CancellationTokenSource.cs System::Threading::CancellationTokenSource System::Threading::CancellationTokenSource::CancellationTokenRegistrationEqualityComparer System System::Threading // //CancellationTokenSource.cs // //Authors: //Jérémie"Garuma"Laval<jeremie.laval@gmail.com> //MarekSafar(marek.safar@gmail.com) // //Copyright(c)2009Jérémie"Garuma"Laval //Copyright2011Xamarin,Inc(http://www.xamarin.com) // //Permissionisherebygranted,freeofcharge,toanypersonobtainingacopy //ofthissoftwareandassociateddocumentationfiles(the"Software"),todeal //intheSoftwarewithoutrestriction,includingwithoutlimitationtherights //touse,copy,modify,merge,publish,distribute,sublicense,and/orsell //copiesoftheSoftware,andtopermitpersonstowhomtheSoftwareis //furnishedtodoso,subjecttothefollowingconditions: // //Theabovecopyrightnoticeandthispermissionnoticeshallbeincludedin //allcopiesorsubstantialportionsoftheSoftware. // //THESOFTWAREISPROVIDED"ASIS",WITHOUTWARRANTYOFANYKIND,EXPRESSOR //IMPLIED,INCLUDINGBUTNOTLIMITEDTOTHEWARRANTIESOFMERCHANTABILITY, //FITNESSFORAPARTICULARPURPOSEANDNONINFRINGEMENT.INNOEVENTSHALLTHE //AUTHORSORCOPYRIGHTHOLDERSBELIABLEFORANYCLAIM,DAMAGESOROTHER //LIABILITY,WHETHERINANACTIONOFCONTRACT,TORTOROTHERWISE,ARISINGFROM, //OUTOFORINCONNECTIONWITHTHESOFTWAREORTHEUSEOROTHERDEALINGSIN //THESOFTWARE. #ifNET_4_0||UNITY_5_3_OR_NEWER usingSystem.Collections.Generic; usingSystem.Collections.Concurrent; namespaceSystem.Threading { #if!NET_4_5&&!UNITY_5_3_OR_NEWER sealed #endif publicclassCancellationTokenSource:IDisposable { boolcanceled; booldisposed; intcurrId=int.MinValue; ConcurrentDictionary<CancellationTokenRegistration, Action>callbacks; CancellationTokenRegistration[]linkedTokens; ManualResetEventhandle; internalstaticreadonlyCancellationTokenSourceNoneSource=newCancellationTokenSource(); internalstaticreadonlyCancellationTokenSourceCanceledSource=newCancellationTokenSource(); #ifNET_4_5||UNITY_5_3_OR_NEWER staticreadonlyTimerCallbacktimer_callback; Timertimer; #endif staticCancellationTokenSource() { CanceledSource.canceled=true; #ifNET_4_5||UNITY_5_3_OR_NEWER timer_callback=token=>{ varcts=(CancellationTokenSource)token; cts.Cancel(); }; #endif } //SpicyPixel:AOTFix.Dictionaryrequiresacomparer. classCancellationTokenRegistrationEqualityComparer:IEqualityComparer<CancellationTokenRegistration> { publicstaticreadonlyCancellationTokenRegistrationEqualityComparerDefault=newCancellationTokenRegistrationEqualityComparer(); publicboolEquals(CancellationTokenRegistrationx,CancellationTokenRegistrationy) { returnx.Equals(y); } publicintGetHashCode(CancellationTokenRegistrationobj) { returnobj.GetHashCode(); } } publicCancellationTokenSource() { callbacks=newConcurrentDictionary<CancellationTokenRegistration, Action>( CancellationTokenRegistrationEqualityComparer.Default); handle=newManualResetEvent(false); } #ifNET_4_5||UNITY_5_3_OR_NEWER publicCancellationTokenSource(intmillisecondsDelay) :this() { if(millisecondsDelay<-1) thrownewArgumentOutOfRangeException("millisecondsDelay"); if(millisecondsDelay!=Timeout.Infinite) timer=newTimer(timer_callback,this,millisecondsDelay,Timeout.Infinite); } publicCancellationTokenSource(TimeSpandelay) :this(CheckTimeout(delay)) { } #endif publicCancellationTokenToken{ get{ CheckDisposed(); returnnewCancellationToken(this); } } publicboolIsCancellationRequested{ get{ returncanceled; } } internalWaitHandleWaitHandle{ get{ CheckDisposed(); returnhandle; } } publicvoidCancel() { Cancel(false); } //Ifparameteristruewethrowexceptionassoonastheyappearotherwiseweaggregatethem publicvoidCancel(boolthrowOnFirstException) { CheckDisposed(); if(canceled) return; Thread.MemoryBarrier(); canceled=true; handle.Set(); if(linkedTokens!=null) UnregisterLinkedTokens(); List<Exception>exceptions=null; try{ Actioncb; for(intid=int.MinValue+1;id<=currId;id++){ if(!callbacks.TryRemove(newCancellationTokenRegistration(id,this),outcb)) continue; if(cb==null) continue; if(throwOnFirstException){ cb(); }else{ try{ cb(); }catch(Exceptione){ if(exceptions==null) exceptions=newList<Exception>(); exceptions.Add(e); } } } }finally{ callbacks.Clear(); } if(exceptions!=null) thrownewAggregateException(exceptions); } /*Thisisthecallbackregisteredonlinkedtokens *sothattheydon'tthrowanODEifthecallback *iscalledconcurrentlywithaDispose */ voidSafeLinkedCancel() { try{ Cancel(); }catch(ObjectDisposedException){} } #ifNET_4_5||UNITY_5_3_OR_NEWER publicvoidCancelAfter(TimeSpandelay) { CancelAfter(CheckTimeout(delay)); } publicvoidCancelAfter(intmillisecondsDelay) { if(millisecondsDelay<-1) thrownewArgumentOutOfRangeException("millisecondsDelay"); CheckDisposed(); if(canceled||millisecondsDelay==Timeout.Infinite) return; if(timer==null){ //Havetobecarefullnottocreatesecondarybackgroundtimer vart=newTimer(timer_callback,this,Timeout.Infinite,Timeout.Infinite); if(AotInterlocked.CompareExchange(reftimer,t,null)!=null) t.Dispose(); } timer.Change(millisecondsDelay,Timeout.Infinite); } #endif publicstaticCancellationTokenSourceCreateLinkedTokenSource(CancellationTokentoken1,CancellationTokentoken2) { returnCreateLinkedTokenSource(new[]{token1,token2}); } publicstaticCancellationTokenSourceCreateLinkedTokenSource(paramsCancellationToken[]tokens) { if(tokens==null) thrownewArgumentNullException("tokens"); if(tokens.Length==0) thrownewArgumentException("Emptytokensarray"); CancellationTokenSourcesrc=newCancellationTokenSource(); Actionaction=src.SafeLinkedCancel; varregistrations=newList<CancellationTokenRegistration>(tokens.Length); foreach(CancellationTokentokenintokens){ if(token.CanBeCanceled) registrations.Add(token.Register(action)); } src.linkedTokens=registrations.ToArray(); returnsrc; } staticintCheckTimeout(TimeSpandelay) { try{ returnchecked((int)delay.TotalMilliseconds); }catch(OverflowException){ thrownewArgumentOutOfRangeException("delay"); } } voidCheckDisposed() { if(disposed) thrownewObjectDisposedException(GetType().Name); } publicvoidDispose() { Dispose(true); } #ifNET_4_5||UNITY_5_3_OR_NEWER protectedvirtual #endif voidDispose(booldisposing) { if(disposing&&!disposed){ Thread.MemoryBarrier(); disposed=true; if(!canceled){ Thread.MemoryBarrier(); UnregisterLinkedTokens(); callbacks=null; } #ifNET_4_5||UNITY_5_3_OR_NEWER if(timer!=null) timer.Dispose(); #endif //SpicyPixel:Mustusethepublicinterface(e.g.Close) //handle.Dispose(); handle.Close(); } } voidUnregisterLinkedTokens() { varregistrations=AotInterlocked.Exchange(reflinkedTokens,null); if(registrations==null) return; foreach(varlinkedinregistrations) linked.Dispose(); } internalCancellationTokenRegistrationRegister(Actioncallback,booluseSynchronizationContext) { CheckDisposed(); vartokenReg=newCancellationTokenRegistration(Interlocked.Increment(refcurrId),this); /*Ifthesourceisalreadycanceledweexecutethecallbackimmediately *ifnot,wetrytoaddittothequeueandifitiscurrentlybeingprocessed *wetrytoexecuteitbackourselvestobesurethecallbackisran */ if(canceled) callback(); else{ callbacks.TryAdd(tokenReg,callback); if(canceled&&callbacks.TryRemove(tokenReg,outcallback)) callback(); } returntokenReg; } internalvoidRemoveCallback(CancellationTokenRegistrationreg) { //Ignorecallifthesourcehasbeendisposed if(disposed) return; Actiondummy; varcbs=callbacks; if(cbs!=null) cbs.TryRemove(reg,outdummy); } } } #endif