// assumes that the current position is at the start of an altrow! internal bool TryGetAltRowId(TdsParserStateObject stateObj, out int id) { byte token; if (!stateObj.TryReadByte(out token)) { // skip over ALTROW token id = 0; return false; } Debug.Assert((token == TdsEnums.SQLALTROW), ""); // Start a fresh row - disable NBC since Alt Rows are never compressed if (!stateObj.TryStartNewRow(isNullCompressed: false)) { id = 0; return false; } ushort shortId; if (!stateObj.TryReadUInt16(out shortId)) { id = 0; return false; } id = shortId; return true; }
// Main parse loop for the top-level tds tokens, calls back into the I*Handler interfaces internal bool TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, out bool dataReady) { Debug.Assert((SniContext.Undefined != stateObj.SniContext) && // SniContext must not be Undefined ((stateObj._attentionSent) || ((SniContext.Snix_Execute != stateObj.SniContext) && (SniContext.Snix_SendRows != stateObj.SniContext))), // SniContext should not be Execute or SendRows unless attention was sent (and, therefore, we are looking for an ACK) String.Format("Unexpected SniContext on call to TryRun; SniContext={0}", stateObj.SniContext)); if (TdsParserState.Broken == State || TdsParserState.Closed == State) { dataReady = true; return true; // Just in case this is called in a loop, expecting data to be returned. } dataReady = false; do { // If there is data ready, but we didn't exit the loop, then something is wrong Debug.Assert(!dataReady, "dataReady not expected - did we forget to skip the row?"); if (stateObj._internalTimeout) { runBehavior = RunBehavior.Attention; } if (TdsParserState.Broken == State || TdsParserState.Closed == State) break; // jump out of the loop if the state is already broken or closed. if (!stateObj._accumulateInfoEvents && (stateObj._pendingInfoEvents != null)) { if (RunBehavior.Clean != (RunBehavior.Clean & runBehavior)) { SqlConnection connection = null; if (_connHandler != null) connection = _connHandler.Connection; // SqlInternalConnection holds the user connection object as a weak ref // We are omitting checks for error.Class in the code below (see processing of INFO) since we know (and assert) that error class // error.Class < TdsEnums.MIN_ERROR_CLASS for info message. // Also we know that TdsEnums.MIN_ERROR_CLASS<TdsEnums.MAX_USER_CORRECTABLE_ERROR_CLASS if ((connection != null) && connection.FireInfoMessageEventOnUserErrors) { foreach (SqlError error in stateObj._pendingInfoEvents) FireInfoMessageEvent(connection, stateObj, error); } else foreach (SqlError error in stateObj._pendingInfoEvents) stateObj.AddWarning(error); } stateObj._pendingInfoEvents = null; } byte token; if (!stateObj.TryReadByte(out token)) { return false; } if (!IsValidTdsToken(token)) { Debug.Assert(false, String.Format((IFormatProvider)null, "unexpected token; token = {0,-2:X2}", token)); _state = TdsParserState.Broken; _connHandler.BreakConnection(); throw SQL.ParsingError(); } int tokenLength; if (!TryGetTokenLength(token, stateObj, out tokenLength)) { return false; } switch (token) { case TdsEnums.SQLERROR: case TdsEnums.SQLINFO: { if (token == TdsEnums.SQLERROR) { stateObj._errorTokenReceived = true; // Keep track of the fact error token was received - for Done processing. } SqlError error; if (!TryProcessError(token, stateObj, out error)) { return false; } if (token == TdsEnums.SQLINFO && stateObj._accumulateInfoEvents) { Debug.Assert(error.Class < TdsEnums.MIN_ERROR_CLASS, "INFO with class > TdsEnums.MIN_ERROR_CLASS"); if (stateObj._pendingInfoEvents == null) stateObj._pendingInfoEvents = new List<SqlError>(); stateObj._pendingInfoEvents.Add(error); stateObj._syncOverAsync = true; break; } if (RunBehavior.Clean != (RunBehavior.Clean & runBehavior)) { // If FireInfoMessageEventOnUserErrors is true, we have to fire event without waiting. // Otherwise we can go ahead and add it to errors/warnings collection. SqlConnection connection = null; if (_connHandler != null) connection = _connHandler.Connection; // SqlInternalConnection holds the user connection object as a weak ref if ((connection != null) && (connection.FireInfoMessageEventOnUserErrors == true) && (error.Class <= TdsEnums.MAX_USER_CORRECTABLE_ERROR_CLASS)) { // Fire SqlInfoMessage here FireInfoMessageEvent(connection, stateObj, error); } else { // insert error/info into the appropriate exception - warning if info, exception if error if (error.Class < TdsEnums.MIN_ERROR_CLASS) { stateObj.AddWarning(error); } else if (error.Class < TdsEnums.FATAL_ERROR_CLASS) { // Continue results processing for all non-fatal errors (<20) stateObj.AddError(error); // Add it to collection - but do NOT change run behavior UNLESS // we are in an ExecuteReader call - at which time we will be throwing // anyways so we need to consume all errors. This is not the case // if we have already given out a reader. If we have already given out // a reader we need to throw the error but not halt further processing. We used to // halt processing. if (null != dataStream) { if (!dataStream.IsInitialized) { runBehavior = RunBehavior.UntilDone; } } } else { stateObj.AddError(error); // Else we have a fatal error and we need to change the behavior // since we want the complete error information in the exception. // Besides - no further results will be received. runBehavior = RunBehavior.UntilDone; } } } else if (error.Class >= TdsEnums.FATAL_ERROR_CLASS) { stateObj.AddError(error); } break; } case TdsEnums.SQLCOLINFO: { if (null != dataStream) { _SqlMetaDataSet metaDataSet; if (!TryProcessColInfo(dataStream.MetaData, dataStream, stateObj, out metaDataSet)) { return false; } if (!dataStream.TrySetMetaData(metaDataSet, false)) { return false; } dataStream.BrowseModeInfoConsumed = true; } else { // no dataStream if (!stateObj.TrySkipBytes(tokenLength)) { return false; } } break; } case TdsEnums.SQLDONE: case TdsEnums.SQLDONEPROC: case TdsEnums.SQLDONEINPROC: { // RunBehavior can be modified if (!TryProcessDone(cmdHandler, dataStream, ref runBehavior, stateObj)) { return false; } if ((token == TdsEnums.SQLDONEPROC) && (cmdHandler != null)) { cmdHandler.OnDoneProc(); } break; } case TdsEnums.SQLORDER: { // don't do anything with the order token so read off the pipe if (!stateObj.TrySkipBytes(tokenLength)) { return false; } break; } case TdsEnums.SQLALTMETADATA: { stateObj.CloneCleanupAltMetaDataSetArray(); if (stateObj._cleanupAltMetaDataSetArray == null) { // create object on demand (lazy creation) stateObj._cleanupAltMetaDataSetArray = new _SqlMetaDataSetCollection(); } _SqlMetaDataSet cleanupAltMetaDataSet; if (!TryProcessAltMetaData(tokenLength, stateObj, out cleanupAltMetaDataSet)) { return false; } stateObj._cleanupAltMetaDataSetArray.SetAltMetaData(cleanupAltMetaDataSet); if (null != dataStream) { byte metadataConsumedByte; if (!stateObj.TryPeekByte(out metadataConsumedByte)) { return false; } if (!dataStream.TrySetAltMetaDataSet(cleanupAltMetaDataSet, (TdsEnums.SQLALTMETADATA != metadataConsumedByte))) { return false; } } break; } case TdsEnums.SQLALTROW: { if (!stateObj.TryStartNewRow(isNullCompressed: false)) { // altrows are not currently null compressed return false; } // read will call run until dataReady. Must not read any data if returnimmetiately set if (RunBehavior.ReturnImmediately != (RunBehavior.ReturnImmediately & runBehavior)) { ushort altRowId; if (!stateObj.TryReadUInt16(out altRowId)) { // get altRowId return false; } if (!TrySkipRow(stateObj._cleanupAltMetaDataSetArray.GetAltMetaData(altRowId), stateObj)) { // skip altRow return false; } } else { dataReady = true; } break; } case TdsEnums.SQLENVCHANGE: { // ENVCHANGE must be processed synchronously (since it can modify the state of many objects) stateObj._syncOverAsync = true; SqlEnvChange[] env; if (!TryProcessEnvChange(tokenLength, stateObj, out env)) { return false; } for (int ii = 0; ii < env.Length; ii++) { if (env[ii] != null && !this.Connection.IgnoreEnvChange) { switch (env[ii].type) { case TdsEnums.ENV_BEGINTRAN: // 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 = env[ii].newLongValue; // this is defined as a ULongLong in the server and in the TDS Spec. } else { TransactionType transactionType = TransactionType.LocalFromTSQL; _currentTransaction = new SqlInternalTransaction(_connHandler, transactionType, null, env[ii].newLongValue); } if (null != _statistics && !_statisticsIsInTransaction) { _statistics.SafeIncrement(ref _statistics._transactions); } _statisticsIsInTransaction = true; break; case TdsEnums.ENV_COMMITTRAN: // SQLHOT 483 // Must clear the retain id if the server-side transaction ends by anything other // than rollback. goto case TdsEnums.ENV_ROLLBACKTRAN; case TdsEnums.ENV_ROLLBACKTRAN: // 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 (SqlInternalTransaction.NullTransactionId != _currentTransaction.TransactionId) { Debug.Assert(_currentTransaction.TransactionId != env[ii].newLongValue, "transaction id's are not equal!"); } #endif if (TdsEnums.ENV_COMMITTRAN == env[ii].type) { _currentTransaction.Completed(TransactionState.Committed); } else if (TdsEnums.ENV_ROLLBACKTRAN == env[ii].type) { // Hold onto transaction id if distributed tran is rolled back. This must // be sent to the server on subsequent executions even though the transaction // is considered to be rolled back. _currentTransaction.Completed(TransactionState.Aborted); } else { _currentTransaction.Completed(TransactionState.Unknown); } _currentTransaction = null; } _statisticsIsInTransaction = false; break; case TdsEnums.ENV_ENLISTDTC: case TdsEnums.ENV_DEFECTDTC: case TdsEnums.ENV_TRANSACTIONENDED: Debug.Assert(false, "Should have thrown if DTC token encountered"); break; default: _connHandler.OnEnvChange(env[ii]); break; } } } break; } case TdsEnums.SQLLOGINACK: { SqlLoginAck ack; if (!TryProcessLoginAck(stateObj, out ack)) { return false; } _connHandler.OnLoginAck(ack); break; } case TdsEnums.SQLFEATUREEXTACK: { if (!TryProcessFeatureExtAck(stateObj)) { return false; } break; } case TdsEnums.SQLSESSIONSTATE: { if (!TryProcessSessionState(stateObj, tokenLength, _connHandler._currentSessionData)) { return false; } break; } case TdsEnums.SQLCOLMETADATA: { if (tokenLength != TdsEnums.VARNULL) { _SqlMetaDataSet metadata; if (!TryProcessMetaData(tokenLength, stateObj, out metadata)) { return false; } stateObj._cleanupMetaData = metadata; } else { if (cmdHandler != null) { stateObj._cleanupMetaData = cmdHandler.MetaData; } } if (null != dataStream) { byte peekedToken; if (!stateObj.TryPeekByte(out peekedToken)) { // temporarily cache next byte return false; } if (!dataStream.TrySetMetaData(stateObj._cleanupMetaData, (TdsEnums.SQLTABNAME == peekedToken || TdsEnums.SQLCOLINFO == peekedToken))) { return false; } } else if (null != bulkCopyHandler) { bulkCopyHandler.SetMetaData(stateObj._cleanupMetaData); } break; } case TdsEnums.SQLROW: case TdsEnums.SQLNBCROW: { Debug.Assert(stateObj._cleanupMetaData != null, "Reading a row, but the metadata is null"); if (token == TdsEnums.SQLNBCROW) { if (!stateObj.TryStartNewRow(isNullCompressed: true, nullBitmapColumnsCount: stateObj._cleanupMetaData.Length)) { return false; } } else { if (!stateObj.TryStartNewRow(isNullCompressed: false)) { return false; } } if (null != bulkCopyHandler) { if (!TryProcessRow(stateObj._cleanupMetaData, bulkCopyHandler.CreateRowBuffer(), bulkCopyHandler.CreateIndexMap(), stateObj)) { return false; } } else if (RunBehavior.ReturnImmediately != (RunBehavior.ReturnImmediately & runBehavior)) { if (!TrySkipRow(stateObj._cleanupMetaData, stateObj)) { // skip rows return false; } } else { dataReady = true; } if (_statistics != null) { _statistics.WaitForDoneAfterRow = true; } break; } case TdsEnums.SQLRETURNSTATUS: int status; if (!stateObj.TryReadInt32(out status)) { return false; } if (cmdHandler != null) { cmdHandler.OnReturnStatus(status); } break; case TdsEnums.SQLRETURNVALUE: { SqlReturnValue returnValue; if (!TryProcessReturnValue(tokenLength, stateObj, out returnValue)) { return false; } if (cmdHandler != null) { cmdHandler.OnReturnValue(returnValue); } break; } case TdsEnums.SQLSSPI: { // token length is length of SSPI data - call ProcessSSPI with it Debug.Assert(stateObj._syncOverAsync, "ProcessSSPI does not support retry, do not attempt asynchronously"); stateObj._syncOverAsync = true; ProcessSSPI(tokenLength); break; } case TdsEnums.SQLTABNAME: { { if (!stateObj.TrySkipBytes(tokenLength)) { return false; } } break; } default: Debug.Assert(false, "Unhandled token: " + token.ToString(CultureInfo.InvariantCulture)); break; } Debug.Assert(stateObj._pendingData || !dataReady, "dataReady is set, but there is no pending data"); } // Loop while data pending & runbehavior not return immediately, OR // if in attention case, loop while no more pending data & attention has not yet been // received. while ((stateObj._pendingData && (RunBehavior.ReturnImmediately != (RunBehavior.ReturnImmediately & runBehavior))) || (!stateObj._pendingData && stateObj._attentionSent && !stateObj._attentionReceived)); #if DEBUG if ((stateObj._pendingData) && (!dataReady)) { byte token; if (!stateObj.TryPeekByte(out token)) { return false; } Debug.Assert(IsValidTdsToken(token), string.Format("DataReady is false, but next token is not valid: {0,-2:X2}", token)); } #endif if (!stateObj._pendingData) { if (null != CurrentTransaction) { CurrentTransaction.Activate(); } } // if we recieved an attention (but this thread didn't send it) then // we throw an Operation Cancelled error if (stateObj._attentionReceived) { // Dev11 #344723: SqlClient stress hang System_Data!Tcp::ReadSync via a call to SqlDataReader::Close // Spin until SendAttention has cleared _attentionSending, this prevents a race condition between receiving the attention ACK and setting _attentionSent SpinWait.SpinUntil(() => !stateObj._attentionSending); Debug.Assert(stateObj._attentionSent, "Attention ACK has been received without attention sent"); if (stateObj._attentionSent) { // Reset attention state. stateObj._attentionSent = false; stateObj._attentionReceived = false; if (RunBehavior.Clean != (RunBehavior.Clean & runBehavior) && !stateObj._internalTimeout) { // Add attention error to collection - if not RunBehavior.Clean! stateObj.AddError(new SqlError(0, 0, TdsEnums.MIN_ERROR_CLASS, _server, SQLMessage.OperationCancelled(), "", 0)); } } } if (stateObj.HasErrorOrWarning) { ThrowExceptionAndWarning(stateObj); } return true; }