Review changes

Lidgren.Network/Lidgren.Network.csproj

@@ -5,8 +5,8 @@
         <AssemblyName>SpaceWizards.Lidgren.Network</AssemblyName>
         <IncludeSymbols>true</IncludeSymbols>
         <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
-		<Nullable>enable</Nullable>
-		<LangVersion>latest</LangVersion>
+        <Nullable>enable</Nullable>
+        <LangVersion>11.0</LangVersion>
 
         <!-- Uncomment the following line to not get statistics in RELEASE mode -->
         <DefineConstants>$(DefineConstants);USE_RELEASE_STATISTICS</DefineConstants>

Lidgren.Network/NetBigInteger.cs

@@ -53,6 +53,7 @@ private static int GetByteLength(
 
 		private NetBigInteger()
 		{
+			m_magnitude = null!;
 		}
 
 		private NetBigInteger(
@@ -1131,10 +1132,8 @@ public NetBigInteger ModPow(
 
 			yVal = new int[m.m_magnitude.Length];
 
-			if (zVal == null || yAccum == null)
-			{
-				throw new InvalidOperationException("both zVal and yAccum should not be null");
-			}
+			NetException.ThrowIfNull(zVal);
+			NetException.ThrowIfNull(yAccum);
 
 			//
 			// from LSW to MSW

Lidgren.Network/NetBuffer.Peek.cs

@@ -39,7 +39,7 @@ public partial class NetBuffer
 		public bool PeekBoolean()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 1, c_readOverflowError);
-			byte retval = NetBitWriter.ReadByte(BufferData, 1, m_readPosition);
+			byte retval = NetBitWriter.ReadByte(Data, 1, m_readPosition);
 			return (retval > 0 ? true : false);
 		}
 
@@ -52,7 +52,7 @@ public bool PeekBoolean()
 		public byte PeekByte()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 8, c_readOverflowError);
-			byte retval = NetBitWriter.ReadByte(BufferData, 8, m_readPosition);
+			byte retval = NetBitWriter.ReadByte(Data, 8, m_readPosition);
 			return retval;
 		}
 
@@ -63,7 +63,7 @@ public byte PeekByte()
 		public sbyte PeekSByte()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 8, c_readOverflowError);
-			byte retval = NetBitWriter.ReadByte(BufferData, 8, m_readPosition);
+			byte retval = NetBitWriter.ReadByte(Data, 8, m_readPosition);
 			return (sbyte)retval;
 		}
 
@@ -72,7 +72,7 @@ public sbyte PeekSByte()
 		/// </summary>
 		public byte PeekByte(int numberOfBits)
 		{
-			byte retval = NetBitWriter.ReadByte(BufferData, numberOfBits, m_readPosition);
+			byte retval = NetBitWriter.ReadByte(Data, numberOfBits, m_readPosition);
 			return retval;
 		}
 
@@ -86,7 +86,7 @@ public Span<byte> PeekBytes(Span<byte> into)
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= (into.Length * 8), c_readOverflowError);
 
-			NetBitWriter.ReadBytes(BufferData, m_readPosition, into);
+			NetBitWriter.ReadBytes(Data, m_readPosition, into);
 
 			return into;
 		}
@@ -119,7 +119,7 @@ public void PeekBytes(byte[] into, int offset, int numberOfBytes)
 		public short PeekInt16()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 16, c_readOverflowError);
-			uint retval = NetBitWriter.ReadUInt16(BufferData, 16, m_readPosition);
+			uint retval = NetBitWriter.ReadUInt16(Data, 16, m_readPosition);
 			return (short)retval;
 		}
 
@@ -130,7 +130,7 @@ public short PeekInt16()
 		public ushort PeekUInt16()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 16, c_readOverflowError);
-			uint retval = NetBitWriter.ReadUInt16(BufferData, 16, m_readPosition);
+			uint retval = NetBitWriter.ReadUInt16(Data, 16, m_readPosition);
 			return (ushort)retval;
 		}
 
@@ -143,7 +143,7 @@ public ushort PeekUInt16()
 		public int PeekInt32()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 32, c_readOverflowError);
-			uint retval = NetBitWriter.ReadUInt32(BufferData, 32, m_readPosition);
+			uint retval = NetBitWriter.ReadUInt32(Data, 32, m_readPosition);
 			return (int)retval;
 		}
 
@@ -155,7 +155,7 @@ public int PeekInt32(int numberOfBits)
 			NetException.Assert((numberOfBits > 0 && numberOfBits <= 32), "ReadInt() can only read between 1 and 32 bits");
 			NetException.Assert(m_bitLength - m_readPosition >= numberOfBits, c_readOverflowError);
 
-			uint retval = NetBitWriter.ReadUInt32(BufferData, numberOfBits, m_readPosition);
+			uint retval = NetBitWriter.ReadUInt32(Data, numberOfBits, m_readPosition);
 
 			if (numberOfBits == 32)
 				return (int)retval;
@@ -180,7 +180,7 @@ public int PeekInt32(int numberOfBits)
 		public uint PeekUInt32()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 32, c_readOverflowError);
-			uint retval = NetBitWriter.ReadUInt32(BufferData, 32, m_readPosition);
+			uint retval = NetBitWriter.ReadUInt32(Data, 32, m_readPosition);
 			return retval;
 		}
 
@@ -193,7 +193,7 @@ public uint PeekUInt32(int numberOfBits)
 			NetException.Assert((numberOfBits > 0 && numberOfBits <= 32), "ReadUInt() can only read between 1 and 32 bits");
 			//NetException.Assert(m_bitLength - m_readBitPtr >= numberOfBits, "tried to read past buffer size");
 
-			uint retval = NetBitWriter.ReadUInt32(BufferData, numberOfBits, m_readPosition);
+			uint retval = NetBitWriter.ReadUInt32(Data, numberOfBits, m_readPosition);
 			return retval;
 		}
 
@@ -208,8 +208,8 @@ public ulong PeekUInt64()
 		{
 			NetException.Assert(m_bitLength - m_readPosition >= 64, c_readOverflowError);
 
-			ulong low = NetBitWriter.ReadUInt32(BufferData, 32, m_readPosition);
-			ulong high = NetBitWriter.ReadUInt32(BufferData, 32, m_readPosition + 32);
+			ulong low = NetBitWriter.ReadUInt32(Data, 32, m_readPosition);
+			ulong high = NetBitWriter.ReadUInt32(Data, 32, m_readPosition + 32);
 
 			ulong retval = low + (high << 32);
 
@@ -242,12 +242,12 @@ public ulong PeekUInt64(int numberOfBits)
 			ulong retval;
 			if (numberOfBits <= 32)
 			{
-				retval = (ulong)NetBitWriter.ReadUInt32(BufferData, numberOfBits, m_readPosition);
+				retval = (ulong)NetBitWriter.ReadUInt32(Data, numberOfBits, m_readPosition);
 			}
 			else
 			{
-				retval = NetBitWriter.ReadUInt32(BufferData, 32, m_readPosition);
-				retval |= (ulong)NetBitWriter.ReadUInt32(BufferData, numberOfBits - 32, m_readPosition + 32) << 32;
+				retval = NetBitWriter.ReadUInt32(Data, 32, m_readPosition);
+				retval |= (ulong)NetBitWriter.ReadUInt32(Data, numberOfBits - 32, m_readPosition + 32) << 32;
 			}
 			return retval;
 		}
@@ -299,7 +299,7 @@ public float PeekSingle()
 
 			if ((m_readPosition & 7) == 0) // read directly
 			{
-				float retval = BitConverter.ToSingle(BufferData, m_readPosition >> 3);
+				float retval = BitConverter.ToSingle(Data, m_readPosition >> 3);
 				return retval;
 			}
 
@@ -317,7 +317,7 @@ public double PeekDouble()
 			if ((m_readPosition & 7) == 0) // read directly
 			{
 				// read directly
-				double retval = BitConverter.ToDouble(BufferData, m_readPosition >> 3);
+				double retval = BitConverter.ToDouble(Data, m_readPosition >> 3);
 				return retval;
 			}
 

Lidgren.Network/NetBuffer.Read.cs

@@ -84,7 +84,7 @@ public Span<byte> ReadBytes(Span<byte> into)
 		{
 			NetException.Assert(m_bitLength - m_readPosition + 7 >= (into.Length * 8), c_readOverflowError);
 
-			NetBitWriter.ReadBytes(m_data, m_readPosition, into);
+			NetBitWriter.ReadBytes(Data, m_readPosition, into);
 			m_readPosition += (8 * into.Length);
 			return into;
 		}
@@ -111,7 +111,7 @@ public bool ReadBytes(int numberOfBytes, [MaybeNullWhen(false)] out byte[] resul
 			}
 
 			result = new byte[numberOfBytes];
-			NetBitWriter.ReadBytes(BufferData, numberOfBytes, m_readPosition, result, 0);
+			NetBitWriter.ReadBytes(Data, numberOfBytes, m_readPosition, result, 0);
 			m_readPosition += (8 * numberOfBytes);
 			return true;
 		}
@@ -126,7 +126,7 @@ public bool TryReadBytes(Span<byte> into)
 				return false;
 			}
 
-			NetBitWriter.ReadBytes(m_data, m_readPosition, into);
+			NetBitWriter.ReadBytes(Data, m_readPosition, into);
 			m_readPosition += (8 * into.Length);
 			return true;
 		}
@@ -142,7 +142,7 @@ public void ReadBytes(byte[] into, int offset, int numberOfBytes)
 			NetException.Assert(m_bitLength - m_readPosition + 7 >= (numberOfBytes * 8), c_readOverflowError);
 			NetException.Assert(offset + numberOfBytes <= into.Length);
 
-			NetBitWriter.ReadBytes(m_data, numberOfBytes, m_readPosition, into, offset);
+			NetBitWriter.ReadBytes(Data, numberOfBytes, m_readPosition, into, offset);
 			m_readPosition += (8 * numberOfBytes);
 			return;
 		}
@@ -160,7 +160,7 @@ public void ReadBits(Span<byte> into, int numberOfBits)
 			int numberOfWholeBytes = numberOfBits / 8;
 			int extraBits = numberOfBits - (numberOfWholeBytes * 8);
 
-			NetBitWriter.ReadBytes(m_data, m_readPosition, into.Slice(0, numberOfWholeBytes));
+			NetBitWriter.ReadBytes(Data, m_readPosition, into.Slice(0, numberOfWholeBytes));
 			m_readPosition += (8 * numberOfWholeBytes);
 
 			if (extraBits > 0)
@@ -598,7 +598,7 @@ public string ReadString()
 		/// <summary>
 		/// Reads a string written using Write(string) and returns true for success
 		/// </summary>
-		public bool ReadString(out string result)
+		public bool ReadString([MaybeNullWhen(false)] out string result)
 		{
 			if (ReadVariableUInt32(out uint byteLen) == false)
 			{
@@ -645,7 +645,7 @@ public bool ReadString(out string result)
 				return false;
 			}
 
-			if (ReadBytes((int)byteLen, out byte[] bytes) == false)
+			if (ReadBytes((int)byteLen, out byte[]? bytes) == false)
 			{
 				result = string.Empty;
 				return false;

Lidgren.Network/NetBuffer.Write.cs

@@ -557,7 +557,7 @@ public int WriteRangedInteger(long min, long max, long value)
 		/// <summary>
 		/// Write a string
 		/// </summary>
-		public void Write(string source)
+		public void Write(string? source)
 		{
 			if (string.IsNullOrEmpty(source))
 			{
@@ -640,7 +640,7 @@ public void Write(NetBuffer buffer)
 		{
 			EnsureBufferSize(m_bitLength + (buffer.LengthBytes * 8));
 
-			Write(buffer.m_data, 0, buffer.LengthBytes);
+			Write(buffer.Data, 0, buffer.LengthBytes);
 
 			// did we write excessive bits?
 			int bitsInLastByte = (buffer.m_bitLength & 7);

Lidgren.Network/NetBuffer.cs

@@ -14,19 +14,21 @@ public partial class NetBuffer
 		private static readonly Dictionary<Type, MethodInfo> s_readMethods;
 		private static readonly Dictionary<Type, MethodInfo> s_writeMethods;
 
-		internal byte[] BufferData => m_data ?? throw new InvalidOperationException($"{nameof(m_data)} is null");
-
 		internal byte[]? m_data;
 		internal int m_bitLength;
 		internal int m_readPosition;
 
 		/// <summary>
-		/// Gets or sets the internal data buffer
+		/// Gets or sets the internal data buffer.
 		/// </summary>
-		public byte[]? Data
+		/// <remarks>
+		/// Throws an <see cref="NetException"/> if internal <see cref="m_data"/> field is null or if set a null value.
+		/// </remarks>
+		/// <exception cref="NetException"/>
+		public byte[] Data
 		{
-			get { return m_data; }
-			set { m_data = value; }
+			get { return NetException.ThrowIfNull(m_data); }
+			set { m_data = NetException.ThrowIfNull(value); }
 		}
 
 		/// <summary>
@@ -71,7 +73,7 @@ public int PositionInBytes
 		{
 			get { return (int)(m_readPosition / 8); }
 		}
-		
+
 		static NetBuffer()
 		{
 			s_readMethods = new Dictionary<Type, MethodInfo>();

Lidgren.Network/NetClient.cs

@@ -90,15 +90,17 @@ public override NetConnection Connect(NetEndPoint remoteEndPoint, NetOutgoingMes
 			{
 				if (m_connections.Count > 0)
 				{
-					throw new InvalidOperationException("Connect attempt failed; Already connected");
+					LogWarning("Connect attempt failed; Already connected");
+					return null!;
 				}
 			}
 
 			lock (m_handshakes)
 			{
 				if (m_handshakes.Count > 0)
 				{
-					throw new InvalidOperationException("Connect attempt failed; Handshake already in progress");
+					LogWarning("Connect attempt failed; Handshake already in progress");
+					return null!;
 				}
 			}
 

Lidgren.Network/NetConnection.Handshake.cs

@@ -310,7 +310,7 @@ internal void ReceivedHandshake(double now, NetMessageType tp, int ptr, int payl
 								appMsg.m_senderConnection = this;
 								appMsg.m_senderEndPoint = this.m_remoteEndPoint;
 								if (m_remoteHailMessage != null)
-									appMsg.Write(m_remoteHailMessage.BufferData, 0, m_remoteHailMessage.LengthBytes);
+									appMsg.Write(m_remoteHailMessage.Data, 0, m_remoteHailMessage.LengthBytes);
 								SetStatus(NetConnectionStatus.RespondedAwaitingApproval, "Awaiting approval");
 								m_peer.ReleaseMessage(appMsg);
 								return;

Lidgren.Network/NetConnection.cs

@@ -113,7 +113,7 @@ internal void ResetTimeout(double now)
 			m_timeoutDeadline = now + m_peerConfiguration.m_connectionTimeout;
 		}
 
-		internal void SetStatus(NetConnectionStatus status, string reason)
+		internal void SetStatus(NetConnectionStatus status, string? reason)
 		{
 			// user or library thread
 

Lidgren.Network/NetException.cs

@@ -18,7 +18,8 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
 using System;
 using System.Diagnostics;
-using System.Runtime.Serialization;
+using System.Diagnostics.CodeAnalysis;
+using System.Runtime.CompilerServices;
 
 namespace Lidgren.Network
 {
@@ -70,5 +71,25 @@ public static void Assert(bool isOk)
 			if (!isOk)
 				throw new NetException();
 		}
+
+		/// <summary>Returns the passed <paramref name="argument"/>, but throws an <see cref="NetException"/> if the <paramref name="argument"/> is null.</summary>
+		/// <param name="argument">The reference type argument to validate as non-null.</param>
+		/// <param name="paramName">The name of the parameter with which <paramref name="argument"/> corresponds.</param>
+#if !DEBUG
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public static T ThrowIfNull<T>(T argument, string? paramName = null)
+		{
+			return argument;
+		}
+#else
+#if NET5_0_OR_GREATER
+		public static T ThrowIfNull<T>([NotNull] T? argument, [CallerArgumentExpression(nameof(argument))] string? paramName = null) where T : class
+#else
+		public static T ThrowIfNull<T>([NotNull] T? argument, string? paramName = null) where T : class
+#endif
+		{
+			return argument ?? throw new NetException($"{paramName ?? "argument"} is null");
+		}
 	}
+#endif
 }

Lidgren.Network/NetOutgoingMessage.cs

@@ -78,7 +78,7 @@ internal int Encode(byte[] intoBuffer, int ptr, int sequenceNumber)
 				int byteLen = NetUtility.BytesToHoldBits(m_bitLength);
 				if (byteLen > 0)
 				{
-					Buffer.BlockCopy(BufferData, 0, intoBuffer, ptr, byteLen);
+					Buffer.BlockCopy(Data, 0, intoBuffer, ptr, byteLen);
 					ptr += byteLen;
 				}
 			}
@@ -102,7 +102,7 @@ internal int Encode(byte[] intoBuffer, int ptr, int sequenceNumber)
 				int byteLen = NetUtility.BytesToHoldBits(m_bitLength);
 				if (byteLen > 0)
 				{
-					Buffer.BlockCopy(BufferData, (int)(m_fragmentChunkNumber * m_fragmentChunkByteSize), intoBuffer, ptr, byteLen);
+					Buffer.BlockCopy(Data, (int)(m_fragmentChunkNumber * m_fragmentChunkByteSize), intoBuffer, ptr, byteLen);
 					ptr += byteLen;
 				}
 			}

Lidgren.Network/NetPeer.Discovery.cs

@@ -19,7 +19,7 @@ public void DiscoverLocalPeers(int serverPort)
 			um.m_messageType = NetMessageType.Discovery;
 			Interlocked.Increment(ref um.m_recyclingCount);
 
-			m_unsentUnconnectedMessages.Enqueue(new NetTuple<NetEndPoint, NetOutgoingMessage>(new NetEndPoint(NetUtility.GetBroadcastAddress() ?? throw new InvalidOperationException(), serverPort), um));
+			m_unsentUnconnectedMessages.Enqueue(new NetTuple<NetEndPoint, NetOutgoingMessage>(new NetEndPoint(NetException.ThrowIfNull(NetUtility.GetBroadcastAddress()), serverPort), um));
 		}
 
 		/// <summary>