baseline: OpenMU upstream b5a0961 (fresh source)

src/GameLogic/AsyncDisposable.cs

@@ -0,0 +1,54 @@
+// <copyright file="AsyncDisposable.cs" company="MUnique">
+// Licensed under the MIT License. See LICENSE file in the project root for full license information.
+// </copyright>
+
+namespace MUnique.OpenMU.GameLogic;
+
+/// <summary>
+/// Base class for classes which want to implement <see cref="IAsyncDisposable"/>.
+/// </summary>
+public class AsyncDisposable : Disposable, IAsyncDisposable
+{
+    private bool _isDisposing;
+
+    /// <summary>
+    /// Gets a value indicating whether this instance is disposing.
+    /// </summary>
+    /// <value>
+    ///   <c>true</c> if this instance is disposing; otherwise, <c>false</c>.
+    /// </value>
+    public new bool IsDisposing
+    {
+        get => this._isDisposing || base.IsDisposing;
+        private set => this._isDisposing = value;
+    }
+
+    /// <inheritdoc />
+    public async ValueTask DisposeAsync()
+    {
+        if (!this.IsDisposed && !this.IsDisposing)
+        {
+            this.IsDisposing = true;
+            try
+            {
+                await this.DisposeAsyncCore().ConfigureAwait(false);
+                this.Dispose(true);
+                GC.SuppressFinalize(this);
+            }
+            finally
+            {
+                this.IsDisposing = false;
+            }
+        }
+    }
+
+    /// <summary>
+    /// Performs application-defined tasks associated with freeing, releasing, or
+    /// resetting unmanaged resources asynchronously.
+    /// </summary>
+    [System.Diagnostics.CodeAnalysis.SuppressMessage("Style", "VSTHRD200:Use \"Async\" suffix for async methods", Justification = "This naming is suggested by microsoft itself.")]
+    protected virtual ValueTask DisposeAsyncCore()
+    {
+        return ValueTask.CompletedTask;
+    }
+}