mcs/mcs/cs-tokenizer.cs

   1 //
   2 // cs-tokenizer.cs: The Tokenizer for the C# compiler
   3 //                  This also implements the preprocessor
   4 //
   5 // Author: Miguel de Icaza (miguel@gnu.org)
   6 //
   7 // Licensed under the terms of the GNU GPL
   8 //
   9 // (C) 2001, 2002 Ximian, Inc (http://www.ximian.com)
  10 // (C) 2004 Novell, Inc
  11 //
  12
  13 /*
  14  * TODO:
  15  *   Make sure we accept the proper Unicode ranges, per the spec.
  16  *   Report error 1032
  17 */
  18
  19 using System;
  20 using System.Text;
  21 using System.Collections;
  22 using System.IO;
  23 using System.Globalization;
  24 using System.Reflection;
  25
  26 namespace Mono.CSharp
  27 {
  28         /// <summary>
  29         ///    Tokenizer for C# source code.
  30         /// </summary>
  31
  32         public class Tokenizer : yyParser.yyInput
  33         {
  34                 SeekableStreamReader reader;
  35                 public SourceFile ref_name;
  36                 public SourceFile file_name;
  37                 public int ref_line = 1;
  38                 public int line = 1;
  39                 public int col = 1;
  40                 public int current_token;
  41                 bool handle_get_set = false;
  42                 bool handle_remove_add = false;
  43                 bool handle_assembly = false;
  44
  45                 //
  46                 // XML documentation buffer. The save point is used to divide
  47                 // comments on types and comments on members.
  48                 //
  49                 StringBuilder xml_comment_buffer;
  50
  51                 //
  52                 // See comment on XmlCommentState enumeration.
  53                 //
  54                 XmlCommentState xmlDocState = XmlCommentState.Allowed;
  55
  56                 //
  57                 // Whether tokens have been seen on this line
  58                 //
  59                 bool tokens_seen = false;
  60
  61                 //
  62                 // Whether a token has been seen on the file
  63                 // This is needed because `define' is not allowed to be used
  64                 // after a token has been seen.
  65                 //
  66                 bool any_token_seen = false;
  67
  68                 static Hashtable tokenValues;
  69
  70                 private static Hashtable TokenValueName
  71                 {
  72                         get {
  73                                 if (tokenValues == null)
  74                                         tokenValues = GetTokenValueNameHash ();
  75
  76                                 return tokenValues;
  77                         }
  78                 }
  79
  80                 private static Hashtable GetTokenValueNameHash ()
  81                 {
  82                         Type t = typeof (Token);
  83                         FieldInfo [] fields = t.GetFields ();
  84                         Hashtable hash = new Hashtable ();
  85                         foreach (FieldInfo field in fields) {
  86                                 if (field.IsLiteral && field.IsStatic && field.FieldType == typeof (int))
  87                                         hash.Add (field.GetValue (null), field.Name);
  88                         }
  89                         return hash;
  90                 }
  91
  92                 //
  93                 // Returns a verbose representation of the current location
  94                 //
  95                 public string location {
  96                         get {
  97                                 string det;
  98
  99                                 if (current_token == Token.ERROR)
 100                                         det = "detail: " + error_details;
 101                                 else
 102                                         det = "";
 103
 104                                 // return "Line:     "+line+" Col: "+col + "\n" +
 105                                 //       "VirtLine: "+ref_line +
 106                                 //       " Token: "+current_token + " " + det;
 107                                 string current_token_name = TokenValueName [current_token] as string;
 108                                 if (current_token_name == null)
 109                                         current_token_name = current_token.ToString ();
 110
 111                                 return String.Format ("{0} ({1},{2}), Token: {3} {4}", ref_name.Name,
 112                                                                                        ref_line,
 113                                                                                        col,
 114                                                                                        current_token_name,
 115                                                                                        det);
 116                         }
 117                 }
 118
 119                 public bool PropertyParsing {
 120                         get {
 121                                 return handle_get_set;
 122                         }
 123
 124                         set {
 125                                 handle_get_set = value;
 126                         }
 127                 }
 128
 129                 public bool AssemblyTargetParsing {
 130                         get {
 131                                 return handle_assembly;
 132                         }
 133
 134                         set {
 135                                 handle_assembly = value;
 136                         }
 137                 }
 138
 139                 public bool EventParsing {
 140                         get {
 141                                 return handle_remove_add;
 142                         }
 143
 144                         set {
 145                                 handle_remove_add = value;
 146                         }
 147                 }
 148
 149                 public XmlCommentState doc_state {
 150                         get { return xmlDocState; }
 151                         set {
 152                                 if (value == XmlCommentState.Allowed) {
 153                                         check_incorrect_doc_comment ();
 154                                         consume_doc_comment ();
 155                                 }
 156                                 xmlDocState = value;
 157                         }
 158                 }
 159
 160
 161                 //
 162                 // Class variables
 163                 //
 164                 static CharArrayHashtable[] keywords;
 165                 static NumberStyles styles;
 166                 static NumberFormatInfo csharp_format_info;
 167
 168                 //
 169                 // Values for the associated token returned
 170                 //
 171                 int putback_char;
 172                 Object val;
 173
 174                 //
 175                 // Pre-processor
 176                 //
 177                 Hashtable defines;
 178
 179                 const int TAKING        = 1;
 180                 const int TAKEN_BEFORE  = 2;
 181                 const int ELSE_SEEN     = 4;
 182                 const int PARENT_TAKING = 8;
 183                 const int REGION        = 16;
 184
 185                 //
 186                 // pre-processor if stack state:
 187                 //
 188                 Stack ifstack;
 189
 190                 static System.Text.StringBuilder string_builder;
 191
 192                 const int max_id_size = 512;
 193                 static char [] id_builder = new char [max_id_size];
 194
 195                 static CharArrayHashtable [] identifiers = new CharArrayHashtable [max_id_size + 1];
 196
 197                 const int max_number_size = 128;
 198                 static char [] number_builder = new char [max_number_size];
 199                 static int number_pos;
 200
 201                 //
 202                 // Details about the error encoutered by the tokenizer
 203                 //
 204                 string error_details;
 205
 206                 public string error {
 207                         get {
 208                                 return error_details;
 209                         }
 210                 }
 211
 212                 public int Line {
 213                         get {
 214                                 return ref_line;
 215                         }
 216                 }
 217
 218                 public int Col {
 219                         get {
 220                                 return col;
 221                         }
 222                 }
 223
 224                 static void AddKeyword (string kw, int token) {
 225                         if (keywords [kw.Length] == null) {
 226                                 keywords [kw.Length] = new CharArrayHashtable (kw.Length);
 227                         }
 228                         keywords [kw.Length] [kw.ToCharArray ()] = token;
 229                 }
 230
 231                 static void InitTokens ()
 232                 {
 233                         keywords = new CharArrayHashtable [64];
 234
 235                         AddKeyword ("__arglist", Token.ARGLIST);
 236                         AddKeyword ("abstract", Token.ABSTRACT);
 237                         AddKeyword ("as", Token.AS);
 238                         AddKeyword ("add", Token.ADD);
 239                         AddKeyword ("assembly", Token.ASSEMBLY);
 240                         AddKeyword ("base", Token.BASE);
 241                         AddKeyword ("bool", Token.BOOL);
 242                         AddKeyword ("break", Token.BREAK);
 243                         AddKeyword ("byte", Token.BYTE);
 244                         AddKeyword ("case", Token.CASE);
 245                         AddKeyword ("catch", Token.CATCH);
 246                         AddKeyword ("char", Token.CHAR);
 247                         AddKeyword ("checked", Token.CHECKED);
 248                         AddKeyword ("class", Token.CLASS);
 249                         AddKeyword ("const", Token.CONST);
 250                         AddKeyword ("continue", Token.CONTINUE);
 251                         AddKeyword ("decimal", Token.DECIMAL);
 252                         AddKeyword ("default", Token.DEFAULT);
 253                         AddKeyword ("delegate", Token.DELEGATE);
 254                         AddKeyword ("do", Token.DO);
 255                         AddKeyword ("double", Token.DOUBLE);
 256                         AddKeyword ("else", Token.ELSE);
 257                         AddKeyword ("enum", Token.ENUM);
 258                         AddKeyword ("event", Token.EVENT);
 259                         AddKeyword ("explicit", Token.EXPLICIT);
 260                         AddKeyword ("extern", Token.EXTERN);
 261                         AddKeyword ("false", Token.FALSE);
 262                         AddKeyword ("finally", Token.FINALLY);
 263                         AddKeyword ("fixed", Token.FIXED);
 264                         AddKeyword ("float", Token.FLOAT);
 265                         AddKeyword ("for", Token.FOR);
 266                         AddKeyword ("foreach", Token.FOREACH);
 267                         AddKeyword ("goto", Token.GOTO);
 268                         AddKeyword ("get", Token.GET);
 269                         AddKeyword ("if", Token.IF);
 270                         AddKeyword ("implicit", Token.IMPLICIT);
 271                         AddKeyword ("in", Token.IN);
 272                         AddKeyword ("int", Token.INT);
 273                         AddKeyword ("interface", Token.INTERFACE);
 274                         AddKeyword ("internal", Token.INTERNAL);
 275                         AddKeyword ("is", Token.IS);
 276                         AddKeyword ("lock", Token.LOCK);
 277                         AddKeyword ("long", Token.LONG);
 278                         AddKeyword ("namespace", Token.NAMESPACE);
 279                         AddKeyword ("new", Token.NEW);
 280                         AddKeyword ("null", Token.NULL);
 281                         AddKeyword ("object", Token.OBJECT);
 282                         AddKeyword ("operator", Token.OPERATOR);
 283                         AddKeyword ("out", Token.OUT);
 284                         AddKeyword ("override", Token.OVERRIDE);
 285                         AddKeyword ("params", Token.PARAMS);
 286                         AddKeyword ("private", Token.PRIVATE);
 287                         AddKeyword ("protected", Token.PROTECTED);
 288                         AddKeyword ("public", Token.PUBLIC);
 289                         AddKeyword ("readonly", Token.READONLY);
 290                         AddKeyword ("ref", Token.REF);
 291                         AddKeyword ("remove", Token.REMOVE);
 292                         AddKeyword ("return", Token.RETURN);
 293                         AddKeyword ("sbyte", Token.SBYTE);
 294                         AddKeyword ("sealed", Token.SEALED);
 295                         AddKeyword ("set", Token.SET);
 296                         AddKeyword ("short", Token.SHORT);
 297                         AddKeyword ("sizeof", Token.SIZEOF);
 298                         AddKeyword ("stackalloc", Token.STACKALLOC);
 299                         AddKeyword ("static", Token.STATIC);
 300                         AddKeyword ("string", Token.STRING);
 301                         AddKeyword ("struct", Token.STRUCT);
 302                         AddKeyword ("switch", Token.SWITCH);
 303                         AddKeyword ("this", Token.THIS);
 304                         AddKeyword ("throw", Token.THROW);
 305                         AddKeyword ("true", Token.TRUE);
 306                         AddKeyword ("try", Token.TRY);
 307                         AddKeyword ("typeof", Token.TYPEOF);
 308                         AddKeyword ("uint", Token.UINT);
 309                         AddKeyword ("ulong", Token.ULONG);
 310                         AddKeyword ("unchecked", Token.UNCHECKED);
 311                         AddKeyword ("unsafe", Token.UNSAFE);
 312                         AddKeyword ("ushort", Token.USHORT);
 313                         AddKeyword ("using", Token.USING);
 314                         AddKeyword ("virtual", Token.VIRTUAL);
 315                         AddKeyword ("void", Token.VOID);
 316                         AddKeyword ("volatile", Token.VOLATILE);
 317                         AddKeyword ("while", Token.WHILE);
 318                         AddKeyword ("partial", Token.PARTIAL);
 319                 }
 320
 321                 //
 322                 // Class initializer
 323                 //
 324                 static Tokenizer ()
 325                 {
 326                         InitTokens ();
 327                         csharp_format_info = NumberFormatInfo.InvariantInfo;
 328                         styles = NumberStyles.Float;
 329
 330                         string_builder = new System.Text.StringBuilder ();
 331                 }
 332
 333                 int GetKeyword (char[] id, int id_len)
 334                 {
 335                         /*
 336                          * Keywords are stored in an array of hashtables grouped by their
 337                          * length.
 338                          */
 339
 340                         if ((id_len >= keywords.Length) || (keywords [id_len] == null))
 341                                 return -1;
 342                         object o = keywords [id_len] [id];
 343
 344                         if (o == null)
 345                                 return -1;
 346
 347                         int res = (int) o;
 348
 349                         if (handle_get_set == false && (res == Token.GET || res == Token.SET))
 350                                 return -1;
 351                         if (handle_remove_add == false && (res == Token.REMOVE || res == Token.ADD))
 352                                 return -1;
 353                         if (handle_assembly == false && res == Token.ASSEMBLY)
 354                                 return -1;
 355
 356                         return res;
 357
 358                 }
 359
 360                 public Location Location {
 361                         get {
 362                                 return new Location (ref_line);
 363                         }
 364                 }
 365
 366                 void define (string def)
 367                 {
 368                         if (!RootContext.AllDefines.Contains (def)){
 369                                 RootContext.AllDefines [def] = true;
 370                         }
 371                         if (defines.Contains (def))
 372                                 return;
 373                         defines [def] = true;
 374                 }
 375
 376                 public Tokenizer (SeekableStreamReader input, SourceFile file, ArrayList defs)
 377                 {
 378                         this.ref_name = file;
 379                         this.file_name = file;
 380                         reader = input;
 381
 382                         putback_char = -1;
 383
 384                         if (defs != null){
 385                                 defines = new Hashtable ();
 386                                 foreach (string def in defs)
 387                                         define (def);
 388                         }
 389
 390                         xml_comment_buffer = new StringBuilder ();
 391
 392                         //
 393                         // FIXME: This could be `Location.Push' but we have to
 394                         // find out why the MS compiler allows this
 395                         //
 396                         Mono.CSharp.Location.Push (file);
 397                 }
 398
 399                 public static void Cleanup () {
 400                         identifiers = null;
 401                 }
 402
 403                 static bool is_identifier_start_character (char c)
 404                 {
 405                         return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '_' || Char.IsLetter (c);
 406                 }
 407
 408                 static bool is_identifier_part_character (char c)
 409                 {
 410                         return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_' || (c >= '0' && c <= '9') || Char.IsLetter (c);
 411                 }
 412
 413                 public static bool IsValidIdentifier (string s)
 414                 {
 415                         if (s == null || s.Length == 0)
 416                                 return false;
 417
 418                         if (!is_identifier_start_character (s [0]))
 419                                 return false;
 420
 421                         for (int i = 1; i < s.Length; i ++)
 422                                 if (! is_identifier_part_character (s [i]))
 423                                         return false;
 424
 425                         return true;
 426                 }
 427
 428                 int is_punct (char c, ref bool doread)
 429                 {
 430                         int d;
 431                         int t;
 432
 433                         doread = false;
 434
 435                         switch (c){
 436                         case '{':
 437                                 return Token.OPEN_BRACE;
 438                         case '}':
 439                                 return Token.CLOSE_BRACE;
 440                         case '[':
 441                                 // To block doccomment inside attribute declaration.
 442                                 if (doc_state == XmlCommentState.Allowed)
 443                                         doc_state = XmlCommentState.NotAllowed;
 444                                 return Token.OPEN_BRACKET;
 445                         case ']':
 446                                 return Token.CLOSE_BRACKET;
 447                         case '(':
 448                                 return Token.OPEN_PARENS;
 449                         case ')': {
 450                                 if (deambiguate_close_parens == 0)
 451                                         return Token.CLOSE_PARENS;
 452
 453                                 --deambiguate_close_parens;
 454
 455                                 // Save current position and parse next token.
 456                                 int old = reader.Position;
 457                                 int new_token = token ();
 458                                 reader.Position = old;
 459                                 putback_char = -1;
 460
 461                                 if (new_token == Token.OPEN_PARENS)
 462                                         return Token.CLOSE_PARENS_OPEN_PARENS;
 463                                 else if (new_token == Token.MINUS)
 464                                         return Token.CLOSE_PARENS_MINUS;
 465                                 else if (IsCastToken (new_token))
 466                                         return Token.CLOSE_PARENS_CAST;
 467                                 else
 468                                         return Token.CLOSE_PARENS_NO_CAST;
 469                         }
 470
 471                         case ',':
 472                                 return Token.COMMA;
 473                         case ':':
 474                                 return Token.COLON;
 475                         case ';':
 476                                 return Token.SEMICOLON;
 477                         case '~':
 478                                 return Token.TILDE;
 479                         case '?':
 480                                 return Token.INTERR;
 481                         }
 482
 483                         d = peekChar ();
 484                         if (c == '+'){
 485
 486                                 if (d == '+')
 487                                         t = Token.OP_INC;
 488                                 else if (d == '=')
 489                                         t = Token.OP_ADD_ASSIGN;
 490                                 else
 491                                         return Token.PLUS;
 492                                 doread = true;
 493                                 return t;
 494                         }
 495                         if (c == '-'){
 496                                 if (d == '-')
 497                                         t = Token.OP_DEC;
 498                                 else if (d == '=')
 499                                         t = Token.OP_SUB_ASSIGN;
 500                                 else if (d == '>')
 501                                         t = Token.OP_PTR;
 502                                 else
 503                                         return Token.MINUS;
 504                                 doread = true;
 505                                 return t;
 506                         }
 507
 508                         if (c == '!'){
 509                                 if (d == '='){
 510                                         doread = true;
 511                                         return Token.OP_NE;
 512                                 }
 513                                 return Token.BANG;
 514                         }
 515
 516                         if (c == '='){
 517                                 if (d == '='){
 518                                         doread = true;
 519                                         return Token.OP_EQ;
 520                                 }
 521                                 return Token.ASSIGN;
 522                         }
 523
 524                         if (c == '&'){
 525                                 if (d == '&'){
 526                                         doread = true;
 527                                         return Token.OP_AND;
 528                                 } else if (d == '='){
 529                                         doread = true;
 530                                         return Token.OP_AND_ASSIGN;
 531                                 }
 532                                 return Token.BITWISE_AND;
 533                         }
 534
 535                         if (c == '|'){
 536                                 if (d == '|'){
 537                                         doread = true;
 538                                         return Token.OP_OR;
 539                                 } else if (d == '='){
 540                                         doread = true;
 541                                         return Token.OP_OR_ASSIGN;
 542                                 }
 543                                 return Token.BITWISE_OR;
 544                         }
 545
 546                         if (c == '*'){
 547                                 if (d == '='){
 548                                         doread = true;
 549                                         return Token.OP_MULT_ASSIGN;
 550                                 }
 551                                 return Token.STAR;
 552                         }
 553
 554                         if (c == '/'){
 555                                 if (d == '='){
 556                                         doread = true;
 557                                         return Token.OP_DIV_ASSIGN;
 558                                 }
 559                                 return Token.DIV;
 560                         }
 561
 562                         if (c == '%'){
 563                                 if (d == '='){
 564                                         doread = true;
 565                                         return Token.OP_MOD_ASSIGN;
 566                                 }
 567                                 return Token.PERCENT;
 568                         }
 569
 570                         if (c == '^'){
 571                                 if (d == '='){
 572                                         doread = true;
 573                                         return Token.OP_XOR_ASSIGN;
 574                                 }
 575                                 return Token.CARRET;
 576                         }
 577
 578                         if (c == '<'){
 579                                 if (d == '<'){
 580                                         getChar ();
 581                                         d = peekChar ();
 582
 583                                         if (d == '='){
 584                                                 doread = true;
 585                                                 return Token.OP_SHIFT_LEFT_ASSIGN;
 586                                         }
 587                                         return Token.OP_SHIFT_LEFT;
 588                                 } else if (d == '='){
 589                                         doread = true;
 590                                         return Token.OP_LE;
 591                                 }
 592                                 return Token.OP_LT;
 593                         }
 594
 595                         if (c == '>'){
 596                                 if (d == '>'){
 597                                         getChar ();
 598                                         d = peekChar ();
 599
 600                                         if (d == '='){
 601                                                 doread = true;
 602                                                 return Token.OP_SHIFT_RIGHT_ASSIGN;
 603                                         }
 604                                         return Token.OP_SHIFT_RIGHT;
 605                                 } else if (d == '='){
 606                                         doread = true;
 607                                         return Token.OP_GE;
 608                                 }
 609                                 return Token.OP_GT;
 610                         }
 611                         return Token.ERROR;
 612                 }
 613
 614                 int deambiguate_close_parens = 0;
 615
 616                 public void Deambiguate_CloseParens ()
 617                 {
 618                         putback (')');
 619                         deambiguate_close_parens++;
 620                 }
 621
 622                 void Error_NumericConstantTooLong ()
 623                 {
 624                         Report.Error (1021, Location, "Numeric constant too long");
 625                 }
 626
 627                 bool decimal_digits (int c)
 628                 {
 629                         int d;
 630                         bool seen_digits = false;
 631
 632                         if (c != -1){
 633                                 if (number_pos == max_number_size)
 634                                         Error_NumericConstantTooLong ();
 635                                 number_builder [number_pos++] = (char) c;
 636                         }
 637
 638                         //
 639                         // We use peekChar2, because decimal_digits needs to do a
 640                         // 2-character look-ahead (5.ToString for example).
 641                         //
 642                         while ((d = peekChar2 ()) != -1){
 643                                 if (d >= '0' && d <= '9'){
 644                                         if (number_pos == max_number_size)
 645                                                 Error_NumericConstantTooLong ();
 646                                         number_builder [number_pos++] = (char) d;
 647                                         getChar ();
 648                                         seen_digits = true;
 649                                 } else
 650                                         break;
 651                         }
 652
 653                         return seen_digits;
 654                 }
 655
 656                 bool is_hex (int e)
 657                 {
 658                         return (e >= '0' && e <= '9') || (e >= 'A' && e <= 'F') || (e >= 'a' && e <= 'f');
 659                 }
 660
 661                 void hex_digits (int c)
 662                 {
 663                         if (c != -1)
 664                                 number_builder [number_pos++] = (char) c;
 665
 666                 }
 667
 668                 int real_type_suffix (int c)
 669                 {
 670                         int t;
 671
 672                         switch (c){
 673                         case 'F': case 'f':
 674                                 t =  Token.LITERAL_FLOAT;
 675                                 break;
 676                         case 'D': case 'd':
 677                                 t = Token.LITERAL_DOUBLE;
 678                                 break;
 679                         case 'M': case 'm':
 680                                  t= Token.LITERAL_DECIMAL;
 681                                 break;
 682                         default:
 683                                 return Token.NONE;
 684                         }
 685                         return t;
 686                 }
 687
 688                 int integer_type_suffix (ulong ul, int c)
 689                 {
 690                         bool is_unsigned = false;
 691                         bool is_long = false;
 692
 693                         if (c != -1){
 694                                 bool scanning = true;
 695                                 do {
 696                                         switch (c){
 697                                         case 'U': case 'u':
 698                                                 if (is_unsigned)
 699                                                         scanning = false;
 700                                                 is_unsigned = true;
 701                                                 getChar ();
 702                                                 break;
 703
 704                                         case 'l':
 705                                                 if (!is_unsigned && (RootContext.WarningLevel >= 4)){
 706                                                         //
 707                                                         // if we have not seen anything in between
 708                                                         // report this error
 709                                                         //
 710                                                         Report.Warning (78, Location, "The 'l' suffix is easily confused with the digit '1' (use 'L' for clarity)");
 711                                                 }
 712                                                 //
 713                                                 // This goto statement causes the MS CLR 2.0 beta 1 csc to report an error, so
 714                                                 // work around that.
 715                                                 //
 716                                                 //goto case 'L';
 717                                                 if (is_long)
 718                                                         scanning = false;
 719                                                 is_long = true;
 720                                                 getChar ();
 721                                                 break;
 722
 723                                         case 'L':
 724                                                 if (is_long)
 725                                                         scanning = false;
 726                                                 is_long = true;
 727                                                 getChar ();
 728                                                 break;
 729
 730                                         default:
 731                                                 scanning = false;
 732                                                 break;
 733                                         }
 734                                         c = peekChar ();
 735                                 } while (scanning);
 736                         }
 737
 738                         if (is_long && is_unsigned){
 739                                 val = ul;
 740                                 return Token.LITERAL_INTEGER;
 741                         } else if (is_unsigned){
 742                                 // uint if possible, or ulong else.
 743
 744                                 if ((ul & 0xffffffff00000000) == 0)
 745                                         val = (uint) ul;
 746                                 else
 747                                         val = ul;
 748                         } else if (is_long){
 749                                 // long if possible, ulong otherwise
 750                                 if ((ul & 0x8000000000000000) != 0)
 751                                         val = ul;
 752                                 else
 753                                         val = (long) ul;
 754                         } else {
 755                                 // int, uint, long or ulong in that order
 756                                 if ((ul & 0xffffffff00000000) == 0){
 757                                         uint ui = (uint) ul;
 758
 759                                         if ((ui & 0x80000000) != 0)
 760                                                 val = ui;
 761                                         else
 762                                                 val = (int) ui;
 763                                 } else {
 764                                         if ((ul & 0x8000000000000000) != 0)
 765                                                 val = ul;
 766                                         else
 767                                                 val = (long) ul;
 768                                 }
 769                         }
 770                         return Token.LITERAL_INTEGER;
 771                 }
 772
 773                 //
 774                 // given `c' as the next char in the input decide whether
 775                 // we need to convert to a special type, and then choose
 776                 // the best representation for the integer
 777                 //
 778                 int adjust_int (int c)
 779                 {
 780                         try {
 781                                 if (number_pos > 9){
 782                                         ulong ul = (uint) (number_builder [0] - '0');
 783
 784                                         for (int i = 1; i < number_pos; i++){
 785                                                 ul = checked ((ul * 10) + ((uint)(number_builder [i] - '0')));
 786                                         }
 787                                         return integer_type_suffix (ul, c);
 788                                 } else {
 789                                         uint ui = (uint) (number_builder [0] - '0');
 790
 791                                         for (int i = 1; i < number_pos; i++){
 792                                                 ui = checked ((ui * 10) + ((uint)(number_builder [i] - '0')));
 793                                         }
 794                                         return integer_type_suffix (ui, c);
 795                                 }
 796                         } catch (OverflowException) {
 797                                 error_details = "Integral constant is too large";
 798                                 Report.Error (1021, Location, error_details);
 799                                 val = 0ul;
 800                                 return Token.LITERAL_INTEGER;
 801                         }
 802                 }
 803
 804                 int adjust_real (int t)
 805                 {
 806                         string s = new String (number_builder, 0, number_pos);
 807
 808                         switch (t){
 809                         case Token.LITERAL_DECIMAL:
 810                                 try {
 811                                         val = System.Decimal.Parse (s, styles, csharp_format_info);
 812                                 } catch (OverflowException) {
 813                                         val = 0m;
 814                                         error_details = "Floating-point constant is outside the range of the type 'decimal'";
 815                                         Report.Error (594, Location, error_details);
 816                                 }
 817                                 break;
 818                         case Token.LITERAL_FLOAT:
 819                                 try {
 820                                         val = (float) System.Double.Parse (s, styles, csharp_format_info);
 821                                 } catch (OverflowException) {
 822                                         val = 0.0f;
 823                                         error_details = "Floating-point constant is outside the range of the type 'float'";
 824                                         Report.Error (594, Location, error_details);
 825                                 }
 826                                 break;
 827
 828                         case Token.LITERAL_DOUBLE:
 829                         case Token.NONE:
 830                                 t = Token.LITERAL_DOUBLE;
 831                                 try {
 832                                         val = System.Double.Parse (s, styles, csharp_format_info);
 833                                 } catch (OverflowException) {
 834                                         val = 0.0;
 835                                         error_details = "Floating-point constant is outside the range of the type 'double'";
 836                                         Report.Error (594, Location, error_details);
 837                                 }
 838                                 break;
 839                         }
 840                         return t;
 841                 }
 842
 843                 int handle_hex ()
 844                 {
 845                         int d;
 846                         ulong ul;
 847
 848                         getChar ();
 849                         while ((d = peekChar ()) != -1){
 850                                 if (is_hex (d)){
 851                                         number_builder [number_pos++] = (char) d;
 852                                         getChar ();
 853                                 } else
 854                                         break;
 855                         }
 856
 857                         string s = new String (number_builder, 0, number_pos);
 858                         try {
 859                                 if (number_pos <= 8)
 860                                         ul = System.UInt32.Parse (s, NumberStyles.HexNumber);
 861                                 else
 862                                         ul = System.UInt64.Parse (s, NumberStyles.HexNumber);
 863                         } catch (OverflowException){
 864                                 error_details = "Integral constant is too large";
 865                                 Report.Error (1021, Location, error_details);
 866                                 val = 0ul;
 867                                 return Token.LITERAL_INTEGER;
 868                         }
 869                         catch (FormatException) {
 870                                 Report.Error (1013, Location, "Invalid number");
 871                                 val = 0ul;
 872                                 return Token.LITERAL_INTEGER;
 873                         }
 874
 875                         return integer_type_suffix (ul, peekChar ());
 876                 }
 877
 878                 //
 879                 // Invoked if we know we have .digits or digits
 880                 //
 881                 int is_number (int c)
 882                 {
 883                         bool is_real = false;
 884                         int type;
 885
 886                         number_pos = 0;
 887
 888                         if (c >= '0' && c <= '9'){
 889                                 if (c == '0'){
 890                                         int peek = peekChar ();
 891
 892                                         if (peek == 'x' || peek == 'X')
 893                                                 return handle_hex ();
 894                                 }
 895                                 decimal_digits (c);
 896                                 c = getChar ();
 897                         }
 898
 899                         //
 900                         // We need to handle the case of
 901                         // "1.1" vs "1.string" (LITERAL_FLOAT vs NUMBER DOT IDENTIFIER)
 902                         //
 903                         if (c == '.'){
 904                                 if (decimal_digits ('.')){
 905                                         is_real = true;
 906                                         c = getChar ();
 907                                 } else {
 908                                         putback ('.');
 909                                         number_pos--;
 910                                         return adjust_int (-1);
 911                                 }
 912                         }
 913
 914                         if (c == 'e' || c == 'E'){
 915                                 is_real = true;
 916                                 if (number_pos == max_number_size)
 917                                         Error_NumericConstantTooLong ();
 918                                 number_builder [number_pos++] = 'e';
 919                                 c = getChar ();
 920
 921                                 if (c == '+'){
 922                                         if (number_pos == max_number_size)
 923                                                 Error_NumericConstantTooLong ();
 924                                         number_builder [number_pos++] = '+';
 925                                         c = -1;
 926                                 } else if (c == '-') {
 927                                         if (number_pos == max_number_size)
 928                                                 Error_NumericConstantTooLong ();
 929                                         number_builder [number_pos++] = '-';
 930                                         c = -1;
 931                                 } else {
 932                                         if (number_pos == max_number_size)
 933                                                 Error_NumericConstantTooLong ();
 934                                         number_builder [number_pos++] = '+';
 935                                 }
 936
 937                                 decimal_digits (c);
 938                                 c = getChar ();
 939                         }
 940
 941                         type = real_type_suffix (c);
 942                         if (type == Token.NONE && !is_real){
 943                                 putback (c);
 944                                 return adjust_int (c);
 945                         } else
 946                                 is_real = true;
 947
 948                         if (type == Token.NONE){
 949                                 putback (c);
 950                         }
 951
 952                         if (is_real)
 953                                 return adjust_real (type);
 954
 955                         Console.WriteLine ("This should not be reached");
 956                         throw new Exception ("Is Number should never reach this point");
 957                 }
 958
 959                 //
 960                 // Accepts exactly count (4 or 8) hex, no more no less
 961                 //
 962                 int getHex (int count, out bool error)
 963                 {
 964                         int i;
 965                         int total = 0;
 966                         int c;
 967                         int top = count != -1 ? count : 4;
 968
 969                         getChar ();
 970                         error = false;
 971                         for (i = 0; i < top; i++){
 972                                 c = getChar ();
 973
 974                                 if (c >= '0' && c <= '9')
 975                                         c = (int) c - (int) '0';
 976                                 else if (c >= 'A' && c <= 'F')
 977                                         c = (int) c - (int) 'A' + 10;
 978                                 else if (c >= 'a' && c <= 'f')
 979                                         c = (int) c - (int) 'a' + 10;
 980                                 else {
 981                                         error = true;
 982                                         return 0;
 983                                 }
 984
 985                                 total = (total * 16) + c;
 986                                 if (count == -1){
 987                                         int p = peekChar ();
 988                                         if (p == -1)
 989                                                 break;
 990                                         if (!is_hex ((char)p))
 991                                                 break;
 992                                 }
 993                         }
 994                         return total;
 995                 }
 996
 997                 int escape (int c)
 998                 {
 999                         bool error;
1000                         int d;
1001                         int v;
1002
1003                         d = peekChar ();
1004                         if (c != '\\')
1005                                 return c;
1006
1007                         switch (d){
1008                         case 'a':
1009                                 v = '\a'; break;
1010                         case 'b':
1011                                 v = '\b'; break;
1012                         case 'n':
1013                                 v = '\n'; break;
1014                         case 't':
1015                                 v = '\t'; break;
1016                         case 'v':
1017                                 v = '\v'; break;
1018                         case 'r':
1019                                 v = '\r'; break;
1020                         case '\\':
1021                                 v = '\\'; break;
1022                         case 'f':
1023                                 v = '\f'; break;
1024                         case '0':
1025                                 v = 0; break;
1026                         case '"':
1027                                 v = '"'; break;
1028                         case '\'':
1029                                 v = '\''; break;
1030                         case 'x':
1031                                 v = getHex (-1, out error);
1032                                 if (error)
1033                                         goto default;
1034                                 return v;
1035                         case 'u':
1036                                 v = getHex (4, out error);
1037                                 if (error)
1038                                         goto default;
1039                                 return v;
1040                         case 'U':
1041                                 v = getHex (8, out error);
1042                                 if (error)
1043                                         goto default;
1044                                 return v;
1045                         default:
1046                                 Report.Error (1009, Location, "Unrecognized escape sequence in " + (char)d);
1047                                 return d;
1048                         }
1049                         getChar ();
1050                         return v;
1051                 }
1052
1053                 int getChar ()
1054                 {
1055                         if (putback_char != -1){
1056                                 int x = putback_char;
1057                                 putback_char = -1;
1058
1059                                 return x;
1060                         }
1061                         return reader.Read ();
1062                 }
1063
1064                 int peekChar ()
1065                 {
1066                         if (putback_char != -1)
1067                                 return putback_char;
1068                         putback_char = reader.Read ();
1069                         return putback_char;
1070                 }
1071
1072                 int peekChar2 ()
1073                 {
1074                         if (putback_char != -1)
1075                                 return putback_char;
1076                         return reader.Peek ();
1077                 }
1078
1079                 void putback (int c)
1080                 {
1081                         if (putback_char != -1){
1082                                 Console.WriteLine ("Col: " + col);
1083                                 Console.WriteLine ("Row: " + line);
1084                                 Console.WriteLine ("Name: " + ref_name.Name);
1085                                 Console.WriteLine ("Current [{0}] putting back [{1}]  ", putback_char, c);
1086                                 throw new Exception ("This should not happen putback on putback");
1087                         }
1088                         putback_char = c;
1089                 }
1090
1091                 public bool advance ()
1092                 {
1093                         return peekChar () != -1;
1094                 }
1095
1096                 public Object Value {
1097                         get {
1098                                 return val;
1099                         }
1100                 }
1101
1102                 public Object value ()
1103                 {
1104                         return val;
1105                 }
1106
1107                 bool IsCastToken (int token)
1108                 {
1109                         switch (token) {
1110                         case Token.BANG:
1111                         case Token.TILDE:
1112                         case Token.IDENTIFIER:
1113                         case Token.LITERAL_INTEGER:
1114                         case Token.LITERAL_FLOAT:
1115                         case Token.LITERAL_DOUBLE:
1116                         case Token.LITERAL_DECIMAL:
1117                         case Token.LITERAL_CHARACTER:
1118                         case Token.LITERAL_STRING:
1119                         case Token.BASE:
1120                         case Token.CHECKED:
1121                         case Token.FALSE:
1122                         case Token.FIXED:
1123                         case Token.NEW:
1124                         case Token.NULL:
1125                         case Token.SIZEOF:
1126                         case Token.THIS:
1127                         case Token.THROW:
1128                         case Token.TRUE:
1129                         case Token.TYPEOF:
1130                         case Token.UNCHECKED:
1131                         case Token.UNSAFE:
1132
1133                                 //
1134                                 // These can be part of a member access
1135                                 //
1136                         case Token.INT:
1137                         case Token.UINT:
1138                         case Token.SHORT:
1139                         case Token.USHORT:
1140                         case Token.LONG:
1141                         case Token.ULONG:
1142                         case Token.DOUBLE:
1143                         case Token.FLOAT:
1144                         case Token.CHAR:
1145                                 return true;
1146
1147                         default:
1148                                 return false;
1149                         }
1150                 }
1151
1152                 public int token ()
1153                 {
1154                         current_token = xtoken ();
1155                         return current_token;
1156                 }
1157
1158                 static StringBuilder static_cmd_arg = new System.Text.StringBuilder ();
1159
1160                 void get_cmd_arg (out string cmd, out string arg)
1161                 {
1162                         int c;
1163
1164                         tokens_seen = false;
1165                         arg = "";
1166                         static_cmd_arg.Length = 0;
1167
1168                         // skip over white space
1169                         while ((c = getChar ()) != -1 && (c != '\n') && ((c == '\r') || (c == ' ') || (c == '\t')))
1170                                 ;
1171
1172
1173                         while ((c != -1) && (c != '\n') && (c != ' ') && (c != '\t') && (c != '\r')){
1174                                 if (is_identifier_part_character ((char) c)){
1175                                         static_cmd_arg.Append ((char) c);
1176                                         c = getChar ();
1177                                 } else {
1178                                         putback (c);
1179                                         break;
1180                                 }
1181                         }
1182
1183                         cmd = static_cmd_arg.ToString ();
1184
1185                         if (c == '\n'){
1186                                 line++;
1187                                 ref_line++;
1188                                 return;
1189                         } else if (c == '\r')
1190                                 col = 0;
1191
1192                         // skip over white space
1193                         while ((c = getChar ()) != -1 && (c != '\n') && ((c == '\r') || (c == ' ') || (c == '\t')))
1194                                 ;
1195
1196                         if (c == '\n'){
1197                                 line++;
1198                                 ref_line++;
1199                                 return;
1200                         } else if (c == '\r'){
1201                                 col = 0;
1202                                 return;
1203                         }
1204
1205                         static_cmd_arg.Length = 0;
1206                         static_cmd_arg.Append ((char) c);
1207
1208                         while ((c = getChar ()) != -1 && (c != '\n') && (c != '\r')){
1209                                 static_cmd_arg.Append ((char) c);
1210                         }
1211
1212                         if (c == '\n'){
1213                                 line++;
1214                                 ref_line++;
1215                         } else if (c == '\r')
1216                                 col = 0;
1217                         arg = static_cmd_arg.ToString ().Trim ();
1218                 }
1219
1220                 //
1221                 // Handles the #line directive
1222                 //
1223                 bool PreProcessLine (string arg)
1224                 {
1225                         if (arg == "")
1226                                 return false;
1227
1228                         if (arg == "default"){
1229                                 ref_line = line;
1230                                 ref_name = file_name;
1231                                 Location.Push (ref_name);
1232                                 return true;
1233                         } else if (arg == "hidden"){
1234                                 //
1235                                 // We ignore #line hidden
1236                                 //
1237                                 return true;
1238                         }
1239
1240                         try {
1241                                 int pos;
1242
1243                                 if ((pos = arg.IndexOf (' ')) != -1 && pos != 0){
1244                                         ref_line = System.Int32.Parse (arg.Substring (0, pos));
1245                                         pos++;
1246
1247                                         char [] quotes = { '\"' };
1248
1249                                         string name = arg.Substring (pos). Trim (quotes);
1250                                         ref_name = Location.LookupFile (name);
1251                                         file_name.HasLineDirective = true;
1252                                         ref_name.HasLineDirective = true;
1253                                         Location.Push (ref_name);
1254                                 } else {
1255                                         ref_line = System.Int32.Parse (arg);
1256                                 }
1257                         } catch {
1258                                 return false;
1259                         }
1260
1261                         return true;
1262                 }
1263
1264                 //
1265                 // Handles #define and #undef
1266                 //
1267                 void PreProcessDefinition (bool is_define, string arg)
1268                 {
1269                         if (arg == "" || arg == "true" || arg == "false"){
1270                                 Report.Error (1001, Location, "Missing identifer to pre-processor directive");
1271                                 return;
1272                         }
1273
1274                         char[] whitespace = { ' ', '\t' };
1275                         if (arg.IndexOfAny (whitespace) != -1){
1276                                 Report.Error (1025, Location, "Single-line comment or end-of-line expected");
1277                                 return;
1278                         }
1279
1280                         if (!is_identifier_start_character (arg [0]))
1281                                 Report.Error (1001, Location, "Identifier expected: " + arg);
1282
1283                         foreach (char c in arg.Substring (1)){
1284                                 if (!is_identifier_part_character (c)){
1285                                         Report.Error (1001, Location, "Identifier expected: " + arg);
1286                                         return;
1287                                 }
1288                         }
1289
1290                         if (is_define){
1291                                 if (defines == null)
1292                                         defines = new Hashtable ();
1293                                 define (arg);
1294                         } else {
1295                                 if (defines == null)
1296                                         return;
1297                                 if (defines.Contains (arg))
1298                                         defines.Remove (arg);
1299                         }
1300                 }
1301
1302                 /// <summary>
1303                 /// Handles #pragma directive
1304                 /// </summary>
1305                 void PreProcessPragma (string arg)
1306                 {
1307                         const string disable = "warning disable";
1308                         const string restore = "warning restore";
1309
1310                         if (arg == disable) {
1311                                 Report.RegisterWarningRegion (Location).WarningDisable (line);
1312                                 return;
1313                         }
1314
1315                         if (arg == restore) {
1316                                 Report.RegisterWarningRegion (Location).WarningEnable (line);
1317                                 return;
1318                         }
1319
1320                         if (arg.StartsWith (disable)) {
1321                                 int[] codes = ParseNumbers (arg.Substring (disable.Length));
1322                                 foreach (int code in codes) {
1323                                         if (code != 0)
1324                                                 Report.RegisterWarningRegion (Location).WarningDisable (Location, code);
1325                                 }
1326                                 return;
1327                         }
1328
1329                         if (arg.StartsWith (restore)) {
1330                                 int[] codes = ParseNumbers (arg.Substring (restore.Length));
1331                                 foreach (int code in codes) {
1332                                         Report.RegisterWarningRegion (Location).WarningEnable (Location, code);
1333                                 }
1334                                 return;
1335                         }
1336
1337                         return;
1338                 }
1339
1340                 int[] ParseNumbers (string text)
1341                 {
1342                         string[] string_array = text.Split (',');
1343                         int[] values = new int [string_array.Length];
1344                         int index = 0;
1345                         foreach (string string_code in string_array) {
1346                                 try {
1347                                         values[index++] = int.Parse (string_code, System.Globalization.CultureInfo.InvariantCulture);
1348                                 }
1349                                 catch (FormatException) {
1350                                         Report.Warning (1692, Location, "Invalid number");
1351                                 }
1352                         }
1353                         return values;
1354                 }
1355
1356                 bool eval_val (string s)
1357                 {
1358                         if (s == "true")
1359                                 return true;
1360                         if (s == "false")
1361                                 return false;
1362
1363                         if (defines == null)
1364                                 return false;
1365                         if (defines.Contains (s))
1366                                 return true;
1367
1368                         return false;
1369                 }
1370
1371                 bool pp_primary (ref string s)
1372                 {
1373                         s = s.Trim ();
1374                         int len = s.Length;
1375
1376                         if (len > 0){
1377                                 char c = s [0];
1378
1379                                 if (c == '('){
1380                                         s = s.Substring (1);
1381                                         bool val = pp_expr (ref s);
1382                                         if (s.Length > 0 && s [0] == ')'){
1383                                                 s = s.Substring (1);
1384                                                 return val;
1385                                         }
1386                                         Error_InvalidDirective ();
1387                                         return false;
1388                                 }
1389
1390                                 if (is_identifier_start_character (c)){
1391                                         int j = 1;
1392
1393                                         while (j < len){
1394                                                 c = s [j];
1395
1396                                                 if (is_identifier_part_character (c)){
1397                                                         j++;
1398                                                         continue;
1399                                                 }
1400                                                 bool v = eval_val (s.Substring (0, j));
1401                                                 s = s.Substring (j);
1402                                                 return v;
1403                                         }
1404                                         bool vv = eval_val (s);
1405                                         s = "";
1406                                         return vv;
1407                                 }
1408                         }
1409                         Error_InvalidDirective ();
1410                         return false;
1411                 }
1412
1413                 bool pp_unary (ref string s)
1414                 {
1415                         s = s.Trim ();
1416                         int len = s.Length;
1417
1418                         if (len > 0){
1419                                 if (s [0] == '!'){
1420                                         if (len > 1 && s [1] == '='){
1421                                                 Error_InvalidDirective ();
1422                                                 return false;
1423                                         }
1424                                         s = s.Substring (1);
1425                                         return ! pp_primary (ref s);
1426                                 } else
1427                                         return pp_primary (ref s);
1428                         } else {
1429                                 Error_InvalidDirective ();
1430                                 return false;
1431                         }
1432                 }
1433
1434                 bool pp_eq (ref string s)
1435                 {
1436                         bool va = pp_unary (ref s);
1437
1438                         s = s.Trim ();
1439                         int len = s.Length;
1440                         if (len > 0){
1441                                 if (s [0] == '='){
1442                                         if (len > 2 && s [1] == '='){
1443                                                 s = s.Substring (2);
1444                                                 return va == pp_unary (ref s);
1445                                         } else {
1446                                                 Error_InvalidDirective ();
1447                                                 return false;
1448                                         }
1449                                 } else if (s [0] == '!' && len > 1 && s [1] == '='){
1450                                         s = s.Substring (2);
1451
1452                                         return va != pp_unary (ref s);
1453
1454                                 }
1455                         }
1456
1457                         return va;
1458
1459                 }
1460
1461                 bool pp_and (ref string s)
1462                 {
1463                         bool va = pp_eq (ref s);
1464
1465                         s = s.Trim ();
1466                         int len = s.Length;
1467                         if (len > 0){
1468                                 if (s [0] == '&'){
1469                                         if (len > 2 && s [1] == '&'){
1470                                                 s = s.Substring (2);
1471                                                 return (va & pp_eq (ref s));
1472                                         } else {
1473                                                 Error_InvalidDirective ();
1474                                                 return false;
1475                                         }
1476                                 }
1477                         }
1478                         return va;
1479                 }
1480
1481                 //
1482                 // Evaluates an expression for `#if' or `#elif'
1483                 //
1484                 bool pp_expr (ref string s)
1485                 {
1486                         bool va = pp_and (ref s);
1487                         s = s.Trim ();
1488                         int len = s.Length;
1489                         if (len > 0){
1490                                 char c = s [0];
1491
1492                                 if (c == '|'){
1493                                         if (len > 2 && s [1] == '|'){
1494                                                 s = s.Substring (2);
1495                                                 return va | pp_expr (ref s);
1496                                         } else {
1497                                                 Error_InvalidDirective ();
1498                                                 return false;
1499                                         }
1500                                 }
1501                         }
1502
1503                         return va;
1504                 }
1505
1506                 bool eval (string s)
1507                 {
1508                         bool v = pp_expr (ref s);
1509                         s = s.Trim ();
1510                         if (s.Length != 0){
1511                                 Error_InvalidDirective ();
1512                                 return false;
1513                         }
1514
1515                         return v;
1516                 }
1517
1518                 void Error_InvalidDirective ()
1519                 {
1520                         Report.Error (1517, Location, "Invalid pre-processor directive");
1521                 }
1522
1523                 void Error_UnexpectedDirective (string extra)
1524                 {
1525                         Report.Error (
1526                                 1028, Location,
1527                                 "Unexpected processor directive (" + extra + ")");
1528                 }
1529
1530                 void Error_TokensSeen ()
1531                 {
1532                         Report.Error (
1533                                 1032, Location,
1534                                 "Cannot define or undefine pre-processor symbols after a token in the file");
1535                 }
1536
1537                 //
1538                 // if true, then the code continues processing the code
1539                 // if false, the code stays in a loop until another directive is
1540                 // reached.
1541                 //
1542                 bool handle_preprocessing_directive (bool caller_is_taking)
1543                 {
1544                         string cmd, arg;
1545                         bool region_directive = false;
1546
1547                         get_cmd_arg (out cmd, out arg);
1548
1549                         // Eat any trailing whitespaces and single-line comments
1550                         if (arg.IndexOf ("//") != -1)
1551                                 arg = arg.Substring (0, arg.IndexOf ("//"));
1552                         arg = arg.TrimEnd (' ', '\t');
1553
1554                         //
1555                         // The first group of pre-processing instructions is always processed
1556                         //
1557                         switch (cmd){
1558                         case "pragma":
1559                                 if (RootContext.Version == LanguageVersion.ISO_1) {
1560                                         Report.FeatureIsNotStandardized (Location, "#pragma");
1561                                         return caller_is_taking;
1562                                 }
1563
1564                                 PreProcessPragma (arg);
1565                                 return caller_is_taking;
1566
1567                         case "line":
1568                                 if (!PreProcessLine (arg))
1569                                         Report.Error (
1570                                                 1576, Location,
1571                                                 "Argument to #line directive is missing or invalid");
1572                                 return caller_is_taking;
1573
1574                         case "region":
1575                                 region_directive = true;
1576                                 arg = "true";
1577                                 goto case "if";
1578
1579                         case "endregion":
1580                                 region_directive = true;
1581                                 goto case "endif";
1582
1583                         case "if":
1584                                 if (arg == ""){
1585                                         Error_InvalidDirective ();
1586                                         return true;
1587                                 }
1588                                 bool taking = false;
1589                                 if (ifstack == null)
1590                                         ifstack = new Stack ();
1591
1592                                 if (ifstack.Count == 0){
1593                                         taking = true;
1594                                 } else {
1595                                         int state = (int) ifstack.Peek ();
1596                                         if ((state & TAKING) != 0)
1597                                                 taking = true;
1598                                 }
1599
1600                                 if (eval (arg) && taking){
1601                                         int push = TAKING | TAKEN_BEFORE | PARENT_TAKING;
1602                                         if (region_directive)
1603                                                 push |= REGION;
1604                                         ifstack.Push (push);
1605                                         return true;
1606                                 } else {
1607                                         int push = (taking ? PARENT_TAKING : 0);
1608                                         if (region_directive)
1609                                                 push |= REGION;
1610                                         ifstack.Push (push);
1611                                         return false;
1612                                 }
1613
1614                         case "endif":
1615                                 if (ifstack == null || ifstack.Count == 0){
1616                                         Error_UnexpectedDirective ("no #if for this #endif");
1617                                         return true;
1618                                 } else {
1619                                         int pop = (int) ifstack.Pop ();
1620
1621                                         if (region_directive && ((pop & REGION) == 0))
1622                                                 Report.Error (1027, Location, "#endif directive expected");
1623                                         else if (!region_directive && ((pop & REGION) != 0))
1624                                                 Report.Error (1038, Location, "#endregion directive expected");
1625
1626                                         if (ifstack.Count == 0)
1627                                                 return true;
1628                                         else {
1629                                                 int state = (int) ifstack.Peek ();
1630
1631                                                 if ((state & TAKING) != 0)
1632                                                         return true;
1633                                                 else
1634                                                         return false;
1635                                         }
1636                                 }
1637
1638                         case "elif":
1639                                 if (ifstack == null || ifstack.Count == 0){
1640                                         Error_UnexpectedDirective ("no #if for this #elif");
1641                                         return true;
1642                                 } else {
1643                                         int state = (int) ifstack.Peek ();
1644
1645                                         if ((state & REGION) != 0) {
1646                                                 Report.Error (1038, Location, "#endregion directive expected");
1647                                                 return true;
1648                                         }
1649
1650                                         if ((state & ELSE_SEEN) != 0){
1651                                                 Error_UnexpectedDirective ("#elif not valid after #else");
1652                                                 return true;
1653                                         }
1654
1655                                         if ((state & (TAKEN_BEFORE | TAKING)) != 0)
1656                                                 return false;
1657
1658                                         if (eval (arg) && ((state & PARENT_TAKING) != 0)){
1659                                                 state = (int) ifstack.Pop ();
1660                                                 ifstack.Push (state | TAKING | TAKEN_BEFORE);
1661                                                 return true;
1662                                         } else
1663                                                 return false;
1664                                 }
1665
1666                         case "else":
1667                                 if (ifstack == null || ifstack.Count == 0){
1668                                         Report.Error (
1669                                                 1028, Location,
1670                                                 "Unexpected processor directive (no #if for this #else)");
1671                                         return true;
1672                                 } else {
1673                                         int state = (int) ifstack.Peek ();
1674
1675                                         if ((state & REGION) != 0) {
1676                                                 Report.Error (1038, Location, "#endregion directive expected");
1677                                                 return true;
1678                                         }
1679
1680                                         if ((state & ELSE_SEEN) != 0){
1681                                                 Error_UnexpectedDirective ("#else within #else");
1682                                                 return true;
1683                                         }
1684
1685                                         ifstack.Pop ();
1686
1687                                         bool ret;
1688                                         if ((state & TAKEN_BEFORE) == 0){
1689                                                 ret = ((state & PARENT_TAKING) != 0);
1690                                         } else
1691                                                 ret = false;
1692
1693                                         if (ret)
1694                                                 state |= TAKING;
1695                                         else
1696                                                 state &= ~TAKING;
1697
1698                                         ifstack.Push (state | ELSE_SEEN);
1699
1700                                         return ret;
1701                                 }
1702                         }
1703
1704                         //
1705                         // These are only processed if we are in a `taking' block
1706                         //
1707                         if (!caller_is_taking)
1708                                 return false;
1709
1710                         switch (cmd){
1711                         case "define":
1712                                 if (any_token_seen){
1713                                         Error_TokensSeen ();
1714                                         return true;
1715                                 }
1716                                 PreProcessDefinition (true, arg);
1717                                 return true;
1718
1719                         case "undef":
1720                                 if (any_token_seen){
1721                                         Error_TokensSeen ();
1722                                         return true;
1723                                 }
1724                                 PreProcessDefinition (false, arg);
1725                                 return true;
1726
1727                         case "error":
1728                                 Report.Error (1029, Location, "#error: '" + arg + "'");
1729                                 return true;
1730
1731                         case "warning":
1732                                 Report.Warning (1030, Location, "#warning: '{0}'", arg);
1733                                 return true;
1734                         }
1735
1736                         Report.Error (1024, Location, "Preprocessor directive expected (got: " + cmd + ")");
1737                         return true;
1738
1739                 }
1740
1741                 private int consume_string (bool quoted)
1742                 {
1743                         int c;
1744                         string_builder.Length = 0;
1745
1746                         while ((c = getChar ()) != -1){
1747                                 if (c == '"'){
1748                                         if (quoted && peekChar () == '"'){
1749                                                 string_builder.Append ((char) c);
1750                                                 getChar ();
1751                                                 continue;
1752                                         } else {
1753                                                 val = string_builder.ToString ();
1754                                                 return Token.LITERAL_STRING;
1755                                         }
1756                                 }
1757
1758                                 if (c == '\n'){
1759                                         if (!quoted)
1760                                                 Report.Error (1010, Location, "Newline in constant");
1761                                         line++;
1762                                         ref_line++;
1763                                         col = 0;
1764                                 } else
1765                                         col++;
1766
1767                                 if (!quoted){
1768                                         c = escape (c);
1769                                         if (c == -1)
1770                                                 return Token.ERROR;
1771                                 }
1772                                 string_builder.Append ((char) c);
1773                         }
1774
1775                         Report.Error (1039, Location, "Unterminated string literal");
1776                         return Token.EOF;
1777                 }
1778
1779                 private int consume_identifier (int s)
1780                 {
1781                         int res = consume_identifier (s, false);
1782
1783                         if (doc_state == XmlCommentState.Allowed)
1784                                 doc_state = XmlCommentState.NotAllowed;
1785                         switch (res) {
1786                         case Token.USING:
1787                         case Token.NAMESPACE:
1788                                 check_incorrect_doc_comment ();
1789                                 break;
1790                         }
1791
1792                         if (res == Token.PARTIAL) {
1793                                 // Save current position and parse next token.
1794                                 int old = reader.Position;
1795                                 int old_putback = putback_char;
1796
1797                                 putback_char = -1;
1798
1799                                 int next_token = token ();
1800                                 bool ok = (next_token == Token.CLASS) ||
1801                                         (next_token == Token.STRUCT) ||
1802                                         (next_token == Token.INTERFACE);
1803
1804                                 reader.Position = old;
1805                                 putback_char = old_putback;
1806
1807                                 if (ok)
1808                                         return res;
1809                                 else {
1810                                         val = "partial";
1811                                         return Token.IDENTIFIER;
1812                                 }
1813                         }
1814
1815                         return res;
1816                 }
1817
1818                 private int consume_identifier (int s, bool quoted)
1819                 {
1820                         int pos = 1;
1821                         int c;
1822
1823                         id_builder [0] = (char) s;
1824
1825                         while ((c = reader.Read ()) != -1) {
1826                                 if (is_identifier_part_character ((char) c)){
1827                                         if (pos == max_id_size){
1828                                                 Report.Error (645, Location, "Identifier too long (limit is 512 chars)");
1829                                                 return Token.ERROR;
1830                                         }
1831
1832                                         id_builder [pos++] = (char) c;
1833                                         putback_char = -1;
1834                                         col++;
1835                                 } else {
1836                                         putback_char = c;
1837                                         break;
1838                                 }
1839                         }
1840
1841                         //
1842                         // Optimization: avoids doing the keyword lookup
1843                         // on uppercase letters and _
1844                         //
1845                         if (!quoted && (s >= 'a' || s == '_')){
1846                                 int keyword = GetKeyword (id_builder, pos);
1847                                 if (keyword != -1)
1848                                         return keyword;
1849                         }
1850
1851                         //
1852                         // Keep identifiers in an array of hashtables to avoid needless
1853                         // allocations
1854                         //
1855
1856                         if (identifiers [pos] != null) {
1857                                 val = identifiers [pos][id_builder];
1858                                 if (val != null) {
1859                                         return Token.IDENTIFIER;
1860                                 }
1861                         }
1862                         else
1863                                 identifiers [pos] = new CharArrayHashtable (pos);
1864
1865                         val = new String (id_builder, 0, pos);
1866
1867                         char [] chars = new char [pos];
1868                         Array.Copy (id_builder, chars, pos);
1869
1870                         identifiers [pos] [chars] = val;
1871
1872                         return Token.IDENTIFIER;
1873                 }
1874
1875                 public int xtoken ()
1876                 {
1877                         int t;
1878                         bool doread = false;
1879                         int c;
1880
1881                         // Whether we have seen comments on the current line
1882                         bool comments_seen = false;
1883
1884                         val = null;
1885                         // optimization: eliminate col and implement #directive semantic correctly.
1886                         for (;(c = getChar ()) != -1; col++) {
1887                                 if (c == ' ')
1888                                         continue;
1889
1890                                 if (c == '\t') {
1891                                         col = (((col + 8) / 8) * 8) - 1;
1892                                         continue;
1893                                 }
1894
1895                                 if (c == ' ' || c == '\f' || c == '\v' || c == 0xa0)
1896                                         continue;
1897
1898                                 if (c == '\r') {
1899                                         if (peekChar () == '\n')
1900                                                 getChar ();
1901
1902                                         line++;
1903                                         ref_line++;
1904                                         col = 0;
1905                                         any_token_seen |= tokens_seen;
1906                                         tokens_seen = false;
1907                                         comments_seen = false;
1908                                         continue;
1909                                 }
1910
1911                                 // Handle double-slash comments.
1912                                 if (c == '/'){
1913                                         int d = peekChar ();
1914
1915                                         if (d == '/'){
1916                                                 getChar ();
1917                                                 if (RootContext.Documentation != null && peekChar () == '/') {
1918                                                         getChar ();
1919                                                         // Don't allow ////.
1920                                                         if ((d = peekChar ()) != '/') {
1921                                                                 if (doc_state == XmlCommentState.Allowed)
1922                                                                         handle_one_line_xml_comment ();
1923                                                                 else if (doc_state == XmlCommentState.NotAllowed)
1924                                                                         warn_incorrect_doc_comment ();
1925                                                         }
1926                                                 }
1927                                                 while ((d = getChar ()) != -1 && (d != '\n') && d != '\r')
1928                                                         col++;
1929                                                 if (d == '\n'){
1930                                                         line++;
1931                                                         ref_line++;
1932                                                         col = 0;
1933                                                 }
1934                                                 any_token_seen |= tokens_seen;
1935                                                 tokens_seen = false;
1936                                                 comments_seen = false;
1937                                                 continue;
1938                                         } else if (d == '*'){
1939                                                 getChar ();
1940                                                 bool docAppend = false;
1941                                                 if (RootContext.Documentation != null && peekChar () == '*') {
1942                                                         getChar ();
1943                                                         // But when it is /**/, just do nothing.
1944                                                         if (peekChar () == '/') {
1945                                                                 getChar ();
1946                                                                 continue;
1947                                                         }
1948                                                         if (doc_state == XmlCommentState.Allowed)
1949                                                                 docAppend = true;
1950                                                         else if (doc_state == XmlCommentState.NotAllowed)
1951                                                                 warn_incorrect_doc_comment ();
1952                                                 }
1953
1954                                                 int current_comment_start = 0;
1955                                                 if (docAppend) {
1956                                                         current_comment_start = xml_comment_buffer.Length;
1957                                                         xml_comment_buffer.Append (Environment.NewLine);
1958                                                 }
1959
1960                                                 while ((d = getChar ()) != -1){
1961                                                         if (d == '*' && peekChar () == '/'){
1962                                                                 getChar ();
1963                                                                 col++;
1964                                                                 comments_seen = true;
1965                                                                 break;
1966                                                         }
1967                                                         if (docAppend)
1968                                                                 xml_comment_buffer.Append ((char) d);
1969
1970                                                         if (d == '\n'){
1971                                                                 line++;
1972                                                                 ref_line++;
1973                                                                 col = 0;
1974                                                                 any_token_seen |= tokens_seen;
1975                                                                 tokens_seen = false;
1976                                                                 //
1977                                                                 // Reset 'comments_seen' just to be consistent.
1978                                                                 // It doesn't matter either way, here.
1979                                                                 //
1980                                                                 comments_seen = false;
1981                                                         }
1982                                                 }
1983                                                 if (docAppend)
1984                                                         update_formatted_doc_comment (current_comment_start);
1985                                                 continue;
1986                                         }
1987                                         goto is_punct_label;
1988                                 }
1989
1990
1991                                 if (is_identifier_start_character ((char)c)){
1992                                         tokens_seen = true;
1993                                         return consume_identifier (c);
1994                                 }
1995
1996                         is_punct_label:
1997                                 if ((t = is_punct ((char)c, ref doread)) != Token.ERROR){
1998                                         tokens_seen = true;
1999                                         if (doread){
2000                                                 getChar ();
2001                                                 col++;
2002                                         }
2003                                         return t;
2004                                 }
2005
2006                                 // white space
2007                                 if (c == '\n'){
2008                                         line++;
2009                                         ref_line++;
2010                                         col = 0;
2011                                         any_token_seen |= tokens_seen;
2012                                         tokens_seen = false;
2013                                         comments_seen = false;
2014                                         continue;
2015                                 }
2016
2017                                 if (c >= '0' && c <= '9'){
2018                                         tokens_seen = true;
2019                                         return is_number (c);
2020                                 }
2021
2022                                 if (c == '.'){
2023                                         tokens_seen = true;
2024                                         int peek = peekChar ();
2025                                         if (peek >= '0' && peek <= '9')
2026                                                 return is_number (c);
2027                                         return Token.DOT;
2028                                 }
2029
2030                                 /* For now, ignore pre-processor commands */
2031                                 // FIXME: In C# the '#' is not limited to appear
2032                                 // on the first column.
2033                                 if (c == '#') {
2034                                         bool cont = true;
2035
2036                                         if (tokens_seen || comments_seen) {
2037                                                error_details = "Preprocessor directives must appear as the first non-whitespace " +
2038                                                        "character on a line.";
2039
2040                                                Report.Error (1040, Location, error_details);
2041
2042                                                return Token.ERROR;
2043                                        }
2044
2045                                 start_again:
2046
2047                                         cont = handle_preprocessing_directive (cont);
2048
2049                                         if (cont){
2050                                                 col = 0;
2051                                                 continue;
2052                                         }
2053                                         col = 1;
2054
2055                                         bool skipping = false;
2056                                         for (;(c = getChar ()) != -1; col++){
2057                                                 if (c == '\n'){
2058                                                         col = 0;
2059                                                         line++;
2060                                                         ref_line++;
2061                                                         skipping = false;
2062                                                 } else if (c == ' ' || c == '\t' || c == '\v' || c == '\r' || c == 0xa0)
2063                                                         continue;
2064                                                 else if (c != '#')
2065                                                         skipping = true;
2066                                                 if (c == '#' && !skipping)
2067                                                         goto start_again;
2068                                         }
2069                                         any_token_seen |= tokens_seen;
2070                                         tokens_seen = false;
2071                                         if (c == -1)
2072                                                 Report.Error (1027, Location, "#endif/#endregion expected");
2073                                         continue;
2074                                 }
2075
2076                                 if (c == '"')
2077                                         return consume_string (false);
2078
2079                                 if (c == '\''){
2080                                         c = getChar ();
2081                                         tokens_seen = true;
2082                                         if (c == '\''){
2083                                                 error_details = "Empty character literal";
2084                                                 Report.Error (1011, Location, error_details);
2085                                                 return Token.ERROR;
2086                                         }
2087                                         c = escape (c);
2088                                         if (c == -1)
2089                                                 return Token.ERROR;
2090                                         val = new System.Char ();
2091                                         val = (char) c;
2092                                         c = getChar ();
2093
2094                                         if (c != '\''){
2095                                                 error_details = "Too many characters in character literal";
2096                                                 Report.Error (1012, Location, error_details);
2097
2098                                                 // Try to recover, read until newline or next "'"
2099                                                 while ((c = getChar ()) != -1){
2100                                                         if (c == '\n' || c == '\''){
2101                                                                 line++;
2102                                                                 ref_line++;
2103                                                                 col = 0;
2104                                                                 break;
2105                                                         } else
2106                                                                 col++;
2107
2108                                                 }
2109                                                 return Token.ERROR;
2110                                         }
2111                                         return Token.LITERAL_CHARACTER;
2112                                 }
2113
2114                                 if (c == '@') {
2115                                         c = getChar ();
2116                                         if (c == '"') {
2117                                                 tokens_seen = true;
2118                                                 return consume_string (true);
2119                                         } else if (is_identifier_start_character ((char) c)){
2120                                                 return consume_identifier (c, true);
2121                                         } else {
2122                                                 Report.Error (1033, Location, "'@' must be followed by string constant or identifier");
2123                                         }
2124                                 }
2125
2126                                 error_details = ((char)c).ToString ();
2127
2128                                 return Token.ERROR;
2129                         }
2130
2131                         return Token.EOF;
2132                 }
2133
2134                 //
2135                 // Handles one line xml comment
2136                 //
2137                 private void handle_one_line_xml_comment ()
2138                 {
2139                         int c;
2140                         while ((c = peekChar ()) == ' ')
2141                                 getChar (); // skip heading whitespaces.
2142                         while ((c = peekChar ()) != -1 && c != '\n' && c != '\r') {
2143                                 col++;
2144                                 xml_comment_buffer.Append ((char) getChar ());
2145                         }
2146                         if (c == '\r' || c == '\n')
2147                                 xml_comment_buffer.Append (Environment.NewLine);
2148                 }
2149
2150                 //
2151                 // Remove heading "*" in Javadoc-like xml documentation.
2152                 //
2153                 private void update_formatted_doc_comment (int current_comment_start)
2154                 {
2155                         int length = xml_comment_buffer.Length - current_comment_start;
2156                         string [] lines = xml_comment_buffer.ToString (
2157                                 current_comment_start,
2158                                 length).Replace ("\r", "").Split ('\n');
2159
2160                         // The first line starts with /**, thus it is not target
2161                         // for the format check.
2162                         for (int i = 1; i < lines.Length; i++) {
2163                                 string s = lines [i];
2164                                 int idx = s.IndexOf ('*');
2165                                 string head = null;
2166                                 if (idx < 0) {
2167                                         if (i < lines.Length - 1)
2168                                                 return;
2169                                         head = s;
2170                                 } else
2171                                         head = s.Substring (0, idx);
2172                                 foreach (char c in head)
2173                                         if (c != ' ')
2174                                                 return;
2175                                 lines [i] = s.Substring (idx + 1);
2176                         }
2177                         xml_comment_buffer.Remove (current_comment_start, length);
2178                         xml_comment_buffer.Insert (current_comment_start, String.Join (Environment.NewLine, lines));
2179                 }
2180
2181                 //
2182                 // Checks if there was incorrect doc comments and raise
2183                 // warnings.
2184                 //
2185                 public void check_incorrect_doc_comment ()
2186                 {
2187                         if (xml_comment_buffer.Length > 0)
2188                                 warn_incorrect_doc_comment ();
2189                 }
2190
2191                 //
2192                 // Raises a warning when tokenizer found incorrect doccomment
2193                 // markup.
2194                 //
2195                 private void warn_incorrect_doc_comment ()
2196                 {
2197                         doc_state = XmlCommentState.Error;
2198                         // in csc, it is 'XML comment is not placed on a valid
2199                         // language element'. But that does not make sense.
2200                         Report.Warning (1587, 2, Location, "XML comment is placed on an invalid language element which can not accept it.");
2201                 }
2202
2203                 //
2204                 // Consumes the saved xml comment lines (if any)
2205                 // as for current target member or type.
2206                 //
2207                 public string consume_doc_comment ()
2208                 {
2209                         if (xml_comment_buffer.Length > 0) {
2210                                 string ret = xml_comment_buffer.ToString ();
2211                                 xml_comment_buffer.Length = 0;
2212                                 return ret;
2213                         }
2214                         return null;
2215                 }
2216
2217                 public void cleanup ()
2218                 {
2219                         if (ifstack != null && ifstack.Count >= 1) {
2220                                 int state = (int) ifstack.Pop ();
2221                                 if ((state & REGION) != 0)
2222                                         Report.Error (1038, Location, "#endregion directive expected");
2223                                 else
2224                                         Report.Error (1027, "#endif directive expected");
2225                         }
2226
2227                 }
2228         }
2229
2230         //
2231         // Indicates whether it accepts XML documentation or not.
2232         //
2233         public enum XmlCommentState {
2234                 // comment is allowed in this state.
2235                 Allowed,
2236                 // comment is not allowed in this state.
2237                 NotAllowed,
2238                 // once comments appeared when it is NotAllowed, then the
2239                 // state is changed to it, until the state is changed to
2240                 // .Allowed.
2241                 Error
2242         }
2243 }