Read/Write variable sized Int32/Int64 bug fixed; very large numbers were decoded incorrectly

Lidgren.Network/NetIncomingMessage.Read.cs

@@ -329,9 +329,6 @@ namespace Lidgren.Network
 			int num2 = 0;
 			while (true)
 			{
-				if (num2 == 0x23)
-					throw new FormatException("Bad 7-bit encoded integer");
-
 				byte num3 = this.ReadByte();
 				num1 |= (num3 & 0x7f) << num2;
 				num2 += 7;
@@ -345,22 +342,8 @@ namespace Lidgren.Network
 		/// </summary>
 		public int ReadVariableInt32()
 		{
-			int num1 = 0;
+			uint n = ReadVariableUInt32();
-			int num2 = 0;
+			return (int)(n >> 1) ^ -(int)(n & 1); // decode zigzag
-			while (true)
-			{
-				if (num2 == 0x23)
-					throw new FormatException("Bad 7-bit encoded integer");
-
-				byte num3 = this.ReadByte();
-				num1 |= (num3 & 0x7f) << (num2 & 0x1f);
-				num2 += 7;
-				if ((num3 & 0x80) == 0)
-				{
-					int sign = (num1 << 31) >> 31;
-					return sign ^ (num1 >> 1);
-				}
-			}
 		}
 
 		/// <summary>
@@ -368,22 +351,8 @@ namespace Lidgren.Network
 		/// </summary>
 		public Int64 ReadVariableInt64()
 		{
-			Int64 num1 = 0;
+			UInt64 n = ReadVariableUInt64();
-			int num2 = 0;
+			return (Int64)(n >> 1) ^ -(long)(n & 1); // decode zigzag
-			while (true)
-			{
-				if (num2 == 0x23)
-					throw new FormatException("Bad 7-bit encoded integer");
-
-				byte num3 = this.ReadByte();
-				num1 |= (Int64)((Int64)(num3 & 0x7f) << (num2 & 0x1f));
-				num2 += 7;
-				if ((num3 & 0x80) == 0)
-				{
-					Int64 sign = (num1 << 63) >> 63;
-					return sign ^ (num1 >> 1);
-				}
-			}
 		}
 
 		/// <summary>
@@ -396,8 +365,8 @@ namespace Lidgren.Network
 			int num2 = 0;
 			while (true)
 			{
-				if (num2 == 0x23)
+				//if (num2 == 0x23)
-					throw new FormatException("Bad 7-bit encoded integer");
+				//	throw new FormatException("Bad 7-bit encoded integer");
 
 				byte num3 = this.ReadByte();
 				num1 |= ((UInt64)num3 & 0x7f) << num2;
@@ -511,6 +480,14 @@ namespace Lidgren.Network
 			m_readPosition = ((m_readPosition + 7) >> 3) * 8;
 		}
 
+		/// <summary>
+		/// Pads data with enough bits to reach a full byte. Decreases cpu usage for subsequent byte writes.
+		/// </summary>
+		public void ReadPadBits()
+		{
+			m_readPosition = ((m_readPosition + 7) >> 3) * 8;
+		}
+
 		/// <summary>
 		/// Pads data with the specified number of bits.
 		/// </summary>

Lidgren.Network/NetOutgoingMessage.Write.cs

@@ -393,7 +393,7 @@ namespace Lidgren.Network
 		//
 
 		/// <summary>
-		/// Write Base128 encoded variable sized unsigned integer
+		/// Write Base128 encoded variable sized unsigned integer of up to 32 bits
 		/// </summary>
 		/// <returns>number of bytes written</returns>
 		[CLSCompliant(false)]
@@ -412,43 +412,27 @@ namespace Lidgren.Network
 		}
 
 		/// <summary>
-		/// Write Base128 encoded variable sized signed integer
+		/// Write Base128 encoded variable sized signed integer of up to 32 bits
 		/// </summary>
 		/// <returns>number of bytes written</returns>
 		public int WriteVariableInt32(int value)
 		{
-			int retval = 1;
+			uint zigzag = (uint)(value << 1) ^ (uint)(value >> 31);
-			uint num1 = (uint)((value << 1) ^ (value >> 31));
+			return WriteVariableUInt32(zigzag);
-			while (num1 >= 0x80)
-			{
-				this.Write((byte)(num1 | 0x80));
-				num1 = num1 >> 7;
-				retval++;
-			}
-			this.Write((byte)num1);
-			return retval;
 		}
 
 		/// <summary>
-		/// Write Base128 encoded variable sized signed integer
+		/// Write Base128 encoded variable sized signed integer of up to 64 bits
 		/// </summary>
 		/// <returns>number of bytes written</returns>
 		public int WriteVariableInt64(Int64 value)
 		{
-			int retval = 1;
+			ulong zigzag = (ulong)(value << 1) ^ (ulong)(value >> 63);
-			UInt64 num1 = (UInt64)((value << 1) ^ (value >> 31));
+			return WriteVariableUInt64(zigzag);
-			while (num1 >= 0x80)
-			{
-				this.Write((byte)(num1 | 0x80));
-				num1 = num1 >> 7;
-				retval++;
-			}
-			this.Write((byte)num1);
-			return retval;
 		}
 
 		/// <summary>
-		/// Write Base128 encoded variable sized unsigned integer
+		/// Write Base128 encoded variable sized unsigned integer of up to 64 bits
 		/// </summary>
 		/// <returns>number of bytes written</returns>
 		[CLSCompliant(false)]

UnitTests/ReadWriteTests.cs

@@ -9,6 +9,30 @@ namespace UnitTests
 {
 	public static class ReadWriteTests
 	{
+		public static string ToBinaryString(ulong value, int bits, bool includeSpaces)
+		{
+			int numSpaces = Math.Max(0, (bits / 8) - 1);
+			if (includeSpaces == false)
+				numSpaces = 0;
+
+			StringBuilder bdr = new StringBuilder(bits + numSpaces);
+			for (int i = 0; i < bits + numSpaces; i++)
+				bdr.Append(' ');
+
+			for (int i = 0; i < bits; i++)
+			{
+				ulong shifted = (ulong)(value >> i);
+				bool isSet = ((shifted & 1) != 0);
+
+				int pos = bits - 1 - i;
+				if (includeSpaces)
+					pos += Math.Max(0, (pos / 8));
+
+				bdr[pos] = (isSet ? '1' : '0');
+			}
+			return bdr.ToString();
+		}
+
 		public static void Run(NetPeer peer)
 		{
 			NetOutgoingMessage msg = peer.CreateMessage();
@@ -26,6 +50,7 @@ namespace UnitTests
 			int bcnt = 0;
 
 			msg.Write(45.0f);
+			msg.WriteVariableInt32(2115998022);
 			msg.Write(46.0);
 			bcnt += msg.WriteVariableInt32(-47);
 			msg.WriteVariableInt32(470000);
@@ -56,13 +81,14 @@ namespace UnitTests
 			inc.SkipPadBits();
 
 			bdr.Append(inc.ReadSingle());
+			bdr.Append(inc.ReadVariableInt32());
 			bdr.Append(inc.ReadDouble());
 			bdr.Append(inc.ReadVariableInt32());
 			bdr.Append(inc.ReadVariableInt32());
 			bdr.Append(inc.ReadVariableUInt32());
 			bdr.Append(inc.ReadVariableInt64());
 
-			if (bdr.ToString().Equals("False-342duke of earl4344True4546-4747000048-49"))
+			if (bdr.ToString().Equals("False-342duke of earl4344True45211599802246-4747000048-49"))
 				Console.WriteLine("Read/write tests OK");
 			else
 				throw new NetException("Read/write tests FAILED!");