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//------------------------------------------------------------------------------
// <copyright file="SqlInternalConnectionSmi.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
namespace System.Data.SqlClient {
using Microsoft.SqlServer.Server;
using System.Data;
using System.Data.Common;
using System.Diagnostics;
using SysTx = System.Transactions;
sealed internal class SqlInternalConnectionSmi : SqlInternalConnection {
private SmiContext _smiContext;
private SmiConnection _smiConnection;
private SmiEventSink_Default _smiEventSink;
private int _isInUse; // 1 = Connected to open outer connection, 0 = not connected
private SqlInternalTransaction _pendingTransaction; // transaction awaiting event signalling that it is active
private SqlInternalTransaction _currentTransaction; // currently active non-context transaction.
sealed private class EventSink : SmiEventSink_Default {
SqlInternalConnectionSmi _connection;
override internal string ServerVersion {
get {
return SmiContextFactory.Instance.ServerVersion;
}
}
override protected void DispatchMessages(bool ignoreNonFatalMessages) {
// Override this on the Connection event sink, since we can deal
// with info messages here.
SqlException exception = ProcessMessages(false, ignoreNonFatalMessages);
if (null != exception) {
// SQLBUVSTS 225982, query for connection once to avoid race condition between GC (that may collect the connection) and the user thread
SqlConnection connection = _connection.Connection;
if (null != connection && connection.FireInfoMessageEventOnUserErrors) {
connection.OnInfoMessage(new SqlInfoMessageEventArgs(exception));
}
else {
_connection.OnError(exception, false); // we can't really ever break the direct connection, can we?
}
}
}
internal EventSink(SqlInternalConnectionSmi connection) {
Debug.Assert(null != connection, "null connection?");
_connection = connection;
}
internal override void DefaultDatabaseChanged( string databaseName ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.DefaultDatabaseChanged|ADV> %d#, databaseName='%ls'.\n", _connection.ObjectID, databaseName);
}
_connection.CurrentDatabase = databaseName;
}
internal override void TransactionCommitted( long transactionId ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.TransactionCommitted|ADV> %d#, transactionId=0x%I64x.\n", _connection.ObjectID, transactionId);
}
_connection.TransactionEnded(transactionId, TransactionState.Committed);
}
internal override void TransactionDefected( long transactionId ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.TransactionDefected|ADV> %d#, transactionId=0x%I64x.\n", _connection.ObjectID, transactionId);
}
_connection.TransactionEnded(transactionId, TransactionState.Unknown);
}
internal override void TransactionEnlisted( long transactionId ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.TransactionEnlisted|ADV> %d#, transactionId=0x%I64x.\n", _connection.ObjectID, transactionId);
}
_connection.TransactionStarted(transactionId, true); // distributed;
}
internal override void TransactionEnded( long transactionId ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.TransactionEnded|ADV> %d#, transactionId=0x%I64x.\n", _connection.ObjectID, transactionId);
}
_connection.TransactionEndedByServer(transactionId, TransactionState.Unknown);
}
internal override void TransactionRolledBack( long transactionId ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.TransactionRolledBack|ADV> %d#, transactionId=0x%I64x.\n", _connection.ObjectID, transactionId);
}
// Dev11 1066: ensure delegated transaction is rolled back
_connection.TransactionEndedByServer(transactionId, TransactionState.Aborted);
}
internal override void TransactionStarted( long transactionId ) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.EventSink.TransactionStarted|ADV> %d#, transactionId=0x%I64x.\n", _connection.ObjectID, transactionId);
}
_connection.TransactionStarted(transactionId, false); // not distributed;
}
}
internal SqlInternalConnectionSmi(SqlConnectionString connectionOptions, SmiContext smiContext) : base(connectionOptions) {
Debug.Assert(null != smiContext, "null smiContext?");
_smiContext = smiContext;
_smiContext.OutOfScope += new EventHandler(OnOutOfScope);
_smiConnection = _smiContext.ContextConnection;
Debug.Assert(null != _smiConnection, "null SmiContext.ContextConnection?");
_smiEventSink = new EventSink(this);
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.ctor|ADV> %d#, constructed new SMI internal connection\n", ObjectID);
}
}
internal SmiContext InternalContext {
get {
return _smiContext;
}
}
internal SmiConnection SmiConnection {
get {
return _smiConnection;
}
}
internal SmiEventSink CurrentEventSink {
get {
return _smiEventSink;
}
}
override internal SqlInternalTransaction CurrentTransaction {
get {
return _currentTransaction;
}
}
override internal bool IsLockedForBulkCopy {
get {
return false; // no bulk copy in the Direct connection case.
}
}
override internal bool IsShiloh {
get {
return false; // Can't be direct connecting to Shiloh.
}
}
override internal bool IsYukonOrNewer {
get {
return true; // Must be direct connecting to Yukon or newer.
}
}
override internal bool IsKatmaiOrNewer {
get {
return SmiContextFactory.Instance.NegotiatedSmiVersion >= SmiContextFactory.KatmaiVersion;
}
}
override internal SqlInternalTransaction PendingTransaction {
get {
return CurrentTransaction; // there are no differences between pending and current in proc.
}
}
override public string ServerVersion {
get {
return SmiContextFactory.Instance.ServerVersion;
}
}
/// <summary>
/// Get boolean that specifies whether an enlisted transaction can be unbound from
/// the connection when that transaction completes.
/// </summary>
/// <value>
/// True if the connection string property "TransactionBinding" is set to TransactionBindingEnum.ImplicitUnbind;
/// otherwise, false.
/// </value>
protected override bool UnbindOnTransactionCompletion
{
get
{
return ConnectionOptions.TransactionBinding == SqlConnectionString.TransactionBindingEnum.ImplicitUnbind;
}
}
// Workaround to access context transaction without rewriting connection pool & internalconnections properly.
// Context transactions SHOULD be considered enlisted.
// This works for now only because we can't unenlist from the context transaction
// DON'T START USING THIS ANYWHERE EXCEPT IN InternalTransaction and in InternalConnectionSmi!!!
private SysTx.Transaction ContextTransaction
{
get;
set;
}
private SysTx.Transaction InternalEnlistedTransaction
{
get
{
// Workaround to access context transaction without rewriting connection pool & internalconnections properly.
// This SHOULD be a simple wrapper around EnlistedTransaction.
// This works for now only because we can't unenlist from the context transaction
SysTx.Transaction tx = EnlistedTransaction;
if (null == tx)
{
tx = ContextTransaction;
}
return tx;
}
}
override protected void Activate(SysTx.Transaction transaction)
{
Debug.Assert(false, "Activating an internal SMI connection?"); // we should never be activating, because that would indicate we're being pooled.
}
internal void Activate() {
int wasInUse = System.Threading.Interlocked.Exchange(ref _isInUse, 1);
if (0 != wasInUse) {
throw SQL.ContextConnectionIsInUse();
}
CurrentDatabase = _smiConnection.GetCurrentDatabase(_smiEventSink);
_smiEventSink.ProcessMessagesAndThrow();
}
internal void AutomaticEnlistment() {
SysTx.Transaction currentSystemTransaction = ADP.GetCurrentTransaction(); // NOTE: Must be first to ensure _smiContext.ContextTransaction is set!
SysTx.Transaction contextTransaction = _smiContext.ContextTransaction; // returns the transaction that was handed to SysTx that wraps the ContextTransactionId.
long contextTransactionId = _smiContext.ContextTransactionId;
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.AutomaticEnlistment|ADV> %d#, contextTransactionId=0x%I64x, contextTransaction=%d#, currentSystemTransaction=%d#.\n",
base.ObjectID,
contextTransactionId,
(null != contextTransaction) ? contextTransaction.GetHashCode() : 0,
(null != currentSystemTransaction) ? currentSystemTransaction.GetHashCode() : 0);
}
if (SqlInternalTransaction.NullTransactionId != contextTransactionId) {
if (null != currentSystemTransaction && contextTransaction != currentSystemTransaction) {
throw SQL.NestedTransactionScopesNotSupported(); // can't use TransactionScope(RequiresNew) inside a Sql Transaction.
}
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.AutomaticEnlistment|ADV> %d#, using context transaction with transactionId=0x%I64x\n", base.ObjectID, contextTransactionId);
}
_currentTransaction = new SqlInternalTransaction(this, TransactionType.Context, null, contextTransactionId);
ContextTransaction = contextTransaction;
}
else if (null == currentSystemTransaction) {
_currentTransaction = null; // there really isn't a transaction.
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.AutomaticEnlistment|ADV> %d#, no transaction.\n", base.ObjectID);
}
}
else {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.AutomaticEnlistment|ADV> %d#, using current System.Transaction.\n", base.ObjectID);
}
base.Enlist(currentSystemTransaction);
}
}
override protected void ChangeDatabaseInternal(string database) {
_smiConnection.SetCurrentDatabase(database, _smiEventSink);
_smiEventSink.ProcessMessagesAndThrow();
}
override protected void InternalDeactivate() {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.Deactivate|ADV> %d#, Deactivating.\n", base.ObjectID);
}
// When we put this to bed, we should not hold on to the transaction
// or any activity (commit/rollback) may cause it to stop responding.
if (!IsNonPoolableTransactionRoot) {
base.Enlist(null);
}
if (null != _currentTransaction) {
if (_currentTransaction.IsContext) {
_currentTransaction = null;
}
else if (_currentTransaction.IsLocal) {
_currentTransaction.CloseFromConnection();
}
}
ContextTransaction = null;
_isInUse = 0; // don't need compare-exchange.
}
override internal void DelegatedTransactionEnded() {
base.DelegatedTransactionEnded();
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.DelegatedTransactionEnded|ADV> %d#, cleaning up after Delegated Transaction Completion\n", base.ObjectID);
}
_currentTransaction = null; // clean up our current transaction too
}
override internal void DisconnectTransaction(SqlInternalTransaction internalTransaction) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.DisconnectTransaction|ADV> %d#, Disconnecting Transaction %d#.\n", base.ObjectID, internalTransaction.ObjectID);
}
// VSTS 215465/15029: allow _currentTransaction to be null - it can be cleared before by server's callback
Debug.Assert(_currentTransaction == null || _currentTransaction == internalTransaction, "disconnecting different transaction");
if (_currentTransaction != null && _currentTransaction == internalTransaction) {
_currentTransaction = null;
}
}
override public void Dispose() {
_smiContext.OutOfScope -= new EventHandler(OnOutOfScope);
base.Dispose();
}
override internal void ExecuteTransaction(
TransactionRequest transactionRequest,
string transactionName,
IsolationLevel iso,
SqlInternalTransaction internalTransaction,
bool isDelegateControlRequest) {
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.ExecuteTransaction|ADV> %d#, transactionRequest=%ls, transactionName='%ls', isolationLevel=%ls, internalTransaction=#%d transactionId=0x%I64x.\n",
base.ObjectID,
transactionRequest.ToString(),
(null != transactionName) ? transactionName : "null",
iso.ToString(),
(null != internalTransaction) ? internalTransaction.ObjectID : 0,
(null != internalTransaction) ? internalTransaction.TransactionId : SqlInternalTransaction.NullTransactionId
);
}
switch (transactionRequest) {
case TransactionRequest.Begin:
try {
_pendingTransaction = internalTransaction; // store this for the time being.
_smiConnection.BeginTransaction(transactionName, iso, _smiEventSink);
}
finally {
_pendingTransaction = null;
}
Debug.Assert(_smiEventSink.HasMessages || null != _currentTransaction, "begin transaction without TransactionStarted event?");
break;
case TransactionRequest.Commit:
Debug.Assert(null != _currentTransaction, "commit transaction without TransactionStarted event?");
_smiConnection.CommitTransaction(_currentTransaction.TransactionId, _smiEventSink);
break;
case TransactionRequest.Promote:
Debug.Assert(null != _currentTransaction, "promote transaction without TransactionStarted event?");
PromotedDTCToken = _smiConnection.PromoteTransaction(_currentTransaction.TransactionId, _smiEventSink);
break;
case TransactionRequest.Rollback:
case TransactionRequest.IfRollback:
Debug.Assert(null != _currentTransaction, "rollback/ifrollback transaction without TransactionStarted event?");
_smiConnection.RollbackTransaction(_currentTransaction.TransactionId, transactionName, _smiEventSink);
break;
case TransactionRequest.Save:
Debug.Assert(null != _currentTransaction, "save transaction without TransactionStarted event?");
_smiConnection.CreateTransactionSavePoint(_currentTransaction.TransactionId, transactionName, _smiEventSink);
break;
default:
Debug.Assert (false, "unhandled case for TransactionRequest");
break;
}
_smiEventSink.ProcessMessagesAndThrow();
}
override protected byte[] GetDTCAddress() {
byte[] whereAbouts = _smiConnection.GetDTCAddress(_smiEventSink); // might want to store this on the SmiLink because it doesn't change, but we want to be compatible with TDS which doesn't have a link yet.
_smiEventSink.ProcessMessagesAndThrow();
if (Bid.AdvancedOn) {
if (null != whereAbouts) {
Bid.TraceBin("<sc.SqlInternalConnectionSmi.GetDTCAddress|ADV> whereAbouts", whereAbouts, (UInt16)whereAbouts.Length);
}
else {
Bid.Trace("<sc.SqlInternalConnectionSmi.GetDTCAddress|ADV> whereAbouts=null\n");
}
}
return whereAbouts;
}
internal void GetCurrentTransactionPair(out long transactionId, out SysTx.Transaction transaction) {
// SQLBU 214740: Transaction state could change between obtaining tranid and transaction
// due to background SqlDelegatedTransaction processing. Lock the connection to prevent that.
lock (this) {
transactionId = (null != CurrentTransaction) ? CurrentTransaction.TransactionId : 0;
transaction = null;
if (0 != transactionId) {
transaction = InternalEnlistedTransaction;
}
}
}
private void OnOutOfScope(object s, EventArgs e) {
// Called whenever the context goes out of scope, we need to make
// sure that we close the connection, or the next person that uses
// the context may appear to have the connection in use.
if (Bid.AdvancedOn) {
Bid.Trace("<sc.SqlInternalConnectionSmi.OutOfScope|ADV> %d# context is out of scope\n", base.ObjectID);
}
//
DelegatedTransaction = null; // we don't want to hold this over to the next usage; it will automatically be reused as the context transaction...
DbConnection owningObject = (DbConnection)Owner;
try {
if (null != owningObject && 1 == _isInUse) {
// SQLBU 369953
// for various reasons, the owning object may no longer be connection to this
// so call close on the owner, rather than trying to bypass to use internal close logic.
owningObject.Close();
}
}
finally {
// Now make sure this object is not left in an in-use state
// this is safe, because no user code should be accessing the connection by this time
ContextTransaction = null;
_isInUse = 0;
}
}
override protected void PropagateTransactionCookie(byte[] transactionCookie) {
if (Bid.AdvancedOn) {
if (null != transactionCookie) {
Bid.TraceBin("<sc.SqlInternalConnectionSmi.PropagateTransactionCookie|ADV> transactionCookie", transactionCookie, (UInt16)transactionCookie.Length);
}
else {
Bid.Trace("<sc.SqlInternalConnectionSmi.PropagateTransactionCookie|ADV> null\n");
}
}
// Propagate the transaction cookie to the server
_smiConnection.EnlistTransaction(transactionCookie, _smiEventSink);
_smiEventSink.ProcessMessagesAndThrow();
}
private void TransactionEndedByServer(long transactionId, TransactionState transactionState) {
// Some extra steps required when the server initiates the ending of a transaction unilaterally
// as opposed to the client initiating it.
// Basically, we have to make the delegated transaction (if there is one) aware of the situation.
SqlDelegatedTransaction delegatedTransaction = DelegatedTransaction;
if (null != delegatedTransaction) {
delegatedTransaction.Transaction.Rollback(); // just to make sure...
DelegatedTransaction = null; // He's dead, Jim.
}
// Now handle the standard transaction-ended stuff.
TransactionEnded(transactionId, transactionState);
}
private void TransactionEnded(long transactionId, TransactionState transactionState) {
// When we get notification of a completed transaction
// we null out the current transaction.
if (null != _currentTransaction) {
#if DEBUG
// Check null for case where Begin and Rollback obtained in the same message.
if (0 != _currentTransaction.TransactionId) {
Debug.Assert(_currentTransaction.TransactionId == transactionId, "transaction id's are not equal!");
}
#endif
_currentTransaction.Completed(transactionState);
_currentTransaction = null;
}
}
private void TransactionStarted(long transactionId, bool isDistributed) {
// When we get notification from the server of a new
// transaction, we move any pending transaction over to
// the current transaction, then we store the token in it.
// if there isn't a pending transaction, then it's either
// a TSQL transaction or a distributed transaction.
Debug.Assert(null == _currentTransaction, "non-null current transaction with an env change");
_currentTransaction = _pendingTransaction;
_pendingTransaction = null;
if (null != _currentTransaction) {
_currentTransaction.TransactionId = transactionId; // this is defined as a ULongLong in the server and in the TDS Spec.
}
else {
TransactionType transactionType = (isDistributed) ? TransactionType.Distributed : TransactionType.LocalFromTSQL;
_currentTransaction = new SqlInternalTransaction(this, transactionType, null, transactionId);
}
_currentTransaction.Activate(); // SQLBUDT #376531 -- ensure this is activated to prevent asserts later.
}
override internal void ValidateConnectionForExecute(SqlCommand command) {
SqlDataReader reader = FindLiveReader(null);
if (null != reader) {
// if MARS is on, then a datareader associated with the command exists
// or if MARS is off, then a datareader exists
throw ADP.OpenReaderExists(); // MDAC 66411
}
}
}
}
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