Use Utf8Formatter to prepare statements.

Create ByteBufferWriter class that abstracts an expandable output buffer (similar to BinaryWriter over MemoryStream). Replace PayloadWriter with ByteBufferWriter.

Use ArrayPool for the buffers that are allocated.

Signed-off-by: Bradley Grainger <[email protected]>

Author: bgrainger

src/MySqlConnector/Core/ServerSession.cs

@@ -323,8 +323,8 @@ public async Task ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer
 				if (m_supportsConnectionAttributes && s_connectionAttributes == null)
 					s_connectionAttributes = CreateConnectionAttributes();
 
-				payload = HandshakeResponse41Payload.Create(initialHandshake, cs, m_useCompression, m_supportsConnectionAttributes ? s_connectionAttributes : null);
-				await SendReplyAsync(payload, ioBehavior, cancellationToken).ConfigureAwait(false);
+				using (var handshakeResponsePayload = HandshakeResponse41Payload.Create(initialHandshake, cs, m_useCompression, m_supportsConnectionAttributes ? s_connectionAttributes : null))
+					await SendReplyAsync(handshakeResponsePayload, ioBehavior, cancellationToken).ConfigureAwait(false);
 				payload = await ReceiveReplyAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
 
 				// if server doesn't support the authentication fast path, it will send a new challenge
@@ -378,9 +378,9 @@ public async Task<bool> TryResetConnectionAsync(ConnectionSettings cs, IOBehavio
 					m_logArguments[1] = ServerVersion.OriginalString;
 					Log.Debug("Session{0} ServerVersion={1} doesn't support reset connection; sending change user request", m_logArguments);
 					var hashedPassword = AuthenticationUtility.CreateAuthenticationResponse(AuthPluginData, 0, cs.Password);
-					var payload = ChangeUserPayload.Create(cs.UserID, hashedPassword, cs.Database, m_supportsConnectionAttributes ? s_connectionAttributes : null);
-					await SendAsync(payload, ioBehavior, cancellationToken).ConfigureAwait(false);
-					payload = await ReceiveReplyAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
+					using (var changeUserPayload = ChangeUserPayload.Create(cs.UserID, hashedPassword, cs.Database, m_supportsConnectionAttributes ? s_connectionAttributes : null))
+						await SendAsync(changeUserPayload, ioBehavior, cancellationToken).ConfigureAwait(false);
+					var payload = await ReceiveReplyAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
 					if (payload.HeaderByte == AuthenticationMethodSwitchRequestPayload.Signature)
 					{
 						Log.Debug("Session{0} optimistic reauthentication failed; logging in again", m_logArguments);
@@ -942,8 +942,8 @@ bool ValidateRemoteCertificate(object rcbSender, X509Certificate rcbCertificate,
 
 			var checkCertificateRevocation = cs.SslMode == MySqlSslMode.VerifyFull;
 
-			var initSsl = HandshakeResponse41Payload.CreateWithSsl(serverCapabilities, cs, m_useCompression);
-			await SendReplyAsync(initSsl, ioBehavior, cancellationToken).ConfigureAwait(false);
+			using (var initSsl = HandshakeResponse41Payload.CreateWithSsl(serverCapabilities, cs, m_useCompression))
+				await SendReplyAsync(initSsl, ioBehavior, cancellationToken).ConfigureAwait(false);
 
 			try
 			{
@@ -1172,7 +1172,7 @@ private void VerifyState(State state1, State state2, State state3)
 		private byte[] CreateConnectionAttributes()
 		{
 			Log.Debug("Session{0} creating connection attributes", m_logArguments);
-			var attributesWriter = new PayloadWriter();
+			var attributesWriter = new ByteBufferWriter();
 			attributesWriter.WriteLengthEncodedString("_client_name");
 			attributesWriter.WriteLengthEncodedString("MySqlConnector");
 			attributesWriter.WriteLengthEncodedString("_client_version");
@@ -1198,12 +1198,15 @@ private byte[] CreateConnectionAttributes()
 				attributesWriter.WriteLengthEncodedString("_pid");
 				attributesWriter.WriteLengthEncodedString(process.Id.ToString(CultureInfo.InvariantCulture));
 			}
-			var connectionAttributes = attributesWriter.ToBytes();
-
-			var writer = new PayloadWriter();
-			writer.WriteLengthEncodedInteger((ulong) connectionAttributes.Length);
-			writer.Write(connectionAttributes);
-			return writer.ToBytes();
+			using (var connectionAttributesPayload = attributesWriter.ToPayloadData())
+			{
+				var connectionAttributes = connectionAttributesPayload.ArraySegment;
+				var writer = new ByteBufferWriter(connectionAttributes.Count + 9);
+				writer.WriteLengthEncodedInteger((ulong) connectionAttributes.Count);
+				writer.Write(connectionAttributes);
+				using (var payload = writer.ToPayloadData())
+					return payload.ArraySegment.AsSpan().ToArray();
+			}
 		}
 
 		private Exception CreateExceptionForErrorPayload(PayloadData payload)

src/MySqlConnector/Core/StatementPreparer.cs

@@ -1,9 +1,8 @@
 using System;
 using System.Data;
-using System.IO;
-using System.Text;
 using MySql.Data.MySqlClient;
 using MySqlConnector.Protocol;
+using MySqlConnector.Protocol.Serialization;
 using MySqlConnector.Utilities;
 
 namespace MySqlConnector.Core
@@ -19,29 +18,21 @@ public StatementPreparer(string commandText, MySqlParameterCollection parameters
 
 		public ArraySegment<byte> ParseAndBindParameters()
 		{
-			using (var stream = new MemoryStream(m_commandText.Length + 1))
-			using (var writer = new BinaryWriter(stream, Encoding.UTF8))
-			{
-				writer.Write((byte) CommandKind.Query);
-
-				if (!string.IsNullOrWhiteSpace(m_commandText))
-				{
-					var parser = new ParameterSqlParser(this, writer);
-					parser.Parse(m_commandText);
-				}
+			var writer = new ByteBufferWriter(m_commandText.Length + 1);
+			writer.Write((byte) CommandKind.Query);
 
-#if NETSTANDARD1_3
-				var array = stream.ToArray();
-#else
-				var array = stream.GetBuffer();
-#endif
-				return new ArraySegment<byte>(array, 0, checked((int) stream.Length));
+			if (!string.IsNullOrWhiteSpace(m_commandText))
+			{
+				var parser = new ParameterSqlParser(this, writer);
+				parser.Parse(m_commandText);
 			}
+
+			return writer.ArraySegment;
 		}
 
 		private sealed class ParameterSqlParser : SqlParser
 		{
-			public ParameterSqlParser(StatementPreparer preparer, BinaryWriter writer)
+			public ParameterSqlParser(StatementPreparer preparer, ByteBufferWriter writer)
 			{
 				m_preparer = preparer;
 				m_writer = writer;
@@ -84,11 +75,11 @@ protected override void OnParsed()
 
 			private void AppendString(string value, int offset, int length)
 			{
-				m_writer.WriteUtf8(value, offset, length);
+				m_writer.Write(value, offset, length);
 			}
 
 			readonly StatementPreparer m_preparer;
-			readonly BinaryWriter m_writer;
+			readonly ByteBufferWriter m_writer;
 			int m_currentParameterIndex;
 			int m_lastIndex;
 		}

src/MySqlConnector/Core/TextCommandExecutor.cs

@@ -62,7 +62,7 @@ public virtual async Task<DbDataReader> ExecuteReaderAsync(string commandText, M
 			cancellationToken.ThrowIfCancellationRequested();
 			if (Log.IsDebugEnabled())
 				Log.Debug("Session{0} ExecuteBehavior {1} CommandText: {2}", m_command.Connection.Session.Id, ioBehavior, commandText);
-			var payload = CreateQueryPayload(commandText, parameterCollection);
+			using (var payload = CreateQueryPayload(commandText, parameterCollection))
 			using (m_command.RegisterCancel(cancellationToken))
 			{
 				m_command.Connection.Session.StartQuerying(m_command);
@@ -119,7 +119,7 @@ private PayloadData CreateQueryPayload(string commandText, MySqlParameterCollect
 			}
 
 			var preparer = new StatementPreparer(commandText, parameterCollection, statementPreparerOptions);
-			return new PayloadData(preparer.ParseAndBindParameters());
+			return new PayloadData(preparer.ParseAndBindParameters(), isPooled: true);
 		}
 
 		static readonly IMySqlConnectorLogger Log = MySqlConnectorLogManager.CreateLogger(nameof(TextCommandExecutor));

src/MySqlConnector/MySql.Data.MySqlClient/MySqlConnection.cs

@@ -124,7 +124,8 @@ private async Task ChangeDatabaseAsync(IOBehavior ioBehavior, string databaseNam
 
 			CloseDatabase();
 
-			await m_session.SendAsync(InitDatabasePayload.Create(databaseName), ioBehavior, cancellationToken).ConfigureAwait(false);
+			using (var initDatabasePayload = InitDatabasePayload.Create(databaseName))
+				await m_session.SendAsync(initDatabasePayload, ioBehavior, cancellationToken).ConfigureAwait(false);
 			var payload = await m_session.ReceiveReplyAsync(ioBehavior, cancellationToken).ConfigureAwait(false);
 			OkPayload.Create(payload);
 			m_session.DatabaseOverride = databaseName;

src/MySqlConnector/MySql.Data.MySqlClient/MySqlParameter.cs

@@ -1,8 +1,10 @@
 using System;
+using System.Buffers.Text;
 using System.Data;
 using System.Data.Common;
-using System.IO;
+using System.Diagnostics;
 using MySqlConnector.Core;
+using MySqlConnector.Protocol.Serialization;
 using MySqlConnector.Utilities;
 
 namespace MySql.Data.MySqlClient
@@ -175,16 +177,16 @@ private MySqlParameter(MySqlParameter other, string parameterName)
 
 		internal string NormalizedParameterName { get; private set; }
 
-		internal void AppendSqlString(BinaryWriter writer, StatementPreparerOptions options, string parameterName)
+		internal void AppendSqlString(ByteBufferWriter writer, StatementPreparerOptions options, string parameterName)
 		{
 			if (Value == null || Value == DBNull.Value)
 			{
-				writer.WriteUtf8("NULL");
+				writer.Write(s_nullBytes);
 			}
 			else if (Value is string stringValue)
 			{
 				writer.Write((byte) '\'');
-				writer.WriteUtf8(stringValue.Replace("\\", "\\\\").Replace("'", "\\'"));
+				writer.Write(stringValue.Replace("\\", "\\\\").Replace("'", "\\'"));
 				writer.Write((byte) '\'');
 			}
 			else if (Value is char charValue)
@@ -199,44 +201,70 @@ internal void AppendSqlString(BinaryWriter writer, StatementPreparerOptions opti
 					break;
 
 				default:
-					writer.WriteUtf8(charValue.ToString());
+					writer.Write(charValue.ToString());
 					break;
 				}
 				writer.Write((byte) '\'');
 			}
-			else if (Value is byte || Value is sbyte || Value is short || Value is int || Value is long || Value is ushort || Value is uint || Value is ulong || Value is decimal)
+			else if (Value is byte || Value is sbyte || Value is decimal)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant(Value));
+				writer.Write("{0}".FormatInvariant(Value));
+			}
+			else if (Value is short shortValue)
+			{
+				writer.WriteString(shortValue);
+			}
+			else if (Value is ushort ushortValue)
+			{
+				writer.WriteString(ushortValue);
+			}
+			else if (Value is int intValue)
+			{
+				writer.WriteString(intValue);
+			}
+			else if (Value is uint uintValue)
+			{
+				writer.WriteString(uintValue);
+			}
+			else if (Value is long longValue)
+			{
+				writer.WriteString(longValue);
+			}
+			else if (Value is ulong ulongValue)
+			{
+				writer.WriteString(ulongValue);
 			}
 			else if (Value is byte[] byteArrayValue)
 			{
 				// determine the number of bytes to be written
-				const string c_prefix = "_binary'";
-				var length = byteArrayValue.Length + c_prefix.Length + 1;
+				var length = byteArrayValue.Length + s_binaryBytes.Length + 1;
 				foreach (var by in byteArrayValue)
 				{
 					if (by == 0x27 || by == 0x5C)
 						length++;
 				}
 
-				((MemoryStream) writer.BaseStream).Capacity = (int) writer.BaseStream.Length + length;
-
-				writer.WriteUtf8(c_prefix);
+				var span = writer.GetSpan(length);
+				s_binaryBytes.CopyTo(span);
+				var index = s_binaryBytes.Length;
 				foreach (var by in byteArrayValue)
 				{
 					if (by == 0x27 || by == 0x5C)
-						writer.Write((byte) 0x5C);
-					writer.Write(by);
+						span[index++] = 0x5C;
+					span[index++] = by;
 				}
-				writer.Write((byte) '\'');
+				span[index++] = 0x27;
+				Debug.Assert(index == length, "index == length");
+				writer.Advance(index);
 			}
 			else if (Value is bool boolValue)
 			{
-				writer.WriteUtf8(boolValue ? "true" : "false");
+				writer.Write(boolValue ? s_trueBytes : s_falseBytes);
 			}
 			else if (Value is float || Value is double)
 			{
-				writer.WriteUtf8("{0:R}".FormatInvariant(Value));
+				// NOTE: Utf8Formatter doesn't support "R"
+				writer.Write("{0:R}".FormatInvariant(Value));
 			}
 			else if (Value is DateTime dateTimeValue)
 			{
@@ -245,22 +273,22 @@ internal void AppendSqlString(BinaryWriter writer, StatementPreparerOptions opti
 				else if ((options & StatementPreparerOptions.DateTimeLocal) != 0 && dateTimeValue.Kind == DateTimeKind.Utc)
 					throw new MySqlException("DateTime.Kind must not be Utc when DateTimeKind setting is Local (parameter name: {0})".FormatInvariant(parameterName));
 
-				writer.WriteUtf8("timestamp('{0:yyyy'-'MM'-'dd' 'HH':'mm':'ss'.'ffffff}')".FormatInvariant(dateTimeValue));
+				writer.Write("timestamp('{0:yyyy'-'MM'-'dd' 'HH':'mm':'ss'.'ffffff}')".FormatInvariant(dateTimeValue));
 			}
 			else if (Value is DateTimeOffset dateTimeOffsetValue)
 			{
 				// store as UTC as it will be read as such when deserialized from a timespan column
-				writer.WriteUtf8("timestamp('{0:yyyy'-'MM'-'dd' 'HH':'mm':'ss'.'ffffff}')".FormatInvariant(dateTimeOffsetValue.UtcDateTime));
+				writer.Write("timestamp('{0:yyyy'-'MM'-'dd' 'HH':'mm':'ss'.'ffffff}')".FormatInvariant(dateTimeOffsetValue.UtcDateTime));
 			}
 			else if (Value is TimeSpan ts)
 			{
-				writer.WriteUtf8("time '");
+				writer.Write("time '");
 				if (ts.Ticks < 0)
 				{
 					writer.Write((byte) '-');
 					ts = TimeSpan.FromTicks(-ts.Ticks);
 				}
-				writer.WriteUtf8("{0}:{1:mm':'ss'.'ffffff}'".FormatInvariant(ts.Days * 24 + ts.Hours, ts));
+				writer.Write("{0}:{1:mm':'ss'.'ffffff}'".FormatInvariant(ts.Days * 24 + ts.Hours, ts));
 			}
 			else if (Value is Guid guidValue)
 			{
@@ -287,7 +315,7 @@ internal void AppendSqlString(BinaryWriter writer, StatementPreparerOptions opti
 							Utility.SwapBytes(bytes, 1, 3);
 						}
 					}
-					writer.WriteUtf8("_binary'");
+					writer.Write(s_binaryBytes);
 					foreach (var by in bytes)
 					{
 						if (by == 0x27 || by == 0x5C)
@@ -296,46 +324,48 @@ internal void AppendSqlString(BinaryWriter writer, StatementPreparerOptions opti
 					}
 					writer.Write((byte) '\'');
 				}
-				else if (guidOptions == StatementPreparerOptions.GuidFormatChar32)
-				{
-					writer.WriteUtf8("'{0:N}'".FormatInvariant(guidValue));
-				}
 				else
 				{
-					writer.WriteUtf8("'{0:D}'".FormatInvariant(guidValue));
+					var is32Characters = guidOptions == StatementPreparerOptions.GuidFormatChar32;
+					var guidLength = is32Characters ? 34 : 38;
+					var span = writer.GetSpan(guidLength);
+					span[0] = 0x27;
+					Utf8Formatter.TryFormat(guidValue, span.Slice(1), out _, is32Characters ? 'N' : 'D');
+					span[guidLength - 1] = 0x27;
+					writer.Advance(guidLength);
 				}
 			}
 			else if (MySqlDbType == MySqlDbType.Int16)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant((short) Value));
+				writer.WriteString((short) Value);
 			}
 			else if (MySqlDbType == MySqlDbType.UInt16)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant((ushort) Value));
+				writer.WriteString((ushort) Value);
 			}
 			else if (MySqlDbType == MySqlDbType.Int32)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant((int) Value));
+				writer.WriteString((int) Value);
 			}
 			else if (MySqlDbType == MySqlDbType.UInt32)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant((uint) Value));
+				writer.WriteString((uint) Value);
 			}
 			else if (MySqlDbType == MySqlDbType.Int64)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant((long) Value));
+				writer.WriteString((long) Value);
 			}
 			else if (MySqlDbType == MySqlDbType.UInt64)
 			{
-				writer.WriteUtf8("{0}".FormatInvariant((ulong) Value));
+				writer.WriteString((ulong) Value);
 			}
 			else if ((MySqlDbType == MySqlDbType.String || MySqlDbType == MySqlDbType.VarChar) && HasSetDbType && Value is Enum)
 			{
-				writer.WriteUtf8("'{0:G}'".FormatInvariant(Value));
+				writer.Write("'{0:G}'".FormatInvariant(Value));
 			}
 			else if (Value is Enum)
 			{
-				writer.WriteUtf8("{0:d}".FormatInvariant(Value));
+				writer.Write("{0:d}".FormatInvariant(Value));
 			}
 			else
 			{
@@ -357,6 +387,11 @@ internal static string NormalizeParameterName(string name)
 			return name.StartsWith("@", StringComparison.Ordinal) || name.StartsWith("?", StringComparison.Ordinal) ? name.Substring(1) : name;
 		}
 
+		static readonly byte[] s_nullBytes = { 0x4E, 0x55, 0x4C, 0x4C }; // NULL
+		static readonly byte[] s_trueBytes = { 0x74, 0x72, 0x75, 0x65 }; // true
+		static readonly byte[] s_falseBytes = { 0x66, 0x61, 0x6C, 0x73, 0x65 }; // false
+		static readonly byte[] s_binaryBytes = { 0x5F, 0x62, 0x69, 0x6E, 0x61, 0x72, 0x79, 0x27 }; // _binary'
+
 		DbType m_dbType;
 		MySqlDbType m_mySqlDbType;
 		string m_name;