mcs/mcs/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                         OptAttributes = attrs;
  40                 }
  41
  42                 public Attributes OptAttributes
  43                 {
  44                         get {
  45                                 return attributes;
  46                         }
  47                         set {
  48                                 attributes = value;
  49
  50                                 if (attributes != null) {
  51                                         attributes.AttachTo (this);
  52                                 }
  53                         }
  54                 }
  55
  56                 /// <summary>
  57                 /// Use member-specific procedure to apply attribute @a in @cb to the entity being built in @builder
  58                 /// </summary>
  59                 public abstract void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb);
  60
  61                 /// <summary>
  62                 /// Returns one AttributeTarget for this element.
  63                 /// </summary>
  64                 public abstract AttributeTargets AttributeTargets { get; }
  65
  66                 public abstract IResolveContext ResolveContext { get; }
  67
  68                 public abstract bool IsClsComplianceRequired ();
  69
  70                 /// <summary>
  71                 /// Gets list of valid attribute targets for explicit target declaration.
  72                 /// The first array item is default target. Don't break this rule.
  73                 /// </summary>
  74                 public abstract string[] ValidAttributeTargets { get; }
  75         };
  76
  77         public class Attribute {
  78                 public readonly string ExplicitTarget;
  79                 public AttributeTargets Target;
  80
  81                 // TODO: remove this member
  82                 public readonly string    Name;
  83                 public readonly Expression LeftExpr;
  84                 public readonly string Identifier;
  85
  86                 readonly ArrayList PosArguments;
  87                 readonly ArrayList NamedArguments;
  88
  89                 public readonly Location Location;
  90
  91                 public Type Type;
  92
  93                 bool resolve_error;
  94                 readonly bool nameEscaped;
  95                 Attributable owner;
  96
  97                 static readonly AttributeUsageAttribute DefaultUsageAttribute = new AttributeUsageAttribute (AttributeTargets.All);
  98                 static Assembly orig_sec_assembly;
  99                 public static readonly object[] EmptyObject = new object [0];
 100
 101                 // non-null if named args present after Resolve () is called
 102                 PropertyInfo [] prop_info_arr;
 103                 FieldInfo [] field_info_arr;
 104                 object [] field_values_arr;
 105                 object [] prop_values_arr;
 106                 object [] pos_values;
 107
 108                 static PtrHashtable usage_attr_cache = new PtrHashtable ();
 109
 110                 // Cache for parameter-less attributes
 111                 static PtrHashtable att_cache = new PtrHashtable ();
 112
 113                 public Attribute (string target, Expression left_expr, string identifier, object[] args, Location loc, bool nameEscaped)
 114                 {
 115                         LeftExpr = left_expr;
 116                         Identifier = identifier;
 117                         Name = LeftExpr == null ? identifier : LeftExpr + "." + identifier;
 118                         if (args != null) {
 119                                 PosArguments = (ArrayList)args [0];
 120                                 NamedArguments = (ArrayList)args [1];
 121                         }
 122                         Location = loc;
 123                         ExplicitTarget = target;
 124                         this.nameEscaped = nameEscaped;
 125                 }
 126
 127                 public void AttachTo (Attributable owner)
 128                 {
 129                         this.owner = owner;
 130                 }
 131
 132                 void Error_InvalidNamedArgument (string name)
 133                 {
 134                         Report.Error (617, Location, "`{0}' is not a valid named attribute argument. Named attribute arguments " +
 135                                       "must be fields which are not readonly, static, const or read-write properties which are " +
 136                                       "public and not static",
 137                               name);
 138                 }
 139
 140                 void Error_InvalidNamedAgrumentType (string name)
 141                 {
 142                         Report.Error (655, Location, "`{0}' is not a valid named attribute argument because it is not a valid " +
 143                                       "attribute parameter type", name);
 144                 }
 145
 146                 public static void Error_AttributeArgumentNotValid (Location loc)
 147                 {
 148                         Report.Error (182, loc,
 149                                       "An attribute argument must be a constant expression, typeof " +
 150                                       "expression or array creation expression");
 151                 }
 152
 153                 /// <summary>
 154                 /// This is rather hack. We report many emit attribute error with same error to be compatible with
 155                 /// csc. But because csc has to report them this way because error came from ilasm we needn't.
 156                 /// </summary>
 157                 public void Error_AttributeEmitError (string inner)
 158                 {
 159                         Report.Error (647, Location, "Error during emitting `{0}' attribute. The reason is `{1}'",
 160                                       TypeManager.CSharpName (Type), inner);
 161                 }
 162
 163                 public void Error_InvalidSecurityParent ()
 164                 {
 165                         Error_AttributeEmitError ("it is attached to invalid parent");
 166                 }
 167
 168                 protected virtual TypeExpr ResolveAsTypeTerminal (Expression expr, IResolveContext ec, bool silent)
 169                 {
 170                         return expr.ResolveAsTypeTerminal (ec, silent);
 171                 }
 172
 173                 Type ResolvePossibleAttributeType (string name, bool silent, ref bool is_attr)
 174                 {
 175                         IResolveContext rc = owner.ResolveContext;
 176
 177                         TypeExpr te;
 178                         if (LeftExpr == null) {
 179                                 te = ResolveAsTypeTerminal (new SimpleName (name, Location), rc, silent);
 180                         } else {
 181                                 te = ResolveAsTypeTerminal (new MemberAccess (LeftExpr, name, Location), rc, silent);
 182                         }
 183
 184                         if (te == null)
 185                                 return null;
 186
 187                         Type t = te.Type;
 188                         if (TypeManager.IsSubclassOf (t, TypeManager.attribute_type)) {
 189                                 is_attr = true;
 190                         } else if (!silent) {
 191                                 Report.SymbolRelatedToPreviousError (t);
 192                                 Report.Error (616, Location, "`{0}': is not an attribute class", TypeManager.CSharpName (t));
 193                         }
 194                         return t;
 195                 }
 196
 197                 /// <summary>
 198                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 199                 /// </summary>
 200                 void ResolveAttributeType ()
 201                 {
 202                         bool t1_is_attr = false;
 203                         Type t1 = ResolvePossibleAttributeType (Identifier, true, ref t1_is_attr);
 204
 205                         bool t2_is_attr = false;
 206                         Type t2 = nameEscaped ? null :
 207                                 ResolvePossibleAttributeType (Identifier + "Attribute", true, ref t2_is_attr);
 208
 209                         if (t1_is_attr && t2_is_attr) {
 210                                 Report.Error (1614, Location, "`{0}' is ambiguous between `{0}' and `{0}Attribute'. " +
 211                                               "Use either `@{0}' or `{0}Attribute'", GetSignatureForError ());
 212                                 resolve_error = true;
 213                                 return;
 214                         }
 215
 216                         if (t1_is_attr) {
 217                                 Type = t1;
 218                                 return;
 219                         }
 220
 221                         if (t2_is_attr) {
 222                                 Type = t2;
 223                                 return;
 224                         }
 225
 226                         if (t1 == null && t2 == null)
 227                                 ResolvePossibleAttributeType (Identifier, false, ref t1_is_attr);
 228                         if (t1 != null)
 229                                 ResolvePossibleAttributeType (Identifier, false, ref t1_is_attr);
 230                         if (t2 != null)
 231                                 ResolvePossibleAttributeType (Identifier + "Attribute", false, ref t2_is_attr);
 232
 233                         resolve_error = true;
 234                 }
 235
 236                 public virtual Type ResolveType ()
 237                 {
 238                         if (Type == null && !resolve_error)
 239                                 ResolveAttributeType ();
 240                         return Type;
 241                 }
 242
 243                 public string GetSignatureForError ()
 244                 {
 245                         if (Type != null)
 246                                 return TypeManager.CSharpName (Type);
 247
 248                         return LeftExpr == null ? Identifier : LeftExpr.GetSignatureForError () + "." + Identifier;
 249                 }
 250
 251                 bool IsValidArgumentType (Type t)
 252                 {
 253                         if (t.IsArray)
 254                                 t = t.GetElementType ();
 255
 256                         return TypeManager.IsPrimitiveType (t) ||
 257                                 TypeManager.IsEnumType (t) ||
 258                                 t == TypeManager.string_type ||
 259                                 t == TypeManager.object_type ||
 260                                 t == TypeManager.type_type;
 261                 }
 262
 263                 public CustomAttributeBuilder Resolve ()
 264                 {
 265                         if (resolve_error)
 266                                 return null;
 267
 268                         resolve_error = true;
 269
 270                         if (Type == null) {
 271                                 ResolveAttributeType ();
 272                                 if (Type == null)
 273                                         return null;
 274                         }
 275
 276                         if (Type.IsAbstract) {
 277                                 Report.Error (653, Location, "Cannot apply attribute class `{0}' because it is abstract", GetSignatureForError ());
 278                                 return null;
 279                         }
 280
 281                         ObsoleteAttribute obsolete_attr = AttributeTester.GetObsoleteAttribute (Type);
 282                         if (obsolete_attr != null) {
 283                                 AttributeTester.Report_ObsoleteMessage (obsolete_attr, TypeManager.CSharpName (Type), Location);
 284                         }
 285
 286                         if (PosArguments == null && NamedArguments == null) {
 287                                 object o = att_cache [Type];
 288                                 if (o != null) {
 289                                         resolve_error = false;
 290                                         return (CustomAttributeBuilder)o;
 291                                 }
 292                         }
 293
 294                         EmitContext ec = new EmitContext (owner.ResolveContext, owner.ResolveContext.DeclContainer, owner.ResolveContext.DeclContainer,
 295                                 Location, null, null, owner.ResolveContext.DeclContainer.ModFlags, false);
 296
 297                         ConstructorInfo ctor = ResolveConstructor (ec);
 298                         if (ctor == null)
 299                                 return null;
 300
 301                         CustomAttributeBuilder cb;
 302
 303                         try {
 304                                 if (NamedArguments == null) {
 305                                         cb = new CustomAttributeBuilder (ctor, pos_values);
 306
 307                                         if (pos_values.Length == 0)
 308                                                 att_cache.Add (Type, cb);
 309
 310                                         resolve_error = false;
 311                                         return cb;
 312                                 }
 313
 314                                 if (!ResolveNamedArguments (ec)) {
 315                                         return null;
 316                                 }
 317
 318                                 cb = new CustomAttributeBuilder (ctor, pos_values,
 319                                                 prop_info_arr, prop_values_arr,
 320                                                 field_info_arr, field_values_arr);
 321
 322                                 resolve_error = false;
 323                                 return cb;
 324                         }
 325                         catch (Exception) {
 326                                 Error_AttributeArgumentNotValid (Location);
 327                                 return null;
 328                         }
 329                 }
 330
 331                 protected virtual ConstructorInfo ResolveConstructor (EmitContext ec)
 332                 {
 333                         if (PosArguments != null) {
 334                                 for (int i = 0; i < PosArguments.Count; i++) {
 335                                         Argument a = (Argument) PosArguments [i];
 336
 337                                         if (!a.Resolve (ec, Location))
 338                                                 return null;
 339                                 }
 340                         }
 341
 342                         Expression mg = Expression.MemberLookup (ec.ContainerType,
 343                                 Type, ".ctor", MemberTypes.Constructor,
 344                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 345                                 Location);
 346
 347                         MethodBase constructor = Invocation.OverloadResolve (
 348                                 ec, (MethodGroupExpr) mg, PosArguments, false, Location);
 349
 350                         if (constructor == null)
 351                                 return null;
 352
 353                         ObsoleteAttribute oa = AttributeTester.GetMethodObsoleteAttribute (constructor);
 354                         if (oa != null && !owner.ResolveContext.IsInObsoleteScope) {
 355                                 AttributeTester.Report_ObsoleteMessage (oa, mg.GetSignatureForError (), mg.Location);
 356                         }
 357
 358                         if (PosArguments == null) {
 359                                 pos_values = EmptyObject;
 360                                 return (ConstructorInfo)constructor;
 361                         }
 362
 363                         ParameterData pd = TypeManager.GetParameterData (constructor);
 364
 365                         int pos_arg_count = PosArguments.Count;
 366                         int last_real_param = pd.Count;
 367
 368                         pos_values = new object [pos_arg_count];
 369
 370                         if (pd.HasParams) {
 371                                 // When the params is not filled we need to put one
 372                                 if (last_real_param > pos_arg_count) {
 373                                         object [] new_pos_values = new object [pos_arg_count + 1];
 374                                         pos_values.CopyTo (new_pos_values, 0);
 375                                         new_pos_values [pos_arg_count] = new object [] {} ;
 376                                         pos_values = new_pos_values;
 377                                 }
 378                                 last_real_param--;
 379                         }
 380
 381                         for (int j = 0; j < pos_arg_count; ++j) {
 382                                 Argument a = (Argument) PosArguments [j];
 383
 384                                 if (!a.Expr.GetAttributableValue (out pos_values [j]))
 385                                         return null;
 386
 387                                 if (TypeManager.IsPrimitiveType (a.Type) && a.Type != pos_values [j].GetType ()) {
 388                                         bool fail;
 389                                         // This can happen only for constants in same range
 390                                         pos_values [j] = TypeManager.ChangeType (pos_values [j], a.Type, out fail);
 391                                 }
 392
 393                                 if (j < last_real_param)
 394                                         continue;
 395
 396                                 if (j == last_real_param) {
 397                                         object [] array = new object [pos_arg_count - last_real_param];
 398                                         array [0] = pos_values [j];
 399                                         pos_values [j] = array;
 400                                         continue;
 401                                 }
 402
 403                                 object [] params_array = (object []) pos_values [last_real_param];
 404                                 params_array [j - last_real_param] = pos_values [j];
 405                         }
 406
 407                         // Adjust the size of the pos_values if it had params
 408                         if (last_real_param != pos_arg_count) {
 409                                 object [] new_pos_values = new object [last_real_param + 1];
 410                                 Array.Copy (pos_values, new_pos_values, last_real_param + 1);
 411                                 pos_values = new_pos_values;
 412                         }
 413
 414                         // Here we do the checks which should be done by corlib or by runtime.
 415                         // However Zoltan doesn't like it and every Mono compiler has to do it again.
 416
 417                         if (Type == TypeManager.guid_attr_type) {
 418                                 try {
 419                                         new Guid ((string)pos_values [0]);
 420                                 }
 421                                 catch (Exception e) {
 422                                         Error_AttributeEmitError (e.Message);
 423                                         return null;
 424                                 }
 425                         }
 426
 427                         if (Type == TypeManager.attribute_usage_type && (int)pos_values [0] == 0) {
 428                                 Report.Error (591, Location, "Invalid value for argument to 'System.AttributeUsage' attribute");
 429                                 return null;
 430                         }
 431
 432                         if (Type == TypeManager.methodimpl_attr_type && pos_values.Length == 1 &&
 433                                 pd.ParameterType (0) == TypeManager.short_type &&
 434                                 !System.Enum.IsDefined (typeof (MethodImplOptions), pos_values [0].ToString ())) {
 435                                 Error_AttributeEmitError ("Incorrect argument value.");
 436                                 return null;
 437                         }
 438
 439                         return (ConstructorInfo)constructor;
 440                 }
 441
 442                 protected virtual bool ResolveNamedArguments (EmitContext ec)
 443                 {
 444                         int named_arg_count = NamedArguments.Count;
 445
 446                         ArrayList field_infos = new ArrayList (named_arg_count);
 447                         ArrayList prop_infos  = new ArrayList (named_arg_count);
 448                         ArrayList field_values = new ArrayList (named_arg_count);
 449                         ArrayList prop_values = new ArrayList (named_arg_count);
 450
 451                         ArrayList seen_names = new ArrayList(named_arg_count);
 452
 453                         foreach (DictionaryEntry de in NamedArguments) {
 454                                 string member_name = (string) de.Key;
 455
 456                                 if (seen_names.Contains(member_name)) {
 457                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 458                                         return false;
 459                                 }
 460                                 seen_names.Add(member_name);
 461
 462                                 Argument a = (Argument) de.Value;
 463                                 if (!a.Resolve (ec, Location))
 464                                         return false;
 465
 466                                 Expression member = Expression.MemberLookup (
 467                                         ec.ContainerType, Type, member_name,
 468                                         MemberTypes.Field | MemberTypes.Property,
 469                                         BindingFlags.Public | BindingFlags.Instance,
 470                                         Location);
 471
 472                                 if (member == null) {
 473                                         member = Expression.MemberLookup (ec.ContainerType, Type, member_name,
 474                                                 MemberTypes.Field | MemberTypes.Property, BindingFlags.NonPublic | BindingFlags.Instance,
 475                                                 Location);
 476
 477                                         if (member != null) {
 478                                                 Expression.ErrorIsInaccesible (Location, member.GetSignatureForError ());
 479                                                 return false;
 480                                         }
 481                                 }
 482
 483                                 if (member == null){
 484                                         Report.Error (117, Location, "`{0}' does not contain a definition for `{1}'",
 485                                                       TypeManager.CSharpName (Type), member_name);
 486                                         return false;
 487                                 }
 488
 489                                 if (!(member is PropertyExpr || member is FieldExpr)) {
 490                                         Error_InvalidNamedArgument (member_name);
 491                                         return false;
 492                                 }
 493
 494                                 ObsoleteAttribute obsolete_attr;
 495
 496                                 if (member is PropertyExpr) {
 497                                         PropertyInfo pi = ((PropertyExpr) member).PropertyInfo;
 498
 499                                         if (!pi.CanWrite || !pi.CanRead) {
 500                                                 Report.SymbolRelatedToPreviousError (pi);
 501                                                 Error_InvalidNamedArgument (member_name);
 502                                                 return false;
 503                                         }
 504
 505                                         if (!IsValidArgumentType (pi.PropertyType)) {
 506                                                 Report.SymbolRelatedToPreviousError (pi);
 507                                                 Error_InvalidNamedAgrumentType (member_name);
 508                                                 return false;
 509                                         }
 510
 511                                         Expression e = Convert.ImplicitConversionRequired (ec, a.Expr, pi.PropertyType, a.Expr.Location);
 512                                         if (e == null)
 513                                                 return false;
 514
 515                                         object value;
 516                                         if (!e.GetAttributableValue (out value))
 517                                                 return false;
 518
 519                                         PropertyBase pb = TypeManager.GetProperty (pi);
 520                                         if (pb != null)
 521                                                 obsolete_attr = pb.GetObsoleteAttribute ();
 522                                         else
 523                                                 obsolete_attr = AttributeTester.GetMemberObsoleteAttribute (pi);
 524
 525                                         prop_values.Add (value);
 526                                         prop_infos.Add (pi);
 527
 528                                 } else {
 529                                         FieldInfo fi = ((FieldExpr) member).FieldInfo;
 530
 531                                         if (fi.IsInitOnly) {
 532                                                 Error_InvalidNamedArgument (member_name);
 533                                                 return false;
 534                                         }
 535
 536                                         if (!IsValidArgumentType (fi.FieldType)) {
 537                                                 Report.SymbolRelatedToPreviousError (fi);
 538                                                 Error_InvalidNamedAgrumentType (member_name);
 539                                                 return false;
 540                                         }
 541
 542                                         Expression e = Convert.ImplicitConversionRequired (ec, a.Expr, fi.FieldType, a.Expr.Location);
 543                                         if (e == null)
 544                                                 return false;
 545
 546                                         object value;
 547                                         if (!e.GetAttributableValue (out value))
 548                                                 return false;
 549
 550                                         FieldBase fb = TypeManager.GetField (fi);
 551                                         if (fb != null)
 552                                                 obsolete_attr = fb.GetObsoleteAttribute ();
 553                                         else
 554                                                 obsolete_attr = AttributeTester.GetMemberObsoleteAttribute (fi);
 555
 556                                         field_values.Add (value);
 557                                         field_infos.Add (fi);
 558                                 }
 559
 560                                 if (obsolete_attr != null && !owner.ResolveContext.IsInObsoleteScope)
 561                                         AttributeTester.Report_ObsoleteMessage (obsolete_attr, member.GetSignatureForError (), member.Location);
 562                         }
 563
 564                         prop_info_arr = new PropertyInfo [prop_infos.Count];
 565                         field_info_arr = new FieldInfo [field_infos.Count];
 566                         field_values_arr = new object [field_values.Count];
 567                         prop_values_arr = new object [prop_values.Count];
 568
 569                         field_infos.CopyTo  (field_info_arr, 0);
 570                         field_values.CopyTo (field_values_arr, 0);
 571
 572                         prop_values.CopyTo  (prop_values_arr, 0);
 573                         prop_infos.CopyTo   (prop_info_arr, 0);
 574
 575                         return true;
 576                 }
 577
 578                 /// <summary>
 579                 ///   Get a string containing a list of valid targets for the attribute 'attr'
 580                 /// </summary>
 581                 public string GetValidTargets ()
 582                 {
 583                         StringBuilder sb = new StringBuilder ();
 584                         AttributeTargets targets = GetAttributeUsage ().ValidOn;
 585
 586                         if ((targets & AttributeTargets.Assembly) != 0)
 587                                 sb.Append ("assembly, ");
 588
 589                         if ((targets & AttributeTargets.Module) != 0)
 590                                 sb.Append ("module, ");
 591
 592                         if ((targets & AttributeTargets.Class) != 0)
 593                                 sb.Append ("class, ");
 594
 595                         if ((targets & AttributeTargets.Struct) != 0)
 596                                 sb.Append ("struct, ");
 597
 598                         if ((targets & AttributeTargets.Enum) != 0)
 599                                 sb.Append ("enum, ");
 600
 601                         if ((targets & AttributeTargets.Constructor) != 0)
 602                                 sb.Append ("constructor, ");
 603
 604                         if ((targets & AttributeTargets.Method) != 0)
 605                                 sb.Append ("method, ");
 606
 607                         if ((targets & AttributeTargets.Property) != 0)
 608                                 sb.Append ("property, indexer, ");
 609
 610                         if ((targets & AttributeTargets.Field) != 0)
 611                                 sb.Append ("field, ");
 612
 613                         if ((targets & AttributeTargets.Event) != 0)
 614                                 sb.Append ("event, ");
 615
 616                         if ((targets & AttributeTargets.Interface) != 0)
 617                                 sb.Append ("interface, ");
 618
 619                         if ((targets & AttributeTargets.Parameter) != 0)
 620                                 sb.Append ("parameter, ");
 621
 622                         if ((targets & AttributeTargets.Delegate) != 0)
 623                                 sb.Append ("delegate, ");
 624
 625                         if ((targets & AttributeTargets.ReturnValue) != 0)
 626                                 sb.Append ("return, ");
 627
 628 #if NET_2_0
 629                         if ((targets & AttributeTargets.GenericParameter) != 0)
 630                                 sb.Append ("type parameter, ");
 631 #endif
 632                         return sb.Remove (sb.Length - 2, 2).ToString ();
 633                 }
 634
 635                 /// <summary>
 636                 /// Returns AttributeUsage attribute for this type
 637                 /// </summary>
 638                 AttributeUsageAttribute GetAttributeUsage ()
 639                 {
 640                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 641                         if (ua != null)
 642                                 return ua;
 643
 644                         Class attr_class = TypeManager.LookupClass (Type);
 645
 646                         if (attr_class == null) {
 647                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 648                                 ua = (AttributeUsageAttribute)usage_attr [0];
 649                                 usage_attr_cache.Add (Type, ua);
 650                                 return ua;
 651                         }
 652
 653                         Attribute a = attr_class.OptAttributes == null
 654                                 ? null
 655                                 : attr_class.OptAttributes.Search (TypeManager.attribute_usage_type);
 656
 657                         ua = a == null
 658                                 ? DefaultUsageAttribute
 659                                 : a.GetAttributeUsageAttribute ();
 660
 661                         usage_attr_cache.Add (Type, ua);
 662                         return ua;
 663                 }
 664
 665                 AttributeUsageAttribute GetAttributeUsageAttribute ()
 666                 {
 667                         if (pos_values == null)
 668                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 669                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 670                                 Resolve ();
 671
 672                         if (resolve_error)
 673                                 return DefaultUsageAttribute;
 674
 675                         AttributeUsageAttribute usage_attribute = new AttributeUsageAttribute ((AttributeTargets)pos_values [0]);
 676
 677                         object field = GetPropertyValue ("AllowMultiple");
 678                         if (field != null)
 679                                 usage_attribute.AllowMultiple = (bool)field;
 680
 681                         field = GetPropertyValue ("Inherited");
 682                         if (field != null)
 683                                 usage_attribute.Inherited = (bool)field;
 684
 685                         return usage_attribute;
 686                 }
 687
 688                 /// <summary>
 689                 /// Returns custom name of indexer
 690                 /// </summary>
 691                 public string GetIndexerAttributeValue ()
 692                 {
 693                         if (pos_values == null)
 694                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 695                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 696                                 Resolve ();
 697
 698                         if (resolve_error)
 699                                 return null;
 700
 701                         return pos_values [0] as string;
 702                 }
 703
 704                 /// <summary>
 705                 /// Returns condition of ConditionalAttribute
 706                 /// </summary>
 707                 public string GetConditionalAttributeValue ()
 708                 {
 709                         if (pos_values == null)
 710                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 711                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 712                                 Resolve ();
 713
 714                         if (resolve_error)
 715                                 return null;
 716
 717                         return (string)pos_values [0];
 718                 }
 719
 720                 /// <summary>
 721                 /// Creates the instance of ObsoleteAttribute from this attribute instance
 722                 /// </summary>
 723                 public ObsoleteAttribute GetObsoleteAttribute ()
 724                 {
 725                         if (pos_values == null)
 726                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 727                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 728                                 Resolve ();
 729
 730                         if (resolve_error)
 731                                 return null;
 732
 733                         if (pos_values == null || pos_values.Length == 0)
 734                                 return new ObsoleteAttribute ();
 735
 736                         if (pos_values.Length == 1)
 737                                 return new ObsoleteAttribute ((string)pos_values [0]);
 738
 739                         return new ObsoleteAttribute ((string)pos_values [0], (bool)pos_values [1]);
 740                 }
 741
 742                 /// <summary>
 743                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 744                 /// before ApplyAttribute. We need to resolve the arguments.
 745                 /// This situation occurs when class deps is differs from Emit order.
 746                 /// </summary>
 747                 public bool GetClsCompliantAttributeValue ()
 748                 {
 749                         if (pos_values == null)
 750                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 751                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 752                                 Resolve ();
 753
 754                         if (resolve_error)
 755                                 return false;
 756
 757                         return (bool)pos_values [0];
 758                 }
 759
 760                 public Type GetCoClassAttributeValue ()
 761                 {
 762                         if (pos_values == null)
 763                                 Resolve ();
 764
 765                         if (resolve_error)
 766                                 return null;
 767
 768                         return (Type)pos_values [0];
 769                 }
 770
 771                 public bool CheckTarget ()
 772                 {
 773                         string[] valid_targets = owner.ValidAttributeTargets;
 774                         if (ExplicitTarget == null || ExplicitTarget == valid_targets [0]) {
 775                                 Target = owner.AttributeTargets;
 776                                 return true;
 777                         }
 778
 779                         // TODO: we can skip the first item
 780                         if (((IList) valid_targets).Contains (ExplicitTarget)) {
 781                                 switch (ExplicitTarget) {
 782                                         case "return": Target = AttributeTargets.ReturnValue; return true;
 783                                         case "param": Target = AttributeTargets.Parameter; return true;
 784                                         case "field": Target = AttributeTargets.Field; return true;
 785                                         case "method": Target = AttributeTargets.Method; return true;
 786                                         case "property": Target = AttributeTargets.Property; return true;
 787                                 }
 788                                 throw new InternalErrorException ("Unknown explicit target: " + ExplicitTarget);
 789                         }
 790
 791                         StringBuilder sb = new StringBuilder ();
 792                         foreach (string s in valid_targets) {
 793                                 sb.Append (s);
 794                                 sb.Append (", ");
 795                         }
 796                         sb.Remove (sb.Length - 2, 2);
 797                         Report.Error (657, Location, "`{0}' is not a valid attribute location for this declaration. " +
 798                                 "Valid attribute locations for this declaration are `{1}'", ExplicitTarget, sb.ToString ());
 799                         return false;
 800                 }
 801
 802                 /// <summary>
 803                 /// Tests permitted SecurityAction for assembly or other types
 804                 /// </summary>
 805                 public bool CheckSecurityActionValidity (bool for_assembly)
 806                 {
 807                         SecurityAction action  = GetSecurityActionValue ();
 808
 809                         if ((action == SecurityAction.RequestMinimum || action == SecurityAction.RequestOptional ||
 810                              action == SecurityAction.RequestRefuse) && for_assembly)
 811                                 return true;
 812
 813                         if (!for_assembly) {
 814                                 if (action < SecurityAction.Demand || action > SecurityAction.InheritanceDemand) {
 815                                         Error_AttributeEmitError ("SecurityAction is out of range");
 816                                         return false;
 817                                 }
 818
 819                                 if ((action != SecurityAction.RequestMinimum && action != SecurityAction.RequestOptional &&
 820                                      action != SecurityAction.RequestRefuse) && !for_assembly)
 821                                         return true;
 822                         }
 823
 824                         Error_AttributeEmitError (String.Concat ("SecurityAction `", action, "' is not valid for this declaration"));
 825                         return false;
 826                 }
 827
 828                 System.Security.Permissions.SecurityAction GetSecurityActionValue ()
 829                 {
 830                         return (SecurityAction)pos_values [0];
 831                 }
 832
 833                 /// <summary>
 834                 /// Creates instance of SecurityAttribute class and add result of CreatePermission method to permission table.
 835                 /// </summary>
 836                 /// <returns></returns>
 837                 public void ExtractSecurityPermissionSet (ListDictionary permissions)
 838                 {
 839                         Type orig_assembly_type = null;
 840
 841                         if (TypeManager.LookupDeclSpace (Type) != null) {
 842                                 if (!RootContext.StdLib) {
 843                                         orig_assembly_type = Type.GetType (Type.FullName);
 844                                 } else {
 845                                         string orig_version_path = Environment.GetEnvironmentVariable ("__SECURITY_BOOTSTRAP_DB");
 846                                         if (orig_version_path == null) {
 847                                                 Error_AttributeEmitError ("security custom attributes can not be referenced from defining assembly");
 848                                                 return;
 849                                         }
 850
 851                                         if (orig_sec_assembly == null) {
 852                                                 string file = Path.Combine (orig_version_path, Driver.OutputFile);
 853                                                 orig_sec_assembly = Assembly.LoadFile (file);
 854                                         }
 855
 856                                         orig_assembly_type = orig_sec_assembly.GetType (Type.FullName, true);
 857                                         if (orig_assembly_type == null) {
 858                                                 Report.Warning (-112, 1, Location, "Self-referenced security attribute `{0}' " +
 859                                                                 "was not found in previous version of assembly");
 860                                                 return;
 861                                         }
 862                                 }
 863                         }
 864
 865                         SecurityAttribute sa;
 866                         // For all non-selfreferencing security attributes we can avoid all hacks
 867                         if (orig_assembly_type == null) {
 868                                 sa = (SecurityAttribute) Activator.CreateInstance (Type, pos_values);
 869
 870                                 if (prop_info_arr != null) {
 871                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 872                                                 PropertyInfo pi = prop_info_arr [i];
 873                                                 pi.SetValue (sa, prop_values_arr [i], null);
 874                                         }
 875                                 }
 876                         } else {
 877                                 // HACK: All security attributes have same ctor syntax
 878                                 sa = (SecurityAttribute) Activator.CreateInstance (orig_assembly_type, new object[] { GetSecurityActionValue () } );
 879
 880                                 // All types are from newly created assembly but for invocation with old one we need to convert them
 881                                 if (prop_info_arr != null) {
 882                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 883                                                 PropertyInfo emited_pi = prop_info_arr [i];
 884                                                 PropertyInfo pi = orig_assembly_type.GetProperty (emited_pi.Name, emited_pi.PropertyType);
 885
 886                                                 object old_instance = pi.PropertyType.IsEnum ?
 887                                                         System.Enum.ToObject (pi.PropertyType, prop_values_arr [i]) :
 888                                                         prop_values_arr [i];
 889
 890                                                 pi.SetValue (sa, old_instance, null);
 891                                         }
 892                                 }
 893                         }
 894
 895                         IPermission perm;
 896                         perm = sa.CreatePermission ();
 897                         SecurityAction action = GetSecurityActionValue ();
 898
 899                         // IS is correct because for corlib we are using an instance from old corlib
 900                         if (!(perm is System.Security.CodeAccessPermission)) {
 901                                 switch (action) {
 902                                         case SecurityAction.Demand:
 903                                                 action = (SecurityAction)13;
 904                                                 break;
 905                                         case SecurityAction.LinkDemand:
 906                                                 action = (SecurityAction)14;
 907                                                 break;
 908                                         case SecurityAction.InheritanceDemand:
 909                                                 action = (SecurityAction)15;
 910                                                 break;
 911                                 }
 912                         }
 913
 914                         PermissionSet ps = (PermissionSet)permissions [action];
 915                         if (ps == null) {
 916                                 if (sa is PermissionSetAttribute)
 917                                         ps = new PermissionSet (sa.Unrestricted ? PermissionState.Unrestricted : PermissionState.None);
 918                                 else
 919                                         ps = new PermissionSet (PermissionState.None);
 920
 921                                 permissions.Add (action, ps);
 922                         } else if (!ps.IsUnrestricted () && (sa is PermissionSetAttribute) && sa.Unrestricted) {
 923                                 ps = ps.Union (new PermissionSet (PermissionState.Unrestricted));
 924                                 permissions [action] = ps;
 925                         }
 926                         ps.AddPermission (perm);
 927                 }
 928
 929                 object GetValue (object value)
 930                 {
 931                         if (value is EnumConstant)
 932                                 return ((EnumConstant) value).GetValue ();
 933                         else
 934                                 return value;
 935                 }
 936
 937                 public object GetPropertyValue (string name)
 938                 {
 939                         if (prop_info_arr == null)
 940                                 return null;
 941
 942                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 943                                 if (prop_info_arr [i].Name == name)
 944                                         return prop_values_arr [i];
 945                         }
 946
 947                         return null;
 948                 }
 949
 950                 object GetFieldValue (string name)
 951                 {
 952                         int i;
 953                         if (field_info_arr == null)
 954                                 return null;
 955                         i = 0;
 956                         foreach (FieldInfo fi in field_info_arr) {
 957                                 if (fi.Name == name)
 958                                         return GetValue (field_values_arr [i]);
 959                                 i++;
 960                         }
 961                         return null;
 962                 }
 963
 964                 //
 965                 // Theoretically, we can get rid of this, since FieldBuilder.SetCustomAttribute()
 966                 // and ParameterBuilder.SetCustomAttribute() are supposed to handle this attribute.
 967                 // However, we can't, since it appears that the .NET 1.1 SRE hangs when given a MarshalAsAttribute.
 968                 //
 969                 public UnmanagedMarshal GetMarshal (Attributable attr)
 970                 {
 971                         UnmanagedType UnmanagedType;
 972                         if (!RootContext.StdLib || pos_values [0].GetType () != typeof (UnmanagedType))
 973                                 UnmanagedType = (UnmanagedType) System.Enum.ToObject (typeof (UnmanagedType), pos_values [0]);
 974                         else
 975                                 UnmanagedType = (UnmanagedType) pos_values [0];
 976
 977                         object value = GetFieldValue ("SizeParamIndex");
 978                         if (value != null && UnmanagedType != UnmanagedType.LPArray) {
 979                                 Error_AttributeEmitError ("SizeParamIndex field is not valid for the specified unmanaged type");
 980                                 return null;
 981                         }
 982
 983                         object o = GetFieldValue ("ArraySubType");
 984                         UnmanagedType array_sub_type = o == null ? (UnmanagedType) 0x50 /* NATIVE_MAX */ : (UnmanagedType) o;
 985
 986                         switch (UnmanagedType) {
 987                         case UnmanagedType.CustomMarshaler: {
 988                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
 989                                         BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
 990                                 if (define_custom == null) {
 991                                         Report.RuntimeMissingSupport (Location, "set marshal info");
 992                                         return null;
 993                                 }
 994
 995                                 object [] args = new object [4];
 996                                 args [0] = GetFieldValue ("MarshalTypeRef");
 997                                 args [1] = GetFieldValue ("MarshalCookie");
 998                                 args [2] = GetFieldValue ("MarshalType");
 999                                 args [3] = Guid.Empty;
1000                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
1001                         }
1002                         case UnmanagedType.LPArray: {
1003                                 object size_const = GetFieldValue ("SizeConst");
1004                                 object size_param_index = GetFieldValue ("SizeParamIndex");
1005
1006                                 if ((size_const != null) || (size_param_index != null)) {
1007                                         MethodInfo define_array = typeof (UnmanagedMarshal).GetMethod ("DefineLPArrayInternal",
1008                                                 BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
1009                                         if (define_array == null) {
1010                                                 Report.RuntimeMissingSupport (Location, "set marshal info");
1011                                                 return null;
1012                                         }
1013
1014                                         object [] args = new object [3];
1015                                         args [0] = array_sub_type;
1016                                         args [1] = size_const == null ? -1 : size_const;
1017                                         args [2] = size_param_index == null ? -1 : size_param_index;
1018                                         return (UnmanagedMarshal) define_array.Invoke (null, args);
1019                                 }
1020                                 else
1021                                         return UnmanagedMarshal.DefineLPArray (array_sub_type);
1022                         }
1023                         case UnmanagedType.SafeArray:
1024                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
1025
1026                         case UnmanagedType.ByValArray:
1027                                 FieldMember fm = attr as FieldMember;
1028                                 if (fm == null) {
1029                                         Error_AttributeEmitError ("Specified unmanaged type is only valid on fields");
1030                                         return null;
1031                                 }
1032                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
1033
1034                         case UnmanagedType.ByValTStr:
1035                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
1036
1037                         default:
1038                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
1039                         }
1040                 }
1041
1042                 public CharSet GetCharSetValue ()
1043                 {
1044                         return (CharSet)System.Enum.Parse (typeof (CharSet), pos_values [0].ToString ());
1045                 }
1046
1047                 public MethodImplOptions GetMethodImplOptions ()
1048                 {
1049                         if (pos_values [0].GetType () != typeof (MethodImplOptions))
1050                                 return (MethodImplOptions)System.Enum.ToObject (typeof (MethodImplOptions), pos_values [0]);
1051                         return (MethodImplOptions)pos_values [0];
1052                 }
1053
1054                 public LayoutKind GetLayoutKindValue ()
1055                 {
1056                         if (!RootContext.StdLib || pos_values [0].GetType () != typeof (LayoutKind))
1057                                 return (LayoutKind)System.Enum.ToObject (typeof (LayoutKind), pos_values [0]);
1058
1059                         return (LayoutKind)pos_values [0];
1060                 }
1061
1062                 public override bool Equals (object obj)
1063                 {
1064                         Attribute a = obj as Attribute;
1065                         if (a == null)
1066                                 return false;
1067
1068                         return Type == a.Type && Target == a.Target;
1069                 }
1070
1071                 public override int GetHashCode ()
1072                 {
1073                         return base.GetHashCode ();
1074                 }
1075
1076                 /// <summary>
1077                 /// Emit attribute for Attributable symbol
1078                 /// </summary>
1079                 public void Emit (ListDictionary allEmitted)
1080                 {
1081                         CustomAttributeBuilder cb = Resolve ();
1082                         if (cb == null)
1083                                 return;
1084
1085                         AttributeUsageAttribute usage_attr = GetAttributeUsage ();
1086                         if ((usage_attr.ValidOn & Target) == 0) {
1087                                 Report.Error (592, Location, "The attribute `{0}' is not valid on this declaration type. " +
1088                                               "It is valid on `{1}' declarations only",
1089                                         GetSignatureForError (), GetValidTargets ());
1090                                 return;
1091                         }
1092
1093                         try {
1094                                 owner.ApplyAttributeBuilder (this, cb);
1095                         }
1096                         catch (Exception e) {
1097                                 Error_AttributeEmitError (e.Message);
1098                                 return;
1099                         }
1100
1101                         if (!usage_attr.AllowMultiple && allEmitted != null) {
1102                                 if (allEmitted.Contains (this)) {
1103                                         ArrayList a = allEmitted [this] as ArrayList;
1104                                         if (a == null) {
1105                                                 a = new ArrayList (2);
1106                                                 allEmitted [this] = a;
1107                                         }
1108                                         a.Add (this);
1109                                 } else {
1110                                         allEmitted.Add (this, null);
1111                                 }
1112                         }
1113
1114                         if (!RootContext.VerifyClsCompliance)
1115                                 return;
1116
1117                         // Here we are testing attribute arguments for array usage (error 3016)
1118                         if (owner.IsClsComplianceRequired ()) {
1119                                 if (PosArguments != null) {
1120                                         foreach (Argument arg in PosArguments) {
1121                                                 // Type is undefined (was error 246)
1122                                                 if (arg.Type == null)
1123                                                         return;
1124
1125                                                 if (arg.Type.IsArray) {
1126                                                         Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1127                                                         return;
1128                                                 }
1129                                         }
1130                                 }
1131
1132                                 if (NamedArguments == null)
1133                                         return;
1134
1135                                 foreach (DictionaryEntry de in NamedArguments) {
1136                                         Argument arg  = (Argument) de.Value;
1137
1138                                         // Type is undefined (was error 246)
1139                                         if (arg.Type == null)
1140                                                 return;
1141
1142                                         if (arg.Type.IsArray) {
1143                                                 Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1144                                                 return;
1145                                         }
1146                                 }
1147                         }
1148                 }
1149
1150                 public MethodBuilder DefinePInvokeMethod (TypeBuilder builder, string name,
1151                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
1152                 {
1153                         if (pos_values == null)
1154                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
1155                                 // But because a lot of attribute class code must be rewritten will be better to wait...
1156                                 Resolve ();
1157
1158                         if (resolve_error)
1159                                 return null;
1160
1161                         string dll_name = (string)pos_values [0];
1162
1163                         // Default settings
1164                         CallingConvention cc = CallingConvention.Winapi;
1165                         CharSet charset = CodeGen.Module.DefaultCharSet;
1166                         bool preserve_sig = true;
1167                         string entry_point = name;
1168                         bool best_fit_mapping = false;
1169                         bool throw_on_unmappable = false;
1170                         bool exact_spelling = false;
1171                         bool set_last_error = false;
1172
1173                         bool best_fit_mapping_set = false;
1174                         bool throw_on_unmappable_set = false;
1175                         bool exact_spelling_set = false;
1176                         bool set_last_error_set = false;
1177
1178                         MethodInfo set_best_fit = null;
1179                         MethodInfo set_throw_on = null;
1180                         MethodInfo set_exact_spelling = null;
1181                         MethodInfo set_set_last_error = null;
1182
1183                         if (field_info_arr != null) {
1184
1185                                 for (int i = 0; i < field_info_arr.Length; i++) {
1186                                         switch (field_info_arr [i].Name) {
1187                                         case "BestFitMapping":
1188                                                 best_fit_mapping = (bool) field_values_arr [i];
1189                                                 best_fit_mapping_set = true;
1190                                                 break;
1191                                         case "CallingConvention":
1192                                                 cc = (CallingConvention) field_values_arr [i];
1193                                                 break;
1194                                         case "CharSet":
1195                                                 charset = (CharSet) field_values_arr [i];
1196                                                 break;
1197                                         case "EntryPoint":
1198                                                 entry_point = (string) field_values_arr [i];
1199                                                 break;
1200                                         case "ExactSpelling":
1201                                                 exact_spelling = (bool) field_values_arr [i];
1202                                                 exact_spelling_set = true;
1203                                                 break;
1204                                         case "PreserveSig":
1205                                                 preserve_sig = (bool) field_values_arr [i];
1206                                                 break;
1207                                         case "SetLastError":
1208                                                 set_last_error = (bool) field_values_arr [i];
1209                                                 set_last_error_set = true;
1210                                                 break;
1211                                         case "ThrowOnUnmappableChar":
1212                                                 throw_on_unmappable = (bool) field_values_arr [i];
1213                                                 throw_on_unmappable_set = true;
1214                                                 break;
1215                                         default:
1216                                                 throw new InternalErrorException (field_info_arr [i].ToString ());
1217                                         }
1218                                 }
1219                         }
1220
1221                         if (throw_on_unmappable_set || best_fit_mapping_set || exact_spelling_set || set_last_error_set) {
1222                                 set_best_fit = typeof (MethodBuilder).
1223                                         GetMethod ("set_BestFitMapping", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1224                                 set_throw_on = typeof (MethodBuilder).
1225                                         GetMethod ("set_ThrowOnUnmappableChar", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1226                                 set_exact_spelling = typeof (MethodBuilder).
1227                                         GetMethod ("set_ExactSpelling", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1228                                 set_set_last_error = typeof (MethodBuilder).
1229                                         GetMethod ("set_SetLastError", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1230
1231                                 if ((set_best_fit == null) || (set_throw_on == null) ||
1232                                     (set_exact_spelling == null) || (set_set_last_error == null)) {
1233                                         Report.Error (-1, Location,
1234                                                                   "The ThrowOnUnmappableChar, BestFitMapping, SetLastError, " +
1235                                                       "and ExactSpelling attributes can only be emitted when running on the mono runtime.");
1236                                         return null;
1237                                 }
1238                         }
1239
1240                         try {
1241                                 MethodBuilder mb = builder.DefinePInvokeMethod (
1242                                         name, dll_name, entry_point, flags | MethodAttributes.HideBySig | MethodAttributes.PinvokeImpl,
1243                                         CallingConventions.Standard, ret_type, param_types, cc, charset);
1244
1245                                 if (preserve_sig)
1246                                         mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1247
1248                                 if (throw_on_unmappable_set)
1249                                         set_throw_on.Invoke (mb, 0, null, new object [] { throw_on_unmappable }, null);
1250                                 if (best_fit_mapping_set)
1251                                         set_best_fit.Invoke (mb, 0, null, new object [] { best_fit_mapping }, null);
1252                                 if (exact_spelling_set)
1253                                         set_exact_spelling.Invoke  (mb, 0, null, new object [] { exact_spelling }, null);
1254                                 if (set_last_error_set)
1255                                         set_set_last_error.Invoke  (mb, 0, null, new object [] { set_last_error }, null);
1256
1257                                 return mb;
1258                         }
1259                         catch (ArgumentException e) {
1260                                 Error_AttributeEmitError (e.Message);
1261                                 return null;
1262                         }
1263                 }
1264
1265                 private Expression GetValue ()
1266                 {
1267                         if (PosArguments == null || PosArguments.Count < 1)
1268                                 return null;
1269
1270                         return ((Argument) PosArguments [0]).Expr;
1271                 }
1272
1273                 public string GetString ()
1274                 {
1275                         Expression e = GetValue ();
1276                         if (e is StringLiteral)
1277                                 return (e as StringLiteral).Value;
1278                         return null;
1279                 }
1280
1281                 public bool GetBoolean ()
1282                 {
1283                         Expression e = GetValue ();
1284                         if (e is BoolLiteral)
1285                                 return (e as BoolLiteral).Value;
1286                         return false;
1287                 }
1288         }
1289
1290
1291         /// <summary>
1292         /// For global attributes (assembly, module) we need special handling.
1293         /// Attributes can be located in the several files
1294         /// </summary>
1295         public class GlobalAttribute : Attribute
1296         {
1297                 public readonly NamespaceEntry ns;
1298
1299                 public GlobalAttribute (NamespaceEntry ns, string target,
1300                                         Expression left_expr, string identifier, object[] args, Location loc, bool nameEscaped):
1301                         base (target, left_expr, identifier, args, loc, nameEscaped)
1302                 {
1303                         this.ns = ns;
1304                 }
1305
1306                 void Enter ()
1307                 {
1308                         // RootContext.Tree.Types has a single NamespaceEntry which gets overwritten
1309                         // each time a new file is parsed.  However, we need to use the NamespaceEntry
1310                         // in effect where the attribute was used.  Since code elsewhere cannot assume
1311                         // that the NamespaceEntry is right, just overwrite it.
1312                         //
1313                         // Precondition: RootContext.Tree.Types == null
1314
1315                         if (RootContext.Tree.Types.NamespaceEntry != null)
1316                                 throw new InternalErrorException (Location + " non-null NamespaceEntry");
1317
1318                         RootContext.Tree.Types.NamespaceEntry = ns;
1319                 }
1320
1321                 void Leave ()
1322                 {
1323                         RootContext.Tree.Types.NamespaceEntry = null;
1324                 }
1325
1326                 protected override TypeExpr ResolveAsTypeTerminal (Expression expr, IResolveContext ec, bool silent)
1327                 {
1328                         try {
1329                                 Enter ();
1330                                 return base.ResolveAsTypeTerminal (expr, ec, silent);
1331                         }
1332                         finally {
1333                                 Leave ();
1334                         }
1335                 }
1336
1337                 protected override ConstructorInfo ResolveConstructor (EmitContext ec)
1338                 {
1339                         try {
1340                                 Enter ();
1341                                 return base.ResolveConstructor (ec);
1342                         }
1343                         finally {
1344                                 Leave ();
1345                         }
1346                 }
1347
1348                 protected override bool ResolveNamedArguments (EmitContext ec)
1349                 {
1350                         try {
1351                                 Enter ();
1352                                 return base.ResolveNamedArguments (ec);
1353                         }
1354                         finally {
1355                                 Leave ();
1356                         }
1357                 }
1358         }
1359
1360         public class Attributes {
1361                 public readonly ArrayList Attrs;
1362
1363                 public Attributes (Attribute a)
1364                 {
1365                         Attrs = new ArrayList ();
1366                         Attrs.Add (a);
1367                 }
1368
1369                 public Attributes (ArrayList attrs)
1370                 {
1371                         Attrs = attrs;
1372                 }
1373
1374                 public void AddAttributes (ArrayList attrs)
1375                 {
1376                         Attrs.AddRange (attrs);
1377                 }
1378
1379                 public void AttachTo (Attributable attributable)
1380                 {
1381                         foreach (Attribute a in Attrs)
1382                                 a.AttachTo (attributable);
1383                 }
1384
1385                 /// <summary>
1386                 /// Checks whether attribute target is valid for the current element
1387                 /// </summary>
1388                 public bool CheckTargets ()
1389                 {
1390                         foreach (Attribute a in Attrs) {
1391                                 if (!a.CheckTarget ())
1392                                         return false;
1393                         }
1394                         return true;
1395                 }
1396
1397                 public Attribute Search (Type t)
1398                 {
1399                         foreach (Attribute a in Attrs) {
1400                                 if (a.ResolveType () == t)
1401                                         return a;
1402                         }
1403                         return null;
1404                 }
1405
1406                 /// <summary>
1407                 /// Returns all attributes of type 't'. Use it when attribute is AllowMultiple = true
1408                 /// </summary>
1409                 public Attribute[] SearchMulti (Type t)
1410                 {
1411                         ArrayList ar = null;
1412
1413                         foreach (Attribute a in Attrs) {
1414                                 if (a.ResolveType () == t) {
1415                                         if (ar == null)
1416                                                 ar = new ArrayList ();
1417                                         ar.Add (a);
1418                                 }
1419                         }
1420
1421                         return ar == null ? null : ar.ToArray (typeof (Attribute)) as Attribute[];
1422                 }
1423
1424                 public void Emit ()
1425                 {
1426                         CheckTargets ();
1427
1428                         ListDictionary ld = Attrs.Count > 1 ? new ListDictionary () : null;
1429
1430                         foreach (Attribute a in Attrs)
1431                                 a.Emit (ld);
1432
1433                         if (ld == null || ld.Count == 0)
1434                                 return;
1435
1436                         foreach (DictionaryEntry d in ld) {
1437                                 if (d.Value == null)
1438                                         continue;
1439
1440                                 foreach (Attribute collision in (ArrayList)d.Value)
1441                                         Report.SymbolRelatedToPreviousError (collision.Location, "");
1442
1443                                 Attribute a = (Attribute)d.Key;
1444                                 Report.Error (579, a.Location, "The attribute `{0}' cannot be applied multiple times", a.GetSignatureForError ());
1445                         }
1446                 }
1447
1448                 public bool Contains (Type t)
1449                 {
1450                         return Search (t) != null;
1451                 }
1452         }
1453
1454         /// <summary>
1455         /// Helper class for attribute verification routine.
1456         /// </summary>
1457         sealed class AttributeTester
1458         {
1459                 static PtrHashtable analyzed_types = new PtrHashtable ();
1460                 static PtrHashtable analyzed_types_obsolete = new PtrHashtable ();
1461                 static PtrHashtable analyzed_member_obsolete = new PtrHashtable ();
1462                 static PtrHashtable analyzed_method_excluded = new PtrHashtable ();
1463
1464 #if NET_2_0
1465                 static PtrHashtable fixed_buffer_cache = new PtrHashtable ();
1466 #endif
1467
1468                 static object TRUE = new object ();
1469                 static object FALSE = new object ();
1470
1471                 private AttributeTester ()
1472                 {
1473                 }
1474
1475                 public enum Result {
1476                         Ok,
1477                         RefOutArrayError,
1478                         ArrayArrayError
1479                 }
1480
1481                 /// <summary>
1482                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1483                 /// It tests differing only in ref or out, or in array rank.
1484                 /// </summary>
1485                 public static Result AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1486                 {
1487                         if (types_a == null || types_b == null)
1488                                 return Result.Ok;
1489
1490                         if (types_a.Length != types_b.Length)
1491                                 return Result.Ok;
1492
1493                         Result result = Result.Ok;
1494                         for (int i = 0; i < types_b.Length; ++i) {
1495                                 Type aType = types_a [i];
1496                                 Type bType = types_b [i];
1497
1498                                 if (aType.IsArray && bType.IsArray) {
1499                                         Type a_el_type = aType.GetElementType ();
1500                                         Type b_el_type = bType.GetElementType ();
1501                                         if (aType.GetArrayRank () != bType.GetArrayRank () && a_el_type == b_el_type) {
1502                                                 result = Result.RefOutArrayError;
1503                                                 continue;
1504                                         }
1505
1506                                         if (a_el_type.IsArray || b_el_type.IsArray) {
1507                                                 result = Result.ArrayArrayError;
1508                                                 continue;
1509                                         }
1510                                 }
1511
1512                                 Type aBaseType = aType;
1513                                 bool is_either_ref_or_out = false;
1514
1515                                 if (aType.IsByRef || aType.IsPointer) {
1516                                         aBaseType = aType.GetElementType ();
1517                                         is_either_ref_or_out = true;
1518                                 }
1519
1520                                 Type bBaseType = bType;
1521                                 if (bType.IsByRef || bType.IsPointer)
1522                                 {
1523                                         bBaseType = bType.GetElementType ();
1524                                         is_either_ref_or_out = !is_either_ref_or_out;
1525                                 }
1526
1527                                 if (aBaseType != bBaseType)
1528                                         return Result.Ok;
1529
1530                                 if (is_either_ref_or_out)
1531                                         result = Result.RefOutArrayError;
1532                         }
1533                         return result;
1534                 }
1535
1536                 /// <summary>
1537                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1538                 /// </summary>
1539                 public static bool IsClsCompliant (Type type)
1540                 {
1541                         if (type == null)
1542                                 return true;
1543
1544                         object type_compliance = analyzed_types[type];
1545                         if (type_compliance != null)
1546                                 return type_compliance == TRUE;
1547
1548                         if (type.IsPointer) {
1549                                 analyzed_types.Add (type, null);
1550                                 return false;
1551                         }
1552
1553                         bool result;
1554                         if (type.IsArray || type.IsByRef)       {
1555                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1556                         } else {
1557                                 result = AnalyzeTypeCompliance (type);
1558                         }
1559                         analyzed_types.Add (type, result ? TRUE : FALSE);
1560                         return result;
1561                 }
1562
1563                 /// <summary>
1564                 /// Returns IFixedBuffer implementation if field is fixed buffer else null.
1565                 /// </summary>
1566                 public static IFixedBuffer GetFixedBuffer (FieldInfo fi)
1567                 {
1568                         FieldBase fb = TypeManager.GetField (fi);
1569                         if (fb != null) {
1570                                 return fb as IFixedBuffer;
1571                         }
1572
1573 #if NET_2_0
1574                         object o = fixed_buffer_cache [fi];
1575                         if (o == null) {
1576                                 if (System.Attribute.GetCustomAttribute (fi, TypeManager.fixed_buffer_attr_type) == null) {
1577                                         fixed_buffer_cache.Add (fi, FALSE);
1578                                         return null;
1579                                 }
1580
1581                                 IFixedBuffer iff = new FixedFieldExternal (fi);
1582                                 fixed_buffer_cache.Add (fi, iff);
1583                                 return iff;
1584                         }
1585
1586                         if (o == FALSE)
1587                                 return null;
1588
1589                         return (IFixedBuffer)o;
1590 #else
1591                         return null;
1592 #endif
1593                 }
1594
1595                 public static void VerifyModulesClsCompliance ()
1596                 {
1597                         Module[] modules = RootNamespace.Global.Modules;
1598                         if (modules == null)
1599                                 return;
1600
1601                         // The first module is generated assembly
1602                         for (int i = 1; i < modules.Length; ++i) {
1603                                 Module module = modules [i];
1604                                 if (!IsClsCompliant (module)) {
1605                                         Report.Error (3013, "Added modules must be marked with the CLSCompliant attribute " +
1606                                                       "to match the assembly", module.Name);
1607                                         return;
1608                                 }
1609                         }
1610                 }
1611
1612                 public static Type GetImportedIgnoreCaseClsType (string name)
1613                 {
1614                         foreach (Assembly a in RootNamespace.Global.Assemblies) {
1615                                 Type t = a.GetType (name, false, true);
1616                                 if (t == null)
1617                                         continue;
1618
1619                                 if (IsClsCompliant (t))
1620                                         return t;
1621                         }
1622                         return null;
1623                 }
1624
1625                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1626                 {
1627                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1628                         if (CompliantAttribute.Length == 0)
1629                                 return false;
1630
1631                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1632                 }
1633
1634                 static bool AnalyzeTypeCompliance (Type type)
1635                 {
1636                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1637                         if (ds != null) {
1638                                 return ds.IsClsComplianceRequired ();
1639                         }
1640
1641                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1642                         if (CompliantAttribute.Length == 0)
1643                                 return IsClsCompliant (type.Assembly);
1644
1645                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1646                 }
1647
1648                 /// <summary>
1649                 /// Returns instance of ObsoleteAttribute when type is obsolete
1650                 /// </summary>
1651                 public static ObsoleteAttribute GetObsoleteAttribute (Type type)
1652                 {
1653                         object type_obsolete = analyzed_types_obsolete [type];
1654                         if (type_obsolete == FALSE)
1655                                 return null;
1656
1657                         if (type_obsolete != null)
1658                                 return (ObsoleteAttribute)type_obsolete;
1659
1660                         ObsoleteAttribute result = null;
1661                         if (type.IsByRef || type.IsArray || type.IsPointer) {
1662                                 result = GetObsoleteAttribute (TypeManager.GetElementType (type));
1663                         } else {
1664                                 DeclSpace type_ds = TypeManager.LookupDeclSpace (type);
1665
1666                                 // Type is external, we can get attribute directly
1667                                 if (type_ds == null) {
1668                                         object[] attribute = type.GetCustomAttributes (TypeManager.obsolete_attribute_type, false);
1669                                         if (attribute.Length == 1)
1670                                                 result = (ObsoleteAttribute)attribute [0];
1671                                 } else {
1672                                         // Is null during corlib bootstrap
1673                                         if (TypeManager.obsolete_attribute_type != null)
1674                                                 result = type_ds.GetObsoleteAttribute ();
1675                                 }
1676                         }
1677
1678                         // Cannot use .Add because of corlib bootstrap
1679                         analyzed_types_obsolete [type] = result == null ? FALSE : result;
1680                         return result;
1681                 }
1682
1683                 /// <summary>
1684                 /// Returns instance of ObsoleteAttribute when method is obsolete
1685                 /// </summary>
1686                 public static ObsoleteAttribute GetMethodObsoleteAttribute (MethodBase mb)
1687                 {
1688                         IMethodData mc = TypeManager.GetMethod (mb);
1689                         if (mc != null)
1690                                 return mc.GetObsoleteAttribute ();
1691
1692                         // compiler generated methods are not registered by AddMethod
1693                         if (mb.DeclaringType is TypeBuilder)
1694                                 return null;
1695
1696                         if (mb.IsSpecialName) {
1697                                 PropertyInfo pi = PropertyExpr.AccessorTable [mb] as PropertyInfo;
1698                                 if (pi != null) {
1699                                         // FIXME: This is buggy as properties from this assembly are included as well
1700                                         return null;
1701                                         //return GetMemberObsoleteAttribute (pi);
1702                                 }
1703                         }
1704
1705                         return GetMemberObsoleteAttribute (mb);
1706                 }
1707
1708                 /// <summary>
1709                 /// Returns instance of ObsoleteAttribute when member is obsolete
1710                 /// </summary>
1711                 public static ObsoleteAttribute GetMemberObsoleteAttribute (MemberInfo mi)
1712                 {
1713                         object type_obsolete = analyzed_member_obsolete [mi];
1714                         if (type_obsolete == FALSE)
1715                                 return null;
1716
1717                         if (type_obsolete != null)
1718                                 return (ObsoleteAttribute)type_obsolete;
1719
1720                         ObsoleteAttribute oa = System.Attribute.GetCustomAttribute (mi, TypeManager.obsolete_attribute_type, false)
1721                                 as ObsoleteAttribute;
1722                         analyzed_member_obsolete.Add (mi, oa == null ? FALSE : oa);
1723                         return oa;
1724                 }
1725
1726                 /// <summary>
1727                 /// Common method for Obsolete error/warning reporting.
1728                 /// </summary>
1729                 public static void Report_ObsoleteMessage (ObsoleteAttribute oa, string member, Location loc)
1730                 {
1731                         if (oa.IsError) {
1732                                 Report.Error (619, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1733                                 return;
1734                         }
1735
1736                         if (oa.Message == null) {
1737                                 Report.Warning (612, 1, loc, "`{0}' is obsolete", member);
1738                                 return;
1739                         }
1740                         Report.Warning (618, 2, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1741                 }
1742
1743                 public static bool IsConditionalMethodExcluded (MethodBase mb)
1744                 {
1745                         object excluded = analyzed_method_excluded [mb];
1746                         if (excluded != null)
1747                                 return excluded == TRUE ? true : false;
1748
1749                         ConditionalAttribute[] attrs = mb.GetCustomAttributes (TypeManager.conditional_attribute_type, true)
1750                                 as ConditionalAttribute[];
1751                         if (attrs.Length == 0) {
1752                                 analyzed_method_excluded.Add (mb, FALSE);
1753                                 return false;
1754                         }
1755
1756                         foreach (ConditionalAttribute a in attrs) {
1757                                 if (RootContext.AllDefines.Contains (a.ConditionString)) {
1758                                         analyzed_method_excluded.Add (mb, FALSE);
1759                                         return false;
1760                                 }
1761                         }
1762                         analyzed_method_excluded.Add (mb, TRUE);
1763                         return true;
1764                 }
1765
1766                 /// <summary>
1767                 /// Analyzes class whether it has attribute which has ConditionalAttribute
1768                 /// and its condition is not defined.
1769                 /// </summary>
1770                 public static bool IsAttributeExcluded (Type type)
1771                 {
1772                         if (!type.IsClass)
1773                                 return false;
1774
1775                         Class class_decl = TypeManager.LookupDeclSpace (type) as Class;
1776
1777                         // TODO: add caching
1778                         // TODO: merge all Type bases attribute caching to one cache to save memory
1779                         if (class_decl == null) {
1780                                 object[] attributes = type.GetCustomAttributes (TypeManager.conditional_attribute_type, false);
1781                                 foreach (ConditionalAttribute ca in attributes) {
1782                                         if (RootContext.AllDefines.Contains (ca.ConditionString))
1783                                                 return false;
1784                                 }
1785                                 return attributes.Length > 0;
1786                         }
1787
1788                         return class_decl.IsExcluded ();
1789                 }
1790
1791                 public static Type GetCoClassAttribute (Type type)
1792                 {
1793                         TypeContainer tc = TypeManager.LookupInterface (type);
1794                         if (tc == null) {
1795                                 object[] o = type.GetCustomAttributes (TypeManager.coclass_attr_type, false);
1796                                 if (o.Length < 1)
1797                                         return null;
1798                                 return ((System.Runtime.InteropServices.CoClassAttribute)o[0]).CoClass;
1799                         }
1800
1801                         if (tc.OptAttributes == null)
1802                                 return null;
1803
1804                         Attribute a = tc.OptAttributes.Search (TypeManager.coclass_attr_type);
1805                         if (a == null)
1806                                 return null;
1807
1808                         return a.GetCoClassAttributeValue ();
1809                 }
1810         }
1811 }