mcs/mcs/decl.cs

   1 //
   2 // decl.cs: Declaration base class for structs, classes, enums and interfaces.
   3 //
   4 // Author: Miguel de Icaza (miguel@gnu.org)
   5 //
   6 // Licensed under the terms of the GNU GPL
   7 //
   8 // (C) 2001 Ximian, Inc (http://www.ximian.com)
   9 //
  10 // TODO: Move the method verification stuff from the class.cs and interface.cs here
  11 //
  12
  13 using System;
  14 using System.Collections;
  15 using System.Reflection.Emit;
  16 using System.Reflection;
  17
  18 namespace Mono.CSharp {
  19
  20         /// <summary>
  21         ///   Base representation for members.  This is only used to keep track
  22         ///   of Name, Location and Modifier flags.
  23         /// </summary>
  24         public abstract class MemberCore {
  25                 /// <summary>
  26                 ///   Public name
  27                 /// </summary>
  28                 public string Name;
  29
  30                 /// <summary>
  31                 ///   Modifier flags that the user specified in the source code
  32                 /// </summary>
  33                 public int ModFlags;
  34
  35                 /// <summary>
  36                 ///   Location where this declaration happens
  37                 /// </summary>
  38                 public readonly Location Location;
  39
  40                 public MemberCore (string name, Location loc)
  41                 {
  42                         Name = name;
  43                         Location = loc;
  44                 }
  45
  46                 public abstract bool Define (TypeContainer parent);
  47
  48                 //
  49                 // Whehter is it ok to use an unsafe pointer in this type container
  50                 //
  51                 public bool UnsafeOK (DeclSpace parent)
  52                 {
  53                         //
  54                         // First check if this MemberCore modifier flags has unsafe set
  55                         //
  56                         if ((ModFlags & Modifiers.UNSAFE) != 0)
  57                                 return true;
  58
  59                         if (parent.UnsafeContext)
  60                                 return true;
  61
  62                         Expression.UnsafeError (Location);
  63                         return false;
  64                 }
  65         }
  66
  67         /// <summary>
  68         ///   Base class for structs, classes, enumerations and interfaces.
  69         /// </summary>
  70         /// <remarks>
  71         ///   They all create new declaration spaces.  This
  72         ///   provides the common foundation for managing those name
  73         ///   spaces.
  74         /// </remarks>
  75         public abstract class DeclSpace : MemberCore {
  76                 /// <summary>
  77                 ///   this points to the actual definition that is being
  78                 ///   created with System.Reflection.Emit
  79                 /// </summary>
  80                 public TypeBuilder TypeBuilder;
  81
  82                 /// <summary>
  83                 ///   This variable tracks whether we have Closed the type
  84                 /// </summary>
  85                 public bool Created = false;
  86
  87                 //
  88                 // This is the namespace in which this typecontainer
  89                 // was declared.  We use this to resolve names.
  90                 //
  91                 public NamespaceEntry NamespaceEntry;
  92
  93                 public Hashtable Cache = new Hashtable ();
  94
  95                 public string Basename;
  96
  97                 /// <summary>
  98                 ///   defined_names is used for toplevel objects
  99                 /// </summary>
 100                 protected Hashtable defined_names;
 101
 102                 TypeContainer parent;
 103
 104                 public DeclSpace (NamespaceEntry ns, TypeContainer parent, string name, Location l)
 105                         : base (name, l)
 106                 {
 107                         NamespaceEntry = ns;
 108                         Basename = name.Substring (1 + name.LastIndexOf ('.'));
 109                         defined_names = new Hashtable ();
 110                         this.parent = parent;
 111                 }
 112
 113                 public void RecordDecl ()
 114                 {
 115                         if ((NamespaceEntry != null) && (parent == RootContext.Tree.Types))
 116                                 NamespaceEntry.DefineName (Basename, this);
 117                 }
 118
 119                 /// <summary>
 120                 ///   The result value from adding an declaration into
 121                 ///   a struct or a class
 122                 /// </summary>
 123                 public enum AdditionResult {
 124                         /// <summary>
 125                         /// The declaration has been successfully
 126                         /// added to the declation space.
 127                         /// </summary>
 128                         Success,
 129
 130                         /// <summary>
 131                         ///   The symbol has already been defined.
 132                         /// </summary>
 133                         NameExists,
 134
 135                         /// <summary>
 136                         ///   Returned if the declation being added to the
 137                         ///   name space clashes with its container name.
 138                         ///
 139                         ///   The only exceptions for this are constructors
 140                         ///   and static constructors
 141                         /// </summary>
 142                         EnclosingClash,
 143
 144                         /// <summary>
 145                         ///   Returned if a constructor was created (because syntactically
 146                         ///   it looked like a constructor) but was not (because the name
 147                         ///   of the method is not the same as the container class
 148                         /// </summary>
 149                         NotAConstructor,
 150
 151                         /// <summary>
 152                         ///   This is only used by static constructors to emit the
 153                         ///   error 111, but this error for other things really
 154                         ///   happens at another level for other functions.
 155                         /// </summary>
 156                         MethodExists,
 157
 158                         /// <summary>
 159                         ///   Some other error.
 160                         /// </summary>
 161                         Error
 162                 }
 163
 164                 /// <summary>
 165                 ///   Returns a status code based purely on the name
 166                 ///   of the member being added
 167                 /// </summary>
 168                 protected AdditionResult IsValid (string basename, string name)
 169                 {
 170                         if (basename == Basename)
 171                                 return AdditionResult.EnclosingClash;
 172
 173                         if (defined_names.Contains (name))
 174                                 return AdditionResult.NameExists;
 175
 176                         return AdditionResult.Success;
 177                 }
 178
 179                 public static int length;
 180                 public static int small;
 181
 182                 /// <summary>
 183                 ///   Introduce @name into this declaration space and
 184                 ///   associates it with the object @o.  Note that for
 185                 ///   methods this will just point to the first method. o
 186                 /// </summary>
 187                 protected void DefineName (string name, object o)
 188                 {
 189                         defined_names.Add (name, o);
 190
 191 #if DEBUGME
 192                         int p = name.LastIndexOf ('.');
 193                         int l = name.Length;
 194                         length += l;
 195                         small += l -p;
 196 #endif
 197                 }
 198
 199                 /// <summary>
 200                 ///   Returns the object associated with a given name in the declaration
 201                 ///   space.  This is the inverse operation of `DefineName'
 202                 /// </summary>
 203                 public object GetDefinition (string name)
 204                 {
 205                         return defined_names [name];
 206                 }
 207
 208                 bool in_transit = false;
 209
 210                 /// <summary>
 211                 ///   This function is used to catch recursive definitions
 212                 ///   in declarations.
 213                 /// </summary>
 214                 public bool InTransit {
 215                         get {
 216                                 return in_transit;
 217                         }
 218
 219                         set {
 220                                 in_transit = value;
 221                         }
 222                 }
 223
 224                 public TypeContainer Parent {
 225                         get {
 226                                 return parent;
 227                         }
 228                 }
 229
 230                 /// <summary>
 231                 ///   Looks up the alias for the name
 232                 /// </summary>
 233                 public string LookupAlias (string name)
 234                 {
 235                         if (NamespaceEntry != null)
 236                                 return NamespaceEntry.LookupAlias (name);
 237                         else
 238                                 return null;
 239                 }
 240
 241                 //
 242                 // root_types contains all the types.  All TopLevel types
 243                 // hence have a parent that points to `root_types', that is
 244                 // why there is a non-obvious test down here.
 245                 //
 246                 public bool IsTopLevel {
 247                         get {
 248                                 if (parent != null){
 249                                         if (parent.parent == null)
 250                                                 return true;
 251                                 }
 252                                 return false;
 253                         }
 254                 }
 255
 256                 public virtual void CloseType ()
 257                 {
 258                         if (!Created){
 259                                 try {
 260                                         TypeBuilder.CreateType ();
 261                                 } catch {
 262                                         //
 263                                         // The try/catch is needed because
 264                                         // nested enumerations fail to load when they
 265                                         // are defined.
 266                                         //
 267                                         // Even if this is the right order (enumerations
 268                                         // declared after types).
 269                                         //
 270                                         // Note that this still creates the type and
 271                                         // it is possible to save it
 272                                 }
 273                                 Created = true;
 274                         }
 275                 }
 276
 277                 /// <remarks>
 278                 ///  Should be overriten by the appropriate declaration space
 279                 /// </remarks>
 280                 public abstract TypeBuilder DefineType ();
 281
 282                 /// <summary>
 283                 ///   Define all members, but don't apply any attributes or do anything which may
 284                 ///   access not-yet-defined classes.  This method also creates the MemberCache.
 285                 /// </summary>
 286                 public abstract bool DefineMembers (TypeContainer parent);
 287
 288                 //
 289                 // Whether this is an `unsafe context'
 290                 //
 291                 public bool UnsafeContext {
 292                         get {
 293                                 if ((ModFlags & Modifiers.UNSAFE) != 0)
 294                                         return true;
 295                                 if (parent != null)
 296                                         return parent.UnsafeContext;
 297                                 return false;
 298                         }
 299                 }
 300
 301                 public static string MakeFQN (string nsn, string name)
 302                 {
 303                         if (nsn == "")
 304                                 return name;
 305                         return String.Concat (nsn, ".", name);
 306                 }
 307
 308                 EmitContext type_resolve_ec;
 309                 EmitContext GetTypeResolveEmitContext (TypeContainer parent, Location loc)
 310                 {
 311                         type_resolve_ec = new EmitContext (parent, this, loc, null, null, ModFlags, false);
 312                         type_resolve_ec.ResolvingTypeTree = true;
 313
 314                         return type_resolve_ec;
 315                 }
 316
 317                 // <summary>
 318                 //    Looks up the type, as parsed into the expression `e'
 319                 // </summary>
 320                 public Type ResolveType (Expression e, bool silent, Location loc)
 321                 {
 322                         if (type_resolve_ec == null)
 323                                 type_resolve_ec = GetTypeResolveEmitContext (parent, loc);
 324                         type_resolve_ec.loc = loc;
 325                         type_resolve_ec.ContainerType = TypeBuilder;
 326
 327                         int errors = Report.Errors;
 328                         TypeExpr d = e.ResolveAsTypeTerminal (type_resolve_ec);
 329
 330                         if (d == null || d.eclass != ExprClass.Type){
 331                                 if (!silent && errors == Report.Errors){
 332                                         Report.Error (246, loc, "Cannot find type `"+ e.ToString () +"'");
 333                                 }
 334                                 return null;
 335                         }
 336
 337                         if (!d.CheckAccessLevel (this)) {
 338                                 Report. Error (122, loc,  "`" + d.Name + "' " +
 339                                        "is inaccessible because of its protection level");
 340                                 return null;
 341                         }
 342
 343                         return d.Type;
 344                 }
 345
 346                 // <summary>
 347                 //    Resolves the expression `e' for a type, and will recursively define
 348                 //    types.
 349                 // </summary>
 350                 public TypeExpr ResolveTypeExpr (Expression e, bool silent, Location loc)
 351                 {
 352                         if (type_resolve_ec == null)
 353                                 type_resolve_ec = GetTypeResolveEmitContext (parent, loc);
 354                         type_resolve_ec.loc = loc;
 355                         type_resolve_ec.ContainerType = TypeBuilder;
 356
 357                         TypeExpr d = e.ResolveAsTypeTerminal (type_resolve_ec);
 358
 359                         if (d == null || d.eclass != ExprClass.Type){
 360                                 if (!silent){
 361                                         Report.Error (246, loc, "Cannot find type `"+ e +"'");
 362                                 }
 363                                 return null;
 364                         }
 365
 366                         return d;
 367                 }
 368
 369                 public bool CheckAccessLevel (Type check_type)
 370                 {
 371                         if (check_type == TypeBuilder)
 372                                 return true;
 373
 374                         TypeAttributes check_attr = check_type.Attributes & TypeAttributes.VisibilityMask;
 375
 376                         //
 377                         // Broken Microsoft runtime, return public for arrays, no matter what
 378                         // the accessibility is for their underlying class, and they return
 379                         // NonPublic visibility for pointers
 380                         //
 381                         if (check_type.IsArray || check_type.IsPointer)
 382                                 return CheckAccessLevel (TypeManager.GetElementType (check_type));
 383
 384                         switch (check_attr){
 385                         case TypeAttributes.Public:
 386                                 return true;
 387
 388                         case TypeAttributes.NotPublic:
 389                                 //
 390                                 // This test should probably use the declaringtype.
 391                                 //
 392                                 if (check_type.Assembly == TypeBuilder.Assembly){
 393                                         return true;
 394                                 }
 395                                 return false;
 396
 397                         case TypeAttributes.NestedPublic:
 398                                 return true;
 399
 400                         case TypeAttributes.NestedPrivate:
 401                                 string check_type_name = check_type.FullName;
 402                                 string type_name = TypeBuilder.FullName;
 403
 404                                 int cio = check_type_name.LastIndexOf ('+');
 405                                 string container = check_type_name.Substring (0, cio);
 406
 407                                 //
 408                                 // Check if the check_type is a nested class of the current type
 409                                 //
 410                                 if (check_type_name.StartsWith (type_name + "+")){
 411                                         return true;
 412                                 }
 413
 414                                 if (type_name.StartsWith (container)){
 415                                         return true;
 416                                 }
 417
 418                                 return false;
 419
 420                         case TypeAttributes.NestedFamily:
 421                                 //
 422                                 // Only accessible to methods in current type or any subtypes
 423                                 //
 424                                 return FamilyAccessible (check_type);
 425
 426                         case TypeAttributes.NestedFamANDAssem:
 427                                 return (check_type.Assembly == TypeBuilder.Assembly) &&
 428                                         FamilyAccessible (check_type);
 429
 430                         case TypeAttributes.NestedFamORAssem:
 431                                 return (check_type.Assembly == TypeBuilder.Assembly) ||
 432                                         FamilyAccessible (check_type);
 433
 434                         case TypeAttributes.NestedAssembly:
 435                                 return check_type.Assembly == TypeBuilder.Assembly;
 436                         }
 437
 438                         Console.WriteLine ("HERE: " + check_attr);
 439                         return false;
 440
 441                 }
 442
 443                 protected bool FamilyAccessible (Type check_type)
 444                 {
 445                         Type declaring = check_type.DeclaringType;
 446                         if (TypeBuilder.IsSubclassOf (declaring))
 447                                 return true;
 448
 449                         string check_type_name = check_type.FullName;
 450                         string type_name = TypeBuilder.FullName;
 451
 452                         int cio = check_type_name.LastIndexOf ('+');
 453                         string container = check_type_name.Substring (0, cio);
 454
 455                         //
 456                         // Check if the check_type is a nested class of the current type
 457                         //
 458                         if (check_type_name.StartsWith (container + "+"))
 459                                 return true;
 460
 461                         return false;
 462                 }
 463
 464                 // Access level of a type.
 465                 enum AccessLevel {
 466                         Public                  = 0,
 467                         ProtectedInternal       = 1,
 468                         Internal                = 2,
 469                         Protected               = 3,
 470                         Private                 = 4
 471                 }
 472
 473                 // Check whether `flags' denotes a more restricted access than `level'
 474                 // and return the new level.
 475                 static AccessLevel CheckAccessLevel (AccessLevel level, int flags)
 476                 {
 477                         AccessLevel old_level = level;
 478
 479                         if ((flags & Modifiers.INTERNAL) != 0) {
 480                                 if ((flags & Modifiers.PROTECTED) != 0) {
 481                                         if ((int) level < (int) AccessLevel.ProtectedInternal)
 482                                                 level = AccessLevel.ProtectedInternal;
 483                                 } else {
 484                                         if ((int) level < (int) AccessLevel.Internal)
 485                                                 level = AccessLevel.Internal;
 486                                 }
 487                         } else if ((flags & Modifiers.PROTECTED) != 0) {
 488                                 if ((int) level < (int) AccessLevel.Protected)
 489                                         level = AccessLevel.Protected;
 490                         } else if ((flags & Modifiers.PRIVATE) != 0)
 491                                 level = AccessLevel.Private;
 492
 493                         return level;
 494                 }
 495
 496                 // Return the access level for a new member which is defined in the current
 497                 // TypeContainer with access modifiers `flags'.
 498                 AccessLevel GetAccessLevel (int flags)
 499                 {
 500                         if ((flags & Modifiers.PRIVATE) != 0)
 501                                 return AccessLevel.Private;
 502
 503                         AccessLevel level;
 504                         if (!IsTopLevel && (Parent != null))
 505                                 level = Parent.GetAccessLevel (flags);
 506                         else
 507                                 level = AccessLevel.Public;
 508
 509                         return CheckAccessLevel (CheckAccessLevel (level, flags), ModFlags);
 510                 }
 511
 512                 // Return the access level for type `t', but don't give more access than `flags'.
 513                 static AccessLevel GetAccessLevel (Type t, int flags)
 514                 {
 515                         if (((flags & Modifiers.PRIVATE) != 0) || t.IsNestedPrivate)
 516                                 return AccessLevel.Private;
 517
 518                         AccessLevel level;
 519                         if (TypeManager.IsBuiltinType (t))
 520                                 return AccessLevel.Public;
 521                         else if ((t.DeclaringType != null) && (t != t.DeclaringType))
 522                                 level = GetAccessLevel (t.DeclaringType, flags);
 523                         else {
 524                                 level = CheckAccessLevel (AccessLevel.Public, flags);
 525                         }
 526
 527                         if (t.IsNestedPublic)
 528                                 return level;
 529
 530                         if (t.IsNestedAssembly || t.IsNotPublic) {
 531                                 if ((int) level < (int) AccessLevel.Internal)
 532                                         level = AccessLevel.Internal;
 533                         }
 534
 535                         if (t.IsNestedFamily) {
 536                                 if ((int) level < (int) AccessLevel.Protected)
 537                                         level = AccessLevel.Protected;
 538                         }
 539
 540                         if (t.IsNestedFamORAssem) {
 541                                 if ((int) level < (int) AccessLevel.ProtectedInternal)
 542                                         level = AccessLevel.ProtectedInternal;
 543                         }
 544
 545                         return level;
 546                 }
 547
 548                 //
 549                 // Returns true if `parent' is as accessible as the flags `flags'
 550                 // given for this member.
 551                 //
 552                 public bool AsAccessible (Type parent, int flags)
 553                 {
 554                         while (parent.IsArray || parent.IsPointer || parent.IsByRef)
 555                                 parent = TypeManager.GetElementType (parent);
 556
 557                         AccessLevel level = GetAccessLevel (flags);
 558                         AccessLevel level2 = GetAccessLevel (parent, flags);
 559
 560                         return (int) level >= (int) level2;
 561                 }
 562
 563                 static DoubleHash dh = new DoubleHash (1000);
 564
 565                 Type LookupInterfaceOrClass (string ns, string name, out bool error)
 566                 {
 567                         DeclSpace parent;
 568                         Type t;
 569                         object r;
 570
 571                         error = false;
 572
 573                         if (dh.Lookup (ns, name, out r))
 574                                 return (Type) r;
 575                         else {
 576                                 if (ns != ""){
 577                                         if (Namespace.IsNamespace (ns)){
 578                                                 string fullname = (ns != "") ? ns + "." + name : name;
 579                                                 t = TypeManager.LookupType (fullname);
 580                                         } else
 581                                                 t = null;
 582                                 } else
 583                                         t = TypeManager.LookupType (name);
 584                         }
 585
 586                         if (t != null) {
 587                                 dh.Insert (ns, name, t);
 588                                 return t;
 589                         }
 590
 591                         //
 592                         // In case we are fed a composite name, normalize it.
 593                         //
 594                         int p = name.LastIndexOf ('.');
 595                         if (p != -1){
 596                                 ns = MakeFQN (ns, name.Substring (0, p));
 597                                 name = name.Substring (p+1);
 598                         }
 599
 600                         parent = RootContext.Tree.LookupByNamespace (ns, name);
 601                         if (parent == null) {
 602                                 dh.Insert (ns, name, null);
 603                                 return null;
 604                         }
 605
 606                         t = parent.DefineType ();
 607                         if (t == null){
 608                                 error = true;
 609                                 return null;
 610                         }
 611
 612                         dh.Insert (ns, name, t);
 613                         return t;
 614                 }
 615
 616                 public static void Error_AmbiguousTypeReference (Location loc, string name, Type t1, Type t2)
 617                 {
 618                         Report.Error (104, loc,
 619                                       String.Format ("`{0}' is an ambiguous reference ({1} or {2}) ", name,
 620                                                      t1.FullName, t2.FullName));
 621                 }
 622
 623                 /// <summary>
 624                 ///   GetType is used to resolve type names at the DeclSpace level.
 625                 ///   Use this to lookup class/struct bases, interface bases or
 626                 ///   delegate type references
 627                 /// </summary>
 628                 ///
 629                 /// <remarks>
 630                 ///   Contrast this to LookupType which is used inside method bodies to
 631                 ///   lookup types that have already been defined.  GetType is used
 632                 ///   during the tree resolution process and potentially define
 633                 ///   recursively the type
 634                 /// </remarks>
 635                 public Type FindType (Location loc, string name)
 636                 {
 637                         Type t;
 638                         bool error;
 639
 640                         //
 641                         // For the case the type we are looking for is nested within this one
 642                         // or is in any base class
 643                         //
 644                         DeclSpace containing_ds = this;
 645
 646                         while (containing_ds != null){
 647                                 Type container_type = containing_ds.TypeBuilder;
 648                                 Type current_type = container_type;
 649
 650                                 while (current_type != null && current_type != TypeManager.object_type) {
 651                                         string pre = current_type.FullName;
 652
 653                                         t = LookupInterfaceOrClass (pre, name, out error);
 654                                         if (error)
 655                                                 return null;
 656
 657                                         if ((t != null) && containing_ds.CheckAccessLevel (t))
 658                                                 return t;
 659
 660                                         current_type = current_type.BaseType;
 661                                 }
 662                                 containing_ds = containing_ds.Parent;
 663                         }
 664
 665                         //
 666                         // Attempt to lookup the class on our namespace and all it's implicit parents
 667                         //
 668                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.ImplicitParent) {
 669                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 670                                 if (error)
 671                                         return null;
 672
 673                                 if (t != null)
 674                                         return t;
 675                         }
 676
 677                         //
 678                         // Attempt to do a direct unqualified lookup
 679                         //
 680                         t = LookupInterfaceOrClass ("", name, out error);
 681                         if (error)
 682                                 return null;
 683
 684                         if (t != null)
 685                                 return t;
 686
 687                         //
 688                         // Attempt to lookup the class on any of the `using'
 689                         // namespaces
 690                         //
 691
 692                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.Parent){
 693
 694                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 695                                 if (error)
 696                                         return null;
 697
 698                                 if (t != null)
 699                                         return t;
 700
 701                                 //
 702                                 // Now check the using clause list
 703                                 //
 704                                 Type match = null;
 705                                 foreach (Namespace using_ns in ns.GetUsingTable ()) {
 706                                         match = LookupInterfaceOrClass (using_ns.Name, name, out error);
 707                                         if (error)
 708                                                 return null;
 709
 710                                         if (match != null){
 711                                                 if (t != null){
 712                                                         if (CheckAccessLevel (match)) {
 713                                                                 Error_AmbiguousTypeReference (loc, name, t, match);
 714                                                                 return null;
 715                                                         }
 716                                                         continue;
 717                                                 }
 718
 719                                                 t = match;
 720                                         }
 721                                 }
 722                                 if (t != null)
 723                                         return t;
 724                         }
 725
 726                         //Report.Error (246, Location, "Can not find type `"+name+"'");
 727                         return null;
 728                 }
 729
 730                 /// <remarks>
 731                 ///   This function is broken and not what you're looking for.  It should only
 732                 ///   be used while the type is still being created since it doesn't use the cache
 733                 ///   and relies on the filter doing the member name check.
 734                 /// </remarks>
 735                 public abstract MemberList FindMembers (MemberTypes mt, BindingFlags bf,
 736                                                         MemberFilter filter, object criteria);
 737
 738                 /// <remarks>
 739                 ///   If we have a MemberCache, return it.  This property may return null if the
 740                 ///   class doesn't have a member cache or while it's still being created.
 741                 /// </remarks>
 742                 public abstract MemberCache MemberCache {
 743                         get;
 744                 }
 745         }
 746
 747         /// <summary>
 748         ///   This is a readonly list of MemberInfo's.
 749         /// </summary>
 750         public class MemberList : IList {
 751                 public readonly IList List;
 752                 int count;
 753
 754                 /// <summary>
 755                 ///   Create a new MemberList from the given IList.
 756                 /// </summary>
 757                 public MemberList (IList list)
 758                 {
 759                         if (list != null)
 760                                 this.List = list;
 761                         else
 762                                 this.List = new ArrayList ();
 763                         count = List.Count;
 764                 }
 765
 766                 /// <summary>
 767                 ///   Concatenate the ILists `first' and `second' to a new MemberList.
 768                 /// </summary>
 769                 public MemberList (IList first, IList second)
 770                 {
 771                         ArrayList list = new ArrayList ();
 772                         list.AddRange (first);
 773                         list.AddRange (second);
 774                         count = list.Count;
 775                         List = list;
 776                 }
 777
 778                 public static readonly MemberList Empty = new MemberList (new ArrayList ());
 779
 780                 /// <summary>
 781                 ///   Cast the MemberList into a MemberInfo[] array.
 782                 /// </summary>
 783                 /// <remarks>
 784                 ///   This is an expensive operation, only use it if it's really necessary.
 785                 /// </remarks>
 786                 public static explicit operator MemberInfo [] (MemberList list)
 787                 {
 788                         Timer.StartTimer (TimerType.MiscTimer);
 789                         MemberInfo [] result = new MemberInfo [list.Count];
 790                         list.CopyTo (result, 0);
 791                         Timer.StopTimer (TimerType.MiscTimer);
 792                         return result;
 793                 }
 794
 795                 // ICollection
 796
 797                 public int Count {
 798                         get {
 799                                 return count;
 800                         }
 801                 }
 802
 803                 public bool IsSynchronized {
 804                         get {
 805                                 return List.IsSynchronized;
 806                         }
 807                 }
 808
 809                 public object SyncRoot {
 810                         get {
 811                                 return List.SyncRoot;
 812                         }
 813                 }
 814
 815                 public void CopyTo (Array array, int index)
 816                 {
 817                         List.CopyTo (array, index);
 818                 }
 819
 820                 // IEnumerable
 821
 822                 public IEnumerator GetEnumerator ()
 823                 {
 824                         return List.GetEnumerator ();
 825                 }
 826
 827                 // IList
 828
 829                 public bool IsFixedSize {
 830                         get {
 831                                 return true;
 832                         }
 833                 }
 834
 835                 public bool IsReadOnly {
 836                         get {
 837                                 return true;
 838                         }
 839                 }
 840
 841                 object IList.this [int index] {
 842                         get {
 843                                 return List [index];
 844                         }
 845
 846                         set {
 847                                 throw new NotSupportedException ();
 848                         }
 849                 }
 850
 851                 // FIXME: try to find out whether we can avoid the cast in this indexer.
 852                 public MemberInfo this [int index] {
 853                         get {
 854                                 return (MemberInfo) List [index];
 855                         }
 856                 }
 857
 858                 public int Add (object value)
 859                 {
 860                         throw new NotSupportedException ();
 861                 }
 862
 863                 public void Clear ()
 864                 {
 865                         throw new NotSupportedException ();
 866                 }
 867
 868                 public bool Contains (object value)
 869                 {
 870                         return List.Contains (value);
 871                 }
 872
 873                 public int IndexOf (object value)
 874                 {
 875                         return List.IndexOf (value);
 876                 }
 877
 878                 public void Insert (int index, object value)
 879                 {
 880                         throw new NotSupportedException ();
 881                 }
 882
 883                 public void Remove (object value)
 884                 {
 885                         throw new NotSupportedException ();
 886                 }
 887
 888                 public void RemoveAt (int index)
 889                 {
 890                         throw new NotSupportedException ();
 891                 }
 892         }
 893
 894         /// <summary>
 895         ///   This interface is used to get all members of a class when creating the
 896         ///   member cache.  It must be implemented by all DeclSpace derivatives which
 897         ///   want to support the member cache and by TypeHandle to get caching of
 898         ///   non-dynamic types.
 899         /// </summary>
 900         public interface IMemberContainer {
 901                 /// <summary>
 902                 ///   The name of the IMemberContainer.  This is only used for
 903                 ///   debugging purposes.
 904                 /// </summary>
 905                 string Name {
 906                         get;
 907                 }
 908
 909                 /// <summary>
 910                 ///   The type of this IMemberContainer.
 911                 /// </summary>
 912                 Type Type {
 913                         get;
 914                 }
 915
 916                 /// <summary>
 917                 ///   Returns the IMemberContainer of the parent class or null if this
 918                 ///   is an interface or TypeManger.object_type.
 919                 ///   This is used when creating the member cache for a class to get all
 920                 ///   members from the parent class.
 921                 /// </summary>
 922                 IMemberContainer Parent {
 923                         get;
 924                 }
 925
 926                 /// <summary>
 927                 ///   Whether this is an interface.
 928                 /// </summary>
 929                 bool IsInterface {
 930                         get;
 931                 }
 932
 933                 /// <summary>
 934                 ///   Returns all members of this class with the corresponding MemberTypes
 935                 ///   and BindingFlags.
 936                 /// </summary>
 937                 /// <remarks>
 938                 ///   When implementing this method, make sure not to return any inherited
 939                 ///   members and check the MemberTypes and BindingFlags properly.
 940                 ///   Unfortunately, System.Reflection is lame and doesn't provide a way to
 941                 ///   get the BindingFlags (static/non-static,public/non-public) in the
 942                 ///   MemberInfo class, but the cache needs this information.  That's why
 943                 ///   this method is called multiple times with different BindingFlags.
 944                 /// </remarks>
 945                 MemberList GetMembers (MemberTypes mt, BindingFlags bf);
 946
 947                 /// <summary>
 948                 ///   Return the container's member cache.
 949                 /// </summary>
 950                 MemberCache MemberCache {
 951                         get;
 952                 }
 953         }
 954
 955         /// <summary>
 956         ///   The MemberCache is used by dynamic and non-dynamic types to speed up
 957         ///   member lookups.  It has a member name based hash table; it maps each member
 958         ///   name to a list of CacheEntry objects.  Each CacheEntry contains a MemberInfo
 959         ///   and the BindingFlags that were initially used to get it.  The cache contains
 960         ///   all members of the current class and all inherited members.  If this cache is
 961         ///   for an interface types, it also contains all inherited members.
 962         ///
 963         ///   There are two ways to get a MemberCache:
 964         ///   * if this is a dynamic type, lookup the corresponding DeclSpace and then
 965         ///     use the DeclSpace.MemberCache property.
 966         ///   * if this not a dynamic type, call TypeHandle.GetTypeHandle() to get a
 967         ///     TypeHandle instance for the type and then use TypeHandle.MemberCache.
 968         /// </summary>
 969         public class MemberCache {
 970                 public readonly IMemberContainer Container;
 971                 protected Hashtable member_hash;
 972                 protected Hashtable method_hash;
 973                 protected Hashtable interface_hash;
 974
 975                 /// <summary>
 976                 ///   Create a new MemberCache for the given IMemberContainer `container'.
 977                 /// </summary>
 978                 public MemberCache (IMemberContainer container)
 979                 {
 980                         this.Container = container;
 981
 982                         Timer.IncrementCounter (CounterType.MemberCache);
 983                         Timer.StartTimer (TimerType.CacheInit);
 984
 985                         interface_hash = new Hashtable ();
 986
 987                         // If we have a parent class (we have a parent class unless we're
 988                         // TypeManager.object_type), we deep-copy its MemberCache here.
 989                         if (Container.IsInterface) {
 990                                 MemberCache parent;
 991                                 if (Container.Parent != null)
 992                                         parent = Container.Parent.MemberCache;
 993                                 else
 994                                         parent = TypeHandle.ObjectType.MemberCache;
 995                                 member_hash = SetupCacheForInterface (parent);
 996                         } else if (Container.Parent != null)
 997                                 member_hash = SetupCache (Container.Parent.MemberCache);
 998                         else
 999                                 member_hash = new Hashtable ();
1000
1001                         // If this is neither a dynamic type nor an interface, create a special
1002                         // method cache with all declared and inherited methods.
1003                         Type type = container.Type;
1004                         if (!(type is TypeBuilder) && !type.IsInterface) {
1005                                 method_hash = new Hashtable ();
1006                                 AddMethods (type);
1007                         }
1008
1009                         // Add all members from the current class.
1010                         AddMembers (Container);
1011
1012                         Timer.StopTimer (TimerType.CacheInit);
1013                 }
1014
1015                 /// <summary>
1016                 ///   Bootstrap this member cache by doing a deep-copy of our parent.
1017                 /// </summary>
1018                 Hashtable SetupCache (MemberCache parent)
1019                 {
1020                         Hashtable hash = new Hashtable ();
1021
1022                         IDictionaryEnumerator it = parent.member_hash.GetEnumerator ();
1023                         while (it.MoveNext ()) {
1024                                 hash [it.Key] = ((ArrayList) it.Value).Clone ();
1025                         }
1026
1027                         return hash;
1028                 }
1029
1030                 void AddInterfaces (MemberCache parent)
1031                 {
1032                         foreach (Type iface in parent.interface_hash.Keys) {
1033                                 if (!interface_hash.Contains (iface))
1034                                         interface_hash.Add (iface, true);
1035                         }
1036                 }
1037
1038                 /// <summary>
1039                 ///   Add the contents of `new_hash' to `hash'.
1040                 /// </summary>
1041                 void AddHashtable (Hashtable hash, Hashtable new_hash)
1042                 {
1043                         IDictionaryEnumerator it = new_hash.GetEnumerator ();
1044                         while (it.MoveNext ()) {
1045                                 ArrayList list = (ArrayList) hash [it.Key];
1046                                 if (list != null)
1047                                         list.AddRange ((ArrayList) it.Value);
1048                                 else
1049                                         hash [it.Key] = ((ArrayList) it.Value).Clone ();
1050                         }
1051                 }
1052
1053                 /// <summary>
1054                 ///   Bootstrap the member cache for an interface type.
1055                 ///   Type.GetMembers() won't return any inherited members for interface types,
1056                 ///   so we need to do this manually.  Interfaces also inherit from System.Object.
1057                 /// </summary>
1058                 Hashtable SetupCacheForInterface (MemberCache parent)
1059                 {
1060                         Hashtable hash = SetupCache (parent);
1061                         TypeExpr [] ifaces = TypeManager.GetInterfaces (Container.Type);
1062
1063                         foreach (TypeExpr iface in ifaces) {
1064                                 Type itype = iface.Type;
1065
1066                                 if (interface_hash.Contains (itype))
1067                                         continue;
1068                                 interface_hash.Add (itype, true);
1069
1070                                 IMemberContainer iface_container =
1071                                         TypeManager.LookupMemberContainer (itype);
1072
1073                                 MemberCache iface_cache = iface_container.MemberCache;
1074
1075                                 AddHashtable (hash, iface_cache.member_hash);
1076                                 AddInterfaces (iface_cache);
1077                         }
1078
1079                         return hash;
1080                 }
1081
1082                 /// <summary>
1083                 ///   Add all members from class `container' to the cache.
1084                 /// </summary>
1085                 void AddMembers (IMemberContainer container)
1086                 {
1087                         // We need to call AddMembers() with a single member type at a time
1088                         // to get the member type part of CacheEntry.EntryType right.
1089                         AddMembers (MemberTypes.Constructor, container);
1090                         AddMembers (MemberTypes.Field, container);
1091                         AddMembers (MemberTypes.Method, container);
1092                         AddMembers (MemberTypes.Property, container);
1093                         AddMembers (MemberTypes.Event, container);
1094                         // Nested types are returned by both Static and Instance searches.
1095                         AddMembers (MemberTypes.NestedType,
1096                                     BindingFlags.Static | BindingFlags.Public, container);
1097                         AddMembers (MemberTypes.NestedType,
1098                                     BindingFlags.Static | BindingFlags.NonPublic, container);
1099                 }
1100
1101                 void AddMembers (MemberTypes mt, IMemberContainer container)
1102                 {
1103                         AddMembers (mt, BindingFlags.Static | BindingFlags.Public, container);
1104                         AddMembers (mt, BindingFlags.Static | BindingFlags.NonPublic, container);
1105                         AddMembers (mt, BindingFlags.Instance | BindingFlags.Public, container);
1106                         AddMembers (mt, BindingFlags.Instance | BindingFlags.NonPublic, container);
1107                 }
1108
1109                 /// <summary>
1110                 ///   Add all members from class `container' with the requested MemberTypes and
1111                 ///   BindingFlags to the cache.  This method is called multiple times with different
1112                 ///   MemberTypes and BindingFlags.
1113                 /// </summary>
1114                 void AddMembers (MemberTypes mt, BindingFlags bf, IMemberContainer container)
1115                 {
1116                         MemberList members = container.GetMembers (mt, bf);
1117                         BindingFlags new_bf = (container == Container) ?
1118                                 bf | BindingFlags.DeclaredOnly : bf;
1119
1120                         foreach (MemberInfo member in members) {
1121                                 string name = member.Name;
1122
1123                                 // We use a name-based hash table of ArrayList's.
1124                                 ArrayList list = (ArrayList) member_hash [name];
1125                                 if (list == null) {
1126                                         list = new ArrayList ();
1127                                         member_hash.Add (name, list);
1128                                 }
1129
1130                                 // When this method is called for the current class, the list will
1131                                 // already contain all inherited members from our parent classes.
1132                                 // We cannot add new members in front of the list since this'd be an
1133                                 // expensive operation, that's why the list is sorted in reverse order
1134                                 // (ie. members from the current class are coming last).
1135                                 list.Add (new CacheEntry (container, member, mt, bf));
1136                         }
1137                 }
1138
1139                 /// <summary>
1140                 ///   Add all declared and inherited methods from class `type' to the method cache.
1141                 /// </summary>
1142                 void AddMethods (Type type)
1143                 {
1144                         AddMethods (BindingFlags.Static | BindingFlags.Public |
1145                                     BindingFlags.FlattenHierarchy, type);
1146                         AddMethods (BindingFlags.Static | BindingFlags.NonPublic |
1147                                     BindingFlags.FlattenHierarchy, type);
1148                         AddMethods (BindingFlags.Instance | BindingFlags.Public, type);
1149                         AddMethods (BindingFlags.Instance | BindingFlags.NonPublic, type);
1150                 }
1151
1152                 void AddMethods (BindingFlags bf, Type type)
1153                 {
1154                         MemberInfo [] members = type.GetMethods (bf);
1155
1156                         Array.Reverse (members);
1157
1158                         foreach (MethodBase member in members) {
1159                                 string name = member.Name;
1160
1161                                 // Varargs methods aren't allowed in C# code.
1162                                 if ((member.CallingConvention & CallingConventions.VarArgs) != 0)
1163                                         continue;
1164
1165                                 // We use a name-based hash table of ArrayList's.
1166                                 ArrayList list = (ArrayList) method_hash [name];
1167                                 if (list == null) {
1168                                         list = new ArrayList ();
1169                                         method_hash.Add (name, list);
1170                                 }
1171
1172                                 // Unfortunately, the elements returned by Type.GetMethods() aren't
1173                                 // sorted so we need to do this check for every member.
1174                                 BindingFlags new_bf = bf;
1175                                 if (member.DeclaringType == type)
1176                                         new_bf |= BindingFlags.DeclaredOnly;
1177
1178                                 list.Add (new CacheEntry (Container, member, MemberTypes.Method, new_bf));
1179                         }
1180
1181
1182                 }
1183
1184                 /// <summary>
1185                 ///   Compute and return a appropriate `EntryType' magic number for the given
1186                 ///   MemberTypes and BindingFlags.
1187                 /// </summary>
1188                 protected static EntryType GetEntryType (MemberTypes mt, BindingFlags bf)
1189                 {
1190                         EntryType type = EntryType.None;
1191
1192                         if ((mt & MemberTypes.Constructor) != 0)
1193                                 type |= EntryType.Constructor;
1194                         if ((mt & MemberTypes.Event) != 0)
1195                                 type |= EntryType.Event;
1196                         if ((mt & MemberTypes.Field) != 0)
1197                                 type |= EntryType.Field;
1198                         if ((mt & MemberTypes.Method) != 0)
1199                                 type |= EntryType.Method;
1200                         if ((mt & MemberTypes.Property) != 0)
1201                                 type |= EntryType.Property;
1202                         // Nested types are returned by static and instance searches.
1203                         if ((mt & MemberTypes.NestedType) != 0)
1204                                 type |= EntryType.NestedType | EntryType.Static | EntryType.Instance;
1205
1206                         if ((bf & BindingFlags.Instance) != 0)
1207                                 type |= EntryType.Instance;
1208                         if ((bf & BindingFlags.Static) != 0)
1209                                 type |= EntryType.Static;
1210                         if ((bf & BindingFlags.Public) != 0)
1211                                 type |= EntryType.Public;
1212                         if ((bf & BindingFlags.NonPublic) != 0)
1213                                 type |= EntryType.NonPublic;
1214                         if ((bf & BindingFlags.DeclaredOnly) != 0)
1215                                 type |= EntryType.Declared;
1216
1217                         return type;
1218                 }
1219
1220                 /// <summary>
1221                 ///   The `MemberTypes' enumeration type is a [Flags] type which means that it may
1222                 ///   denote multiple member types.  Returns true if the given flags value denotes a
1223                 ///   single member types.
1224                 /// </summary>
1225                 public static bool IsSingleMemberType (MemberTypes mt)
1226                 {
1227                         switch (mt) {
1228                         case MemberTypes.Constructor:
1229                         case MemberTypes.Event:
1230                         case MemberTypes.Field:
1231                         case MemberTypes.Method:
1232                         case MemberTypes.Property:
1233                         case MemberTypes.NestedType:
1234                                 return true;
1235
1236                         default:
1237                                 return false;
1238                         }
1239                 }
1240
1241                 /// <summary>
1242                 ///   We encode the MemberTypes and BindingFlags of each members in a "magic"
1243                 ///   number to speed up the searching process.
1244                 /// </summary>
1245                 [Flags]
1246                 protected enum EntryType {
1247                         None            = 0x000,
1248
1249                         Instance        = 0x001,
1250                         Static          = 0x002,
1251                         MaskStatic      = Instance|Static,
1252
1253                         Public          = 0x004,
1254                         NonPublic       = 0x008,
1255                         MaskProtection  = Public|NonPublic,
1256
1257                         Declared        = 0x010,
1258
1259                         Constructor     = 0x020,
1260                         Event           = 0x040,
1261                         Field           = 0x080,
1262                         Method          = 0x100,
1263                         Property        = 0x200,
1264                         NestedType      = 0x400,
1265
1266                         MaskType        = Constructor|Event|Field|Method|Property|NestedType
1267                 }
1268
1269                 protected struct CacheEntry {
1270                         public readonly IMemberContainer Container;
1271                         public readonly EntryType EntryType;
1272                         public readonly MemberInfo Member;
1273
1274                         public CacheEntry (IMemberContainer container, MemberInfo member,
1275                                            MemberTypes mt, BindingFlags bf)
1276                         {
1277                                 this.Container = container;
1278                                 this.Member = member;
1279                                 this.EntryType = GetEntryType (mt, bf);
1280                         }
1281                 }
1282
1283                 /// <summary>
1284                 ///   This is called each time we're walking up one level in the class hierarchy
1285                 ///   and checks whether we can abort the search since we've already found what
1286                 ///   we were looking for.
1287                 /// </summary>
1288                 protected bool DoneSearching (ArrayList list)
1289                 {
1290                         //
1291                         // We've found exactly one member in the current class and it's not
1292                         // a method or constructor.
1293                         //
1294                         if (list.Count == 1 && !(list [0] is MethodBase))
1295                                 return true;
1296
1297                         //
1298                         // Multiple properties: we query those just to find out the indexer
1299                         // name
1300                         //
1301                         if ((list.Count > 0) && (list [0] is PropertyInfo))
1302                                 return true;
1303
1304                         return false;
1305                 }
1306
1307                 /// <summary>
1308                 ///   Looks up members with name `name'.  If you provide an optional
1309                 ///   filter function, it'll only be called with members matching the
1310                 ///   requested member name.
1311                 ///
1312                 ///   This method will try to use the cache to do the lookup if possible.
1313                 ///
1314                 ///   Unlike other FindMembers implementations, this method will always
1315                 ///   check all inherited members - even when called on an interface type.
1316                 ///
1317                 ///   If you know that you're only looking for methods, you should use
1318                 ///   MemberTypes.Method alone since this speeds up the lookup a bit.
1319                 ///   When doing a method-only search, it'll try to use a special method
1320                 ///   cache (unless it's a dynamic type or an interface) and the returned
1321                 ///   MemberInfo's will have the correct ReflectedType for inherited methods.
1322                 ///   The lookup process will automatically restart itself in method-only
1323                 ///   search mode if it discovers that it's about to return methods.
1324                 /// </summary>
1325                 ArrayList global = new ArrayList ();
1326                 bool using_global = false;
1327
1328                 public MemberList FindMembers (MemberTypes mt, BindingFlags bf, string name,
1329                                                MemberFilter filter, object criteria)
1330                 {
1331                         if (using_global)
1332                                 throw new Exception ();
1333
1334                         bool declared_only = (bf & BindingFlags.DeclaredOnly) != 0;
1335                         bool method_search = mt == MemberTypes.Method;
1336                         // If we have a method cache and we aren't already doing a method-only search,
1337                         // then we restart a method search if the first match is a method.
1338                         bool do_method_search = !method_search && (method_hash != null);
1339
1340                         ArrayList applicable;
1341
1342                         // If this is a method-only search, we try to use the method cache if
1343                         // possible; a lookup in the method cache will return a MemberInfo with
1344                         // the correct ReflectedType for inherited methods.
1345
1346                         if (method_search && (method_hash != null))
1347                                 applicable = (ArrayList) method_hash [name];
1348                         else
1349                                 applicable = (ArrayList) member_hash [name];
1350
1351                         if (applicable == null)
1352                                 return MemberList.Empty;
1353
1354                         //
1355                         // 32  slots gives 53 rss/54 size
1356                         // 2/4 slots gives 55 rss
1357                         //
1358                         // Strange: from 25,000 calls, only 1,800
1359                         // are above 2.  Why does this impact it?
1360                         //
1361                         global.Clear ();
1362                         using_global = true;
1363
1364                         Timer.StartTimer (TimerType.CachedLookup);
1365
1366                         EntryType type = GetEntryType (mt, bf);
1367
1368                         IMemberContainer current = Container;
1369
1370                         // `applicable' is a list of all members with the given member name `name'
1371                         // in the current class and all its parent classes.  The list is sorted in
1372                         // reverse order due to the way how the cache is initialy created (to speed
1373                         // things up, we're doing a deep-copy of our parent).
1374
1375                         for (int i = applicable.Count-1; i >= 0; i--) {
1376                                 CacheEntry entry = (CacheEntry) applicable [i];
1377
1378                                 // This happens each time we're walking one level up in the class
1379                                 // hierarchy.  If we're doing a DeclaredOnly search, we must abort
1380                                 // the first time this happens (this may already happen in the first
1381                                 // iteration of this loop if there are no members with the name we're
1382                                 // looking for in the current class).
1383                                 if (entry.Container != current) {
1384                                         if (declared_only || DoneSearching (global))
1385                                                 break;
1386
1387                                         current = entry.Container;
1388                                 }
1389
1390                                 // Is the member of the correct type ?
1391                                 if ((entry.EntryType & type & EntryType.MaskType) == 0)
1392                                         continue;
1393
1394                                 // Is the member static/non-static ?
1395                                 if ((entry.EntryType & type & EntryType.MaskStatic) == 0)
1396                                         continue;
1397
1398                                 // Apply the filter to it.
1399                                 if (filter (entry.Member, criteria)) {
1400                                         if ((entry.EntryType & EntryType.MaskType) != EntryType.Method)
1401                                                 do_method_search = false;
1402                                         global.Add (entry.Member);
1403                                 }
1404                         }
1405
1406                         Timer.StopTimer (TimerType.CachedLookup);
1407
1408                         // If we have a method cache and we aren't already doing a method-only
1409                         // search, we restart in method-only search mode if the first match is
1410                         // a method.  This ensures that we return a MemberInfo with the correct
1411                         // ReflectedType for inherited methods.
1412                         if (do_method_search && (global.Count > 0)){
1413                                 using_global = false;
1414
1415                                 return FindMembers (MemberTypes.Method, bf, name, filter, criteria);
1416                         }
1417
1418                         using_global = false;
1419                         MemberInfo [] copy = new MemberInfo [global.Count];
1420                         global.CopyTo (copy);
1421                         return new MemberList (copy);
1422                 }
1423         }
1424 }