Cleanup | Convert SniLoadHandle to static class

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/LocalDB.netcore.Windows.cs

@@ -56,7 +56,7 @@ private string GetConnectionString(string localDbInstance)
             int result = localDBStartInstanceFunc(localDbInstance, 0, localDBConnectionString, ref sizeOfbuffer);
             if (result != TdsEnums.SNI_SUCCESS)
             {
-                SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBErrorCode, Strings.SNI_ERROR_50);
+                SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBErrorCode, Strings.SNI_ERROR_50);
                 SqlClientEventSource.Log.TrySNITraceEvent(nameof(LocalDB), EventType.ERR, "Unsuccessful 'LocalDBStartInstance' method call with {0} result to start '{1}' localDb instance", args0: result, args1: localDbInstance);
                 localDBConnectionString = null;
             }
@@ -134,15 +134,15 @@ private bool LoadUserInstanceDll()
                     // If there was no DLL path found, then there is an error.
                     if (dllPath == null)
                     {
-                        SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, MapLocalDBErrorStateToCode(registryQueryErrorState), MapLocalDBErrorStateToErrorMessage(registryQueryErrorState));
+                        SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, MapLocalDBErrorStateToCode(registryQueryErrorState), MapLocalDBErrorStateToErrorMessage(registryQueryErrorState));
                         SqlClientEventSource.Log.TrySNITraceEvent(nameof(LocalDB), EventType.ERR, "User instance DLL path is null.");
                         return false;
                     }
 
                     // In case the registry had an empty path for dll
                     if (string.IsNullOrWhiteSpace(dllPath))
                     {
-                        SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBInvalidSqlUserInstanceDllPath, Strings.SNI_ERROR_55);
+                        SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBInvalidSqlUserInstanceDllPath, Strings.SNI_ERROR_55);
                         SqlClientEventSource.Log.TrySNITraceEvent(nameof(LocalDB), EventType.ERR, "User instance DLL path is invalid. DLL path = {0}", dllPath);
                         return false;
                     }
@@ -152,7 +152,7 @@ private bool LoadUserInstanceDll()
 
                     if (libraryHandle.IsInvalid)
                     {
-                        SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBFailedToLoadDll, Strings.SNI_ERROR_56);
+                        SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBFailedToLoadDll, Strings.SNI_ERROR_56);
                         SqlClientEventSource.Log.TrySNITraceEvent(nameof(LocalDB), EventType.ERR, "Library Handle is invalid. Could not load the dll.");
                         libraryHandle.Dispose();
                         return false;
@@ -163,7 +163,7 @@ private bool LoadUserInstanceDll()
 
                     if (_startInstanceHandle == IntPtr.Zero)
                     {
-                        SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBBadRuntime, Strings.SNI_ERROR_57);
+                        SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBBadRuntime, Strings.SNI_ERROR_57);
                         SqlClientEventSource.Log.TrySNITraceEvent(nameof(LocalDB), EventType.ERR, "Was not able to load the PROC from DLL. Bad Runtime.");
                         libraryHandle.Dispose();
                         return false;
@@ -174,7 +174,7 @@ private bool LoadUserInstanceDll()
 
                     if (localDBStartInstanceFunc == null)
                     {
-                        SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBBadRuntime, Strings.SNI_ERROR_57);
+                        SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBBadRuntime, Strings.SNI_ERROR_57);
                         libraryHandle.Dispose();
                         _startInstanceHandle = IntPtr.Zero;
                         return false;

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniCommon.netcore.cs

@@ -216,7 +216,7 @@ internal static uint ReportSNIError(SniProviders provider, uint sniError, Except
         /// <returns></returns>
         internal static uint ReportSNIError(SniError error)
         {
-            SniLoadHandle.SingletonInstance.LastError = error;
+            SniLoadHandle.LastError = error;
             return TdsEnums.SNI_ERROR;
         }
     }

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniError.netcore.cs

@@ -27,6 +27,8 @@ internal class SniError
         public readonly uint lineNumber;
         public readonly Exception exception;
 
+        public static SniError Success { get; } = new(SniProviders.INVALID_PROV, 0, TdsEnums.SNI_SUCCESS, string.Empty);
+
         public SniError(SniProviders provider, int nativeError, uint sniErrorCode, string errorMessage)
         {
             lineNumber = 0;

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniLoadHandle.netcore.cs

@@ -4,65 +4,51 @@
 
 #if NET
 
-using System.Threading;
+using System;
+
+#nullable enable
 
 namespace Microsoft.Data.SqlClient.ManagedSni
 {
     /// <summary>
     /// Global SNI settings and status
     /// </summary>
-    internal class SniLoadHandle
+    internal static class SniLoadHandle
     {
-        public static readonly SniLoadHandle SingletonInstance = new SniLoadHandle();
-
-        public readonly EncryptionOptions _encryptionOption = EncryptionOptions.OFF;
-        public ThreadLocal<SniError> _lastError = new ThreadLocal<SniError>(static () => new SniError(SniProviders.INVALID_PROV, 0, TdsEnums.SNI_SUCCESS, string.Empty));
-
-        private readonly uint _status = TdsEnums.SNI_SUCCESS;
+        [ThreadStatic]
+        private static SniError? s_lastError;
 
         /// <summary>
         /// Last SNI error
         /// </summary>
-        public SniError LastError
+        public static SniError LastError
         {
             get
             {
-                return _lastError.Value;
+                return s_lastError ??= SniError.Success;
             }
 
             set
             {
-                _lastError.Value = value;
+                s_lastError = value;
             }
         }
 
         /// <summary>
         /// SNI library status
         /// </summary>
-        public uint Status
-        {
-            get
-            {
-                return _status;
-            }
-        }
+        public const uint Status = TdsEnums.SNI_SUCCESS;
 
         /// <summary>
         /// Encryption options setting
         /// </summary>
-        public EncryptionOptions Options
-        {
-            get
-            {
-                return _encryptionOption;
-            }
-        }
+        public const EncryptionOptions Options = EncryptionOptions.OFF;
 
         /// <summary>
         /// Verify client encryption possibility
         /// </summary>
         // TODO: by adding support ENCRYPT_NOT_SUP, it could be calculated.
-        public bool ClientOSEncryptionSupport => true;
+        public const bool ClientOSEncryptionSupport = true;
     }
 }
 

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniMarsConnection.netcore.cs

@@ -291,7 +291,7 @@ public void HandleReceiveComplete(SniPacket packet, uint sniErrorCode)
 
                         if (!_sessions.ContainsKey(_currentHeader.sessionId))
                         {
-                            SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.SMUX_PROV, 0, SniCommon.InvalidParameterError, Strings.SNI_ERROR_5);
+                            SniLoadHandle.LastError = new SniError(SniProviders.SMUX_PROV, 0, SniCommon.InvalidParameterError, Strings.SNI_ERROR_5);
                             HandleReceiveError(packet);
                             SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniMarsConnection), EventType.ERR, "Current Header Session Id {0} not found, MARS Session Id {1} will be destroyed, New SNI error created: {2}", args0: _currentHeader?.sessionId, args1: _lowerHandle?.ConnectionId, args2: sniErrorCode);
                             _lowerHandle.Dispose();

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniMarsHandle.netcore.cs

@@ -346,7 +346,7 @@ public void HandleReceiveError(SniPacket packet)
 
                 lock (_receivedPacketQueue)
                 {
-                    _connectionError = SniLoadHandle.SingletonInstance.LastError;
+                    _connectionError = SniLoadHandle.LastError;
                     SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniMarsHandle), EventType.ERR, "MARS Session Id {0}, _connectionError to be handled: {1}", args0: ConnectionId, args1: _connectionError);
                     _packetEvent.Set();
                 }
@@ -520,7 +520,7 @@ public override uint Receive(out SniPacket packet, int timeoutInMilliseconds)
                     SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniMarsHandle), EventType.INFO, "MARS Session Id {0}, _sequenceNumber {1}, _sendHighwater {2}, Waiting for packet event.", args0: ConnectionId, args1: _sequenceNumber, args2: _sendHighwater);
                     if (!_packetEvent.Wait(timeoutInMilliseconds))
                     {
-                        SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.SMUX_PROV, 0, SniCommon.ConnTimeoutError, Strings.SNI_ERROR_11);
+                        SniLoadHandle.LastError = new SniError(SniProviders.SMUX_PROV, 0, SniCommon.ConnTimeoutError, Strings.SNI_ERROR_11);
                         SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniMarsHandle), EventType.INFO, "MARS Session Id {0}, _sequenceNumber {1}, _sendHighwater {2}, _packetEvent wait timed out.", args0: ConnectionId, args1: _sequenceNumber, args2: _sendHighwater);
                         return TdsEnums.SNI_WAIT_TIMEOUT;
                     }

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniPacket.netcore.cs

@@ -285,7 +285,7 @@ private static void ReadFromStreamAsyncContinuation(Task<int> task, object state
             Exception e = task.Exception?.InnerException;
             if (e != null)
             {
-                SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.TCP_PROV, SniCommon.InternalExceptionError, e);
+                SniLoadHandle.LastError = new SniError(SniProviders.TCP_PROV, SniCommon.InternalExceptionError, e);
 #if DEBUG
                 SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniPacket), EventType.ERR, "Connection Id {0}, Internal Exception occurred while reading data: {1}", args0: packet._owner?.ConnectionId, args1: e?.Message);
 #endif
@@ -299,7 +299,7 @@ private static void ReadFromStreamAsyncContinuation(Task<int> task, object state
 #endif
                 if (packet._dataLength == 0)
                 {
-                    SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.TCP_PROV, 0, SniCommon.ConnTerminatedError, Strings.SNI_ERROR_2);
+                    SniLoadHandle.LastError = new SniError(SniProviders.TCP_PROV, 0, SniCommon.ConnTerminatedError, Strings.SNI_ERROR_2);
 #if DEBUG
                     SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniPacket), EventType.ERR, "Connection Id {0}, No data read from stream, connection was terminated.", args0: packet._owner?.ConnectionId);
 #endif
@@ -340,7 +340,7 @@ public async void WriteToStreamAsync(Stream stream, SniAsyncCallback callback, S
             }
             catch (Exception e)
             {
-                SniLoadHandle.SingletonInstance.LastError = new SniError(provider, SniCommon.InternalExceptionError, e);
+                SniLoadHandle.LastError = new SniError(provider, SniCommon.InternalExceptionError, e);
 #if DEBUG
                 SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniPacket), EventType.ERR, "Connection Id {0}, Internal Exception occurred while writing data: {1}", args0: _owner?.ConnectionId, args1: e?.Message);
 #endif

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/ManagedSni/SniProxy.netcore.cs

@@ -107,7 +107,7 @@ internal static SniHandle CreateConnectionHandle(
                 }
                 catch (Exception e)
                 {
-                    SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, SniCommon.ErrorSpnLookup, e);
+                    SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, SniCommon.ErrorSpnLookup, e);
                 }
             }
 
@@ -208,7 +208,7 @@ private static SniTcpHandle CreateTcpHandle(
             string hostName = details.ServerName;
             if (string.IsNullOrWhiteSpace(hostName))
             {
-                SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.TCP_PROV, 0, SniCommon.InvalidConnStringError, Strings.SNI_ERROR_25);
+                SniLoadHandle.LastError = new SniError(SniProviders.TCP_PROV, 0, SniCommon.InvalidConnStringError, Strings.SNI_ERROR_25);
                 return null;
             }
 
@@ -224,7 +224,7 @@ private static SniTcpHandle CreateTcpHandle(
                 }
                 catch (SocketException se)
                 {
-                    SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.TCP_PROV, SniCommon.ErrorLocatingServerInstance, se);
+                    SniLoadHandle.LastError = new SniError(SniProviders.TCP_PROV, SniCommon.ErrorLocatingServerInstance, se);
                     return null;
                 }
             }
@@ -268,7 +268,7 @@ private static SniNpHandle CreateNpHandle(DataSource details, TimeoutTimer timeo
         /// <returns></returns>
         internal SniError GetLastError()
         {
-            return SniLoadHandle.SingletonInstance.LastError;
+            return SniLoadHandle.LastError;
         }
 
         /// <summary>
@@ -448,7 +448,7 @@ internal static string GetLocalDBInstance(string dataSource, out bool error)
             }
             else if (index > 0)
             {
-                SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.ErrorLocatingServerInstance, Strings.SNI_ERROR_26);
+                SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.ErrorLocatingServerInstance, Strings.SNI_ERROR_26);
                 SqlClientEventSource.Log.TrySNITraceEvent(nameof(SniProxy), EventType.ERR, "Incompatible use of prefix with LocalDb: '{0}'", dataSource);
                 error = true;
             }
@@ -467,7 +467,7 @@ internal static string GetLocalDBInstance(string dataSource, out bool error)
                 }
                 else
                 {
-                    SniLoadHandle.SingletonInstance.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBNoInstanceName, Strings.SNI_ERROR_51);
+                    SniLoadHandle.LastError = new SniError(SniProviders.INVALID_PROV, 0, SniCommon.LocalDBNoInstanceName, Strings.SNI_ERROR_51);
                     error = true;
                 }
             }
@@ -594,7 +594,7 @@ private bool InferConnectionDetails()
 
         private void ReportSNIError(SniProviders provider)
         {
-            SniLoadHandle.SingletonInstance.LastError = new SniError(provider, 0, SniCommon.InvalidConnStringError, Strings.SNI_ERROR_25);
+            SniLoadHandle.LastError = new SniError(provider, 0, SniCommon.InvalidConnStringError, Strings.SNI_ERROR_25);
             IsBadDataSource = true;
         }
 

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/TdsParserStateObjectFactory.Unix.cs

@@ -10,14 +10,14 @@ internal sealed class TdsParserStateObjectFactory
     {
         public static readonly TdsParserStateObjectFactory Singleton = new TdsParserStateObjectFactory();
 
-        public EncryptionOptions EncryptionOptions => ManagedSni.SniLoadHandle.SingletonInstance.Options;
+        public EncryptionOptions EncryptionOptions => ManagedSni.SniLoadHandle.Options;
 
-        public uint SNIStatus => ManagedSni.SniLoadHandle.SingletonInstance.Status;
+        public uint SNIStatus => ManagedSni.SniLoadHandle.Status;
 
         /// <summary>
         /// Verify client encryption possibility.
         /// </summary>
-        public bool ClientOSEncryptionSupport => ManagedSni.SniLoadHandle.SingletonInstance.ClientOSEncryptionSupport;
+        public bool ClientOSEncryptionSupport => ManagedSni.SniLoadHandle.ClientOSEncryptionSupport;
 
         public TdsParserStateObject CreateTdsParserStateObject(TdsParser parser)
         {

src/Microsoft.Data.SqlClient/src/Microsoft/Data/SqlClient/TdsParserStateObjectFactory.Windows.cs

@@ -15,14 +15,14 @@ internal sealed class TdsParserStateObjectFactory
 
         public EncryptionOptions EncryptionOptions =>
 #if NET
-            LocalAppContextSwitches.UseManagedNetworking ? ManagedSni.SniLoadHandle.SingletonInstance.Options : SNILoadHandle.SingletonInstance.Options;
+            LocalAppContextSwitches.UseManagedNetworking ? ManagedSni.SniLoadHandle.Options : SNILoadHandle.SingletonInstance.Options;
 #else
             SNILoadHandle.SingletonInstance.Options;
 #endif
 
         public uint SNIStatus =>
 #if NET
-            LocalAppContextSwitches.UseManagedNetworking ? ManagedSni.SniLoadHandle.SingletonInstance.Status : SNILoadHandle.SingletonInstance.Status;
+            LocalAppContextSwitches.UseManagedNetworking ? ManagedSni.SniLoadHandle.Status : SNILoadHandle.SingletonInstance.Status;
 #else
             SNILoadHandle.SingletonInstance.Status;
 #endif
@@ -32,7 +32,7 @@ internal sealed class TdsParserStateObjectFactory
         /// </summary>
         public bool ClientOSEncryptionSupport =>
 #if NET
-            LocalAppContextSwitches.UseManagedNetworking ? ManagedSni.SniLoadHandle.SingletonInstance.ClientOSEncryptionSupport : SNILoadHandle.SingletonInstance.ClientOSEncryptionSupport;
+            LocalAppContextSwitches.UseManagedNetworking ? ManagedSni.SniLoadHandle.ClientOSEncryptionSupport : SNILoadHandle.SingletonInstance.ClientOSEncryptionSupport;
 #else
             SNILoadHandle.SingletonInstance.ClientOSEncryptionSupport;
 #endif