fix(core): Converts account packets to spanwriter (#381)

- [X] Converts account packets to spanwriter

Projects/Server/Buffers/CircularBufferWriter.cs

@@ -479,22 +479,6 @@ namespace System.Buffers
             Write((byte)0);
         }
 
-        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public void Clear()
-        {
-            if (Position < _first.Length)
-            {
-                _first.Slice(Position).Clear();
-                _second.Clear();
-            }
-            else
-            {
-                _second.Slice(Position - _first.Length).Clear();
-            }
-
-            Position = Length;
-        }
-
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Clear(int amount)
         {

Projects/Server/Buffers/SpanWriter.cs

@@ -31,7 +31,7 @@ namespace System.Buffers
         private Span<byte> _buffer;
         private int _position;
 
-        public int Length { get; private set; }
+        public int BytesWritten { get; private set; }
 
         public int Position
         {
@@ -40,9 +40,9 @@ namespace System.Buffers
             {
                 _position = value;
 
-                if (value > Length)
+                if (value > BytesWritten)
                 {
-                    Length = value;
+                    BytesWritten = value;
                 }
             }
         }
@@ -58,7 +58,7 @@ namespace System.Buffers
             _resize = resize;
             _buffer = initialBuffer;
             _position = 0;
-            Length = 0;
+            BytesWritten = 0;
             _arrayToReturnToPool = null;
         }
 
@@ -68,16 +68,16 @@ namespace System.Buffers
             _arrayToReturnToPool = ArrayPool<byte>.Shared.Rent(initialCapacity);
             _buffer = _arrayToReturnToPool;
             _position = 0;
-            Length = 0;
+            BytesWritten = 0;
         }
 
         [MethodImpl(MethodImplOptions.NoInlining)]
         private void Grow(int additionalCapacity)
         {
-            var newSize = Math.Max(Length + additionalCapacity, _buffer.Length * 2);
+            var newSize = Math.Max(BytesWritten + additionalCapacity, _buffer.Length * 2);
             byte[] poolArray = ArrayPool<byte>.Shared.Rent(newSize);
 
-            _buffer.Slice(0, Length).CopyTo(poolArray);
+            _buffer.Slice(0, BytesWritten).CopyTo(poolArray);
 
             byte[]? toReturn = _arrayToReturnToPool;
             _buffer = _arrayToReturnToPool = poolArray;
@@ -112,7 +112,7 @@ namespace System.Buffers
                     throw new OutOfMemoryException();
                 }
 
-                Grow(capacity - Length);
+                Grow(capacity - BytesWritten);
             }
         }
 
@@ -161,6 +161,14 @@ namespace System.Buffers
             Position += 4;
         }
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void WriteLE(int value)
+        {
+            GrowIfNeeded(4);
+            BinaryPrimitives.WriteInt32LittleEndian(_buffer.Slice(_position), value);
+            Position += 4;
+        }
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Write(uint value)
         {
@@ -169,6 +177,14 @@ namespace System.Buffers
             Position += 4;
         }
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public void WriteLE(uint value)
+        {
+            GrowIfNeeded(4);
+            BinaryPrimitives.WriteUInt32LittleEndian(_buffer.Slice(_position), value);
+            Position += 4;
+        }
+
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public void Write(long value)
         {
@@ -317,7 +333,7 @@ namespace System.Buffers
             var newPosition = Math.Max(0, origin switch
             {
                 SeekOrigin.Current => _position + offset,
-                SeekOrigin.End     => Length + offset,
+                SeekOrigin.End     => BytesWritten + offset,
                 _                  => offset // Begin
             });
 

Projects/Server/Network/NetState/NetState.cs

@@ -32,7 +32,8 @@ namespace Server.Network
 {
     public delegate void NetStateCreatedCallback(NetState ns);
 
-    public delegate void EncodePacket(ref CircularBuffer<byte> buffer, ref int length);
+    public delegate void DecodePacket(ref CircularBuffer<byte> buffer, ref int length);
+    public delegate void EncodePacket(ReadOnlySpan<byte> inputBuffer, ref CircularBuffer<byte> outputBuffer, out int length);
 
     public partial class NetState : IComparable<NetState>, IDisposable
     {
@@ -54,7 +55,7 @@ namespace Server.Network
         private byte[] _sendBuffer;
         private long m_NextCheckActivity;
         private volatile bool m_Running;
-        private volatile EncodePacket _packetDecoder;
+        private volatile DecodePacket _packetDecoder;
         private volatile EncodePacket _packetEncoder;
 
         internal int m_AuthID;
@@ -115,7 +116,7 @@ namespace Server.Network
 
         public IPAddress Address { get; }
 
-        public EncodePacket PacketDecoder
+        public DecodePacket PacketDecoder
         {
             get => _packetDecoder;
             set => _packetDecoder = value;
@@ -392,8 +393,15 @@ namespace Server.Network
 
             try
             {
-                buffer.CopyFrom(span);
+                if (_packetEncoder != null)
-                _packetEncoder?.Invoke(ref buffer, ref length);
+                {
+                    _packetEncoder(span, ref buffer, out length);
+                }
+                else
+                {
+                    buffer.CopyFrom(span);
+                }
+
                 SendPipe.Writer.Advance((uint)length);
             }
             catch (Exception ex)
@@ -418,7 +426,12 @@ namespace Server.Network
 
             try
             {
-                _packetEncoder?.Invoke(ref buffer, ref length);
+                // _packetEncoder?.Invoke(ref buffer, ref length);
+                if (CompressionEnabled)
+                {
+                    NetworkCompression.Compress(ref buffer, ref length); // This will be changed soon
+                }
+
                 SendPipe.Writer.Advance((uint)length);
             }
             catch (Exception ex)

Projects/Server/Network/NetworkCompression.cs

@@ -125,6 +125,70 @@ namespace Server.Network
             return outputIdx;
         }
 
+        public static void Compress(ReadOnlySpan<byte> input, ref CircularBuffer<byte> output, out int length)
+        {
+            length = Compress(input, ref output);
+        }
+
+        public static int Compress(ReadOnlySpan<byte> input, ref CircularBuffer<byte> output)
+        {
+            if (input.Length > DefiniteOverflow)
+            {
+                return 0;
+            }
+
+            int bitCount = 0;
+            int bitValue = 0;
+
+            int inputIdx = 0;
+            int outputIdx = 0;
+
+            while (inputIdx < input.Length)
+            {
+                int i = input[inputIdx++] << 1;
+
+                bitCount += _huffmanTable[i];
+                bitValue = (bitValue << _huffmanTable[i]) | _huffmanTable[i + 1];
+
+                while (bitCount >= 8)
+                {
+                    bitCount -= 8;
+
+                    if (output.Length < outputIdx + 1)
+                    {
+                        return 0;
+                    }
+
+                    output[outputIdx++] = (byte)(bitValue >> bitCount);
+                }
+            }
+
+            // terminal code
+            bitCount += _huffmanTable[0x200];
+            bitValue = (bitValue << _huffmanTable[0x200]) | _huffmanTable[0x201];
+
+            // align on byte boundary
+            if ((bitCount & 7) != 0)
+            {
+                bitValue <<= 8 - (bitCount & 7);
+                bitCount += 8 - (bitCount & 7);
+            }
+
+            while (bitCount >= 8)
+            {
+                bitCount -= 8;
+
+                if (output.Length < outputIdx + 1)
+                {
+                    return 0;
+                }
+
+                output[outputIdx++] = (byte)(bitValue >> bitCount);
+            }
+
+            return outputIdx;
+        }
+
         public static int Compress(ReadOnlySpan<byte> input, Span<byte> output)
         {
             if (input.Length > DefiniteOverflow)

Projects/Server/Network/Packets/IncomingAccountPackets.cs

@@ -417,6 +417,8 @@ namespace Server.Network
             if (e.Accepted)
             {
                 state.CityInfo = e.CityInfo;
+
+                // Comment out these lines to turn off huffman compression
                 state.CompressionEnabled = true;
                 state.PacketEncoder = NetworkCompression.Compress;
 

Projects/Server/Network/Packets/OutgoingAccountPackets.cs

@@ -61,13 +61,13 @@ namespace Server.Network
          */
         public static void SendChangeCharacter(this NetState ns, IAccount a)
         {
-            if (ns == null || a == null || !ns.GetSendBuffer(out var buffer))
+            if (ns == null || a == null)
             {
                 return;
             }
 
             var length = 5 + a.Length * 60;
-            var writer = new CircularBufferWriter(buffer);
+            var writer = new SpanWriter(stackalloc byte[length]);
 
             writer.Write((byte)0x81); // Packet ID
             writer.Write((ushort)length);
@@ -98,7 +98,7 @@ namespace Server.Network
             writer.Write((byte)count);
             writer.Seek(position, SeekOrigin.Begin);
 
-            ns.Send(ref buffer, writer.Position);
+            ns.Send(writer.Span);
         }
 
         /**
@@ -107,17 +107,7 @@ namespace Server.Network
          *
          * Sends a requests for the client version
          */
-        public static void SendClientVersionRequest(this NetState ns)
+        public static void SendClientVersionRequest(this NetState ns) => ns?.Send(stackalloc byte[] { 0xBD, 0x00, 0x03 });
-        {
-            if (ns != null && ns.GetSendBuffer(out var buffer))
-            {
-                buffer[0] = 0xBD; // Packet ID
-                buffer[1] = 0x00;
-                buffer[2] = 0x03; // Length
-
-                ns.Send(ref buffer, 3);
-            }
-        }
 
         /**
          * Packet: 0x85
@@ -125,16 +115,8 @@ namespace Server.Network
          *
          * Sends the result of a deletion request
          */
-        public static void SendCharacterDeleteResult(this NetState ns, DeleteResultType res)
+        public static void SendCharacterDeleteResult(this NetState ns, DeleteResultType res) =>
-        {
+            ns?.Send(stackalloc byte[] { 0x85, (byte)res });
-            if (ns != null && ns.GetSendBuffer(out var buffer))
-            {
-                buffer[0] = 0x85; // Packet ID
-                buffer[1] = (byte)res;
-
-                ns.Send(ref buffer, 2);
-            }
-        }
 
         /**
          * Packet: 0x53
@@ -142,16 +124,8 @@ namespace Server.Network
          *
          * Sends a PopupMessage with a predetermined message
          */
-        public static void SendPopupMessage(this NetState ns, PMMessage msg)
+        public static void SendPopupMessage(this NetState ns, PMMessage msg) =>
-        {
+            ns?.Send(stackalloc byte[] { 0x53, (byte)msg });
-            if (ns != null && ns.GetSendBuffer(out var buffer))
-            {
-                buffer[0] = 0x53; // Packet ID
-                buffer[1] = (byte)msg;
-
-                ns.Send(ref buffer, 2);
-            }
-        }
 
         /**
          * Packet: 0xB9
@@ -161,7 +135,7 @@ namespace Server.Network
          */
         public static void SendSupportedFeature(this NetState ns)
         {
-            if (ns == null || !ns.GetSendBuffer(out var buffer))
+            if (ns == null)
             {
                 return;
             }
@@ -183,7 +157,8 @@ namespace Server.Network
                 }
             }
 
-            var writer = new CircularBufferWriter(buffer);
+            var length = ns.ExtendedSupportedFeatures ? 5 : 3;
+            var writer = new SpanWriter(stackalloc byte[length]);
             writer.Write((byte)0xB9); // Packet ID
 
             if (ns.ExtendedSupportedFeatures)
@@ -195,7 +170,7 @@ namespace Server.Network
                 writer.Write((ushort)flags);
             }
 
-            ns.Send(ref buffer, ns.ExtendedSupportedFeatures ? 5 : 3);
+            ns.Send(writer.Span);
         }
 
         /**
@@ -206,12 +181,12 @@ namespace Server.Network
          */
         public static void SendLoginConfirmation(this NetState ns, Mobile m)
         {
-            if (ns == null || !ns.GetSendBuffer(out var buffer))
+            if (ns == null)
             {
                 return;
             }
 
-            var writer = new CircularBufferWriter(buffer);
+            var writer = new SpanWriter(stackalloc byte[37]);
             writer.Write((byte)0x1B); // PacketID
             writer.Write(m.Serial);
             writer.Write(0);
@@ -234,9 +209,9 @@ namespace Server.Network
 
             writer.Write((short)(map?.Width ?? Map.Felucca.Width));
             writer.Write((short)(map?.Height ?? Map.Felucca.Height));
-            writer.Clear();
+            writer.Clear(writer.Capacity - writer.Position); // Remaining is zero
 
-            ns.Send(ref buffer, 37);
+            ns.Send(writer.Span);
         }
 
         /**
@@ -247,12 +222,7 @@ namespace Server.Network
          */
         public static void SendLoginComplete(this NetState ns)
         {
-            if (ns != null && ns.GetSendBuffer(out var buffer))
+            ns?.Send(stackalloc byte[] { 0x55 });
-            {
-                buffer[0] = 0x55; // Packet ID
-
-                ns.Send(ref buffer, 1);
-            }
         }
 
         /**
@@ -268,10 +238,6 @@ namespace Server.Network
                 return;
             }
 
-            var writer = new CircularBufferWriter(buffer);
-            writer.Write((byte)0x86); // Packet ID
-            writer.Seek(2, SeekOrigin.Current); // Length
-
             var highSlot = -1;
 
             for (var i = a.Length - 1; i >= 0; i--)
@@ -284,6 +250,11 @@ namespace Server.Network
             }
 
             var count = Math.Max(Math.Max(highSlot + 1, a.Limit), 5);
+            var length = 4 + count * 60;
+            var writer = new SpanWriter(stackalloc byte[length]);
+            writer.Write((byte)0x86); // Packet ID
+            writer.Write((ushort)length);
+
             writer.Write((byte)count);
 
             for (int i = 0; i < count; i++)
@@ -302,8 +273,7 @@ namespace Server.Network
                 }
             }
 
-            writer.WritePacketLength();
+            ns.Send(writer.Span);
-            ns.Send(ref buffer, writer.Position);
         }
 
         /**
@@ -316,7 +286,7 @@ namespace Server.Network
         {
             var acct = ns?.Account;
 
-            if (acct == null || !ns.GetSendBuffer(out var buffer))
+            if (acct == null)
             {
                 return;
             }
@@ -326,10 +296,6 @@ namespace Server.Network
 
             var cityInfo = ns.CityInfo;
 
-            var writer = new CircularBufferWriter(buffer);
-            writer.Write((byte)0xA9); // Packet ID
-            writer.Seek(2, SeekOrigin.Current); // Length
-
             var highSlot = -1;
 
             for (var i = acct.Length - 1; i >= 0; i--)
@@ -342,6 +308,12 @@ namespace Server.Network
             }
 
             var count = Math.Max(Math.Max(highSlot + 1, acct.Limit), 5);
+            var length = (client70130 ?
+                11 + (textLength * 2 + 25) * cityInfo.Length :
+                 9 + (textLength * 2 +  1) * cityInfo.Length) + count * 60;
+            var writer = new SpanWriter(stackalloc byte[length]);
+            writer.Write((byte)0xA9); // Packet ID
+            writer.Write((ushort)length);
             writer.Write((byte)count);
 
             for (int i = 0; i < count; i++)
@@ -403,8 +375,7 @@ namespace Server.Network
                 writer.Write((short)-1);
             }
 
-            writer.WritePacketLength();
+            ns.Send(writer.Span);
-            ns.Send(ref buffer, writer.Position);
         }
 
         /**
@@ -413,37 +384,28 @@ namespace Server.Network
          *
          * Sends a reason for rejecting the login
          */
-        public static void SendAccountLoginRejected(this NetState ns, ALRReason reason)
+        public static void SendAccountLoginRejected(this NetState ns, ALRReason reason) =>
-        {
+            ns?.Send(stackalloc byte[] { 0x82, (byte)reason });
-            if (ns != null && ns.GetSendBuffer(out var buffer))
-            {
-                buffer[0] = 0x82; // Packet ID
-                buffer[1] = (byte)reason;
-
-                ns.Send(ref buffer, 2);
-            }
-        }
 
         /**
          * Packet: 0xA8
-         * Length: up to 240 bytes
+         * Length: 6 + 40 bytes per server listing
          *
          * Sends login acknowledge with server listing
          */
         public static void SendAccountLoginAck(this NetState ns)
         {
-            if (ns == null || !ns.GetSendBuffer(out var buffer))
+            if (ns == null)
             {
                 return;
             }
 
-            var writer = new CircularBufferWriter(buffer);
-            writer.Write((byte)0xA8); // Packet ID
-            writer.Seek(2, SeekOrigin.Current); // Length
-
-            writer.Write((byte)0x5D);
-
             var info = ns.ServerInfo;
+            var length = 6 + 40 * info.Length;
+            var writer = new SpanWriter(stackalloc byte[length]);
+            writer.Write((byte)0xA8); // Packet ID
+            writer.Write((ushort)length);
+            writer.Write((byte)0x5D);
             writer.Write((ushort)info.Length);
 
             for (var i = 0; i < info.Length; ++i)
@@ -458,8 +420,7 @@ namespace Server.Network
                 writer.Write(si.RawAddress);
             }
 
-            writer.WritePacketLength();
+            ns.Send(writer.Span);
-            ns.Send(ref buffer, writer.Position);
         }
 
         /**
@@ -470,19 +431,19 @@ namespace Server.Network
          */
         public static void SendPlayServerAck(this NetState ns, ServerInfo si, int authId)
         {
-            if (ns == null || !ns.GetSendBuffer(out var buffer))
+            if (ns == null)
             {
                 return;
             }
 
-            var writer = new CircularBufferWriter(buffer);
+            var writer = new SpanWriter(stackalloc byte[11]);
             writer.Write((byte)0x8C); // Packet ID
 
             writer.WriteLE(si.RawAddress);
             writer.Write((short)si.Address.Port);
             writer.Write(authId);
 
-            ns.Send(ref buffer, writer.Position);
+            ns.Send(writer.Span);
         }
     }
 }

Projects/UOContent/Skills/Tracking/OutgoingArrowPackets.cs

@@ -28,12 +28,12 @@ namespace Server.Network
 
         public static void SendArrow(this NetState ns, byte command, int x, int y, Serial s)
         {
-            if (ns == null || !ns.GetSendBuffer(out var buffer))
+            if (ns == null)
             {
                 return;
             }
 
-            var writer = new CircularBufferWriter(buffer);
+            var writer = new SpanWriter(stackalloc byte[10]);
             writer.Write((byte)0xBA); // Packet ID
             writer.Write(command);
 
@@ -55,7 +55,7 @@ namespace Server.Network
                 writer.Write((short)-1);
             }
 
-            ns.Send(ref buffer, writer.Position);
+            ns.Send(writer.Span);
         }
     }
 }