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 #if NET_4_5
 262                         isatty = !Console.IsInputRedirected && !Console.IsOutputRedirected;
 263 #else
 264                         isatty = true;
 265 #endif
 266
 267                         // Work around, since Console is not accounting for
 268                         // cursor position when writing to Stderr.  It also
 269                         // has the undesirable side effect of making
 270                         // errors plain, with no coloring.
 271 //                      Report.Stderr = Console.Out;
 272                         SetupConsole ();
 273
 274                         if (isatty && show_banner)
 275                                 Console.WriteLine ("Mono C# Shell, type \"help;\" for help\n\nEnter statements below.");
 276
 277                 }
 278
 279                 void ExecuteSources (IEnumerable<string> sources, bool ignore_errors)
 280                 {
 281                         foreach (string file in sources){
 282                                 try {
 283                                         try {
 284                                                 bool first = true;
 285
 286                                                 using (System.IO.StreamReader r = System.IO.File.OpenText (file)){
 287                                                         ReadEvalPrintLoopWith (p => {
 288                                                                 var line = r.ReadLine ();
 289                                                                 if (first){
 290                                                                         if (line.StartsWith ("#!"))
 291                                                                                 line = r.ReadLine ();
 292                                                                         first = false;
 293                                                                 }
 294                                                                 return line;
 295                                                         });
 296                                                 }
 297                                         } catch (FileNotFoundException){
 298                                                 Console.Error.WriteLine ("cs2001: Source file `{0}' not found", file);
 299                                                 return;
 300                                         }
 301                                 } catch {
 302                                         if (!ignore_errors)
 303                                                 throw;
 304                                 }
 305                         }
 306                 }
 307
 308                 protected virtual void LoadStartupFiles ()
 309                 {
 310                         string dir = Path.Combine (
 311                                 Environment.GetFolderPath (Environment.SpecialFolder.ApplicationData),
 312                                 "csharp");
 313                         if (!Directory.Exists (dir))
 314                                 return;
 315
 316                         List<string> sources = new List<string> ();
 317                         List<string> libraries = new List<string> ();
 318
 319                         foreach (string file in System.IO.Directory.GetFiles (dir)){
 320                                 string l = file.ToLower ();
 321
 322                                 if (l.EndsWith (".cs"))
 323                                         sources.Add (file);
 324                                 else if (l.EndsWith (".dll"))
 325                                         libraries.Add (file);
 326                         }
 327
 328                         foreach (string file in libraries)
 329                                 evaluator.LoadAssembly (file);
 330
 331                         ExecuteSources (sources, true);
 332                 }
 333
 334                 void ReadEvalPrintLoopWith (ReadLiner readline)
 335                 {
 336                         string expr = null;
 337                         while (!InteractiveBase.QuitRequested){
 338                                 string input = readline (expr == null);
 339                                 if (input == null)
 340                                         return;
 341
 342                                 if (input == "")
 343                                         continue;
 344
 345                                 expr = expr == null ? input : expr + "\n" + input;
 346
 347                                 expr = Evaluate (expr);
 348                         }
 349                 }
 350
 351                 public int ReadEvalPrintLoop ()
 352                 {
 353                         if (startup_files != null && startup_files.Length == 0)
 354                                 InitTerminal (startup_files.Length == 0 && Driver.StartupEvalExpression == null);
 355
 356                         InitializeUsing ();
 357
 358                         LoadStartupFiles ();
 359
 360                         if (startup_files != null && startup_files.Length != 0) {
 361                                 ExecuteSources (startup_files, false);
 362                         } else {
 363                                 if (Driver.StartupEvalExpression != null){
 364                                         ReadEvalPrintLoopWith (p => {
 365                                                 var ret = Driver.StartupEvalExpression;
 366                                                 Driver.StartupEvalExpression = null;
 367                                                 return ret;
 368                                                 });
 369                                 } else {
 370                                         ReadEvalPrintLoopWith (GetLine);
 371                                 }
 372
 373                                 editor.SaveHistory ();
 374                         }
 375
 376                         Console.CancelKeyPress -= ConsoleInterrupt;
 377
 378                         return 0;
 379                 }
 380
 381                 protected virtual string Evaluate (string input)
 382                 {
 383                         bool result_set;
 384                         object result;
 385
 386                         try {
 387                                 input = evaluator.Evaluate (input, out result, out result_set);
 388
 389                                 if (result_set){
 390                                         PrettyPrint (Console.Out, result);
 391                                         Console.WriteLine ();
 392                                 }
 393                         } catch (Exception e){
 394                                 Console.WriteLine (e);
 395                                 return null;
 396                         }
 397
 398                         return input;
 399                 }
 400
 401                 static void p (TextWriter output, string s)
 402                 {
 403                         output.Write (s);
 404                 }
 405
 406                 static string EscapeString (string s)
 407                 {
 408                         return s.Replace ("\"", "\\\"");
 409                 }
 410
 411                 static void EscapeChar (TextWriter output, char c)
 412                 {
 413                         if (c == '\''){
 414                                 output.Write ("'\\''");
 415                                 return;
 416                         }
 417                         if (c > 32){
 418                                 output.Write ("'{0}'", c);
 419                                 return;
 420                         }
 421                         switch (c){
 422                         case '\a':
 423                                 output.Write ("'\\a'");
 424                                 break;
 425
 426                         case '\b':
 427                                 output.Write ("'\\b'");
 428                                 break;
 429
 430                         case '\n':
 431                                 output.Write ("'\\n'");
 432                                 break;
 433
 434                         case '\v':
 435                                 output.Write ("'\\v'");
 436                                 break;
 437
 438                         case '\r':
 439                                 output.Write ("'\\r'");
 440                                 break;
 441
 442                         case '\f':
 443                                 output.Write ("'\\f'");
 444                                 break;
 445
 446                         case '\t':
 447                                 output.Write ("'\\t");
 448                                 break;
 449
 450                         default:
 451                                 output.Write ("'\\x{0:x}", (int) c);
 452                                 break;
 453                         }
 454                 }
 455
 456                 // Some types (System.Json.JsonPrimitive) implement
 457                 // IEnumerator and yet, throw an exception when we
 458                 // try to use them, helper function to check for that
 459                 // condition
 460                 static internal bool WorksAsEnumerable (object obj)
 461                 {
 462                         IEnumerable enumerable = obj as IEnumerable;
 463                         if (enumerable != null){
 464                                 try {
 465                                         enumerable.GetEnumerator ();
 466                                         return true;
 467                                 } catch {
 468                                         // nothing, we return false below
 469                                 }
 470                         }
 471                         return false;
 472                 }
 473
 474                 internal static void PrettyPrint (TextWriter output, object result)
 475                 {
 476                         if (result == null){
 477                                 p (output, "null");
 478                                 return;
 479                         }
 480
 481                         if (result is Array){
 482                                 Array a = (Array) result;
 483
 484                                 p (output, "{ ");
 485                                 int top = a.GetUpperBound (0);
 486                                 for (int i = a.GetLowerBound (0); i <= top; i++){
 487                                         PrettyPrint (output, a.GetValue (i));
 488                                         if (i != top)
 489                                                 p (output, ", ");
 490                                 }
 491                                 p (output, " }");
 492                         } else if (result is bool){
 493                                 if ((bool) result)
 494                                         p (output, "true");
 495                                 else
 496                                         p (output, "false");
 497                         } else if (result is string){
 498                                 p (output, String.Format ("\"{0}\"", EscapeString ((string)result)));
 499                         } else if (result is IDictionary){
 500                                 IDictionary dict = (IDictionary) result;
 501                                 int top = dict.Count, count = 0;
 502
 503                                 p (output, "{");
 504                                 foreach (DictionaryEntry entry in dict){
 505                                         count++;
 506                                         p (output, "{ ");
 507                                         PrettyPrint (output, entry.Key);
 508                                         p (output, ", ");
 509                                         PrettyPrint (output, entry.Value);
 510                                         if (count != top)
 511                                                 p (output, " }, ");
 512                                         else
 513                                                 p (output, " }");
 514                                 }
 515                                 p (output, "}");
 516                         } else if (WorksAsEnumerable (result)) {
 517                                 int i = 0;
 518                                 p (output, "{ ");
 519                                 foreach (object item in (IEnumerable) result) {
 520                                         if (i++ != 0)
 521                                                 p (output, ", ");
 522
 523                                         PrettyPrint (output, item);
 524                                 }
 525                                 p (output, " }");
 526                         } else if (result is char) {
 527                                 EscapeChar (output, (char) result);
 528                         } else {
 529                                 p (output, result.ToString ());
 530                         }
 531                 }
 532
 533                 public virtual int Run (string [] startup_files)
 534                 {
 535                         this.startup_files = startup_files;
 536                         return ReadEvalPrintLoop ();
 537                 }
 538
 539         }
 540
 541         //
 542         // Stream helper extension methods
 543         //
 544         public static class StreamHelper {
 545                 static DataConverter converter = DataConverter.LittleEndian;
 546
 547                 static void GetBuffer (this Stream stream, byte [] b)
 548                 {
 549                         int n, offset = 0;
 550                         int len = b.Length;
 551
 552                         do {
 553                                 n = stream.Read (b, offset, len);
 554                                 if (n == 0)
 555                                         throw new IOException ("End reached");
 556
 557                                 offset += n;
 558                                 len -= n;
 559                         } while (len > 0);
 560                 }
 561
 562                 public static int GetInt (this Stream stream)
 563                 {
 564                         byte [] b = new byte [4];
 565                         stream.GetBuffer (b);
 566                         return converter.GetInt32 (b, 0);
 567                 }
 568
 569                 public static string GetString (this Stream stream)
 570                 {
 571                         int len = stream.GetInt ();
 572                         if (len == 0)
 573                                 return "";
 574
 575                         byte [] b = new byte [len];
 576                         stream.GetBuffer (b);
 577
 578                         return Encoding.UTF8.GetString (b);
 579                 }
 580
 581                 public static void WriteInt (this Stream stream, int n)
 582                 {
 583                         byte [] bytes = converter.GetBytes (n);
 584                         stream.Write (bytes, 0, bytes.Length);
 585                 }
 586
 587                 public static void WriteString (this Stream stream, string s)
 588                 {
 589                         stream.WriteInt (s.Length);
 590                         byte [] bytes = Encoding.UTF8.GetBytes (s);
 591                         stream.Write (bytes, 0, bytes.Length);
 592                 }
 593         }
 594
 595         public enum AgentStatus : byte {
 596                 // Received partial input, complete
 597                 PARTIAL_INPUT  = 1,
 598
 599                 // The result was set, expect the string with the result
 600                 RESULT_SET     = 2,
 601
 602                 // No result was set, complete
 603                 RESULT_NOT_SET = 3,
 604
 605                 // Errors and warnings string follows
 606                 ERROR          = 4,
 607         }
 608
 609         class ClientCSharpShell : CSharpShell {
 610                 string target_host;
 611                 int target_port;
 612
 613                 public ClientCSharpShell (Evaluator evaluator, string target_host, int target_port) : base (evaluator)
 614                 {
 615                         this.target_port = target_port;
 616                         this.target_host = target_host;
 617                 }
 618
 619                 T ConnectServer<T> (Func<NetworkStream,T> callback, Action<Exception> error)
 620                 {
 621                         try {
 622                                 var client = new TcpClient (target_host, target_port);
 623                                 var ns = client.GetStream ();
 624                                 T ret = callback (ns);
 625                                 ns.Flush ();
 626                                 ns.Close ();
 627                                 client.Close ();
 628                                 return ret;
 629                         } catch (Exception e){
 630                                 error (e);
 631                                 return default(T);
 632                         }
 633                 }
 634
 635                 protected override string Evaluate (string input)
 636                 {
 637                         return ConnectServer<string> ((ns)=> {
 638                                 try {
 639                                         ns.WriteString ("EVALTXT");
 640                                         ns.WriteString (input);
 641
 642                                         while (true) {
 643                                                 AgentStatus s = (AgentStatus) ns.ReadByte ();
 644
 645                                                 switch (s){
 646                                                 case AgentStatus.PARTIAL_INPUT:
 647                                                         return input;
 648
 649                                                 case AgentStatus.ERROR:
 650                                                         string err = ns.GetString ();
 651                                                         Console.Error.WriteLine (err);
 652                                                         break;
 653
 654                                                 case AgentStatus.RESULT_NOT_SET:
 655                                                         return null;
 656
 657                                                 case AgentStatus.RESULT_SET:
 658                                                         string res = ns.GetString ();
 659                                                         Console.WriteLine (res);
 660                                                         return null;
 661                                                 }
 662                                         }
 663                                 } catch (Exception e){
 664                                         Console.Error.WriteLine ("Error evaluating expression, exception: {0}", e);
 665                                 }
 666                                 return null;
 667                         }, (e) => {
 668                                 Console.Error.WriteLine ("Error communicating with server {0}", e);
 669                         });
 670                 }
 671
 672                 public override int Run (string [] startup_files)
 673                 {
 674                         // The difference is that we do not call Evaluator.Init, that is done on the target
 675                         this.startup_files = startup_files;
 676                         return ReadEvalPrintLoop ();
 677                 }
 678
 679                 protected override void ConsoleInterrupt (object sender, ConsoleCancelEventArgs a)
 680                 {
 681                         ConnectServer<int> ((ns)=> {
 682                                 ns.WriteString ("INTERRUPT");
 683                                 return 0;
 684                         }, (e) => { });
 685                 }
 686
 687         }
 688
 689 #if !ON_DOTNET
 690         //
 691         // A shell connected to a CSharpAgent running in a remote process.
 692         //  - maybe add 'class_name' and 'method_name' arguments to LoadAgent.
 693         //  - Support Gtk and Winforms main loops if detected, this should
 694         //    probably be done as a separate agent in a separate place.
 695         //
 696         class ClientCSharpShell_v1 : CSharpShell {
 697                 NetworkStream ns, interrupt_stream;
 698
 699                 public ClientCSharpShell_v1 (Evaluator evaluator, int pid)
 700                         : base (evaluator)
 701                 {
 702                         // Create a server socket we listen on whose address is passed to the agent
 703                         TcpListener listener = new TcpListener (new IPEndPoint (IPAddress.Loopback, 0));
 704                         listener.Start ();
 705                         TcpListener interrupt_listener = new TcpListener (new IPEndPoint (IPAddress.Loopback, 0));
 706                         interrupt_listener.Start ();
 707
 708                         string agent_assembly = typeof (ClientCSharpShell).Assembly.Location;
 709                         string agent_arg = String.Format ("--agent:{0}:{1}" ,
 710                                                           ((IPEndPoint)listener.Server.LocalEndPoint).Port,
 711                                                           ((IPEndPoint)interrupt_listener.Server.LocalEndPoint).Port);
 712
 713                         var vm = new Attach.VirtualMachine (pid);
 714                         vm.Attach (agent_assembly, agent_arg);
 715
 716                         /* Wait for the client to connect */
 717                         TcpClient client = listener.AcceptTcpClient ();
 718                         ns = client.GetStream ();
 719                         TcpClient interrupt_client = interrupt_listener.AcceptTcpClient ();
 720                         interrupt_stream = interrupt_client.GetStream ();
 721
 722                         Console.WriteLine ("Connected.");
 723                 }
 724
 725                 //
 726                 // A remote version of Evaluate
 727                 //
 728                 protected override string Evaluate (string input)
 729                 {
 730                         ns.WriteString (input);
 731                         while (true) {
 732                                 AgentStatus s = (AgentStatus) ns.ReadByte ();
 733
 734                                 switch (s){
 735                                 case AgentStatus.PARTIAL_INPUT:
 736                                         return input;
 737
 738                                 case AgentStatus.ERROR:
 739                                         string err = ns.GetString ();
 740                                         Console.Error.WriteLine (err);
 741                                         break;
 742
 743                                 case AgentStatus.RESULT_NOT_SET:
 744                                         return null;
 745
 746                                 case AgentStatus.RESULT_SET:
 747                                         string res = ns.GetString ();
 748                                         Console.WriteLine (res);
 749                                         return null;
 750                                 }
 751                         }
 752                 }
 753
 754                 public override int Run (string [] startup_files)
 755                 {
 756                         // The difference is that we do not call Evaluator.Init, that is done on the target
 757                         this.startup_files = startup_files;
 758                         return ReadEvalPrintLoop ();
 759                 }
 760
 761                 protected override void ConsoleInterrupt (object sender, ConsoleCancelEventArgs a)
 762                 {
 763                         // Do not about our program
 764                         a.Cancel = true;
 765
 766                         interrupt_stream.WriteByte (0);
 767                         int c = interrupt_stream.ReadByte ();
 768                         if (c != -1)
 769                                 Console.WriteLine ("Execution interrupted");
 770                 }
 771
 772         }
 773
 774         //
 775         // This is the agent loaded into the target process when using --attach.
 776         //
 777         class CSharpAgent
 778         {
 779                 NetworkStream interrupt_stream;
 780                 readonly Evaluator evaluator;
 781                 TextWriter stderr;
 782
 783                 public CSharpAgent (Evaluator evaluator, String arg, TextWriter stderr)
 784                 {
 785                         this.evaluator = evaluator;
 786                         this.stderr = stderr;
 787                         new Thread (new ParameterizedThreadStart (Run)).Start (arg);
 788                 }
 789
 790                 public void InterruptListener ()
 791                 {
 792                         while (true){
 793                                 int b = interrupt_stream.ReadByte();
 794                                 if (b == -1)
 795                                         return;
 796                                 evaluator.Interrupt ();
 797                                 interrupt_stream.WriteByte (0);
 798                         }
 799                 }
 800
 801                 public void Run (object o)
 802                 {
 803                         string arg = (string)o;
 804                         string ports = arg.Substring (8);
 805                         int sp = ports.IndexOf (':');
 806                         int port = Int32.Parse (ports.Substring (0, sp));
 807                         int interrupt_port = Int32.Parse (ports.Substring (sp+1));
 808
 809                         Console.WriteLine ("csharp-agent: started, connecting to localhost:" + port);
 810
 811                         TcpClient client = new TcpClient ("127.0.0.1", port);
 812                         TcpClient interrupt_client = new TcpClient ("127.0.0.1", interrupt_port);
 813                         Console.WriteLine ("csharp-agent: connected.");
 814
 815                         NetworkStream s = client.GetStream ();
 816                         interrupt_stream = interrupt_client.GetStream ();
 817                         new Thread (InterruptListener).Start ();
 818
 819                         try {
 820                                 // Add all assemblies loaded later
 821                                 AppDomain.CurrentDomain.AssemblyLoad += AssemblyLoaded;
 822
 823                                 // Add all currently loaded assemblies
 824                                 foreach (Assembly a in AppDomain.CurrentDomain.GetAssemblies ()) {
 825                                         // Some assemblies seem to be already loaded, and loading them again causes 'defined multiple times' errors
 826                                         if (a.GetName ().Name != "mscorlib" && a.GetName ().Name != "System.Core" && a.GetName ().Name != "System")
 827                                                 evaluator.ReferenceAssembly (a);
 828                                 }
 829
 830                                 RunRepl (s);
 831                         } finally {
 832                                 AppDomain.CurrentDomain.AssemblyLoad -= AssemblyLoaded;
 833                                 client.Close ();
 834                                 interrupt_client.Close ();
 835                                 Console.WriteLine ("csharp-agent: disconnected.");
 836                         }
 837                 }
 838
 839                 void AssemblyLoaded (object sender, AssemblyLoadEventArgs e)
 840                 {
 841                         evaluator.ReferenceAssembly (e.LoadedAssembly);
 842                 }
 843
 844                 public void RunRepl (NetworkStream s)
 845                 {
 846                         string input = null;
 847
 848                         while (!InteractiveBase.QuitRequested) {
 849                                 try {
 850                                         string error_string;
 851                                         StringWriter error_output = (StringWriter)stderr;
 852
 853                                         string line = s.GetString ();
 854
 855                                         bool result_set;
 856                                         object result;
 857
 858                                         if (input == null)
 859                                                 input = line;
 860                                         else
 861                                                 input = input + "\n" + line;
 862
 863                                         try {
 864                                                 input = evaluator.Evaluate (input, out result, out result_set);
 865                                         } catch (Exception e) {
 866                                                 s.WriteByte ((byte) AgentStatus.ERROR);
 867                                                 s.WriteString (e.ToString ());
 868                                                 s.WriteByte ((byte) AgentStatus.RESULT_NOT_SET);
 869                                                 continue;
 870                                         }
 871
 872                                         if (input != null){
 873                                                 s.WriteByte ((byte) AgentStatus.PARTIAL_INPUT);
 874                                                 continue;
 875                                         }
 876
 877                                         // Send warnings and errors back
 878                                         error_string = error_output.ToString ();
 879                                         if (error_string.Length != 0){
 880                                                 s.WriteByte ((byte) AgentStatus.ERROR);
 881                                                 s.WriteString (error_output.ToString ());
 882                                                 error_output.GetStringBuilder ().Clear ();
 883                                         }
 884
 885                                         if (result_set){
 886                                                 s.WriteByte ((byte) AgentStatus.RESULT_SET);
 887                                                 StringWriter sr = new StringWriter ();
 888                                                 CSharpShell.PrettyPrint (sr, result);
 889                                                 s.WriteString (sr.ToString ());
 890                                         } else {
 891                                                 s.WriteByte ((byte) AgentStatus.RESULT_NOT_SET);
 892                                         }
 893                                 } catch (IOException) {
 894                                         break;
 895                                 } catch (Exception e){
 896                                         Console.WriteLine (e);
 897                                 }
 898                         }
 899                 }
 900         }
 901
 902         public class UnixUtils {
 903                 [System.Runtime.InteropServices.DllImport ("libc", EntryPoint="isatty")]
 904                 extern static int _isatty (int fd);
 905
 906                 public static bool isatty (int fd)
 907                 {
 908                         try {
 909                                 return _isatty (fd) == 1;
 910                         } catch {
 911                                 return false;
 912                         }
 913                 }
 914         }
 915 #endif
 916 }
 917
 918 namespace Mono.Management
 919 {
 920         interface IVirtualMachine {
 921                 void LoadAgent (string filename, string args);
 922         }
 923 }
 924