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 ArrayList Arguments;
  76
  77                 public readonly Location Location;
  78
  79                 public Type Type;
  80
  81                 bool resolve_error;
  82
  83                 // Is non-null if type is AttributeUsageAttribute
  84                 AttributeUsageAttribute usage_attribute;
  85
  86                 public AttributeUsageAttribute UsageAttribute {
  87                         get {
  88                                 return usage_attribute;
  89                         }
  90                 }
  91
  92                 MethodImplOptions ImplOptions;
  93                 UnmanagedType     UnmanagedType;
  94                 CustomAttributeBuilder cb;
  95
  96                 // non-null if named args present after Resolve () is called
  97                 PropertyInfo [] prop_info_arr;
  98                 FieldInfo [] field_info_arr;
  99                 object [] field_values_arr;
 100                 object [] prop_values_arr;
 101                 object [] pos_values;
 102
 103                 static PtrHashtable usage_attr_cache = new PtrHashtable ();
 104
 105                 public Attribute (string target, string name, ArrayList args, Location loc)
 106                 {
 107                         Name = name;
 108                         Arguments = args;
 109                         Location = loc;
 110                         ExplicitTarget = target;
 111                 }
 112
 113                 void Error_InvalidNamedArgument (string name)
 114                 {
 115                         Report.Error (617, Location, "Invalid attribute argument: '{0}'.  Argument must be fields " +
 116                                       "fields which are not readonly, static or const;  or read-write instance properties.",
 117                                       Name);
 118                 }
 119
 120                 static void Error_AttributeArgumentNotValid (string extra, Location loc)
 121                 {
 122                         Report.Error (182, loc,
 123                                       "An attribute argument must be a constant expression, typeof " +
 124                                       "expression or array creation expression" + extra);
 125                 }
 126
 127                 static void Error_AttributeArgumentNotValid (Location loc)
 128                 {
 129                         Error_AttributeArgumentNotValid ("", loc);
 130                 }
 131
 132                 static void Error_TypeParameterInAttribute (Location loc)
 133                 {
 134                         Report.Error (
 135                                 -202, loc, "Can not use a type parameter in an attribute");
 136                 }
 137
 138                 /// <summary>
 139                 /// This is rather hack. We report many emit attribute error with same error to be compatible with
 140                 /// csc. But because csc has to report them this way because error came from ilasm we needn't.
 141                 /// </summary>
 142                 public void Error_AttributeEmitError (string inner)
 143                 {
 144                         Report.Error (647, Location, "Error emitting '{0}' attribute because '{1}'", Name, inner);
 145                 }
 146
 147                 public void Error_InvalidSecurityParent ()
 148                 {
 149                         Error_AttributeEmitError ("it is attached to invalid parent");
 150                 }
 151
 152                 void Error_AttributeConstructorMismatch ()
 153                 {
 154                         Report.Error (-6, Location,
 155                                       "Could not find a constructor for this argument list.");
 156                 }
 157
 158                 /// <summary>
 159                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 160                 /// </summary>
 161                 protected virtual Type CheckAttributeType (EmitContext ec)
 162                 {
 163                         string NameAttribute = Name + "Attribute";
 164                         FullNamedExpression n1 = ec.ResolvingTypeTree
 165                                 ? ec.DeclSpace.FindType (Location, Name)
 166                                 : ec.DeclSpace.LookupType (Name, true, Location);
 167
 168                         // FIXME: Shouldn't do this for quoted attributes: [@A]
 169                         FullNamedExpression n2 = ec.ResolvingTypeTree
 170                                 ? ec.DeclSpace.FindType (Location, NameAttribute)
 171                                 : ec.DeclSpace.LookupType (NameAttribute, true, Location);
 172
 173                         TypeExpr e1 = n1 == null ? null : n1 as TypeExpr;
 174                         TypeExpr e2 = n2 == null ? null : n2 as TypeExpr;
 175
 176                         Type t1 = e1 == null ? null : e1.ResolveType (ec);
 177                         Type t2 = e2 == null ? null : e2.ResolveType (ec);
 178
 179                         String err0616 = null;
 180                         if (t1 != null && ! t1.IsSubclassOf (TypeManager.attribute_type)) {
 181                                 t1 = null;
 182                                 err0616 = "'" + Name + "': is not an attribute class";
 183                         }
 184                         if (t2 != null && ! t2.IsSubclassOf (TypeManager.attribute_type)) {
 185                                 t2 = null;
 186                                 err0616 = (err0616 != null)
 187                                         ? "Neither '" + Name + "' nor '" + NameAttribute +"' is an attribute class"
 188                                         : "'" + Name + "Attribute': is not an attribute class";
 189                         }
 190
 191                         if (t1 != null && t2 != null) {
 192                                 Report.Error(1614, Location, "'" + Name + "': is ambiguous; "
 193                                              + " use either '@" + Name + "' or '" + NameAttribute + "'");
 194                                 return null;
 195                         }
 196                         if (t1 != null)
 197                                 return t1;
 198                         if (t2 != null)
 199                                 return t2;
 200                         if (err0616 != null) {
 201                                 Report.Error (616, Location, err0616);
 202                                 return null;
 203                         }
 204
 205                         Report.Error (246, Location,
 206                                       "Could not find attribute '" + Name
 207                                       + "' (are you missing a using directive or an assembly reference ?)");
 208
 209                         resolve_error = true;
 210                         return null;
 211                 }
 212
 213                 public Type ResolveType (EmitContext ec)
 214                 {
 215                         if (Type == null)
 216                                 Type = CheckAttributeType (ec);
 217                         return Type;
 218                 }
 219
 220                 /// <summary>
 221                 ///   Validates the guid string
 222                 /// </summary>
 223                 bool ValidateGuid (string guid)
 224                 {
 225                         try {
 226                                 new Guid (guid);
 227                                 return true;
 228                         } catch {
 229                                 Report.Error (647, Location, "Format of GUID is invalid: " + guid);
 230                                 return false;
 231                         }
 232                 }
 233
 234                 string GetFullMemberName (string member)
 235                 {
 236                         return Type.FullName + '.' + member;
 237                 }
 238
 239                 //
 240                 // Given an expression, if the expression is a valid attribute-argument-expression
 241                 // returns an object that can be used to encode it, or null on failure.
 242                 //
 243                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, Type arg_type, out object result)
 244                 {
 245                         if (e is EnumConstant) {
 246                                 if (RootContext.StdLib)
 247                                         result = ((EnumConstant)e).GetValueAsEnumType ();
 248                                 else
 249                                         result = ((EnumConstant)e).GetValue ();
 250
 251                                 return true;
 252                         }
 253
 254                         Constant constant = e as Constant;
 255                         if (constant != null) {
 256                                 if (e.Type != arg_type) {
 257                                         constant = Const.ChangeType (loc, constant, arg_type);
 258                                         if (constant == null) {
 259                                                 result = null;
 260                                                 Error_AttributeArgumentNotValid (loc);
 261                                                 return false;
 262                                         }
 263                                 }
 264                                 result = constant.GetValue ();
 265                                 return true;
 266                         } else if (e is TypeOf) {
 267                                 result = ((TypeOf) e).TypeArg;
 268                                 return true;
 269                         } else if (e is ArrayCreation){
 270                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();
 271                                 if (result != null)
 272                                         return true;
 273                         } else if (e is EmptyCast) {
 274                                 Expression child = ((EmptyCast)e).Child;
 275                                 return GetAttributeArgumentExpression (child, loc, child.Type, out result);
 276                         }
 277
 278                         result = null;
 279                         Error_AttributeArgumentNotValid (loc);
 280                         return false;
 281                 }
 282
 283                 public virtual CustomAttributeBuilder Resolve (EmitContext ec)
 284                 {
 285                         if (resolve_error)
 286                                 return null;
 287
 288                         resolve_error = true;
 289
 290                         Type oldType = Type;
 291
 292                         // Sanity check.
 293                         Type = CheckAttributeType (ec);
 294
 295                         if (oldType == null && Type == null)
 296                                 return null;
 297                         if (oldType != null && oldType != Type){
 298                                 Report.Error (-27, Location,
 299                                               "Attribute {0} resolved to different types at different times: {1} vs. {2}",
 300                                               Name, oldType, Type);
 301                                 return null;
 302                         }
 303
 304                         if (Type.IsAbstract) {
 305                                 Report.Error (653, Location, "Cannot apply attribute class '{0}' because it is abstract", Name);
 306                                 return null;
 307                         }
 308
 309                         bool MethodImplAttr = false;
 310                         bool MarshalAsAttr = false;
 311                         bool GuidAttr = false;
 312                         bool usage_attr = false;
 313
 314                         bool DoCompares = true;
 315
 316                         //
 317                         // If we are a certain special attribute, we
 318                         // set the information accordingly
 319                         //
 320
 321                         if (Type == TypeManager.attribute_usage_type)
 322                                 usage_attr = true;
 323                         else if (Type == TypeManager.methodimpl_attr_type)
 324                                 MethodImplAttr = true;
 325                         else if (Type == TypeManager.marshal_as_attr_type)
 326                                 MarshalAsAttr = true;
 327                         else if (Type == TypeManager.guid_attr_type)
 328                                 GuidAttr = true;
 329                         else
 330                                 DoCompares = false;
 331
 332                         // Now we extract the positional and named arguments
 333
 334                         ArrayList pos_args = new ArrayList ();
 335                         ArrayList named_args = new ArrayList ();
 336                         int pos_arg_count = 0;
 337
 338                         if (Arguments != null) {
 339                                 pos_args = (ArrayList) Arguments [0];
 340                                 if (pos_args != null)
 341                                         pos_arg_count = pos_args.Count;
 342                                 if (Arguments.Count > 1)
 343                                         named_args = (ArrayList) Arguments [1];
 344                         }
 345
 346                         pos_values = new object [pos_arg_count];
 347
 348                         //
 349                         // First process positional arguments
 350                         //
 351
 352                         int i;
 353                         for (i = 0; i < pos_arg_count; i++) {
 354                                 Argument a = (Argument) pos_args [i];
 355                                 Expression e;
 356
 357                                 if (!a.Resolve (ec, Location))
 358                                         return null;
 359
 360                                 e = a.Expr;
 361
 362                                 object val;
 363                                 if (!GetAttributeArgumentExpression (e, Location, a.Type, out val))
 364                                         return null;
 365
 366                                 pos_values [i] = val;
 367
 368                                 if (DoCompares){
 369                                         if (usage_attr) {
 370                                                 if ((int)val == 0) {
 371                                                         Report.Error (591, Location, "Invalid value for argument to 'System.AttributeUsage' attribute");
 372                                                         return null;
 373                                                 }
 374                                                 usage_attribute = new AttributeUsageAttribute ((AttributeTargets)val);
 375                                         } else if (MethodImplAttr) {
 376                                                 this.ImplOptions = (MethodImplOptions) val;
 377                                         } else if (GuidAttr){
 378                                                 //
 379                                                 // we will later check the validity of the type
 380                                                 //
 381                                                 if (val is string){
 382                                                         if (!ValidateGuid ((string) val))
 383                                                                 return null;
 384                                                 }
 385
 386                                         } else if (MarshalAsAttr)
 387                                                 this.UnmanagedType =
 388                                                 (System.Runtime.InteropServices.UnmanagedType) val;
 389                                 }
 390                         }
 391
 392                         //
 393                         // Now process named arguments
 394                         //
 395
 396                         ArrayList field_infos = null;
 397                         ArrayList prop_infos  = null;
 398                         ArrayList field_values = null;
 399                         ArrayList prop_values = null;
 400
 401                         if (named_args.Count > 0) {
 402                                 field_infos = new ArrayList ();
 403                                 prop_infos  = new ArrayList ();
 404                                 field_values = new ArrayList ();
 405                                 prop_values = new ArrayList ();
 406                         }
 407
 408                         Hashtable seen_names = new Hashtable();
 409
 410                         for (i = 0; i < named_args.Count; i++) {
 411                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 412                                 string member_name = (string) de.Key;
 413                                 Argument a  = (Argument) de.Value;
 414                                 Expression e;
 415
 416                                 if (seen_names.Contains(member_name)) {
 417                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 418                                         return null;
 419                                 }
 420                                 seen_names.Add(member_name, 1);
 421
 422                                 if (!a.Resolve (ec, Location))
 423                                         return null;
 424
 425                                 Expression member = Expression.MemberLookup (
 426                                         ec, Type, member_name,
 427                                         MemberTypes.Field | MemberTypes.Property,
 428                                         BindingFlags.Public | BindingFlags.Instance,
 429                                         Location);
 430
 431                                 if (member == null) {
 432                                         member = Expression.MemberLookup (ec, Type, member_name,
 433                                                 MemberTypes.Field | MemberTypes.Property, BindingFlags.NonPublic | BindingFlags.Instance,
 434                                                 Location);
 435
 436                                         if (member != null) {
 437                                                 Report.Error (122, Location, "'{0}' is inaccessible due to its protection level", GetFullMemberName (member_name));
 438                                                 return null;
 439                                         }
 440                                 }
 441
 442                                 if (member == null){
 443                                         Report.Error (117, Location, "Attribute `{0}' does not contain a definition for `{1}'",
 444                                                       Type, member_name);
 445                                         return null;
 446                                 }
 447
 448                                 if (!(member is PropertyExpr || member is FieldExpr)) {
 449                                         Error_InvalidNamedArgument (member_name);
 450                                         return null;
 451                                 }
 452
 453                                 e = a.Expr;
 454                                 if (e is TypeParameterExpr){
 455                                         Error_TypeParameterInAttribute (Location);
 456                                         return null;
 457                                 }
 458
 459                                 if (member is PropertyExpr) {
 460                                         PropertyExpr pe = (PropertyExpr) member;
 461                                         PropertyInfo pi = pe.PropertyInfo;
 462
 463                                         if (!pi.CanWrite || !pi.CanRead) {
 464                                                 Report.SymbolRelatedToPreviousError (pi);
 465                                                 Error_InvalidNamedArgument (member_name);
 466                                                 return null;
 467                                         }
 468
 469                                         object value;
 470                                         if (!GetAttributeArgumentExpression (e, Location, pi.PropertyType, out value))
 471                                                                 return null;
 472
 473                                                 if (usage_attribute != null) {
 474                                                         if (member_name == "AllowMultiple")
 475                                                         usage_attribute.AllowMultiple = (bool) value;
 476                                                         if (member_name == "Inherited")
 477                                                         usage_attribute.Inherited = (bool) value;
 478                                         }
 479
 480                                         prop_values.Add (value);
 481                                         prop_infos.Add (pi);
 482
 483                                 } else if (member is FieldExpr) {
 484                                         FieldExpr fe = (FieldExpr) member;
 485                                         FieldInfo fi = fe.FieldInfo;
 486
 487                                         if (fi.IsInitOnly) {
 488                                                 Error_InvalidNamedArgument (member_name);
 489                                                 return null;
 490                                         }
 491
 492                                         object value;
 493                                         if (!GetAttributeArgumentExpression (e, Location, fi.FieldType, out value))
 494                                                 return null;
 495
 496                                         field_values.Add (value);
 497
 498                                         field_infos.Add (fi);
 499                                 }
 500                         }
 501
 502                         Expression mg = Expression.MemberLookup (
 503                                 ec, Type, ".ctor", MemberTypes.Constructor,
 504                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 505                                 Location);
 506
 507                         if (mg == null) {
 508                                 Error_AttributeConstructorMismatch ();
 509                                 return null;
 510                         }
 511
 512                         MethodBase constructor = Invocation.OverloadResolve (
 513                                 ec, (MethodGroupExpr) mg, pos_args, false, Location);
 514
 515                         if (constructor == null) {
 516                                 return null;
 517                         }
 518
 519                         //
 520                         // Now we perform some checks on the positional args as they
 521                         // cannot be null for a constructor which expects a parameter
 522                         // of type object
 523                         //
 524
 525                         ParameterData pd = Invocation.GetParameterData (constructor);
 526
 527                         int last_real_param = pd.Count;
 528                         if (pd.HasParams) {
 529                                 // When the params is not filled we need to put one
 530                                 if (last_real_param > pos_arg_count) {
 531                                         object [] new_pos_values = new object [pos_arg_count + 1];
 532                                         pos_values.CopyTo (new_pos_values, 0);
 533                                         new_pos_values [pos_arg_count] = new object [] {} ;
 534                                         pos_values = new_pos_values;
 535                                 }
 536                                 last_real_param--;
 537                         }
 538
 539                         for (int j = 0; j < pos_arg_count; ++j) {
 540                                 Argument a = (Argument) pos_args [j];
 541
 542                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {
 543                                         Error_AttributeArgumentNotValid (Location);
 544                                         return null;
 545                                 }
 546
 547                                 if (j < last_real_param)
 548                                         continue;
 549
 550                                 if (j == last_real_param) {
 551                                         object [] array = new object [pos_arg_count - last_real_param];
 552                                         array [0] = pos_values [j];
 553                                         pos_values [j] = array;
 554                                         continue;
 555                                 }
 556
 557                                 object [] params_array = (object []) pos_values [last_real_param];
 558                                 params_array [j - last_real_param] = pos_values [j];
 559                         }
 560
 561                         // Adjust the size of the pos_values if it had params
 562                         if (last_real_param != pos_arg_count) {
 563                                 object [] new_pos_values = new object [last_real_param + 1];
 564                                 Array.Copy (pos_values, new_pos_values, last_real_param + 1);
 565                                 pos_values = new_pos_values;
 566                         }
 567
 568                         try {
 569                                 if (named_args.Count > 0) {
 570                                         prop_info_arr = new PropertyInfo [prop_infos.Count];
 571                                         field_info_arr = new FieldInfo [field_infos.Count];
 572                                         field_values_arr = new object [field_values.Count];
 573                                         prop_values_arr = new object [prop_values.Count];
 574
 575                                         field_infos.CopyTo  (field_info_arr, 0);
 576                                         field_values.CopyTo (field_values_arr, 0);
 577
 578                                         prop_values.CopyTo  (prop_values_arr, 0);
 579                                         prop_infos.CopyTo   (prop_info_arr, 0);
 580
 581                                         cb = new CustomAttributeBuilder (
 582                                                 (ConstructorInfo) constructor, pos_values,
 583                                                 prop_info_arr, prop_values_arr,
 584                                                 field_info_arr, field_values_arr);
 585                                 }
 586                                 else
 587                                         cb = new CustomAttributeBuilder (
 588                                                 (ConstructorInfo) constructor, pos_values);
 589                         } catch (Exception e) {
 590                                 //
 591                                 // Sample:
 592                                 // using System.ComponentModel;
 593                                 // [DefaultValue (CollectionChangeAction.Add)]
 594                                 // class X { static void Main () {} }
 595                                 //
 596                                 Error_AttributeArgumentNotValid (Location);
 597                                 return null;
 598                         }
 599
 600                         resolve_error = false;
 601                         return cb;
 602                 }
 603
 604                 /// <summary>
 605                 ///   Get a string containing a list of valid targets for the attribute 'attr'
 606                 /// </summary>
 607                 public string GetValidTargets ()
 608                 {
 609                         StringBuilder sb = new StringBuilder ();
 610                         AttributeTargets targets = GetAttributeUsage ().ValidOn;
 611
 612                         if ((targets & AttributeTargets.Assembly) != 0)
 613                                 sb.Append ("'assembly' ");
 614
 615                         if ((targets & AttributeTargets.Class) != 0)
 616                                 sb.Append ("'class' ");
 617
 618                         if ((targets & AttributeTargets.Constructor) != 0)
 619                                 sb.Append ("'constructor' ");
 620
 621                         if ((targets & AttributeTargets.Delegate) != 0)
 622                                 sb.Append ("'delegate' ");
 623
 624                         if ((targets & AttributeTargets.Enum) != 0)
 625                                 sb.Append ("'enum' ");
 626
 627                         if ((targets & AttributeTargets.Event) != 0)
 628                                 sb.Append ("'event' ");
 629
 630                         if ((targets & AttributeTargets.Field) != 0)
 631                                 sb.Append ("'field' ");
 632
 633                         if ((targets & AttributeTargets.Interface) != 0)
 634                                 sb.Append ("'interface' ");
 635
 636                         if ((targets & AttributeTargets.Method) != 0)
 637                                 sb.Append ("'method' ");
 638
 639                         if ((targets & AttributeTargets.Module) != 0)
 640                                 sb.Append ("'module' ");
 641
 642                         if ((targets & AttributeTargets.Parameter) != 0)
 643                                 sb.Append ("'parameter' ");
 644
 645                         if ((targets & AttributeTargets.Property) != 0)
 646                                 sb.Append ("'property' ");
 647
 648                         if ((targets & AttributeTargets.ReturnValue) != 0)
 649                                 sb.Append ("'return' ");
 650
 651                         if ((targets & AttributeTargets.Struct) != 0)
 652                                 sb.Append ("'struct' ");
 653
 654                         return sb.ToString ();
 655
 656                 }
 657
 658                 /// <summary>
 659                 /// Returns AttributeUsage attribute for this type
 660                 /// </summary>
 661                 public AttributeUsageAttribute GetAttributeUsage ()
 662                 {
 663                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 664                         if (ua != null)
 665                                 return ua;
 666
 667                         Class attr_class = TypeManager.LookupClass (Type);
 668
 669                         if (attr_class == null) {
 670                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 671                                 ua = (AttributeUsageAttribute)usage_attr [0];
 672                                 usage_attr_cache.Add (Type, ua);
 673                                 return ua;
 674                         }
 675
 676                         return attr_class.AttributeUsage;
 677                 }
 678
 679                 /// <summary>
 680                 /// Returns custom name of indexer
 681                 /// </summary>
 682                 public string GetIndexerAttributeValue (EmitContext ec)
 683                 {
 684                         if (pos_values == null)
 685                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 686                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 687                                 Resolve (ec);
 688
 689                         return pos_values [0] as string;
 690                 }
 691
 692                 /// <summary>
 693                 /// Returns condition of ConditionalAttribute
 694                 /// </summary>
 695                 public string GetConditionalAttributeValue (EmitContext ec)
 696                 {
 697                         if (pos_values == null)
 698                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 699                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 700                                 Resolve (ec);
 701
 702                         // Some error occurred
 703                         if (pos_values [0] == null)
 704                                 return null;
 705
 706                         return (string)pos_values [0];
 707                 }
 708
 709                 /// <summary>
 710                 /// Creates the instance of ObsoleteAttribute from this attribute instance
 711                 /// </summary>
 712                 public ObsoleteAttribute GetObsoleteAttribute (EmitContext ec)
 713                 {
 714                         if (pos_values == null)
 715                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 716                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 717                                 Resolve (ec);
 718
 719                         // Some error occurred
 720                         if (pos_values == null)
 721                                 return null;
 722
 723                         if (pos_values.Length == 0)
 724                                 return new ObsoleteAttribute ();
 725
 726                         if (pos_values.Length == 1)
 727                                 return new ObsoleteAttribute ((string)pos_values [0]);
 728
 729                         return new ObsoleteAttribute ((string)pos_values [0], (bool)pos_values [1]);
 730                 }
 731
 732                 /// <summary>
 733                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 734                 /// before ApplyAttribute. We need to resolve the arguments.
 735                 /// This situation occurs when class deps is differs from Emit order.
 736                 /// </summary>
 737                 public bool GetClsCompliantAttributeValue (EmitContext ec)
 738                 {
 739                         if (pos_values == null)
 740                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 741                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 742                                 Resolve (ec);
 743
 744                         // Some error occurred
 745                         if (pos_values [0] == null)
 746                                 return false;
 747
 748                         return (bool)pos_values [0];
 749                 }
 750
 751                 /// <summary>
 752                 /// Tests permitted SecurityAction for assembly or other types
 753                 /// </summary>
 754                 public bool CheckSecurityActionValidity (bool for_assembly)
 755                 {
 756                         SecurityAction action  = GetSecurityActionValue ();
 757
 758                         if ((action == SecurityAction.RequestMinimum || action == SecurityAction.RequestOptional || action == SecurityAction.RequestRefuse) && for_assembly)
 759                                 return true;
 760
 761                         if (!for_assembly) {
 762                                 if (action < SecurityAction.Demand || action > SecurityAction.InheritanceDemand) {
 763                                         Error_AttributeEmitError ("SecurityAction is out of range");
 764                                         return false;
 765                                 }
 766
 767                                 if ((action != SecurityAction.RequestMinimum && action != SecurityAction.RequestOptional && action != SecurityAction.RequestRefuse) && !for_assembly)
 768                                         return true;
 769                         }
 770
 771                         Error_AttributeEmitError (String.Concat ("SecurityAction '", action, "' is not valid for this declaration"));
 772                         return false;
 773                 }
 774
 775                 System.Security.Permissions.SecurityAction GetSecurityActionValue ()
 776                 {
 777                         return (SecurityAction)pos_values [0];
 778                 }
 779
 780                 /// <summary>
 781                 /// Creates instance of SecurityAttribute class and add result of CreatePermission method to permission table.
 782                 /// </summary>
 783                 /// <returns></returns>
 784                 public void ExtractSecurityPermissionSet (ListDictionary permissions)
 785                 {
 786                         if (TypeManager.LookupDeclSpace (Type) != null && RootContext.StdLib) {
 787                                 Error_AttributeEmitError ("security custom attributes can not be referenced from defining assembly");
 788                                 return;
 789                         }
 790
 791                         SecurityAttribute sa;
 792                         // For all assemblies except corlib we can avoid all hacks
 793                         if (RootContext.StdLib) {
 794                                 sa = (SecurityAttribute) Activator.CreateInstance (Type, pos_values);
 795
 796                                 if (prop_info_arr != null) {
 797                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 798                                                 PropertyInfo pi = prop_info_arr [i];
 799                                                 pi.SetValue (sa, prop_values_arr [i], null);
 800                                         }
 801                                 }
 802                         } else {
 803                                 Type temp_type = Type.GetType (Type.FullName);
 804                                 // HACK: All mscorlib attributes have same ctor syntax
 805                                 sa = (SecurityAttribute) Activator.CreateInstance (temp_type, new object[] { GetSecurityActionValue () } );
 806
 807                                 // All types are from newly created corlib but for invocation with old we need to convert them
 808                                 if (prop_info_arr != null) {
 809                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 810                                                 PropertyInfo emited_pi = prop_info_arr [i];
 811                                                 PropertyInfo pi = temp_type.GetProperty (emited_pi.Name, emited_pi.PropertyType);
 812
 813                                                 object old_instance = pi.PropertyType.IsEnum ?
 814                                                         System.Enum.ToObject (pi.PropertyType, prop_values_arr [i]) :
 815                                                         prop_values_arr [i];
 816
 817                                                 pi.SetValue (sa, old_instance, null);
 818                                         }
 819                                 }
 820                         }
 821
 822                         IPermission perm;
 823                         try {
 824                                 perm = sa.CreatePermission ();
 825                         }
 826                         catch (Exception e) {
 827                                 Error_AttributeEmitError (String.Format ("{0} was thrown during attribute processing: {1}", e.GetType (), e.Message));
 828                                 return;
 829                         }
 830                         SecurityAction action = GetSecurityActionValue ();
 831
 832                         // IS is correct because for corlib we are using an instance from old corlib
 833                         if (!(perm is System.Security.CodeAccessPermission)) {
 834                                 switch (action) {
 835                                         case SecurityAction.Demand:
 836                                                 action = (SecurityAction)13;
 837                                                 break;
 838                                         case SecurityAction.LinkDemand:
 839                                                 action = (SecurityAction)14;
 840                                                 break;
 841                                         case SecurityAction.InheritanceDemand:
 842                                                 action = (SecurityAction)15;
 843                                                 break;
 844                                 }
 845                         }
 846
 847                         PermissionSet ps = (PermissionSet)permissions [action];
 848                         if (ps == null) {
 849                                 if (sa is PermissionSetAttribute)
 850                                         ps = new PermissionSet (sa.Unrestricted ? PermissionState.Unrestricted : PermissionState.None);
 851                                 else
 852                                         ps = new PermissionSet (PermissionState.None);
 853
 854                                 permissions.Add (action, ps);
 855                         } else if (!ps.IsUnrestricted () && sa.Unrestricted) {
 856                                 ps = ps.Union (new PermissionSet (PermissionState.Unrestricted));
 857                                 permissions [action] = ps;
 858                         }
 859                         ps.AddPermission (perm);
 860                 }
 861
 862                 object GetValue (object value)
 863                 {
 864                         if (value is EnumConstant)
 865                                 return ((EnumConstant) value).GetValue ();
 866                         else
 867                                 return value;
 868                 }
 869
 870                 public object GetPositionalValue (int i)
 871                 {
 872                         return (pos_values == null) ? null : pos_values[i];
 873                 }
 874
 875                 object GetFieldValue (string name)
 876                 {
 877                         int i;
 878                         if (field_info_arr == null)
 879                                 return null;
 880                         i = 0;
 881                         foreach (FieldInfo fi in field_info_arr) {
 882                                 if (fi.Name == name)
 883                                         return GetValue (field_values_arr [i]);
 884                                 i++;
 885                         }
 886                         return null;
 887                 }
 888
 889                 public UnmanagedMarshal GetMarshal (Attributable attr)
 890                 {
 891                         object value = GetFieldValue ("SizeParamIndex");
 892                         if (value != null && UnmanagedType != UnmanagedType.LPArray) {
 893                                 Error_AttributeEmitError ("SizeParamIndex field is not valid for the specified unmanaged type");
 894                                 return null;
 895                         }
 896
 897                         object o = GetFieldValue ("ArraySubType");
 898                         UnmanagedType array_sub_type = o == null ? UnmanagedType.I4 : (UnmanagedType) o;
 899
 900                         switch (UnmanagedType) {
 901                         case UnmanagedType.CustomMarshaler:
 902                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
 903                                                                        BindingFlags.Static | BindingFlags.Public);
 904                                 if (define_custom == null) {
 905                                         Report.RuntimeMissingSupport (Location, "set marshal info");
 906                                         return null;
 907                                 }
 908
 909                                 object [] args = new object [4];
 910                                 args [0] = GetFieldValue ("MarshalTypeRef");
 911                                 args [1] = GetFieldValue ("MarshalCookie");
 912                                 args [2] = GetFieldValue ("MarshalType");
 913                                 args [3] = Guid.Empty;
 914                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
 915
 916                         case UnmanagedType.LPArray:
 917                                 return UnmanagedMarshal.DefineLPArray (array_sub_type);
 918
 919                         case UnmanagedType.SafeArray:
 920                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
 921
 922                         case UnmanagedType.ByValArray:
 923                                 FieldMember fm = attr as FieldMember;
 924                                 if (fm == null) {
 925                                         Error_AttributeEmitError ("Specified unmanaged type is only valid on fields");
 926                                         return null;
 927                                 }
 928                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
 929
 930                         case UnmanagedType.ByValTStr:
 931                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
 932
 933                         default:
 934                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
 935                         }
 936                 }
 937
 938                 public bool IsInternalCall
 939                 {
 940                         get { return ImplOptions == MethodImplOptions.InternalCall; }
 941                 }
 942
 943                 /// <summary>
 944                 /// Emit attribute for Attributable symbol
 945                 /// </summary>
 946                 public void Emit (EmitContext ec, Attributable ias, ListDictionary emitted_attr)
 947                 {
 948                         CustomAttributeBuilder cb = Resolve (ec);
 949                         if (cb == null)
 950                                 return;
 951
 952                         AttributeUsageAttribute usage_attr = GetAttributeUsage ();
 953                         if ((usage_attr.ValidOn & Target) == 0) {
 954                                 Report.Error (592, Location, "Attribute '{0}' is not valid on this declaration type. It is valid on {1} declarations only.", Name, GetValidTargets ());
 955                                 return;
 956                         }
 957
 958                         ias.ApplyAttributeBuilder (this, cb);
 959
 960                         if (!usage_attr.AllowMultiple) {
 961                                 ArrayList emitted_targets = (ArrayList)emitted_attr [Type];
 962                                 if (emitted_targets == null) {
 963                                         emitted_targets = new ArrayList ();
 964                                         emitted_attr.Add (Type, emitted_targets);
 965                                 } else if (emitted_targets.Contains (Target)) {
 966                                 Report.Error (579, Location, "Duplicate '" + Name + "' attribute");
 967                                         return;
 968                                 }
 969                                 emitted_targets.Add (Target);
 970                         }
 971
 972                         if (!RootContext.VerifyClsCompliance)
 973                                 return;
 974
 975                         // Here we are testing attribute arguments for array usage (error 3016)
 976                         if (ias.IsClsCompliaceRequired (ec.DeclSpace)) {
 977                                 if (Arguments == null)
 978                                         return;
 979
 980                                 ArrayList pos_args = (ArrayList) Arguments [0];
 981                                 if (pos_args != null) {
 982                                         foreach (Argument arg in pos_args) {
 983                                                 // Type is undefined (was error 246)
 984                                                 if (arg.Type == null)
 985                                                         return;
 986
 987                                                 if (arg.Type.IsArray) {
 988                                                         Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
 989                                                         return;
 990                                                 }
 991                                         }
 992                                 }
 993
 994                                 if (Arguments.Count < 2)
 995                                         return;
 996
 997                                 ArrayList named_args = (ArrayList) Arguments [1];
 998                                 foreach (DictionaryEntry de in named_args) {
 999                                         Argument arg  = (Argument) de.Value;
1000
1001                                         // Type is undefined (was error 246)
1002                                         if (arg.Type == null)
1003                                                 return;
1004
1005                                         if (arg.Type.IsArray) {
1006                                                 Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1007                                                 return;
1008                                         }
1009                                 }
1010                         }
1011                 }
1012
1013                 public object GetValue (EmitContext ec, Constant c, Type target)
1014                 {
1015                         if (Convert.ImplicitConversionExists (ec, c, target))
1016                                 return c.GetValue ();
1017
1018                         Convert.Error_CannotImplicitConversion (Location, c.Type, target);
1019                         return null;
1020                 }
1021
1022                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,
1023                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
1024                 {
1025                         //
1026                         // We extract from the attribute the information we need
1027                         //
1028
1029                         if (Arguments == null) {
1030                                 Console.WriteLine ("Internal error : this is not supposed to happen !");
1031                                 return null;
1032                         }
1033
1034                         ResolveType (ec);
1035                         if (Type == null)
1036                                 return null;
1037
1038                         ArrayList named_args = new ArrayList ();
1039
1040                         ArrayList pos_args = (ArrayList) Arguments [0];
1041                         if (Arguments.Count > 1)
1042                                 named_args = (ArrayList) Arguments [1];
1043
1044
1045                         string dll_name = null;
1046
1047                         Argument tmp = (Argument) pos_args [0];
1048
1049                         if (!tmp.Resolve (ec, Location))
1050                                 return null;
1051
1052                         if (tmp.Expr is Constant)
1053                                 dll_name = (string) ((Constant) tmp.Expr).GetValue ();
1054                         else {
1055                                 Error_AttributeArgumentNotValid (Location);
1056                                 return null;
1057                         }
1058                         if (dll_name == null || dll_name == ""){
1059                                 Error_AttributeArgumentNotValid (": DllImport requires a non-empty string", Location);
1060                                 return null;
1061                         }
1062
1063                         // Now we process the named arguments
1064                         CallingConvention cc = CallingConvention.Winapi;
1065                         CharSet charset = CharSet.Ansi;
1066                         bool preserve_sig = true;
1067 #if FIXME
1068                         bool exact_spelling = false;
1069 #endif
1070                         bool set_last_err = false;
1071                         string entry_point = null;
1072
1073                         for (int i = 0; i < named_args.Count; i++) {
1074
1075                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
1076
1077                                 string member_name = (string) de.Key;
1078                                 Argument a  = (Argument) de.Value;
1079
1080                                 if (!a.Resolve (ec, Location))
1081                                         return null;
1082
1083                                 Expression member = Expression.MemberLookup (
1084                                         ec, Type, member_name,
1085                                         MemberTypes.Field | MemberTypes.Property,
1086                                         BindingFlags.Public | BindingFlags.Instance,
1087                                         Location);
1088
1089                                 if (member == null || !(member is FieldExpr)) {
1090                                         Error_InvalidNamedArgument (member_name);
1091                                         return null;
1092                                 }
1093
1094                                 if (member is FieldExpr) {
1095                                         FieldExpr fe = (FieldExpr) member;
1096                                         FieldInfo fi = fe.FieldInfo;
1097
1098                                         if (fi.IsInitOnly) {
1099                                                 Error_InvalidNamedArgument (member_name);
1100                                                 return null;
1101                                         }
1102
1103                                         if (a.Expr is Constant) {
1104                                                 Constant c = (Constant) a.Expr;
1105
1106                                                 try {
1107                                                         if (member_name == "CallingConvention"){
1108                                                                 object val = GetValue (ec, c, typeof (CallingConvention));
1109                                                                 if (val == null)
1110                                                                         return null;
1111                                                                 cc = (CallingConvention) val;
1112                                                         } else if (member_name == "CharSet"){
1113                                                                 charset = (CharSet) c.GetValue ();
1114                                                         } else if (member_name == "EntryPoint")
1115                                                                 entry_point = (string) c.GetValue ();
1116                                                         else if (member_name == "SetLastError")
1117                                                                 set_last_err = (bool) c.GetValue ();
1118 #if FIXME
1119                                                         else if (member_name == "ExactSpelling")
1120                                                                 exact_spelling = (bool) c.GetValue ();
1121 #endif
1122                                                         else if (member_name == "PreserveSig")
1123                                                                 preserve_sig = (bool) c.GetValue ();
1124                                                 } catch (InvalidCastException){
1125                                                         Error_InvalidNamedArgument (member_name);
1126                                                         Error_AttributeArgumentNotValid (Location);
1127                                                 }
1128                                         } else {
1129                                                 Error_AttributeArgumentNotValid (Location);
1130                                                 return null;
1131                                         }
1132
1133                                 }
1134                         }
1135
1136                         if (entry_point == null)
1137                                 entry_point = name;
1138                         if (set_last_err)
1139                                 charset = (CharSet)((int)charset | 0x40);
1140
1141                         MethodBuilder mb = builder.DefinePInvokeMethod (
1142                                 name, dll_name, entry_point, flags | MethodAttributes.HideBySig,
1143                                 CallingConventions.Standard,
1144                                 ret_type,
1145                                 param_types,
1146                                 cc,
1147                                 charset);
1148
1149                         if (preserve_sig)
1150                                 mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1151
1152                         return mb;
1153                 }
1154
1155                 private Expression GetValue ()
1156                 {
1157                         if ((Arguments == null) || (Arguments.Count < 1))
1158                                 return null;
1159                         ArrayList al = (ArrayList) Arguments [0];
1160                         if ((al == null) || (al.Count < 1))
1161                                 return null;
1162                         Argument arg = (Argument) al [0];
1163                         if ((arg == null) || (arg.Expr == null))
1164                                 return null;
1165                         return arg.Expr;
1166                 }
1167
1168                 public string GetString ()
1169                 {
1170                         Expression e = GetValue ();
1171                         if (e is StringLiteral)
1172                                 return (e as StringLiteral).Value;
1173                         return null;
1174                 }
1175
1176                 public bool GetBoolean ()
1177                 {
1178                         Expression e = GetValue ();
1179                         if (e is BoolLiteral)
1180                                 return (e as BoolLiteral).Value;
1181                         return false;
1182                 }
1183         }
1184
1185
1186         /// <summary>
1187         /// For global attributes (assembly, module) we need special handling.
1188         /// Attributes can be located in the several files
1189         /// </summary>
1190         public class GlobalAttribute: Attribute
1191         {
1192                 public readonly NamespaceEntry ns;
1193
1194                 public GlobalAttribute (TypeContainer container, string target, string name, ArrayList args, Location loc):
1195                         base (target, name, args, loc)
1196                 {
1197                         ns = container.NamespaceEntry;
1198                 }
1199
1200                 protected override Type CheckAttributeType (EmitContext ec)
1201                 {
1202                         // RootContext.Tree.Types has a single NamespaceEntry which gets overwritten
1203                         // each time a new file is parsed.  However, we need to use the NamespaceEntry
1204                         // in effect where the attribute was used.  Since code elsewhere cannot assume
1205                         // that the NamespaceEntry is right, just overwrite it.
1206                         //
1207                         // Precondition: RootContext.Tree.Types == null || RootContext.Tree.Types == ns.
1208                         //               The second case happens when we are recursively invoked from inside Emit.
1209
1210                         NamespaceEntry old = null;
1211                         if (ec.DeclSpace == RootContext.Tree.Types) {
1212                                 old = ec.DeclSpace.NamespaceEntry;
1213                                 ec.DeclSpace.NamespaceEntry = ns;
1214                                 if (old != null && old != ns)
1215                                         throw new InternalErrorException (Location + " non-null NamespaceEntry " + old);
1216                         }
1217
1218                         Type retval = base.CheckAttributeType (ec);
1219
1220                         if (ec.DeclSpace == RootContext.Tree.Types)
1221                                 ec.DeclSpace.NamespaceEntry = old;
1222
1223                         return retval;
1224                 }
1225
1226                 public override CustomAttributeBuilder Resolve (EmitContext ec)
1227                 {
1228                         if (ec.DeclSpace == RootContext.Tree.Types) {
1229                                 NamespaceEntry old = ec.DeclSpace.NamespaceEntry;
1230                                 ec.DeclSpace.NamespaceEntry = ns;
1231                                 if (old != null)
1232                                         throw new InternalErrorException (Location + " non-null NamespaceEntry " + old);
1233                         }
1234
1235                         CustomAttributeBuilder retval = base.Resolve (ec);
1236
1237                         if (ec.DeclSpace == RootContext.Tree.Types)
1238                                 ec.DeclSpace.NamespaceEntry = null;
1239
1240                         return retval;
1241                 }
1242         }
1243
1244         public class Attributes {
1245                 public ArrayList Attrs;
1246
1247                 public Attributes (Attribute a)
1248                 {
1249                         Attrs = new ArrayList ();
1250                         Attrs.Add (a);
1251                 }
1252
1253                 public Attributes (ArrayList attrs)
1254                 {
1255                         Attrs = attrs;
1256                 }
1257
1258                 public void AddAttributes (ArrayList attrs)
1259                 {
1260                         Attrs.AddRange (attrs);
1261                 }
1262
1263                 /// <summary>
1264                 /// Checks whether attribute target is valid for the current element
1265                 /// </summary>
1266                 public bool CheckTargets (Attributable member)
1267                 {
1268                         string[] valid_targets = member.ValidAttributeTargets;
1269                         foreach (Attribute a in Attrs) {
1270                                 if (a.ExplicitTarget == null || a.ExplicitTarget == valid_targets [0]) {
1271                                         a.Target = member.AttributeTargets;
1272                                         continue;
1273                                 }
1274
1275                                 // TODO: we can skip the first item
1276                                 if (((IList) valid_targets).Contains (a.ExplicitTarget)) {
1277                                         switch (a.ExplicitTarget) {
1278                                                 case "return": a.Target = AttributeTargets.ReturnValue; continue;
1279                                                 case "param": a.Target = AttributeTargets.Parameter; continue;
1280                                                 case "field": a.Target = AttributeTargets.Field; continue;
1281                                                 case "method": a.Target = AttributeTargets.Method; continue;
1282                                                 case "property": a.Target = AttributeTargets.Property; continue;
1283                                         }
1284                                         throw new InternalErrorException ("Unknown explicit target: " + a.ExplicitTarget);
1285                                 }
1286
1287                                 StringBuilder sb = new StringBuilder ();
1288                                 foreach (string s in valid_targets) {
1289                                         sb.Append (s);
1290                                         sb.Append (", ");
1291                                 }
1292                                 sb.Remove (sb.Length - 2, 2);
1293                                 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 ());
1294                                 return false;
1295                         }
1296                         return true;
1297                 }
1298
1299                 public Attribute Search (Type t, EmitContext ec)
1300                 {
1301                         foreach (Attribute a in Attrs) {
1302                                 if (a.ResolveType (ec) == t)
1303                                         return a;
1304                         }
1305                         return null;
1306                 }
1307
1308                 /// <summary>
1309                 /// Returns all attributes of type 't'. Use it when attribute is AllowMultiple = true
1310                 /// </summary>
1311                 public Attribute[] SearchMulti (Type t, EmitContext ec)
1312                 {
1313                         ArrayList ar = null;
1314
1315                         foreach (Attribute a in Attrs) {
1316                                 if (a.ResolveType (ec) == t) {
1317                                         if (ar == null)
1318                                                 ar = new ArrayList ();
1319                                         ar.Add (a);
1320                                 }
1321                         }
1322
1323                         return ar == null ? null : ar.ToArray (typeof (Attribute)) as Attribute[];
1324                 }
1325
1326                 public void Emit (EmitContext ec, Attributable ias)
1327                 {
1328                         if (!CheckTargets (ias))
1329                                 return;
1330
1331                         ListDictionary ld = new ListDictionary ();
1332
1333                         foreach (Attribute a in Attrs)
1334                                 a.Emit (ec, ias, ld);
1335                 }
1336
1337                 public bool Contains (Type t, EmitContext ec)
1338                 {
1339                         return Search (t, ec) != null;
1340                 }
1341         }
1342
1343         /// <summary>
1344         /// Helper class for attribute verification routine.
1345         /// </summary>
1346         sealed class AttributeTester
1347         {
1348                 static PtrHashtable analyzed_types = new PtrHashtable ();
1349                 static PtrHashtable analyzed_types_obsolete = new PtrHashtable ();
1350                 static PtrHashtable analyzed_member_obsolete = new PtrHashtable ();
1351                 static PtrHashtable analyzed_method_excluded = new PtrHashtable ();
1352
1353                 private AttributeTester ()
1354                 {
1355                 }
1356
1357                 /// <summary>
1358                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1359                 /// It tests differing only in ref or out, or in array rank.
1360                 /// </summary>
1361                 public static bool AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1362                 {
1363                         if (types_a == null || types_b == null)
1364                                 return true;
1365
1366                         if (types_a.Length != types_b.Length)
1367                                 return true;
1368
1369                         for (int i = 0; i < types_b.Length; ++i) {
1370                                 Type aType = types_a [i];
1371                                 Type bType = types_b [i];
1372
1373                                 if (aType.IsArray && bType.IsArray && aType.GetArrayRank () != bType.GetArrayRank () && aType.GetElementType () == bType.GetElementType ()) {
1374                                         return false;
1375                                 }
1376
1377                                 Type aBaseType = aType;
1378                                 bool is_either_ref_or_out = false;
1379
1380                                 if (aType.IsByRef || aType.IsPointer) {
1381                                         aBaseType = aType.GetElementType ();
1382                                         is_either_ref_or_out = true;
1383                                 }
1384
1385                                 Type bBaseType = bType;
1386                                 if (bType.IsByRef || bType.IsPointer)
1387                                 {
1388                                         bBaseType = bType.GetElementType ();
1389                                         is_either_ref_or_out = !is_either_ref_or_out;
1390                                 }
1391
1392                                 if (aBaseType != bBaseType)
1393                                         continue;
1394
1395                                 if (is_either_ref_or_out)
1396                                         return false;
1397                         }
1398                         return true;
1399                 }
1400
1401                 /// <summary>
1402                 /// Goes through all parameters and test if they are CLS-Compliant.
1403                 /// </summary>
1404                 public static bool AreParametersCompliant (Parameter[] fixedParameters, Location loc)
1405                 {
1406                         if (fixedParameters == null)
1407                                 return true;
1408
1409                         foreach (Parameter arg in fixedParameters) {
1410                                 if (!AttributeTester.IsClsCompliant (arg.ParameterType)) {
1411                                         Report.Error (3001, loc, "Argument type '{0}' is not CLS-compliant", arg.GetSignatureForError ());
1412                                         return false;
1413                                 }
1414                         }
1415                         return true;
1416                 }
1417
1418
1419                 /// <summary>
1420                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1421                 /// </summary>
1422                 public static bool IsClsCompliant (Type type)
1423                 {
1424                         if (type == null)
1425                                 return true;
1426
1427                         object type_compliance = analyzed_types[type];
1428                         if (type_compliance != null)
1429                                 return type_compliance == TRUE;
1430
1431                         if (type.IsPointer) {
1432                                 analyzed_types.Add (type, null);
1433                                 return false;
1434                         }
1435
1436                         bool result;
1437                         if (type.IsArray || type.IsByRef)       {
1438                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1439                         } else {
1440                                 result = AnalyzeTypeCompliance (type);
1441                         }
1442                         analyzed_types.Add (type, result ? TRUE : FALSE);
1443                         return result;
1444                 }
1445
1446                 static object TRUE = new object ();
1447                 static object FALSE = new object ();
1448
1449                 public static void VerifyModulesClsCompliance ()
1450                 {
1451                         Module[] modules = TypeManager.Modules;
1452                         if (modules == null)
1453                                 return;
1454
1455                         // The first module is generated assembly
1456                         for (int i = 1; i < modules.Length; ++i) {
1457                                 Module module = modules [i];
1458                                 if (!IsClsCompliant (module)) {
1459                                         Report.Error (3013, "Added modules must be marked with the CLSCompliant attribute to match the assembly", module.Name);
1460                                         return;
1461                                 }
1462                         }
1463                 }
1464
1465                 /// <summary>
1466                 /// Tests container name for CLS-Compliant name (differing only in case)
1467                 /// </summary>
1468                 public static void VerifyTopLevelNameClsCompliance ()
1469                 {
1470                         Hashtable locase_table = new Hashtable ();
1471
1472                         // Convert imported type names to lower case and ignore not cls compliant
1473                         foreach (DictionaryEntry de in TypeManager.all_imported_types) {
1474                                 Type t = (Type)de.Value;
1475                                 if (!AttributeTester.IsClsCompliant (t))
1476                                         continue;
1477
1478                                 locase_table.Add (((string)de.Key).ToLower (System.Globalization.CultureInfo.InvariantCulture), t);
1479                         }
1480
1481                         foreach (DictionaryEntry de in RootContext.Tree.Decls) {
1482                                 DeclSpace decl = (DeclSpace)de.Value;
1483                                 if (!decl.IsClsCompliaceRequired (decl))
1484                                         continue;
1485
1486                                 string lcase = decl.Name.ToLower (System.Globalization.CultureInfo.InvariantCulture);
1487                                 if (!locase_table.Contains (lcase)) {
1488                                         locase_table.Add (lcase, decl);
1489                                         continue;
1490                                 }
1491
1492                                 object conflict = locase_table [lcase];
1493                                 if (conflict is Type)
1494                                         Report.SymbolRelatedToPreviousError ((Type)conflict);
1495                                 else
1496                                         Report.SymbolRelatedToPreviousError ((MemberCore)conflict);
1497
1498                                 Report.Error (3005, decl.Location, "Identifier '{0}' differing only in case is not CLS-compliant", decl.GetSignatureForError ());
1499                         }
1500                 }
1501
1502                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1503                 {
1504                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1505                         if (CompliantAttribute.Length == 0)
1506                                 return false;
1507
1508                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1509                 }
1510
1511                 static bool AnalyzeTypeCompliance (Type type)
1512                 {
1513                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1514                         if (ds != null) {
1515                                 return ds.IsClsCompliaceRequired (ds.Parent);
1516                         }
1517
1518                         if (type.IsGenericParameter || type.IsGenericInstance)
1519                                 return false;
1520
1521                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1522                         if (CompliantAttribute.Length == 0)
1523                                 return IsClsCompliant (type.Assembly);
1524
1525                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1526                 }
1527
1528                 /// <summary>
1529                 /// Returns instance of ObsoleteAttribute when type is obsolete
1530                 /// </summary>
1531                 public static ObsoleteAttribute GetObsoleteAttribute (Type type)
1532                 {
1533                         object type_obsolete = analyzed_types_obsolete [type];
1534                         if (type_obsolete == FALSE)
1535                                 return null;
1536
1537                         if (type_obsolete != null)
1538                                 return (ObsoleteAttribute)type_obsolete;
1539
1540                         ObsoleteAttribute result = null;
1541                         if (type.IsByRef || type.IsArray || type.IsPointer) {
1542                                 result = GetObsoleteAttribute (TypeManager.GetElementType (type));
1543                         } else if (type.IsGenericParameter || type.IsGenericInstance)
1544                                 return null;
1545                         else {
1546                                 DeclSpace type_ds = TypeManager.LookupDeclSpace (type);
1547
1548                                 // Type is external, we can get attribute directly
1549                                 if (type_ds == null) {
1550                                         object[] attribute = type.GetCustomAttributes (TypeManager.obsolete_attribute_type, false);
1551                                         if (attribute.Length == 1)
1552                                                 result = (ObsoleteAttribute)attribute [0];
1553                                 } else {
1554                                         result = type_ds.GetObsoleteAttribute (type_ds);
1555                                 }
1556                         }
1557
1558                         analyzed_types_obsolete.Add (type, result == null ? FALSE : result);
1559                         return result;
1560                 }
1561
1562                 /// <summary>
1563                 /// Returns instance of ObsoleteAttribute when method is obsolete
1564                 /// </summary>
1565                 public static ObsoleteAttribute GetMethodObsoleteAttribute (MethodBase mb)
1566                 {
1567                         IMethodData mc = TypeManager.GetMethod (mb);
1568                         if (mc != null)
1569                                 return mc.GetObsoleteAttribute ();
1570
1571                         // compiler generated methods are not registered by AddMethod
1572                         if (mb.DeclaringType is TypeBuilder)
1573                                 return null;
1574
1575                         PropertyInfo pi = PropertyExpr.AccessorTable [mb] as PropertyInfo;
1576                         if (pi != null)
1577                                 return GetMemberObsoleteAttribute (pi);
1578
1579                         return GetMemberObsoleteAttribute (mb);
1580                 }
1581
1582                 /// <summary>
1583                 /// Returns instance of ObsoleteAttribute when member is obsolete
1584                 /// </summary>
1585                 public static ObsoleteAttribute GetMemberObsoleteAttribute (MemberInfo mi)
1586                 {
1587                         object type_obsolete = analyzed_member_obsolete [mi];
1588                         if (type_obsolete == FALSE)
1589                                 return null;
1590
1591                         if (type_obsolete != null)
1592                                 return (ObsoleteAttribute)type_obsolete;
1593
1594                         if ((mi.DeclaringType is TypeBuilder) || mi.DeclaringType.IsGenericInstance)
1595                                 return null;
1596
1597                         ObsoleteAttribute oa = System.Attribute.GetCustomAttribute (mi, TypeManager.obsolete_attribute_type, false) as ObsoleteAttribute;
1598                         analyzed_member_obsolete.Add (mi, oa == null ? FALSE : oa);
1599                         return oa;
1600                 }
1601
1602                 /// <summary>
1603                 /// Common method for Obsolete error/warning reporting.
1604                 /// </summary>
1605                 public static void Report_ObsoleteMessage (ObsoleteAttribute oa, string member, Location loc)
1606                 {
1607                         if (oa.IsError) {
1608                                 Report.Error (619, loc, "'{0}' is obsolete: '{1}'", member, oa.Message);
1609                                 return;
1610                         }
1611
1612                         if (oa.Message == null) {
1613                                 Report.Warning (612, loc, "'{0}' is obsolete", member);
1614                                 return;
1615                         }
1616                         if (RootContext.WarningLevel >= 2)
1617                                 Report.Warning (618, loc, "'{0}' is obsolete: '{1}'", member, oa.Message);
1618                 }
1619
1620                 public static bool IsConditionalMethodExcluded (MethodBase mb)
1621                 {
1622                         object excluded = analyzed_method_excluded [mb];
1623                         if (excluded != null)
1624                                 return excluded == TRUE ? true : false;
1625
1626                         if (mb.Mono_IsInflatedMethod)
1627                                 return false;
1628
1629                         ConditionalAttribute[] attrs = mb.GetCustomAttributes (TypeManager.conditional_attribute_type, true) as ConditionalAttribute[];
1630                         if (attrs.Length == 0) {
1631                                 analyzed_method_excluded.Add (mb, FALSE);
1632                                 return false;
1633                         }
1634
1635                         foreach (ConditionalAttribute a in attrs) {
1636                                 if (RootContext.AllDefines.Contains (a.ConditionString)) {
1637                                         analyzed_method_excluded.Add (mb, FALSE);
1638                                         return false;
1639                                 }
1640                         }
1641                         analyzed_method_excluded.Add (mb, TRUE);
1642                         return true;
1643                 }
1644         }
1645 }