2026 Season 3 Update

Samples/DumpVariables_DumpSessionInfo/DumpVariables_DumpSessionInfo.csproj

@@ -15,7 +15,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="10.0.8" />
-    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.0.0" />
+    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.1.0" />
   </ItemGroup>
 
 </Project>

Samples/LocationAndWarnings/LocationAndWarnings.csproj

@@ -15,7 +15,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="10.0.8" />
-    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.0.0" />
+    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.1.0" />
   </ItemGroup>
 
 </Project>

Samples/MinimalExample/MinimalExample.csproj

@@ -15,7 +15,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="10.0.8" />
-    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.0.0" />
+    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.1.0" />
   </ItemGroup>
 
 </Project>

Samples/SpeedRPMGear/SpeedRPMGear.csproj

@@ -17,7 +17,7 @@
     <PackageReference Include="Microsoft.Extensions.Diagnostics" Version="10.0.8" />
     <PackageReference Include="Microsoft.Extensions.Hosting" Version="10.0.8" />
     <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="10.0.8" />
-    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.0.0" />
+    <PackageReference Include="SVappsLAB.iRacingTelemetrySDK" Version="2.1.0" />
   </ItemGroup>
 
 </Project>

Sdk/SVappsLAB.iRacingTelemetrySDK.CodeGen/SVappsLAB.iRacingTelemetrySDK.CodeGen.csproj

@@ -9,7 +9,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="5.0.0" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="5.6.0" PrivateAssets="all" />
   </ItemGroup>
 
   <ItemGroup>

Sdk/SVappsLAB.iRacingTelemetrySDK.EnumsAndFlags/TelemetryClient_Flags.cs

@@ -59,6 +59,7 @@ public enum SessionFlags
         Serviceable = 0x00040000, // car is allowed service (not a flag)
         Furled = 0x00080000,
         Repair = 0x00100000,
+        DqScoringInvalid = 0x00200000, // car is disqualified and scoring is disabled
 
         // start lights
         StartHidden = 0x10000000,

Sdk/SVappsLAB.iRacingTelemetrySDK/DataProviders/DataProviderBase.cs

@@ -1,12 +1,12 @@
 /**
  * Copyright (C) 2024-2026 Scott Velez
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  * http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -120,9 +120,8 @@ public string GetSessionInfoYaml()
             var offSet = header.sessionInfoOffset;
             var maxLen = header.sessionInfoLen;
 
-            var span = new Span<byte>(_dataPtr + offSet, maxLen);
-            var sessInfo = ExtractNullTerminatedString(span, maxLen);
-            return sessInfo;
+            var span = new ReadOnlySpan<byte>(_dataPtr + offSet, maxLen);
+            return SessionInfoDecoder.Decode(span);
         }
 
         public object? GetVarValue(string varName)
@@ -198,6 +197,42 @@ protected void CopyNewTelemetryDataToBuffer(int recNum = 0)
             ros.CopyTo(_telemetryDataBuffer);
         }
 
+        // live telemetry can be overwritten by the sim while we read it. mirror the
+        // official sdk's torn-read detection: 'tickCountBegin' is updated before a
+        // write starts and 'tickCount' after it completes. if the tickCount read
+        // before the copy matches tickCountBegin after, no write was in progress
+        protected bool TryCopyLiveTelemetryDataToBuffer(out int validTickCount)
+        {
+            const int MAX_ATTEMPTS = 2;
+
+            // try a few times to get the data out
+            for (var attempt = 0; attempt < MAX_ATTEMPTS; attempt++)
+            {
+                var header = GetHeader();
+                var bufIndex = header.GetMostRecentBufferIndex();
+                var varBuf = header.GetVarBuf(bufIndex);
+
+                var curTickCount = varBuf.tickCount;
+                Thread.MemoryBarrier();
+
+                var ros = new ReadOnlySpan<byte>(_dataPtr + varBuf.bufOffset, header.bufLen);
+                ros.CopyTo(_telemetryDataBuffer);
+
+                Thread.MemoryBarrier();
+
+                // re-read from shared memory to see if a write was in progress
+                if (curTickCount == GetHeader().GetVarBuf(bufIndex).tickCountBegin)
+                {
+                    validTickCount = curTickCount;
+                    return true;
+                }
+            }
+
+            // the data changed out from under us
+            validTickCount = 0;
+            return false;
+        }
+
         VarHeaderDictionary ReadVarHeaders()
         {
             var ros = new ReadOnlySpan<irsdk_varHeader>(_dataPtr + _header.varHeaderOffset, _header.numVars);

Sdk/SVappsLAB.iRacingTelemetrySDK/DataProviders/LiveDataProvider.cs

@@ -19,7 +19,6 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
-using SVappsLAB.iRacingTelemetrySDK.irSDKDefines;
 
 namespace SVappsLAB.iRacingTelemetrySDK.DataProviders
 {
@@ -58,7 +57,13 @@ public override Task<bool> WaitForDataReady(TimeSpan timeSpan, CancellationToken
 
         internal bool ProcessNewData()
         {
-            var latestTickCount = GetLatestVarBuff().tickCount;
+            // copy new data to the access buffer,
+			// validating data is good and no write was in progress
+            if (!TryCopyLiveTelemetryDataToBuffer(out var latestTickCount))
+            {
+                _logger.LogWarning("data changed while we were reading it. skipping this sample");
+                return false;
+            }
 
             // if we missed any telemetry data, log that it happened
             if (latestTickCount > _lastTickCount)
@@ -67,7 +72,7 @@ internal bool ProcessNewData()
                 if (_lastTickCount != 0 && tickDiff > 0)
                 {
                     _dataDropCount += tickDiff;
-                    _logger.LogWarning("dropped {count} data records. {total} total. last tick: {lastTick}, current tick: {currentTick}", tickDiff, _dataDropCount, _lastTickCount, latestTickCount);
+                    _logger.LogWarning("dropped {count} data records. a total of {total} missed so far. last tick: {lastTick}, current tick: {currentTick}", tickDiff, _dataDropCount, _lastTickCount, latestTickCount);
                 }
             }
 
@@ -78,28 +83,11 @@ internal bool ProcessNewData()
                 _logger.LogDebug("new data is older than our last sample. lost connection?  will resync");
             }
 
-            // copy new data to the access buffer for later reading
-            CopyNewTelemetryDataToBuffer();
             // resync - update our last tick count
             _lastTickCount = latestTickCount;
 
             return true;
         }
-
-        irsdk_varBuf GetLatestVarBuff()
-        {
-            var header = GetHeader();
-
-            var vb = header.varBuf1;
-            if (header.varBuf2.tickCount > vb.tickCount)
-                vb = header.varBuf2;
-            if (header.varBuf3.tickCount > vb.tickCount)
-                vb = header.varBuf3;
-            if (header.varBuf4.tickCount > vb.tickCount)
-                vb = header.varBuf4;
-            return vb;
-
-        }
         public override ValueTask DisposeAsync()
         {
             if (_dataReadyEvent != null)

Sdk/SVappsLAB.iRacingTelemetrySDK/DataProviders/SessionInfoDecoder.cs

@@ -0,0 +1,61 @@
+/**
+ * Copyright (C) 2024-2026 Scott Velez
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+**/
+
+using System;
+using System.Text;
+
+namespace SVappsLAB.iRacingTelemetrySDK.DataProviders
+{
+    // Decodes the raw session-info bytes from the memory-mapped file / IBT file
+    // into a string, depending on the WeekendInfo:Encoding: tag (UTF8).
+    internal static class SessionInfoDecoder
+    {
+        private static readonly byte[] EncodingKey = Encoding.ASCII.GetBytes("Encoding:");
+        private static readonly byte[] Utf8Value = Encoding.ASCII.GetBytes("UTF8");
+
+        /// <summary>
+        /// Decode using the encoding declared by the WeekendInfo:Encoding: tag
+        /// Older session info without "UTF8" use ISO-8859-1
+        /// </summary>
+        public static string Decode(ReadOnlySpan<byte> raw)
+        {
+            // trim at the first null terminator
+            var nullIdx = raw.IndexOf((byte)0);
+            if (nullIdx >= 0)
+                raw = raw.Slice(0, nullIdx);
+
+            if (IsUtf8(raw))
+                return Encoding.UTF8.GetString(raw);
+
+            return Encoding.Latin1.GetString(raw);
+        }
+
+        public static bool IsUtf8(ReadOnlySpan<byte> raw)
+        {
+            var keyIdx = raw.IndexOf(EncodingKey);
+            if (keyIdx < 0)
+                return false;
+
+            // the value is on the same line, immediately after the key
+            var value = raw.Slice(keyIdx + EncodingKey.Length);
+            var eol = value.IndexOf((byte)'\n');
+            if (eol >= 0)
+                value = value.Slice(0, eol);
+
+            return value.IndexOf(Utf8Value) >= 0;
+        }
+    }
+}

Sdk/SVappsLAB.iRacingTelemetrySDK/Models/DriverInfo.cs

@@ -24,6 +24,7 @@ public class DriverInfo
         public int DriverCarIdx { get; set; } // 0
         public int DriverUserID { get; set; } // 22176
         public int PaceCarIdx { get; set; } // -1
+        public int DriverIsAdmin { get; set; } // 0/1 - the player is an admin and can have access to the admin chat commands
         public float DriverHeadPosX { get; set; } // in units of length (mm, m, etc.)
         public float DriverHeadPosY { get; set; } // in units of length (mm, m, etc.)
         public float DriverHeadPosZ { get; set; } // in units of length (mm, m, etc.)
@@ -38,6 +39,9 @@ public class DriverInfo
         public int DriverCarGearNumForward { get; set; } // 6
         public int DriverCarGearNeutral { get; set; } // 1
         public int DriverCarGearReverse { get; set; } // 1
+        public string DriverGearboxType { get; set; } // Sequential/H-Pattern/Automatic/Unknown - transmission type in virtual car
+        public string DriverGearboxControlType { get; set; } // Sequential/H-Pattern/H-Pattern Direct/Automatic/Unknown - physical shifter type player is using
+        public string DriverCarShiftAid { get; set; } // Manual/Antistall/Antistall_Clutch/Antistall_Clutch_Throttle/Automatic - type of shift aids the driver has turned on
         public float DriverCarSLFirstRPM { get; set; } // 5600.000
         public float DriverCarSLShiftRPM { get; set; } // 7200.000
         public float DriverCarSLLastRPM { get; set; } // 7200.000
@@ -51,12 +55,8 @@ public class DriverInfo
         public int DriverSetupPassedTech { get; set; } // 1
         public int DriverIncidentCount { get; set; } // 0
         public float DriverBrakeCurvingFactor { get; set; } // 0.001
-        public int DriverIsAdmin { get; set; } // 0/1 - the player is an admin and can have access to the admin chat commands
-        public string DriverGearboxType { get; set; } // Sequential/H-Pattern/Automatic/Unknown - transmission type in virtual car
-        public string DriverGearboxControlType { get; set; } // Sequential/H-Pattern/H-Pattern Direct/Automatic/Unknown - physical shifter type player is using
-        public string DriverCarShiftAid { get; set; } // Manual/Antistall/Antistall_Clutch/Antistall_Clutch_Throttle/Automatic - type of shift aids the driver has turned on
-        public List<Driver> Drivers { get; set; }
         public List<DriverTire> DriverTires { get; set; }
+        public List<Driver> Drivers { get; set; }
     }
 
     public class Driver

Sdk/SVappsLAB.iRacingTelemetrySDK/Models/WeekendInfo.cs

@@ -1,12 +1,12 @@
 /**
  * Copyright (C) 2024-2026 Scott Velez
- * 
+ *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  * http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -21,6 +21,7 @@ namespace SVappsLAB.iRacingTelemetrySDK
 {
     public class WeekendInfo
     {
+        public string Encoding { get; set; } // "UTF8"
         public string TrackName { get; set; } // spa up
         public int TrackID { get; set; } // 143
         public string TrackLength { get; set; } // 6.93 km (10cm accuracy)
@@ -116,7 +117,7 @@ public class WeekendOptions
         public string IncidentWarningInitialLimit { get; set; } // 'unlimited' or '0'..'n
         public object IncidentWarningSubsequentLimit { get; set; } // 'unlimited' or '0'..'n'
         public string FastRepairsLimit { get; set; } // 'unlimited' or '0'..'n'
-        public string GreenWhiteCheckeredLimit { get; set; } //'unlimited' or '0'..'n' 
+        public string GreenWhiteCheckeredLimit { get; set; } //'unlimited' or '0'..'n'
 
     }
 

Sdk/SVappsLAB.iRacingTelemetrySDK/SVappsLAB.iRacingTelemetrySDK.csproj

@@ -27,9 +27,9 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.Diagnostics.Abstractions" Version="10.0.8" />
-    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.8" />
-    <PackageReference Include="YamlDotNet" Version="17.1.0" />
+    <PackageReference Include="Microsoft.Extensions.Diagnostics.Abstractions" Version="10.0.9" />
+    <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="10.0.9" />
+    <PackageReference Include="YamlDotNet" Version="18.1.0" />
     <ProjectReference Include="..\SVappsLAB.iRacingTelemetrySDK.CodeGen\SVappsLAB.iRacingTelemetrySDK.CodeGen.csproj" OutputItemType="Analyzer" ReferenceOutputAssembly="false" />
     <ProjectReference Include="..\SVappsLAB.iRacingTelemetrySDK.EnumsAndFlags\SVappsLAB.iRacingTelemetrySDK.EnumsAndFlags.csproj" PrivateAssets="all" />
 
@@ -47,7 +47,7 @@
     <PackageTags>iRacing iRacingSDK irsdk IBT Telemetry SDK API</PackageTags>
     <PackageReadmeFile>NUGET.md</PackageReadmeFile>
     <PackageLicenseFile>LICENSE</PackageLicenseFile>
-    <Version>2.0.0</Version>
+    <Version>2.1.0</Version>
     <Authors>Scott Velez</Authors>
     <Company>SVappsLAB</Company>
     <Copyright>Copyright (c) 2026 SVappsLAB</Copyright>