TaskCompletionQueue.cs System::Threading::Tasks::TaskCompletionQueue System System::Threading System::Threading::Tasks // //TaskCompletionQueue.cs // //Authors: //JérémieLaval<jeremiedotlavalatxamarindotcom> // //Copyright2011XamarinInc(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; usingSystem.Threading; usingSystem.Collections.Generic; usingSystem.Collections.Concurrent; namespaceSystem.Threading.Tasks { internalstructTaskCompletionQueue<TCompletion>whereTCompletion:class { TCompletionsingle; ConcurrentOrderedList<TCompletion>completed; publicvoidAdd(TCompletioncontinuation) { if(single==null&&AotInterlocked.CompareExchange(refsingle,continuation,null)==null) return; if(completed==null) AotInterlocked.CompareExchange(refcompleted,newConcurrentOrderedList<TCompletion>(),null); completed.TryAdd(continuation); } publicboolRemove(TCompletioncontinuation) { TCompletiontemp=single; if(temp!=null&&temp==continuation&&AotInterlocked.CompareExchange(refsingle,null,continuation)==continuation) returntrue; if(completed!=null) returncompleted.TryRemove(continuation); returnfalse; } publicboolHasElements{ get{ returnsingle!=null||(completed!=null&&completed.Count!=0); } } publicboolTryGetNextCompletion(outTCompletioncontinuation) { continuation=null; if(single!=null&&(continuation=AotInterlocked.Exchange(refsingle,null))!=null) returntrue; returncompleted!=null&&completed.TryPop(outcontinuation); } } } #endif