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                         Expression 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 (!CheckAccessLevel (d.Type)) {
 338                                 Report. Error (122, loc,  "`" + d.Type + "' " +
 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 Expression 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                         Expression 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 ();
 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                                 t = (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                                 return t;
 588
 589                         //
 590                         // In case we are fed a composite name, normalize it.
 591                         //
 592                         int p = name.LastIndexOf ('.');
 593                         if (p != -1){
 594                                 ns = MakeFQN (ns, name.Substring (0, p));
 595                                 name = name.Substring (p+1);
 596                         }
 597
 598                         parent = RootContext.Tree.LookupByNamespace (ns, name);
 599                         if (parent == null)
 600                                 return null;
 601
 602                         t = parent.DefineType ();
 603                         dh.Insert (ns, name, t);
 604                         if (t == null){
 605                                 error = true;
 606                                 return null;
 607                         }
 608                         return t;
 609                 }
 610
 611                 public static void Error_AmbiguousTypeReference (Location loc, string name, Type t1, Type t2)
 612                 {
 613                         Report.Error (104, loc,
 614                                       String.Format ("`{0}' is an ambiguous reference ({1} or {2}) ", name,
 615                                                      t1.FullName, t2.FullName));
 616                 }
 617
 618                 /// <summary>
 619                 ///   GetType is used to resolve type names at the DeclSpace level.
 620                 ///   Use this to lookup class/struct bases, interface bases or
 621                 ///   delegate type references
 622                 /// </summary>
 623                 ///
 624                 /// <remarks>
 625                 ///   Contrast this to LookupType which is used inside method bodies to
 626                 ///   lookup types that have already been defined.  GetType is used
 627                 ///   during the tree resolution process and potentially define
 628                 ///   recursively the type
 629                 /// </remarks>
 630                 public Type FindType (Location loc, string name)
 631                 {
 632                         Type t;
 633                         bool error;
 634
 635                         //
 636                         // For the case the type we are looking for is nested within this one
 637                         // or is in any base class
 638                         //
 639                         DeclSpace containing_ds = this;
 640
 641                         while (containing_ds != null){
 642                                 Type container_type = containing_ds.TypeBuilder;
 643                                 Type current_type = container_type;
 644
 645                                 while (current_type != null) {
 646                                         string pre = current_type.FullName;
 647
 648                                         t = LookupInterfaceOrClass (pre, name, out error);
 649                                         if (error)
 650                                                 return null;
 651
 652                                         if ((t != null) && containing_ds.CheckAccessLevel (t))
 653                                                 return t;
 654
 655                                         current_type = current_type.BaseType;
 656                                 }
 657                                 containing_ds = containing_ds.Parent;
 658                         }
 659
 660                         //
 661                         // Attempt to lookup the class on our namespace and all it's implicit parents
 662                         //
 663                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.ImplicitParent) {
 664                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 665                                 if (error)
 666                                         return null;
 667
 668                                 if (t != null)
 669                                         return t;
 670                         }
 671
 672                         //
 673                         // Attempt to do a direct unqualified lookup
 674                         //
 675                         t = LookupInterfaceOrClass ("", name, out error);
 676                         if (error)
 677                                 return null;
 678
 679                         if (t != null)
 680                                 return t;
 681
 682                         //
 683                         // Attempt to lookup the class on any of the `using'
 684                         // namespaces
 685                         //
 686
 687                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.Parent){
 688
 689                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
 690                                 if (error)
 691                                         return null;
 692
 693                                 if (t != null)
 694                                         return t;
 695
 696                                 //
 697                                 // Now check the using clause list
 698                                 //
 699                                 Type match = null;
 700                                 foreach (Namespace using_ns in ns.GetUsingTable ()) {
 701                                         match = LookupInterfaceOrClass (using_ns.Name, name, out error);
 702                                         if (error)
 703                                                 return null;
 704
 705                                         if (match != null){
 706                                                 if (t != null){
 707                                                         if (CheckAccessLevel (match)) {
 708                                                                 Error_AmbiguousTypeReference (loc, name, t, match);
 709                                                                 return null;
 710                                                         }
 711                                                         continue;
 712                                                 }
 713
 714                                                 t = match;
 715                                         }
 716                                 }
 717                                 if (t != null)
 718                                         return t;
 719                         }
 720
 721                         //Report.Error (246, Location, "Can not find type `"+name+"'");
 722                         return null;
 723                 }
 724
 725                 /// <remarks>
 726                 ///   This function is broken and not what you're looking for.  It should only
 727                 ///   be used while the type is still being created since it doesn't use the cache
 728                 ///   and relies on the filter doing the member name check.
 729                 /// </remarks>
 730                 public abstract MemberList FindMembers (MemberTypes mt, BindingFlags bf,
 731                                                         MemberFilter filter, object criteria);
 732
 733                 /// <remarks>
 734                 ///   If we have a MemberCache, return it.  This property may return null if the
 735                 ///   class doesn't have a member cache or while it's still being created.
 736                 /// </remarks>
 737                 public abstract MemberCache MemberCache {
 738                         get;
 739                 }
 740         }
 741
 742         /// <summary>
 743         ///   This is a readonly list of MemberInfo's.
 744         /// </summary>
 745         public class MemberList : IList {
 746                 public readonly IList List;
 747                 int count;
 748
 749                 /// <summary>
 750                 ///   Create a new MemberList from the given IList.
 751                 /// </summary>
 752                 public MemberList (IList list)
 753                 {
 754                         if (list != null)
 755                                 this.List = list;
 756                         else
 757                                 this.List = new ArrayList ();
 758                         count = List.Count;
 759                 }
 760
 761                 /// <summary>
 762                 ///   Concatenate the ILists `first' and `second' to a new MemberList.
 763                 /// </summary>
 764                 public MemberList (IList first, IList second)
 765                 {
 766                         ArrayList list = new ArrayList ();
 767                         list.AddRange (first);
 768                         list.AddRange (second);
 769                         count = list.Count;
 770                         List = list;
 771                 }
 772
 773                 public static readonly MemberList Empty = new MemberList (new ArrayList ());
 774
 775                 /// <summary>
 776                 ///   Cast the MemberList into a MemberInfo[] array.
 777                 /// </summary>
 778                 /// <remarks>
 779                 ///   This is an expensive operation, only use it if it's really necessary.
 780                 /// </remarks>
 781                 public static explicit operator MemberInfo [] (MemberList list)
 782                 {
 783                         Timer.StartTimer (TimerType.MiscTimer);
 784                         MemberInfo [] result = new MemberInfo [list.Count];
 785                         list.CopyTo (result, 0);
 786                         Timer.StopTimer (TimerType.MiscTimer);
 787                         return result;
 788                 }
 789
 790                 // ICollection
 791
 792                 public int Count {
 793                         get {
 794                                 return count;
 795                         }
 796                 }
 797
 798                 public bool IsSynchronized {
 799                         get {
 800                                 return List.IsSynchronized;
 801                         }
 802                 }
 803
 804                 public object SyncRoot {
 805                         get {
 806                                 return List.SyncRoot;
 807                         }
 808                 }
 809
 810                 public void CopyTo (Array array, int index)
 811                 {
 812                         List.CopyTo (array, index);
 813                 }
 814
 815                 // IEnumerable
 816
 817                 public IEnumerator GetEnumerator ()
 818                 {
 819                         return List.GetEnumerator ();
 820                 }
 821
 822                 // IList
 823
 824                 public bool IsFixedSize {
 825                         get {
 826                                 return true;
 827                         }
 828                 }
 829
 830                 public bool IsReadOnly {
 831                         get {
 832                                 return true;
 833                         }
 834                 }
 835
 836                 object IList.this [int index] {
 837                         get {
 838                                 return List [index];
 839                         }
 840
 841                         set {
 842                                 throw new NotSupportedException ();
 843                         }
 844                 }
 845
 846                 // FIXME: try to find out whether we can avoid the cast in this indexer.
 847                 public MemberInfo this [int index] {
 848                         get {
 849                                 return (MemberInfo) List [index];
 850                         }
 851                 }
 852
 853                 public int Add (object value)
 854                 {
 855                         throw new NotSupportedException ();
 856                 }
 857
 858                 public void Clear ()
 859                 {
 860                         throw new NotSupportedException ();
 861                 }
 862
 863                 public bool Contains (object value)
 864                 {
 865                         return List.Contains (value);
 866                 }
 867
 868                 public int IndexOf (object value)
 869                 {
 870                         return List.IndexOf (value);
 871                 }
 872
 873                 public void Insert (int index, object value)
 874                 {
 875                         throw new NotSupportedException ();
 876                 }
 877
 878                 public void Remove (object value)
 879                 {
 880                         throw new NotSupportedException ();
 881                 }
 882
 883                 public void RemoveAt (int index)
 884                 {
 885                         throw new NotSupportedException ();
 886                 }
 887         }
 888
 889         /// <summary>
 890         ///   This interface is used to get all members of a class when creating the
 891         ///   member cache.  It must be implemented by all DeclSpace derivatives which
 892         ///   want to support the member cache and by TypeHandle to get caching of
 893         ///   non-dynamic types.
 894         /// </summary>
 895         public interface IMemberContainer {
 896                 /// <summary>
 897                 ///   The name of the IMemberContainer.  This is only used for
 898                 ///   debugging purposes.
 899                 /// </summary>
 900                 string Name {
 901                         get;
 902                 }
 903
 904                 /// <summary>
 905                 ///   The type of this IMemberContainer.
 906                 /// </summary>
 907                 Type Type {
 908                         get;
 909                 }
 910
 911                 /// <summary>
 912                 ///   Returns the IMemberContainer of the parent class or null if this
 913                 ///   is an interface or TypeManger.object_type.
 914                 ///   This is used when creating the member cache for a class to get all
 915                 ///   members from the parent class.
 916                 /// </summary>
 917                 IMemberContainer Parent {
 918                         get;
 919                 }
 920
 921                 /// <summary>
 922                 ///   Whether this is an interface.
 923                 /// </summary>
 924                 bool IsInterface {
 925                         get;
 926                 }
 927
 928                 /// <summary>
 929                 ///   Returns all members of this class with the corresponding MemberTypes
 930                 ///   and BindingFlags.
 931                 /// </summary>
 932                 /// <remarks>
 933                 ///   When implementing this method, make sure not to return any inherited
 934                 ///   members and check the MemberTypes and BindingFlags properly.
 935                 ///   Unfortunately, System.Reflection is lame and doesn't provide a way to
 936                 ///   get the BindingFlags (static/non-static,public/non-public) in the
 937                 ///   MemberInfo class, but the cache needs this information.  That's why
 938                 ///   this method is called multiple times with different BindingFlags.
 939                 /// </remarks>
 940                 MemberList GetMembers (MemberTypes mt, BindingFlags bf);
 941
 942                 /// <summary>
 943                 ///   Return the container's member cache.
 944                 /// </summary>
 945                 MemberCache MemberCache {
 946                         get;
 947                 }
 948         }
 949
 950         /// <summary>
 951         ///   The MemberCache is used by dynamic and non-dynamic types to speed up
 952         ///   member lookups.  It has a member name based hash table; it maps each member
 953         ///   name to a list of CacheEntry objects.  Each CacheEntry contains a MemberInfo
 954         ///   and the BindingFlags that were initially used to get it.  The cache contains
 955         ///   all members of the current class and all inherited members.  If this cache is
 956         ///   for an interface types, it also contains all inherited members.
 957         ///
 958         ///   There are two ways to get a MemberCache:
 959         ///   * if this is a dynamic type, lookup the corresponding DeclSpace and then
 960         ///     use the DeclSpace.MemberCache property.
 961         ///   * if this not a dynamic type, call TypeHandle.GetTypeHandle() to get a
 962         ///     TypeHandle instance for the type and then use TypeHandle.MemberCache.
 963         /// </summary>
 964         public class MemberCache {
 965                 public readonly IMemberContainer Container;
 966                 protected Hashtable member_hash;
 967                 protected Hashtable method_hash;
 968                 protected Hashtable interface_hash;
 969
 970                 /// <summary>
 971                 ///   Create a new MemberCache for the given IMemberContainer `container'.
 972                 /// </summary>
 973                 public MemberCache (IMemberContainer container)
 974                 {
 975                         this.Container = container;
 976
 977                         Timer.IncrementCounter (CounterType.MemberCache);
 978                         Timer.StartTimer (TimerType.CacheInit);
 979
 980                         interface_hash = new Hashtable ();
 981
 982                         // If we have a parent class (we have a parent class unless we're
 983                         // TypeManager.object_type), we deep-copy its MemberCache here.
 984                         if (Container.IsInterface) {
 985                                 MemberCache parent;
 986                                 if (Container.Parent != null)
 987                                         parent = Container.Parent.MemberCache;
 988                                 else
 989                                         parent = TypeHandle.ObjectType.MemberCache;
 990                                 member_hash = SetupCacheForInterface (parent);
 991                         } else if (Container.Parent != null)
 992                                 member_hash = SetupCache (Container.Parent.MemberCache);
 993                         else
 994                                 member_hash = new Hashtable ();
 995
 996                         // If this is neither a dynamic type nor an interface, create a special
 997                         // method cache with all declared and inherited methods.
 998                         Type type = container.Type;
 999                         if (!(type is TypeBuilder) && !type.IsInterface) {
1000                                 method_hash = new Hashtable ();
1001                                 AddMethods (type);
1002                         }
1003
1004                         // Add all members from the current class.
1005                         AddMembers (Container);
1006
1007                         Timer.StopTimer (TimerType.CacheInit);
1008                 }
1009
1010                 /// <summary>
1011                 ///   Bootstrap this member cache by doing a deep-copy of our parent.
1012                 /// </summary>
1013                 Hashtable SetupCache (MemberCache parent)
1014                 {
1015                         Hashtable hash = new Hashtable ();
1016
1017                         IDictionaryEnumerator it = parent.member_hash.GetEnumerator ();
1018                         while (it.MoveNext ()) {
1019                                 hash [it.Key] = ((ArrayList) it.Value).Clone ();
1020                         }
1021
1022                         return hash;
1023                 }
1024
1025                 void AddInterfaces (MemberCache parent)
1026                 {
1027                         foreach (Type iface in parent.interface_hash.Keys) {
1028                                 if (!interface_hash.Contains (iface))
1029                                         interface_hash.Add (iface, true);
1030                         }
1031                 }
1032
1033                 /// <summary>
1034                 ///   Add the contents of `new_hash' to `hash'.
1035                 /// </summary>
1036                 void AddHashtable (Hashtable hash, Hashtable new_hash)
1037                 {
1038                         IDictionaryEnumerator it = new_hash.GetEnumerator ();
1039                         while (it.MoveNext ()) {
1040                                 ArrayList list = (ArrayList) hash [it.Key];
1041                                 if (list != null)
1042                                         list.AddRange ((ArrayList) it.Value);
1043                                 else
1044                                         hash [it.Key] = ((ArrayList) it.Value).Clone ();
1045                         }
1046                 }
1047
1048                 /// <summary>
1049                 ///   Bootstrap the member cache for an interface type.
1050                 ///   Type.GetMembers() won't return any inherited members for interface types,
1051                 ///   so we need to do this manually.  Interfaces also inherit from System.Object.
1052                 /// </summary>
1053                 Hashtable SetupCacheForInterface (MemberCache parent)
1054                 {
1055                         Hashtable hash = SetupCache (parent);
1056                         Type [] ifaces = TypeManager.GetInterfaces (Container.Type);
1057
1058                         foreach (Type iface in ifaces) {
1059                                 if (interface_hash.Contains (iface))
1060                                         continue;
1061                                 interface_hash.Add (iface, true);
1062
1063                                 IMemberContainer iface_container =
1064                                         TypeManager.LookupMemberContainer (iface);
1065
1066                                 MemberCache iface_cache = iface_container.MemberCache;
1067
1068                                 AddHashtable (hash, iface_cache.member_hash);
1069                                 AddInterfaces (iface_cache);
1070                         }
1071
1072                         return hash;
1073                 }
1074
1075                 /// <summary>
1076                 ///   Add all members from class `container' to the cache.
1077                 /// </summary>
1078                 void AddMembers (IMemberContainer container)
1079                 {
1080                         // We need to call AddMembers() with a single member type at a time
1081                         // to get the member type part of CacheEntry.EntryType right.
1082                         AddMembers (MemberTypes.Constructor, container);
1083                         AddMembers (MemberTypes.Field, container);
1084                         AddMembers (MemberTypes.Method, container);
1085                         AddMembers (MemberTypes.Property, container);
1086                         AddMembers (MemberTypes.Event, container);
1087                         // Nested types are returned by both Static and Instance searches.
1088                         AddMembers (MemberTypes.NestedType,
1089                                     BindingFlags.Static | BindingFlags.Public, container);
1090                         AddMembers (MemberTypes.NestedType,
1091                                     BindingFlags.Static | BindingFlags.NonPublic, container);
1092                 }
1093
1094                 void AddMembers (MemberTypes mt, IMemberContainer container)
1095                 {
1096                         AddMembers (mt, BindingFlags.Static | BindingFlags.Public, container);
1097                         AddMembers (mt, BindingFlags.Static | BindingFlags.NonPublic, container);
1098                         AddMembers (mt, BindingFlags.Instance | BindingFlags.Public, container);
1099                         AddMembers (mt, BindingFlags.Instance | BindingFlags.NonPublic, container);
1100                 }
1101
1102                 /// <summary>
1103                 ///   Add all members from class `container' with the requested MemberTypes and
1104                 ///   BindingFlags to the cache.  This method is called multiple times with different
1105                 ///   MemberTypes and BindingFlags.
1106                 /// </summary>
1107                 void AddMembers (MemberTypes mt, BindingFlags bf, IMemberContainer container)
1108                 {
1109                         MemberList members = container.GetMembers (mt, bf);
1110                         BindingFlags new_bf = (container == Container) ?
1111                                 bf | BindingFlags.DeclaredOnly : bf;
1112
1113                         foreach (MemberInfo member in members) {
1114                                 string name = member.Name;
1115
1116                                 // We use a name-based hash table of ArrayList's.
1117                                 ArrayList list = (ArrayList) member_hash [name];
1118                                 if (list == null) {
1119                                         list = new ArrayList ();
1120                                         member_hash.Add (name, list);
1121                                 }
1122
1123                                 // When this method is called for the current class, the list will
1124                                 // already contain all inherited members from our parent classes.
1125                                 // We cannot add new members in front of the list since this'd be an
1126                                 // expensive operation, that's why the list is sorted in reverse order
1127                                 // (ie. members from the current class are coming last).
1128                                 list.Add (new CacheEntry (container, member, mt, bf));
1129                         }
1130                 }
1131
1132                 /// <summary>
1133                 ///   Add all declared and inherited methods from class `type' to the method cache.
1134                 /// </summary>
1135                 void AddMethods (Type type)
1136                 {
1137                         AddMethods (BindingFlags.Static | BindingFlags.Public |
1138                                     BindingFlags.FlattenHierarchy, type);
1139                         AddMethods (BindingFlags.Static | BindingFlags.NonPublic |
1140                                     BindingFlags.FlattenHierarchy, type);
1141                         AddMethods (BindingFlags.Instance | BindingFlags.Public, type);
1142                         AddMethods (BindingFlags.Instance | BindingFlags.NonPublic, type);
1143                 }
1144
1145                 void AddMethods (BindingFlags bf, Type type)
1146                 {
1147                         MemberInfo [] members = type.GetMethods (bf);
1148
1149                         Array.Reverse (members);
1150
1151                         foreach (MethodBase member in members) {
1152                                 string name = member.Name;
1153
1154                                 // Varargs methods aren't allowed in C# code.
1155                                 if ((member.CallingConvention & CallingConventions.VarArgs) != 0)
1156                                         continue;
1157
1158                                 // We use a name-based hash table of ArrayList's.
1159                                 ArrayList list = (ArrayList) method_hash [name];
1160                                 if (list == null) {
1161                                         list = new ArrayList ();
1162                                         method_hash.Add (name, list);
1163                                 }
1164
1165                                 // Unfortunately, the elements returned by Type.GetMethods() aren't
1166                                 // sorted so we need to do this check for every member.
1167                                 BindingFlags new_bf = bf;
1168                                 if (member.DeclaringType == type)
1169                                         new_bf |= BindingFlags.DeclaredOnly;
1170
1171                                 list.Add (new CacheEntry (Container, member, MemberTypes.Method, new_bf));
1172                         }
1173
1174
1175                 }
1176
1177                 /// <summary>
1178                 ///   Compute and return a appropriate `EntryType' magic number for the given
1179                 ///   MemberTypes and BindingFlags.
1180                 /// </summary>
1181                 protected static EntryType GetEntryType (MemberTypes mt, BindingFlags bf)
1182                 {
1183                         EntryType type = EntryType.None;
1184
1185                         if ((mt & MemberTypes.Constructor) != 0)
1186                                 type |= EntryType.Constructor;
1187                         if ((mt & MemberTypes.Event) != 0)
1188                                 type |= EntryType.Event;
1189                         if ((mt & MemberTypes.Field) != 0)
1190                                 type |= EntryType.Field;
1191                         if ((mt & MemberTypes.Method) != 0)
1192                                 type |= EntryType.Method;
1193                         if ((mt & MemberTypes.Property) != 0)
1194                                 type |= EntryType.Property;
1195                         // Nested types are returned by static and instance searches.
1196                         if ((mt & MemberTypes.NestedType) != 0)
1197                                 type |= EntryType.NestedType | EntryType.Static | EntryType.Instance;
1198
1199                         if ((bf & BindingFlags.Instance) != 0)
1200                                 type |= EntryType.Instance;
1201                         if ((bf & BindingFlags.Static) != 0)
1202                                 type |= EntryType.Static;
1203                         if ((bf & BindingFlags.Public) != 0)
1204                                 type |= EntryType.Public;
1205                         if ((bf & BindingFlags.NonPublic) != 0)
1206                                 type |= EntryType.NonPublic;
1207                         if ((bf & BindingFlags.DeclaredOnly) != 0)
1208                                 type |= EntryType.Declared;
1209
1210                         return type;
1211                 }
1212
1213                 /// <summary>
1214                 ///   The `MemberTypes' enumeration type is a [Flags] type which means that it may
1215                 ///   denote multiple member types.  Returns true if the given flags value denotes a
1216                 ///   single member types.
1217                 /// </summary>
1218                 public static bool IsSingleMemberType (MemberTypes mt)
1219                 {
1220                         switch (mt) {
1221                         case MemberTypes.Constructor:
1222                         case MemberTypes.Event:
1223                         case MemberTypes.Field:
1224                         case MemberTypes.Method:
1225                         case MemberTypes.Property:
1226                         case MemberTypes.NestedType:
1227                                 return true;
1228
1229                         default:
1230                                 return false;
1231                         }
1232                 }
1233
1234                 /// <summary>
1235                 ///   We encode the MemberTypes and BindingFlags of each members in a "magic"
1236                 ///   number to speed up the searching process.
1237                 /// </summary>
1238                 [Flags]
1239                 protected enum EntryType {
1240                         None            = 0x000,
1241
1242                         Instance        = 0x001,
1243                         Static          = 0x002,
1244                         MaskStatic      = Instance|Static,
1245
1246                         Public          = 0x004,
1247                         NonPublic       = 0x008,
1248                         MaskProtection  = Public|NonPublic,
1249
1250                         Declared        = 0x010,
1251
1252                         Constructor     = 0x020,
1253                         Event           = 0x040,
1254                         Field           = 0x080,
1255                         Method          = 0x100,
1256                         Property        = 0x200,
1257                         NestedType      = 0x400,
1258
1259                         MaskType        = Constructor|Event|Field|Method|Property|NestedType
1260                 }
1261
1262                 protected struct CacheEntry {
1263                         public readonly IMemberContainer Container;
1264                         public readonly EntryType EntryType;
1265                         public readonly MemberInfo Member;
1266
1267                         public CacheEntry (IMemberContainer container, MemberInfo member,
1268                                            MemberTypes mt, BindingFlags bf)
1269                         {
1270                                 this.Container = container;
1271                                 this.Member = member;
1272                                 this.EntryType = GetEntryType (mt, bf);
1273                         }
1274                 }
1275
1276                 /// <summary>
1277                 ///   This is called each time we're walking up one level in the class hierarchy
1278                 ///   and checks whether we can abort the search since we've already found what
1279                 ///   we were looking for.
1280                 /// </summary>
1281                 protected bool DoneSearching (ArrayList list)
1282                 {
1283                         //
1284                         // We've found exactly one member in the current class and it's not
1285                         // a method or constructor.
1286                         //
1287                         if (list.Count == 1 && !(list [0] is MethodBase))
1288                                 return true;
1289
1290                         //
1291                         // Multiple properties: we query those just to find out the indexer
1292                         // name
1293                         //
1294                         if ((list.Count > 0) && (list [0] is PropertyInfo))
1295                                 return true;
1296
1297                         return false;
1298                 }
1299
1300                 /// <summary>
1301                 ///   Looks up members with name `name'.  If you provide an optional
1302                 ///   filter function, it'll only be called with members matching the
1303                 ///   requested member name.
1304                 ///
1305                 ///   This method will try to use the cache to do the lookup if possible.
1306                 ///
1307                 ///   Unlike other FindMembers implementations, this method will always
1308                 ///   check all inherited members - even when called on an interface type.
1309                 ///
1310                 ///   If you know that you're only looking for methods, you should use
1311                 ///   MemberTypes.Method alone since this speeds up the lookup a bit.
1312                 ///   When doing a method-only search, it'll try to use a special method
1313                 ///   cache (unless it's a dynamic type or an interface) and the returned
1314                 ///   MemberInfo's will have the correct ReflectedType for inherited methods.
1315                 ///   The lookup process will automatically restart itself in method-only
1316                 ///   search mode if it discovers that it's about to return methods.
1317                 /// </summary>
1318                 ArrayList global = new ArrayList ();
1319                 bool using_global = false;
1320
1321                 public MemberList FindMembers (MemberTypes mt, BindingFlags bf, string name,
1322                                                MemberFilter filter, object criteria)
1323                 {
1324                         if (using_global)
1325                                 throw new Exception ();
1326
1327                         bool declared_only = (bf & BindingFlags.DeclaredOnly) != 0;
1328                         bool method_search = mt == MemberTypes.Method;
1329                         // If we have a method cache and we aren't already doing a method-only search,
1330                         // then we restart a method search if the first match is a method.
1331                         bool do_method_search = !method_search && (method_hash != null);
1332
1333                         ArrayList applicable;
1334
1335                         // If this is a method-only search, we try to use the method cache if
1336                         // possible; a lookup in the method cache will return a MemberInfo with
1337                         // the correct ReflectedType for inherited methods.
1338
1339                         if (method_search && (method_hash != null))
1340                                 applicable = (ArrayList) method_hash [name];
1341                         else
1342                                 applicable = (ArrayList) member_hash [name];
1343
1344                         if (applicable == null)
1345                                 return MemberList.Empty;
1346
1347                         //
1348                         // 32  slots gives 53 rss/54 size
1349                         // 2/4 slots gives 55 rss
1350                         //
1351                         // Strange: from 25,000 calls, only 1,800
1352                         // are above 2.  Why does this impact it?
1353                         //
1354                         global.Clear ();
1355                         using_global = true;
1356
1357                         Timer.StartTimer (TimerType.CachedLookup);
1358
1359                         EntryType type = GetEntryType (mt, bf);
1360
1361                         IMemberContainer current = Container;
1362
1363                         // `applicable' is a list of all members with the given member name `name'
1364                         // in the current class and all its parent classes.  The list is sorted in
1365                         // reverse order due to the way how the cache is initialy created (to speed
1366                         // things up, we're doing a deep-copy of our parent).
1367
1368                         for (int i = applicable.Count-1; i >= 0; i--) {
1369                                 CacheEntry entry = (CacheEntry) applicable [i];
1370
1371                                 // This happens each time we're walking one level up in the class
1372                                 // hierarchy.  If we're doing a DeclaredOnly search, we must abort
1373                                 // the first time this happens (this may already happen in the first
1374                                 // iteration of this loop if there are no members with the name we're
1375                                 // looking for in the current class).
1376                                 if (entry.Container != current) {
1377                                         if (declared_only || DoneSearching (global))
1378                                                 break;
1379
1380                                         current = entry.Container;
1381                                 }
1382
1383                                 // Is the member of the correct type ?
1384                                 if ((entry.EntryType & type & EntryType.MaskType) == 0)
1385                                         continue;
1386
1387                                 // Is the member static/non-static ?
1388                                 if ((entry.EntryType & type & EntryType.MaskStatic) == 0)
1389                                         continue;
1390
1391                                 // Apply the filter to it.
1392                                 if (filter (entry.Member, criteria)) {
1393                                         if ((entry.EntryType & EntryType.MaskType) != EntryType.Method)
1394                                                 do_method_search = false;
1395                                         global.Add (entry.Member);
1396                                 }
1397                         }
1398
1399                         Timer.StopTimer (TimerType.CachedLookup);
1400
1401                         // If we have a method cache and we aren't already doing a method-only
1402                         // search, we restart in method-only search mode if the first match is
1403                         // a method.  This ensures that we return a MemberInfo with the correct
1404                         // ReflectedType for inherited methods.
1405                         if (do_method_search && (global.Count > 0)){
1406                                 using_global = false;
1407
1408                                 return FindMembers (MemberTypes.Method, bf, name, filter, criteria);
1409                         }
1410
1411                         using_global = false;
1412                         MemberInfo [] copy = new MemberInfo [global.Count];
1413                         global.CopyTo (copy);
1414                         return new MemberList (copy);
1415                 }
1416         }
1417 }