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                         TypeManager.ResolveExpressionTypes (type_resolve_ec);
 315
 316                         return type_resolve_ec;
 317                 }
 318
 319                 // <summary>
 320                 //    Looks up the type, as parsed into the expression `e'
 321                 // </summary>
 322                 public Type ResolveType (Expression e, bool silent, Location loc)
 323                 {
 324                         if (type_resolve_ec == null)
 325                                 type_resolve_ec = GetTypeResolveEmitContext (parent, loc);
 326                         type_resolve_ec.loc = loc;
 327                         type_resolve_ec.ContainerType = TypeBuilder;
 328
 329                         int errors = Report.Errors;
 330                         TypeExpr d = e.ResolveAsTypeTerminal (type_resolve_ec);
 331
 332                         if (d == null || d.eclass != ExprClass.Type){
 333                                 if (!silent && errors == Report.Errors){
 334                                         Report.Error (246, loc, "Cannot find type `"+ e.ToString () +"'");
 335                                 }
 336                                 return null;
 337                         }
 338
 339                         if (!d.CheckAccessLevel (this)) {
 340                                 Report. Error (122, loc,  "`" + d.Name + "' " +
 341                                        "is inaccessible because of its protection level");
 342                                 return null;
 343                         }
 344
 345                         return d.Type;
 346                 }
 347
 348                 // <summary>
 349                 //    Resolves the expression `e' for a type, and will recursively define
 350                 //    types.
 351                 // </summary>
 352                 public TypeExpr ResolveTypeExpr (Expression e, bool silent, Location loc)
 353                 {
 354                         if (type_resolve_ec == null)
 355                                 type_resolve_ec = GetTypeResolveEmitContext (parent, loc);
 356                         type_resolve_ec.loc = loc;
 357                         type_resolve_ec.ContainerType = TypeBuilder;
 358
 359                         TypeExpr d = e.ResolveAsTypeTerminal (type_resolve_ec);
 360
 361                         if (d == null || d.eclass != ExprClass.Type){
 362                                 if (!silent){
 363                                         Report.Error (246, loc, "Cannot find type `"+ e +"'");
 364                                 }
 365                                 return null;
 366                         }
 367
 368                         return d;
 369                 }
 370
 371                 public bool CheckAccessLevel (Type check_type)
 372                 {
 373                         if (check_type == TypeBuilder)
 374                                 return true;
 375
 376                         TypeAttributes check_attr = check_type.Attributes & TypeAttributes.VisibilityMask;
 377
 378                         //
 379                         // Broken Microsoft runtime, return public for arrays, no matter what
 380                         // the accessibility is for their underlying class, and they return
 381                         // NonPublic visibility for pointers
 382                         //
 383                         if (check_type.IsArray || check_type.IsPointer)
 384                                 return CheckAccessLevel (TypeManager.GetElementType (check_type));
 385
 386                         switch (check_attr){
 387                         case TypeAttributes.Public:
 388                                 return true;
 389
 390                         case TypeAttributes.NotPublic:
 391                                 //
 392                                 // This test should probably use the declaringtype.
 393                                 //
 394                                 if (check_type.Assembly == TypeBuilder.Assembly){
 395                                         return true;
 396                                 }
 397                                 return false;
 398
 399                         case TypeAttributes.NestedPublic:
 400                                 return true;
 401
 402                         case TypeAttributes.NestedPrivate:
 403                                 string check_type_name = check_type.FullName;
 404                                 string type_name = TypeBuilder.FullName;
 405
 406                                 int cio = check_type_name.LastIndexOf ("+");
 407                                 string container = check_type_name.Substring (0, cio);
 408
 409                                 //
 410                                 // Check if the check_type is a nested class of the current type
 411                                 //
 412                                 if (check_type_name.StartsWith (type_name + "+")){
 413                                         return true;
 414                                 }
 415
 416                                 if (type_name.StartsWith (container)){
 417                                         return true;
 418                                 }
 419
 420                                 return false;
 421
 422                         case TypeAttributes.NestedFamily:
 423                                 //
 424                                 // Only accessible to methods in current type or any subtypes
 425                                 //
 426                                 return FamilyAccessible (check_type);
 427
 428                         case TypeAttributes.NestedFamANDAssem:
 429                                 return (check_type.Assembly == TypeBuilder.Assembly) &&
 430                                         FamilyAccessible (check_type);
 431
 432                         case TypeAttributes.NestedFamORAssem:
 433                                 return (check_type.Assembly == TypeBuilder.Assembly) ||
 434                                         FamilyAccessible (check_type);
 435
 436                         case TypeAttributes.NestedAssembly:
 437                                 return check_type.Assembly == TypeBuilder.Assembly;
 438                         }
 439
 440                         Console.WriteLine ("HERE: " + check_attr);
 441                         return false;
 442
 443                 }
 444
 445                 protected bool FamilyAccessible (Type check_type)
 446                 {
 447                         Type declaring = check_type.DeclaringType;
 448                         if (TypeBuilder.IsSubclassOf (declaring))
 449                                 return true;
 450
 451                         string check_type_name = check_type.FullName;
 452                         string type_name = TypeBuilder.FullName;
 453
 454                         int cio = check_type_name.LastIndexOf ("+");
 455                         string container = check_type_name.Substring (0, cio);
 456
 457                         //
 458                         // Check if the check_type is a nested class of the current type
 459                         //
 460                         if (check_type_name.StartsWith (container + "+"))
 461                                 return true;
 462
 463                         return false;
 464                 }
 465
 466                 // Access level of a type.
 467                 enum AccessLevel {
 468                         Public                  = 0,
 469                         ProtectedInternal       = 1,
 470                         Internal                = 2,
 471                         Protected               = 3,
 472                         Private                 = 4
 473                 }
 474
 475                 // Check whether `flags' denotes a more restricted access than `level'
 476                 // and return the new level.
 477                 static AccessLevel CheckAccessLevel (AccessLevel level, int flags)
 478                 {
 479                         AccessLevel old_level = level;
 480
 481                         if ((flags & Modifiers.INTERNAL) != 0) {
 482                                 if ((flags & Modifiers.PROTECTED) != 0) {
 483                                         if ((int) level < (int) AccessLevel.ProtectedInternal)
 484                                                 level = AccessLevel.ProtectedInternal;
 485                                 } else {
 486                                         if ((int) level < (int) AccessLevel.Internal)
 487                                                 level = AccessLevel.Internal;
 488                                 }
 489                         } else if ((flags & Modifiers.PROTECTED) != 0) {
 490                                 if ((int) level < (int) AccessLevel.Protected)
 491                                         level = AccessLevel.Protected;
 492                         } else if ((flags & Modifiers.PRIVATE) != 0)
 493                                 level = AccessLevel.Private;
 494
 495                         return level;
 496                 }
 497
 498                 // Return the access level for a new member which is defined in the current
 499                 // TypeContainer with access modifiers `flags'.
 500                 AccessLevel GetAccessLevel (int flags)
 501                 {
 502                         if ((flags & Modifiers.PRIVATE) != 0)
 503                                 return AccessLevel.Private;
 504
 505                         AccessLevel level;
 506                         if (!IsTopLevel && (Parent != null))
 507                                 level = Parent.GetAccessLevel (flags);
 508                         else
 509                                 level = AccessLevel.Public;
 510
 511                         return CheckAccessLevel (CheckAccessLevel (level, flags), ModFlags);
 512                 }
 513
 514                 // Return the access level for type `t', but don't give more access than `flags'.
 515                 static AccessLevel GetAccessLevel (Type t, int flags)
 516                 {
 517                         if (((flags & Modifiers.PRIVATE) != 0) || t.IsNestedPrivate)
 518                                 return AccessLevel.Private;
 519
 520                         AccessLevel level;
 521                         if (TypeManager.IsBuiltinType (t))
 522                                 return AccessLevel.Public;
 523                         else if ((t.DeclaringType != null) && (t != t.DeclaringType))
 524                                 level = GetAccessLevel (t.DeclaringType, flags);
 525                         else {
 526                                 level = CheckAccessLevel (AccessLevel.Public, flags);
 527                         }
 528
 529                         if (t.IsNestedPublic)
 530                                 return level;
 531
 532                         if (t.IsNestedAssembly || t.IsNotPublic) {
 533                                 if ((int) level < (int) AccessLevel.Internal)
 534                                         level = AccessLevel.Internal;
 535                         }
 536
 537                         if (t.IsNestedFamily) {
 538                                 if ((int) level < (int) AccessLevel.Protected)
 539                                         level = AccessLevel.Protected;
 540                         }
 541
 542                         if (t.IsNestedFamORAssem) {
 543                                 if ((int) level < (int) AccessLevel.ProtectedInternal)
 544                                         level = AccessLevel.ProtectedInternal;
 545                         }
 546
 547                         return level;
 548                 }
 549
 550                 //
 551                 // Returns true if `parent' is as accessible as the flags `flags'
 552                 // given for this member.
 553                 //
 554                 public bool AsAccessible (Type parent, int flags)
 555                 {
 556                         while (parent.IsArray || parent.IsPointer || parent.IsByRef)
 557                                 parent = TypeManager.GetElementType (parent);
 558
 559                         AccessLevel level = GetAccessLevel (flags);
 560                         AccessLevel level2 = GetAccessLevel (parent, flags);
 561
 562                         return (int) level >= (int) level2;
 563                 }
 564
 565                 static DoubleHash dh = new DoubleHash ();
 566
 567                 Type LookupInterfaceOrClass (string ns, string name, out bool error)
 568                 {
 569                         DeclSpace parent;
 570                         Type t;
 571                         object r;
 572
 573                         error = false;
 574
 575                         if (dh.Lookup (ns, name, out r))
 576                                 t = (Type) r;
 577                         else {
 578                                 if (ns != ""){
 579                                         if (Namespace.IsNamespace (ns)){
 580                                                 string fullname = (ns != "") ? ns + "." + name : name;
 581                                                 t = TypeManager.LookupType (fullname);
 582                                         } else
 583                                                 t = null;
 584                                 } else
 585                                         t = TypeManager.LookupType (name);
 586                         }
 587
 588                         if (t != null)
 589                                 return t;
 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                                 return null;
 603
 604                         t = parent.DefineType ();
 605                         dh.Insert (ns, name, t);
 606                         if (t == null){
 607                                 error = true;
 608                                 return null;
 609                         }
 610                         return t;
 611                 }
 612
 613                 public static void Error_AmbiguousTypeReference (Location loc, string name, Type t1, Type t2)
 614                 {
 615                         Report.Error (104, loc,
 616                                       String.Format ("`{0}' is an ambiguous reference ({1} or {2}) ", name,
 617                                                      t1.FullName, t2.FullName));
 618                 }
 619
 620                 /// <summary>
 621                 ///   GetType is used to resolve type names at the DeclSpace level.
 622                 ///   Use this to lookup class/struct bases, interface bases or
 623                 ///   delegate type references
 624                 /// </summary>
 625                 ///
 626                 /// <remarks>
 627                 ///   Contrast this to LookupType which is used inside method bodies to
 628                 ///   lookup types that have already been defined.  GetType is used
 629                 ///   during the tree resolution process and potentially define
 630                 ///   recursively the type
 631                 /// </remarks>
 632                 public Type FindType (Location loc, string name)
 633                 {
 634                         Type t;
 635                         bool error;
 636
 637                         //
 638                         // For the case the type we are looking for is nested within this one
 639                         // or is in any base class
 640                         //
 641                         DeclSpace containing_ds = this;
 642
 643                         while (containing_ds != null){
 644                                 Type container_type = containing_ds.TypeBuilder;
 645                                 Type current_type = container_type;
 646
 647                                 while (current_type != null) {
 648                                         string pre = current_type.FullName;
 649
 650                                         t = LookupInterfaceOrClass (pre, name, out error);
 651                                         if (error)
 652                                                 return null;
 653
 654                                         if ((t != null) && containing_ds.CheckAccessLevel (t))
 655                                                 return t;
 656
 657                                         current_type = current_type.BaseType;
 658                                 }
 659                                 containing_ds = containing_ds.Parent;
 660                         }
 661
 662                         //
 663                         // Attempt to lookup the class on our namespace and all it's implicit parents
 664                         //
 665                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.ImplicitParent) {
 666                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 667                                 if (error)
 668                                         return null;
 669
 670                                 if (t != null)
 671                                         return t;
 672                         }
 673
 674                         //
 675                         // Attempt to do a direct unqualified lookup
 676                         //
 677                         t = LookupInterfaceOrClass ("", name, out error);
 678                         if (error)
 679                                 return null;
 680
 681                         if (t != null)
 682                                 return t;
 683
 684                         //
 685                         // Attempt to lookup the class on any of the `using'
 686                         // namespaces
 687                         //
 688
 689                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.Parent){
 690
 691                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 692                                 if (error)
 693                                         return null;
 694
 695                                 if (t != null)
 696                                         return t;
 697
 698                                 //
 699                                 // Now check the using clause list
 700                                 //
 701                                 Type match = null;
 702                                 foreach (Namespace using_ns in ns.GetUsingTable ()) {
 703                                         match = LookupInterfaceOrClass (using_ns.Name, name, out error);
 704                                         if (error)
 705                                                 return null;
 706
 707                                         if (match != null){
 708                                                 if (t != null){
 709                                                         if (CheckAccessLevel (match)) {
 710                                                                 Error_AmbiguousTypeReference (loc, name, t, match);
 711                                                                 return null;
 712                                                         }
 713                                                         continue;
 714                                                 }
 715
 716                                                 t = match;
 717                                         }
 718                                 }
 719                                 if (t != null)
 720                                         return t;
 721                         }
 722
 723                         //Report.Error (246, Location, "Can not find type `"+name+"'");
 724                         return null;
 725                 }
 726
 727                 /// <remarks>
 728                 ///   This function is broken and not what you're looking for.  It should only
 729                 ///   be used while the type is still being created since it doesn't use the cache
 730                 ///   and relies on the filter doing the member name check.
 731                 /// </remarks>
 732                 public abstract MemberList FindMembers (MemberTypes mt, BindingFlags bf,
 733                                                         MemberFilter filter, object criteria);
 734
 735                 /// <remarks>
 736                 ///   If we have a MemberCache, return it.  This property may return null if the
 737                 ///   class doesn't have a member cache or while it's still being created.
 738                 /// </remarks>
 739                 public abstract MemberCache MemberCache {
 740                         get;
 741                 }
 742         }
 743
 744         /// <summary>
 745         ///   This is a readonly list of MemberInfo's.
 746         /// </summary>
 747         public class MemberList : IList {
 748                 public readonly IList List;
 749                 int count;
 750
 751                 /// <summary>
 752                 ///   Create a new MemberList from the given IList.
 753                 /// </summary>
 754                 public MemberList (IList list)
 755                 {
 756                         if (list != null)
 757                                 this.List = list;
 758                         else
 759                                 this.List = new ArrayList ();
 760                         count = List.Count;
 761                 }
 762
 763                 /// <summary>
 764                 ///   Concatenate the ILists `first' and `second' to a new MemberList.
 765                 /// </summary>
 766                 public MemberList (IList first, IList second)
 767                 {
 768                         ArrayList list = new ArrayList ();
 769                         list.AddRange (first);
 770                         list.AddRange (second);
 771                         count = list.Count;
 772                         List = list;
 773                 }
 774
 775                 public static readonly MemberList Empty = new MemberList (new ArrayList ());
 776
 777                 /// <summary>
 778                 ///   Cast the MemberList into a MemberInfo[] array.
 779                 /// </summary>
 780                 /// <remarks>
 781                 ///   This is an expensive operation, only use it if it's really necessary.
 782                 /// </remarks>
 783                 public static explicit operator MemberInfo [] (MemberList list)
 784                 {
 785                         Timer.StartTimer (TimerType.MiscTimer);
 786                         MemberInfo [] result = new MemberInfo [list.Count];
 787                         list.CopyTo (result, 0);
 788                         Timer.StopTimer (TimerType.MiscTimer);
 789                         return result;
 790                 }
 791
 792                 // ICollection
 793
 794                 public int Count {
 795                         get {
 796                                 return count;
 797                         }
 798                 }
 799
 800                 public bool IsSynchronized {
 801                         get {
 802                                 return List.IsSynchronized;
 803                         }
 804                 }
 805
 806                 public object SyncRoot {
 807                         get {
 808                                 return List.SyncRoot;
 809                         }
 810                 }
 811
 812                 public void CopyTo (Array array, int index)
 813                 {
 814                         List.CopyTo (array, index);
 815                 }
 816
 817                 // IEnumerable
 818
 819                 public IEnumerator GetEnumerator ()
 820                 {
 821                         return List.GetEnumerator ();
 822                 }
 823
 824                 // IList
 825
 826                 public bool IsFixedSize {
 827                         get {
 828                                 return true;
 829                         }
 830                 }
 831
 832                 public bool IsReadOnly {
 833                         get {
 834                                 return true;
 835                         }
 836                 }
 837
 838                 object IList.this [int index] {
 839                         get {
 840                                 return List [index];
 841                         }
 842
 843                         set {
 844                                 throw new NotSupportedException ();
 845                         }
 846                 }
 847
 848                 // FIXME: try to find out whether we can avoid the cast in this indexer.
 849                 public MemberInfo this [int index] {
 850                         get {
 851                                 return (MemberInfo) List [index];
 852                         }
 853                 }
 854
 855                 public int Add (object value)
 856                 {
 857                         throw new NotSupportedException ();
 858                 }
 859
 860                 public void Clear ()
 861                 {
 862                         throw new NotSupportedException ();
 863                 }
 864
 865                 public bool Contains (object value)
 866                 {
 867                         return List.Contains (value);
 868                 }
 869
 870                 public int IndexOf (object value)
 871                 {
 872                         return List.IndexOf (value);
 873                 }
 874
 875                 public void Insert (int index, object value)
 876                 {
 877                         throw new NotSupportedException ();
 878                 }
 879
 880                 public void Remove (object value)
 881                 {
 882                         throw new NotSupportedException ();
 883                 }
 884
 885                 public void RemoveAt (int index)
 886                 {
 887                         throw new NotSupportedException ();
 888                 }
 889         }
 890
 891         /// <summary>
 892         ///   This interface is used to get all members of a class when creating the
 893         ///   member cache.  It must be implemented by all DeclSpace derivatives which
 894         ///   want to support the member cache and by TypeHandle to get caching of
 895         ///   non-dynamic types.
 896         /// </summary>
 897         public interface IMemberContainer {
 898                 /// <summary>
 899                 ///   The name of the IMemberContainer.  This is only used for
 900                 ///   debugging purposes.
 901                 /// </summary>
 902                 string Name {
 903                         get;
 904                 }
 905
 906                 /// <summary>
 907                 ///   The type of this IMemberContainer.
 908                 /// </summary>
 909                 Type Type {
 910                         get;
 911                 }
 912
 913                 /// <summary>
 914                 ///   Returns the IMemberContainer of the parent class or null if this
 915                 ///   is an interface or TypeManger.object_type.
 916                 ///   This is used when creating the member cache for a class to get all
 917                 ///   members from the parent class.
 918                 /// </summary>
 919                 IMemberContainer Parent {
 920                         get;
 921                 }
 922
 923                 /// <summary>
 924                 ///   Whether this is an interface.
 925                 /// </summary>
 926                 bool IsInterface {
 927                         get;
 928                 }
 929
 930                 /// <summary>
 931                 ///   Returns all members of this class with the corresponding MemberTypes
 932                 ///   and BindingFlags.
 933                 /// </summary>
 934                 /// <remarks>
 935                 ///   When implementing this method, make sure not to return any inherited
 936                 ///   members and check the MemberTypes and BindingFlags properly.
 937                 ///   Unfortunately, System.Reflection is lame and doesn't provide a way to
 938                 ///   get the BindingFlags (static/non-static,public/non-public) in the
 939                 ///   MemberInfo class, but the cache needs this information.  That's why
 940                 ///   this method is called multiple times with different BindingFlags.
 941                 /// </remarks>
 942                 MemberList GetMembers (MemberTypes mt, BindingFlags bf);
 943
 944                 /// <summary>
 945                 ///   Return the container's member cache.
 946                 /// </summary>
 947                 MemberCache MemberCache {
 948                         get;
 949                 }
 950         }
 951
 952         /// <summary>
 953         ///   The MemberCache is used by dynamic and non-dynamic types to speed up
 954         ///   member lookups.  It has a member name based hash table; it maps each member
 955         ///   name to a list of CacheEntry objects.  Each CacheEntry contains a MemberInfo
 956         ///   and the BindingFlags that were initially used to get it.  The cache contains
 957         ///   all members of the current class and all inherited members.  If this cache is
 958         ///   for an interface types, it also contains all inherited members.
 959         ///
 960         ///   There are two ways to get a MemberCache:
 961         ///   * if this is a dynamic type, lookup the corresponding DeclSpace and then
 962         ///     use the DeclSpace.MemberCache property.
 963         ///   * if this not a dynamic type, call TypeHandle.GetTypeHandle() to get a
 964         ///     TypeHandle instance for the type and then use TypeHandle.MemberCache.
 965         /// </summary>
 966         public class MemberCache {
 967                 public readonly IMemberContainer Container;
 968                 protected Hashtable member_hash;
 969                 protected Hashtable method_hash;
 970                 protected Hashtable interface_hash;
 971
 972                 /// <summary>
 973                 ///   Create a new MemberCache for the given IMemberContainer `container'.
 974                 /// </summary>
 975                 public MemberCache (IMemberContainer container)
 976                 {
 977                         this.Container = container;
 978
 979                         Timer.IncrementCounter (CounterType.MemberCache);
 980                         Timer.StartTimer (TimerType.CacheInit);
 981
 982                         interface_hash = new Hashtable ();
 983
 984                         // If we have a parent class (we have a parent class unless we're
 985                         // TypeManager.object_type), we deep-copy its MemberCache here.
 986                         if (Container.IsInterface) {
 987                                 MemberCache parent;
 988                                 if (Container.Parent != null)
 989                                         parent = Container.Parent.MemberCache;
 990                                 else
 991                                         parent = TypeHandle.ObjectType.MemberCache;
 992                                 member_hash = SetupCacheForInterface (parent);
 993                         } else if (Container.Parent != null)
 994                                 member_hash = SetupCache (Container.Parent.MemberCache);
 995                         else
 996                                 member_hash = new Hashtable ();
 997
 998                         // If this is neither a dynamic type nor an interface, create a special
 999                         // method cache with all declared and inherited methods.
1000                         Type type = container.Type;
1001                         if (!(type is TypeBuilder) && !type.IsInterface) {
1002                                 method_hash = new Hashtable ();
1003                                 AddMethods (type);
1004                         }
1005
1006                         // Add all members from the current class.
1007                         AddMembers (Container);
1008
1009                         Timer.StopTimer (TimerType.CacheInit);
1010                 }
1011
1012                 /// <summary>
1013                 ///   Bootstrap this member cache by doing a deep-copy of our parent.
1014                 /// </summary>
1015                 Hashtable SetupCache (MemberCache parent)
1016                 {
1017                         Hashtable hash = new Hashtable ();
1018
1019                         IDictionaryEnumerator it = parent.member_hash.GetEnumerator ();
1020                         while (it.MoveNext ()) {
1021                                 hash [it.Key] = ((ArrayList) it.Value).Clone ();
1022                         }
1023
1024                         return hash;
1025                 }
1026
1027                 void AddInterfaces (MemberCache parent)
1028                 {
1029                         foreach (Type iface in parent.interface_hash.Keys) {
1030                                 if (!interface_hash.Contains (iface))
1031                                         interface_hash.Add (iface, true);
1032                         }
1033                 }
1034
1035                 /// <summary>
1036                 ///   Add the contents of `new_hash' to `hash'.
1037                 /// </summary>
1038                 void AddHashtable (Hashtable hash, Hashtable new_hash)
1039                 {
1040                         IDictionaryEnumerator it = new_hash.GetEnumerator ();
1041                         while (it.MoveNext ()) {
1042                                 ArrayList list = (ArrayList) hash [it.Key];
1043                                 if (list != null)
1044                                         list.AddRange ((ArrayList) it.Value);
1045                                 else
1046                                         hash [it.Key] = ((ArrayList) it.Value).Clone ();
1047                         }
1048                 }
1049
1050                 /// <summary>
1051                 ///   Bootstrap the member cache for an interface type.
1052                 ///   Type.GetMembers() won't return any inherited members for interface types,
1053                 ///   so we need to do this manually.  Interfaces also inherit from System.Object.
1054                 /// </summary>
1055                 Hashtable SetupCacheForInterface (MemberCache parent)
1056                 {
1057                         Hashtable hash = SetupCache (parent);
1058                         TypeExpr [] ifaces = TypeManager.GetInterfaces (Container.Type);
1059
1060                         foreach (TypeExpr iface in ifaces) {
1061                                 Type itype = iface.Type;
1062
1063                                 if (interface_hash.Contains (itype))
1064                                         continue;
1065                                 interface_hash.Add (itype, true);
1066
1067                                 IMemberContainer iface_container =
1068                                         TypeManager.LookupMemberContainer (itype);
1069
1070                                 MemberCache iface_cache = iface_container.MemberCache;
1071
1072                                 AddHashtable (hash, iface_cache.member_hash);
1073                                 AddInterfaces (iface_cache);
1074                         }
1075
1076                         return hash;
1077                 }
1078
1079                 /// <summary>
1080                 ///   Add all members from class `container' to the cache.
1081                 /// </summary>
1082                 void AddMembers (IMemberContainer container)
1083                 {
1084                         // We need to call AddMembers() with a single member type at a time
1085                         // to get the member type part of CacheEntry.EntryType right.
1086                         AddMembers (MemberTypes.Constructor, container);
1087                         AddMembers (MemberTypes.Field, container);
1088                         AddMembers (MemberTypes.Method, container);
1089                         AddMembers (MemberTypes.Property, container);
1090                         AddMembers (MemberTypes.Event, container);
1091                         // Nested types are returned by both Static and Instance searches.
1092                         AddMembers (MemberTypes.NestedType,
1093                                     BindingFlags.Static | BindingFlags.Public, container);
1094                         AddMembers (MemberTypes.NestedType,
1095                                     BindingFlags.Static | BindingFlags.NonPublic, container);
1096                 }
1097
1098                 void AddMembers (MemberTypes mt, IMemberContainer container)
1099                 {
1100                         AddMembers (mt, BindingFlags.Static | BindingFlags.Public, container);
1101                         AddMembers (mt, BindingFlags.Static | BindingFlags.NonPublic, container);
1102                         AddMembers (mt, BindingFlags.Instance | BindingFlags.Public, container);
1103                         AddMembers (mt, BindingFlags.Instance | BindingFlags.NonPublic, container);
1104                 }
1105
1106                 /// <summary>
1107                 ///   Add all members from class `container' with the requested MemberTypes and
1108                 ///   BindingFlags to the cache.  This method is called multiple times with different
1109                 ///   MemberTypes and BindingFlags.
1110                 /// </summary>
1111                 void AddMembers (MemberTypes mt, BindingFlags bf, IMemberContainer container)
1112                 {
1113                         MemberList members = container.GetMembers (mt, bf);
1114                         BindingFlags new_bf = (container == Container) ?
1115                                 bf | BindingFlags.DeclaredOnly : bf;
1116
1117                         foreach (MemberInfo member in members) {
1118                                 string name = member.Name;
1119
1120                                 // We use a name-based hash table of ArrayList's.
1121                                 ArrayList list = (ArrayList) member_hash [name];
1122                                 if (list == null) {
1123                                         list = new ArrayList ();
1124                                         member_hash.Add (name, list);
1125                                 }
1126
1127                                 // When this method is called for the current class, the list will
1128                                 // already contain all inherited members from our parent classes.
1129                                 // We cannot add new members in front of the list since this'd be an
1130                                 // expensive operation, that's why the list is sorted in reverse order
1131                                 // (ie. members from the current class are coming last).
1132                                 list.Add (new CacheEntry (container, member, mt, bf));
1133                         }
1134                 }
1135
1136                 /// <summary>
1137                 ///   Add all declared and inherited methods from class `type' to the method cache.
1138                 /// </summary>
1139                 void AddMethods (Type type)
1140                 {
1141                         AddMethods (BindingFlags.Static | BindingFlags.Public |
1142                                     BindingFlags.FlattenHierarchy, type);
1143                         AddMethods (BindingFlags.Static | BindingFlags.NonPublic |
1144                                     BindingFlags.FlattenHierarchy, type);
1145                         AddMethods (BindingFlags.Instance | BindingFlags.Public, type);
1146                         AddMethods (BindingFlags.Instance | BindingFlags.NonPublic, type);
1147                 }
1148
1149                 void AddMethods (BindingFlags bf, Type type)
1150                 {
1151                         MemberInfo [] members = type.GetMethods (bf);
1152
1153                         Array.Reverse (members);
1154
1155                         foreach (MethodBase member in members) {
1156                                 string name = member.Name;
1157
1158                                 // Varargs methods aren't allowed in C# code.
1159                                 if ((member.CallingConvention & CallingConventions.VarArgs) != 0)
1160                                         continue;
1161
1162                                 // We use a name-based hash table of ArrayList's.
1163                                 ArrayList list = (ArrayList) method_hash [name];
1164                                 if (list == null) {
1165                                         list = new ArrayList ();
1166                                         method_hash.Add (name, list);
1167                                 }
1168
1169                                 // Unfortunately, the elements returned by Type.GetMethods() aren't
1170                                 // sorted so we need to do this check for every member.
1171                                 BindingFlags new_bf = bf;
1172                                 if (member.DeclaringType == type)
1173                                         new_bf |= BindingFlags.DeclaredOnly;
1174
1175                                 list.Add (new CacheEntry (Container, member, MemberTypes.Method, new_bf));
1176                         }
1177
1178
1179                 }
1180
1181                 /// <summary>
1182                 ///   Compute and return a appropriate `EntryType' magic number for the given
1183                 ///   MemberTypes and BindingFlags.
1184                 /// </summary>
1185                 protected static EntryType GetEntryType (MemberTypes mt, BindingFlags bf)
1186                 {
1187                         EntryType type = EntryType.None;
1188
1189                         if ((mt & MemberTypes.Constructor) != 0)
1190                                 type |= EntryType.Constructor;
1191                         if ((mt & MemberTypes.Event) != 0)
1192                                 type |= EntryType.Event;
1193                         if ((mt & MemberTypes.Field) != 0)
1194                                 type |= EntryType.Field;
1195                         if ((mt & MemberTypes.Method) != 0)
1196                                 type |= EntryType.Method;
1197                         if ((mt & MemberTypes.Property) != 0)
1198                                 type |= EntryType.Property;
1199                         // Nested types are returned by static and instance searches.
1200                         if ((mt & MemberTypes.NestedType) != 0)
1201                                 type |= EntryType.NestedType | EntryType.Static | EntryType.Instance;
1202
1203                         if ((bf & BindingFlags.Instance) != 0)
1204                                 type |= EntryType.Instance;
1205                         if ((bf & BindingFlags.Static) != 0)
1206                                 type |= EntryType.Static;
1207                         if ((bf & BindingFlags.Public) != 0)
1208                                 type |= EntryType.Public;
1209                         if ((bf & BindingFlags.NonPublic) != 0)
1210                                 type |= EntryType.NonPublic;
1211                         if ((bf & BindingFlags.DeclaredOnly) != 0)
1212                                 type |= EntryType.Declared;
1213
1214                         return type;
1215                 }
1216
1217                 /// <summary>
1218                 ///   The `MemberTypes' enumeration type is a [Flags] type which means that it may
1219                 ///   denote multiple member types.  Returns true if the given flags value denotes a
1220                 ///   single member types.
1221                 /// </summary>
1222                 public static bool IsSingleMemberType (MemberTypes mt)
1223                 {
1224                         switch (mt) {
1225                         case MemberTypes.Constructor:
1226                         case MemberTypes.Event:
1227                         case MemberTypes.Field:
1228                         case MemberTypes.Method:
1229                         case MemberTypes.Property:
1230                         case MemberTypes.NestedType:
1231                                 return true;
1232
1233                         default:
1234                                 return false;
1235                         }
1236                 }
1237
1238                 /// <summary>
1239                 ///   We encode the MemberTypes and BindingFlags of each members in a "magic"
1240                 ///   number to speed up the searching process.
1241                 /// </summary>
1242                 [Flags]
1243                 protected enum EntryType {
1244                         None            = 0x000,
1245
1246                         Instance        = 0x001,
1247                         Static          = 0x002,
1248                         MaskStatic      = Instance|Static,
1249
1250                         Public          = 0x004,
1251                         NonPublic       = 0x008,
1252                         MaskProtection  = Public|NonPublic,
1253
1254                         Declared        = 0x010,
1255
1256                         Constructor     = 0x020,
1257                         Event           = 0x040,
1258                         Field           = 0x080,
1259                         Method          = 0x100,
1260                         Property        = 0x200,
1261                         NestedType      = 0x400,
1262
1263                         MaskType        = Constructor|Event|Field|Method|Property|NestedType
1264                 }
1265
1266                 protected struct CacheEntry {
1267                         public readonly IMemberContainer Container;
1268                         public readonly EntryType EntryType;
1269                         public readonly MemberInfo Member;
1270
1271                         public CacheEntry (IMemberContainer container, MemberInfo member,
1272                                            MemberTypes mt, BindingFlags bf)
1273                         {
1274                                 this.Container = container;
1275                                 this.Member = member;
1276                                 this.EntryType = GetEntryType (mt, bf);
1277                         }
1278                 }
1279
1280                 /// <summary>
1281                 ///   This is called each time we're walking up one level in the class hierarchy
1282                 ///   and checks whether we can abort the search since we've already found what
1283                 ///   we were looking for.
1284                 /// </summary>
1285                 protected bool DoneSearching (ArrayList list)
1286                 {
1287                         //
1288                         // We've found exactly one member in the current class and it's not
1289                         // a method or constructor.
1290                         //
1291                         if (list.Count == 1 && !(list [0] is MethodBase))
1292                                 return true;
1293
1294                         //
1295                         // Multiple properties: we query those just to find out the indexer
1296                         // name
1297                         //
1298                         if ((list.Count > 0) && (list [0] is PropertyInfo))
1299                                 return true;
1300
1301                         return false;
1302                 }
1303
1304                 /// <summary>
1305                 ///   Looks up members with name `name'.  If you provide an optional
1306                 ///   filter function, it'll only be called with members matching the
1307                 ///   requested member name.
1308                 ///
1309                 ///   This method will try to use the cache to do the lookup if possible.
1310                 ///
1311                 ///   Unlike other FindMembers implementations, this method will always
1312                 ///   check all inherited members - even when called on an interface type.
1313                 ///
1314                 ///   If you know that you're only looking for methods, you should use
1315                 ///   MemberTypes.Method alone since this speeds up the lookup a bit.
1316                 ///   When doing a method-only search, it'll try to use a special method
1317                 ///   cache (unless it's a dynamic type or an interface) and the returned
1318                 ///   MemberInfo's will have the correct ReflectedType for inherited methods.
1319                 ///   The lookup process will automatically restart itself in method-only
1320                 ///   search mode if it discovers that it's about to return methods.
1321                 /// </summary>
1322                 ArrayList global = new ArrayList ();
1323                 bool using_global = false;
1324
1325                 public MemberList FindMembers (MemberTypes mt, BindingFlags bf, string name,
1326                                                MemberFilter filter, object criteria)
1327                 {
1328                         if (using_global)
1329                                 throw new Exception ();
1330
1331                         bool declared_only = (bf & BindingFlags.DeclaredOnly) != 0;
1332                         bool method_search = mt == MemberTypes.Method;
1333                         // If we have a method cache and we aren't already doing a method-only search,
1334                         // then we restart a method search if the first match is a method.
1335                         bool do_method_search = !method_search && (method_hash != null);
1336
1337                         ArrayList applicable;
1338
1339                         // If this is a method-only search, we try to use the method cache if
1340                         // possible; a lookup in the method cache will return a MemberInfo with
1341                         // the correct ReflectedType for inherited methods.
1342
1343                         if (method_search && (method_hash != null))
1344                                 applicable = (ArrayList) method_hash [name];
1345                         else
1346                                 applicable = (ArrayList) member_hash [name];
1347
1348                         if (applicable == null)
1349                                 return MemberList.Empty;
1350
1351                         //
1352                         // 32  slots gives 53 rss/54 size
1353                         // 2/4 slots gives 55 rss
1354                         //
1355                         // Strange: from 25,000 calls, only 1,800
1356                         // are above 2.  Why does this impact it?
1357                         //
1358                         global.Clear ();
1359                         using_global = true;
1360
1361                         Timer.StartTimer (TimerType.CachedLookup);
1362
1363                         EntryType type = GetEntryType (mt, bf);
1364
1365                         IMemberContainer current = Container;
1366
1367                         // `applicable' is a list of all members with the given member name `name'
1368                         // in the current class and all its parent classes.  The list is sorted in
1369                         // reverse order due to the way how the cache is initialy created (to speed
1370                         // things up, we're doing a deep-copy of our parent).
1371
1372                         for (int i = applicable.Count-1; i >= 0; i--) {
1373                                 CacheEntry entry = (CacheEntry) applicable [i];
1374
1375                                 // This happens each time we're walking one level up in the class
1376                                 // hierarchy.  If we're doing a DeclaredOnly search, we must abort
1377                                 // the first time this happens (this may already happen in the first
1378                                 // iteration of this loop if there are no members with the name we're
1379                                 // looking for in the current class).
1380                                 if (entry.Container != current) {
1381                                         if (declared_only || DoneSearching (global))
1382                                                 break;
1383
1384                                         current = entry.Container;
1385                                 }
1386
1387                                 // Is the member of the correct type ?
1388                                 if ((entry.EntryType & type & EntryType.MaskType) == 0)
1389                                         continue;
1390
1391                                 // Is the member static/non-static ?
1392                                 if ((entry.EntryType & type & EntryType.MaskStatic) == 0)
1393                                         continue;
1394
1395                                 // Apply the filter to it.
1396                                 if (filter (entry.Member, criteria)) {
1397                                         if ((entry.EntryType & EntryType.MaskType) != EntryType.Method)
1398                                                 do_method_search = false;
1399                                         global.Add (entry.Member);
1400                                 }
1401                         }
1402
1403                         Timer.StopTimer (TimerType.CachedLookup);
1404
1405                         // If we have a method cache and we aren't already doing a method-only
1406                         // search, we restart in method-only search mode if the first match is
1407                         // a method.  This ensures that we return a MemberInfo with the correct
1408                         // ReflectedType for inherited methods.
1409                         if (do_method_search && (global.Count > 0)){
1410                                 using_global = false;
1411
1412                                 return FindMembers (MemberTypes.Method, bf, name, filter, criteria);
1413                         }
1414
1415                         using_global = false;
1416                         MemberInfo [] copy = new MemberInfo [global.Count];
1417                         global.CopyTo (copy);
1418                         return new MemberList (copy);
1419                 }
1420         }
1421 }