using System;
|
|
using System.Collections;
|
|
using System.Collections.Concurrent;
|
|
using System.Collections.Generic;
|
|
using System.Diagnostics;
|
|
using System.Linq;
|
|
using System.Text;
|
|
using System.Threading;
|
|
using System.Threading.Tasks;
|
|
|
|
namespace IPA.Utilities.Async
|
|
{
|
|
/// <summary>
|
|
/// A task scheduler that runs tasks on the Unity main thread via coroutines.
|
|
/// </summary>
|
|
public class UnityMainThreadTaskScheduler : TaskScheduler, IDisposable
|
|
{
|
|
/// <summary>
|
|
/// Gets the default main thread scheduler that is managed by BSIPA.
|
|
/// </summary>
|
|
/// <value>a scheduler that is managed by BSIPA</value>
|
|
public static new TaskScheduler Default { get; } = new UnityMainThreadTaskScheduler();
|
|
|
|
private readonly ConcurrentDictionary<QueueItem, Task> tasks = new ConcurrentDictionary<QueueItem, Task>();
|
|
private int queueEndPosition = 0;
|
|
private int queuePosition = 0;
|
|
|
|
private struct QueueItem : IEquatable<int>, IEquatable<Task>, IEquatable<QueueItem>
|
|
{
|
|
public int Index;
|
|
public Task Task;
|
|
|
|
public QueueItem(int index, Task task) : this()
|
|
{
|
|
Index = index;
|
|
Task = task;
|
|
}
|
|
|
|
public bool Equals(int other) => Index.Equals(other);
|
|
public bool Equals(Task other) => Task.Equals(other);
|
|
public bool Equals(QueueItem other) => other.Index == Index || other.Task == Task;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Gets whether or not this scheduler is currently executing tasks.
|
|
/// </summary>
|
|
/// <value><see langword="true"/> if the scheduler is running, <see langword="false"/> otherwise</value>
|
|
public bool IsRunning { get; private set; } = false;
|
|
|
|
/// <summary>
|
|
/// Gets whether or not this scheduler is in the process of shutting down.
|
|
/// </summary>
|
|
/// <value><see langword="true"/> if the scheduler is shutting down, <see langword="false"/> otherwise</value>
|
|
public bool Cancelling { get; private set; } = false;
|
|
|
|
private int yieldAfterTasks = 64;
|
|
/// <summary>
|
|
/// Gets or sets the number of tasks to execute before yielding back to Unity.
|
|
/// </summary>
|
|
/// <value>the number of tasks to execute per resume</value>
|
|
public int YieldAfterTasks
|
|
{
|
|
get => yieldAfterTasks;
|
|
set
|
|
{
|
|
ThrowIfDisposed();
|
|
if (value < 1)
|
|
throw new ArgumentException("Value cannot be less than 1", nameof(value));
|
|
yieldAfterTasks = value;
|
|
}
|
|
}
|
|
|
|
private TimeSpan yieldAfterTime = TimeSpan.FromMilliseconds(.5); // auto-yield if more than half a millis has passed by default
|
|
/// <summary>
|
|
/// Gets or sets the amount of time to execute tasks for before yielding back to Unity. Default is 0.5ms.
|
|
/// </summary>
|
|
/// <value>the amount of time to execute tasks for before yielding back to Unity</value>
|
|
public TimeSpan YieldAfterTime
|
|
{
|
|
get => yieldAfterTime;
|
|
set
|
|
{
|
|
ThrowIfDisposed();
|
|
if (value <= TimeSpan.Zero)
|
|
throw new ArgumentException("Value must be greater than zero", nameof(value));
|
|
yieldAfterTime = value;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// When used as a Unity coroutine, runs the scheduler. Otherwise, this is an invalid call.
|
|
/// </summary>
|
|
/// <returns>a Unity coroutine</returns>
|
|
/// <exception cref="ObjectDisposedException">if this scheduler is disposed</exception>
|
|
/// <exception cref="InvalidOperationException">if the scheduler is already running</exception>
|
|
public IEnumerator Coroutine()
|
|
{
|
|
ThrowIfDisposed();
|
|
|
|
if (IsRunning)
|
|
throw new InvalidOperationException("Scheduler already running");
|
|
|
|
Cancelling = false;
|
|
IsRunning = true;
|
|
yield return null; // yield immediately
|
|
|
|
var sw = new Stopwatch();
|
|
|
|
try
|
|
{
|
|
while (!Cancelling)
|
|
{
|
|
if (queuePosition < queueEndPosition)
|
|
{
|
|
var yieldAfter = YieldAfterTasks;
|
|
sw.Start();
|
|
for (int i = 0; i < yieldAfter && queuePosition < queueEndPosition
|
|
&& sw.Elapsed < YieldAfterTime; i++)
|
|
{
|
|
if (tasks.TryRemove(new QueueItem { Index = Interlocked.Increment(ref queuePosition) }, out var task))
|
|
TryExecuteTask(task); // we succesfully removed the task
|
|
else
|
|
i++; // we didn't
|
|
}
|
|
sw.Reset();
|
|
}
|
|
yield return null;
|
|
}
|
|
}
|
|
finally
|
|
{
|
|
sw.Reset();
|
|
IsRunning = false;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Cancels the scheduler. If the scheduler is currently executing tasks, that batch will finish first.
|
|
/// All remaining tasks will be left in the queue.
|
|
/// </summary>
|
|
/// <exception cref="ObjectDisposedException">if this scheduler is disposed</exception>
|
|
/// <exception cref="InvalidOperationException">if the scheduler is not running</exception>
|
|
public void Cancel()
|
|
{
|
|
ThrowIfDisposed();
|
|
|
|
if (!IsRunning) throw new InvalidOperationException("The scheduler is not running");
|
|
Cancelling = true;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Throws a <see cref="NotSupportedException"/>.
|
|
/// </summary>
|
|
/// <returns>nothing</returns>
|
|
/// <exception cref="NotSupportedException">Always.</exception>
|
|
protected override IEnumerable<Task> GetScheduledTasks()
|
|
{
|
|
// this is only for debuggers which we can't use sooooo
|
|
throw new NotSupportedException();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Queues a given <see cref="Task"/> to this scheduler. The <see cref="Task"/> <i>must></i> be
|
|
/// scheduled for this <see cref="TaskScheduler"/> by the runtime.
|
|
/// </summary>
|
|
/// <param name="task">the <see cref="Task"/> to queue</param>
|
|
/// <exception cref="ObjectDisposedException">Thrown if this object has already been disposed.</exception>
|
|
protected override void QueueTask(Task task)
|
|
{
|
|
ThrowIfDisposed();
|
|
|
|
tasks.TryAdd(new QueueItem(Interlocked.Increment(ref queueEndPosition), task), task);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Rejects any attempts to execute a task inline.
|
|
/// </summary>
|
|
/// <remarks>
|
|
/// This task scheduler <i>always</i> runs its tasks on the thread that it manages, therefore it doesn't
|
|
/// make sense to run it inline.
|
|
/// </remarks>
|
|
/// <param name="task">the task to attempt to execute</param>
|
|
/// <param name="taskWasPreviouslyQueued">whether the task was previously queued to this scheduler</param>
|
|
/// <returns><see langword="false"/></returns>
|
|
/// <exception cref="ObjectDisposedException">Thrown if this object has already been disposed.</exception>
|
|
protected override bool TryExecuteTaskInline(Task task, bool taskWasPreviouslyQueued)
|
|
{
|
|
ThrowIfDisposed();
|
|
|
|
if (!UnityGame.OnMainThread) return false;
|
|
|
|
if (taskWasPreviouslyQueued)
|
|
if (!tasks.TryRemove(new QueueItem { Task = task }, out var _))
|
|
return false; // if we couldn't remove it, its not in our queue, so it already ran
|
|
|
|
return TryExecuteTask(task);
|
|
}
|
|
|
|
private void ThrowIfDisposed()
|
|
{
|
|
if (disposedValue)
|
|
throw new ObjectDisposedException(nameof(SingleThreadTaskScheduler));
|
|
}
|
|
|
|
#region IDisposable Support
|
|
private bool disposedValue = false; // To detect redundant calls
|
|
|
|
protected virtual void Dispose(bool disposing)
|
|
{
|
|
if (!disposedValue)
|
|
{
|
|
if (disposing)
|
|
{
|
|
|
|
}
|
|
|
|
disposedValue = true;
|
|
}
|
|
}
|
|
|
|
// This code added to correctly implement the disposable pattern.
|
|
public void Dispose()
|
|
{
|
|
// Do not change this code. Put cleanup code in Dispose(bool disposing) above.
|
|
Dispose(true);
|
|
}
|
|
#endregion
|
|
}
|
|
}
|