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                 public readonly ArrayList Arguments;
  87
  88                 public readonly Location Location;
  89
  90                 public Type Type;
  91
  92                 bool resolve_error;
  93                 readonly bool nameEscaped;
  94                 Attributable owner;
  95
  96                 static AttributeUsageAttribute DefaultUsageAttribute = new AttributeUsageAttribute (AttributeTargets.All);
  97                 static Assembly orig_sec_assembly;
  98
  99                 // non-null if named args present after Resolve () is called
 100                 PropertyInfo [] prop_info_arr;
 101                 FieldInfo [] field_info_arr;
 102                 object [] field_values_arr;
 103                 object [] prop_values_arr;
 104                 object [] pos_values;
 105
 106                 static PtrHashtable usage_attr_cache = new PtrHashtable ();
 107
 108                 public Attribute (string target, Expression left_expr, string identifier, ArrayList args, Location loc, bool nameEscaped)
 109                 {
 110                         LeftExpr = left_expr;
 111                         Identifier = identifier;
 112                         Name = LeftExpr == null ? identifier : LeftExpr + "." + identifier;
 113                         Arguments = args;
 114                         Location = loc;
 115                         ExplicitTarget = target;
 116                         this.nameEscaped = nameEscaped;
 117                 }
 118
 119                 public void AttachTo (Attributable owner)
 120                 {
 121                         this.owner = owner;
 122                 }
 123
 124                 void Error_InvalidNamedArgument (string name)
 125                 {
 126                         Report.Error (617, Location, "`{0}' is not a valid named attribute argument. Named attribute arguments " +
 127                                       "must be fields which are not readonly, static, const or read-write properties which are " +
 128                                       "public and not static",
 129                               name);
 130                 }
 131
 132                 void Error_InvalidNamedAgrumentType (string name)
 133                 {
 134                         Report.Error (655, Location, "`{0}' is not a valid named attribute argument because it is not a valid " +
 135                                       "attribute parameter type", name);
 136                 }
 137
 138                 static void Error_AttributeArgumentNotValid (string extra, Location loc)
 139                 {
 140                         Report.Error (182, loc,
 141                                       "An attribute argument must be a constant expression, typeof " +
 142                                       "expression or array creation expression" + extra);
 143                 }
 144
 145                 static void Error_AttributeArgumentNotValid (Location loc)
 146                 {
 147                         Error_AttributeArgumentNotValid ("", loc);
 148                 }
 149
 150
 151                 /// <summary>
 152                 /// This is rather hack. We report many emit attribute error with same error to be compatible with
 153                 /// csc. But because csc has to report them this way because error came from ilasm we needn't.
 154                 /// </summary>
 155                 public void Error_AttributeEmitError (string inner)
 156                 {
 157                         Report.Error (647, Location, "Error during emitting `{0}' attribute. The reason is `{1}'",
 158                                       TypeManager.CSharpName (Type), inner);
 159                 }
 160
 161                 public void Error_InvalidSecurityParent ()
 162                 {
 163                         Error_AttributeEmitError ("it is attached to invalid parent");
 164                 }
 165
 166                 protected virtual FullNamedExpression ResolveAsTypeTerminal (Expression expr, IResolveContext ec, bool silent)
 167                 {
 168                         return expr.ResolveAsTypeTerminal (ec, silent);
 169                 }
 170
 171                 protected virtual FullNamedExpression ResolveAsTypeStep (Expression expr, IResolveContext ec, bool silent)
 172                 {
 173                         return expr.ResolveAsTypeStep (ec, silent);
 174                 }
 175
 176                 Type ResolvePossibleAttributeType (string name, bool silent, ref bool is_attr)
 177                 {
 178                         IResolveContext rc = owner.ResolveContext;
 179
 180                         FullNamedExpression fn;
 181                         if (LeftExpr == null) {
 182                                 fn = ResolveAsTypeTerminal (new SimpleName (name, Location), rc, silent);
 183                         } else {
 184                                 fn = ResolveAsTypeStep (LeftExpr, rc, silent);
 185                                 if (fn == null)
 186                                         return null;
 187                                 fn = new MemberAccess (fn, name, Location).ResolveAsTypeTerminal (rc, silent);
 188                         }
 189
 190                         TypeExpr te = fn as TypeExpr;
 191                         if (te == null)
 192                                 return null;
 193
 194                         Type t = te.Type;
 195                         if (TypeManager.IsSubclassOf (t, TypeManager.attribute_type)) {
 196                                 is_attr = true;
 197                         } else if (!silent) {
 198                                 Report.SymbolRelatedToPreviousError (t);
 199                                 Report.Error (616, Location, "`{0}': is not an attribute class", TypeManager.CSharpName (t));
 200                         }
 201                         return t;
 202                 }
 203
 204                 /// <summary>
 205                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 206                 /// </summary>
 207                 void ResolveAttributeType ()
 208                 {
 209                         bool t1_is_attr = false;
 210                         Type t1 = ResolvePossibleAttributeType (Identifier, true, ref t1_is_attr);
 211
 212                         bool t2_is_attr = false;
 213                         Type t2 = nameEscaped ? null :
 214                                 ResolvePossibleAttributeType (Identifier + "Attribute", true, ref t2_is_attr);
 215
 216                         if (t1_is_attr && t2_is_attr) {
 217                                 Report.Error (1614, Location, "`{0}' is ambiguous between `{0}' and `{0}Attribute'. " +
 218                                               "Use either `@{0}' or `{0}Attribute'", GetSignatureForError ());
 219                                 resolve_error = true;
 220                                 return;
 221                         }
 222
 223                         if (t1_is_attr) {
 224                                 Type = t1;
 225                                 return;
 226                         }
 227
 228                         if (t2_is_attr) {
 229                                 Type = t2;
 230                                 return;
 231                         }
 232
 233                         if (t1 == null && t2 == null)
 234                                 ResolvePossibleAttributeType (Identifier, false, ref t1_is_attr);
 235                         if (t1 != null)
 236                                 ResolvePossibleAttributeType (Identifier, false, ref t1_is_attr);
 237                         if (t2 != null)
 238                                 ResolvePossibleAttributeType (Identifier + "Attribute", false, ref t2_is_attr);
 239
 240                         resolve_error = true;
 241                 }
 242
 243                 public virtual Type ResolveType ()
 244                 {
 245                         if (Type == null && !resolve_error)
 246                                 ResolveAttributeType ();
 247                         return Type;
 248                 }
 249
 250                 public string GetSignatureForError ()
 251                 {
 252                         if (Type != null)
 253                                 return TypeManager.CSharpName (Type);
 254
 255                         return LeftExpr == null ? Identifier : LeftExpr.GetSignatureForError () + "." + Identifier;
 256                 }
 257
 258                 //
 259                 // Given an expression, if the expression is a valid attribute-argument-expression
 260                 // returns an object that can be used to encode it, or null on failure.
 261                 //
 262                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, Type arg_type, out object result)
 263                 {
 264                         Constant constant = e as Constant;
 265                         if (constant != null) {
 266                                 constant = constant.ToType (arg_type, loc);
 267                                 if (constant == null) {
 268                                         result = null;
 269                                         return false;
 270                                 }
 271                                 result = constant.GetTypedValue ();
 272                                 return true;
 273                         } else if (e is TypeOf) {
 274                                 result = ((TypeOf) e).TypeArg;
 275                                 return true;
 276                         } else if (e is ArrayCreation){
 277                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();
 278                                 if (result != null)
 279                                         return true;
 280                         } else if (e is EmptyCast) {
 281                                 Expression child = ((EmptyCast)e).Child;
 282                                 return GetAttributeArgumentExpression (child, loc, child.Type, out result);
 283                         } else if (e is As) {
 284                                 As as_e = (As) e;
 285                                 return GetAttributeArgumentExpression (as_e.Expr, loc, as_e.ProbeType.Type, out result);
 286                         }
 287
 288                         result = null;
 289                         Error_AttributeArgumentNotValid (loc);
 290                         return false;
 291                 }
 292
 293                 bool IsValidArgumentType (Type t)
 294                 {
 295                         if (t.IsArray)
 296                                 t = t.GetElementType ();
 297
 298                         return TypeManager.IsPrimitiveType (t) ||
 299                                 TypeManager.IsEnumType (t) ||
 300                                 t == TypeManager.string_type ||
 301                                 t == TypeManager.object_type ||
 302                                 t == TypeManager.type_type;
 303                 }
 304
 305                 // Cache for parameter-less attributes
 306                 static PtrHashtable att_cache = new PtrHashtable ();
 307
 308                 public CustomAttributeBuilder Resolve ()
 309                 {
 310                         if (resolve_error)
 311                                 return null;
 312
 313                         resolve_error = true;
 314
 315                         if (Type == null) {
 316                                 ResolveAttributeType ();
 317                                 if (Type == null)
 318                                         return null;
 319                         }
 320
 321                         if (Type.IsAbstract) {
 322                                 Report.Error (653, Location, "Cannot apply attribute class `{0}' because it is abstract", GetSignatureForError ());
 323                                 return null;
 324                         }
 325
 326                         ObsoleteAttribute obsolete_attr = AttributeTester.GetObsoleteAttribute (Type);
 327                         if (obsolete_attr != null) {
 328                                 AttributeTester.Report_ObsoleteMessage (obsolete_attr, TypeManager.CSharpName (Type), Location);
 329                         }
 330
 331                         if (Arguments == null) {
 332                                 object o = att_cache [Type];
 333                                 if (o != null) {
 334                                         resolve_error = false;
 335                                         return (CustomAttributeBuilder)o;
 336                                 }
 337                         }
 338
 339                         ConstructorInfo ctor = ResolveArguments ();
 340                         if (ctor == null)
 341                                 return null;
 342
 343                         CustomAttributeBuilder cb;
 344
 345                         try {
 346                                 if (prop_info_arr != null || field_info_arr != null) {
 347                                         cb = new CustomAttributeBuilder (
 348                                                 ctor, pos_values,
 349                                                 prop_info_arr, prop_values_arr,
 350                                                 field_info_arr, field_values_arr);
 351                                 } else {
 352                                         cb = new CustomAttributeBuilder (
 353                                                 ctor, pos_values);
 354
 355                                         if (pos_values.Length == 0)
 356                                                 att_cache.Add (Type, cb);
 357                                 }
 358                         }
 359                         catch (Exception) {
 360                                 Error_AttributeArgumentNotValid (Location);
 361                                 return null;
 362                         }
 363
 364                         resolve_error = false;
 365                         return cb;
 366                 }
 367
 368                 protected virtual ConstructorInfo ResolveArguments ()
 369                 {
 370                         // Now we extract the positional and named arguments
 371
 372                         ArrayList pos_args = null;
 373                         ArrayList named_args = null;
 374                         int pos_arg_count = 0;
 375                         int named_arg_count = 0;
 376
 377                         if (Arguments != null) {
 378                                 pos_args = (ArrayList) Arguments [0];
 379                                 if (pos_args != null)
 380                                         pos_arg_count = pos_args.Count;
 381                                 if (Arguments.Count > 1) {
 382                                         named_args = (ArrayList) Arguments [1];
 383                                         named_arg_count = named_args.Count;
 384                                 }
 385                         }
 386
 387                         pos_values = new object [pos_arg_count];
 388
 389                         //
 390                         // First process positional arguments
 391                         //
 392
 393                         EmitContext ec = new EmitContext (owner.ResolveContext, owner.ResolveContext.DeclContainer, owner.ResolveContext.DeclContainer,
 394                                         Location, null, null, owner.ResolveContext.DeclContainer.ModFlags, false);
 395
 396                         int i;
 397                         for (i = 0; i < pos_arg_count; i++) {
 398                                 Argument a = (Argument) pos_args [i];
 399                                 Expression e;
 400
 401                                 if (!a.Resolve (ec, Location))
 402                                         return null;
 403
 404                                 e = a.Expr;
 405
 406                                 object val;
 407                                 if (!GetAttributeArgumentExpression (e, Location, a.Type, out val))
 408                                         return null;
 409
 410                                 pos_values [i] = val;
 411
 412                                 if (i == 0 && Type == TypeManager.attribute_usage_type && (int)val == 0) {
 413                                         Report.Error (591, Location, "Invalid value for argument to 'System.AttributeUsage' attribute");
 414                                         return null;
 415                                 }
 416                         }
 417
 418                         //
 419                         // Now process named arguments
 420                         //
 421
 422                         ArrayList field_infos = null;
 423                         ArrayList prop_infos  = null;
 424                         ArrayList field_values = null;
 425                         ArrayList prop_values = null;
 426                         Hashtable seen_names = null;
 427
 428                         if (named_arg_count > 0) {
 429                                 field_infos = new ArrayList (4);
 430                                 prop_infos  = new ArrayList (4);
 431                                 field_values = new ArrayList (4);
 432                                 prop_values = new ArrayList (4);
 433
 434                                 seen_names = new Hashtable(4);
 435                         }
 436
 437                         for (i = 0; i < named_arg_count; i++) {
 438                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 439                                 string member_name = (string) de.Key;
 440                                 Argument a  = (Argument) de.Value;
 441                                 Expression e;
 442
 443                                 if (seen_names.Contains(member_name)) {
 444                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 445                                         return null;
 446                                 }
 447                                 seen_names.Add(member_name, 1);
 448
 449                                 if (!a.Resolve (ec, Location))
 450                                         return null;
 451
 452                                 Expression member = Expression.MemberLookup (
 453                                         ec.ContainerType, Type, member_name,
 454                                         MemberTypes.Field | MemberTypes.Property,
 455                                         BindingFlags.Public | BindingFlags.Instance,
 456                                         Location);
 457
 458                                 if (member == null) {
 459                                         member = Expression.MemberLookup (ec.ContainerType, Type, member_name,
 460                                                 MemberTypes.Field | MemberTypes.Property, BindingFlags.NonPublic | BindingFlags.Instance,
 461                                                 Location);
 462
 463                                         if (member != null) {
 464                                                 Expression.ErrorIsInaccesible (Location, member.GetSignatureForError ());
 465                                                 return null;
 466                                         }
 467                                 }
 468
 469                                 if (member == null){
 470                                         Report.Error (117, Location, "`{0}' does not contain a definition for `{1}'",
 471                                                       TypeManager.CSharpName (Type), member_name);
 472                                         return null;
 473                                 }
 474
 475                                 if (!(member is PropertyExpr || member is FieldExpr)) {
 476                                         Error_InvalidNamedArgument (member_name);
 477                                         return null;
 478                                 }
 479
 480                                 e = a.Expr;
 481                                 if (member is PropertyExpr) {
 482                                         PropertyExpr pe = (PropertyExpr) member;
 483                                         PropertyInfo pi = pe.PropertyInfo;
 484
 485                                         if (!pi.CanWrite || !pi.CanRead) {
 486                                                 Report.SymbolRelatedToPreviousError (pi);
 487                                                 Error_InvalidNamedArgument (member_name);
 488                                                 return null;
 489                                         }
 490
 491                                         if (!IsValidArgumentType (pi.PropertyType)) {
 492                                                 Report.SymbolRelatedToPreviousError (pi);
 493                                                 Error_InvalidNamedAgrumentType (member_name);
 494                                                 return null;
 495                                         }
 496
 497                                         object value;
 498                                         if (!GetAttributeArgumentExpression (e, Location, pi.PropertyType, out value))
 499                                                 return null;
 500
 501                                         prop_values.Add (value);
 502                                         prop_infos.Add (pi);
 503
 504                                 } else if (member is FieldExpr) {
 505                                         FieldExpr fe = (FieldExpr) member;
 506                                         FieldInfo fi = fe.FieldInfo;
 507
 508                                         if (fi.IsInitOnly) {
 509                                                 Error_InvalidNamedArgument (member_name);
 510                                                 return null;
 511                                         }
 512
 513                                         if (!IsValidArgumentType (fi.FieldType)) {
 514                                                 Report.SymbolRelatedToPreviousError (fi);
 515                                                 Error_InvalidNamedAgrumentType (member_name);
 516                                                 return null;
 517                                         }
 518
 519                                         object value;
 520                                         if (!GetAttributeArgumentExpression (e, Location, fi.FieldType, out value))
 521                                                 return null;
 522
 523                                         field_values.Add (value);
 524                                         field_infos.Add (fi);
 525                                 }
 526                         }
 527
 528                         Expression mg = Expression.MemberLookup (ec.ContainerType,
 529                                 Type, ".ctor", MemberTypes.Constructor,
 530                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 531                                 Location);
 532
 533                         MethodBase constructor = Invocation.OverloadResolve (
 534                                 ec, (MethodGroupExpr) mg, pos_args, false, Location);
 535
 536                         if (constructor == null) {
 537                                 return null;
 538                         }
 539
 540
 541                         // Here we do the checks which should be done by corlib or by runtime.
 542                         // However Zoltan doesn't like it and every Mono compiler has to do it again.
 543
 544                         if (Type == TypeManager.guid_attr_type) {
 545                                 try {
 546                                         new Guid ((string)pos_values [0]);
 547                                 }
 548                                 catch (Exception e) {
 549                                         Error_AttributeEmitError (e.Message);
 550                                         return null;
 551                                 }
 552                         }
 553
 554                         if (Type == TypeManager.methodimpl_attr_type &&
 555                                 pos_values.Length == 1 && ((Argument)pos_args [0]).Type == TypeManager.short_type &&
 556                                 !System.Enum.IsDefined (typeof (MethodImplOptions), pos_values [0])) {
 557                                         Error_AttributeEmitError ("Incorrect argument value.");
 558                                 return null;
 559                         }
 560
 561                         //
 562                         // Now we perform some checks on the positional args as they
 563                         // cannot be null for a constructor which expects a parameter
 564                         // of type object
 565                         //
 566
 567                         ParameterData pd = TypeManager.GetParameterData (constructor);
 568
 569                         int last_real_param = pd.Count;
 570                         if (pd.HasParams) {
 571                                 // When the params is not filled we need to put one
 572                                 if (last_real_param > pos_arg_count) {
 573                                         object [] new_pos_values = new object [pos_arg_count + 1];
 574                                         pos_values.CopyTo (new_pos_values, 0);
 575                                         new_pos_values [pos_arg_count] = new object [] {} ;
 576                                         pos_values = new_pos_values;
 577                                 }
 578                                 last_real_param--;
 579                         }
 580
 581                         for (int j = 0; j < pos_arg_count; ++j) {
 582                                 Argument a = (Argument) pos_args [j];
 583
 584                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {
 585                                         Error_AttributeArgumentNotValid (Location);
 586                                         return null;
 587                                 }
 588
 589                                 object value = pos_values [j];
 590                                 if (value != null && a.Type != value.GetType () && TypeManager.IsPrimitiveType (a.Type)) {
 591                                         bool fail;
 592                                         pos_values [j] = TypeManager.ChangeType (value, a.Type, out fail);
 593                                         if (fail) {
 594                                                 // TODO: Can failed ?
 595                                                 throw new NotImplementedException ();
 596                                         }
 597                                 }
 598
 599                                 if (j < last_real_param)
 600                                         continue;
 601
 602                                 if (j == last_real_param) {
 603                                         object [] array = new object [pos_arg_count - last_real_param];
 604                                         array [0] = pos_values [j];
 605                                         pos_values [j] = array;
 606                                         continue;
 607                                 }
 608
 609                                 object [] params_array = (object []) pos_values [last_real_param];
 610                                 params_array [j - last_real_param] = pos_values [j];
 611                         }
 612
 613                         // Adjust the size of the pos_values if it had params
 614                         if (last_real_param != pos_arg_count) {
 615                                 object [] new_pos_values = new object [last_real_param + 1];
 616                                 Array.Copy (pos_values, new_pos_values, last_real_param + 1);
 617                                 pos_values = new_pos_values;
 618                         }
 619
 620                         if (named_arg_count > 0) {
 621                                 prop_info_arr = new PropertyInfo [prop_infos.Count];
 622                                 field_info_arr = new FieldInfo [field_infos.Count];
 623                                 field_values_arr = new object [field_values.Count];
 624                                 prop_values_arr = new object [prop_values.Count];
 625
 626                                 field_infos.CopyTo  (field_info_arr, 0);
 627                                 field_values.CopyTo (field_values_arr, 0);
 628
 629                                 prop_values.CopyTo  (prop_values_arr, 0);
 630                                 prop_infos.CopyTo   (prop_info_arr, 0);
 631                         }
 632
 633                         return (ConstructorInfo) constructor;
 634                 }
 635
 636                 /// <summary>
 637                 ///   Get a string containing a list of valid targets for the attribute 'attr'
 638                 /// </summary>
 639                 public string GetValidTargets ()
 640                 {
 641                         StringBuilder sb = new StringBuilder ();
 642                         AttributeTargets targets = GetAttributeUsage ().ValidOn;
 643
 644                         if ((targets & AttributeTargets.Assembly) != 0)
 645                                 sb.Append ("assembly, ");
 646
 647                         if ((targets & AttributeTargets.Module) != 0)
 648                                 sb.Append ("module, ");
 649
 650                         if ((targets & AttributeTargets.Class) != 0)
 651                                 sb.Append ("class, ");
 652
 653                         if ((targets & AttributeTargets.Struct) != 0)
 654                                 sb.Append ("struct, ");
 655
 656                         if ((targets & AttributeTargets.Enum) != 0)
 657                                 sb.Append ("enum, ");
 658
 659                         if ((targets & AttributeTargets.Constructor) != 0)
 660                                 sb.Append ("constructor, ");
 661
 662                         if ((targets & AttributeTargets.Method) != 0)
 663                                 sb.Append ("method, ");
 664
 665                         if ((targets & AttributeTargets.Property) != 0)
 666                                 sb.Append ("property, indexer, ");
 667
 668                         if ((targets & AttributeTargets.Field) != 0)
 669                                 sb.Append ("field, ");
 670
 671                         if ((targets & AttributeTargets.Event) != 0)
 672                                 sb.Append ("event, ");
 673
 674                         if ((targets & AttributeTargets.Interface) != 0)
 675                                 sb.Append ("interface, ");
 676
 677                         if ((targets & AttributeTargets.Parameter) != 0)
 678                                 sb.Append ("parameter, ");
 679
 680                         if ((targets & AttributeTargets.Delegate) != 0)
 681                                 sb.Append ("delegate, ");
 682
 683                         if ((targets & AttributeTargets.ReturnValue) != 0)
 684                                 sb.Append ("return, ");
 685
 686 #if NET_2_0
 687                         if ((targets & AttributeTargets.GenericParameter) != 0)
 688                                 sb.Append ("type parameter, ");
 689 #endif
 690                         return sb.Remove (sb.Length - 2, 2).ToString ();
 691                 }
 692
 693                 /// <summary>
 694                 /// Returns AttributeUsage attribute for this type
 695                 /// </summary>
 696                 AttributeUsageAttribute GetAttributeUsage ()
 697                 {
 698                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 699                         if (ua != null)
 700                                 return ua;
 701
 702                         Class attr_class = TypeManager.LookupClass (Type);
 703
 704                         if (attr_class == null) {
 705                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 706                                 ua = (AttributeUsageAttribute)usage_attr [0];
 707                                 usage_attr_cache.Add (Type, ua);
 708                                 return ua;
 709                         }
 710
 711                         Attribute a = attr_class.OptAttributes == null
 712                                 ? null
 713                                 : attr_class.OptAttributes.Search (TypeManager.attribute_usage_type);
 714
 715                         ua = a == null
 716                                 ? DefaultUsageAttribute
 717                                 : a.GetAttributeUsageAttribute ();
 718
 719                         usage_attr_cache.Add (Type, ua);
 720                         return ua;
 721                 }
 722
 723                 AttributeUsageAttribute GetAttributeUsageAttribute ()
 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 DefaultUsageAttribute;
 732
 733                         AttributeUsageAttribute usage_attribute = new AttributeUsageAttribute ((AttributeTargets)pos_values [0]);
 734
 735                         object field = GetPropertyValue ("AllowMultiple");
 736                         if (field != null)
 737                                 usage_attribute.AllowMultiple = (bool)field;
 738
 739                         field = GetPropertyValue ("Inherited");
 740                         if (field != null)
 741                                 usage_attribute.Inherited = (bool)field;
 742
 743                         return usage_attribute;
 744                 }
 745
 746                 /// <summary>
 747                 /// Returns custom name of indexer
 748                 /// </summary>
 749                 public string GetIndexerAttributeValue ()
 750                 {
 751                         if (pos_values == null)
 752                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 753                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 754                                 Resolve ();
 755
 756                         if (resolve_error)
 757                                 return null;
 758
 759                         return pos_values [0] as string;
 760                 }
 761
 762                 /// <summary>
 763                 /// Returns condition of ConditionalAttribute
 764                 /// </summary>
 765                 public string GetConditionalAttributeValue ()
 766                 {
 767                         if (pos_values == null)
 768                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 769                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 770                                 Resolve ();
 771
 772                         if (resolve_error)
 773                                 return null;
 774
 775                         return (string)pos_values [0];
 776                 }
 777
 778                 /// <summary>
 779                 /// Creates the instance of ObsoleteAttribute from this attribute instance
 780                 /// </summary>
 781                 public ObsoleteAttribute GetObsoleteAttribute ()
 782                 {
 783                         if (pos_values == null)
 784                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 785                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 786                                 Resolve ();
 787
 788                         if (resolve_error)
 789                                 return null;
 790
 791                         if (pos_values == null || pos_values.Length == 0)
 792                                 return new ObsoleteAttribute ();
 793
 794                         if (pos_values.Length == 1)
 795                                 return new ObsoleteAttribute ((string)pos_values [0]);
 796
 797                         return new ObsoleteAttribute ((string)pos_values [0], (bool)pos_values [1]);
 798                 }
 799
 800                 /// <summary>
 801                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 802                 /// before ApplyAttribute. We need to resolve the arguments.
 803                 /// This situation occurs when class deps is differs from Emit order.
 804                 /// </summary>
 805                 public bool GetClsCompliantAttributeValue ()
 806                 {
 807                         if (pos_values == null)
 808                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 809                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 810                                 Resolve ();
 811
 812                         if (resolve_error)
 813                                 return false;
 814
 815                         return (bool)pos_values [0];
 816                 }
 817
 818                 public Type GetCoClassAttributeValue ()
 819                 {
 820                         if (pos_values == null)
 821                                 Resolve ();
 822
 823                         if (resolve_error)
 824                                 return null;
 825
 826                         return (Type)pos_values [0];
 827                 }
 828
 829                 public bool CheckTarget ()
 830                 {
 831                         string[] valid_targets = owner.ValidAttributeTargets;
 832                         if (ExplicitTarget == null || ExplicitTarget == valid_targets [0]) {
 833                                 Target = owner.AttributeTargets;
 834                                 return true;
 835                         }
 836
 837                         // TODO: we can skip the first item
 838                         if (((IList) valid_targets).Contains (ExplicitTarget)) {
 839                                 switch (ExplicitTarget) {
 840                                         case "return": Target = AttributeTargets.ReturnValue; return true;
 841                                         case "param": Target = AttributeTargets.Parameter; return true;
 842                                         case "field": Target = AttributeTargets.Field; return true;
 843                                         case "method": Target = AttributeTargets.Method; return true;
 844                                         case "property": Target = AttributeTargets.Property; return true;
 845                                 }
 846                                 throw new InternalErrorException ("Unknown explicit target: " + ExplicitTarget);
 847                         }
 848
 849                         StringBuilder sb = new StringBuilder ();
 850                         foreach (string s in valid_targets) {
 851                                 sb.Append (s);
 852                                 sb.Append (", ");
 853                         }
 854                         sb.Remove (sb.Length - 2, 2);
 855                         Report.Error (657, Location, "`{0}' is not a valid attribute location for this declaration. " +
 856                                 "Valid attribute locations for this declaration are `{1}'", ExplicitTarget, sb.ToString ());
 857                         return false;
 858                 }
 859
 860                 /// <summary>
 861                 /// Tests permitted SecurityAction for assembly or other types
 862                 /// </summary>
 863                 public bool CheckSecurityActionValidity (bool for_assembly)
 864                 {
 865                         SecurityAction action  = GetSecurityActionValue ();
 866
 867                         if ((action == SecurityAction.RequestMinimum || action == SecurityAction.RequestOptional ||
 868                              action == SecurityAction.RequestRefuse) && for_assembly)
 869                                 return true;
 870
 871                         if (!for_assembly) {
 872                                 if (action < SecurityAction.Demand || action > SecurityAction.InheritanceDemand) {
 873                                         Error_AttributeEmitError ("SecurityAction is out of range");
 874                                         return false;
 875                                 }
 876
 877                                 if ((action != SecurityAction.RequestMinimum && action != SecurityAction.RequestOptional &&
 878                                      action != SecurityAction.RequestRefuse) && !for_assembly)
 879                                         return true;
 880                         }
 881
 882                         Error_AttributeEmitError (String.Concat ("SecurityAction `", action, "' is not valid for this declaration"));
 883                         return false;
 884                 }
 885
 886                 System.Security.Permissions.SecurityAction GetSecurityActionValue ()
 887                 {
 888                         return (SecurityAction)pos_values [0];
 889                 }
 890
 891                 /// <summary>
 892                 /// Creates instance of SecurityAttribute class and add result of CreatePermission method to permission table.
 893                 /// </summary>
 894                 /// <returns></returns>
 895                 public void ExtractSecurityPermissionSet (ListDictionary permissions)
 896                 {
 897                         Type orig_assembly_type = null;
 898
 899                         if (TypeManager.LookupDeclSpace (Type) != null) {
 900                                 if (!RootContext.StdLib) {
 901                                         orig_assembly_type = Type.GetType (Type.FullName);
 902                                 } else {
 903                                         string orig_version_path = Environment.GetEnvironmentVariable ("__SECURITY_BOOTSTRAP_DB");
 904                                         if (orig_version_path == null) {
 905                                                 Error_AttributeEmitError ("security custom attributes can not be referenced from defining assembly");
 906                                                 return;
 907                                         }
 908
 909                                         if (orig_sec_assembly == null) {
 910                                                 string file = Path.Combine (orig_version_path, Driver.OutputFile);
 911                                                 orig_sec_assembly = Assembly.LoadFile (file);
 912                                         }
 913
 914                                         orig_assembly_type = orig_sec_assembly.GetType (Type.FullName, true);
 915                                         if (orig_assembly_type == null) {
 916                                                 Report.Warning (-112, 1, Location, "Self-referenced security attribute `{0}' " +
 917                                                                 "was not found in previous version of assembly");
 918                                                 return;
 919                                         }
 920                                 }
 921                         }
 922
 923                         SecurityAttribute sa;
 924                         // For all non-selfreferencing security attributes we can avoid all hacks
 925                         if (orig_assembly_type == null) {
 926                                 sa = (SecurityAttribute) Activator.CreateInstance (Type, pos_values);
 927
 928                                 if (prop_info_arr != null) {
 929                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 930                                                 PropertyInfo pi = prop_info_arr [i];
 931                                                 pi.SetValue (sa, prop_values_arr [i], null);
 932                                         }
 933                                 }
 934                         } else {
 935                                 // HACK: All security attributes have same ctor syntax
 936                                 sa = (SecurityAttribute) Activator.CreateInstance (orig_assembly_type, new object[] { GetSecurityActionValue () } );
 937
 938                                 // All types are from newly created assembly but for invocation with old one we need to convert them
 939                                 if (prop_info_arr != null) {
 940                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 941                                                 PropertyInfo emited_pi = prop_info_arr [i];
 942                                                 PropertyInfo pi = orig_assembly_type.GetProperty (emited_pi.Name, emited_pi.PropertyType);
 943
 944                                                 object old_instance = pi.PropertyType.IsEnum ?
 945                                                         System.Enum.ToObject (pi.PropertyType, prop_values_arr [i]) :
 946                                                         prop_values_arr [i];
 947
 948                                                 pi.SetValue (sa, old_instance, null);
 949                                         }
 950                                 }
 951                         }
 952
 953                         IPermission perm;
 954                         perm = sa.CreatePermission ();
 955                         SecurityAction action = GetSecurityActionValue ();
 956
 957                         // IS is correct because for corlib we are using an instance from old corlib
 958                         if (!(perm is System.Security.CodeAccessPermission)) {
 959                                 switch (action) {
 960                                         case SecurityAction.Demand:
 961                                                 action = (SecurityAction)13;
 962                                                 break;
 963                                         case SecurityAction.LinkDemand:
 964                                                 action = (SecurityAction)14;
 965                                                 break;
 966                                         case SecurityAction.InheritanceDemand:
 967                                                 action = (SecurityAction)15;
 968                                                 break;
 969                                 }
 970                         }
 971
 972                         PermissionSet ps = (PermissionSet)permissions [action];
 973                         if (ps == null) {
 974                                 if (sa is PermissionSetAttribute)
 975                                         ps = new PermissionSet (sa.Unrestricted ? PermissionState.Unrestricted : PermissionState.None);
 976                                 else
 977                                         ps = new PermissionSet (PermissionState.None);
 978
 979                                 permissions.Add (action, ps);
 980                         } else if (!ps.IsUnrestricted () && (sa is PermissionSetAttribute) && sa.Unrestricted) {
 981                                 ps = ps.Union (new PermissionSet (PermissionState.Unrestricted));
 982                                 permissions [action] = ps;
 983                         }
 984                         ps.AddPermission (perm);
 985                 }
 986
 987                 object GetValue (object value)
 988                 {
 989                         if (value is EnumConstant)
 990                                 return ((EnumConstant) value).GetValue ();
 991                         else
 992                                 return value;
 993                 }
 994
 995                 public object GetPropertyValue (string name)
 996                 {
 997                         if (prop_info_arr == null)
 998                                 return null;
 999
1000                         for (int i = 0; i < prop_info_arr.Length; ++i) {
1001                                 if (prop_info_arr [i].Name == name)
1002                                         return prop_values_arr [i];
1003                         }
1004
1005                         return null;
1006                 }
1007
1008                 object GetFieldValue (string name)
1009                 {
1010                         int i;
1011                         if (field_info_arr == null)
1012                                 return null;
1013                         i = 0;
1014                         foreach (FieldInfo fi in field_info_arr) {
1015                                 if (fi.Name == name)
1016                                         return GetValue (field_values_arr [i]);
1017                                 i++;
1018                         }
1019                         return null;
1020                 }
1021
1022                 //
1023                 // Theoretically, we can get rid of this, since FieldBuilder.SetCustomAttribute()
1024                 // and ParameterBuilder.SetCustomAttribute() are supposed to handle this attribute.
1025                 // However, we can't, since it appears that the .NET 1.1 SRE hangs when given a MarshalAsAttribute.
1026                 //
1027                 public UnmanagedMarshal GetMarshal (Attributable attr)
1028                 {
1029                         UnmanagedType UnmanagedType;
1030                         if (!RootContext.StdLib || pos_values [0].GetType () != typeof (UnmanagedType))
1031                                 UnmanagedType = (UnmanagedType) System.Enum.ToObject (typeof (UnmanagedType), pos_values [0]);
1032                         else
1033                                 UnmanagedType = (UnmanagedType) pos_values [0];
1034
1035                         object value = GetFieldValue ("SizeParamIndex");
1036                         if (value != null && UnmanagedType != UnmanagedType.LPArray) {
1037                                 Error_AttributeEmitError ("SizeParamIndex field is not valid for the specified unmanaged type");
1038                                 return null;
1039                         }
1040
1041                         object o = GetFieldValue ("ArraySubType");
1042                         UnmanagedType array_sub_type = o == null ? (UnmanagedType) 0x50 /* NATIVE_MAX */ : (UnmanagedType) o;
1043
1044                         switch (UnmanagedType) {
1045                         case UnmanagedType.CustomMarshaler: {
1046                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
1047                                         BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
1048                                 if (define_custom == null) {
1049                                         Report.RuntimeMissingSupport (Location, "set marshal info");
1050                                         return null;
1051                                 }
1052
1053                                 object [] args = new object [4];
1054                                 args [0] = GetFieldValue ("MarshalTypeRef");
1055                                 args [1] = GetFieldValue ("MarshalCookie");
1056                                 args [2] = GetFieldValue ("MarshalType");
1057                                 args [3] = Guid.Empty;
1058                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
1059                         }
1060                         case UnmanagedType.LPArray: {
1061                                 object size_const = GetFieldValue ("SizeConst");
1062                                 object size_param_index = GetFieldValue ("SizeParamIndex");
1063
1064                                 if ((size_const != null) || (size_param_index != null)) {
1065                                         MethodInfo define_array = typeof (UnmanagedMarshal).GetMethod ("DefineLPArrayInternal",
1066                                                 BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
1067                                         if (define_array == null) {
1068                                                 Report.RuntimeMissingSupport (Location, "set marshal info");
1069                                                 return null;
1070                                         }
1071
1072                                         object [] args = new object [3];
1073                                         args [0] = array_sub_type;
1074                                         args [1] = size_const == null ? -1 : size_const;
1075                                         args [2] = size_param_index == null ? -1 : size_param_index;
1076                                         return (UnmanagedMarshal) define_array.Invoke (null, args);
1077                                 }
1078                                 else
1079                                         return UnmanagedMarshal.DefineLPArray (array_sub_type);
1080                         }
1081                         case UnmanagedType.SafeArray:
1082                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
1083
1084                         case UnmanagedType.ByValArray:
1085                                 FieldMember fm = attr as FieldMember;
1086                                 if (fm == null) {
1087                                         Error_AttributeEmitError ("Specified unmanaged type is only valid on fields");
1088                                         return null;
1089                                 }
1090                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
1091
1092                         case UnmanagedType.ByValTStr:
1093                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
1094
1095                         default:
1096                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
1097                         }
1098                 }
1099
1100                 public CharSet GetCharSetValue ()
1101                 {
1102                         return (CharSet)System.Enum.Parse (typeof (CharSet), pos_values [0].ToString ());
1103                 }
1104
1105                 public MethodImplOptions GetMethodImplOptions ()
1106                 {
1107                         if (pos_values [0].GetType () != typeof (MethodImplOptions))
1108                                 return (MethodImplOptions)System.Enum.ToObject (typeof (MethodImplOptions), pos_values [0]);
1109                         return (MethodImplOptions)pos_values [0];
1110                 }
1111
1112                 public LayoutKind GetLayoutKindValue ()
1113                 {
1114                         if (!RootContext.StdLib || pos_values [0].GetType () != typeof (LayoutKind))
1115                                 return (LayoutKind)System.Enum.ToObject (typeof (LayoutKind), pos_values [0]);
1116
1117                         return (LayoutKind)pos_values [0];
1118                 }
1119
1120                 public override bool Equals (object obj)
1121                 {
1122                         Attribute a = obj as Attribute;
1123                         if (a == null)
1124                                 return false;
1125
1126                         return Type == a.Type && Target == a.Target;
1127                 }
1128
1129                 public override int GetHashCode ()
1130                 {
1131                         return base.GetHashCode ();
1132                 }
1133
1134                 /// <summary>
1135                 /// Emit attribute for Attributable symbol
1136                 /// </summary>
1137                 public void Emit (ListDictionary allEmitted)
1138                 {
1139                         CustomAttributeBuilder cb = Resolve ();
1140                         if (cb == null)
1141                                 return;
1142
1143                         AttributeUsageAttribute usage_attr = GetAttributeUsage ();
1144                         if ((usage_attr.ValidOn & Target) == 0) {
1145                                 Report.Error (592, Location, "The attribute `{0}' is not valid on this declaration type. " +
1146                                               "It is valid on `{1}' declarations only",
1147                                         GetSignatureForError (), GetValidTargets ());
1148                                 return;
1149                         }
1150
1151                         try {
1152                                 owner.ApplyAttributeBuilder (this, cb);
1153                         }
1154                         catch (Exception e) {
1155                                 Error_AttributeEmitError (e.Message);
1156                                 return;
1157                         }
1158
1159                         if (!usage_attr.AllowMultiple && allEmitted != null) {
1160                                 if (allEmitted.Contains (this)) {
1161                                         ArrayList a = allEmitted [this] as ArrayList;
1162                                         if (a == null) {
1163                                                 a = new ArrayList (2);
1164                                                 allEmitted [this] = a;
1165                                         }
1166                                         a.Add (this);
1167                                 } else {
1168                                         allEmitted.Add (this, null);
1169                                 }
1170                         }
1171
1172                         if (!RootContext.VerifyClsCompliance)
1173                                 return;
1174
1175                         // Here we are testing attribute arguments for array usage (error 3016)
1176                         if (owner.IsClsComplianceRequired ()) {
1177                                 if (Arguments == null)
1178                                         return;
1179
1180                                 ArrayList pos_args = (ArrayList) Arguments [0];
1181                                 if (pos_args != null) {
1182                                         foreach (Argument arg in pos_args) {
1183                                                 // Type is undefined (was error 246)
1184                                                 if (arg.Type == null)
1185                                                         return;
1186
1187                                                 if (arg.Type.IsArray) {
1188                                                         Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1189                                                         return;
1190                                                 }
1191                                         }
1192                                 }
1193
1194                                 if (Arguments.Count < 2)
1195                                         return;
1196
1197                                 ArrayList named_args = (ArrayList) Arguments [1];
1198                                 foreach (DictionaryEntry de in named_args) {
1199                                         Argument arg  = (Argument) de.Value;
1200
1201                                         // Type is undefined (was error 246)
1202                                         if (arg.Type == null)
1203                                                 return;
1204
1205                                         if (arg.Type.IsArray) {
1206                                                 Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1207                                                 return;
1208                                         }
1209                                 }
1210                         }
1211                 }
1212
1213                 public MethodBuilder DefinePInvokeMethod (TypeBuilder builder, string name,
1214                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
1215                 {
1216                         if (pos_values == null)
1217                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
1218                                 // But because a lot of attribute class code must be rewritten will be better to wait...
1219                                 Resolve ();
1220
1221                         if (resolve_error)
1222                                 return null;
1223
1224                         string dll_name = (string)pos_values [0];
1225
1226                         // Default settings
1227                         CallingConvention cc = CallingConvention.Winapi;
1228                         CharSet charset = CodeGen.Module.DefaultCharSet;
1229                         bool preserve_sig = true;
1230                         string entry_point = name;
1231                         bool best_fit_mapping = false;
1232                         bool throw_on_unmappable = false;
1233                         bool exact_spelling = false;
1234                         bool set_last_error = false;
1235
1236                         bool best_fit_mapping_set = false;
1237                         bool throw_on_unmappable_set = false;
1238                         bool exact_spelling_set = false;
1239                         bool set_last_error_set = false;
1240
1241                         MethodInfo set_best_fit = null;
1242                         MethodInfo set_throw_on = null;
1243                         MethodInfo set_exact_spelling = null;
1244                         MethodInfo set_set_last_error = null;
1245
1246                         if (field_info_arr != null) {
1247
1248                                 for (int i = 0; i < field_info_arr.Length; i++) {
1249                                         switch (field_info_arr [i].Name) {
1250                                         case "BestFitMapping":
1251                                                 best_fit_mapping = (bool) field_values_arr [i];
1252                                                 best_fit_mapping_set = true;
1253                                                 break;
1254                                         case "CallingConvention":
1255                                                 cc = (CallingConvention) field_values_arr [i];
1256                                                 break;
1257                                         case "CharSet":
1258                                                 charset = (CharSet) field_values_arr [i];
1259                                                 break;
1260                                         case "EntryPoint":
1261                                                 entry_point = (string) field_values_arr [i];
1262                                                 break;
1263                                         case "ExactSpelling":
1264                                                 exact_spelling = (bool) field_values_arr [i];
1265                                                 exact_spelling_set = true;
1266                                                 break;
1267                                         case "PreserveSig":
1268                                                 preserve_sig = (bool) field_values_arr [i];
1269                                                 break;
1270                                         case "SetLastError":
1271                                                 set_last_error = (bool) field_values_arr [i];
1272                                                 set_last_error_set = true;
1273                                                 break;
1274                                         case "ThrowOnUnmappableChar":
1275                                                 throw_on_unmappable = (bool) field_values_arr [i];
1276                                                 throw_on_unmappable_set = true;
1277                                                 break;
1278                                         default:
1279                                                 throw new InternalErrorException (field_info_arr [i].ToString ());
1280                                         }
1281                                 }
1282                         }
1283
1284                         if (throw_on_unmappable_set || best_fit_mapping_set || exact_spelling_set || set_last_error_set) {
1285                                 set_best_fit = typeof (MethodBuilder).
1286                                         GetMethod ("set_BestFitMapping", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1287                                 set_throw_on = typeof (MethodBuilder).
1288                                         GetMethod ("set_ThrowOnUnmappableChar", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1289                                 set_exact_spelling = typeof (MethodBuilder).
1290                                         GetMethod ("set_ExactSpelling", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1291                                 set_set_last_error = typeof (MethodBuilder).
1292                                         GetMethod ("set_SetLastError", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1293
1294                                 if ((set_best_fit == null) || (set_throw_on == null) ||
1295                                     (set_exact_spelling == null) || (set_set_last_error == null)) {
1296                                         Report.Error (-1, Location,
1297                                                                   "The ThrowOnUnmappableChar, BestFitMapping, SetLastError, " +
1298                                                       "and ExactSpelling attributes can only be emitted when running on the mono runtime.");
1299                                         return null;
1300                                 }
1301                         }
1302
1303                         try {
1304                                 MethodBuilder mb = builder.DefinePInvokeMethod (
1305                                         name, dll_name, entry_point, flags | MethodAttributes.HideBySig | MethodAttributes.PinvokeImpl,
1306                                         CallingConventions.Standard, ret_type, param_types, cc, charset);
1307
1308                                 if (preserve_sig)
1309                                         mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1310
1311                                 if (throw_on_unmappable_set)
1312                                         set_throw_on.Invoke (mb, 0, null, new object [] { throw_on_unmappable }, null);
1313                                 if (best_fit_mapping_set)
1314                                         set_best_fit.Invoke (mb, 0, null, new object [] { best_fit_mapping }, null);
1315                                 if (exact_spelling_set)
1316                                         set_exact_spelling.Invoke  (mb, 0, null, new object [] { exact_spelling }, null);
1317                                 if (set_last_error_set)
1318                                         set_set_last_error.Invoke  (mb, 0, null, new object [] { set_last_error }, null);
1319
1320                                 return mb;
1321                         }
1322                         catch (ArgumentException e) {
1323                                 Error_AttributeEmitError (e.Message);
1324                                 return null;
1325                         }
1326                 }
1327
1328                 private Expression GetValue ()
1329                 {
1330                         if ((Arguments == null) || (Arguments.Count < 1))
1331                                 return null;
1332                         ArrayList al = (ArrayList) Arguments [0];
1333                         if ((al == null) || (al.Count < 1))
1334                                 return null;
1335                         Argument arg = (Argument) al [0];
1336                         if ((arg == null) || (arg.Expr == null))
1337                                 return null;
1338                         return arg.Expr;
1339                 }
1340
1341                 public string GetString ()
1342                 {
1343                         Expression e = GetValue ();
1344                         if (e is StringLiteral)
1345                                 return (e as StringLiteral).Value;
1346                         return null;
1347                 }
1348
1349                 public bool GetBoolean ()
1350                 {
1351                         Expression e = GetValue ();
1352                         if (e is BoolLiteral)
1353                                 return (e as BoolLiteral).Value;
1354                         return false;
1355                 }
1356         }
1357
1358
1359         /// <summary>
1360         /// For global attributes (assembly, module) we need special handling.
1361         /// Attributes can be located in the several files
1362         /// </summary>
1363         public class GlobalAttribute : Attribute
1364         {
1365                 public readonly NamespaceEntry ns;
1366
1367                 public GlobalAttribute (NamespaceEntry ns, string target,
1368                                         Expression left_expr, string identifier, ArrayList args, Location loc, bool nameEscaped):
1369                         base (target, left_expr, identifier, args, loc, nameEscaped)
1370                 {
1371                         this.ns = ns;
1372                 }
1373
1374                 void Enter ()
1375                 {
1376                         // RootContext.Tree.Types has a single NamespaceEntry which gets overwritten
1377                         // each time a new file is parsed.  However, we need to use the NamespaceEntry
1378                         // in effect where the attribute was used.  Since code elsewhere cannot assume
1379                         // that the NamespaceEntry is right, just overwrite it.
1380                         //
1381                         // Precondition: RootContext.Tree.Types == null
1382
1383                         if (RootContext.Tree.Types.NamespaceEntry != null)
1384                                 throw new InternalErrorException (Location + " non-null NamespaceEntry");
1385
1386                         RootContext.Tree.Types.NamespaceEntry = ns;
1387                 }
1388
1389                 void Leave ()
1390                 {
1391                         RootContext.Tree.Types.NamespaceEntry = null;
1392                 }
1393
1394                 protected override FullNamedExpression ResolveAsTypeStep (Expression expr, IResolveContext ec, bool silent)
1395                 {
1396                         try {
1397                                 Enter ();
1398                                 return base.ResolveAsTypeStep (expr, ec, silent);
1399                         }
1400                         finally {
1401                                 Leave ();
1402                         }
1403                 }
1404
1405
1406                 protected override FullNamedExpression ResolveAsTypeTerminal (Expression expr, IResolveContext ec, bool silent)
1407                 {
1408                         try {
1409                                 Enter ();
1410                                 return base.ResolveAsTypeTerminal (expr, ec, silent);
1411                         }
1412                         finally {
1413                                 Leave ();
1414                         }
1415                 }
1416
1417                 protected override ConstructorInfo ResolveArguments ()
1418                 {
1419                         try {
1420                                 Enter ();
1421                                 return base.ResolveArguments ();
1422                         }
1423                         finally {
1424                                 Leave ();
1425                         }
1426                 }
1427         }
1428
1429         public class Attributes {
1430                 public readonly ArrayList Attrs;
1431
1432                 public Attributes (Attribute a)
1433                 {
1434                         Attrs = new ArrayList ();
1435                         Attrs.Add (a);
1436                 }
1437
1438                 public Attributes (ArrayList attrs)
1439                 {
1440                         Attrs = attrs;
1441                 }
1442
1443                 public void AddAttributes (ArrayList attrs)
1444                 {
1445                         Attrs.AddRange (attrs);
1446                 }
1447
1448                 public void AttachTo (Attributable attributable)
1449                 {
1450                         foreach (Attribute a in Attrs)
1451                                 a.AttachTo (attributable);
1452                 }
1453
1454                 /// <summary>
1455                 /// Checks whether attribute target is valid for the current element
1456                 /// </summary>
1457                 public bool CheckTargets ()
1458                 {
1459                         foreach (Attribute a in Attrs) {
1460                                 if (!a.CheckTarget ())
1461                                         return false;
1462                         }
1463                         return true;
1464                 }
1465
1466                 public Attribute Search (Type t)
1467                 {
1468                         foreach (Attribute a in Attrs) {
1469                                 if (a.ResolveType () == t)
1470                                         return a;
1471                         }
1472                         return null;
1473                 }
1474
1475                 /// <summary>
1476                 /// Returns all attributes of type 't'. Use it when attribute is AllowMultiple = true
1477                 /// </summary>
1478                 public Attribute[] SearchMulti (Type t)
1479                 {
1480                         ArrayList ar = null;
1481
1482                         foreach (Attribute a in Attrs) {
1483                                 if (a.ResolveType () == t) {
1484                                         if (ar == null)
1485                                                 ar = new ArrayList ();
1486                                         ar.Add (a);
1487                                 }
1488                         }
1489
1490                         return ar == null ? null : ar.ToArray (typeof (Attribute)) as Attribute[];
1491                 }
1492
1493                 public void Emit ()
1494                 {
1495                         CheckTargets ();
1496
1497                         ListDictionary ld = Attrs.Count > 1 ? new ListDictionary () : null;
1498
1499                         foreach (Attribute a in Attrs)
1500                                 a.Emit (ld);
1501
1502                         if (ld == null || ld.Count == 0)
1503                                 return;
1504
1505                         foreach (DictionaryEntry d in ld) {
1506                                 if (d.Value == null)
1507                                         continue;
1508
1509                                 foreach (Attribute collision in (ArrayList)d.Value)
1510                                         Report.SymbolRelatedToPreviousError (collision.Location, "");
1511
1512                                 Attribute a = (Attribute)d.Key;
1513                                 Report.Error (579, a.Location, "The attribute `{0}' cannot be applied multiple times", a.GetSignatureForError ());
1514                         }
1515                 }
1516
1517                 public bool Contains (Type t)
1518                 {
1519                         return Search (t) != null;
1520                 }
1521         }
1522
1523         /// <summary>
1524         /// Helper class for attribute verification routine.
1525         /// </summary>
1526         sealed class AttributeTester
1527         {
1528                 static PtrHashtable analyzed_types = new PtrHashtable ();
1529                 static PtrHashtable analyzed_types_obsolete = new PtrHashtable ();
1530                 static PtrHashtable analyzed_member_obsolete = new PtrHashtable ();
1531                 static PtrHashtable analyzed_method_excluded = new PtrHashtable ();
1532
1533 #if NET_2_0
1534                 static PtrHashtable fixed_buffer_cache = new PtrHashtable ();
1535 #endif
1536
1537                 static object TRUE = new object ();
1538                 static object FALSE = new object ();
1539
1540                 private AttributeTester ()
1541                 {
1542                 }
1543
1544                 public enum Result {
1545                         Ok,
1546                         RefOutArrayError,
1547                         ArrayArrayError
1548                 }
1549
1550                 /// <summary>
1551                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1552                 /// It tests differing only in ref or out, or in array rank.
1553                 /// </summary>
1554                 public static Result AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1555                 {
1556                         if (types_a == null || types_b == null)
1557                                 return Result.Ok;
1558
1559                         if (types_a.Length != types_b.Length)
1560                                 return Result.Ok;
1561
1562                         Result result = Result.Ok;
1563                         for (int i = 0; i < types_b.Length; ++i) {
1564                                 Type aType = types_a [i];
1565                                 Type bType = types_b [i];
1566
1567                                 if (aType.IsArray && bType.IsArray) {
1568                                         Type a_el_type = aType.GetElementType ();
1569                                         Type b_el_type = bType.GetElementType ();
1570                                         if (aType.GetArrayRank () != bType.GetArrayRank () && a_el_type == b_el_type) {
1571                                                 result = Result.RefOutArrayError;
1572                                                 continue;
1573                                         }
1574
1575                                         if (a_el_type.IsArray || b_el_type.IsArray) {
1576                                                 result = Result.ArrayArrayError;
1577                                                 continue;
1578                                         }
1579                                 }
1580
1581                                 Type aBaseType = aType;
1582                                 bool is_either_ref_or_out = false;
1583
1584                                 if (aType.IsByRef || aType.IsPointer) {
1585                                         aBaseType = aType.GetElementType ();
1586                                         is_either_ref_or_out = true;
1587                                 }
1588
1589                                 Type bBaseType = bType;
1590                                 if (bType.IsByRef || bType.IsPointer)
1591                                 {
1592                                         bBaseType = bType.GetElementType ();
1593                                         is_either_ref_or_out = !is_either_ref_or_out;
1594                                 }
1595
1596                                 if (aBaseType != bBaseType)
1597                                         return Result.Ok;
1598
1599                                 if (is_either_ref_or_out)
1600                                         result = Result.RefOutArrayError;
1601                         }
1602                         return result;
1603                 }
1604
1605                 /// <summary>
1606                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1607                 /// </summary>
1608                 public static bool IsClsCompliant (Type type)
1609                 {
1610                         if (type == null)
1611                                 return true;
1612
1613                         object type_compliance = analyzed_types[type];
1614                         if (type_compliance != null)
1615                                 return type_compliance == TRUE;
1616
1617                         if (type.IsPointer) {
1618                                 analyzed_types.Add (type, null);
1619                                 return false;
1620                         }
1621
1622                         bool result;
1623                         if (type.IsArray || type.IsByRef)       {
1624                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1625                         } else {
1626                                 result = AnalyzeTypeCompliance (type);
1627                         }
1628                         analyzed_types.Add (type, result ? TRUE : FALSE);
1629                         return result;
1630                 }
1631
1632                 /// <summary>
1633                 /// Returns IFixedBuffer implementation if field is fixed buffer else null.
1634                 /// </summary>
1635                 public static IFixedBuffer GetFixedBuffer (FieldInfo fi)
1636                 {
1637                         FieldBase fb = TypeManager.GetField (fi);
1638                         if (fb != null) {
1639                                 return fb as IFixedBuffer;
1640                         }
1641
1642 #if NET_2_0
1643                         object o = fixed_buffer_cache [fi];
1644                         if (o == null) {
1645                                 if (System.Attribute.GetCustomAttribute (fi, TypeManager.fixed_buffer_attr_type) == null) {
1646                                         fixed_buffer_cache.Add (fi, FALSE);
1647                                         return null;
1648                                 }
1649
1650                                 IFixedBuffer iff = new FixedFieldExternal (fi);
1651                                 fixed_buffer_cache.Add (fi, iff);
1652                                 return iff;
1653                         }
1654
1655                         if (o == FALSE)
1656                                 return null;
1657
1658                         return (IFixedBuffer)o;
1659 #else
1660                         return null;
1661 #endif
1662                 }
1663
1664                 public static void VerifyModulesClsCompliance ()
1665                 {
1666                         Module[] modules = RootNamespace.Global.Modules;
1667                         if (modules == null)
1668                                 return;
1669
1670                         // The first module is generated assembly
1671                         for (int i = 1; i < modules.Length; ++i) {
1672                                 Module module = modules [i];
1673                                 if (!IsClsCompliant (module)) {
1674                                         Report.Error (3013, "Added modules must be marked with the CLSCompliant attribute " +
1675                                                       "to match the assembly", module.Name);
1676                                         return;
1677                                 }
1678                         }
1679                 }
1680
1681                 public static Type GetImportedIgnoreCaseClsType (string name)
1682                 {
1683                         foreach (Assembly a in RootNamespace.Global.Assemblies) {
1684                                 Type t = a.GetType (name, false, true);
1685                                 if (t == null)
1686                                         continue;
1687
1688                                 if (IsClsCompliant (t))
1689                                         return t;
1690                         }
1691                         return null;
1692                 }
1693
1694                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1695                 {
1696                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1697                         if (CompliantAttribute.Length == 0)
1698                                 return false;
1699
1700                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1701                 }
1702
1703                 static bool AnalyzeTypeCompliance (Type type)
1704                 {
1705                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1706                         if (ds != null) {
1707                                 return ds.IsClsComplianceRequired ();
1708                         }
1709
1710                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1711                         if (CompliantAttribute.Length == 0)
1712                                 return IsClsCompliant (type.Assembly);
1713
1714                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1715                 }
1716
1717                 /// <summary>
1718                 /// Returns instance of ObsoleteAttribute when type is obsolete
1719                 /// </summary>
1720                 public static ObsoleteAttribute GetObsoleteAttribute (Type type)
1721                 {
1722                         object type_obsolete = analyzed_types_obsolete [type];
1723                         if (type_obsolete == FALSE)
1724                                 return null;
1725
1726                         if (type_obsolete != null)
1727                                 return (ObsoleteAttribute)type_obsolete;
1728
1729                         ObsoleteAttribute result = null;
1730                         if (type.IsByRef || type.IsArray || type.IsPointer) {
1731                                 result = GetObsoleteAttribute (TypeManager.GetElementType (type));
1732                         } else {
1733                                 DeclSpace type_ds = TypeManager.LookupDeclSpace (type);
1734
1735                                 // Type is external, we can get attribute directly
1736                                 if (type_ds == null) {
1737                                         object[] attribute = type.GetCustomAttributes (TypeManager.obsolete_attribute_type, false);
1738                                         if (attribute.Length == 1)
1739                                                 result = (ObsoleteAttribute)attribute [0];
1740                                 } else {
1741                                         // Is null during corlib bootstrap
1742                                         if (TypeManager.obsolete_attribute_type != null)
1743                                                 result = type_ds.GetObsoleteAttribute ();
1744                                 }
1745                         }
1746
1747                         // Cannot use .Add because of corlib bootstrap
1748                         analyzed_types_obsolete [type] = result == null ? FALSE : result;
1749                         return result;
1750                 }
1751
1752                 /// <summary>
1753                 /// Returns instance of ObsoleteAttribute when method is obsolete
1754                 /// </summary>
1755                 public static ObsoleteAttribute GetMethodObsoleteAttribute (MethodBase mb)
1756                 {
1757                         IMethodData mc = TypeManager.GetMethod (mb);
1758                         if (mc != null)
1759                                 return mc.GetObsoleteAttribute ();
1760
1761                         // compiler generated methods are not registered by AddMethod
1762                         if (mb.DeclaringType is TypeBuilder)
1763                                 return null;
1764
1765                         if (mb.IsSpecialName) {
1766                                 PropertyInfo pi = PropertyExpr.AccessorTable [mb] as PropertyInfo;
1767                                 if (pi != null) {
1768                                         // FIXME: This is buggy as properties from this assembly are included as well
1769                                         return null;
1770                                         //return GetMemberObsoleteAttribute (pi);
1771                                 }
1772                         }
1773
1774                         return GetMemberObsoleteAttribute (mb);
1775                 }
1776
1777                 /// <summary>
1778                 /// Returns instance of ObsoleteAttribute when member is obsolete
1779                 /// </summary>
1780                 public static ObsoleteAttribute GetMemberObsoleteAttribute (MemberInfo mi)
1781                 {
1782                         object type_obsolete = analyzed_member_obsolete [mi];
1783                         if (type_obsolete == FALSE)
1784                                 return null;
1785
1786                         if (type_obsolete != null)
1787                                 return (ObsoleteAttribute)type_obsolete;
1788
1789                         ObsoleteAttribute oa = System.Attribute.GetCustomAttribute (mi, TypeManager.obsolete_attribute_type, false)
1790                                 as ObsoleteAttribute;
1791                         analyzed_member_obsolete.Add (mi, oa == null ? FALSE : oa);
1792                         return oa;
1793                 }
1794
1795                 /// <summary>
1796                 /// Common method for Obsolete error/warning reporting.
1797                 /// </summary>
1798                 public static void Report_ObsoleteMessage (ObsoleteAttribute oa, string member, Location loc)
1799                 {
1800                         if (oa.IsError) {
1801                                 Report.Error (619, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1802                                 return;
1803                         }
1804
1805                         if (oa.Message == null) {
1806                                 Report.Warning (612, 1, loc, "`{0}' is obsolete", member);
1807                                 return;
1808                         }
1809                         Report.Warning (618, 2, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1810                 }
1811
1812                 public static bool IsConditionalMethodExcluded (MethodBase mb)
1813                 {
1814                         object excluded = analyzed_method_excluded [mb];
1815                         if (excluded != null)
1816                                 return excluded == TRUE ? true : false;
1817
1818                         ConditionalAttribute[] attrs = mb.GetCustomAttributes (TypeManager.conditional_attribute_type, true)
1819                                 as ConditionalAttribute[];
1820                         if (attrs.Length == 0) {
1821                                 analyzed_method_excluded.Add (mb, FALSE);
1822                                 return false;
1823                         }
1824
1825                         foreach (ConditionalAttribute a in attrs) {
1826                                 if (RootContext.AllDefines.Contains (a.ConditionString)) {
1827                                         analyzed_method_excluded.Add (mb, FALSE);
1828                                         return false;
1829                                 }
1830                         }
1831                         analyzed_method_excluded.Add (mb, TRUE);
1832                         return true;
1833                 }
1834
1835                 /// <summary>
1836                 /// Analyzes class whether it has attribute which has ConditionalAttribute
1837                 /// and its condition is not defined.
1838                 /// </summary>
1839                 public static bool IsAttributeExcluded (Type type)
1840                 {
1841                         if (!type.IsClass)
1842                                 return false;
1843
1844                         Class class_decl = TypeManager.LookupDeclSpace (type) as Class;
1845
1846                         // TODO: add caching
1847                         // TODO: merge all Type bases attribute caching to one cache to save memory
1848                         if (class_decl == null) {
1849                                 object[] attributes = type.GetCustomAttributes (TypeManager.conditional_attribute_type, false);
1850                                 foreach (ConditionalAttribute ca in attributes) {
1851                                         if (RootContext.AllDefines.Contains (ca.ConditionString))
1852                                                 return false;
1853                                 }
1854                                 return attributes.Length > 0;
1855                         }
1856
1857                         return class_decl.IsExcluded ();
1858                 }
1859
1860                 public static Type GetCoClassAttribute (Type type)
1861                 {
1862                         TypeContainer tc = TypeManager.LookupInterface (type);
1863                         if (tc == null) {
1864                                 object[] o = type.GetCustomAttributes (TypeManager.coclass_attr_type, false);
1865                                 if (o.Length < 1)
1866                                         return null;
1867                                 return ((System.Runtime.InteropServices.CoClassAttribute)o[0]).CoClass;
1868                         }
1869
1870                         if (tc.OptAttributes == null)
1871                                 return null;
1872
1873                         Attribute a = tc.OptAttributes.Search (TypeManager.coclass_attr_type);
1874                         if (a == null)
1875                                 return null;
1876
1877                         return a.GetCoClassAttributeValue ();
1878                 }
1879         }
1880 }