Parallel workers support for "gfix". (#1065)

Author: cincuranet

src/FirebirdSql.Data.FirebirdClient/Common/IscCodes.cs

@@ -606,6 +606,7 @@ internal static class IscCodes
 	public const int isc_spb_rpr_commit_trans_64 = 49;
 	public const int isc_spb_rpr_rollback_trans_64 = 50;
 	public const int isc_spb_rpr_recover_two_phase_64 = 51;
+	public const int isc_spb_rpr_par_workers = 52;
 
 	public const int isc_spb_rpr_validate_db = 0x01;
 	public const int isc_spb_rpr_sweep_db = 0x02;

src/FirebirdSql.Data.FirebirdClient/Services/FbValidation.cs

@@ -44,6 +44,8 @@ public void Execute()
 				startSpb.Append(IscCodes.isc_action_svc_repair);
 				startSpb.Append2(IscCodes.isc_spb_dbname, Database);
 				startSpb.Append(IscCodes.isc_spb_options, (int)Options);
+				if (ConnectionStringOptions.ParallelWorkers > 0)
+					startSpb.Append(IscCodes.isc_spb_rpr_par_workers, ConnectionStringOptions.ParallelWorkers);
 				StartTask(startSpb);
 				ProcessServiceOutput(new ServiceParameterBuffer2(Service.ParameterBufferEncoding));
 			}
@@ -70,6 +72,8 @@ public async Task ExecuteAsync(CancellationToken cancellationToken = default)
 				startSpb.Append(IscCodes.isc_action_svc_repair);
 				startSpb.Append2(IscCodes.isc_spb_dbname, Database);
 				startSpb.Append(IscCodes.isc_spb_options, (int)Options);
+				if (ConnectionStringOptions.ParallelWorkers > 0)
+					startSpb.Append(IscCodes.isc_spb_rpr_par_workers, ConnectionStringOptions.ParallelWorkers);
 				await StartTaskAsync(startSpb, cancellationToken).ConfigureAwait(false);
 				await ProcessServiceOutputAsync(new ServiceParameterBuffer2(Service.ParameterBufferEncoding), cancellationToken).ConfigureAwait(false);
 			}