count > 50)
- expired = null;
- }
- }
- if (min_wait != long.MaxValue) {
- change_event.WaitOne ((int)(min_wait / TimeSpan.TicksPerMillisecond), true);
- } else {
- change_event.WaitOne (Timeout.Infinite, true);
- }
- }
- }
-
public Timer (TimerCallback callback, object state, int dueTime, int period)
{
- if (dueTime < -1)
- throw new ArgumentOutOfRangeException ("dueTime");
-
- if (period < -1)
- throw new ArgumentOutOfRangeException ("period");
-
Init (callback, state, dueTime, period);
}
public Timer (TimerCallback callback, object state, long dueTime, long period)
{
- if (dueTime < -1)
- throw new ArgumentOutOfRangeException ("dueTime");
-
- if (period < -1)
- throw new ArgumentOutOfRangeException ("period");
-
Init (callback, state, dueTime, period);
}
public Timer (TimerCallback callback, object state, TimeSpan dueTime, TimeSpan period)
- : this (callback, state, (long)dueTime.TotalMilliseconds, (long)period.TotalMilliseconds)
{
+ Init (callback, state, (long)dueTime.TotalMilliseconds, (long)period.TotalMilliseconds);
}
[CLSCompliant(false)]
public Timer (TimerCallback callback, object state, uint dueTime, uint period)
- : this (callback, state, (long) dueTime, (long) period)
{
+ // convert all values to long - with a special case for -1 / 0xffffffff
+ long d = (dueTime == UInt32.MaxValue) ? Timeout.Infinite : (long) dueTime;
+ long p = (period == UInt32.MaxValue) ? Timeout.Infinite : (long) period;
+ Init (callback, state, d, p);
}
-#if NET_2_0
public Timer (TimerCallback callback)
{
Init (callback, this, Timeout.Infinite, Timeout.Infinite);
}
-#endif
void Init (TimerCallback callback, object state, long dueTime, long period)
{
+ if (callback == null)
+ throw new ArgumentNullException ("callback");
+
this.callback = callback;
this.state = state;
- Change (dueTime, period);
+ Change (dueTime, period, true);
}
public bool Change (int dueTime, int period)
{
- return Change ((long)dueTime, (long)period);
+ return Change (dueTime, period, false);
+ }
+
+ public bool Change (TimeSpan dueTime, TimeSpan period)
+ {
+ return Change ((long)dueTime.TotalMilliseconds, (long)period.TotalMilliseconds, false);
+ }
+
+ [CLSCompliant(false)]
+ public bool Change (uint dueTime, uint period)
+ {
+ // convert all values to long - with a special case for -1 / 0xffffffff
+ long d = (dueTime == UInt32.MaxValue) ? Timeout.Infinite : (long) dueTime;
+ long p = (period == UInt32.MaxValue) ? Timeout.Infinite : (long) period;
+ return Change (d, p, false);
+ }
+
+ public void Dispose ()
+ {
+ if (disposed)
+ return;
+
+ disposed = true;
+ scheduler.Remove (this);
}
public bool Change (long dueTime, long period)
{
- if(dueTime > 4294967294)
- throw new NotSupportedException ("Due time too large");
+ return Change (dueTime, period, false);
+ }
+
+ const long MaxValue = UInt32.MaxValue - 1;
- if(period > 4294967294)
- throw new NotSupportedException ("Period too large");
+ bool Change (long dueTime, long period, bool first)
+ {
+ if (dueTime > MaxValue)
+ throw new ArgumentOutOfRangeException ("Due time too large");
- if (dueTime < -1)
+ if (period > MaxValue)
+ throw new ArgumentOutOfRangeException ("Period too large");
+
+ // Timeout.Infinite == -1, so this accept everything greater than -1
+ if (dueTime < Timeout.Infinite)
throw new ArgumentOutOfRangeException ("dueTime");
- if (period < -1)
+ if (period < Timeout.Infinite)
throw new ArgumentOutOfRangeException ("period");
if (disposed)
due_time_ms = dueTime;
period_ms = period;
+ long nr;
if (dueTime == 0) {
- next_run = Ticks ();
- } else if (dueTime == Timeout.Infinite) {
- next_run = long.MaxValue;
- } else {
- next_run = dueTime * TimeSpan.TicksPerMillisecond + Ticks ();
- }
- lock (jobs) {
- if (next_run != long.MaxValue) {
- Timer t = jobs [this] as Timer;
- if (t == null)
- jobs [this] = this;
- change_event.Set ();
- } else {
- jobs.Remove (this);
+ nr = 0; // Due now
+ } else if (dueTime < 0) { // Infinite == -1
+ nr = long.MaxValue;
+ /* No need to call Change () */
+ if (first) {
+ next_run = nr;
+ return true;
}
+ } else {
+ nr = dueTime * TimeSpan.TicksPerMillisecond + DateTime.GetTimeMonotonic ();
}
+
+ scheduler.Change (this, nr);
return true;
}
- public bool Change (TimeSpan dueTime, TimeSpan period)
+ public bool Dispose (WaitHandle notifyObject)
{
- return Change ((long)dueTime.TotalMilliseconds, (long)period.TotalMilliseconds);
+ if (notifyObject == null)
+ throw new ArgumentNullException ("notifyObject");
+ Dispose ();
+ NativeEventCalls.SetEvent_internal (notifyObject.Handle);
+ return true;
}
- [CLSCompliant(false)]
- public bool Change (uint dueTime, uint period)
- {
- if (dueTime > Int32.MaxValue)
- throw new NotSupportedException ("Due time too large");
+ sealed class TimerComparer : IComparer {
+ public int Compare (object x, object y)
+ {
+ Timer tx = (x as Timer);
+ if (tx == null)
+ return -1;
+ Timer ty = (y as Timer);
+ if (ty == null)
+ return 1;
+ long result = tx.next_run - ty.next_run;
+ if (result == 0)
+ return x == y ? 0 : -1;
+ return result > 0 ? 1 : -1;
+ }
+ }
- if (period > Int32.MaxValue)
- throw new NotSupportedException ("Period too large");
+ sealed class Scheduler {
+ static Scheduler instance;
+ SortedList list;
- return Change ((long) dueTime, (long) period);
- }
+ static Scheduler ()
+ {
+ instance = new Scheduler ();
+ }
- public void Dispose ()
- {
- disposed = true;
- lock (jobs) {
- jobs.Remove (this);
+ public static Scheduler Instance {
+ get { return instance; }
}
- }
- public bool Dispose (WaitHandle notifyObject)
- {
- Dispose ();
- NativeEventCalls.SetEvent_internal (notifyObject.Handle);
- return true;
- }
+ private Scheduler ()
+ {
+ list = new SortedList (new TimerComparer (), 1024);
+ Thread thread = new Thread (SchedulerThread);
+ thread.IsBackground = true;
+ thread.Start ();
+ }
+
+ public void Remove (Timer timer)
+ {
+ // We do not keep brand new items or those with no due time.
+ if (timer.next_run == 0 || timer.next_run == Int64.MaxValue)
+ return;
+
+ lock (this) {
+ // If this is the next item due (index = 0), the scheduler will wake up and find nothing.
+ // No need to Pulse ()
+ InternalRemove (timer);
+ }
+ }
+
+ public void Change (Timer timer, long new_next_run)
+ {
+ lock (this) {
+ InternalRemove (timer);
+ if (new_next_run == Int64.MaxValue) {
+ timer.next_run = new_next_run;
+ return;
+ }
+
+ if (!timer.disposed) {
+ // We should only change next_run after removing and before adding
+ timer.next_run = new_next_run;
+ Add (timer);
+ // If this timer is next in line, wake up the scheduler
+ if (list.GetByIndex (0) == timer)
+ Monitor.Pulse (this);
+ }
+ }
+ }
+
+ // This should be the only caller to list.Add!
+ void Add (Timer timer)
+ {
+ // Make sure there are no collisions (10000 ticks == 1ms, so we should be safe here)
+ int idx = list.IndexOfKey (timer);
+ if (idx != -1) {
+ bool up = (Int64.MaxValue - timer.next_run) > 20000 ? true : false;
+ while (true) {
+ idx++;
+ if (up)
+ timer.next_run++;
+ else
+ timer.next_run--;
+
+ if (idx >= list.Count)
+ break;
+ Timer t2 = (Timer) list.GetByIndex (idx);
+ if (t2.next_run != timer.next_run)
+ break;
+ }
+ }
+ list.Add (timer, timer);
+ //PrintList ();
+ }
+
+ int InternalRemove (Timer timer)
+ {
+ int idx = list.IndexOfKey (timer);
+ if (idx >= 0)
+ list.RemoveAt (idx);
+ return idx;
+ }
+ void SchedulerThread ()
+ {
+ Thread.CurrentThread.Name = "Timer-Scheduler";
+ ArrayList new_time = new ArrayList (512);
+ while (true) {
+ long ticks = DateTime.GetTimeMonotonic ();
+ lock (this) {
+ //PrintList ();
+ int i;
+ int count = list.Count;
+ for (i = 0; i < count; i++) {
+ Timer timer = (Timer) list.GetByIndex (i);
+ if (timer.next_run > ticks)
+ break;
+
+ list.RemoveAt (i);
+ count--;
+ i--;
+ ThreadPool.QueueUserWorkItem (new WaitCallback (timer.callback), timer.state);
+ long period = timer.period_ms;
+ long due_time = timer.due_time_ms;
+ bool no_more = (period == -1 || ((period == 0 || period == Timeout.Infinite) && due_time != Timeout.Infinite));
+ if (no_more) {
+ timer.next_run = Int64.MaxValue;
+ } else {
+ timer.next_run = DateTime.GetTimeMonotonic () + TimeSpan.TicksPerMillisecond * timer.period_ms;
+ new_time.Add (timer);
+ }
+ }
+
+ // Reschedule timers with a new due time
+ count = new_time.Count;
+ for (i = 0; i < count; i++) {
+ Timer timer = (Timer) new_time [i];
+ Add (timer);
+ }
+ new_time.Clear ();
+ ShrinkIfNeeded (new_time, 512);
+
+ // Shrink the list
+ int capacity = list.Capacity;
+ count = list.Count;
+ if (capacity > 1024 && count > 0 && (capacity / count) > 3)
+ list.Capacity = count * 2;
+
+ long min_next_run = Int64.MaxValue;
+ if (list.Count > 0)
+ min_next_run = ((Timer) list.GetByIndex (0)).next_run;
+
+ //PrintList ();
+ int ms_wait = -1;
+ if (min_next_run != Int64.MaxValue) {
+ long diff = min_next_run - DateTime.GetTimeMonotonic ();
+ ms_wait = (int)(diff / TimeSpan.TicksPerMillisecond);
+ if (ms_wait < 0)
+ ms_wait = 0;
+ }
+
+ // Wait until due time or a timer is changed and moves from/to the first place in the list.
+ Monitor.Wait (this, ms_wait);
+ }
+ }
+ }
+
+ void ShrinkIfNeeded (ArrayList list, int initial)
+ {
+ int capacity = list.Capacity;
+ int count = list.Count;
+ if (capacity > initial && count > 0 && (capacity / count) > 3)
+ list.Capacity = count * 2;
+ }
+
+ /*
+ void PrintList ()
+ {
+ Console.WriteLine ("BEGIN--");
+ for (int i = 0; i < list.Count; i++) {
+ Timer timer = (Timer) list.GetByIndex (i);
+ Console.WriteLine ("{0}: {1}", i, timer.next_run);
+ }
+ Console.WriteLine ("END----");
+ }
+ */
+ }
}
}
projects / mono.git / blobdiff