mcs/tools/csharp/repl.cs

   1 //
   2 // repl.cs: Support for using the compiler in interactive mode (read-eval-print loop)
   3 //
   4 // Authors:
   5 //   Miguel de Icaza (miguel@gnome.org)
   6 //
   7 // Dual licensed under the terms of the MIT X11 or GNU GPL
   8 //
   9 // Copyright 2001, 2002, 2003 Ximian, Inc (http://www.ximian.com)
  10 // Copyright 2004, 2005, 2006, 2007, 2008 Novell, Inc
  11 // Copyright 2011-2013 Xamarin Inc
  12 //
  13 //
  14 // TODO:
  15 //   Do not print results in Evaluate, do that elsewhere in preparation for Eval refactoring.
  16 //   Driver.PartialReset should not reset the coretypes, nor the optional types, to avoid
  17 //      computing that on every call.
  18 //
  19 using System;
  20 using System.IO;
  21 using System.Text;
  22 using System.Globalization;
  23 using System.Collections;
  24 using System.Reflection;
  25 using System.Reflection.Emit;
  26 using System.Threading;
  27 using System.Net;
  28 using System.Net.Sockets;
  29 using System.Collections.Generic;
  30
  31 using Mono.CSharp;
  32
  33 namespace Mono {
  34
  35         public class Driver {
  36                 public static string StartupEvalExpression;
  37                 static int? attach;
  38                 static string target_host;
  39                 static int target_port;
  40                 static string agent;
  41
  42                 static int Main (string [] args)
  43                 {
  44                         var cmd = new CommandLineParser (Console.Out);
  45                         cmd.UnknownOptionHandler += HandleExtraArguments;
  46
  47                         // Enable unsafe code by default
  48                         var settings = new CompilerSettings () {
  49                                 Unsafe = true
  50                         };
  51
  52                         if (!cmd.ParseArguments (settings, args))
  53                                 return 1;
  54
  55                         var startup_files = new string [settings.SourceFiles.Count];
  56                         int i = 0;
  57                         foreach (var source in settings.SourceFiles)
  58                                 startup_files [i++] = source.FullPathName;
  59                         settings.SourceFiles.Clear ();
  60
  61                         TextWriter agent_stderr = null;
  62                         ReportPrinter printer;
  63                         if (agent != null) {
  64                                 agent_stderr = new StringWriter ();
  65                                 printer = new StreamReportPrinter (agent_stderr);
  66                         } else {
  67                                 printer = new ConsoleReportPrinter ();
  68                         }
  69
  70                         var eval = new Evaluator (new CompilerContext (settings, printer));
  71
  72                         eval.InteractiveBaseClass = typeof (InteractiveBaseShell);
  73                         eval.DescribeTypeExpressions = true;
  74                         eval.WaitOnTask = true;
  75
  76                         CSharpShell shell;
  77 #if !ON_DOTNET
  78                         if (attach.HasValue) {
  79                                 shell = new ClientCSharpShell_v1 (eval, attach.Value);
  80                         } else if (agent != null) {
  81                                 new CSharpAgent (eval, agent, agent_stderr).Run (startup_files);
  82                                 return 0;
  83                         } else
  84 #endif
  85                         if (target_host != null)
  86                                 shell = new ClientCSharpShell  (eval, target_host, target_port);
  87                         else
  88                                 shell = new CSharpShell (eval);
  89
  90                         return shell.Run (startup_files);
  91                 }
  92
  93                 static int HandleExtraArguments (string [] args, int pos)
  94                 {
  95                         switch (args [pos]) {
  96                         case "-e":
  97                                 if (pos + 1 < args.Length) {
  98                                         StartupEvalExpression = args[pos + 1];
  99                                         return pos + 1;
 100                                 }
 101                                 break;
 102                         case "--attach":
 103                                 if (pos + 1 < args.Length) {
 104                                         attach = Int32.Parse (args[1]);
 105                                         return pos + 1;
 106                                 }
 107                                 break;
 108                         default:
 109                                 if (args [pos].StartsWith ("--server=")){
 110                                         var hostport = args [pos].Substring (9);
 111                                         int p = hostport.IndexOf (':');
 112                                         if (p == -1){
 113                                                 target_host = hostport;
 114                                                 target_port = 10000;
 115                                         } else {
 116                                                 target_host = hostport.Substring (0,p);
 117                                                 if (!int.TryParse (hostport.Substring (p), out target_port)){
 118                                                         Console.Error.WriteLine ("Usage is: --server[=host[:port]");
 119                                                         Environment.Exit (1);
 120                                                 }
 121                                         }
 122                                         return pos + 1;
 123                                 }
 124                                 if (args [pos].StartsWith ("--client")){
 125                                         target_host = "localhost";
 126                                         target_port = 10000;
 127                                         return pos + 1;
 128                                 }
 129                                 if (args [pos].StartsWith ("--agent:")) {
 130                                         agent = args[pos];
 131                                         return pos + 1;
 132                                 } else {
 133                                         return -1;
 134                                 }
 135                         }
 136                         return -1;
 137                 }
 138
 139         }
 140
 141         public class InteractiveBaseShell : InteractiveBase {
 142                 static bool tab_at_start_completes;
 143
 144                 static InteractiveBaseShell ()
 145                 {
 146                         tab_at_start_completes = false;
 147                 }
 148
 149                 internal static Mono.Terminal.LineEditor Editor;
 150
 151                 public static bool TabAtStartCompletes {
 152                         get {
 153                                 return tab_at_start_completes;
 154                         }
 155
 156                         set {
 157                                 tab_at_start_completes = value;
 158                                 if (Editor != null)
 159                                         Editor.TabAtStartCompletes = value;
 160                         }
 161                 }
 162
 163                 public static new string help {
 164                         get {
 165                                 return InteractiveBase.help +
 166                                         "  TabAtStartCompletes      - Whether tab will complete even on empty lines\n";
 167                         }
 168                 }
 169         }
 170
 171         public class CSharpShell {
 172                 static bool isatty = true, is_unix = false;
 173                 protected string [] startup_files;
 174
 175                 Mono.Terminal.LineEditor editor;
 176                 bool dumb;
 177                 readonly Evaluator evaluator;
 178
 179                 public CSharpShell (Evaluator evaluator)
 180                 {
 181                         this.evaluator = evaluator;
 182                 }
 183
 184                 protected virtual void ConsoleInterrupt (object sender, ConsoleCancelEventArgs a)
 185                 {
 186                         // Do not about our program
 187                         a.Cancel = true;
 188
 189                         evaluator.Interrupt ();
 190                 }
 191
 192                 void SetupConsole ()
 193                 {
 194                         if (is_unix){
 195                                 string term = Environment.GetEnvironmentVariable ("TERM");
 196                                 dumb = term == "dumb" || term == null || isatty == false;
 197                         } else
 198                                 dumb = false;
 199
 200                         editor = new Mono.Terminal.LineEditor ("csharp", 300);
 201                         InteractiveBaseShell.Editor = editor;
 202
 203                         editor.AutoCompleteEvent += delegate (string s, int pos){
 204                                 string prefix = null;
 205
 206                                 string complete = s.Substring (0, pos);
 207
 208                                 string [] completions = evaluator.GetCompletions (complete, out prefix);
 209
 210                                 return new Mono.Terminal.LineEditor.Completion (prefix, completions);
 211                         };
 212
 213 #if false
 214                         //
 215                         // This is a sample of how completions sould be implemented.
 216                         //
 217                         editor.AutoCompleteEvent += delegate (string s, int pos){
 218
 219                                 // Single match: "Substring": Sub-string
 220                                 if (s.EndsWith ("Sub")){
 221                                         return new string [] { "string" };
 222                                 }
 223
 224                                 // Multiple matches: "ToString" and "ToLower"
 225                                 if (s.EndsWith ("T")){
 226                                         return new string [] { "ToString", "ToLower" };
 227                                 }
 228                                 return null;
 229                         };
 230 #endif
 231
 232                         Console.CancelKeyPress += ConsoleInterrupt;
 233                 }
 234
 235                 string GetLine (bool primary)
 236                 {
 237                         string prompt = primary ? InteractiveBase.Prompt : InteractiveBase.ContinuationPrompt;
 238
 239                         if (dumb){
 240                                 if (isatty)
 241                                         Console.Write (prompt);
 242
 243                                 return Console.ReadLine ();
 244                         } else {
 245                                 return editor.Edit (prompt, "");
 246                         }
 247                 }
 248
 249                 delegate string ReadLiner (bool primary);
 250
 251                 void InitializeUsing ()
 252                 {
 253                         Evaluate ("using System; using System.Linq; using System.Collections.Generic; using System.Collections;");
 254                 }
 255
 256                 void InitTerminal (bool show_banner)
 257                 {
 258                         int p = (int) Environment.OSVersion.Platform;
 259                         is_unix = (p == 4) || (p == 128);
 260
 261                         isatty = !Console.IsInputRedirected && !Console.IsOutputRedirected;
 262
 263                         // Work around, since Console is not accounting for
 264                         // cursor position when writing to Stderr.  It also
 265                         // has the undesirable side effect of making
 266                         // errors plain, with no coloring.
 267 //                      Report.Stderr = Console.Out;
 268                         SetupConsole ();
 269
 270                         if (isatty && show_banner)
 271                                 Console.WriteLine ("Mono C# Shell, type \"help;\" for help\n\nEnter statements below.");
 272
 273                 }
 274
 275                 void ExecuteSources (IEnumerable<string> sources, bool ignore_errors)
 276                 {
 277                         foreach (string file in sources){
 278                                 try {
 279                                         try {
 280                                                 bool first = true;
 281
 282                                                 using (System.IO.StreamReader r = System.IO.File.OpenText (file)){
 283                                                         ReadEvalPrintLoopWith (p => {
 284                                                                 var line = r.ReadLine ();
 285                                                                 if (first){
 286                                                                         if (line.StartsWith ("#!"))
 287                                                                                 line = r.ReadLine ();
 288                                                                         first = false;
 289                                                                 }
 290                                                                 return line;
 291                                                         });
 292                                                 }
 293                                         } catch (FileNotFoundException){
 294                                                 Console.Error.WriteLine ("cs2001: Source file `{0}' not found", file);
 295                                                 return;
 296                                         }
 297                                 } catch {
 298                                         if (!ignore_errors)
 299                                                 throw;
 300                                 }
 301                         }
 302                 }
 303
 304                 protected virtual void LoadStartupFiles ()
 305                 {
 306                         string dir = Path.Combine (
 307                                 Environment.GetFolderPath (Environment.SpecialFolder.ApplicationData),
 308                                 "csharp");
 309                         if (!Directory.Exists (dir))
 310                                 return;
 311
 312                         List<string> sources = new List<string> ();
 313                         List<string> libraries = new List<string> ();
 314
 315                         foreach (string file in System.IO.Directory.GetFiles (dir)){
 316                                 string l = file.ToLower ();
 317
 318                                 if (l.EndsWith (".cs"))
 319                                         sources.Add (file);
 320                                 else if (l.EndsWith (".dll"))
 321                                         libraries.Add (file);
 322                         }
 323
 324                         foreach (string file in libraries)
 325                                 evaluator.LoadAssembly (file);
 326
 327                         ExecuteSources (sources, true);
 328                 }
 329
 330                 void ReadEvalPrintLoopWith (ReadLiner readline)
 331                 {
 332                         string expr = null;
 333                         while (!InteractiveBase.QuitRequested){
 334                                 string input = readline (expr == null);
 335                                 if (input == null)
 336                                         return;
 337
 338                                 if (input == "")
 339                                         continue;
 340
 341                                 expr = expr == null ? input : expr + "\n" + input;
 342
 343                                 expr = Evaluate (expr);
 344                         }
 345                 }
 346
 347                 public int ReadEvalPrintLoop ()
 348                 {
 349                         if (startup_files != null && startup_files.Length == 0)
 350                                 InitTerminal (startup_files.Length == 0 && Driver.StartupEvalExpression == null);
 351
 352                         InitializeUsing ();
 353
 354                         LoadStartupFiles ();
 355
 356                         if (startup_files != null && startup_files.Length != 0) {
 357                                 ExecuteSources (startup_files, false);
 358                         } else {
 359                                 if (Driver.StartupEvalExpression != null){
 360                                         ReadEvalPrintLoopWith (p => {
 361                                                 var ret = Driver.StartupEvalExpression;
 362                                                 Driver.StartupEvalExpression = null;
 363                                                 return ret;
 364                                                 });
 365                                 } else {
 366                                         ReadEvalPrintLoopWith (GetLine);
 367                                 }
 368
 369                                 editor.SaveHistory ();
 370                         }
 371
 372                         Console.CancelKeyPress -= ConsoleInterrupt;
 373
 374                         return 0;
 375                 }
 376
 377                 protected virtual string Evaluate (string input)
 378                 {
 379                         bool result_set;
 380                         object result;
 381
 382                         try {
 383                                 input = evaluator.Evaluate (input, out result, out result_set);
 384
 385                                 if (result_set){
 386                                         PrettyPrint (Console.Out, result);
 387                                         Console.WriteLine ();
 388                                 }
 389                         } catch (Exception e){
 390                                 Console.WriteLine (e);
 391                                 return null;
 392                         }
 393
 394                         return input;
 395                 }
 396
 397                 static void p (TextWriter output, string s)
 398                 {
 399                         output.Write (s);
 400                 }
 401
 402                 static string EscapeString (string s)
 403                 {
 404                         return s.Replace ("\"", "\\\"");
 405                 }
 406
 407                 static void EscapeChar (TextWriter output, char c)
 408                 {
 409                         if (c == '\''){
 410                                 output.Write ("'\\''");
 411                                 return;
 412                         }
 413                         if (c > 32){
 414                                 output.Write ("'{0}'", c);
 415                                 return;
 416                         }
 417                         switch (c){
 418                         case '\a':
 419                                 output.Write ("'\\a'");
 420                                 break;
 421
 422                         case '\b':
 423                                 output.Write ("'\\b'");
 424                                 break;
 425
 426                         case '\n':
 427                                 output.Write ("'\\n'");
 428                                 break;
 429
 430                         case '\v':
 431                                 output.Write ("'\\v'");
 432                                 break;
 433
 434                         case '\r':
 435                                 output.Write ("'\\r'");
 436                                 break;
 437
 438                         case '\f':
 439                                 output.Write ("'\\f'");
 440                                 break;
 441
 442                         case '\t':
 443                                 output.Write ("'\\t");
 444                                 break;
 445
 446                         default:
 447                                 output.Write ("'\\x{0:x}", (int) c);
 448                                 break;
 449                         }
 450                 }
 451
 452                 // Some types (System.Json.JsonPrimitive) implement
 453                 // IEnumerator and yet, throw an exception when we
 454                 // try to use them, helper function to check for that
 455                 // condition
 456                 static internal bool WorksAsEnumerable (object obj)
 457                 {
 458                         IEnumerable enumerable = obj as IEnumerable;
 459                         if (enumerable != null){
 460                                 try {
 461                                         enumerable.GetEnumerator ();
 462                                         return true;
 463                                 } catch {
 464                                         // nothing, we return false below
 465                                 }
 466                         }
 467                         return false;
 468                 }
 469
 470                 internal static void PrettyPrint (TextWriter output, object result)
 471                 {
 472                         if (result == null){
 473                                 p (output, "null");
 474                                 return;
 475                         }
 476
 477                         if (result is Array){
 478                                 Array a = (Array) result;
 479
 480                                 p (output, "{ ");
 481                                 int top = a.GetUpperBound (0);
 482                                 for (int i = a.GetLowerBound (0); i <= top; i++){
 483                                         PrettyPrint (output, a.GetValue (i));
 484                                         if (i != top)
 485                                                 p (output, ", ");
 486                                 }
 487                                 p (output, " }");
 488                         } else if (result is bool){
 489                                 if ((bool) result)
 490                                         p (output, "true");
 491                                 else
 492                                         p (output, "false");
 493                         } else if (result is string){
 494                                 p (output, String.Format ("\"{0}\"", EscapeString ((string)result)));
 495                         } else if (result is IDictionary){
 496                                 IDictionary dict = (IDictionary) result;
 497                                 int top = dict.Count, count = 0;
 498
 499                                 p (output, "{");
 500                                 foreach (DictionaryEntry entry in dict){
 501                                         count++;
 502                                         p (output, "{ ");
 503                                         PrettyPrint (output, entry.Key);
 504                                         p (output, ", ");
 505                                         PrettyPrint (output, entry.Value);
 506                                         if (count != top)
 507                                                 p (output, " }, ");
 508                                         else
 509                                                 p (output, " }");
 510                                 }
 511                                 p (output, "}");
 512                         } else if (WorksAsEnumerable (result)) {
 513                                 int i = 0;
 514                                 p (output, "{ ");
 515                                 foreach (object item in (IEnumerable) result) {
 516                                         if (i++ != 0)
 517                                                 p (output, ", ");
 518
 519                                         PrettyPrint (output, item);
 520                                 }
 521                                 p (output, " }");
 522                         } else if (result is char) {
 523                                 EscapeChar (output, (char) result);
 524                         } else {
 525                                 p (output, result.ToString ());
 526                         }
 527                 }
 528
 529                 public virtual int Run (string [] startup_files)
 530                 {
 531                         this.startup_files = startup_files;
 532                         return ReadEvalPrintLoop ();
 533                 }
 534
 535         }
 536
 537         //
 538         // Stream helper extension methods
 539         //
 540         public static class StreamHelper {
 541                 static DataConverter converter = DataConverter.LittleEndian;
 542
 543                 static void GetBuffer (this Stream stream, byte [] b)
 544                 {
 545                         int n, offset = 0;
 546                         int len = b.Length;
 547
 548                         do {
 549                                 n = stream.Read (b, offset, len);
 550                                 if (n == 0)
 551                                         throw new IOException ("End reached");
 552
 553                                 offset += n;
 554                                 len -= n;
 555                         } while (len > 0);
 556                 }
 557
 558                 public static int GetInt (this Stream stream)
 559                 {
 560                         byte [] b = new byte [4];
 561                         stream.GetBuffer (b);
 562                         return converter.GetInt32 (b, 0);
 563                 }
 564
 565                 public static string GetString (this Stream stream)
 566                 {
 567                         int len = stream.GetInt ();
 568                         if (len == 0)
 569                                 return "";
 570
 571                         byte [] b = new byte [len];
 572                         stream.GetBuffer (b);
 573
 574                         return Encoding.UTF8.GetString (b);
 575                 }
 576
 577                 public static void WriteInt (this Stream stream, int n)
 578                 {
 579                         byte [] bytes = converter.GetBytes (n);
 580                         stream.Write (bytes, 0, bytes.Length);
 581                 }
 582
 583                 public static void WriteString (this Stream stream, string s)
 584                 {
 585                         stream.WriteInt (s.Length);
 586                         byte [] bytes = Encoding.UTF8.GetBytes (s);
 587                         stream.Write (bytes, 0, bytes.Length);
 588                 }
 589         }
 590
 591         public enum AgentStatus : byte {
 592                 // Received partial input, complete
 593                 PARTIAL_INPUT  = 1,
 594
 595                 // The result was set, expect the string with the result
 596                 RESULT_SET     = 2,
 597
 598                 // No result was set, complete
 599                 RESULT_NOT_SET = 3,
 600
 601                 // Errors and warnings string follows
 602                 ERROR          = 4,
 603
 604                 // Stdout
 605                 STDOUT         = 5,
 606         }
 607
 608         class ClientCSharpShell : CSharpShell {
 609                 string target_host;
 610                 int target_port;
 611
 612                 public ClientCSharpShell (Evaluator evaluator, string target_host, int target_port) : base (evaluator)
 613                 {
 614                         this.target_port = target_port;
 615                         this.target_host = target_host;
 616                 }
 617
 618                 T ConnectServer<T> (Func<NetworkStream,T> callback, Action<Exception> error)
 619                 {
 620                         try {
 621                                 var client = new TcpClient (target_host, target_port);
 622                                 var ns = client.GetStream ();
 623                                 T ret = callback (ns);
 624                                 ns.Flush ();
 625                                 ns.Close ();
 626                                 client.Close ();
 627                                 return ret;
 628                         } catch (Exception e){
 629                                 error (e);
 630                                 return default(T);
 631                         }
 632                 }
 633
 634                 protected override string Evaluate (string input)
 635                 {
 636                         return ConnectServer<string> ((ns)=> {
 637                                 try {
 638                                         ns.WriteString ("EVALTXT");
 639                                         ns.WriteString (input);
 640
 641                                         while (true) {
 642                                                 AgentStatus s = (AgentStatus) ns.ReadByte ();
 643
 644                                                 switch (s){
 645                                                 case AgentStatus.PARTIAL_INPUT:
 646                                                         return input;
 647
 648                                                 case AgentStatus.ERROR:
 649                                                         string err = ns.GetString ();
 650                                                         Console.Error.WriteLine (err);
 651                                                         break;
 652
 653                                                 case AgentStatus.STDOUT:
 654                                                         string stdout = ns.GetString ();
 655                                                         Console.WriteLine (stdout);
 656                                                         break;
 657
 658                                                 case AgentStatus.RESULT_NOT_SET:
 659                                                         return null;
 660
 661                                                 case AgentStatus.RESULT_SET:
 662                                                         string res = ns.GetString ();
 663                                                         Console.WriteLine (res);
 664                                                         return null;
 665                                                 }
 666                                         }
 667                                 } catch (Exception e){
 668                                         Console.Error.WriteLine ("Error evaluating expression, exception: {0}", e);
 669                                 }
 670                                 return null;
 671                         }, (e) => {
 672                                 Console.Error.WriteLine ("Error communicating with server {0}", e);
 673                         });
 674                 }
 675
 676                 public override int Run (string [] startup_files)
 677                 {
 678                         // The difference is that we do not call Evaluator.Init, that is done on the target
 679                         this.startup_files = startup_files;
 680                         return ReadEvalPrintLoop ();
 681                 }
 682
 683                 protected override void ConsoleInterrupt (object sender, ConsoleCancelEventArgs a)
 684                 {
 685                         ConnectServer<int> ((ns)=> {
 686                                 ns.WriteString ("INTERRUPT");
 687                                 return 0;
 688                         }, (e) => { });
 689                 }
 690
 691         }
 692
 693 #if !ON_DOTNET
 694         //
 695         // A shell connected to a CSharpAgent running in a remote process.
 696         //  - maybe add 'class_name' and 'method_name' arguments to LoadAgent.
 697         //  - Support Gtk and Winforms main loops if detected, this should
 698         //    probably be done as a separate agent in a separate place.
 699         //
 700         class ClientCSharpShell_v1 : CSharpShell {
 701                 NetworkStream ns, interrupt_stream;
 702
 703                 public ClientCSharpShell_v1 (Evaluator evaluator, int pid)
 704                         : base (evaluator)
 705                 {
 706                         // Create a server socket we listen on whose address is passed to the agent
 707                         TcpListener listener = new TcpListener (new IPEndPoint (IPAddress.Loopback, 0));
 708                         listener.Start ();
 709                         TcpListener interrupt_listener = new TcpListener (new IPEndPoint (IPAddress.Loopback, 0));
 710                         interrupt_listener.Start ();
 711
 712                         string agent_assembly = typeof (ClientCSharpShell).Assembly.Location;
 713                         string agent_arg = String.Format ("--agent:{0}:{1}" ,
 714                                                           ((IPEndPoint)listener.Server.LocalEndPoint).Port,
 715                                                           ((IPEndPoint)interrupt_listener.Server.LocalEndPoint).Port);
 716
 717                         var vm = new Attach.VirtualMachine (pid);
 718                         vm.Attach (agent_assembly, agent_arg);
 719
 720                         /* Wait for the client to connect */
 721                         TcpClient client = listener.AcceptTcpClient ();
 722                         ns = client.GetStream ();
 723                         TcpClient interrupt_client = interrupt_listener.AcceptTcpClient ();
 724                         interrupt_stream = interrupt_client.GetStream ();
 725
 726                         Console.WriteLine ("Connected.");
 727                 }
 728
 729                 //
 730                 // A remote version of Evaluate
 731                 //
 732                 protected override string Evaluate (string input)
 733                 {
 734                         ns.WriteString (input);
 735                         while (true) {
 736                                 AgentStatus s = (AgentStatus) ns.ReadByte ();
 737
 738                                 switch (s){
 739                                 case AgentStatus.PARTIAL_INPUT:
 740                                         return input;
 741
 742                                 case AgentStatus.ERROR:
 743                                         string err = ns.GetString ();
 744                                         Console.Error.WriteLine (err);
 745                                         break;
 746
 747                                 case AgentStatus.RESULT_NOT_SET:
 748                                         return null;
 749
 750                                 case AgentStatus.RESULT_SET:
 751                                         string res = ns.GetString ();
 752                                         Console.WriteLine (res);
 753                                         return null;
 754                                 }
 755                         }
 756                 }
 757
 758                 public override int Run (string [] startup_files)
 759                 {
 760                         // The difference is that we do not call Evaluator.Init, that is done on the target
 761                         this.startup_files = startup_files;
 762                         return ReadEvalPrintLoop ();
 763                 }
 764
 765                 protected override void ConsoleInterrupt (object sender, ConsoleCancelEventArgs a)
 766                 {
 767                         // Do not about our program
 768                         a.Cancel = true;
 769
 770                         interrupt_stream.WriteByte (0);
 771                         int c = interrupt_stream.ReadByte ();
 772                         if (c != -1)
 773                                 Console.WriteLine ("Execution interrupted");
 774                 }
 775
 776         }
 777
 778         //
 779         // This is the agent loaded into the target process when using --attach.
 780         //
 781         class CSharpAgent
 782         {
 783                 NetworkStream interrupt_stream;
 784                 readonly Evaluator evaluator;
 785                 TextWriter stderr;
 786
 787                 public CSharpAgent (Evaluator evaluator, String arg, TextWriter stderr)
 788                 {
 789                         this.evaluator = evaluator;
 790                         this.stderr = stderr;
 791                         new Thread (new ParameterizedThreadStart (Run)).Start (arg);
 792                 }
 793
 794                 public void InterruptListener ()
 795                 {
 796                         while (true){
 797                                 int b = interrupt_stream.ReadByte();
 798                                 if (b == -1)
 799                                         return;
 800                                 evaluator.Interrupt ();
 801                                 interrupt_stream.WriteByte (0);
 802                         }
 803                 }
 804
 805                 public void Run (object o)
 806                 {
 807                         string arg = (string)o;
 808                         string ports = arg.Substring (8);
 809                         int sp = ports.IndexOf (':');
 810                         int port = Int32.Parse (ports.Substring (0, sp));
 811                         int interrupt_port = Int32.Parse (ports.Substring (sp+1));
 812
 813                         Console.WriteLine ("csharp-agent: started, connecting to localhost:" + port);
 814
 815                         TcpClient client = new TcpClient ("127.0.0.1", port);
 816                         TcpClient interrupt_client = new TcpClient ("127.0.0.1", interrupt_port);
 817                         Console.WriteLine ("csharp-agent: connected.");
 818
 819                         NetworkStream s = client.GetStream ();
 820                         interrupt_stream = interrupt_client.GetStream ();
 821                         new Thread (InterruptListener).Start ();
 822
 823                         try {
 824                                 // Add all assemblies loaded later
 825                                 AppDomain.CurrentDomain.AssemblyLoad += AssemblyLoaded;
 826
 827                                 // Add all currently loaded assemblies
 828                                 foreach (Assembly a in AppDomain.CurrentDomain.GetAssemblies ()) {
 829                                         // Some assemblies seem to be already loaded, and loading them again causes 'defined multiple times' errors
 830                                         if (a.GetName ().Name != "mscorlib" && a.GetName ().Name != "System.Core" && a.GetName ().Name != "System")
 831                                                 evaluator.ReferenceAssembly (a);
 832                                 }
 833
 834                                 RunRepl (s);
 835                         } finally {
 836                                 AppDomain.CurrentDomain.AssemblyLoad -= AssemblyLoaded;
 837                                 client.Close ();
 838                                 interrupt_client.Close ();
 839                                 Console.WriteLine ("csharp-agent: disconnected.");
 840                         }
 841                 }
 842
 843                 void AssemblyLoaded (object sender, AssemblyLoadEventArgs e)
 844                 {
 845                         evaluator.ReferenceAssembly (e.LoadedAssembly);
 846                 }
 847
 848                 public void RunRepl (NetworkStream s)
 849                 {
 850                         string input = null;
 851
 852                         while (!InteractiveBase.QuitRequested) {
 853                                 try {
 854                                         string error_string;
 855                                         StringWriter error_output = (StringWriter)stderr;
 856
 857                                         string line = s.GetString ();
 858
 859                                         bool result_set;
 860                                         object result;
 861
 862                                         if (input == null)
 863                                                 input = line;
 864                                         else
 865                                                 input = input + "\n" + line;
 866
 867                                         try {
 868                                                 input = evaluator.Evaluate (input, out result, out result_set);
 869                                         } catch (Exception e) {
 870                                                 s.WriteByte ((byte) AgentStatus.ERROR);
 871                                                 s.WriteString (e.ToString ());
 872                                                 s.WriteByte ((byte) AgentStatus.RESULT_NOT_SET);
 873                                                 continue;
 874                                         }
 875
 876                                         if (input != null){
 877                                                 s.WriteByte ((byte) AgentStatus.PARTIAL_INPUT);
 878                                                 continue;
 879                                         }
 880
 881                                         // Send warnings and errors back
 882                                         error_string = error_output.ToString ();
 883                                         if (error_string.Length != 0){
 884                                                 s.WriteByte ((byte) AgentStatus.ERROR);
 885                                                 s.WriteString (error_output.ToString ());
 886                                                 error_output.GetStringBuilder ().Clear ();
 887                                         }
 888
 889                                         if (result_set){
 890                                                 s.WriteByte ((byte) AgentStatus.RESULT_SET);
 891                                                 StringWriter sr = new StringWriter ();
 892                                                 CSharpShell.PrettyPrint (sr, result);
 893                                                 s.WriteString (sr.ToString ());
 894                                         } else {
 895                                                 s.WriteByte ((byte) AgentStatus.RESULT_NOT_SET);
 896                                         }
 897                                 } catch (IOException) {
 898                                         break;
 899                                 } catch (Exception e){
 900                                         Console.WriteLine (e);
 901                                 }
 902                         }
 903                 }
 904         }
 905
 906         public class UnixUtils {
 907                 [System.Runtime.InteropServices.DllImport ("libc", EntryPoint="isatty")]
 908                 extern static int _isatty (int fd);
 909
 910                 public static bool isatty (int fd)
 911                 {
 912                         try {
 913                                 return _isatty (fd) == 1;
 914                         } catch {
 915                                 return false;
 916                         }
 917                 }
 918         }
 919 #endif
 920 }
 921
 922 namespace Mono.Management
 923 {
 924         interface IVirtualMachine {
 925                 void LoadAgent (string filename, string args);
 926         }
 927 }
 928