osu/osu.Game/Utils/TaskChain.cs

45 lines
1.8 KiB
C#

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.
using System;
using System.Threading;
using System.Threading.Tasks;
using osu.Game.Extensions;
namespace osu.Game.Utils
{
/// <summary>
/// A chain of <see cref="Task"/>s that run sequentially.
/// </summary>
public class TaskChain
{
private readonly object taskLock = new object();
private Task lastTaskInChain = Task.CompletedTask;
/// <summary>
/// Adds a new task to the end of this <see cref="TaskChain"/>.
/// </summary>
/// <param name="action">The action to be executed.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> for this task. Does not affect further tasks in the chain.</param>
/// <returns>The awaitable <see cref="Task"/>.</returns>
public Task Add(Action action, CancellationToken cancellationToken = default)
{
lock (taskLock)
return lastTaskInChain = lastTaskInChain.ContinueWithSequential(action, cancellationToken);
}
/// <summary>
/// Adds a new task to the end of this <see cref="TaskChain"/>.
/// </summary>
/// <param name="task">The task to be executed.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> for this task. Does not affect further tasks in the chain.</param>
/// <returns>The awaitable <see cref="Task"/>.</returns>
public Task Add(Func<Task> task, CancellationToken cancellationToken = default)
{
lock (taskLock)
return lastTaskInChain = lastTaskInChain.ContinueWithSequential(task, cancellationToken);
}
}
}