mcs/gmcs/attribute.cs

   1 //
   2 // attribute.cs: Attribute Handler
   3 //
   4 // Author: Ravi Pratap (ravi@ximian.com)
   5 //         Marek Safar (marek.safar@seznam.cz)
   6 //
   7 // Licensed under the terms of the GNU GPL
   8 //
   9 // (C) 2001 Ximian, Inc (http://www.ximian.com)
  10 //
  11 //
  12
  13 using System;
  14 using System.Diagnostics;
  15 using System.Collections;
  16 using System.Collections.Specialized;
  17 using System.Reflection;
  18 using System.Reflection.Emit;
  19 using System.Runtime.InteropServices;
  20 using System.Runtime.CompilerServices;
  21 using System.Security;
  22 using System.Security.Permissions;
  23 using System.Text;
  24
  25 namespace Mono.CSharp {
  26
  27         /// <summary>
  28         ///   Base class for objects that can have Attributes applied to them.
  29         /// </summary>
  30         public abstract class Attributable {
  31                 /// <summary>
  32                 ///   Attributes for this type
  33                 /// </summary>
  34                 Attributes attributes;
  35
  36                 public Attributable (Attributes attrs)
  37                 {
  38                         attributes = attrs;
  39                 }
  40
  41                 public Attributes OptAttributes
  42                 {
  43                         get {
  44                                 return attributes;
  45                         }
  46                         set {
  47                                 attributes = value;
  48                         }
  49                 }
  50
  51                 /// <summary>
  52                 /// Use member-specific procedure to apply attribute @a in @cb to the entity being built in @builder
  53                 /// </summary>
  54                 public abstract void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb);
  55
  56                 /// <summary>
  57                 /// Returns one AttributeTarget for this element.
  58                 /// </summary>
  59                 public abstract AttributeTargets AttributeTargets { get; }
  60
  61                 public abstract bool IsClsCompliaceRequired (DeclSpace ds);
  62
  63                 /// <summary>
  64                 /// Gets list of valid attribute targets for explicit target declaration.
  65                 /// The first array item is default target. Don't break this rule.
  66                 /// </summary>
  67                 public abstract string[] ValidAttributeTargets { get; }
  68         };
  69
  70         public class Attribute {
  71                 public readonly string ExplicitTarget;
  72                 public AttributeTargets Target;
  73
  74                 public readonly string    Name;
  75                 public readonly Expression LeftExpr;
  76                 public readonly string Identifier;
  77
  78                 public readonly ArrayList Arguments;
  79
  80                 public readonly Location Location;
  81
  82                 public Type Type;
  83
  84                 bool resolve_error;
  85
  86                 // Is non-null if type is AttributeUsageAttribute
  87                 AttributeUsageAttribute usage_attribute;
  88
  89                 public AttributeUsageAttribute UsageAttribute {
  90                         get {
  91                                 return usage_attribute;
  92                         }
  93                 }
  94
  95                 MethodImplOptions ImplOptions;
  96                 UnmanagedType     UnmanagedType;
  97                 CustomAttributeBuilder cb;
  98
  99                 // non-null if named args present after Resolve () is called
 100                 PropertyInfo [] prop_info_arr;
 101                 FieldInfo [] field_info_arr;
 102                 object [] field_values_arr;
 103                 object [] prop_values_arr;
 104                 object [] pos_values;
 105
 106                 static PtrHashtable usage_attr_cache = new PtrHashtable ();
 107
 108                 public Attribute (string target, Expression left_expr, string identifier, ArrayList args, Location loc)
 109                 {
 110                         LeftExpr = left_expr;
 111                         Identifier = identifier;
 112                         Name = LeftExpr == null ? identifier : LeftExpr + "." + identifier;
 113                         Arguments = args;
 114                         Location = loc;
 115                         ExplicitTarget = target;
 116                 }
 117
 118                 void Error_InvalidNamedArgument (string name)
 119                 {
 120                         Report.Error (617, Location, "Invalid attribute argument: '{0}'.  Argument must be fields " +
 121                                       "fields which are not readonly, static or const;  or read-write instance properties.",
 122                                       name);
 123                 }
 124
 125                 static void Error_AttributeArgumentNotValid (string extra, Location loc)
 126                 {
 127                         Report.Error (182, loc,
 128                                       "An attribute argument must be a constant expression, typeof " +
 129                                       "expression or array creation expression" + extra);
 130                 }
 131
 132                 static void Error_AttributeArgumentNotValid (Location loc)
 133                 {
 134                         Error_AttributeArgumentNotValid ("", loc);
 135                 }
 136
 137                 static void Error_TypeParameterInAttribute (Location loc)
 138                 {
 139                         Report.Error (
 140                                 -202, loc, "Can not use a type parameter in an attribute");
 141                 }
 142
 143                 /// <summary>
 144                 /// This is rather hack. We report many emit attribute error with same error to be compatible with
 145                 /// csc. But because csc has to report them this way because error came from ilasm we needn't.
 146                 /// </summary>
 147                 public void Error_AttributeEmitError (string inner)
 148                 {
 149                         Report.Error (647, Location, "Error emitting '{0}' attribute because '{1}'", Name, inner);
 150                 }
 151
 152                 public void Error_InvalidSecurityParent ()
 153                 {
 154                         Error_AttributeEmitError ("it is attached to invalid parent");
 155                 }
 156
 157                 void Error_AttributeConstructorMismatch ()
 158                 {
 159                         Report.Error (-6, Location,
 160                                       "Could not find a constructor for this argument list.");
 161                 }
 162
 163                 void ResolvePossibleAttributeTypes (EmitContext ec, out Type t1, out Type t2)
 164                 {
 165                         t1 = null;
 166                         t2 = null;
 167
 168                         FullNamedExpression n1 = null;
 169                         FullNamedExpression n2 = null;
 170                         string IdentifierAttribute = Identifier + "Attribute";
 171                         if (LeftExpr == null) {
 172                                 n1 = new SimpleName (Identifier, Location).ResolveAsTypeStep (ec);
 173
 174                                 // FIXME: Shouldn't do this for quoted attributes: [@A]
 175                                 n2 = new SimpleName (IdentifierAttribute, Location).ResolveAsTypeStep (ec);
 176                         } else {
 177                                 FullNamedExpression l = LeftExpr.ResolveAsTypeStep (ec);
 178                                 if (l == null) {
 179                                         Report.Error (246, Location, "Couldn't find namespace or type '{0}'", LeftExpr);
 180                                         return;
 181                                 }
 182                                 n1 = new MemberAccess (l, Identifier, Location).ResolveNamespaceOrType (ec, true);
 183
 184                                 // FIXME: Shouldn't do this for quoted attributes: [X.@A]
 185                                 n2 = new MemberAccess (l, IdentifierAttribute, Location).ResolveNamespaceOrType (ec, true);
 186                         }
 187
 188                         TypeExpr te1 = n1 == null ? null : n1 as TypeExpr;
 189                         TypeExpr te2 = n2 == null ? null : n2 as TypeExpr;
 190
 191                         if (te1 != null)
 192                                 t1 = te1.ResolveType (ec);
 193                         if (te2 != null)
 194                                 t2 = te2.ResolveType (ec);
 195                 }
 196
 197                 /// <summary>
 198                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 199                 /// </summary>
 200                 Type CheckAttributeType (EmitContext ec)
 201                 {
 202                         Type t1, t2;
 203                         ResolvePossibleAttributeTypes (ec, out t1, out t2);
 204
 205                         string NameAttribute = Name + "Attribute";
 206
 207                         String err0616 = null;
 208                         if (t1 != null && ! t1.IsSubclassOf (TypeManager.attribute_type)) {
 209                                 t1 = null;
 210                                 err0616 = "'" + Name + "': is not an attribute class";
 211                         }
 212                         if (t2 != null && ! t2.IsSubclassOf (TypeManager.attribute_type)) {
 213                                 t2 = null;
 214                                 err0616 = (err0616 != null)
 215                                         ? "Neither '" + Name + "' nor '" + NameAttribute +"' is an attribute class"
 216                                         : "'" + Name + "Attribute': is not an attribute class";
 217                         }
 218
 219                         if (t1 != null && t2 != null) {
 220                                 Report.Error(1614, Location, "'" + Name + "': is ambiguous; "
 221                                              + " use either '@" + Name + "' or '" + NameAttribute + "'");
 222                                 return null;
 223                         }
 224                         if (t1 != null)
 225                                 return t1;
 226                         if (t2 != null)
 227                                 return t2;
 228                         if (err0616 != null) {
 229                                 Report.Error (616, Location, err0616);
 230                                 return null;
 231                         }
 232
 233                         Report.Error (246, Location,
 234                                       "Could not find attribute '" + Name
 235                                       + "' (are you missing a using directive or an assembly reference ?)");
 236
 237                         resolve_error = true;
 238                         return null;
 239                 }
 240
 241                 public virtual Type ResolveType (EmitContext ec)
 242                 {
 243                         if (Type == null)
 244                                 Type = CheckAttributeType (ec);
 245                         return Type;
 246                 }
 247
 248                 /// <summary>
 249                 ///   Validates the guid string
 250                 /// </summary>
 251                 bool ValidateGuid (string guid)
 252                 {
 253                         try {
 254                                 new Guid (guid);
 255                                 return true;
 256                         } catch {
 257                                 Report.Error (647, Location, "Format of GUID is invalid: " + guid);
 258                                 return false;
 259                         }
 260                 }
 261
 262                 string GetFullMemberName (string member)
 263                 {
 264                         return Type.FullName + '.' + member;
 265                 }
 266
 267                 //
 268                 // Given an expression, if the expression is a valid attribute-argument-expression
 269                 // returns an object that can be used to encode it, or null on failure.
 270                 //
 271                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, Type arg_type, out object result)
 272                 {
 273                         if (e is EnumConstant) {
 274                                 if (RootContext.StdLib)
 275                                         result = ((EnumConstant)e).GetValueAsEnumType ();
 276                                 else
 277                                         result = ((EnumConstant)e).GetValue ();
 278
 279                                 return true;
 280                         }
 281
 282                         Constant constant = e as Constant;
 283                         if (constant != null) {
 284                                 if (e.Type != arg_type) {
 285                                         constant = Const.ChangeType (loc, constant, arg_type);
 286                                         if (constant == null) {
 287                                                 result = null;
 288                                                 Error_AttributeArgumentNotValid (loc);
 289                                                 return false;
 290                                         }
 291                                 }
 292                                 result = constant.GetValue ();
 293                                 return true;
 294                         } else if (e is TypeOf) {
 295                                 result = ((TypeOf) e).TypeArg;
 296                                 return true;
 297                         } else if (e is ArrayCreation){
 298                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();
 299                                 if (result != null)
 300                                         return true;
 301                         } else if (e is EmptyCast) {
 302                                 Expression child = ((EmptyCast)e).Child;
 303                                 return GetAttributeArgumentExpression (child, loc, child.Type, out result);
 304                         }
 305
 306                         result = null;
 307                         Error_AttributeArgumentNotValid (loc);
 308                         return false;
 309                 }
 310
 311                 public virtual CustomAttributeBuilder Resolve (EmitContext ec)
 312                 {
 313                         if (resolve_error)
 314                                 return null;
 315
 316                         resolve_error = true;
 317
 318                         Type oldType = Type;
 319
 320                         // Sanity check.
 321                         Type = CheckAttributeType (ec);
 322
 323                         if (oldType == null && Type == null)
 324                                 return null;
 325                         if (oldType != null && oldType != Type){
 326                                 Report.Error (-27, Location,
 327                                               "Attribute {0} resolved to different types at different times: {1} vs. {2}",
 328                                               Name, oldType, Type);
 329                                 return null;
 330                         }
 331
 332                         if (Type.IsAbstract) {
 333                                 Report.Error (653, Location, "Cannot apply attribute class '{0}' because it is abstract", Name);
 334                                 return null;
 335                         }
 336
 337                         bool MethodImplAttr = false;
 338                         bool MarshalAsAttr = false;
 339                         bool GuidAttr = false;
 340                         bool usage_attr = false;
 341
 342                         bool DoCompares = true;
 343
 344                         //
 345                         // If we are a certain special attribute, we
 346                         // set the information accordingly
 347                         //
 348
 349                         if (Type == TypeManager.attribute_usage_type)
 350                                 usage_attr = true;
 351                         else if (Type == TypeManager.methodimpl_attr_type)
 352                                 MethodImplAttr = true;
 353                         else if (Type == TypeManager.marshal_as_attr_type)
 354                                 MarshalAsAttr = true;
 355                         else if (Type == TypeManager.guid_attr_type)
 356                                 GuidAttr = true;
 357                         else
 358                                 DoCompares = false;
 359
 360                         // Now we extract the positional and named arguments
 361
 362                         ArrayList pos_args = new ArrayList ();
 363                         ArrayList named_args = new ArrayList ();
 364                         int pos_arg_count = 0;
 365
 366                         if (Arguments != null) {
 367                                 pos_args = (ArrayList) Arguments [0];
 368                                 if (pos_args != null)
 369                                         pos_arg_count = pos_args.Count;
 370                                 if (Arguments.Count > 1)
 371                                         named_args = (ArrayList) Arguments [1];
 372                         }
 373
 374                         pos_values = new object [pos_arg_count];
 375
 376                         //
 377                         // First process positional arguments
 378                         //
 379
 380                         int i;
 381                         for (i = 0; i < pos_arg_count; i++) {
 382                                 Argument a = (Argument) pos_args [i];
 383                                 Expression e;
 384
 385                                 if (!a.Resolve (ec, Location))
 386                                         return null;
 387
 388                                 e = a.Expr;
 389
 390                                 object val;
 391                                 if (!GetAttributeArgumentExpression (e, Location, a.Type, out val))
 392                                         return null;
 393
 394                                 pos_values [i] = val;
 395
 396                                 if (DoCompares){
 397                                         if (usage_attr) {
 398                                                 if ((int)val == 0) {
 399                                                         Report.Error (591, Location, "Invalid value for argument to 'System.AttributeUsage' attribute");
 400                                                         return null;
 401                                                 }
 402                                                 usage_attribute = new AttributeUsageAttribute ((AttributeTargets)val);
 403                                         } else if (MethodImplAttr) {
 404                                                 this.ImplOptions = (MethodImplOptions) val;
 405                                         } else if (GuidAttr){
 406                                                 //
 407                                                 // we will later check the validity of the type
 408                                                 //
 409                                                 if (val is string){
 410                                                         if (!ValidateGuid ((string) val))
 411                                                                 return null;
 412                                                 }
 413
 414                                         } else if (MarshalAsAttr)
 415                                                 this.UnmanagedType =
 416                                                 (System.Runtime.InteropServices.UnmanagedType) val;
 417                                 }
 418                         }
 419
 420                         //
 421                         // Now process named arguments
 422                         //
 423
 424                         ArrayList field_infos = null;
 425                         ArrayList prop_infos  = null;
 426                         ArrayList field_values = null;
 427                         ArrayList prop_values = null;
 428
 429                         if (named_args.Count > 0) {
 430                                 field_infos = new ArrayList ();
 431                                 prop_infos  = new ArrayList ();
 432                                 field_values = new ArrayList ();
 433                                 prop_values = new ArrayList ();
 434                         }
 435
 436                         Hashtable seen_names = new Hashtable();
 437
 438                         for (i = 0; i < named_args.Count; i++) {
 439                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 440                                 string member_name = (string) de.Key;
 441                                 Argument a  = (Argument) de.Value;
 442                                 Expression e;
 443
 444                                 if (seen_names.Contains(member_name)) {
 445                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 446                                         return null;
 447                                 }
 448                                 seen_names.Add(member_name, 1);
 449
 450                                 if (!a.Resolve (ec, Location))
 451                                         return null;
 452
 453                                 Expression member = Expression.MemberLookup (
 454                                         ec, Type, member_name,
 455                                         MemberTypes.Field | MemberTypes.Property,
 456                                         BindingFlags.Public | BindingFlags.Instance,
 457                                         Location);
 458
 459                                 if (member == null) {
 460                                         member = Expression.MemberLookup (ec, Type, member_name,
 461                                                 MemberTypes.Field | MemberTypes.Property, BindingFlags.NonPublic | BindingFlags.Instance,
 462                                                 Location);
 463
 464                                         if (member != null) {
 465                                                 Report.Error (122, Location, "'{0}' is inaccessible due to its protection level", GetFullMemberName (member_name));
 466                                                 return null;
 467                                         }
 468                                 }
 469
 470                                 if (member == null){
 471                                         Report.Error (117, Location, "Attribute `{0}' does not contain a definition for `{1}'",
 472                                                       Type, member_name);
 473                                         return null;
 474                                 }
 475
 476                                 if (!(member is PropertyExpr || member is FieldExpr)) {
 477                                         Error_InvalidNamedArgument (member_name);
 478                                         return null;
 479                                 }
 480
 481                                 e = a.Expr;
 482                                 if (e is TypeParameterExpr){
 483                                         Error_TypeParameterInAttribute (Location);
 484                                         return null;
 485                                 }
 486
 487                                 if (member is PropertyExpr) {
 488                                         PropertyExpr pe = (PropertyExpr) member;
 489                                         PropertyInfo pi = pe.PropertyInfo;
 490
 491                                         if (!pi.CanWrite || !pi.CanRead) {
 492                                                 Report.SymbolRelatedToPreviousError (pi);
 493                                                 Error_InvalidNamedArgument (member_name);
 494                                                 return null;
 495                                         }
 496
 497                                         object value;
 498                                         if (!GetAttributeArgumentExpression (e, Location, pi.PropertyType, out value))
 499                                                                 return null;
 500
 501                                                 if (usage_attribute != null) {
 502                                                         if (member_name == "AllowMultiple")
 503                                                         usage_attribute.AllowMultiple = (bool) value;
 504                                                         if (member_name == "Inherited")
 505                                                         usage_attribute.Inherited = (bool) value;
 506                                         }
 507
 508                                         prop_values.Add (value);
 509                                         prop_infos.Add (pi);
 510
 511                                 } else if (member is FieldExpr) {
 512                                         FieldExpr fe = (FieldExpr) member;
 513                                         FieldInfo fi = fe.FieldInfo;
 514
 515                                         if (fi.IsInitOnly) {
 516                                                 Error_InvalidNamedArgument (member_name);
 517                                                 return null;
 518                                         }
 519
 520                                         object value;
 521                                         if (!GetAttributeArgumentExpression (e, Location, fi.FieldType, out value))
 522                                                 return null;
 523
 524                                         field_values.Add (value);
 525
 526                                         field_infos.Add (fi);
 527                                 }
 528                         }
 529
 530                         Expression mg = Expression.MemberLookup (
 531                                 ec, Type, ".ctor", MemberTypes.Constructor,
 532                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 533                                 Location);
 534
 535                         if (mg == null) {
 536                                 Error_AttributeConstructorMismatch ();
 537                                 return null;
 538                         }
 539
 540                         MethodBase constructor = Invocation.OverloadResolve (
 541                                 ec, (MethodGroupExpr) mg, pos_args, false, Location);
 542
 543                         if (constructor == null) {
 544                                 return null;
 545                         }
 546
 547                         //
 548                         // Now we perform some checks on the positional args as they
 549                         // cannot be null for a constructor which expects a parameter
 550                         // of type object
 551                         //
 552
 553                         ParameterData pd = TypeManager.GetParameterData (constructor);
 554
 555                         int last_real_param = pd.Count;
 556                         if (pd.HasParams) {
 557                                 // When the params is not filled we need to put one
 558                                 if (last_real_param > pos_arg_count) {
 559                                         object [] new_pos_values = new object [pos_arg_count + 1];
 560                                         pos_values.CopyTo (new_pos_values, 0);
 561                                         new_pos_values [pos_arg_count] = new object [] {} ;
 562                                         pos_values = new_pos_values;
 563                                 }
 564                                 last_real_param--;
 565                         }
 566
 567                         for (int j = 0; j < pos_arg_count; ++j) {
 568                                 Argument a = (Argument) pos_args [j];
 569
 570                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {
 571                                         Error_AttributeArgumentNotValid (Location);
 572                                         return null;
 573                                 }
 574
 575                                 if (j < last_real_param)
 576                                         continue;
 577
 578                                 if (j == last_real_param) {
 579                                         object [] array = new object [pos_arg_count - last_real_param];
 580                                         array [0] = pos_values [j];
 581                                         pos_values [j] = array;
 582                                         continue;
 583                                 }
 584
 585                                 object [] params_array = (object []) pos_values [last_real_param];
 586                                 params_array [j - last_real_param] = pos_values [j];
 587                         }
 588
 589                         // Adjust the size of the pos_values if it had params
 590                         if (last_real_param != pos_arg_count) {
 591                                 object [] new_pos_values = new object [last_real_param + 1];
 592                                 Array.Copy (pos_values, new_pos_values, last_real_param + 1);
 593                                 pos_values = new_pos_values;
 594                         }
 595
 596                         try {
 597                                 if (named_args.Count > 0) {
 598                                         prop_info_arr = new PropertyInfo [prop_infos.Count];
 599                                         field_info_arr = new FieldInfo [field_infos.Count];
 600                                         field_values_arr = new object [field_values.Count];
 601                                         prop_values_arr = new object [prop_values.Count];
 602
 603                                         field_infos.CopyTo  (field_info_arr, 0);
 604                                         field_values.CopyTo (field_values_arr, 0);
 605
 606                                         prop_values.CopyTo  (prop_values_arr, 0);
 607                                         prop_infos.CopyTo   (prop_info_arr, 0);
 608
 609                                         cb = new CustomAttributeBuilder (
 610                                                 (ConstructorInfo) constructor, pos_values,
 611                                                 prop_info_arr, prop_values_arr,
 612                                                 field_info_arr, field_values_arr);
 613                                 }
 614                                 else
 615                                         cb = new CustomAttributeBuilder (
 616                                                 (ConstructorInfo) constructor, pos_values);
 617                         } catch (Exception e) {
 618                                 //
 619                                 // Sample:
 620                                 // using System.ComponentModel;
 621                                 // [DefaultValue (CollectionChangeAction.Add)]
 622                                 // class X { static void Main () {} }
 623                                 //
 624                                 Error_AttributeArgumentNotValid (Location);
 625                                 return null;
 626                         }
 627
 628                         resolve_error = false;
 629                         return cb;
 630                 }
 631
 632                 /// <summary>
 633                 ///   Get a string containing a list of valid targets for the attribute 'attr'
 634                 /// </summary>
 635                 public string GetValidTargets ()
 636                 {
 637                         StringBuilder sb = new StringBuilder ();
 638                         AttributeTargets targets = GetAttributeUsage ().ValidOn;
 639
 640                         if ((targets & AttributeTargets.Assembly) != 0)
 641                                 sb.Append ("'assembly' ");
 642
 643                         if ((targets & AttributeTargets.Class) != 0)
 644                                 sb.Append ("'class' ");
 645
 646                         if ((targets & AttributeTargets.Constructor) != 0)
 647                                 sb.Append ("'constructor' ");
 648
 649                         if ((targets & AttributeTargets.Delegate) != 0)
 650                                 sb.Append ("'delegate' ");
 651
 652                         if ((targets & AttributeTargets.Enum) != 0)
 653                                 sb.Append ("'enum' ");
 654
 655                         if ((targets & AttributeTargets.Event) != 0)
 656                                 sb.Append ("'event' ");
 657
 658                         if ((targets & AttributeTargets.Field) != 0)
 659                                 sb.Append ("'field' ");
 660
 661                         if ((targets & AttributeTargets.Interface) != 0)
 662                                 sb.Append ("'interface' ");
 663
 664                         if ((targets & AttributeTargets.Method) != 0)
 665                                 sb.Append ("'method' ");
 666
 667                         if ((targets & AttributeTargets.Module) != 0)
 668                                 sb.Append ("'module' ");
 669
 670                         if ((targets & AttributeTargets.Parameter) != 0)
 671                                 sb.Append ("'parameter' ");
 672
 673                         if ((targets & AttributeTargets.Property) != 0)
 674                                 sb.Append ("'property' ");
 675
 676                         if ((targets & AttributeTargets.ReturnValue) != 0)
 677                                 sb.Append ("'return' ");
 678
 679                         if ((targets & AttributeTargets.Struct) != 0)
 680                                 sb.Append ("'struct' ");
 681
 682                         return sb.ToString ();
 683
 684                 }
 685
 686                 /// <summary>
 687                 /// Returns AttributeUsage attribute for this type
 688                 /// </summary>
 689                 public AttributeUsageAttribute GetAttributeUsage ()
 690                 {
 691                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 692                         if (ua != null)
 693                                 return ua;
 694
 695                         Class attr_class = TypeManager.LookupClass (Type);
 696
 697                         if (attr_class == null) {
 698                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 699                                 ua = (AttributeUsageAttribute)usage_attr [0];
 700                                 usage_attr_cache.Add (Type, ua);
 701                                 return ua;
 702                         }
 703
 704                         return attr_class.AttributeUsage;
 705                 }
 706
 707                 /// <summary>
 708                 /// Returns custom name of indexer
 709                 /// </summary>
 710                 public string GetIndexerAttributeValue (EmitContext ec)
 711                 {
 712                         if (pos_values == null)
 713                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 714                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 715                                 Resolve (ec);
 716
 717                         return pos_values [0] as string;
 718                 }
 719
 720                 /// <summary>
 721                 /// Returns condition of ConditionalAttribute
 722                 /// </summary>
 723                 public string GetConditionalAttributeValue (EmitContext ec)
 724                 {
 725                         if (pos_values == null)
 726                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 727                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 728                                 Resolve (ec);
 729
 730                         // Some error occurred
 731                         if (pos_values [0] == null)
 732                                 return null;
 733
 734                         return (string)pos_values [0];
 735                 }
 736
 737                 /// <summary>
 738                 /// Creates the instance of ObsoleteAttribute from this attribute instance
 739                 /// </summary>
 740                 public ObsoleteAttribute GetObsoleteAttribute (EmitContext ec)
 741                 {
 742                         if (pos_values == null)
 743                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 744                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 745                                 Resolve (ec);
 746
 747                         // Some error occurred
 748                         if (pos_values == null)
 749                                 return null;
 750
 751                         if (pos_values.Length == 0)
 752                                 return new ObsoleteAttribute ();
 753
 754                         if (pos_values.Length == 1)
 755                                 return new ObsoleteAttribute ((string)pos_values [0]);
 756
 757                         return new ObsoleteAttribute ((string)pos_values [0], (bool)pos_values [1]);
 758                 }
 759
 760                 /// <summary>
 761                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 762                 /// before ApplyAttribute. We need to resolve the arguments.
 763                 /// This situation occurs when class deps is differs from Emit order.
 764                 /// </summary>
 765                 public bool GetClsCompliantAttributeValue (EmitContext ec)
 766                 {
 767                         if (pos_values == null)
 768                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 769                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 770                                 Resolve (ec);
 771
 772                         // Some error occurred
 773                         if (pos_values [0] == null)
 774                                 return false;
 775
 776                         return (bool)pos_values [0];
 777                 }
 778
 779                 /// <summary>
 780                 /// Tests permitted SecurityAction for assembly or other types
 781                 /// </summary>
 782                 public bool CheckSecurityActionValidity (bool for_assembly)
 783                 {
 784                         SecurityAction action  = GetSecurityActionValue ();
 785
 786                         if ((action == SecurityAction.RequestMinimum || action == SecurityAction.RequestOptional || action == SecurityAction.RequestRefuse) && for_assembly)
 787                                 return true;
 788
 789                         if (!for_assembly) {
 790                                 if (action < SecurityAction.Demand || action > SecurityAction.InheritanceDemand) {
 791                                         Error_AttributeEmitError ("SecurityAction is out of range");
 792                                         return false;
 793                                 }
 794
 795                                 if ((action != SecurityAction.RequestMinimum && action != SecurityAction.RequestOptional && action != SecurityAction.RequestRefuse) && !for_assembly)
 796                                         return true;
 797                         }
 798
 799                         Error_AttributeEmitError (String.Concat ("SecurityAction '", action, "' is not valid for this declaration"));
 800                         return false;
 801                 }
 802
 803                 System.Security.Permissions.SecurityAction GetSecurityActionValue ()
 804                 {
 805                         return (SecurityAction)pos_values [0];
 806                 }
 807
 808                 /// <summary>
 809                 /// Creates instance of SecurityAttribute class and add result of CreatePermission method to permission table.
 810                 /// </summary>
 811                 /// <returns></returns>
 812                 public void ExtractSecurityPermissionSet (ListDictionary permissions)
 813                 {
 814                         if (TypeManager.LookupDeclSpace (Type) != null && RootContext.StdLib) {
 815                                 Error_AttributeEmitError ("security custom attributes can not be referenced from defining assembly");
 816                                 return;
 817                         }
 818
 819                         SecurityAttribute sa;
 820                         // For all assemblies except corlib we can avoid all hacks
 821                         if (RootContext.StdLib) {
 822                                 sa = (SecurityAttribute) Activator.CreateInstance (Type, pos_values);
 823
 824                                 if (prop_info_arr != null) {
 825                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 826                                                 PropertyInfo pi = prop_info_arr [i];
 827                                                 pi.SetValue (sa, prop_values_arr [i], null);
 828                                         }
 829                                 }
 830                         } else {
 831                                 Type temp_type = Type.GetType (Type.FullName);
 832                                 // HACK: All mscorlib attributes have same ctor syntax
 833                                 sa = (SecurityAttribute) Activator.CreateInstance (temp_type, new object[] { GetSecurityActionValue () } );
 834
 835                                 // All types are from newly created corlib but for invocation with old we need to convert them
 836                                 if (prop_info_arr != null) {
 837                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 838                                                 PropertyInfo emited_pi = prop_info_arr [i];
 839                                                 PropertyInfo pi = temp_type.GetProperty (emited_pi.Name, emited_pi.PropertyType);
 840
 841                                                 object old_instance = pi.PropertyType.IsEnum ?
 842                                                         System.Enum.ToObject (pi.PropertyType, prop_values_arr [i]) :
 843                                                         prop_values_arr [i];
 844
 845                                                 pi.SetValue (sa, old_instance, null);
 846                                         }
 847                                 }
 848                         }
 849
 850                         IPermission perm;
 851                         try {
 852                                 perm = sa.CreatePermission ();
 853                         }
 854                         catch (Exception e) {
 855                                 Error_AttributeEmitError (String.Format ("{0} was thrown during attribute processing: {1}", e.GetType (), e.Message));
 856                                 return;
 857                         }
 858                         SecurityAction action = GetSecurityActionValue ();
 859
 860                         // IS is correct because for corlib we are using an instance from old corlib
 861                         if (!(perm is System.Security.CodeAccessPermission)) {
 862                                 switch (action) {
 863                                         case SecurityAction.Demand:
 864                                                 action = (SecurityAction)13;
 865                                                 break;
 866                                         case SecurityAction.LinkDemand:
 867                                                 action = (SecurityAction)14;
 868                                                 break;
 869                                         case SecurityAction.InheritanceDemand:
 870                                                 action = (SecurityAction)15;
 871                                                 break;
 872                                 }
 873                         }
 874
 875                         PermissionSet ps = (PermissionSet)permissions [action];
 876                         if (ps == null) {
 877                                 if (sa is PermissionSetAttribute)
 878                                         ps = new PermissionSet (sa.Unrestricted ? PermissionState.Unrestricted : PermissionState.None);
 879                                 else
 880                                         ps = new PermissionSet (PermissionState.None);
 881
 882                                 permissions.Add (action, ps);
 883                         } else if (!ps.IsUnrestricted () && sa.Unrestricted) {
 884                                 ps = ps.Union (new PermissionSet (PermissionState.Unrestricted));
 885                                 permissions [action] = ps;
 886                         }
 887                         ps.AddPermission (perm);
 888                 }
 889
 890                 object GetValue (object value)
 891                 {
 892                         if (value is EnumConstant)
 893                                 return ((EnumConstant) value).GetValue ();
 894                         else
 895                                 return value;
 896                 }
 897
 898                 public object GetPositionalValue (int i)
 899                 {
 900                         return (pos_values == null) ? null : pos_values[i];
 901                 }
 902
 903                 object GetFieldValue (string name)
 904                 {
 905                         int i;
 906                         if (field_info_arr == null)
 907                                 return null;
 908                         i = 0;
 909                         foreach (FieldInfo fi in field_info_arr) {
 910                                 if (fi.Name == name)
 911                                         return GetValue (field_values_arr [i]);
 912                                 i++;
 913                         }
 914                         return null;
 915                 }
 916
 917                 public UnmanagedMarshal GetMarshal (Attributable attr)
 918                 {
 919                         object value = GetFieldValue ("SizeParamIndex");
 920                         if (value != null && UnmanagedType != UnmanagedType.LPArray) {
 921                                 Error_AttributeEmitError ("SizeParamIndex field is not valid for the specified unmanaged type");
 922                                 return null;
 923                         }
 924
 925                         object o = GetFieldValue ("ArraySubType");
 926                         UnmanagedType array_sub_type = o == null ? UnmanagedType.I4 : (UnmanagedType) o;
 927
 928                         switch (UnmanagedType) {
 929                         case UnmanagedType.CustomMarshaler:
 930                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
 931                                                                        BindingFlags.Static | BindingFlags.Public);
 932                                 if (define_custom == null) {
 933                                         Report.RuntimeMissingSupport (Location, "set marshal info");
 934                                         return null;
 935                                 }
 936
 937                                 object [] args = new object [4];
 938                                 args [0] = GetFieldValue ("MarshalTypeRef");
 939                                 args [1] = GetFieldValue ("MarshalCookie");
 940                                 args [2] = GetFieldValue ("MarshalType");
 941                                 args [3] = Guid.Empty;
 942                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
 943
 944                         case UnmanagedType.LPArray:
 945                                 return UnmanagedMarshal.DefineLPArray (array_sub_type);
 946
 947                         case UnmanagedType.SafeArray:
 948                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
 949
 950                         case UnmanagedType.ByValArray:
 951                                 FieldMember fm = attr as FieldMember;
 952                                 if (fm == null) {
 953                                         Error_AttributeEmitError ("Specified unmanaged type is only valid on fields");
 954                                         return null;
 955                                 }
 956                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
 957
 958                         case UnmanagedType.ByValTStr:
 959                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
 960
 961                         default:
 962                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
 963                         }
 964                 }
 965
 966                 public bool IsInternalCall
 967                 {
 968                         get { return ImplOptions == MethodImplOptions.InternalCall; }
 969                 }
 970
 971                 /// <summary>
 972                 /// Emit attribute for Attributable symbol
 973                 /// </summary>
 974                 public void Emit (EmitContext ec, Attributable ias, ListDictionary emitted_attr)
 975                 {
 976                         CustomAttributeBuilder cb = Resolve (ec);
 977                         if (cb == null)
 978                                 return;
 979
 980                         AttributeUsageAttribute usage_attr = GetAttributeUsage ();
 981                         if ((usage_attr.ValidOn & Target) == 0) {
 982                                 Report.Error (592, Location, "Attribute '{0}' is not valid on this declaration type. It is valid on {1} declarations only.", Name, GetValidTargets ());
 983                                 return;
 984                         }
 985
 986                         ias.ApplyAttributeBuilder (this, cb);
 987
 988                         if (!usage_attr.AllowMultiple) {
 989                                 ArrayList emitted_targets = (ArrayList)emitted_attr [Type];
 990                                 if (emitted_targets == null) {
 991                                         emitted_targets = new ArrayList ();
 992                                         emitted_attr.Add (Type, emitted_targets);
 993                                 } else if (emitted_targets.Contains (Target)) {
 994                                 Report.Error (579, Location, "Duplicate '" + Name + "' attribute");
 995                                         return;
 996                                 }
 997                                 emitted_targets.Add (Target);
 998                         }
 999
1000                         if (!RootContext.VerifyClsCompliance)
1001                                 return;
1002
1003                         // Here we are testing attribute arguments for array usage (error 3016)
1004                         if (ias.IsClsCompliaceRequired (ec.DeclSpace)) {
1005                                 if (Arguments == null)
1006                                         return;
1007
1008                                 ArrayList pos_args = (ArrayList) Arguments [0];
1009                                 if (pos_args != null) {
1010                                         foreach (Argument arg in pos_args) {
1011                                                 // Type is undefined (was error 246)
1012                                                 if (arg.Type == null)
1013                                                         return;
1014
1015                                                 if (arg.Type.IsArray) {
1016                                                         Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1017                                                         return;
1018                                                 }
1019                                         }
1020                                 }
1021
1022                                 if (Arguments.Count < 2)
1023                                         return;
1024
1025                                 ArrayList named_args = (ArrayList) Arguments [1];
1026                                 foreach (DictionaryEntry de in named_args) {
1027                                         Argument arg  = (Argument) de.Value;
1028
1029                                         // Type is undefined (was error 246)
1030                                         if (arg.Type == null)
1031                                                 return;
1032
1033                                         if (arg.Type.IsArray) {
1034                                                 Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1035                                                 return;
1036                                         }
1037                                 }
1038                         }
1039                 }
1040
1041                 public object GetValue (EmitContext ec, Constant c, Type target)
1042                 {
1043                         if (Convert.ImplicitConversionExists (ec, c, target))
1044                                 return c.GetValue ();
1045
1046                         Convert.Error_CannotImplicitConversion (Location, c.Type, target);
1047                         return null;
1048                 }
1049
1050                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,
1051                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
1052                 {
1053                         //
1054                         // We extract from the attribute the information we need
1055                         //
1056
1057                         if (Arguments == null) {
1058                                 Console.WriteLine ("Internal error : this is not supposed to happen !");
1059                                 return null;
1060                         }
1061
1062                         ResolveType (ec);
1063                         if (Type == null)
1064                                 return null;
1065
1066                         ArrayList named_args = new ArrayList ();
1067
1068                         ArrayList pos_args = (ArrayList) Arguments [0];
1069                         if (Arguments.Count > 1)
1070                                 named_args = (ArrayList) Arguments [1];
1071
1072
1073                         string dll_name = null;
1074
1075                         Argument tmp = (Argument) pos_args [0];
1076
1077                         if (!tmp.Resolve (ec, Location))
1078                                 return null;
1079
1080                         if (tmp.Expr is Constant)
1081                                 dll_name = (string) ((Constant) tmp.Expr).GetValue ();
1082                         else {
1083                                 Error_AttributeArgumentNotValid (Location);
1084                                 return null;
1085                         }
1086                         if (dll_name == null || dll_name == ""){
1087                                 Error_AttributeArgumentNotValid (": DllImport requires a non-empty string", Location);
1088                                 return null;
1089                         }
1090
1091                         // Now we process the named arguments
1092                         CallingConvention cc = CallingConvention.Winapi;
1093                         CharSet charset = CharSet.Ansi;
1094                         bool preserve_sig = true;
1095 #if FIXME
1096                         bool exact_spelling = false;
1097 #endif
1098                         bool set_last_err = false;
1099                         string entry_point = null;
1100
1101                         for (int i = 0; i < named_args.Count; i++) {
1102
1103                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
1104
1105                                 string member_name = (string) de.Key;
1106                                 Argument a  = (Argument) de.Value;
1107
1108                                 if (!a.Resolve (ec, Location))
1109                                         return null;
1110
1111                                 Expression member = Expression.MemberLookup (
1112                                         ec, Type, member_name,
1113                                         MemberTypes.Field | MemberTypes.Property,
1114                                         BindingFlags.Public | BindingFlags.Instance,
1115                                         Location);
1116
1117                                 if (member == null || !(member is FieldExpr)) {
1118                                         Error_InvalidNamedArgument (member_name);
1119                                         return null;
1120                                 }
1121
1122                                 if (member is FieldExpr) {
1123                                         FieldExpr fe = (FieldExpr) member;
1124                                         FieldInfo fi = fe.FieldInfo;
1125
1126                                         if (fi.IsInitOnly) {
1127                                                 Error_InvalidNamedArgument (member_name);
1128                                                 return null;
1129                                         }
1130
1131                                         if (a.Expr is Constant) {
1132                                                 Constant c = (Constant) a.Expr;
1133
1134                                                 try {
1135                                                         if (member_name == "CallingConvention"){
1136                                                                 object val = GetValue (ec, c, typeof (CallingConvention));
1137                                                                 if (val == null)
1138                                                                         return null;
1139                                                                 cc = (CallingConvention) val;
1140                                                         } else if (member_name == "CharSet"){
1141                                                                 charset = (CharSet) c.GetValue ();
1142                                                         } else if (member_name == "EntryPoint")
1143                                                                 entry_point = (string) c.GetValue ();
1144                                                         else if (member_name == "SetLastError")
1145                                                                 set_last_err = (bool) c.GetValue ();
1146 #if FIXME
1147                                                         else if (member_name == "ExactSpelling")
1148                                                                 exact_spelling = (bool) c.GetValue ();
1149 #endif
1150                                                         else if (member_name == "PreserveSig")
1151                                                                 preserve_sig = (bool) c.GetValue ();
1152                                                 } catch (InvalidCastException){
1153                                                         Error_InvalidNamedArgument (member_name);
1154                                                         Error_AttributeArgumentNotValid (Location);
1155                                                 }
1156                                         } else {
1157                                                 Error_AttributeArgumentNotValid (Location);
1158                                                 return null;
1159                                         }
1160
1161                                 }
1162                         }
1163
1164                         if (entry_point == null)
1165                                 entry_point = name;
1166                         if (set_last_err)
1167                                 charset = (CharSet)((int)charset | 0x40);
1168
1169                         MethodBuilder mb = builder.DefinePInvokeMethod (
1170                                 name, dll_name, entry_point, flags | MethodAttributes.HideBySig,
1171                                 CallingConventions.Standard,
1172                                 ret_type,
1173                                 param_types,
1174                                 cc,
1175                                 charset);
1176
1177                         if (preserve_sig)
1178                                 mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1179
1180                         return mb;
1181                 }
1182
1183                 private Expression GetValue ()
1184                 {
1185                         if ((Arguments == null) || (Arguments.Count < 1))
1186                                 return null;
1187                         ArrayList al = (ArrayList) Arguments [0];
1188                         if ((al == null) || (al.Count < 1))
1189                                 return null;
1190                         Argument arg = (Argument) al [0];
1191                         if ((arg == null) || (arg.Expr == null))
1192                                 return null;
1193                         return arg.Expr;
1194                 }
1195
1196                 public string GetString ()
1197                 {
1198                         Expression e = GetValue ();
1199                         if (e is StringLiteral)
1200                                 return (e as StringLiteral).Value;
1201                         return null;
1202                 }
1203
1204                 public bool GetBoolean ()
1205                 {
1206                         Expression e = GetValue ();
1207                         if (e is BoolLiteral)
1208                                 return (e as BoolLiteral).Value;
1209                         return false;
1210                 }
1211         }
1212
1213
1214         /// <summary>
1215         /// For global attributes (assembly, module) we need special handling.
1216         /// Attributes can be located in the several files
1217         /// </summary>
1218         public class GlobalAttribute: Attribute
1219         {
1220                 public readonly NamespaceEntry ns;
1221
1222                 public GlobalAttribute (TypeContainer container, string target,
1223                                         Expression left_expr, string identifier, ArrayList args, Location loc):
1224                         base (target, left_expr, identifier, args, loc)
1225                 {
1226                         ns = container.NamespaceEntry;
1227                 }
1228
1229                 void Enter ()
1230                 {
1231                         // RootContext.Tree.Types has a single NamespaceEntry which gets overwritten
1232                         // each time a new file is parsed.  However, we need to use the NamespaceEntry
1233                         // in effect where the attribute was used.  Since code elsewhere cannot assume
1234                         // that the NamespaceEntry is right, just overwrite it.
1235                         //
1236                         // Precondition: RootContext.Tree.Types == null
1237
1238                         if (RootContext.Tree.Types.NamespaceEntry != null)
1239                                 throw new InternalErrorException (Location + " non-null NamespaceEntry");
1240
1241                         RootContext.Tree.Types.NamespaceEntry = ns;
1242                 }
1243
1244                 void Leave ()
1245                 {
1246                         RootContext.Tree.Types.NamespaceEntry = null;
1247                 }
1248
1249                 public override Type ResolveType (EmitContext ec)
1250                 {
1251                         Enter ();
1252                         Type retval = base.ResolveType (ec);
1253                         Leave ();
1254                         return retval;
1255                 }
1256
1257                 public override CustomAttributeBuilder Resolve (EmitContext ec)
1258                 {
1259                         Enter ();
1260                         CustomAttributeBuilder retval = base.Resolve (ec);
1261                         Leave ();
1262                         return retval;
1263                 }
1264         }
1265
1266         public class Attributes {
1267                 public ArrayList Attrs;
1268
1269                 public Attributes (Attribute a)
1270                 {
1271                         Attrs = new ArrayList ();
1272                         Attrs.Add (a);
1273                 }
1274
1275                 public Attributes (ArrayList attrs)
1276                 {
1277                         Attrs = attrs;
1278                 }
1279
1280                 public void AddAttributes (ArrayList attrs)
1281                 {
1282                         Attrs.AddRange (attrs);
1283                 }
1284
1285                 /// <summary>
1286                 /// Checks whether attribute target is valid for the current element
1287                 /// </summary>
1288                 public bool CheckTargets (Attributable member)
1289                 {
1290                         string[] valid_targets = member.ValidAttributeTargets;
1291                         foreach (Attribute a in Attrs) {
1292                                 if (a.ExplicitTarget == null || a.ExplicitTarget == valid_targets [0]) {
1293                                         a.Target = member.AttributeTargets;
1294                                         continue;
1295                                 }
1296
1297                                 // TODO: we can skip the first item
1298                                 if (((IList) valid_targets).Contains (a.ExplicitTarget)) {
1299                                         switch (a.ExplicitTarget) {
1300                                                 case "return": a.Target = AttributeTargets.ReturnValue; continue;
1301                                                 case "param": a.Target = AttributeTargets.Parameter; continue;
1302                                                 case "field": a.Target = AttributeTargets.Field; continue;
1303                                                 case "method": a.Target = AttributeTargets.Method; continue;
1304                                                 case "property": a.Target = AttributeTargets.Property; continue;
1305                                         }
1306                                         throw new InternalErrorException ("Unknown explicit target: " + a.ExplicitTarget);
1307                                 }
1308
1309                                 StringBuilder sb = new StringBuilder ();
1310                                 foreach (string s in valid_targets) {
1311                                         sb.Append (s);
1312                                         sb.Append (", ");
1313                                 }
1314                                 sb.Remove (sb.Length - 2, 2);
1315                                 Report.Error (657, a.Location, "'{0}' is not a valid attribute location for this declaration. Valid attribute locations for this declaration are '{1}'", a.ExplicitTarget, sb.ToString ());
1316                                 return false;
1317                         }
1318                         return true;
1319                 }
1320
1321                 public Attribute Search (Type t, EmitContext ec)
1322                 {
1323                         foreach (Attribute a in Attrs) {
1324                                 if (a.ResolveType (ec) == t)
1325                                         return a;
1326                         }
1327                         return null;
1328                 }
1329
1330                 /// <summary>
1331                 /// Returns all attributes of type 't'. Use it when attribute is AllowMultiple = true
1332                 /// </summary>
1333                 public Attribute[] SearchMulti (Type t, EmitContext ec)
1334                 {
1335                         ArrayList ar = null;
1336
1337                         foreach (Attribute a in Attrs) {
1338                                 if (a.ResolveType (ec) == t) {
1339                                         if (ar == null)
1340                                                 ar = new ArrayList ();
1341                                         ar.Add (a);
1342                                 }
1343                         }
1344
1345                         return ar == null ? null : ar.ToArray (typeof (Attribute)) as Attribute[];
1346                 }
1347
1348                 public void Emit (EmitContext ec, Attributable ias)
1349                 {
1350                         if (!CheckTargets (ias))
1351                                 return;
1352
1353                         ListDictionary ld = new ListDictionary ();
1354
1355                         foreach (Attribute a in Attrs)
1356                                 a.Emit (ec, ias, ld);
1357                 }
1358
1359                 public bool Contains (Type t, EmitContext ec)
1360                 {
1361                         return Search (t, ec) != null;
1362                 }
1363         }
1364
1365         /// <summary>
1366         /// Helper class for attribute verification routine.
1367         /// </summary>
1368         sealed class AttributeTester
1369         {
1370                 static PtrHashtable analyzed_types = new PtrHashtable ();
1371                 static PtrHashtable analyzed_types_obsolete = new PtrHashtable ();
1372                 static PtrHashtable analyzed_member_obsolete = new PtrHashtable ();
1373                 static PtrHashtable analyzed_method_excluded = new PtrHashtable ();
1374                 static PtrHashtable fixed_buffer_cache = new PtrHashtable ();
1375
1376                 static object TRUE = new object ();
1377                 static object FALSE = new object ();
1378
1379                 private AttributeTester ()
1380                 {
1381                 }
1382
1383                 /// <summary>
1384                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1385                 /// It tests differing only in ref or out, or in array rank.
1386                 /// </summary>
1387                 public static bool AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1388                 {
1389                         if (types_a == null || types_b == null)
1390                                 return true;
1391
1392                         if (types_a.Length != types_b.Length)
1393                                 return true;
1394
1395                         for (int i = 0; i < types_b.Length; ++i) {
1396                                 Type aType = types_a [i];
1397                                 Type bType = types_b [i];
1398
1399                                 if (aType.IsArray && bType.IsArray && aType.GetArrayRank () != bType.GetArrayRank () && aType.GetElementType () == bType.GetElementType ()) {
1400                                         return false;
1401                                 }
1402
1403                                 Type aBaseType = aType;
1404                                 bool is_either_ref_or_out = false;
1405
1406                                 if (aType.IsByRef || aType.IsPointer) {
1407                                         aBaseType = aType.GetElementType ();
1408                                         is_either_ref_or_out = true;
1409                                 }
1410
1411                                 Type bBaseType = bType;
1412                                 if (bType.IsByRef || bType.IsPointer)
1413                                 {
1414                                         bBaseType = bType.GetElementType ();
1415                                         is_either_ref_or_out = !is_either_ref_or_out;
1416                                 }
1417
1418                                 if (aBaseType != bBaseType)
1419                                         continue;
1420
1421                                 if (is_either_ref_or_out)
1422                                         return false;
1423                         }
1424                         return true;
1425                 }
1426
1427                 /// <summary>
1428                 /// Goes through all parameters and test if they are CLS-Compliant.
1429                 /// </summary>
1430                 public static bool AreParametersCompliant (Parameter[] fixedParameters, Location loc)
1431                 {
1432                         if (fixedParameters == null)
1433                                 return true;
1434
1435                         foreach (Parameter arg in fixedParameters) {
1436                                 if (!AttributeTester.IsClsCompliant (arg.ParameterType)) {
1437                                         Report.Error (3001, loc, "Argument type '{0}' is not CLS-compliant", arg.GetSignatureForError ());
1438                                         return false;
1439                                 }
1440                         }
1441                         return true;
1442                 }
1443
1444
1445                 /// <summary>
1446                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1447                 /// </summary>
1448                 public static bool IsClsCompliant (Type type)
1449                 {
1450                         if (type == null)
1451                                 return true;
1452
1453                         object type_compliance = analyzed_types[type];
1454                         if (type_compliance != null)
1455                                 return type_compliance == TRUE;
1456
1457                         if (type.IsPointer) {
1458                                 analyzed_types.Add (type, null);
1459                                 return false;
1460                         }
1461
1462                         bool result;
1463                         if (type.IsArray || type.IsByRef)       {
1464                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1465                         } else {
1466                                 result = AnalyzeTypeCompliance (type);
1467                         }
1468                         analyzed_types.Add (type, result ? TRUE : FALSE);
1469                         return result;
1470                 }
1471
1472                 /// <summary>
1473                 /// Returns IFixedBuffer implementation if field is fixed buffer else null.
1474                 /// </summary>
1475                 public static IFixedBuffer GetFixedBuffer (FieldInfo fi)
1476                 {
1477                         FieldBase fb = TypeManager.GetField (fi);
1478                         if (fb != null) {
1479                                 return fb as IFixedBuffer;
1480                         }
1481
1482 #if NET_2_0
1483                         object o = fixed_buffer_cache [fi];
1484                         if (o == null) {
1485                                 if (System.Attribute.GetCustomAttribute (fi, TypeManager.fixed_buffer_attr_type) == null) {
1486                                         fixed_buffer_cache.Add (fi, FALSE);
1487                                         return null;
1488                                 }
1489
1490                                 IFixedBuffer iff = new FixedFieldExternal (fi);
1491                                 fixed_buffer_cache.Add (fi, iff);
1492                                 return iff;
1493                         }
1494
1495                         if (o == FALSE)
1496                                 return null;
1497
1498                         return (IFixedBuffer)o;
1499 #else
1500                         return null;
1501 #endif
1502                 }
1503
1504                 public static void VerifyModulesClsCompliance ()
1505                 {
1506                         Module[] modules = TypeManager.Modules;
1507                         if (modules == null)
1508                                 return;
1509
1510                         // The first module is generated assembly
1511                         for (int i = 1; i < modules.Length; ++i) {
1512                                 Module module = modules [i];
1513                                 if (!IsClsCompliant (module)) {
1514                                         Report.Error (3013, "Added modules must be marked with the CLSCompliant attribute to match the assembly", module.Name);
1515                                         return;
1516                                 }
1517                         }
1518                 }
1519
1520                 /// <summary>
1521                 /// Tests container name for CLS-Compliant name (differing only in case)
1522                 /// </summary>
1523                 public static void VerifyTopLevelNameClsCompliance ()
1524                 {
1525                         Hashtable locase_table = new Hashtable ();
1526
1527                         // Convert imported type names to lower case and ignore not cls compliant
1528                         foreach (DictionaryEntry de in TypeManager.all_imported_types) {
1529                                 Type t = (Type)de.Value;
1530                                 if (!AttributeTester.IsClsCompliant (t))
1531                                         continue;
1532
1533                                 locase_table.Add (((string)de.Key).ToLower (System.Globalization.CultureInfo.InvariantCulture), t);
1534                         }
1535
1536                         foreach (DictionaryEntry de in RootContext.Tree.Decls) {
1537                                 DeclSpace decl = (DeclSpace)de.Value;
1538                                 if (!decl.IsClsCompliaceRequired (decl))
1539                                         continue;
1540
1541                                 string lcase = decl.Name.ToLower (System.Globalization.CultureInfo.InvariantCulture);
1542                                 if (!locase_table.Contains (lcase)) {
1543                                         locase_table.Add (lcase, decl);
1544                                         continue;
1545                                 }
1546
1547                                 object conflict = locase_table [lcase];
1548                                 if (conflict is Type)
1549                                         Report.SymbolRelatedToPreviousError ((Type)conflict);
1550                                 else
1551                                         Report.SymbolRelatedToPreviousError ((MemberCore)conflict);
1552
1553                                 Report.Error (3005, decl.Location, "Identifier '{0}' differing only in case is not CLS-compliant", decl.GetSignatureForError ());
1554                         }
1555                 }
1556
1557                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1558                 {
1559                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1560                         if (CompliantAttribute.Length == 0)
1561                                 return false;
1562
1563                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1564                 }
1565
1566                 static bool AnalyzeTypeCompliance (Type type)
1567                 {
1568                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1569                         if (ds != null) {
1570                                 return ds.IsClsCompliaceRequired (ds.Parent);
1571                         }
1572
1573                         if (type.IsGenericParameter || type.IsGenericInstance)
1574                                 return false;
1575
1576                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1577                         if (CompliantAttribute.Length == 0)
1578                                 return IsClsCompliant (type.Assembly);
1579
1580                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1581                 }
1582
1583                 /// <summary>
1584                 /// Returns instance of ObsoleteAttribute when type is obsolete
1585                 /// </summary>
1586                 public static ObsoleteAttribute GetObsoleteAttribute (Type type)
1587                 {
1588                         object type_obsolete = analyzed_types_obsolete [type];
1589                         if (type_obsolete == FALSE)
1590                                 return null;
1591
1592                         if (type_obsolete != null)
1593                                 return (ObsoleteAttribute)type_obsolete;
1594
1595                         ObsoleteAttribute result = null;
1596                         if (type.IsByRef || type.IsArray || type.IsPointer) {
1597                                 result = GetObsoleteAttribute (TypeManager.GetElementType (type));
1598                         } else if (type.IsGenericParameter || type.IsGenericInstance)
1599                                 return null;
1600                         else {
1601                                 DeclSpace type_ds = TypeManager.LookupDeclSpace (type);
1602
1603                                 // Type is external, we can get attribute directly
1604                                 if (type_ds == null) {
1605                                         object[] attribute = type.GetCustomAttributes (TypeManager.obsolete_attribute_type, false);
1606                                         if (attribute.Length == 1)
1607                                                 result = (ObsoleteAttribute)attribute [0];
1608                                 } else {
1609                                         result = type_ds.GetObsoleteAttribute (type_ds);
1610                                 }
1611                         }
1612
1613                         analyzed_types_obsolete.Add (type, result == null ? FALSE : result);
1614                         return result;
1615                 }
1616
1617                 /// <summary>
1618                 /// Returns instance of ObsoleteAttribute when method is obsolete
1619                 /// </summary>
1620                 public static ObsoleteAttribute GetMethodObsoleteAttribute (MethodBase mb)
1621                 {
1622                         IMethodData mc = TypeManager.GetMethod (mb);
1623                         if (mc != null)
1624                                 return mc.GetObsoleteAttribute ();
1625
1626                         // compiler generated methods are not registered by AddMethod
1627                         if (mb.DeclaringType is TypeBuilder)
1628                                 return null;
1629
1630                         PropertyInfo pi = PropertyExpr.AccessorTable [mb] as PropertyInfo;
1631                         if (pi != null)
1632                                 return GetMemberObsoleteAttribute (pi);
1633
1634                         return GetMemberObsoleteAttribute (mb);
1635                 }
1636
1637                 /// <summary>
1638                 /// Returns instance of ObsoleteAttribute when member is obsolete
1639                 /// </summary>
1640                 public static ObsoleteAttribute GetMemberObsoleteAttribute (MemberInfo mi)
1641                 {
1642                         object type_obsolete = analyzed_member_obsolete [mi];
1643                         if (type_obsolete == FALSE)
1644                                 return null;
1645
1646                         if (type_obsolete != null)
1647                                 return (ObsoleteAttribute)type_obsolete;
1648
1649                         if ((mi.DeclaringType is TypeBuilder) || mi.DeclaringType.IsGenericInstance)
1650                                 return null;
1651
1652                         ObsoleteAttribute oa = System.Attribute.GetCustomAttribute (mi, TypeManager.obsolete_attribute_type, false) as ObsoleteAttribute;
1653                         analyzed_member_obsolete.Add (mi, oa == null ? FALSE : oa);
1654                         return oa;
1655                 }
1656
1657                 /// <summary>
1658                 /// Common method for Obsolete error/warning reporting.
1659                 /// </summary>
1660                 public static void Report_ObsoleteMessage (ObsoleteAttribute oa, string member, Location loc)
1661                 {
1662                         if (oa.IsError) {
1663                                 Report.Error (619, loc, "'{0}' is obsolete: '{1}'", member, oa.Message);
1664                                 return;
1665                         }
1666
1667                         if (oa.Message == null) {
1668                                 Report.Warning (612, loc, "'{0}' is obsolete", member);
1669                                 return;
1670                         }
1671                         if (RootContext.WarningLevel >= 2)
1672                                 Report.Warning (618, loc, "'{0}' is obsolete: '{1}'", member, oa.Message);
1673                 }
1674
1675                 public static bool IsConditionalMethodExcluded (MethodBase mb)
1676                 {
1677                         object excluded = analyzed_method_excluded [mb];
1678                         if (excluded != null)
1679                                 return excluded == TRUE ? true : false;
1680
1681                         if (mb.Mono_IsInflatedMethod)
1682                                 return false;
1683
1684                         ConditionalAttribute[] attrs = mb.GetCustomAttributes (TypeManager.conditional_attribute_type, true) as ConditionalAttribute[];
1685                         if (attrs.Length == 0) {
1686                                 analyzed_method_excluded.Add (mb, FALSE);
1687                                 return false;
1688                         }
1689
1690                         foreach (ConditionalAttribute a in attrs) {
1691                                 if (RootContext.AllDefines.Contains (a.ConditionString)) {
1692                                         analyzed_method_excluded.Add (mb, FALSE);
1693                                         return false;
1694                                 }
1695                         }
1696                         analyzed_method_excluded.Add (mb, TRUE);
1697                         return true;
1698                 }
1699         }
1700 }