/mcs/class/corlib/System.Threading/Timer.cs
C# | 414 lines | 305 code | 50 blank | 59 comment | 79 complexity | 5aed467a738c2234be9f7cb63876fb17 MD5 | raw file
Possible License(s): Unlicense, Apache-2.0, LGPL-2.0, MPL-2.0-no-copyleft-exception, CC-BY-SA-3.0, GPL-2.0
- //
- // System.Threading.Timer.cs
- //
- // Authors:
- // Dick Porter (dick@ximian.com)
- // Gonzalo Paniagua Javier (gonzalo@ximian.com)
- //
- // (C) 2001, 2002 Ximian, Inc. http://www.ximian.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
- // "Software"), to deal in the Software without restriction, including
- // without limitation the rights to use, copy, modify, merge, publish,
- // distribute, sublicense, and/or sell copies of the Software, and to
- // permit persons to whom the Software is furnished to do so, subject to
- // the following conditions:
- //
- // The above copyright notice and this permission notice shall be
- // included in all copies or substantial portions of the Software.
- //
- // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
- // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- //
- using System.Runtime.InteropServices;
- using System.Collections.Generic;
- using System.Collections;
- namespace System.Threading
- {
- [ComVisible (true)]
- public sealed class Timer
- : MarshalByRefObject, IDisposable
- {
- static readonly Scheduler scheduler = Scheduler.Instance;
- #region Timer instance fields
- TimerCallback callback;
- object state;
- long due_time_ms;
- long period_ms;
- long next_run; // in ticks. Only 'Scheduler' can change it except for new timers without due time.
- bool disposed;
- #endregion
- public Timer (TimerCallback callback, object state, int dueTime, int period)
- {
- Init (callback, state, dueTime, period);
- }
- public Timer (TimerCallback callback, object state, long dueTime, long period)
- {
- Init (callback, state, dueTime, period);
- }
- public Timer (TimerCallback callback, object state, TimeSpan dueTime, TimeSpan period)
- {
- Init (callback, state, (long)dueTime.TotalMilliseconds, (long)period.TotalMilliseconds);
- }
- [CLSCompliant(false)]
- public Timer (TimerCallback callback, object state, 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;
- Init (callback, state, d, p);
- }
- public Timer (TimerCallback callback)
- {
- Init (callback, this, Timeout.Infinite, Timeout.Infinite);
- }
- 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, true);
- }
- public bool Change (int dueTime, int 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)
- {
- return Change (dueTime, period, false);
- }
- const long MaxValue = UInt32.MaxValue - 1;
- bool Change (long dueTime, long period, bool first)
- {
- if (dueTime > MaxValue)
- throw new ArgumentOutOfRangeException ("dueTime", "Due time too large");
- if (period > MaxValue)
- throw new ArgumentOutOfRangeException ("period", "Period too large");
- // Timeout.Infinite == -1, so this accept everything greater than -1
- if (dueTime < Timeout.Infinite)
- throw new ArgumentOutOfRangeException ("dueTime");
- if (period < Timeout.Infinite)
- throw new ArgumentOutOfRangeException ("period");
- if (disposed)
- return false;
- due_time_ms = dueTime;
- period_ms = period;
- long nr;
- if (dueTime == 0) {
- 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 Dispose (WaitHandle notifyObject)
- {
- if (notifyObject == null)
- throw new ArgumentNullException ("notifyObject");
- Dispose ();
- NativeEventCalls.SetEvent_internal (notifyObject.Handle);
- return true;
- }
- 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;
- }
- }
- sealed class Scheduler {
- static Scheduler instance;
- SortedList list;
- ManualResetEvent changed;
- static Scheduler ()
- {
- instance = new Scheduler ();
- }
- public static Scheduler Instance {
- get { return instance; }
- }
- private Scheduler ()
- {
- changed = new ManualResetEvent (false);
- 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)
- {
- bool wake = false;
- 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
- wake = (list.GetByIndex (0) == timer);
- }
- }
- if (wake)
- changed.Set ();
- }
- // lock held by caller
- int FindByDueTime (long nr)
- {
- int min = 0;
- int max = list.Count - 1;
- if (max < 0)
- return -1;
- if (max < 20) {
- while (min <= max) {
- Timer t = (Timer) list.GetByIndex (min);
- if (t.next_run == nr)
- return min;
- if (t.next_run > nr)
- return -1;
- min++;
- }
- return -1;
- }
- while (min <= max) {
- int half = min + ((max - min) >> 1);
- Timer t = (Timer) list.GetByIndex (half);
- if (nr == t.next_run)
- return half;
- if (nr > t.next_run)
- min = half + 1;
- else
- max = half - 1;
- }
- return -1;
- }
- // 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)
- // Do not use list.IndexOfKey here. See bug #648130
- int idx = FindByDueTime (timer.next_run);
- 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;
- }
- static WaitCallback TimerCaller = new WaitCallback (TimerCB);
- static void TimerCB (object o)
- {
- Timer timer = (Timer) o;
- try {
- timer.callback (timer.state);
- } catch {}
- }
- void SchedulerThread ()
- {
- Thread.CurrentThread.Name = "Timer-Scheduler";
- var new_time = new List<Timer> (512);
- while (true) {
- int ms_wait = -1;
- long ticks = DateTime.GetTimeMonotonic ();
- lock (this) {
- changed.Reset ();
- //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.UnsafeQueueUserWorkItem (TimerCaller, timer);
- 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 = 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 ();
- ms_wait = -1;
- if (min_next_run != Int64.MaxValue) {
- long diff = (min_next_run - DateTime.GetTimeMonotonic ()) / TimeSpan.TicksPerMillisecond;
- if (diff > Int32.MaxValue)
- ms_wait = Int32.MaxValue - 1;
- else {
- ms_wait = (int)(diff);
- 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.
- changed.WaitOne (ms_wait);
- }
- }
- void ShrinkIfNeeded (List<Timer> 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----");
- }
- */
- }
- }
- }