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 using System.IO;
  25
  26 namespace Mono.CSharp {
  27
  28         /// <summary>
  29         ///   Base class for objects that can have Attributes applied to them.
  30         /// </summary>
  31         public abstract class Attributable {
  32                 /// <summary>
  33                 ///   Attributes for this type
  34                 /// </summary>
  35                 protected Attributes attributes;
  36
  37                 public Attributable (Attributes attrs)
  38                 {
  39                         if (attrs != null)
  40                                 OptAttributes = attrs;
  41                 }
  42
  43                 public Attributes OptAttributes
  44                 {
  45                         get {
  46                                 return attributes;
  47                         }
  48                         set {
  49                                 attributes = value;
  50
  51                                 if (attributes != null) {
  52                                         attributes.AttachTo (this);
  53                                 }
  54                         }
  55                 }
  56
  57                 /// <summary>
  58                 /// Use member-specific procedure to apply attribute @a in @cb to the entity being built in @builder
  59                 /// </summary>
  60                 public abstract void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb);
  61
  62                 /// <summary>
  63                 /// Returns one AttributeTarget for this element.
  64                 /// </summary>
  65                 public abstract AttributeTargets AttributeTargets { get; }
  66
  67                 public abstract IResolveContext ResolveContext { get; }
  68
  69                 public abstract bool IsClsComplianceRequired ();
  70
  71                 /// <summary>
  72                 /// Gets list of valid attribute targets for explicit target declaration.
  73                 /// The first array item is default target. Don't break this rule.
  74                 /// </summary>
  75                 public abstract string[] ValidAttributeTargets { get; }
  76         };
  77
  78         public class Attribute {
  79                 public readonly string ExplicitTarget;
  80                 public AttributeTargets Target;
  81
  82                 // TODO: remove this member
  83                 public readonly string    Name;
  84                 public readonly Expression LeftExpr;
  85                 public readonly string Identifier;
  86
  87                 readonly ArrayList PosArguments;
  88                 readonly ArrayList NamedArguments;
  89
  90                 public readonly Location Location;
  91
  92                 public Type Type;
  93
  94                 bool resolve_error;
  95                 readonly bool nameEscaped;
  96
  97                 // It can contain more onwers when the attribute is applied to multiple fiels.
  98                 Attributable[] owners;
  99
 100                 static readonly AttributeUsageAttribute DefaultUsageAttribute = new AttributeUsageAttribute (AttributeTargets.All);
 101                 static Assembly orig_sec_assembly;
 102                 public static readonly object[] EmptyObject = new object [0];
 103
 104                 // non-null if named args present after Resolve () is called
 105                 PropertyInfo [] prop_info_arr;
 106                 FieldInfo [] field_info_arr;
 107                 object [] field_values_arr;
 108                 object [] prop_values_arr;
 109                 object [] pos_values;
 110
 111                 static PtrHashtable usage_attr_cache;
 112                 // Cache for parameter-less attributes
 113                 static PtrHashtable att_cache;
 114
 115                 public Attribute (string target, Expression left_expr, string identifier, object[] args, Location loc, bool nameEscaped)
 116                 {
 117                         LeftExpr = left_expr;
 118                         Identifier = identifier;
 119                         Name = LeftExpr == null ? identifier : LeftExpr + "." + identifier;
 120                         if (args != null) {
 121                                 PosArguments = (ArrayList)args [0];
 122                                 NamedArguments = (ArrayList)args [1];
 123                         }
 124                         Location = loc;
 125                         ExplicitTarget = target;
 126                         this.nameEscaped = nameEscaped;
 127                 }
 128
 129                 static Attribute ()
 130                 {
 131                         Reset ();
 132                 }
 133
 134                 public static void Reset ()
 135                 {
 136                         usage_attr_cache = new PtrHashtable ();
 137                         att_cache = new PtrHashtable ();
 138                 }
 139
 140                 public void AttachTo (Attributable owner)
 141                 {
 142                         if (this.owners == null) {
 143                                 this.owners = new Attributable[1] { owner };
 144                                 return;
 145                         }
 146
 147                         // When the same attribute is attached to multiple fiels
 148                         // we use this extra_owners as a list of owners. The attribute
 149                         // then can be removed because will be emitted when first owner
 150                         // is served
 151                         Attributable[] new_array = new Attributable [this.owners.Length + 1];
 152                         owners.CopyTo (new_array, 0);
 153                         new_array [owners.Length] = owner;
 154                         this.owners = new_array;
 155                         owner.OptAttributes = null;
 156                 }
 157
 158                 void Error_InvalidNamedArgument (string name)
 159                 {
 160                         Report.Error (617, Location, "`{0}' is not a valid named attribute argument. Named attribute arguments " +
 161                                       "must be fields which are not readonly, static, const or read-write properties which are " +
 162                                       "public and not static",
 163                               name);
 164                 }
 165
 166                 void Error_InvalidNamedAgrumentType (string name)
 167                 {
 168                         Report.Error (655, Location, "`{0}' is not a valid named attribute argument because it is not a valid " +
 169                                       "attribute parameter type", name);
 170                 }
 171
 172                 public static void Error_AttributeArgumentNotValid (Location loc)
 173                 {
 174                         Report.Error (182, loc,
 175                                       "An attribute argument must be a constant expression, typeof " +
 176                                       "expression or array creation expression");
 177                 }
 178
 179                 static void Error_TypeParameterInAttribute (Location loc)
 180                 {
 181                         Report.Error (
 182                                 -202, loc, "Can not use a type parameter in an attribute");
 183                 }
 184
 185                 public void Error_MissingGuidAttribute ()
 186                 {
 187                         Report.Error (596, Location, "The Guid attribute must be specified with the ComImport attribute");
 188                 }
 189
 190                 /// <summary>
 191                 /// This is rather hack. We report many emit attribute error with same error to be compatible with
 192                 /// csc. But because csc has to report them this way because error came from ilasm we needn't.
 193                 /// </summary>
 194                 public void Error_AttributeEmitError (string inner)
 195                 {
 196                         Report.Error (647, Location, "Error during emitting `{0}' attribute. The reason is `{1}'",
 197                                       TypeManager.CSharpName (Type), inner);
 198                 }
 199
 200                 public void Error_InvalidSecurityParent ()
 201                 {
 202                         Error_AttributeEmitError ("it is attached to invalid parent");
 203                 }
 204
 205                 Attributable Owner {
 206                         get {
 207                                 return owners [0];
 208                         }
 209                 }
 210
 211                 protected virtual TypeExpr ResolveAsTypeTerminal (Expression expr, IResolveContext ec, bool silent)
 212                 {
 213                         return expr.ResolveAsTypeTerminal (ec, silent);
 214                 }
 215
 216                 Type ResolvePossibleAttributeType (string name, bool silent, ref bool is_attr)
 217                 {
 218                         IResolveContext rc = Owner.ResolveContext;
 219
 220                         TypeExpr te;
 221                         if (LeftExpr == null) {
 222                                 te = ResolveAsTypeTerminal (new SimpleName (name, Location), rc, silent);
 223                         } else {
 224                                 te = ResolveAsTypeTerminal (new MemberAccess (LeftExpr, name), rc, silent);
 225                         }
 226
 227                         if (te == null)
 228                                 return null;
 229
 230                         Type t = te.Type;
 231                         if (TypeManager.IsSubclassOf (t, TypeManager.attribute_type)) {
 232                                 is_attr = true;
 233                         } else if (!silent) {
 234                                 Report.SymbolRelatedToPreviousError (t);
 235                                 Report.Error (616, Location, "`{0}': is not an attribute class", TypeManager.CSharpName (t));
 236                         }
 237                         return t;
 238                 }
 239
 240                 /// <summary>
 241                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 242                 /// </summary>
 243                 void ResolveAttributeType ()
 244                 {
 245                         bool t1_is_attr = false;
 246                         Type t1 = ResolvePossibleAttributeType (Identifier, true, ref t1_is_attr);
 247
 248                         bool t2_is_attr = false;
 249                         Type t2 = nameEscaped ? null :
 250                                 ResolvePossibleAttributeType (Identifier + "Attribute", true, ref t2_is_attr);
 251
 252                         if (t1_is_attr && t2_is_attr) {
 253                                 Report.Error (1614, Location, "`{0}' is ambiguous between `{0}' and `{0}Attribute'. " +
 254                                               "Use either `@{0}' or `{0}Attribute'", GetSignatureForError ());
 255                                 resolve_error = true;
 256                                 return;
 257                         }
 258
 259                         if (t1_is_attr) {
 260                                 Type = t1;
 261                                 return;
 262                         }
 263
 264                         if (t2_is_attr) {
 265                                 Type = t2;
 266                                 return;
 267                         }
 268
 269                         if (t1 == null && t2 == null)
 270                                 ResolvePossibleAttributeType (Identifier, false, ref t1_is_attr);
 271                         if (t1 != null)
 272                                 ResolvePossibleAttributeType (Identifier, false, ref t1_is_attr);
 273                         if (t2 != null)
 274                                 ResolvePossibleAttributeType (Identifier + "Attribute", false, ref t2_is_attr);
 275
 276                         resolve_error = true;
 277                 }
 278
 279                 public virtual Type ResolveType ()
 280                 {
 281                         if (Type == null && !resolve_error)
 282                                 ResolveAttributeType ();
 283                         return Type;
 284                 }
 285
 286                 public string GetSignatureForError ()
 287                 {
 288                         if (Type != null)
 289                                 return TypeManager.CSharpName (Type);
 290
 291                         return LeftExpr == null ? Identifier : LeftExpr.GetSignatureForError () + "." + Identifier;
 292                 }
 293
 294                 bool IsValidArgumentType (Type t)
 295                 {
 296                         if (t.IsArray)
 297                                 t = t.GetElementType ();
 298
 299                         return TypeManager.IsPrimitiveType (t) ||
 300                                 TypeManager.IsEnumType (t) ||
 301                                 t == TypeManager.string_type ||
 302                                 t == TypeManager.object_type ||
 303                                 t == TypeManager.type_type;
 304                 }
 305
 306                 public CustomAttributeBuilder Resolve ()
 307                 {
 308                         if (resolve_error)
 309                                 return null;
 310
 311                         resolve_error = true;
 312
 313                         if (Type == null) {
 314                                 ResolveAttributeType ();
 315                                 if (Type == null)
 316                                         return null;
 317                         }
 318
 319                         if (Type.IsAbstract) {
 320                                 Report.Error (653, Location, "Cannot apply attribute class `{0}' because it is abstract", GetSignatureForError ());
 321                                 return null;
 322                         }
 323
 324                         ObsoleteAttribute obsolete_attr = AttributeTester.GetObsoleteAttribute (Type);
 325                         if (obsolete_attr != null) {
 326                                 AttributeTester.Report_ObsoleteMessage (obsolete_attr, TypeManager.CSharpName (Type), Location);
 327                         }
 328
 329                         if (PosArguments == null && NamedArguments == null) {
 330                                 object o = att_cache [Type];
 331                                 if (o != null) {
 332                                         resolve_error = false;
 333                                         return (CustomAttributeBuilder)o;
 334                                 }
 335                         }
 336
 337                         Attributable owner = Owner;
 338                         EmitContext ec = new EmitContext (owner.ResolveContext, owner.ResolveContext.DeclContainer, owner.ResolveContext.DeclContainer,
 339                                 Location, null, null, owner.ResolveContext.DeclContainer.ModFlags, false);
 340                         ec.IsAnonymousMethodAllowed = false;
 341
 342                         ConstructorInfo ctor = ResolveConstructor (ec);
 343                         if (ctor == null) {
 344                                 if (Type is TypeBuilder &&
 345                                     TypeManager.LookupDeclSpace (Type).MemberCache == null)
 346                                         // The attribute type has been DefineType'd, but not Defined.  Let's not treat it as an error.
 347                                         // It'll be resolved again when the attached-to entity is emitted.
 348                                         resolve_error = false;
 349                                 return null;
 350                         }
 351
 352                         CustomAttributeBuilder cb;
 353
 354                         try {
 355                                 if (NamedArguments == null) {
 356                                         cb = new CustomAttributeBuilder (ctor, pos_values);
 357
 358                                         if (pos_values.Length == 0)
 359                                                 att_cache.Add (Type, cb);
 360
 361                                         resolve_error = false;
 362                                         return cb;
 363                                 }
 364
 365                                 if (!ResolveNamedArguments (ec)) {
 366                                         return null;
 367                                 }
 368
 369                                 cb = new CustomAttributeBuilder (ctor, pos_values,
 370                                                 prop_info_arr, prop_values_arr,
 371                                                 field_info_arr, field_values_arr);
 372
 373                                 resolve_error = false;
 374                                 return cb;
 375                         }
 376                         catch (Exception) {
 377                                 Error_AttributeArgumentNotValid (Location);
 378                                 return null;
 379                         }
 380                 }
 381
 382                 protected virtual ConstructorInfo ResolveConstructor (EmitContext ec)
 383                 {
 384                         if (PosArguments != null) {
 385                                 for (int i = 0; i < PosArguments.Count; i++) {
 386                                         Argument a = (Argument) PosArguments [i];
 387
 388                                         if (!a.Resolve (ec, Location))
 389                                                 return null;
 390                                 }
 391                         }
 392
 393                         Expression mg = Expression.MemberLookup (ec.ContainerType,
 394                                 Type, ".ctor", MemberTypes.Constructor,
 395                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 396                                 Location);
 397
 398                         if (mg == null)
 399                                 return null;
 400
 401                         MethodBase constructor = Invocation.OverloadResolve (
 402                                 ec, (MethodGroupExpr) mg, PosArguments, false, Location);
 403
 404                         if (constructor == null)
 405                                 return null;
 406
 407                         ObsoleteAttribute oa = AttributeTester.GetMethodObsoleteAttribute (constructor);
 408                         if (oa != null && !Owner.ResolveContext.IsInObsoleteScope) {
 409                                 AttributeTester.Report_ObsoleteMessage (oa, mg.GetSignatureForError (), mg.Location);
 410                         }
 411
 412                         if (PosArguments == null) {
 413                                 pos_values = EmptyObject;
 414                                 return (ConstructorInfo)constructor;
 415                         }
 416
 417                         ParameterData pd = TypeManager.GetParameterData (constructor);
 418
 419                         int pos_arg_count = PosArguments.Count;
 420                         int last_real_param = pd.Count;
 421
 422                         pos_values = new object [pos_arg_count];
 423
 424                         if (pd.HasParams) {
 425                                 // When the params is not filled we need to put one
 426                                 if (last_real_param > pos_arg_count) {
 427                                         object [] new_pos_values = new object [pos_arg_count + 1];
 428                                         pos_values.CopyTo (new_pos_values, 0);
 429                                         new_pos_values [pos_arg_count] = new object [] {} ;
 430                                         pos_values = new_pos_values;
 431                                 }
 432                                 last_real_param--;
 433                         }
 434
 435                         for (int j = 0; j < pos_arg_count; ++j) {
 436                                 Argument a = (Argument) PosArguments [j];
 437
 438                                 if (!a.Expr.GetAttributableValue (a.Type, out pos_values [j]))
 439                                         return null;
 440
 441                                 if (j < last_real_param)
 442                                         continue;
 443
 444                                 if (j == last_real_param) {
 445                                         object [] array = new object [pos_arg_count - last_real_param];
 446                                         array [0] = pos_values [j];
 447                                         pos_values [j] = array;
 448                                         continue;
 449                                 }
 450
 451                                 object [] params_array = (object []) pos_values [last_real_param];
 452                                 params_array [j - last_real_param] = pos_values [j];
 453                         }
 454
 455                         // Adjust the size of the pos_values if it had params
 456                         if (last_real_param != pos_arg_count) {
 457                                 object [] new_pos_values = new object [last_real_param + 1];
 458                                 Array.Copy (pos_values, new_pos_values, last_real_param + 1);
 459                                 pos_values = new_pos_values;
 460                         }
 461
 462                         // Here we do the checks which should be done by corlib or by runtime.
 463                         // However Zoltan doesn't like it and every Mono compiler has to do it again.
 464
 465                         if (Type == TypeManager.guid_attr_type) {
 466                                 try {
 467                                         new Guid ((string)pos_values [0]);
 468                                 }
 469                                 catch (Exception e) {
 470                                         Error_AttributeEmitError (e.Message);
 471                                         return null;
 472                                 }
 473                         }
 474
 475                         if (Type == TypeManager.attribute_usage_type && (int)pos_values [0] == 0) {
 476                                 Report.Error (591, Location, "Invalid value for argument to `System.AttributeUsage' attribute");
 477                                 return null;
 478                         }
 479
 480                         if (Type == TypeManager.indexer_name_type || Type == TypeManager.conditional_attribute_type) {
 481                                 if (!Tokenizer.IsValidIdentifier ((string)pos_values [0])) {
 482                                         Report.Error (633, ((Argument)PosArguments[0]).Expr.Location,
 483                                                 "The argument to the `{0}' attribute must be a valid identifier", GetSignatureForError ());
 484                                         return null;
 485                                 }
 486                         }
 487
 488                         if (Type == TypeManager.methodimpl_attr_type && pos_values.Length == 1 &&
 489                                 pd.ParameterType (0) == TypeManager.short_type &&
 490                                 !System.Enum.IsDefined (typeof (MethodImplOptions), pos_values [0].ToString ())) {
 491                                 Error_AttributeEmitError ("Incorrect argument value.");
 492                                 return null;
 493                         }
 494
 495                         return (ConstructorInfo)constructor;
 496                 }
 497
 498                 protected virtual bool ResolveNamedArguments (EmitContext ec)
 499                 {
 500                         int named_arg_count = NamedArguments.Count;
 501
 502                         ArrayList field_infos = new ArrayList (named_arg_count);
 503                         ArrayList prop_infos  = new ArrayList (named_arg_count);
 504                         ArrayList field_values = new ArrayList (named_arg_count);
 505                         ArrayList prop_values = new ArrayList (named_arg_count);
 506
 507                         ArrayList seen_names = new ArrayList(named_arg_count);
 508
 509                         foreach (DictionaryEntry de in NamedArguments) {
 510                                 string member_name = (string) de.Key;
 511
 512                                 if (seen_names.Contains(member_name)) {
 513                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 514                                         return false;
 515                                 }
 516                                 seen_names.Add(member_name);
 517
 518                                 Argument a = (Argument) de.Value;
 519                                 if (!a.Resolve (ec, Location))
 520                                         return false;
 521
 522                                 Expression member = Expression.MemberLookup (
 523                                         ec.ContainerType, Type, member_name,
 524                                         MemberTypes.Field | MemberTypes.Property,
 525                                         BindingFlags.Public | BindingFlags.Instance,
 526                                         Location);
 527
 528                                 if (member == null) {
 529                                         member = Expression.MemberLookup (ec.ContainerType, Type, member_name,
 530                                                 MemberTypes.Field | MemberTypes.Property, BindingFlags.NonPublic | BindingFlags.Instance,
 531                                                 Location);
 532
 533                                         if (member != null) {
 534                                                 Report.SymbolRelatedToPreviousError (member.Type);
 535                                                 Expression.ErrorIsInaccesible (Location, member.GetSignatureForError ());
 536                                                 return false;
 537                                         }
 538                                 }
 539
 540                                 if (member == null){
 541                                         Report.Error (117, Location, "`{0}' does not contain a definition for `{1}'",
 542                                                       TypeManager.CSharpName (Type), member_name);
 543                                         return false;
 544                                 }
 545
 546                                 if (!(member is PropertyExpr || member is FieldExpr)) {
 547                                         Error_InvalidNamedArgument (member_name);
 548                                         return false;
 549                                 }
 550
 551                                 if (a.Expr is TypeParameterExpr){
 552                                         Error_TypeParameterInAttribute (Location);
 553                                         return false;
 554                                 }
 555
 556                                 ObsoleteAttribute obsolete_attr;
 557
 558                                 if (member is PropertyExpr) {
 559                                         PropertyInfo pi = ((PropertyExpr) member).PropertyInfo;
 560
 561                                         if (!pi.CanWrite || !pi.CanRead) {
 562                                                 Report.SymbolRelatedToPreviousError (pi);
 563                                                 Error_InvalidNamedArgument (member_name);
 564                                                 return false;
 565                                         }
 566
 567                                         if (!IsValidArgumentType (pi.PropertyType)) {
 568                                                 Report.SymbolRelatedToPreviousError (pi);
 569                                                 Error_InvalidNamedAgrumentType (member_name);
 570                                                 return false;
 571                                         }
 572
 573                                         object value;
 574                                         if (!a.Expr.GetAttributableValue (pi.PropertyType, out value))
 575                                                 return false;
 576
 577                                         PropertyBase pb = TypeManager.GetProperty (pi);
 578                                         if (pb != null)
 579                                                 obsolete_attr = pb.GetObsoleteAttribute ();
 580                                         else
 581                                                 obsolete_attr = AttributeTester.GetMemberObsoleteAttribute (pi);
 582
 583                                         prop_values.Add (value);
 584                                         prop_infos.Add (pi);
 585
 586                                 } else {
 587                                         FieldInfo fi = ((FieldExpr) member).FieldInfo;
 588
 589                                         if (fi.IsInitOnly) {
 590                                                 Error_InvalidNamedArgument (member_name);
 591                                                 return false;
 592                                         }
 593
 594                                         if (!IsValidArgumentType (fi.FieldType)) {
 595                                                 Report.SymbolRelatedToPreviousError (fi);
 596                                                 Error_InvalidNamedAgrumentType (member_name);
 597                                                 return false;
 598                                         }
 599
 600                                         object value;
 601                                         if (!a.Expr.GetAttributableValue (fi.FieldType, out value))
 602                                                 return false;
 603
 604                                         FieldBase fb = TypeManager.GetField (fi);
 605                                         if (fb != null)
 606                                                 obsolete_attr = fb.GetObsoleteAttribute ();
 607                                         else
 608                                                 obsolete_attr = AttributeTester.GetMemberObsoleteAttribute (fi);
 609
 610                                         field_values.Add (value);
 611                                         field_infos.Add (fi);
 612                                 }
 613
 614                                 if (obsolete_attr != null && !Owner.ResolveContext.IsInObsoleteScope)
 615                                         AttributeTester.Report_ObsoleteMessage (obsolete_attr, member.GetSignatureForError (), member.Location);
 616                         }
 617
 618                         prop_info_arr = new PropertyInfo [prop_infos.Count];
 619                         field_info_arr = new FieldInfo [field_infos.Count];
 620                         field_values_arr = new object [field_values.Count];
 621                         prop_values_arr = new object [prop_values.Count];
 622
 623                         field_infos.CopyTo  (field_info_arr, 0);
 624                         field_values.CopyTo (field_values_arr, 0);
 625
 626                         prop_values.CopyTo  (prop_values_arr, 0);
 627                         prop_infos.CopyTo   (prop_info_arr, 0);
 628
 629                         return true;
 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.Module) != 0)
 644                                 sb.Append ("module, ");
 645
 646                         if ((targets & AttributeTargets.Class) != 0)
 647                                 sb.Append ("class, ");
 648
 649                         if ((targets & AttributeTargets.Struct) != 0)
 650                                 sb.Append ("struct, ");
 651
 652                         if ((targets & AttributeTargets.Enum) != 0)
 653                                 sb.Append ("enum, ");
 654
 655                         if ((targets & AttributeTargets.Constructor) != 0)
 656                                 sb.Append ("constructor, ");
 657
 658                         if ((targets & AttributeTargets.Method) != 0)
 659                                 sb.Append ("method, ");
 660
 661                         if ((targets & AttributeTargets.Property) != 0)
 662                                 sb.Append ("property, indexer, ");
 663
 664                         if ((targets & AttributeTargets.Field) != 0)
 665                                 sb.Append ("field, ");
 666
 667                         if ((targets & AttributeTargets.Event) != 0)
 668                                 sb.Append ("event, ");
 669
 670                         if ((targets & AttributeTargets.Interface) != 0)
 671                                 sb.Append ("interface, ");
 672
 673                         if ((targets & AttributeTargets.Parameter) != 0)
 674                                 sb.Append ("parameter, ");
 675
 676                         if ((targets & AttributeTargets.Delegate) != 0)
 677                                 sb.Append ("delegate, ");
 678
 679                         if ((targets & AttributeTargets.ReturnValue) != 0)
 680                                 sb.Append ("return, ");
 681
 682                         if ((targets & AttributeTargets.GenericParameter) != 0)
 683                                 sb.Append ("type parameter, ");
 684                         return sb.Remove (sb.Length - 2, 2).ToString ();
 685                 }
 686
 687                 /// <summary>
 688                 /// Returns AttributeUsage attribute for this type
 689                 /// </summary>
 690                 AttributeUsageAttribute GetAttributeUsage ()
 691                 {
 692                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 693                         if (ua != null)
 694                                 return ua;
 695
 696                         Class attr_class = TypeManager.LookupClass (Type);
 697
 698                         if (attr_class == null) {
 699                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 700                                 ua = (AttributeUsageAttribute)usage_attr [0];
 701                                 usage_attr_cache.Add (Type, ua);
 702                                 return ua;
 703                         }
 704
 705                         Attribute a = attr_class.OptAttributes == null
 706                                 ? null
 707                                 : attr_class.OptAttributes.Search (TypeManager.attribute_usage_type);
 708
 709                         ua = a == null
 710                                 ? DefaultUsageAttribute
 711                                 : a.GetAttributeUsageAttribute ();
 712
 713                         usage_attr_cache.Add (Type, ua);
 714                         return ua;
 715                 }
 716
 717                 AttributeUsageAttribute GetAttributeUsageAttribute ()
 718                 {
 719                         if (pos_values == null)
 720                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 721                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 722                                 Resolve ();
 723
 724                         if (resolve_error)
 725                                 return DefaultUsageAttribute;
 726
 727                         AttributeUsageAttribute usage_attribute = new AttributeUsageAttribute ((AttributeTargets)pos_values [0]);
 728
 729                         object field = GetPropertyValue ("AllowMultiple");
 730                         if (field != null)
 731                                 usage_attribute.AllowMultiple = (bool)field;
 732
 733                         field = GetPropertyValue ("Inherited");
 734                         if (field != null)
 735                                 usage_attribute.Inherited = (bool)field;
 736
 737                         return usage_attribute;
 738                 }
 739
 740                 /// <summary>
 741                 /// Returns custom name of indexer
 742                 /// </summary>
 743                 public string GetIndexerAttributeValue ()
 744                 {
 745                         if (pos_values == null)
 746                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 747                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 748                                 Resolve ();
 749
 750                         if (resolve_error)
 751                                 return null;
 752
 753                         return pos_values [0] as string;
 754                 }
 755
 756                 /// <summary>
 757                 /// Returns condition of ConditionalAttribute
 758                 /// </summary>
 759                 public string GetConditionalAttributeValue ()
 760                 {
 761                         if (pos_values == null)
 762                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 763                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 764                                 Resolve ();
 765
 766                         if (resolve_error)
 767                                 return null;
 768
 769                         return (string)pos_values [0];
 770                 }
 771
 772                 /// <summary>
 773                 /// Creates the instance of ObsoleteAttribute from this attribute instance
 774                 /// </summary>
 775                 public ObsoleteAttribute GetObsoleteAttribute ()
 776                 {
 777                         if (pos_values == null)
 778                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 779                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 780                                 Resolve ();
 781
 782                         if (resolve_error)
 783                                 return null;
 784
 785                         if (pos_values == null || pos_values.Length == 0)
 786                                 return new ObsoleteAttribute ();
 787
 788                         if (pos_values.Length == 1)
 789                                 return new ObsoleteAttribute ((string)pos_values [0]);
 790
 791                         return new ObsoleteAttribute ((string)pos_values [0], (bool)pos_values [1]);
 792                 }
 793
 794                 /// <summary>
 795                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 796                 /// before ApplyAttribute. We need to resolve the arguments.
 797                 /// This situation occurs when class deps is differs from Emit order.
 798                 /// </summary>
 799                 public bool GetClsCompliantAttributeValue ()
 800                 {
 801                         if (pos_values == null)
 802                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 803                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 804                                 Resolve ();
 805
 806                         if (resolve_error)
 807                                 return false;
 808
 809                         return (bool)pos_values [0];
 810                 }
 811
 812                 public Type GetCoClassAttributeValue ()
 813                 {
 814                         if (pos_values == null)
 815                                 Resolve ();
 816
 817                         if (resolve_error)
 818                                 return null;
 819
 820                         return (Type)pos_values [0];
 821                 }
 822
 823                 public bool CheckTarget ()
 824                 {
 825                         string[] valid_targets = Owner.ValidAttributeTargets;
 826                         if (ExplicitTarget == null || ExplicitTarget == valid_targets [0]) {
 827                                 Target = Owner.AttributeTargets;
 828                                 return true;
 829                         }
 830
 831                         // TODO: we can skip the first item
 832                         if (((IList) valid_targets).Contains (ExplicitTarget)) {
 833                                 switch (ExplicitTarget) {
 834                                         case "return": Target = AttributeTargets.ReturnValue; return true;
 835                                         case "param": Target = AttributeTargets.Parameter; return true;
 836                                         case "field": Target = AttributeTargets.Field; return true;
 837                                         case "method": Target = AttributeTargets.Method; return true;
 838                                         case "property": Target = AttributeTargets.Property; return true;
 839                                 }
 840                                 throw new InternalErrorException ("Unknown explicit target: " + ExplicitTarget);
 841                         }
 842
 843                         StringBuilder sb = new StringBuilder ();
 844                         foreach (string s in valid_targets) {
 845                                 sb.Append (s);
 846                                 sb.Append (", ");
 847                         }
 848                         sb.Remove (sb.Length - 2, 2);
 849                         Report.Error (657, Location, "`{0}' is not a valid attribute location for this declaration. " +
 850                                 "Valid attribute locations for this declaration are `{1}'", ExplicitTarget, sb.ToString ());
 851                         return false;
 852                 }
 853
 854                 /// <summary>
 855                 /// Tests permitted SecurityAction for assembly or other types
 856                 /// </summary>
 857                 public bool CheckSecurityActionValidity (bool for_assembly)
 858                 {
 859                         SecurityAction action = GetSecurityActionValue ();
 860
 861                         switch (action) {
 862                         case SecurityAction.Demand:
 863                         case SecurityAction.Assert:
 864                         case SecurityAction.Deny:
 865                         case SecurityAction.PermitOnly:
 866                         case SecurityAction.LinkDemand:
 867                         case SecurityAction.InheritanceDemand:
 868                                 if (!for_assembly)
 869                                         return true;
 870                                 break;
 871
 872                         case SecurityAction.RequestMinimum:
 873                         case SecurityAction.RequestOptional:
 874                         case SecurityAction.RequestRefuse:
 875                                 if (for_assembly)
 876                                         return true;
 877                                 break;
 878
 879                         default:
 880                                 Error_AttributeEmitError ("SecurityAction is out of range");
 881                                 return false;
 882                         }
 883
 884                         Error_AttributeEmitError (String.Concat ("SecurityAction `", action, "' is not valid for this declaration"));
 885                         return false;
 886                 }
 887
 888                 System.Security.Permissions.SecurityAction GetSecurityActionValue ()
 889                 {
 890                         return (SecurityAction)pos_values [0];
 891                 }
 892
 893                 /// <summary>
 894                 /// Creates instance of SecurityAttribute class and add result of CreatePermission method to permission table.
 895                 /// </summary>
 896                 /// <returns></returns>
 897                 public void ExtractSecurityPermissionSet (ListDictionary permissions)
 898                 {
 899                         Type orig_assembly_type = null;
 900
 901                         if (TypeManager.LookupDeclSpace (Type) != null) {
 902                                 if (!RootContext.StdLib) {
 903                                         orig_assembly_type = Type.GetType (Type.FullName);
 904                                 } else {
 905                                         string orig_version_path = Environment.GetEnvironmentVariable ("__SECURITY_BOOTSTRAP_DB");
 906                                         if (orig_version_path == null) {
 907                                                 Error_AttributeEmitError ("security custom attributes can not be referenced from defining assembly");
 908                                                 return;
 909                                         }
 910
 911                                         if (orig_sec_assembly == null) {
 912                                                 string file = Path.Combine (orig_version_path, Driver.OutputFile);
 913                                                 orig_sec_assembly = Assembly.LoadFile (file);
 914                                         }
 915
 916                                         orig_assembly_type = orig_sec_assembly.GetType (Type.FullName, true);
 917                                         if (orig_assembly_type == null) {
 918                                                 Report.Warning (-112, 1, Location, "Self-referenced security attribute `{0}' " +
 919                                                                 "was not found in previous version of assembly");
 920                                                 return;
 921                                         }
 922                                 }
 923                         }
 924
 925                         SecurityAttribute sa;
 926                         // For all non-selfreferencing security attributes we can avoid all hacks
 927                         if (orig_assembly_type == null) {
 928                                 sa = (SecurityAttribute) Activator.CreateInstance (Type, pos_values);
 929
 930                                 if (prop_info_arr != null) {
 931                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 932                                                 PropertyInfo pi = prop_info_arr [i];
 933                                                 pi.SetValue (sa, prop_values_arr [i], null);
 934                                         }
 935                                 }
 936                         } else {
 937                                 // HACK: All security attributes have same ctor syntax
 938                                 sa = (SecurityAttribute) Activator.CreateInstance (orig_assembly_type, new object[] { GetSecurityActionValue () } );
 939
 940                                 // All types are from newly created assembly but for invocation with old one we need to convert them
 941                                 if (prop_info_arr != null) {
 942                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 943                                                 PropertyInfo emited_pi = prop_info_arr [i];
 944                                                 PropertyInfo pi = orig_assembly_type.GetProperty (emited_pi.Name, emited_pi.PropertyType);
 945
 946                                                 object old_instance = pi.PropertyType.IsEnum ?
 947                                                         System.Enum.ToObject (pi.PropertyType, prop_values_arr [i]) :
 948                                                         prop_values_arr [i];
 949
 950                                                 pi.SetValue (sa, old_instance, null);
 951                                         }
 952                                 }
 953                         }
 954
 955                         IPermission perm;
 956                         perm = sa.CreatePermission ();
 957                         SecurityAction action = GetSecurityActionValue ();
 958
 959                         // IS is correct because for corlib we are using an instance from old corlib
 960                         if (!(perm is System.Security.CodeAccessPermission)) {
 961                                 switch (action) {
 962                                         case SecurityAction.Demand:
 963                                                 action = (SecurityAction)13;
 964                                                 break;
 965                                         case SecurityAction.LinkDemand:
 966                                                 action = (SecurityAction)14;
 967                                                 break;
 968                                         case SecurityAction.InheritanceDemand:
 969                                                 action = (SecurityAction)15;
 970                                                 break;
 971                                 }
 972                         }
 973
 974                         PermissionSet ps = (PermissionSet)permissions [action];
 975                         if (ps == null) {
 976                                 if (sa is PermissionSetAttribute)
 977                                         ps = new PermissionSet (sa.Unrestricted ? PermissionState.Unrestricted : PermissionState.None);
 978                                 else
 979                                         ps = new PermissionSet (PermissionState.None);
 980
 981                                 permissions.Add (action, ps);
 982                         } else if (!ps.IsUnrestricted () && (sa is PermissionSetAttribute) && sa.Unrestricted) {
 983                                 ps = ps.Union (new PermissionSet (PermissionState.Unrestricted));
 984                                 permissions [action] = ps;
 985                         }
 986                         ps.AddPermission (perm);
 987                 }
 988
 989                 static object GetValue (object value)
 990                 {
 991                         if (value is EnumConstant)
 992                                 return ((EnumConstant) value).GetValue ();
 993                         else
 994                                 return value;
 995                 }
 996
 997                 public object GetPropertyValue (string name)
 998                 {
 999                         if (prop_info_arr == null)
1000                                 return null;
1001
1002                         for (int i = 0; i < prop_info_arr.Length; ++i) {
1003                                 if (prop_info_arr [i].Name == name)
1004                                         return prop_values_arr [i];
1005                         }
1006
1007                         return null;
1008                 }
1009
1010                 object GetFieldValue (string name)
1011                 {
1012                         int i;
1013                         if (field_info_arr == null)
1014                                 return null;
1015                         i = 0;
1016                         foreach (FieldInfo fi in field_info_arr) {
1017                                 if (fi.Name == name)
1018                                         return GetValue (field_values_arr [i]);
1019                                 i++;
1020                         }
1021                         return null;
1022                 }
1023
1024                 //
1025                 // Theoretically, we can get rid of this, since FieldBuilder.SetCustomAttribute()
1026                 // and ParameterBuilder.SetCustomAttribute() are supposed to handle this attribute.
1027                 // However, we can't, since it appears that the .NET 1.1 SRE hangs when given a MarshalAsAttribute.
1028                 //
1029                 public UnmanagedMarshal GetMarshal (Attributable attr)
1030                 {
1031                         UnmanagedType UnmanagedType;
1032                         if (!RootContext.StdLib || pos_values [0].GetType () != typeof (UnmanagedType))
1033                                 UnmanagedType = (UnmanagedType) System.Enum.ToObject (typeof (UnmanagedType), pos_values [0]);
1034                         else
1035                                 UnmanagedType = (UnmanagedType) pos_values [0];
1036
1037                         object value = GetFieldValue ("SizeParamIndex");
1038                         if (value != null && UnmanagedType != UnmanagedType.LPArray) {
1039                                 Error_AttributeEmitError ("SizeParamIndex field is not valid for the specified unmanaged type");
1040                                 return null;
1041                         }
1042
1043                         object o = GetFieldValue ("ArraySubType");
1044                         UnmanagedType array_sub_type = o == null ? (UnmanagedType) 0x50 /* NATIVE_MAX */ : (UnmanagedType) o;
1045
1046                         switch (UnmanagedType) {
1047                         case UnmanagedType.CustomMarshaler: {
1048                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
1049                                         BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
1050                                 if (define_custom == null) {
1051                                         Report.RuntimeMissingSupport (Location, "set marshal info");
1052                                         return null;
1053                                 }
1054
1055                                 object [] args = new object [4];
1056                                 args [0] = GetFieldValue ("MarshalTypeRef");
1057                                 args [1] = GetFieldValue ("MarshalCookie");
1058                                 args [2] = GetFieldValue ("MarshalType");
1059                                 args [3] = Guid.Empty;
1060                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
1061                         }
1062                         case UnmanagedType.LPArray: {
1063                                 object size_const = GetFieldValue ("SizeConst");
1064                                 object size_param_index = GetFieldValue ("SizeParamIndex");
1065
1066                                 if ((size_const != null) || (size_param_index != null)) {
1067                                         MethodInfo define_array = typeof (UnmanagedMarshal).GetMethod ("DefineLPArrayInternal",
1068                                                 BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
1069                                         if (define_array == null) {
1070                                                 Report.RuntimeMissingSupport (Location, "set marshal info");
1071                                                 return null;
1072                                         }
1073
1074                                         object [] args = new object [3];
1075                                         args [0] = array_sub_type;
1076                                         args [1] = size_const == null ? -1 : size_const;
1077                                         args [2] = size_param_index == null ? -1 : size_param_index;
1078                                         return (UnmanagedMarshal) define_array.Invoke (null, args);
1079                                 }
1080                                 else
1081                                         return UnmanagedMarshal.DefineLPArray (array_sub_type);
1082                         }
1083                         case UnmanagedType.SafeArray:
1084                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
1085
1086                         case UnmanagedType.ByValArray:
1087                                 FieldMember fm = attr as FieldMember;
1088                                 if (fm == null) {
1089                                         Error_AttributeEmitError ("Specified unmanaged type is only valid on fields");
1090                                         return null;
1091                                 }
1092                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
1093
1094                         case UnmanagedType.ByValTStr:
1095                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
1096
1097                         default:
1098                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
1099                         }
1100                 }
1101
1102                 public CharSet GetCharSetValue ()
1103                 {
1104                         return (CharSet)System.Enum.Parse (typeof (CharSet), pos_values [0].ToString ());
1105                 }
1106
1107                 public MethodImplOptions GetMethodImplOptions ()
1108                 {
1109                         if (pos_values [0].GetType () != typeof (MethodImplOptions))
1110                                 return (MethodImplOptions)System.Enum.ToObject (typeof (MethodImplOptions), pos_values [0]);
1111                         return (MethodImplOptions)pos_values [0];
1112                 }
1113
1114                 public LayoutKind GetLayoutKindValue ()
1115                 {
1116                         if (!RootContext.StdLib || pos_values [0].GetType () != typeof (LayoutKind))
1117                                 return (LayoutKind)System.Enum.ToObject (typeof (LayoutKind), pos_values [0]);
1118
1119                         return (LayoutKind)pos_values [0];
1120                 }
1121
1122                 public object GetParameterDefaultValue ()
1123                 {
1124                         return pos_values [0];
1125                 }
1126
1127                 public override bool Equals (object obj)
1128                 {
1129                         Attribute a = obj as Attribute;
1130                         if (a == null)
1131                                 return false;
1132
1133                         return Type == a.Type && Target == a.Target;
1134                 }
1135
1136                 public override int GetHashCode ()
1137                 {
1138                         return base.GetHashCode ();
1139                 }
1140
1141                 /// <summary>
1142                 /// Emit attribute for Attributable symbol
1143                 /// </summary>
1144                 public void Emit (ListDictionary allEmitted)
1145                 {
1146                         CustomAttributeBuilder cb = Resolve ();
1147                         if (cb == null)
1148                                 return;
1149
1150                         AttributeUsageAttribute usage_attr = GetAttributeUsage ();
1151                         if ((usage_attr.ValidOn & Target) == 0) {
1152                                 Report.Error (592, Location, "The attribute `{0}' is not valid on this declaration type. " +
1153                                               "It is valid on `{1}' declarations only",
1154                                         GetSignatureForError (), GetValidTargets ());
1155                                 return;
1156                         }
1157
1158                         try {
1159                                 foreach (Attributable owner in owners)
1160                                         owner.ApplyAttributeBuilder (this, cb);
1161                         }
1162                         catch (Exception e) {
1163                                 Error_AttributeEmitError (e.Message);
1164                                 return;
1165                         }
1166
1167                         if (!usage_attr.AllowMultiple && allEmitted != null) {
1168                                 if (allEmitted.Contains (this)) {
1169                                         ArrayList a = allEmitted [this] as ArrayList;
1170                                         if (a == null) {
1171                                                 a = new ArrayList (2);
1172                                                 allEmitted [this] = a;
1173                                         }
1174                                         a.Add (this);
1175                                 } else {
1176                                         allEmitted.Add (this, null);
1177                                 }
1178                         }
1179
1180                         if (!RootContext.VerifyClsCompliance)
1181                                 return;
1182
1183                         // Here we are testing attribute arguments for array usage (error 3016)
1184                         if (Owner.IsClsComplianceRequired ()) {
1185                                 if (PosArguments != null) {
1186                                         foreach (Argument arg in PosArguments) {
1187                                                 // Type is undefined (was error 246)
1188                                                 if (arg.Type == null)
1189                                                         return;
1190
1191                                                 if (arg.Type.IsArray) {
1192                                                         Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1193                                                         return;
1194                                                 }
1195                                         }
1196                                 }
1197
1198                                 if (NamedArguments == null)
1199                                         return;
1200
1201                                 foreach (DictionaryEntry de in NamedArguments) {
1202                                         Argument arg  = (Argument) de.Value;
1203
1204                                         // Type is undefined (was error 246)
1205                                         if (arg.Type == null)
1206                                                 return;
1207
1208                                         if (arg.Type.IsArray) {
1209                                                 Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1210                                                 return;
1211                                         }
1212                                 }
1213                         }
1214                 }
1215
1216                 public MethodBuilder DefinePInvokeMethod (TypeBuilder builder, string name,
1217                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
1218                 {
1219                         if (pos_values == null)
1220                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
1221                                 // But because a lot of attribute class code must be rewritten will be better to wait...
1222                                 Resolve ();
1223
1224                         if (resolve_error)
1225                                 return null;
1226
1227                         string dll_name = (string)pos_values [0];
1228
1229                         // Default settings
1230                         CallingConvention cc = CallingConvention.Winapi;
1231                         CharSet charset = CodeGen.Module.DefaultCharSet;
1232                         bool preserve_sig = true;
1233                         string entry_point = name;
1234                         bool best_fit_mapping = false;
1235                         bool throw_on_unmappable = false;
1236                         bool exact_spelling = false;
1237                         bool set_last_error = false;
1238
1239                         bool best_fit_mapping_set = false;
1240                         bool throw_on_unmappable_set = false;
1241                         bool exact_spelling_set = false;
1242                         bool set_last_error_set = false;
1243
1244                         MethodInfo set_best_fit = null;
1245                         MethodInfo set_throw_on = null;
1246                         MethodInfo set_exact_spelling = null;
1247                         MethodInfo set_set_last_error = null;
1248
1249                         if (field_info_arr != null) {
1250
1251                                 for (int i = 0; i < field_info_arr.Length; i++) {
1252                                         switch (field_info_arr [i].Name) {
1253                                         case "BestFitMapping":
1254                                                 best_fit_mapping = (bool) field_values_arr [i];
1255                                                 best_fit_mapping_set = true;
1256                                                 break;
1257                                         case "CallingConvention":
1258                                                 cc = (CallingConvention) field_values_arr [i];
1259                                                 break;
1260                                         case "CharSet":
1261                                                 charset = (CharSet) field_values_arr [i];
1262                                                 break;
1263                                         case "EntryPoint":
1264                                                 entry_point = (string) field_values_arr [i];
1265                                                 break;
1266                                         case "ExactSpelling":
1267                                                 exact_spelling = (bool) field_values_arr [i];
1268                                                 exact_spelling_set = true;
1269                                                 break;
1270                                         case "PreserveSig":
1271                                                 preserve_sig = (bool) field_values_arr [i];
1272                                                 break;
1273                                         case "SetLastError":
1274                                                 set_last_error = (bool) field_values_arr [i];
1275                                                 set_last_error_set = true;
1276                                                 break;
1277                                         case "ThrowOnUnmappableChar":
1278                                                 throw_on_unmappable = (bool) field_values_arr [i];
1279                                                 throw_on_unmappable_set = true;
1280                                                 break;
1281                                         default:
1282                                                 throw new InternalErrorException (field_info_arr [i].ToString ());
1283                                         }
1284                                 }
1285                         }
1286
1287                         if (throw_on_unmappable_set || best_fit_mapping_set || exact_spelling_set || set_last_error_set) {
1288                                 set_best_fit = typeof (MethodBuilder).
1289                                         GetMethod ("set_BestFitMapping", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1290                                 set_throw_on = typeof (MethodBuilder).
1291                                         GetMethod ("set_ThrowOnUnmappableChar", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1292                                 set_exact_spelling = typeof (MethodBuilder).
1293                                         GetMethod ("set_ExactSpelling", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1294                                 set_set_last_error = typeof (MethodBuilder).
1295                                         GetMethod ("set_SetLastError", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1296
1297                                 if ((set_best_fit == null) || (set_throw_on == null) ||
1298                                     (set_exact_spelling == null) || (set_set_last_error == null)) {
1299                                         Report.Error (-1, Location,
1300                                                                   "The ThrowOnUnmappableChar, BestFitMapping, SetLastError, " +
1301                                                       "and ExactSpelling attributes can only be emitted when running on the mono runtime.");
1302                                         return null;
1303                                 }
1304                         }
1305
1306                         try {
1307                                 MethodBuilder mb = builder.DefinePInvokeMethod (
1308                                         name, dll_name, entry_point, flags | MethodAttributes.HideBySig | MethodAttributes.PinvokeImpl,
1309                                         CallingConventions.Standard, ret_type, param_types, cc, charset);
1310
1311                                 if (preserve_sig)
1312                                         mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1313
1314                                 if (throw_on_unmappable_set)
1315                                         set_throw_on.Invoke (mb, 0, null, new object [] { throw_on_unmappable }, null);
1316                                 if (best_fit_mapping_set)
1317                                         set_best_fit.Invoke (mb, 0, null, new object [] { best_fit_mapping }, null);
1318                                 if (exact_spelling_set)
1319                                         set_exact_spelling.Invoke  (mb, 0, null, new object [] { exact_spelling }, null);
1320                                 if (set_last_error_set)
1321                                         set_set_last_error.Invoke  (mb, 0, null, new object [] { set_last_error }, null);
1322
1323                                 return mb;
1324                         }
1325                         catch (ArgumentException e) {
1326                                 Error_AttributeEmitError (e.Message);
1327                                 return null;
1328                         }
1329                 }
1330
1331                 private Expression GetValue ()
1332                 {
1333                         if (PosArguments == null || PosArguments.Count < 1)
1334                                 return null;
1335
1336                         return ((Argument) PosArguments [0]).Expr;
1337                 }
1338
1339                 public string GetString ()
1340                 {
1341                         Expression e = GetValue ();
1342                         if (e is StringLiteral)
1343                                 return (e as StringLiteral).Value;
1344                         return null;
1345                 }
1346
1347                 public bool GetBoolean ()
1348                 {
1349                         Expression e = GetValue ();
1350                         if (e is BoolLiteral)
1351                                 return (e as BoolLiteral).Value;
1352                         return false;
1353                 }
1354
1355                 public Type GetArgumentType ()
1356                 {
1357                         TypeOf e = GetValue () as TypeOf;
1358                         if (e == null)
1359                                 return null;
1360                         return e.TypeArgument;
1361                 }
1362         }
1363
1364
1365         /// <summary>
1366         /// For global attributes (assembly, module) we need special handling.
1367         /// Attributes can be located in the several files
1368         /// </summary>
1369         public class GlobalAttribute : Attribute
1370         {
1371                 public readonly NamespaceEntry ns;
1372
1373                 public GlobalAttribute (NamespaceEntry ns, string target,
1374                                         Expression left_expr, string identifier, object[] args, Location loc, bool nameEscaped):
1375                         base (target, left_expr, identifier, args, loc, nameEscaped)
1376                 {
1377                         this.ns = ns;
1378                 }
1379
1380                 void Enter ()
1381                 {
1382                         // RootContext.ToplevelTypes has a single NamespaceEntry which gets overwritten
1383                         // each time a new file is parsed.  However, we need to use the NamespaceEntry
1384                         // in effect where the attribute was used.  Since code elsewhere cannot assume
1385                         // that the NamespaceEntry is right, just overwrite it.
1386                         //
1387                         // Precondition: RootContext.ToplevelTypes == null
1388
1389                         if (RootContext.ToplevelTypes.NamespaceEntry != null)
1390                                 throw new InternalErrorException (Location + " non-null NamespaceEntry");
1391
1392                         RootContext.ToplevelTypes.NamespaceEntry = ns;
1393                 }
1394
1395                 void Leave ()
1396                 {
1397                         RootContext.ToplevelTypes.NamespaceEntry = null;
1398                 }
1399
1400                 protected override TypeExpr ResolveAsTypeTerminal (Expression expr, IResolveContext ec, bool silent)
1401                 {
1402                         try {
1403                                 Enter ();
1404                                 return base.ResolveAsTypeTerminal (expr, ec, silent);
1405                         }
1406                         finally {
1407                                 Leave ();
1408                         }
1409                 }
1410
1411                 protected override ConstructorInfo ResolveConstructor (EmitContext ec)
1412                 {
1413                         try {
1414                                 Enter ();
1415                                 return base.ResolveConstructor (ec);
1416                         }
1417                         finally {
1418                                 Leave ();
1419                         }
1420                 }
1421
1422                 protected override bool ResolveNamedArguments (EmitContext ec)
1423                 {
1424                         try {
1425                                 Enter ();
1426                                 return base.ResolveNamedArguments (ec);
1427                         }
1428                         finally {
1429                                 Leave ();
1430                         }
1431                 }
1432         }
1433
1434         public class Attributes {
1435                 public readonly ArrayList Attrs;
1436
1437                 public Attributes (Attribute a)
1438                 {
1439                         Attrs = new ArrayList ();
1440                         Attrs.Add (a);
1441                 }
1442
1443                 public Attributes (ArrayList attrs)
1444                 {
1445                         Attrs = attrs;
1446                 }
1447
1448                 public void AddAttributes (ArrayList attrs)
1449                 {
1450                         Attrs.AddRange (attrs);
1451                 }
1452
1453                 public void AttachTo (Attributable attributable)
1454                 {
1455                         foreach (Attribute a in Attrs)
1456                                 a.AttachTo (attributable);
1457                 }
1458
1459                 /// <summary>
1460                 /// Checks whether attribute target is valid for the current element
1461                 /// </summary>
1462                 public bool CheckTargets ()
1463                 {
1464                         foreach (Attribute a in Attrs) {
1465                                 if (!a.CheckTarget ())
1466                                         return false;
1467                         }
1468                         return true;
1469                 }
1470
1471                 public Attribute Search (Type t)
1472                 {
1473                         foreach (Attribute a in Attrs) {
1474                                 if (a.ResolveType () == t)
1475                                         return a;
1476                         }
1477                         return null;
1478                 }
1479
1480                 /// <summary>
1481                 /// Returns all attributes of type 't'. Use it when attribute is AllowMultiple = true
1482                 /// </summary>
1483                 public Attribute[] SearchMulti (Type t)
1484                 {
1485                         ArrayList ar = null;
1486
1487                         foreach (Attribute a in Attrs) {
1488                                 if (a.ResolveType () == t) {
1489                                         if (ar == null)
1490                                                 ar = new ArrayList ();
1491                                         ar.Add (a);
1492                                 }
1493                         }
1494
1495                         return ar == null ? null : ar.ToArray (typeof (Attribute)) as Attribute[];
1496                 }
1497
1498                 public void Emit ()
1499                 {
1500                         CheckTargets ();
1501
1502                         ListDictionary ld = Attrs.Count > 1 ? new ListDictionary () : null;
1503
1504                         foreach (Attribute a in Attrs)
1505                                 a.Emit (ld);
1506
1507                         if (ld == null || ld.Count == 0)
1508                                 return;
1509
1510                         foreach (DictionaryEntry d in ld) {
1511                                 if (d.Value == null)
1512                                         continue;
1513
1514                                 foreach (Attribute collision in (ArrayList)d.Value)
1515                                         Report.SymbolRelatedToPreviousError (collision.Location, "");
1516
1517                                 Attribute a = (Attribute)d.Key;
1518                                 Report.Error (579, a.Location, "The attribute `{0}' cannot be applied multiple times", a.GetSignatureForError ());
1519                         }
1520                 }
1521
1522                 public bool Contains (Type t)
1523                 {
1524                         return Search (t) != null;
1525                 }
1526         }
1527
1528         /// <summary>
1529         /// Helper class for attribute verification routine.
1530         /// </summary>
1531         sealed class AttributeTester
1532         {
1533                 static PtrHashtable analyzed_types;
1534                 static PtrHashtable analyzed_types_obsolete;
1535                 static PtrHashtable analyzed_member_obsolete;
1536                 static PtrHashtable analyzed_method_excluded;
1537
1538 #if NET_2_0
1539                 static PtrHashtable fixed_buffer_cache;
1540 #endif
1541
1542                 static object TRUE = new object ();
1543                 static object FALSE = new object ();
1544
1545                 static AttributeTester ()
1546                 {
1547                         Reset ();
1548                 }
1549
1550                 private AttributeTester ()
1551                 {
1552                 }
1553
1554                 public static void Reset ()
1555                 {
1556                         analyzed_types = new PtrHashtable ();
1557                         analyzed_types_obsolete = new PtrHashtable ();
1558                         analyzed_member_obsolete = new PtrHashtable ();
1559                         analyzed_method_excluded = new PtrHashtable ();
1560 #if NET_2_0
1561                         fixed_buffer_cache = new PtrHashtable ();
1562 #endif
1563                 }
1564
1565                 public enum Result {
1566                         Ok,
1567                         RefOutArrayError,
1568                         ArrayArrayError
1569                 }
1570
1571                 /// <summary>
1572                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1573                 /// It tests differing only in ref or out, or in array rank.
1574                 /// </summary>
1575                 public static Result AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1576                 {
1577                         if (types_a == null || types_b == null)
1578                                 return Result.Ok;
1579
1580                         if (types_a.Length != types_b.Length)
1581                                 return Result.Ok;
1582
1583                         Result result = Result.Ok;
1584                         for (int i = 0; i < types_b.Length; ++i) {
1585                                 Type aType = types_a [i];
1586                                 Type bType = types_b [i];
1587
1588                                 if (aType.IsArray && bType.IsArray) {
1589                                         Type a_el_type = aType.GetElementType ();
1590                                         Type b_el_type = bType.GetElementType ();
1591                                         if (aType.GetArrayRank () != bType.GetArrayRank () && a_el_type == b_el_type) {
1592                                                 result = Result.RefOutArrayError;
1593                                                 continue;
1594                                         }
1595
1596                                         if (a_el_type.IsArray || b_el_type.IsArray) {
1597                                                 result = Result.ArrayArrayError;
1598                                                 continue;
1599                                         }
1600                                 }
1601
1602                                 Type aBaseType = aType;
1603                                 bool is_either_ref_or_out = false;
1604
1605                                 if (aType.IsByRef || aType.IsPointer) {
1606                                         aBaseType = aType.GetElementType ();
1607                                         is_either_ref_or_out = true;
1608                                 }
1609
1610                                 Type bBaseType = bType;
1611                                 if (bType.IsByRef || bType.IsPointer)
1612                                 {
1613                                         bBaseType = bType.GetElementType ();
1614                                         is_either_ref_or_out = !is_either_ref_or_out;
1615                                 }
1616
1617                                 if (aBaseType != bBaseType)
1618                                         return Result.Ok;
1619
1620                                 if (is_either_ref_or_out)
1621                                         result = Result.RefOutArrayError;
1622                         }
1623                         return result;
1624                 }
1625
1626                 /// <summary>
1627                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1628                 /// </summary>
1629                 public static bool IsClsCompliant (Type type)
1630                 {
1631                         if (type == null)
1632                                 return true;
1633
1634                         object type_compliance = analyzed_types[type];
1635                         if (type_compliance != null)
1636                                 return type_compliance == TRUE;
1637
1638                         if (type.IsPointer) {
1639                                 analyzed_types.Add (type, null);
1640                                 return false;
1641                         }
1642
1643                         bool result;
1644                         if (type.IsArray || type.IsByRef)       {
1645                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1646                         } else {
1647                                 result = AnalyzeTypeCompliance (type);
1648                         }
1649                         analyzed_types.Add (type, result ? TRUE : FALSE);
1650                         return result;
1651                 }
1652
1653                 /// <summary>
1654                 /// Returns IFixedBuffer implementation if field is fixed buffer else null.
1655                 /// </summary>
1656                 public static IFixedBuffer GetFixedBuffer (FieldInfo fi)
1657                 {
1658                         FieldBase fb = TypeManager.GetField (fi);
1659                         if (fb != null) {
1660                                 return fb as IFixedBuffer;
1661                         }
1662
1663 #if NET_2_0
1664                         object o = fixed_buffer_cache [fi];
1665                         if (o == null) {
1666                                 if (System.Attribute.GetCustomAttribute (fi, TypeManager.fixed_buffer_attr_type) == null) {
1667                                         fixed_buffer_cache.Add (fi, FALSE);
1668                                         return null;
1669                                 }
1670
1671                                 IFixedBuffer iff = new FixedFieldExternal (fi);
1672                                 fixed_buffer_cache.Add (fi, iff);
1673                                 return iff;
1674                         }
1675
1676                         if (o == FALSE)
1677                                 return null;
1678
1679                         return (IFixedBuffer)o;
1680 #else
1681                         return null;
1682 #endif
1683                 }
1684
1685                 public static void VerifyModulesClsCompliance ()
1686                 {
1687                         Module[] modules = RootNamespace.Global.Modules;
1688                         if (modules == null)
1689                                 return;
1690
1691                         // The first module is generated assembly
1692                         for (int i = 1; i < modules.Length; ++i) {
1693                                 Module module = modules [i];
1694                                 if (!IsClsCompliant (module)) {
1695                                         Report.Error (3013, "Added modules must be marked with the CLSCompliant attribute " +
1696                                                       "to match the assembly", module.Name);
1697                                         return;
1698                                 }
1699                         }
1700                 }
1701
1702                 public static Type GetImportedIgnoreCaseClsType (string name)
1703                 {
1704                         foreach (Assembly a in RootNamespace.Global.Assemblies) {
1705                                 Type t = a.GetType (name, false, true);
1706                                 if (t == null)
1707                                         continue;
1708
1709                                 if (IsClsCompliant (t))
1710                                         return t;
1711                         }
1712                         return null;
1713                 }
1714
1715                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1716                 {
1717                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1718                         if (CompliantAttribute.Length == 0)
1719                                 return false;
1720
1721                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1722                 }
1723
1724                 static bool AnalyzeTypeCompliance (Type type)
1725                 {
1726                         type = TypeManager.DropGenericTypeArguments (type);
1727                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1728                         if (ds != null) {
1729                                 return ds.IsClsComplianceRequired ();
1730                         }
1731
1732                         if (type.IsGenericParameter)
1733                                 return true;
1734
1735                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1736                         if (CompliantAttribute.Length == 0)
1737                                 return IsClsCompliant (type.Assembly);
1738
1739                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1740                 }
1741
1742                 /// <summary>
1743                 /// Returns instance of ObsoleteAttribute when type is obsolete
1744                 /// </summary>
1745                 public static ObsoleteAttribute GetObsoleteAttribute (Type type)
1746                 {
1747                         object type_obsolete = analyzed_types_obsolete [type];
1748                         if (type_obsolete == FALSE)
1749                                 return null;
1750
1751                         if (type_obsolete != null)
1752                                 return (ObsoleteAttribute)type_obsolete;
1753
1754                         ObsoleteAttribute result = null;
1755                         if (type.IsByRef || type.IsArray || type.IsPointer) {
1756                                 result = GetObsoleteAttribute (TypeManager.GetElementType (type));
1757                         } else if (type.IsGenericParameter || type.IsGenericType)
1758                                 return null;
1759                         else {
1760                                 DeclSpace type_ds = TypeManager.LookupDeclSpace (type);
1761
1762                                 // Type is external, we can get attribute directly
1763                                 if (type_ds == null) {
1764                                         object[] attribute = type.GetCustomAttributes (TypeManager.obsolete_attribute_type, false);
1765                                         if (attribute.Length == 1)
1766                                                 result = (ObsoleteAttribute)attribute [0];
1767                                 } else {
1768                                         // Is null during corlib bootstrap
1769                                         if (TypeManager.obsolete_attribute_type != null)
1770                                                 result = type_ds.GetObsoleteAttribute ();
1771                                 }
1772                         }
1773
1774                         // Cannot use .Add because of corlib bootstrap
1775                         analyzed_types_obsolete [type] = result == null ? FALSE : result;
1776                         return result;
1777                 }
1778
1779                 /// <summary>
1780                 /// Returns instance of ObsoleteAttribute when method is obsolete
1781                 /// </summary>
1782                 public static ObsoleteAttribute GetMethodObsoleteAttribute (MethodBase mb)
1783                 {
1784                         IMethodData mc = TypeManager.GetMethod (mb);
1785                         if (mc != null)
1786                                 return mc.GetObsoleteAttribute ();
1787
1788                         // compiler generated methods are not registered by AddMethod
1789                         if (mb.DeclaringType is TypeBuilder)
1790                                 return null;
1791
1792                         if (mb.IsSpecialName) {
1793                                 PropertyInfo pi = PropertyExpr.AccessorTable [mb] as PropertyInfo;
1794                                 if (pi != null) {
1795                                         if (TypeManager.LookupDeclSpace (pi.DeclaringType) == null)
1796                                                 return GetMemberObsoleteAttribute (pi);
1797
1798                                         return null;
1799                                 }
1800
1801                                 EventInfo ei = EventExpr.AccessorTable [mb] as EventInfo;
1802                                 if (ei != null) {
1803                                         if (TypeManager.LookupDeclSpace (ei.DeclaringType) == null)
1804                                                 return GetMemberObsoleteAttribute (ei);
1805
1806                                         return null;
1807                                 }
1808                         }
1809
1810                         return GetMemberObsoleteAttribute (mb);
1811                 }
1812
1813                 /// <summary>
1814                 /// Returns instance of ObsoleteAttribute when member is obsolete
1815                 /// </summary>
1816                 public static ObsoleteAttribute GetMemberObsoleteAttribute (MemberInfo mi)
1817                 {
1818                         object type_obsolete = analyzed_member_obsolete [mi];
1819                         if (type_obsolete == FALSE)
1820                                 return null;
1821
1822                         if (type_obsolete != null)
1823                                 return (ObsoleteAttribute)type_obsolete;
1824
1825                         if ((mi.DeclaringType is TypeBuilder) || mi.DeclaringType.IsGenericType)
1826                                 return null;
1827
1828                         ObsoleteAttribute oa = System.Attribute.GetCustomAttribute (mi, TypeManager.obsolete_attribute_type, false)
1829                                 as ObsoleteAttribute;
1830                         analyzed_member_obsolete.Add (mi, oa == null ? FALSE : oa);
1831                         return oa;
1832                 }
1833
1834                 /// <summary>
1835                 /// Common method for Obsolete error/warning reporting.
1836                 /// </summary>
1837                 public static void Report_ObsoleteMessage (ObsoleteAttribute oa, string member, Location loc)
1838                 {
1839                         if (oa.IsError) {
1840                                 Report.Error (619, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1841                                 return;
1842                         }
1843
1844                         if (oa.Message == null) {
1845                                 Report.Warning (612, 1, loc, "`{0}' is obsolete", member);
1846                                 return;
1847                         }
1848                         Report.Warning (618, 2, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1849                 }
1850
1851                 public static bool IsConditionalMethodExcluded (MethodBase mb)
1852                 {
1853                         mb = TypeManager.DropGenericMethodArguments (mb);
1854                         if ((mb is MethodBuilder) || (mb is ConstructorBuilder))
1855                                 return false;
1856
1857                         object excluded = analyzed_method_excluded [mb];
1858                         if (excluded != null)
1859                                 return excluded == TRUE ? true : false;
1860
1861                         ConditionalAttribute[] attrs = mb.GetCustomAttributes (TypeManager.conditional_attribute_type, true)
1862                                 as ConditionalAttribute[];
1863                         if (attrs.Length == 0) {
1864                                 analyzed_method_excluded.Add (mb, FALSE);
1865                                 return false;
1866                         }
1867
1868                         foreach (ConditionalAttribute a in attrs) {
1869                                 if (RootContext.AllDefines.Contains (a.ConditionString)) {
1870                                         analyzed_method_excluded.Add (mb, FALSE);
1871                                         return false;
1872                                 }
1873                         }
1874                         analyzed_method_excluded.Add (mb, TRUE);
1875                         return true;
1876                 }
1877
1878                 /// <summary>
1879                 /// Analyzes class whether it has attribute which has ConditionalAttribute
1880                 /// and its condition is not defined.
1881                 /// </summary>
1882                 public static bool IsAttributeExcluded (Type type)
1883                 {
1884                         if (!type.IsClass)
1885                                 return false;
1886
1887                         Class class_decl = TypeManager.LookupDeclSpace (type) as Class;
1888
1889                         // TODO: add caching
1890                         // TODO: merge all Type bases attribute caching to one cache to save memory
1891                         if (class_decl == null) {
1892                                 object[] attributes = type.GetCustomAttributes (TypeManager.conditional_attribute_type, false);
1893                                 foreach (ConditionalAttribute ca in attributes) {
1894                                         if (RootContext.AllDefines.Contains (ca.ConditionString))
1895                                                 return false;
1896                                 }
1897                                 return attributes.Length > 0;
1898                         }
1899
1900                         return class_decl.IsExcluded ();
1901                 }
1902
1903                 public static Type GetCoClassAttribute (Type type)
1904                 {
1905                         TypeContainer tc = TypeManager.LookupInterface (type);
1906                         if (tc == null) {
1907                                 object[] o = type.GetCustomAttributes (TypeManager.coclass_attr_type, false);
1908                                 if (o.Length < 1)
1909                                         return null;
1910                                 return ((System.Runtime.InteropServices.CoClassAttribute)o[0]).CoClass;
1911                         }
1912
1913                         if (tc.OptAttributes == null)
1914                                 return null;
1915
1916                         Attribute a = tc.OptAttributes.Search (TypeManager.coclass_attr_type);
1917                         if (a == null)
1918                                 return null;
1919
1920                         return a.GetCoClassAttributeValue ();
1921                 }
1922         }
1923 }