mcs/mbas/attribute.cs

   1 //
   2 // attribute.cs: Attribute Handler
   3 //
   4 // Author: Ravi Pratap (ravi@ximian.com)
   5 //
   6 // Licensed under the terms of the GNU GPL
   7 //
   8 // (C) 2001 Ximian, Inc (http://www.ximian.com)
   9 //
  10 //
  11
  12 using System;
  13 using System.Diagnostics;
  14 using System.Collections;
  15 using System.Reflection;
  16 using System.Reflection.Emit;
  17 using System.Runtime.InteropServices;
  18 using System.Runtime.CompilerServices;
  19 using System.Text;
  20
  21 namespace Mono.MonoBASIC {
  22
  23         public class Attribute {
  24                 public readonly string    Name;
  25                 public readonly ArrayList Arguments;
  26
  27                 Location Location;
  28
  29                 public Type Type;
  30
  31                 //
  32                 // The following are only meaningful when the attribute
  33                 // being emitted is one of the builtin ones
  34                 //
  35                 AttributeTargets Targets;
  36                 bool AllowMultiple;
  37                 bool Inherited;
  38
  39                 bool UsageAttr = false;
  40
  41                 MethodImplOptions ImplOptions;
  42                 UnmanagedType     UnmanagedType;
  43                 CustomAttributeBuilder cb;
  44
  45                 public Attribute (string name, ArrayList args, Location loc)
  46                 {
  47                         Name = name;
  48                         Arguments = args;
  49                         Location = loc;
  50                 }
  51
  52                 void Error_InvalidNamedArgument (string name)
  53                 {
  54                         Report.Error (617, Location, "'" + name + "' is not a valid named attribute " +
  55                                       "argument. Named attribute arguments must be fields which are not " +
  56                                       "readonly, static or const, or properties with a set accessor which "+
  57                                       "are not static.");
  58                 }
  59
  60                 void Error_AttributeArgumentNotValid ()
  61                 {
  62                         Report.Error (182, Location,
  63                                       "An attribute argument must be a constant expression, typeof " +
  64                                       "expression or array creation expression");
  65                 }
  66
  67                 static void Error_AttributeConstructorMismatch (Location loc)
  68                 {
  69                         Report.Error (
  70                                         -6, loc,
  71                                         "Could not find a constructor for this argument list.");
  72                 }
  73
  74                 private Type CheckAttributeType (EmitContext ec) {
  75                         Type t;
  76                         bool isattributeclass = true;
  77
  78                         t = RootContext.LookupType (ec.DeclSpace, Name, true, Location);
  79                         if (t != null) {
  80                                 isattributeclass = t.IsSubclassOf (TypeManager.attribute_type);
  81                                 if (isattributeclass)
  82                                         return t;
  83                         }
  84                         t = RootContext.LookupType (ec.DeclSpace, Name + "Attribute", true, Location);
  85                         if (t != null) {
  86                                 if (t.IsSubclassOf (TypeManager.attribute_type))
  87                                         return t;
  88                         }
  89                         if (!isattributeclass) {
  90                                 Report.Error (616, Location, "'" + Name + "': is not an attribute class");
  91                                 return null;
  92                         }
  93                         if (t != null) {
  94                                 Report.Error (616, Location, "'" + Name + "Attribute': is not an attribute class");
  95                                 return null;
  96                         }
  97                         Report.Error (
  98                                 246, Location, "Could not find attribute '" + Name + "' (are you" +
  99                                 " missing a using directive or an assembly reference ?)");
 100                         return null;
 101                 }
 102
 103                 public Type ResolveType (EmitContext ec)
 104                 {
 105                         Type = CheckAttributeType (ec);
 106                         return Type;
 107                 }
 108
 109
 110                 public CustomAttributeBuilder Resolve (EmitContext ec)
 111                 {
 112                         if (Type == null)
 113                                 Type = CheckAttributeType (ec);
 114                         if (Type == null)
 115                                 return null;
 116
 117                         bool MethodImplAttr = false;
 118                         bool MarshalAsAttr = false;
 119
 120                         UsageAttr = false;
 121
 122                         if (Type == TypeManager.attribute_usage_type)
 123                                 UsageAttr = true;
 124                         if (Type == TypeManager.methodimpl_attr_type)
 125                                 MethodImplAttr = true;
 126                         if (Type == TypeManager.marshal_as_attr_type)
 127                                 MarshalAsAttr = true;
 128
 129                         // Now we extract the positional and named arguments
 130
 131                         ArrayList pos_args = new ArrayList ();
 132                         ArrayList named_args = new ArrayList ();
 133                         int pos_arg_count = 0;
 134
 135                         if (Arguments != null) {
 136                                 pos_args = (ArrayList) Arguments [0];
 137                                 if (pos_args != null)
 138                                         pos_arg_count = pos_args.Count;
 139                                 if (Arguments.Count > 1)
 140                                         named_args = (ArrayList) Arguments [1];
 141                         }
 142
 143                         object [] pos_values = new object [pos_arg_count];
 144
 145                         //
 146                         // First process positional arguments
 147                         //
 148
 149                         int i;
 150                         for (i = 0; i < pos_arg_count; i++) {
 151                                 Argument a = (Argument) pos_args [i];
 152                                 Expression e;
 153
 154                                 if (!a.Resolve (ec, Location))
 155                                         return null;
 156
 157                                 e = a.Expr;
 158
 159                                 if (e is Constant) {
 160                                         pos_values [i] = ((Constant) e).GetValue ();
 161                                 } else if (e is TypeOf) {
 162                                         pos_values [i] = ((TypeOf) e).TypeArg;
 163                                 } else {
 164                                         Error_AttributeArgumentNotValid ();
 165                                         return null;
 166                                 }
 167
 168                                 if (UsageAttr)
 169                                         this.Targets = (AttributeTargets) pos_values [0];
 170
 171                                 if (MethodImplAttr)
 172                                         this.ImplOptions = (MethodImplOptions) pos_values [0];
 173
 174                                 if (MarshalAsAttr)
 175                                         this.UnmanagedType =
 176                                         (System.Runtime.InteropServices.UnmanagedType) pos_values [0];
 177                         }
 178
 179                         //
 180                         // Now process named arguments
 181                         //
 182
 183                         ArrayList field_infos = new ArrayList ();
 184                         ArrayList prop_infos  = new ArrayList ();
 185                         ArrayList field_values = new ArrayList ();
 186                         ArrayList prop_values = new ArrayList ();
 187
 188                         for (i = 0; i < named_args.Count; i++) {
 189                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 190                                 string member_name = (string) de.Key;
 191                                 Argument a  = (Argument) de.Value;
 192                                 Expression e;
 193
 194                                 if (!a.Resolve (ec, Location))
 195                                         return null;
 196
 197                                 Expression member = Expression.MemberLookup (
 198                                         ec, Type, member_name,
 199                                         MemberTypes.Field | MemberTypes.Property,
 200                                         BindingFlags.Public | BindingFlags.Instance,
 201                                         Location);
 202
 203                                 if (member == null || !(member is PropertyExpr || member is FieldExpr)) {
 204                                         Error_InvalidNamedArgument (member_name);
 205                                         return null;
 206                                 }
 207
 208                                 e = a.Expr;
 209                                 if (member is PropertyExpr) {
 210                                         PropertyExpr pe = (PropertyExpr) member;
 211                                         PropertyInfo pi = pe.PropertyInfo;
 212
 213                                         if (!pi.CanWrite) {
 214                                                 Error_InvalidNamedArgument (member_name);
 215                                                 return null;
 216                                         }
 217
 218                                         if (e is Constant) {
 219                                                 object o = ((Constant) e).GetValue ();
 220                                                 prop_values.Add (o);
 221
 222                                                 if (UsageAttr) {
 223                                                         if (member_name == "AllowMultiple")
 224                                                                 this.AllowMultiple = (bool) o;
 225                                                         if (member_name == "Inherited")
 226                                                                 this.Inherited = (bool) o;
 227                                                 }
 228
 229                                         } else if (e is TypeOf) {
 230                                                 prop_values.Add (((TypeOf) e).TypeArg);
 231                                         } else {
 232                                                 Error_AttributeArgumentNotValid ();
 233                                                 return null;
 234                                         }
 235
 236                                         prop_infos.Add (pi);
 237
 238                                 } else if (member is FieldExpr) {
 239                                         FieldExpr fe = (FieldExpr) member;
 240                                         FieldInfo fi = fe.FieldInfo;
 241
 242                                         if (fi.IsInitOnly) {
 243                                                 Error_InvalidNamedArgument (member_name);
 244                                                 return null;
 245                                         }
 246
 247                                         //
 248                                         // Handle charset here, and set the TypeAttributes
 249
 250                                         if (e is Constant){
 251                                                 object value = ((Constant) e).GetValue ();
 252
 253                                                 field_values.Add (value);
 254                                         } else if (e is TypeOf) {
 255                                                 field_values.Add (((TypeOf) e).TypeArg);
 256                                         } else {
 257                                                 Error_AttributeArgumentNotValid ();
 258                                                 return null;
 259                                         }
 260
 261                                         field_infos.Add (fi);
 262                                 }
 263                         }
 264
 265                         Expression mg = Expression.MemberLookup (
 266                                 ec, Type, ".ctor", MemberTypes.Constructor,
 267                                 BindingFlags.Public | BindingFlags.Instance, Location);
 268
 269                         if (mg == null) {
 270                                 Error_AttributeConstructorMismatch (Location);
 271                                 return null;
 272                         }
 273
 274                         MethodBase constructor = Invocation.OverloadResolve (
 275                                 ec, (MethodGroupExpr) mg, pos_args, Location);
 276
 277                         if (constructor == null) {
 278                                 Error_AttributeConstructorMismatch (Location);
 279                                 return null;
 280                         }
 281
 282                         //
 283                         // Now we perform some checks on the positional args as they
 284                         // cannot be null for a constructor which expects a parameter
 285                         // of type object
 286                         //
 287
 288                         ParameterData pd = Invocation.GetParameterData (constructor);
 289
 290                         for (int j = 0; j < pos_arg_count; ++j) {
 291                                 Argument a = (Argument) pos_args [j];
 292
 293                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {
 294                                         Error_AttributeArgumentNotValid ();
 295                                         return null;
 296                                 }
 297                         }
 298
 299                         PropertyInfo [] prop_info_arr = new PropertyInfo [prop_infos.Count];
 300                         FieldInfo [] field_info_arr = new FieldInfo [field_infos.Count];
 301                         object [] field_values_arr = new object [field_values.Count];
 302                         object [] prop_values_arr = new object [prop_values.Count];
 303
 304                         field_infos.CopyTo  (field_info_arr, 0);
 305                         field_values.CopyTo (field_values_arr, 0);
 306
 307                         prop_values.CopyTo  (prop_values_arr, 0);
 308                         prop_infos.CopyTo   (prop_info_arr, 0);
 309
 310                         try {
 311                                 cb = new CustomAttributeBuilder (
 312                                         (ConstructorInfo) constructor, pos_values,
 313                                         prop_info_arr, prop_values_arr,
 314                                         field_info_arr, field_values_arr);
 315
 316                         } catch (NullReferenceException) {
 317                                 //
 318                                 // Don't know what to do here
 319                                 //
 320                         } catch {
 321                                 //
 322                                 // Sample:
 323                                 // using System.ComponentModel;
 324                                 // [DefaultValue (CollectionChangeAction.Add)]
 325                                 // class X { static void Main () {} }
 326                                 //
 327                                 Report.Warning (
 328                                         -23, Location,
 329                                         "The compiler can not encode this attribute in .NET due to\n" +
 330                                         "\ta bug in the .NET runtime.  Try the Mono runtime");
 331                         }
 332
 333                         return cb;
 334                 }
 335
 336                 static string GetValidPlaces (Attribute attr)
 337                 {
 338                         StringBuilder sb = new StringBuilder ();
 339                         AttributeTargets targets = 0;
 340
 341                         TypeContainer a = TypeManager.LookupAttr (attr.Type);
 342
 343                         if (a == null) {
 344
 345                                 System.Attribute [] attrs = null;
 346
 347                                 try {
 348                                         attrs = System.Attribute.GetCustomAttributes (attr.Type);
 349
 350                                 } catch {
 351                                         Report.Error (-20, attr.Location, "Cannot find attribute type " + attr.Name +
 352                                                       " (maybe you forgot to set the usage using the" +
 353                                                       " AttributeUsage attribute ?).");
 354                                         return null;
 355                                 }
 356
 357                                 foreach (System.Attribute tmp in attrs)
 358                                         if (tmp is AttributeUsageAttribute) {
 359                                                 targets = ((AttributeUsageAttribute) tmp).ValidOn;
 360                                                 break;
 361                                         }
 362                         } else
 363                                 targets = a.Targets;
 364
 365
 366                         if ((targets & AttributeTargets.Assembly) != 0)
 367                                 sb.Append ("'assembly' ");
 368
 369                         if ((targets & AttributeTargets.Class) != 0)
 370                                 sb.Append ("'class' ");
 371
 372                         if ((targets & AttributeTargets.Constructor) != 0)
 373                                 sb.Append ("'constructor' ");
 374
 375                         if ((targets & AttributeTargets.Delegate) != 0)
 376                                 sb.Append ("'delegate' ");
 377
 378                         if ((targets & AttributeTargets.Enum) != 0)
 379                                 sb.Append ("'enum' ");
 380
 381                         if ((targets & AttributeTargets.Event) != 0)
 382                                 sb.Append ("'event' ");
 383
 384                         if ((targets & AttributeTargets.Field) != 0)
 385                                 sb.Append ("'field' ");
 386
 387                         if ((targets & AttributeTargets.Interface) != 0)
 388                                 sb.Append ("'interface' ");
 389
 390                         if ((targets & AttributeTargets.Method) != 0)
 391                                 sb.Append ("'method' ");
 392
 393                         if ((targets & AttributeTargets.Module) != 0)
 394                                 sb.Append ("'module' ");
 395
 396                         if ((targets & AttributeTargets.Parameter) != 0)
 397                                 sb.Append ("'parameter' ");
 398
 399                         if ((targets & AttributeTargets.Property) != 0)
 400                                 sb.Append ("'property' ");
 401
 402                         if ((targets & AttributeTargets.ReturnValue) != 0)
 403                                 sb.Append ("'return value' ");
 404
 405                         if ((targets & AttributeTargets.Struct) != 0)
 406                                 sb.Append ("'struct' ");
 407
 408                         return sb.ToString ();
 409
 410                 }
 411
 412                 public static void Error_AttributeNotValidForElement (Attribute a, Location loc)
 413                 {
 414                         Report.Error (
 415                                 592, loc, "Attribute '" + a.Name +
 416                                 "' is not valid on this declaration type. " +
 417                                 "It is valid on " + GetValidPlaces (a) + "declarations only.");
 418                 }
 419
 420                 public static bool CheckAttribute (Attribute a, object element)
 421                 {
 422                         TypeContainer attr = TypeManager.LookupAttr (a.Type);
 423                         AttributeTargets targets = 0;
 424
 425
 426                         if (attr == null) {
 427
 428                                 System.Attribute [] attrs = null;
 429
 430                                 try {
 431                                         attrs = System.Attribute.GetCustomAttributes (a.Type);
 432
 433                                 } catch {
 434                                         Report.Error (-20, a.Location, "Cannot find attribute type " + a.Name +
 435                                                       " (maybe you forgot to set the usage using the" +
 436                                                       " AttributeUsage attribute ?).");
 437                                         return false;
 438                                 }
 439
 440                                 foreach (System.Attribute tmp in attrs)
 441                                         if (tmp is AttributeUsageAttribute)
 442                                                 targets = ((AttributeUsageAttribute) tmp).ValidOn;
 443                         } else
 444                                 targets = attr.Targets;
 445
 446                         if (element is Class) {
 447                                 if ((targets & AttributeTargets.Class) != 0)
 448                                         return true;
 449                                 else
 450                                         return false;
 451
 452                         } else if (element is Struct) {
 453                                 if ((targets & AttributeTargets.Struct) != 0)
 454                                         return true;
 455                                 else
 456                                         return false;
 457                         } else if (element is Constructor) {
 458                                 if ((targets & AttributeTargets.Constructor) != 0)
 459                                         return true;
 460                                 else
 461                                         return false;
 462                         } else if (element is Delegate) {
 463                                 if ((targets & AttributeTargets.Delegate) != 0)
 464                                         return true;
 465                                 else
 466                                         return false;
 467                         } else if (element is Enum) {
 468                                 if ((targets & AttributeTargets.Enum) != 0)
 469                                         return true;
 470                                 else
 471                                         return false;
 472                         } else if (element is Event || element is InterfaceEvent) {
 473                                 if ((targets & AttributeTargets.Event) != 0)
 474                                         return true;
 475                                 else
 476                                         return false;
 477                         } else if (element is Field || element is FieldBuilder) {
 478                                 if ((targets & AttributeTargets.Field) != 0)
 479                                         return true;
 480                                 else
 481                                         return false;
 482                         } else if (element is Interface) {
 483                                 if ((targets & AttributeTargets.Interface) != 0)
 484                                         return true;
 485                                 else
 486                                         return false;
 487                         } else if (element is Method || element is Operator || element is InterfaceMethod || element is Accessor) {
 488                                 if ((targets & AttributeTargets.Method) != 0)
 489                                         return true;
 490                                 else
 491                                         return false;
 492                         } else if (element is ParameterBuilder) {
 493                                 if ((targets & AttributeTargets.Parameter) != 0)
 494                                         return true;
 495                                 else
 496                                         return false;
 497                         } else if (element is Property || element is Indexer ||
 498                                    element is InterfaceProperty || element is InterfaceIndexer) {
 499                                 if ((targets & AttributeTargets.Property) != 0)
 500                                         return true;
 501                                 else
 502                                         return false;
 503                         } else if (element is AssemblyBuilder){
 504                                 if ((targets & AttributeTargets.Assembly) != 0)
 505                                         return true;
 506                                 else
 507                                         return false;
 508                         }
 509
 510                         return false;
 511                 }
 512
 513                 //
 514                 // This method should be invoked to pull the IndexerName attribute from an
 515                 // Indexer if it exists.
 516                 //
 517                 public static string ScanForIndexerName (EmitContext ec, Attributes opt_attrs)
 518                 {
 519                         if (opt_attrs == null)
 520                                 return null;
 521                         if (opt_attrs.AttributeSections == null)
 522                                 return null;
 523
 524                         foreach (AttributeSection asec in opt_attrs.AttributeSections) {
 525                                 if (asec.Attributes == null)
 526                                         continue;
 527
 528                                 foreach (Attribute a in asec.Attributes){
 529                                         if (a.ResolveType (ec) == null)
 530                                                 return null;
 531
 532                                         if (a.Type != TypeManager.indexer_name_type)
 533                                                 continue;
 534
 535                                         //
 536                                         // So we have found an IndexerName, pull the data out.
 537                                         //
 538                                         if (a.Arguments == null || a.Arguments [0] == null){
 539                                                 Error_AttributeConstructorMismatch (a.Location);
 540                                                 return null;
 541                                         }
 542                                         ArrayList pos_args = (ArrayList) a.Arguments [0];
 543                                         if (pos_args.Count == 0){
 544                                                 Error_AttributeConstructorMismatch (a.Location);
 545                                                 return null;
 546                                         }
 547
 548                                         Argument arg = (Argument) pos_args [0];
 549                                         if (!arg.Resolve (ec, a.Location))
 550                                                 return null;
 551
 552                                         Expression e = arg.Expr;
 553                                         if (!(e is StringConstant)){
 554                                                 Error_AttributeConstructorMismatch (a.Location);
 555                                                 return null;
 556                                         }
 557
 558                                         //
 559                                         // Remove the attribute from the list
 560                                         //
 561                                         asec.Attributes.Remove (a);
 562
 563                                         return (((StringConstant) e).Value);
 564                                 }
 565                         }
 566                         return null;
 567                 }
 568
 569                 //
 570                 // This pulls the condition name out of a Conditional attribute
 571                 //
 572                 public string Conditional_GetConditionName ()
 573                 {
 574                         //
 575                         // So we have a Conditional, pull the data out.
 576                         //
 577                         if (Arguments == null || Arguments [0] == null){
 578                                 Error_AttributeConstructorMismatch (Location);
 579                                 return null;
 580                         }
 581
 582                         ArrayList pos_args = (ArrayList) Arguments [0];
 583                         if (pos_args.Count != 1){
 584                                 Error_AttributeConstructorMismatch (Location);
 585                                 return null;
 586                         }
 587
 588                         Argument arg = (Argument) pos_args [0];
 589                         if (!(arg.Expr is StringConstant)){
 590                                 Error_AttributeConstructorMismatch (Location);
 591                                 return null;
 592                         }
 593
 594                         return ((StringConstant) arg.Expr).Value;
 595                 }
 596
 597                 //
 598                 // This pulls the obsolete message and error flag out of an Obsolete attribute
 599                 //
 600                 public string Obsolete_GetObsoleteMessage (out bool is_error)
 601                 {
 602                         is_error = false;
 603                         //
 604                         // So we have an Obsolete, pull the data out.
 605                         //
 606                         if (Arguments == null || Arguments [0] == null)
 607                                 return "";
 608
 609                         ArrayList pos_args = (ArrayList) Arguments [0];
 610                         if (pos_args.Count == 0)
 611                                 return "";
 612                         else if (pos_args.Count > 2){
 613                                 Error_AttributeConstructorMismatch (Location);
 614                                 return null;
 615                         }
 616
 617                         Argument arg = (Argument) pos_args [0];
 618                         if (!(arg.Expr is StringConstant)){
 619                                 Error_AttributeConstructorMismatch (Location);
 620                                 return null;
 621                         }
 622
 623                         if (pos_args.Count == 2){
 624                                 Argument arg2 = (Argument) pos_args [1];
 625                                 if (!(arg2.Expr is BoolConstant)){
 626                                         Error_AttributeConstructorMismatch (Location);
 627                                         return null;
 628                                 }
 629                                 is_error = ((BoolConstant) arg2.Expr).Value;
 630                         }
 631
 632                         return ((StringConstant) arg.Expr).Value;
 633                 }
 634
 635                 //
 636                 // Applies the attributes to the `builder'.
 637                 //
 638                 public static void ApplyAttributes (EmitContext ec, object builder, object kind,
 639                                                     Attributes opt_attrs, Location loc)
 640                 {
 641                         if (opt_attrs == null)
 642                                 return;
 643                         if (opt_attrs.AttributeSections == null)
 644                                 return;
 645
 646                         foreach (AttributeSection asec in opt_attrs.AttributeSections) {
 647                                 if (asec.Attributes == null)
 648                                         continue;
 649
 650                                 if (asec.Target == "assembly" && !(builder is AssemblyBuilder))
 651                                         continue;
 652
 653                                 foreach (Attribute a in asec.Attributes) {
 654                                         CustomAttributeBuilder cb = a.Resolve (ec);
 655
 656                                         if (cb == null)
 657                                                 continue;
 658
 659                                         if (!(kind is TypeContainer))
 660                                                 if (!CheckAttribute (a, kind)) {
 661                                                         Error_AttributeNotValidForElement (a, loc);
 662                                                         return;
 663                                                 }
 664
 665                                         if (kind is Method || kind is Operator || kind is InterfaceMethod ||
 666                                             kind is Accessor) {
 667                                                 if (a.Type == TypeManager.methodimpl_attr_type) {
 668                                                         if (a.ImplOptions == MethodImplOptions.InternalCall)
 669                                                                 ((MethodBuilder) builder).
 670                                                                 SetImplementationFlags (
 671                                                                         MethodImplAttributes.InternalCall |
 672                                                                         MethodImplAttributes.Runtime);
 673                                                 } else if (a.Type != TypeManager.dllimport_type){
 674                                                         ((MethodBuilder) builder).SetCustomAttribute (cb);
 675                                                 }
 676                                         } else if (kind is Constructor) {
 677                                                 ((ConstructorBuilder) builder).SetCustomAttribute (cb);
 678                                         } else if (kind is Field) {
 679                                                 ((FieldBuilder) builder).SetCustomAttribute (cb);
 680                                         } else if (kind is Property || kind is Indexer ||
 681                                                    kind is InterfaceProperty || kind is InterfaceIndexer) {
 682                                                 ((PropertyBuilder) builder).SetCustomAttribute (cb);
 683                                         } else if (kind is Event || kind is InterfaceEvent) {
 684                                                 ((MyEventBuilder) builder).SetCustomAttribute (cb);
 685                                         } else if (kind is ParameterBuilder) {
 686
 687                                                 if (a.Type == TypeManager.marshal_as_attr_type) {
 688                                                         UnmanagedMarshal marshal =
 689                                                                 UnmanagedMarshal.DefineUnmanagedMarshal (a.UnmanagedType);
 690
 691                                                         ((ParameterBuilder) builder).SetMarshal (marshal);
 692                                                 } else
 693                                                         ((ParameterBuilder) builder).SetCustomAttribute (cb);
 694
 695                                         } else if (kind is Enum) {
 696                                                 ((TypeBuilder) builder).SetCustomAttribute (cb);
 697
 698                                         } else if (kind is TypeContainer) {
 699                                                 TypeContainer tc = (TypeContainer) kind;
 700
 701                                                 if (a.UsageAttr) {
 702                                                         tc.Targets = a.Targets;
 703                                                         tc.AllowMultiple = a.AllowMultiple;
 704                                                         tc.Inherited = a.Inherited;
 705
 706                                                 } else if (a.Type == TypeManager.default_member_type) {
 707                                                         if (tc.Indexers != null) {
 708                                                                 Report.Error (646, loc,
 709                                                                       "Cannot specify the DefaultMember attribute on" +
 710                                                                       " a type containing an indexer");
 711                                                                 return;
 712                                                         }
 713
 714                                                 } else {
 715                                                         if (!CheckAttribute (a, kind)) {
 716                                                                 Error_AttributeNotValidForElement (a, loc);
 717                                                                 return;
 718                                                         }
 719                                                 }
 720
 721                                                 try {
 722                                                         ((TypeBuilder) builder).SetCustomAttribute (cb);
 723                                                 } catch (System.ArgumentException) {
 724                                                         Report.Warning (
 725                                                                 -21, loc,
 726                                                 "The CharSet named property on StructLayout\n"+
 727                                                 "\tdoes not work correctly on Microsoft.NET\n"+
 728                                                 "\tYou might want to remove the CharSet declaration\n"+
 729                                                 "\tor compile using the Mono runtime instead of the\n"+
 730                                                 "\tMicrosoft .NET runtime");
 731                                                 }
 732
 733                                         } else if (kind is Interface) {
 734                                                 Interface iface = (Interface) kind;
 735
 736                                                 if ((a.Type == TypeManager.default_member_type) &&
 737                                                     (iface.InterfaceIndexers != null)) {
 738                                                         Report.Error (
 739                                                                 646, loc,
 740                                                                 "Cannot specify the DefaultMember attribute on" +
 741                                                                 " a type containing an indexer");
 742                                                         return;
 743                                                 }
 744
 745                                                 if (!CheckAttribute (a, kind)) {
 746                                                         Error_AttributeNotValidForElement (a, loc);
 747                                                         return;
 748                                                 }
 749
 750                                                 ((TypeBuilder) builder).SetCustomAttribute (cb);
 751                                         } else if (kind is AssemblyBuilder){
 752                                                 ((AssemblyBuilder) builder).SetCustomAttribute (cb);
 753                                         } else if (kind is ModuleBuilder) {
 754                                                 ((ModuleBuilder) builder).SetCustomAttribute (cb);
 755                                         } else if (kind is FieldBuilder) {
 756                                                 ((FieldBuilder) builder).SetCustomAttribute (cb);
 757                                         } else
 758                                                 throw new Exception ("Unknown kind: " + kind);
 759                                 }
 760                         }
 761                 }
 762
 763                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,
 764                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
 765                 {
 766                         //
 767                         // We extract from the attribute the information we need
 768                         //
 769
 770                         if (Arguments == null) {
 771                                 Console.WriteLine ("Internal error : this is not supposed to happen !");
 772                                 return null;
 773                         }
 774
 775                         Type = CheckAttributeType (ec);
 776                         if (Type == null)
 777                                 return null;
 778
 779                         ArrayList named_args = new ArrayList ();
 780
 781                         ArrayList pos_args = (ArrayList) Arguments [0];
 782                         if (Arguments.Count > 1)
 783                                 named_args = (ArrayList) Arguments [1];
 784
 785
 786                         string dll_name = null;
 787
 788                         Argument tmp = (Argument) pos_args [0];
 789
 790                         if (!tmp.Resolve (ec, Location))
 791                                 return null;
 792
 793                         if (tmp.Expr is Constant)
 794                                 dll_name = (string) ((Constant) tmp.Expr).GetValue ();
 795                         else {
 796                                 Error_AttributeArgumentNotValid ();
 797                                 return null;
 798                         }
 799
 800                         // Now we process the named arguments
 801                         CallingConvention cc = CallingConvention.Winapi;
 802                         CharSet charset = CharSet.Ansi;
 803                         bool preserve_sig = true;
 804                         bool exact_spelling = false;
 805                         bool set_last_err = false;
 806                         string entry_point = null;
 807
 808                         for (int i = 0; i < named_args.Count; i++) {
 809
 810                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 811
 812                                 string member_name = (string) de.Key;
 813                                 Argument a  = (Argument) de.Value;
 814
 815                                 if (!a.Resolve (ec, Location))
 816                                         return null;
 817
 818                                 Expression member = Expression.MemberLookup (
 819                                         ec, Type, member_name,
 820                                         MemberTypes.Field | MemberTypes.Property,
 821                                         BindingFlags.Public | BindingFlags.Instance,
 822                                         Location);
 823
 824                                 if (member == null || !(member is FieldExpr)) {
 825                                         Error_InvalidNamedArgument (member_name);
 826                                         return null;
 827                                 }
 828
 829                                 if (member is FieldExpr) {
 830                                         FieldExpr fe = (FieldExpr) member;
 831                                         FieldInfo fi = fe.FieldInfo;
 832
 833                                         if (fi.IsInitOnly) {
 834                                                 Error_InvalidNamedArgument (member_name);
 835                                                 return null;
 836                                         }
 837
 838                                         if (a.Expr is Constant) {
 839                                                 Constant c = (Constant) a.Expr;
 840
 841                                                 if (member_name == "CallingConvention")
 842                                                         cc = (CallingConvention) c.GetValue ();
 843                                                 else if (member_name == "CharSet")
 844                                                         charset = (CharSet) c.GetValue ();
 845                                                 else if (member_name == "EntryPoint")
 846                                                         entry_point = (string) c.GetValue ();
 847                                                 else if (member_name == "SetLastError")
 848                                                         set_last_err = (bool) c.GetValue ();
 849                                                 else if (member_name == "ExactSpelling")
 850                                                         exact_spelling = (bool) c.GetValue ();
 851                                                 else if (member_name == "PreserveSig")
 852                                                         preserve_sig = (bool) c.GetValue ();
 853                                         } else {
 854                                                 Error_AttributeArgumentNotValid ();
 855                                                 return null;
 856                                         }
 857
 858                                 }
 859                         }
 860
 861                         if (entry_point == null)
 862                                 entry_point = name;
 863
 864                         MethodBuilder mb = builder.DefinePInvokeMethod (
 865                                 name, dll_name, entry_point, flags | MethodAttributes.HideBySig,
 866                                 CallingConventions.Standard,
 867                                 ret_type,
 868                                 param_types,
 869                                 cc,
 870                                 charset);
 871
 872                         if (preserve_sig)
 873                                 mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
 874
 875                         return mb;
 876                 }
 877         }
 878
 879         public class AttributeSection {
 880
 881                 public readonly string    Target;
 882                 public readonly ArrayList Attributes;
 883
 884                 public AttributeSection (string target, ArrayList attrs)
 885                 {
 886                         Target = target;
 887                         Attributes = attrs;
 888                 }
 889
 890         }
 891
 892         public class Attributes {
 893                 public ArrayList AttributeSections;
 894                 public Location Location;
 895
 896                 public Attributes (AttributeSection a, Location loc)
 897                 {
 898                         AttributeSections = new ArrayList ();
 899                         AttributeSections.Add (a);
 900
 901                 }
 902
 903                 public void AddAttribute (AttributeSection a)
 904                 {
 905                         if (a != null)
 906                                 AttributeSections.Add (a);
 907                 }
 908
 909                 public void AddAttributeSection (AttributeSection a)
 910                 {
 911                         if (a != null && !AttributeSections.Contains (a))
 912                                 AttributeSections.Add (a);
 913                 }
 914
 915                 public bool Contains (Type t)
 916                 {
 917                         foreach (AttributeSection attr_section in AttributeSections){
 918                                 foreach (Attribute a in attr_section.Attributes){
 919                                         if (a.Type == t)
 920                                                 return true;
 921                                 }
 922                         }
 923                         return false;
 924                 }
 925         }
 926 }