Release v40.0

app/Desktop/Arguments.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using DHT.Utils.Logging;
 
 namespace DHT.Desktop;
@@ -15,8 +16,8 @@ sealed class Arguments {
 	public ushort? ServerPort { get; }
 	public string? ServerToken { get; }
 
-	public Arguments(string[] args) {
-		for (int i = FirstArgument; i < args.Length; i++) {
+	public Arguments(IReadOnlyList<string> args) {
+		for (int i = FirstArgument; i < args.Count; i++) {
 			string key = args[i];
 
 			switch (key) {
@@ -35,7 +36,7 @@ sealed class Arguments {
 				value = key;
 				key = "-db";
 			}
-			else if (i >= args.Length - 1) {
+			else if (i >= args.Count - 1) {
 				Log.Warn("Missing value for command line argument: " + key);
 				continue;
 			}

app/Desktop/Common/BytesValueConverter.cs

@@ -19,13 +19,13 @@ sealed class BytesValueConverter : IValueConverter {
 		}
 	}
 
-	private static readonly Unit[] Units = {
-		new ("B", decimalPlaces: 0),
-		new ("kB", decimalPlaces: 0),
-		new ("MB", decimalPlaces: 1),
-		new ("GB", decimalPlaces: 1),
-		new ("TB", decimalPlaces: 1)
-	};
+	private static readonly Unit[] Units = [
+		new Unit("B", decimalPlaces: 0),
+		new Unit("kB", decimalPlaces: 0),
+		new Unit("MB", decimalPlaces: 1),
+		new Unit("GB", decimalPlaces: 1),
+		new Unit("TB", decimalPlaces: 1)
+	];
 
 	private const int Scale = 1000;
 

app/Desktop/Dialogs/CheckBox/CheckBoxDialogModel.cs

@@ -59,7 +59,7 @@ class CheckBoxDialogModel : ObservableObject {
 }
 
 sealed class CheckBoxDialogModel<T> : CheckBoxDialogModel {
-	public new IReadOnlyList<CheckBoxItem<T>> Items { get; }
+	private new IReadOnlyList<CheckBoxItem<T>> Items { get; }
 
 	public IEnumerable<CheckBoxItem<T>> SelectedItems => Items.Where(static item => item.IsChecked);
 

app/Desktop/Dialogs/TextBox/TextBoxDialogModel.cs

@@ -36,7 +36,7 @@ class TextBoxDialogModel : ObservableObject {
 }
 
 sealed class TextBoxDialogModel<T> : TextBoxDialogModel {
-	public new IReadOnlyList<TextBoxItem<T>> Items { get; }
+	private new IReadOnlyList<TextBoxItem<T>> Items { get; }
 
 	public IEnumerable<TextBoxItem<T>> ValidItems => Items.Where(static item => item.IsValid);
 

app/Desktop/Discord/DiscordAppSettings.cs

@@ -39,7 +39,7 @@ static class DiscordAppSettings {
 
 	public static async Task<bool?> AreDevToolsEnabled() {
 		try {
-			var settingsJson = await ReadSettingsJson().ConfigureAwait(false);
+			var settingsJson = await ReadSettingsJson();
 			return AreDevToolsEnabled(settingsJson);
 		} catch (Exception e) {
 			Log.Error("Cannot read settings file.");

app/Desktop/Discord/DiscordAppSettingsJsonContext.cs

@@ -5,4 +5,4 @@ namespace DHT.Desktop.Discord;
 
 [JsonSourceGenerationOptions(GenerationMode = JsonSourceGenerationMode.Default, WriteIndented = true)]
 [JsonSerializable(typeof(JsonObject))]
-sealed partial class DiscordAppSettingsJsonContext : JsonSerializerContext {}
+sealed partial class DiscordAppSettingsJsonContext : JsonSerializerContext;

app/Desktop/Main/Pages/DatabasePageModel.cs

@@ -92,7 +92,7 @@ sealed class DatabasePageModel {
 				await target.AddFrom(db);
 				return true;
 			} finally {
-				db.Dispose();
+				await db.DisposeAsync();
 			}
 		});
 	}

app/Desktop/Main/Pages/DebugPageModel.cs

@@ -128,7 +128,7 @@ namespace DHT.Desktop.Main.Pages {
 			return options[(int) Math.Floor(options.Length * rand.NextDouble() * rand.NextDouble())];
 		}
 
-		private static readonly string[] RandomWords = {
+		private static readonly string[] RandomWords = [
 			"apple", "apricot", "artichoke", "arugula", "asparagus", "avocado",
 			"banana", "bean", "beechnut", "beet", "blackberry", "blackcurrant", "blueberry", "boysenberry", "bramble", "broccoli",
 			"cabbage", "cacao", "cantaloupe", "caper", "carambola", "carrot", "cauliflower", "celery", "chard", "cherry", "chokeberry", "citron", "clementine", "coconut", "corn", "crabapple", "cranberry", "cucumber", "currant",
@@ -151,8 +151,8 @@ namespace DHT.Desktop.Main.Pages {
 			"vanilla",
 			"watercress", "watermelon",
 			"yam",
-			"zucchini",
-		};
+			"zucchini"
+		];
 
 		private static string RandomText(Random rand, int maxWords) {
 			int wordCount = 1 + (int) Math.Floor(maxWords * Math.Pow(rand.NextDouble(), 3));

app/Desktop/Main/Pages/TrackingPageModel.cs

@@ -78,7 +78,7 @@ sealed partial class TrackingPageModel : ObservableObject {
 	}
 
 	private async Task InitializeDevToolsToggle() {
-		bool? devToolsEnabled = await DiscordAppSettings.AreDevToolsEnabled();
+		bool? devToolsEnabled = await Task.Run(DiscordAppSettings.AreDevToolsEnabled);
 
 		if (devToolsEnabled.HasValue) {
 			AreDevToolsEnabled = devToolsEnabled.Value;

app/Desktop/Main/Pages/ViewerPageModel.cs

@@ -65,10 +65,13 @@ sealed partial class ViewerPageModel : ObservableObject, IDisposable {
 			var fullPath = await PrepareTemporaryViewerFile();
 			var strategy = new LiveViewerExportStrategy(ServerConfiguration.Port, ServerConfiguration.Token);
 
-			await WriteViewerFile(fullPath, strategy);
-			Process.Start(new ProcessStartInfo(fullPath) { UseShellExecute = true });
+			await ProgressDialog.ShowIndeterminate(window, "Open Viewer", "Creating viewer...", _ => Task.Run(() => WriteViewerFile(fullPath, strategy)));
+			
+			Process.Start(new ProcessStartInfo(fullPath) {
+				UseShellExecute = true
+			});
 		} catch (Exception e) {
-			await Dialog.ShowOk(window, "Open Viewer", "Could not save viewer: " + e.Message);
+			await Dialog.ShowOk(window, "Open Viewer", "Could not create or save viewer: " + e.Message);
 		}
 	}
 
@@ -106,9 +109,9 @@ sealed partial class ViewerPageModel : ObservableObject, IDisposable {
 		}
 
 		try {
-			await WriteViewerFile(path, StandaloneViewerExportStrategy.Instance);
+			await ProgressDialog.ShowIndeterminate(window, "Save Viewer", "Creating viewer...", _ => Task.Run(() => WriteViewerFile(path, StandaloneViewerExportStrategy.Instance)));
 		} catch (Exception e) {
-			await Dialog.ShowOk(window, "Save Viewer", "Could not save viewer: " + e.Message);
+			await Dialog.ShowOk(window, "Save Viewer", "Could not create or save viewer: " + e.Message);
 		}
 	}
 

app/Server/Database/DummyDatabaseFile.cs

@@ -23,5 +23,7 @@ sealed class DummyDatabaseFile : IDatabaseFile {
 		return Task.CompletedTask;
 	}
 
-	public void Dispose() {}
+	public ValueTask DisposeAsync() {
+		return ValueTask.CompletedTask;
+	}
 }

app/Server/Database/Export/ViewerJsonContext.cs

@@ -3,9 +3,9 @@ using System.Text.Json.Serialization;
 namespace DHT.Server.Database.Export;
 
 [JsonSourceGenerationOptions(
-	Converters = new [] { typeof(SnowflakeJsonSerializer) },
+	Converters = [typeof(SnowflakeJsonSerializer)],
 	PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
 	GenerationMode = JsonSourceGenerationMode.Default
 )]
 [JsonSerializable(typeof(ViewerJson))]
-sealed partial class ViewerJsonContext : JsonSerializerContext {}
+sealed partial class ViewerJsonContext : JsonSerializerContext;

app/Server/Database/IDatabaseFile.cs

@@ -4,7 +4,7 @@ using DHT.Server.Database.Repositories;
 
 namespace DHT.Server.Database;
 
-public interface IDatabaseFile : IDisposable {
+public interface IDatabaseFile : IAsyncDisposable {
 	string Path { get; }
 
 	IUserRepository Users { get; }

app/Server/Database/Import/DiscordEmbedLegacyJsonContext.cs

@@ -4,4 +4,4 @@ namespace DHT.Server.Database.Import;
 
 [JsonSourceGenerationOptions(PropertyNamingPolicy = JsonKnownNamingPolicy.SnakeCaseLower, GenerationMode = JsonSourceGenerationMode.Default)]
 [JsonSerializable(typeof(DiscordEmbedLegacyJson))]
-sealed partial class DiscordEmbedLegacyJsonContext : JsonSerializerContext {}
+sealed partial class DiscordEmbedLegacyJsonContext : JsonSerializerContext;

app/Server/Database/Sqlite/Repositories/SqliteAttachmentRepository.cs

@@ -22,7 +22,7 @@ sealed class SqliteAttachmentRepository : BaseSqliteRepository, IAttachmentRepos
 	}
 
 	public async Task<long> Count(AttachmentFilter? filter, CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		return await conn.ExecuteReaderAsync("SELECT COUNT(DISTINCT normalized_url) FROM attachments a" + filter.GenerateWhereClause("a"), static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 }

app/Server/Database/Sqlite/Repositories/SqliteChannelRepository.cs

@@ -16,7 +16,7 @@ sealed class SqliteChannelRepository : BaseSqliteRepository, IChannelRepository
 	}
 
 	public async Task Add(IReadOnlyList<Channel> channels) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using (var tx = await conn.BeginTransactionAsync()) {
 			await using var cmd = conn.Upsert("channels", [
@@ -47,12 +47,12 @@ sealed class SqliteChannelRepository : BaseSqliteRepository, IChannelRepository
 	}
 
 	public override async Task<long> Count(CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM channels", static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
 	public async IAsyncEnumerable<Channel> Get() {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command("SELECT id, server, name, parent_id, position, topic, nsfw FROM channels");
 		await using var reader = await cmd.ExecuteReaderAsync();

app/Server/Database/Sqlite/Repositories/SqliteDownloadRepository.cs

@@ -21,7 +21,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	}
 
 	public async Task AddDownload(Data.Download download) {
-		using (var conn = pool.Take()) {
+		await using (var conn = await pool.Take()) {
 			await using var cmd = conn.Upsert("downloads", [
 				("normalized_url", SqliteType.Text),
 				("download_url", SqliteType.Text),
@@ -42,7 +42,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	}
 
 	public override async Task<long> Count(CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM downloads", static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
@@ -97,14 +97,14 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 
 		var result = new DownloadStatusStatistics();
 
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		await LoadUndownloadedStatistics(conn, result, cancellationToken);
 		await LoadSuccessStatistics(conn, result, cancellationToken);
 		return result;
 	}
 
 	public async IAsyncEnumerable<Data.Download> GetWithoutData() {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command("SELECT normalized_url, download_url, status, size FROM downloads");
 		await using var reader = await cmd.ExecuteReaderAsync();
@@ -120,7 +120,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	}
 
 	public async Task<Data.Download> HydrateWithData(Data.Download download) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command("SELECT blob FROM downloads WHERE normalized_url = :url");
 		cmd.AddAndSet(":url", SqliteType.Text, download.NormalizedUrl);
@@ -136,7 +136,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	}
 
 	public async Task<DownloadedAttachment?> GetDownloadedAttachment(string normalizedUrl) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command(
 			"""
@@ -162,7 +162,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	}
 
 	public async Task<int> EnqueueDownloadItems(AttachmentFilter? filter, CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command(
 			$"""
@@ -181,7 +181,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	public async IAsyncEnumerable<DownloadItem> PullEnqueuedDownloadItems(int count, [EnumeratorCancellation] CancellationToken cancellationToken) {
 		var found = new List<DownloadItem>();
 
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using (var cmd = conn.Command("SELECT normalized_url, download_url, size FROM downloads WHERE status = :enqueued LIMIT :limit")) {
 			cmd.AddAndSet(":enqueued", SqliteType.Integer, (int) DownloadStatus.Enqueued);
@@ -215,7 +215,7 @@ sealed class SqliteDownloadRepository : BaseSqliteRepository, IDownloadRepositor
 	}
 
 	public async Task RemoveDownloadItems(DownloadItemFilter? filter, FilterRemovalMode mode) {
-		using (var conn = pool.Take()) {
+		await using (var conn = await pool.Take()) {
 			await conn.ExecuteAsync(
 				$"""
 				 -- noinspection SqlWithoutWhere

app/Server/Database/Sqlite/Repositories/SqliteMessageRepository.cs

@@ -36,7 +36,7 @@ sealed class SqliteMessageRepository : BaseSqliteRepository, IMessageRepository
 
 		bool addedAttachments = false;
 
-		using (var conn = pool.Take()) {
+		await using (var conn = await pool.Take()) {
 			await using var tx = await conn.BeginTransactionAsync();
 
 			await using var messageCmd = conn.Upsert("messages", [
@@ -170,7 +170,7 @@ sealed class SqliteMessageRepository : BaseSqliteRepository, IMessageRepository
 	}
 	
 	public async Task<long> Count(MessageFilter? filter, CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM messages" + filter.GenerateWhereClause(), static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
@@ -205,7 +205,7 @@ sealed class SqliteMessageRepository : BaseSqliteRepository, IMessageRepository
 	}
 
 	public async IAsyncEnumerable<Message> Get(MessageFilter? filter) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		const string AttachmentSql =
 			"""
@@ -281,7 +281,7 @@ sealed class SqliteMessageRepository : BaseSqliteRepository, IMessageRepository
 	}
 
 	public async IAsyncEnumerable<ulong> GetIds(MessageFilter? filter) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		
 		await using var cmd = conn.Command("SELECT message_id FROM messages" + filter.GenerateWhereClause());
 		await using var reader = await cmd.ExecuteReaderAsync();
@@ -292,7 +292,7 @@ sealed class SqliteMessageRepository : BaseSqliteRepository, IMessageRepository
 	}
 
 	public async Task Remove(MessageFilter filter, FilterRemovalMode mode) {
-		using (var conn = pool.Take()) {
+		await using (var conn = await pool.Take()) {
 			await conn.ExecuteAsync(
 				$"""
 				 -- noinspection SqlWithoutWhere

app/Server/Database/Sqlite/Repositories/SqliteServerRepository.cs

@@ -16,7 +16,7 @@ sealed class SqliteServerRepository : BaseSqliteRepository, IServerRepository {
 	}
 
 	public async Task Add(IReadOnlyList<Data.Server> servers) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using (var tx = await conn.BeginTransactionAsync()) {
 			await using var cmd = conn.Upsert("servers", [
@@ -39,12 +39,12 @@ sealed class SqliteServerRepository : BaseSqliteRepository, IServerRepository {
 	}
 
 	public override async Task<long> Count(CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM servers", static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
 	public async IAsyncEnumerable<Data.Server> Get() {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 
 		await using var cmd = conn.Command("SELECT id, name, type FROM servers");
 		await using var reader = await cmd.ExecuteReaderAsync();

app/Server/Database/Sqlite/Repositories/SqliteUserRepository.cs

@@ -16,7 +16,7 @@ sealed class SqliteUserRepository : BaseSqliteRepository, IUserRepository {
 	}
 	
 	public async Task Add(IReadOnlyList<User> users) {
-		using (var conn = pool.Take()) {
+		await using (var conn = await pool.Take()) {
 			await using var tx = await conn.BeginTransactionAsync();
 			
 			await using var cmd = conn.Upsert("users", [
@@ -41,12 +41,12 @@ sealed class SqliteUserRepository : BaseSqliteRepository, IUserRepository {
 	}
 
 	public override async Task<long> Count(CancellationToken cancellationToken) {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		return await conn.ExecuteReaderAsync("SELECT COUNT(*) FROM users", static reader => reader?.GetInt64(0) ?? 0L, cancellationToken);
 	}
 
 	public async IAsyncEnumerable<User> Get() {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		
 		await using var cmd = conn.Command("SELECT id, name, avatar_url, discriminator FROM users");
 		await using var reader = await cmd.ExecuteReaderAsync();

app/Server/Database/Sqlite/SqliteDatabaseFile.cs

@@ -16,14 +16,14 @@ public sealed class SqliteDatabaseFile : IDatabaseFile {
 			Mode = SqliteOpenMode.ReadWriteCreate,
 		};
 
-		var pool = new SqliteConnectionPool(connectionString, DefaultPoolSize);
+		var pool = await SqliteConnectionPool.Create(connectionString, DefaultPoolSize);
 		bool wasOpened;
 
 		try {
-			using var conn = pool.Take();
+			await using var conn = await pool.Take();
 			wasOpened = await new Schema(conn).Setup(schemaUpgradeCallbacks);
 		} catch (Exception) {
-			pool.Dispose();
+			await pool.DisposeAsync();
 			throw;
 		}
 
@@ -31,7 +31,7 @@ public sealed class SqliteDatabaseFile : IDatabaseFile {
 			return new SqliteDatabaseFile(path, pool);
 		}
 		else {
-			pool.Dispose();
+			await pool.DisposeAsync();
 			return null;
 		}
 	}
@@ -65,18 +65,18 @@ public sealed class SqliteDatabaseFile : IDatabaseFile {
 		downloads = new SqliteDownloadRepository(pool);
 	}
 
-	public void Dispose() {
+	public async ValueTask DisposeAsync() {
 		users.Dispose();
 		servers.Dispose();
 		channels.Dispose();
 		messages.Dispose();
 		attachments.Dispose();
 		downloads.Dispose();
-		pool.Dispose();
+		await pool.DisposeAsync();
 	}
 
 	public async Task Vacuum() {
-		using var conn = pool.Take();
+		await using var conn = await pool.Take();
 		await conn.ExecuteAsync("VACUUM");
 	}
 }

app/Server/Database/Sqlite/Utils/ISqliteConnection.cs

@@ -3,6 +3,6 @@ using Microsoft.Data.Sqlite;
 
 namespace DHT.Server.Database.Sqlite.Utils;
 
-interface ISqliteConnection : IDisposable {
+interface ISqliteConnection : IAsyncDisposable {
 	SqliteConnection InnerConnection { get; }
 }

app/Server/Database/Sqlite/Utils/SqliteConnectionPool.cs

@@ -1,100 +1,77 @@
 using System;
-using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Threading;
-using DHT.Utils.Logging;
+using System.Threading.Tasks;
+using DHT.Utils.Collections;
 using Microsoft.Data.Sqlite;
 
 namespace DHT.Server.Database.Sqlite.Utils;
 
-sealed class SqliteConnectionPool : IDisposable {
+sealed class SqliteConnectionPool : IAsyncDisposable {
+	public static async Task<SqliteConnectionPool> Create(SqliteConnectionStringBuilder connectionStringBuilder, int poolSize) {
+		var pool = new SqliteConnectionPool(poolSize);
+		await pool.InitializePooledConnections(connectionStringBuilder);
+		return pool;
+	}
+
 	private static string GetConnectionString(SqliteConnectionStringBuilder connectionStringBuilder) {
 		connectionStringBuilder.Pooling = false;
 		return connectionStringBuilder.ToString();
 	}
 
-	private readonly object monitor = new ();
-	private readonly Random rand = new ();
-	private volatile bool isDisposed;
+	private readonly int poolSize;
+	private readonly List<PooledConnection> all;
+	private readonly ConcurrentPool<PooledConnection> free;
 
-	private readonly BlockingCollection<PooledConnection> free = new (new ConcurrentStack<PooledConnection>());
-	private readonly List<PooledConnection> used;
+	private readonly CancellationTokenSource disposalTokenSource = new ();
+	private readonly CancellationToken disposalToken;
 
-	public SqliteConnectionPool(SqliteConnectionStringBuilder connectionStringBuilder, int poolSize) {
+	private SqliteConnectionPool(int poolSize) {
+		this.poolSize = poolSize;
+		this.all = new List<PooledConnection>(poolSize);
+		this.free = new ConcurrentPool<PooledConnection>(poolSize);
+		this.disposalToken = disposalTokenSource.Token;
+	}
+
+	private async Task InitializePooledConnections(SqliteConnectionStringBuilder connectionStringBuilder) {
 		var connectionString = GetConnectionString(connectionStringBuilder);
 
 		for (int i = 0; i < poolSize; i++) {
 			var conn = new SqliteConnection(connectionString);
 			conn.Open();
 
-			var pooledConn = new PooledConnection(this, conn);
+			var pooledConnection = new PooledConnection(this, conn);
 
-			using (var cmd = pooledConn.Command("PRAGMA journal_mode=WAL")) {
-				cmd.ExecuteNonQuery();
+			await using (var cmd = pooledConnection.Command("PRAGMA journal_mode=WAL")) {
+				await cmd.ExecuteNonQueryAsync(disposalToken);
 			}
 
-			free.Add(pooledConn);
-		}
-
-		used = new List<PooledConnection>(poolSize);
-	}
-
-	private void ThrowIfDisposed() {
-		ObjectDisposedException.ThrowIf(isDisposed, nameof(SqliteConnectionPool));
-	}
-
-	public ISqliteConnection Take() {
-		while (true) {
-			ThrowIfDisposed();
-
-			lock (monitor) {
-				if (free.TryTake(out var conn)) {
-					used.Add(conn);
-					return conn;
-				}
-				else {
-					Log.ForType<SqliteConnectionPool>().Warn("Thread " + Environment.CurrentManagedThreadId + " is starving for connections.");
+			all.Add(pooledConnection);
+			await free.Push(pooledConnection, disposalToken);
 		}
 	}
 
-			Thread.Sleep(TimeSpan.FromMilliseconds(rand.Next(100, 200)));
-		}
+	public async Task<ISqliteConnection> Take() {
+		return await free.Pop(disposalToken);
 	}
 
-	private void Return(PooledConnection conn) {
-		ThrowIfDisposed();
-
-		lock (monitor) {
-			if (used.Remove(conn)) {
-				free.Add(conn);
-			}
-		}
+	private async Task Return(PooledConnection conn) {
+		await free.Push(conn, disposalToken);
 	}
 
-	public void Dispose() {
-		if (isDisposed) {
+	public async ValueTask DisposeAsync() {
+		if (disposalToken.IsCancellationRequested) {
 			return;
 		}
 
-		isDisposed = true;
+		await disposalTokenSource.CancelAsync();
 		
-		lock (monitor) {
-			while (free.TryTake(out var conn)) {
-				Close(conn.InnerConnection);
+		foreach (var conn in all) {
+			await conn.InnerConnection.CloseAsync();
+			await conn.InnerConnection.DisposeAsync();
 		}
 		
-			foreach (var conn in used) {
-				Close(conn.InnerConnection);
-			}
-
-			free.Dispose();
-			used.Clear();
-		}
-	}
-
-	private static void Close(SqliteConnection conn) {
-		conn.Close();
-		conn.Dispose();
+		disposalTokenSource.Dispose();
 	}
 
 	private sealed class PooledConnection : ISqliteConnection {
@@ -107,8 +84,8 @@ sealed class SqliteConnectionPool : IDisposable {
 			this.InnerConnection = conn;
 		}
 
-		void IDisposable.Dispose() {
-			pool.Return(this);
+		public async ValueTask DisposeAsync() {
+			await pool.Return(this);
 		}
 	}
 }

app/Server/Database/Sqlite/Utils/SqliteExtensions.cs

@@ -58,7 +58,7 @@ static class SqliteExtensions {
 
 	public static SqliteCommand Delete(this ISqliteConnection conn, string tableName, (string Name, SqliteType Type) column) {
 		var cmd = conn.Command("DELETE FROM " + tableName + " WHERE " + column.Name + " = :" + column.Name);
-		CreateParameters(cmd, new[] { column });
+		CreateParameters(cmd, [column]);
 		return cmd;
 	}
 

app/Server/Database/Sqlite/Utils/SqliteWhereGenerator.cs

@@ -5,7 +5,7 @@ namespace DHT.Server.Database.Sqlite.Utils;
 sealed class SqliteWhereGenerator {
 	private readonly string? tableAlias;
 	private readonly bool invert;
-	private readonly List<string> conditions = new ();
+	private readonly List<string> conditions = [];
 
 	public SqliteWhereGenerator(string? tableAlias, bool invert) {
 		this.tableAlias = tableAlias;

app/Server/Service/ServerStartup.cs

@@ -11,12 +11,12 @@ using Microsoft.Extensions.Hosting;
 namespace DHT.Server.Service;
 
 sealed class Startup {
-	private static readonly string[] AllowedOrigins = {
+	private static readonly string[] AllowedOrigins = [
 		"https://discord.com",
 		"https://ptb.discord.com",
 		"https://canary.discord.com",
-		"https://discordapp.com",
-	};
+		"https://discordapp.com"
+	];
 
 	public void ConfigureServices(IServiceCollection services) {
 		services.Configure<JsonOptions>(static options => {

app/Server/State.cs

@@ -22,6 +22,6 @@ public sealed class State : IAsyncDisposable {
 	public async ValueTask DisposeAsync() {
 		await Downloader.Stop();
 		await Server.Stop();
-		Db.Dispose();
+		await Db.DisposeAsync();
 	}
 }

app/Utils/Collections/ConcurrentPool.cs

@@ -0,0 +1,45 @@
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace DHT.Utils.Collections;
+
+public sealed class ConcurrentPool<T> {
+	private readonly SemaphoreSlim mutexSemaphore;
+	private readonly SemaphoreSlim availableItemSemaphore;
+	private readonly Stack<T> items;
+
+	public ConcurrentPool(int size) {
+		mutexSemaphore = new SemaphoreSlim(1);
+		availableItemSemaphore = new SemaphoreSlim(0, size);
+		items = new Stack<T>();
+	}
+
+	public async Task Push(T item, CancellationToken cancellationToken) {
+		await PushItem(item, cancellationToken);
+		availableItemSemaphore.Release();
+	}
+
+	public async Task<T> Pop(CancellationToken cancellationToken) {
+		await availableItemSemaphore.WaitAsync(cancellationToken);
+		return await PopItem(cancellationToken);
+	}
+
+	private async Task PushItem(T item, CancellationToken cancellationToken) {
+		await mutexSemaphore.WaitAsync(cancellationToken);
+		try {
+			items.Push(item);
+		} finally {
+			mutexSemaphore.Release();
+		}
+	}
+
+	private async Task<T> PopItem(CancellationToken cancellationToken) {
+		await mutexSemaphore.WaitAsync(cancellationToken);
+		try {
+			return items.Pop();
+		} finally {
+			mutexSemaphore.Release();
+		}
+	}
+}

app/Utils/Collections/MultiDictionary.cs

@@ -1,19 +0,0 @@
-using System.Collections.Generic;
-
-namespace DHT.Utils.Collections;
-
-public sealed class MultiDictionary<TKey, TValue> where TKey : notnull {
-	private readonly Dictionary<TKey, List<TValue>> dict = new();
-
-	public void Add(TKey key, TValue value) {
-		if (!dict.TryGetValue(key, out var list)) {
-			dict[key] = list = new List<TValue>();
-		}
-
-		list.Add(value);
-	}
-
-	public List<TValue>? GetListOrNull(TKey key) {
-		return dict.TryGetValue(key, out var list) ? list : null;
-	}
-}

app/Utils/Http/HttpOutput.cs

@@ -13,42 +13,20 @@ public static class HttpOutput {
 		}
 	}
 
-	public sealed class Text : IHttpOutput {
-		private readonly string text;
-
-		public Text(string text) {
-			this.text = text;
-		}
-
+	public sealed class Text(string text) : IHttpOutput {
 		public Task WriteTo(HttpResponse response) {
 			return response.WriteAsync(text, Encoding.UTF8);
 		}
 	}
 
-	public sealed class File : IHttpOutput {
-		private readonly string? contentType;
-		private readonly byte[] bytes;
-
-		public File(string? contentType, byte[] bytes) {
-			this.contentType = contentType;
-			this.bytes = bytes;
-		}
-
+	public sealed class File(string? contentType, byte[] bytes) : IHttpOutput {
 		public async Task WriteTo(HttpResponse response) {
 			response.ContentType = contentType ?? string.Empty;
 			await response.Body.WriteAsync(bytes);
 		}
 	}
 
-	public sealed class Redirect : IHttpOutput {
-		private readonly string url;
-		private readonly bool permanent;
-
-		public Redirect(string url, bool permanent) {
-			this.url = url;
-			this.permanent = permanent;
-		}
-
+	public sealed class Redirect(string url, bool permanent) : IHttpOutput {
 		public Task WriteTo(HttpResponse response) {
 			response.Redirect(url, permanent);
 			return Task.CompletedTask;

app/Utils/Http/JsonElementContext.cs

@@ -5,4 +5,4 @@ namespace DHT.Utils.Http;
 
 [JsonSourceGenerationOptions(PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase, GenerationMode = JsonSourceGenerationMode.Default)]
 [JsonSerializable(typeof(JsonElement))]
-public sealed partial class JsonElementContext : JsonSerializerContext {}
+public sealed partial class JsonElementContext : JsonSerializerContext;

app/Utils/Resources/ResourceLoader.cs

@@ -6,13 +6,7 @@ using System.Threading.Tasks;
 
 namespace DHT.Utils.Resources;
 
-public sealed class ResourceLoader {
-	private readonly Assembly assembly;
-
-	public ResourceLoader(Assembly assembly) {
-		this.assembly = assembly;
-	}
-
+public sealed class ResourceLoader(Assembly assembly) {
 	private Stream GetEmbeddedStream(string filename) {
 		Stream? stream = null;
 		foreach (var embeddedName in assembly.GetManifestResourceNames()) {

app/Version.cs

@@ -8,5 +8,5 @@ using DHT.Utils;
 namespace DHT.Utils;
 
 static class Version {
-	public const string Tag = "39.1.0.0";
+	public const string Tag = "40.0.0.0";
 }