mcs/gmcs/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.Collections.Specialized;
  16 using System.Reflection;
  17 using System.Reflection.Emit;
  18 using System.Runtime.InteropServices;
  19 using System.Runtime.CompilerServices;
  20 using System.Text;
  21
  22 namespace Mono.CSharp {
  23
  24         /// <summary>
  25         ///   Base class for objects that can have Attributes applied to them.
  26         /// </summary>
  27         public abstract class Attributable {
  28                 /// <summary>
  29                 ///   Attributes for this type
  30                 /// </summary>
  31                 Attributes attributes;
  32
  33                 public Attributable(Attributes attrs)
  34                 {
  35                         attributes = attrs;
  36                         if (attributes != null)
  37                                 attributes.CheckTargets (ValidAttributeTargets);
  38                 }
  39
  40                 public Attributes OptAttributes
  41                 {
  42                         get {
  43                                 return attributes;
  44                         }
  45                         set {
  46                                 attributes = value;
  47                         }
  48                 }
  49
  50                 /// <summary>
  51                 /// Use member-specific procedure to apply attribute @a in @cb to the entity being built in @builder
  52                 /// </summary>
  53                 public abstract void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb);
  54
  55                 /// <summary>
  56                 /// Returns combination of enabled AttributeTargets
  57                 /// </summary>
  58                 public abstract AttributeTargets AttributeTargets { get; }
  59
  60                 public abstract bool IsClsCompliaceRequired (DeclSpace ds);
  61
  62                 /// <summary>
  63                 /// Gets list of valid attribute targets for explicit target declaration
  64                 /// </summary>
  65                 protected abstract string[] ValidAttributeTargets { get; }
  66         };
  67
  68         public class Attribute {
  69                 public readonly string Target;
  70                 public readonly string    Name;
  71                 public readonly ArrayList Arguments;
  72
  73                 public readonly Location Location;
  74
  75                 public Type Type;
  76
  77                 // Is non-null if type is AttributeUsageAttribute
  78                 AttributeUsageAttribute usage_attribute;
  79
  80                 public AttributeUsageAttribute UsageAttribute {
  81                         get {
  82                                 return usage_attribute;
  83                         }
  84                 }
  85
  86                 MethodImplOptions ImplOptions;
  87                 UnmanagedType     UnmanagedType;
  88                 CustomAttributeBuilder cb;
  89
  90                 // non-null if named args present after Resolve () is called
  91                 PropertyInfo [] prop_info_arr;
  92                 FieldInfo [] field_info_arr;
  93                 object [] field_values_arr;
  94                 object [] prop_values_arr;
  95                 object [] pos_values;
  96
  97                 static PtrHashtable usage_attr_cache = new PtrHashtable ();
  98
  99                 public Attribute (string target, string name, ArrayList args, Location loc)
 100                 {
 101                         Name = name;
 102                         Arguments = args;
 103                         Location = loc;
 104                         Target = target;
 105                 }
 106
 107                 void Error_InvalidNamedArgument (string name)
 108                 {
 109                         Report.Error (617, Location, "'" + name + "' is not a valid named attribute " +
 110                                       "argument. Named attribute arguments must be fields which are not " +
 111                                       "readonly, static or const, or properties with a set accessor which "+
 112                                       "are not static.");
 113                 }
 114
 115                 static void Error_AttributeArgumentNotValid (Location loc)
 116                 {
 117                         Report.Error (182, loc,
 118                                       "An attribute argument must be a constant expression, typeof " +
 119                                       "expression or array creation expression");
 120                 }
 121
 122                 void Error_AttributeConstructorMismatch ()
 123                 {
 124                         Report.Error (-6, Location,
 125                                       "Could not find a constructor for this argument list.");
 126                 }
 127
 128                 static void Error_TypeParameterInAttribute (Location loc)
 129                 {
 130                         Report.Error (
 131                                 -202, loc, "Can not use a type parameter in an attribute");
 132                 }
 133
 134                 /// <summary>
 135                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 136                 /// </summary>
 137                 protected virtual Type CheckAttributeType (EmitContext ec, bool complain)
 138                 {
 139                         TypeExpr t1 = RootContext.LookupType (ec.DeclSpace, Name, true, Location);
 140                         // FIXME: Shouldn't do this for quoted attributes: [@A]
 141                         TypeExpr t2 = RootContext.LookupType (ec.DeclSpace, Name + "Attribute", true, Location);
 142
 143                         String err0616 = null;
 144                         if (t1 != null && ! t1.IsAttribute) {
 145                                 t1 = null;
 146                                 err0616 = "'" + Name + "': is not an attribute class";
 147                         }
 148                         if (t2 != null && ! t2.IsAttribute) {
 149                                 t2 = null;
 150                                 err0616 = (err0616 != null)
 151                                         ? "Neither '" + Name + "' nor '" + Name + "Attribute' is an attribute class"
 152                                         : "'" + Name + "Attribute': is not an attribute class";
 153                         }
 154
 155                         if (t1 != null && t2 != null) {
 156                                 Report.Error(1614, Location, "'" + Name + "': is ambiguous; "
 157                                              + " use either '@" + Name + "' or '" + Name + "Attribute'");
 158                                 return null;
 159                         }
 160                         if (t1 != null)
 161                                 return t1.ResolveType (ec);
 162                         if (t2 != null)
 163                                 return t2.ResolveType (ec);
 164                         if (err0616 != null) {
 165                                 Report.Error (616, Location, err0616);
 166                                 return null;
 167                         }
 168
 169                         if (complain)
 170                                 Report.Error (246, Location,
 171                                               "Could not find attribute '" + Name
 172                                               + "' (are you missing a using directive or an assembly reference ?)");
 173                         return null;
 174                 }
 175
 176                 public Type ResolveType (EmitContext ec, bool complain)
 177                 {
 178                         if (Type == null)
 179                                 Type = CheckAttributeType (ec, complain);
 180                         return Type;
 181                 }
 182
 183                 /// <summary>
 184                 ///   Validates the guid string
 185                 /// </summary>
 186                 bool ValidateGuid (string guid)
 187                 {
 188                         try {
 189                                 new Guid (guid);
 190                                 return true;
 191                         } catch {
 192                                 Report.Error (647, Location, "Format of GUID is invalid: " + guid);
 193                                 return false;
 194                         }
 195                 }
 196
 197                 //
 198                 // Given an expression, if the expression is a valid attribute-argument-expression
 199                 // returns an object that can be used to encode it, or null on failure.
 200                 //
 201                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, out object result)
 202                 {
 203                         if (e is Constant) {
 204                                 result = ((Constant) e).GetValue ();
 205                                 return true;
 206                         } else if (e is TypeOf) {
 207                                 result = ((TypeOf) e).TypeArg;
 208                                 return true;
 209                         } else if (e is ArrayCreation){
 210                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();
 211                                 if (result != null)
 212                                         return true;
 213                         } else if (e is EmptyCast) {
 214                                 result = e;
 215                                 if (((EmptyCast) e).Child is Constant) {
 216                                         result = ((Constant) ((EmptyCast)e).Child).GetValue();
 217                                 }
 218                                 return true;
 219                         }
 220
 221                         result = null;
 222                         Error_AttributeArgumentNotValid (loc);
 223                         return false;
 224                 }
 225
 226                 public CustomAttributeBuilder Resolve (EmitContext ec)
 227                 {
 228                         Type oldType = Type;
 229
 230                         // Sanity check.
 231                         Type = CheckAttributeType (ec, true);
 232                         if (oldType == null && Type == null)
 233                                 return null;
 234                         if (oldType != null && oldType != Type) {
 235                                 Report.Error (-6, Location,
 236                                               "Attribute {0} resolved to different types at different times: {1} vs. {2}",
 237                                               Name, oldType, Type);
 238                                 return null;
 239                         }
 240
 241                         bool MethodImplAttr = false;
 242                         bool MarshalAsAttr = false;
 243                         bool GuidAttr = false;
 244                         bool usage_attr = false;
 245
 246                         bool DoCompares = true;
 247
 248                         //
 249                         // If we are a certain special attribute, we
 250                         // set the information accordingly
 251                         //
 252
 253                         if (Type == TypeManager.attribute_usage_type)
 254                                 usage_attr = true;
 255                         else if (Type == TypeManager.methodimpl_attr_type)
 256                                 MethodImplAttr = true;
 257                         else if (Type == TypeManager.marshal_as_attr_type)
 258                                 MarshalAsAttr = true;
 259                         else if (Type == TypeManager.guid_attr_type)
 260                                 GuidAttr = true;
 261                         else
 262                                 DoCompares = false;
 263
 264                         // Now we extract the positional and named arguments
 265
 266                         ArrayList pos_args = new ArrayList ();
 267                         ArrayList named_args = new ArrayList ();
 268                         int pos_arg_count = 0;
 269
 270                         if (Arguments != null) {
 271                                 pos_args = (ArrayList) Arguments [0];
 272                                 if (pos_args != null)
 273                                         pos_arg_count = pos_args.Count;
 274                                 if (Arguments.Count > 1)
 275                                         named_args = (ArrayList) Arguments [1];
 276                         }
 277
 278                         pos_values = new object [pos_arg_count];
 279
 280                         //
 281                         // First process positional arguments
 282                         //
 283
 284                         int i;
 285                         for (i = 0; i < pos_arg_count; i++) {
 286                                 Argument a = (Argument) pos_args [i];
 287                                 Expression e;
 288
 289                                 if (!a.Resolve (ec, Location))
 290                                         return null;
 291
 292                                 e = a.Expr;
 293
 294                                 object val;
 295                                 if (!GetAttributeArgumentExpression (e, Location, out val))
 296                                         return null;
 297
 298                                 pos_values [i] = val;
 299                                 if (DoCompares){
 300                                         if (usage_attr)
 301                                                 usage_attribute = new AttributeUsageAttribute ((AttributeTargets) pos_values [0]);
 302                                         else if (MethodImplAttr)
 303                                                 this.ImplOptions = (MethodImplOptions) pos_values [0];
 304                                         else if (GuidAttr){
 305                                                 //
 306                                                 // we will later check the validity of the type
 307                                                 //
 308                                                 if (pos_values [0] is string){
 309                                                         if (!ValidateGuid ((string) pos_values [0]))
 310                                                                 return null;
 311                                                 }
 312
 313                                         } else if (MarshalAsAttr)
 314                                                 this.UnmanagedType =
 315                                                 (System.Runtime.InteropServices.UnmanagedType) pos_values [0];
 316                                 }
 317                         }
 318
 319                         //
 320                         // Now process named arguments
 321                         //
 322
 323                         ArrayList field_infos = null;
 324                         ArrayList prop_infos  = null;
 325                         ArrayList field_values = null;
 326                         ArrayList prop_values = null;
 327
 328                         if (named_args.Count > 0) {
 329                                 field_infos = new ArrayList ();
 330                                 prop_infos  = new ArrayList ();
 331                                 field_values = new ArrayList ();
 332                                 prop_values = new ArrayList ();
 333                         }
 334
 335                         Hashtable seen_names = new Hashtable();
 336
 337                         for (i = 0; i < named_args.Count; i++) {
 338                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 339                                 string member_name = (string) de.Key;
 340                                 Argument a  = (Argument) de.Value;
 341                                 Expression e;
 342
 343                                 if (seen_names.Contains(member_name)) {
 344                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 345                                         return null;
 346                                 }
 347                                 seen_names.Add(member_name, 1);
 348
 349                                 if (!a.Resolve (ec, Location))
 350                                         return null;
 351
 352                                 Expression member = Expression.MemberLookup (
 353                                         ec, Type, member_name,
 354                                         MemberTypes.Field | MemberTypes.Property,
 355                                         BindingFlags.Public | BindingFlags.Instance,
 356                                         Location);
 357
 358                                 if (member == null || !(member is PropertyExpr || member is FieldExpr)) {
 359                                         Error_InvalidNamedArgument (member_name);
 360                                         return null;
 361                                 }
 362
 363                                 e = a.Expr;
 364                                 if (e is TypeParameterExpr){
 365                                         Error_TypeParameterInAttribute (Location);
 366                                         return null;
 367                                 }
 368
 369                                 if (member is PropertyExpr) {
 370                                         PropertyExpr pe = (PropertyExpr) member;
 371                                         PropertyInfo pi = pe.PropertyInfo;
 372
 373                                         if (!pi.CanWrite) {
 374                                                 Error_InvalidNamedArgument (member_name);
 375                                                 return null;
 376                                         }
 377
 378                                         if (e is Constant) {
 379                                                 Constant c;
 380
 381                                                 if (e.Type != pi.PropertyType){
 382                                                         c = Const.ChangeType (Location, (Constant) e, pi.PropertyType);
 383                                                         if (c == null)
 384                                                                 return null;
 385                                                 } else
 386                                                         c = (Constant) e;
 387
 388                                                 object o = c.GetValue ();
 389                                                 prop_values.Add (o);
 390
 391                                                 if (usage_attribute != null) {
 392                                                         if (member_name == "AllowMultiple")
 393                                                                 usage_attribute.AllowMultiple = (bool) o;
 394                                                         if (member_name == "Inherited")
 395                                                                 usage_attribute.Inherited = (bool) o;
 396                                                 }
 397
 398                                         } else if (e is TypeOf) {
 399                                                 prop_values.Add (((TypeOf) e).TypeArg);
 400                                         } else if (e is ArrayCreation) {
 401                                                 prop_values.Add (((ArrayCreation) e).EncodeAsAttribute());
 402                                         } else {
 403                                                 Error_AttributeArgumentNotValid (Location);
 404                                                 return null;
 405                                         }
 406
 407                                         prop_infos.Add (pi);
 408
 409                                 } else if (member is FieldExpr) {
 410                                         FieldExpr fe = (FieldExpr) member;
 411                                         FieldInfo fi = fe.FieldInfo;
 412
 413                                         if (fi.IsInitOnly) {
 414                                                 Error_InvalidNamedArgument (member_name);
 415                                                 return null;
 416                                         }
 417
 418                                         //
 419                                         // Handle charset here, and set the TypeAttributes
 420
 421                                         if (e is Constant){
 422                                                 Constant c = (Constant) e;;
 423
 424                                                 if (c.Type != fi.FieldType){
 425                                                         c = Const.ChangeType (Location, (Constant) e, fi.FieldType);
 426                                                         if (c == null)
 427                                                                 return null;
 428                                                 }
 429
 430                                                 object value = c.GetValue ();
 431                                                 field_values.Add (value);
 432                                         } else if (e is TypeOf) {
 433                                                 field_values.Add (((TypeOf) e).TypeArg);
 434                                         } else {
 435                                                 Error_AttributeArgumentNotValid (Location);
 436                                                 return null;
 437                                         }
 438
 439                                         field_infos.Add (fi);
 440                                 }
 441                         }
 442
 443                         Expression mg = Expression.MemberLookup (
 444                                 ec, Type, ".ctor", MemberTypes.Constructor,
 445                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 446                                 Location);
 447
 448                         if (mg == null) {
 449                                 Error_AttributeConstructorMismatch ();
 450                                 return null;
 451                         }
 452
 453                         MethodBase constructor = Invocation.OverloadResolve (
 454                                 ec, (MethodGroupExpr) mg, pos_args, false, Location);
 455
 456                         if (constructor == null) {
 457                                 Error_AttributeConstructorMismatch ();
 458                                 return null;
 459                         }
 460
 461                         //
 462                         // Now we perform some checks on the positional args as they
 463                         // cannot be null for a constructor which expects a parameter
 464                         // of type object
 465                         //
 466
 467                         ParameterData pd = Invocation.GetParameterData (constructor);
 468
 469                         int group_in_params_array = Int32.MaxValue;
 470                         int pc = pd.Count;
 471                         if (pc > 0 && pd.ParameterModifier (pc-1) == Parameter.Modifier.PARAMS)
 472                                 group_in_params_array = pc-1;
 473
 474                         for (int j = 0; j < pos_arg_count; ++j) {
 475                                 Argument a = (Argument) pos_args [j];
 476
 477                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {
 478                                         Error_AttributeArgumentNotValid (Location);
 479                                         return null;
 480                                 }
 481
 482                                 if (j < group_in_params_array)
 483                                         continue;
 484
 485                                 if (j == group_in_params_array){
 486                                         object v = pos_values [j];
 487                                         int count = pos_arg_count - j;
 488
 489                                         object [] array = new object [count];
 490                                         pos_values [j] = array;
 491                                         array [0] = v;
 492                                 } else {
 493                                         object [] array = (object []) pos_values [group_in_params_array];
 494
 495                                         array [j - group_in_params_array] = pos_values [j];
 496                                 }
 497                         }
 498
 499                         //
 500                         // Adjust the size of the pos_values if it had params
 501                         //
 502                         if (group_in_params_array != Int32.MaxValue){
 503                                 int argc = group_in_params_array+1;
 504                                 object [] new_pos_values = new object [argc];
 505
 506                                 for (int p = 0; p < argc; p++)
 507                                         new_pos_values [p] = pos_values [p];
 508                                 pos_values = new_pos_values;
 509                         }
 510
 511                         try {
 512                                 if (named_args.Count > 0) {
 513                                         prop_info_arr = new PropertyInfo [prop_infos.Count];
 514                                         field_info_arr = new FieldInfo [field_infos.Count];
 515                                         field_values_arr = new object [field_values.Count];
 516                                         prop_values_arr = new object [prop_values.Count];
 517
 518                                         field_infos.CopyTo  (field_info_arr, 0);
 519                                         field_values.CopyTo (field_values_arr, 0);
 520
 521                                         prop_values.CopyTo  (prop_values_arr, 0);
 522                                         prop_infos.CopyTo   (prop_info_arr, 0);
 523
 524                                         cb = new CustomAttributeBuilder (
 525                                                 (ConstructorInfo) constructor, pos_values,
 526                                                 prop_info_arr, prop_values_arr,
 527                                                 field_info_arr, field_values_arr);
 528                                 }
 529                                 else
 530                                         cb = new CustomAttributeBuilder (
 531                                                 (ConstructorInfo) constructor, pos_values);
 532                         } catch (NullReferenceException) {
 533                                 //
 534                                 // Don't know what to do here
 535                                 //
 536                                 Report.Warning (
 537                                         -101, Location, "NullReferenceException while trying to create attribute." +
 538                                         "Something's wrong!");
 539                         } catch (Exception e) {
 540                                 //
 541                                 // Sample:
 542                                 // using System.ComponentModel;
 543                                 // [DefaultValue (CollectionChangeAction.Add)]
 544                                 // class X { static void Main () {} }
 545                                 //
 546                                 Report.Warning (
 547                                         -23, Location,
 548                                         "The compiler can not encode this attribute in .NET due to\n" +
 549                                         "\ta bug in the .NET runtime.  Try the Mono runtime.\nThe error was: " + e.Message);
 550                         }
 551
 552                         return cb;
 553                 }
 554
 555                 /// <summary>
 556                 ///   Get a string containing a list of valid targets for the attribute 'attr'
 557                 /// </summary>
 558                 static string GetValidTargets (Attribute attr)
 559                 {
 560                         StringBuilder sb = new StringBuilder ();
 561                         AttributeTargets targets = attr.GetAttributeUsage ().ValidOn;
 562
 563                         if ((targets & AttributeTargets.Assembly) != 0)
 564                                 sb.Append ("'assembly' ");
 565
 566                         if ((targets & AttributeTargets.Class) != 0)
 567                                 sb.Append ("'class' ");
 568
 569                         if ((targets & AttributeTargets.Constructor) != 0)
 570                                 sb.Append ("'constructor' ");
 571
 572                         if ((targets & AttributeTargets.Delegate) != 0)
 573                                 sb.Append ("'delegate' ");
 574
 575                         if ((targets & AttributeTargets.Enum) != 0)
 576                                 sb.Append ("'enum' ");
 577
 578                         if ((targets & AttributeTargets.Event) != 0)
 579                                 sb.Append ("'event' ");
 580
 581                         if ((targets & AttributeTargets.Field) != 0)
 582                                 sb.Append ("'field' ");
 583
 584                         if ((targets & AttributeTargets.Interface) != 0)
 585                                 sb.Append ("'interface' ");
 586
 587                         if ((targets & AttributeTargets.Method) != 0)
 588                                 sb.Append ("'method' ");
 589
 590                         if ((targets & AttributeTargets.Module) != 0)
 591                                 sb.Append ("'module' ");
 592
 593                         if ((targets & AttributeTargets.Parameter) != 0)
 594                                 sb.Append ("'parameter' ");
 595
 596                         if ((targets & AttributeTargets.Property) != 0)
 597                                 sb.Append ("'property' ");
 598
 599                         if ((targets & AttributeTargets.ReturnValue) != 0)
 600                                 sb.Append ("'return' ");
 601
 602                         if ((targets & AttributeTargets.Struct) != 0)
 603                                 sb.Append ("'struct' ");
 604
 605                         return sb.ToString ();
 606
 607                 }
 608
 609                 public static void Error_AttributeNotValidForElement (Attribute a, Location loc)
 610                 {
 611                         Report.Error (
 612                                 592, loc, "Attribute '" + a.Name +
 613                                 "' is not valid on this declaration type. " +
 614                                 "It is valid on " + GetValidTargets (a) + "declarations only.");
 615                 }
 616
 617
 618                 /// <summary>
 619                 /// Returns AttributeUsage attribute for this type
 620                 /// </summary>
 621                 public AttributeUsageAttribute GetAttributeUsage ()
 622                 {
 623                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 624                         if (ua != null)
 625                                 return ua;
 626
 627                         Class attr_class = TypeManager.LookupClass (Type);
 628
 629                         if (attr_class == null) {
 630                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 631                                 ua = (AttributeUsageAttribute)usage_attr [0];
 632                                 usage_attr_cache.Add (Type, ua);
 633                                 return ua;
 634                         }
 635
 636                         return attr_class.AttributeUsage;
 637                 }
 638
 639
 640                 //
 641                 // This pulls the condition name out of a Conditional attribute
 642                 //
 643                 public string Conditional_GetConditionName ()
 644                 {
 645                         //
 646                         // So we have a Conditional, pull the data out.
 647                         //
 648                         if (Arguments == null || Arguments [0] == null){
 649                                 Error_AttributeConstructorMismatch ();
 650                                 return null;
 651                         }
 652
 653                         ArrayList pos_args = (ArrayList) Arguments [0];
 654                         if (pos_args.Count != 1){
 655                                 Error_AttributeConstructorMismatch ();
 656                                 return null;
 657                         }
 658
 659                         Argument arg = (Argument) pos_args [0];
 660                         if (!(arg.Expr is StringConstant)){
 661                                 Error_AttributeConstructorMismatch ();
 662                                 return null;
 663                         }
 664
 665                         return ((StringConstant) arg.Expr).Value;
 666                 }
 667
 668                 //
 669                 // This pulls the obsolete message and error flag out of an Obsolete attribute
 670                 //
 671                 public string Obsolete_GetObsoleteMessage (out bool is_error)
 672                 {
 673                         is_error = false;
 674                         //
 675                         // So we have an Obsolete, pull the data out.
 676                         //
 677                         if (Arguments == null || Arguments [0] == null)
 678                                 return "";
 679
 680                         ArrayList pos_args = (ArrayList) Arguments [0];
 681                         if (pos_args.Count == 0)
 682                                 return "";
 683                         else if (pos_args.Count > 2){
 684                                 Error_AttributeConstructorMismatch ();
 685                                 return null;
 686                         }
 687
 688                         Argument arg = (Argument) pos_args [0];
 689                         if (!(arg.Expr is StringConstant)){
 690                                 Error_AttributeConstructorMismatch ();
 691                                 return null;
 692                         }
 693
 694                         if (pos_args.Count == 2){
 695                                 Argument arg2 = (Argument) pos_args [1];
 696                                 if (!(arg2.Expr is BoolConstant)){
 697                                         Error_AttributeConstructorMismatch ();
 698                                         return null;
 699                                 }
 700                                 is_error = ((BoolConstant) arg2.Expr).Value;
 701                         }
 702
 703                         return ((StringConstant) arg.Expr).Value;
 704                 }
 705
 706                 public string IndexerName_GetIndexerName (EmitContext ec)
 707                 {
 708                         if (Arguments == null || Arguments [0] == null){
 709                                 Error_AttributeConstructorMismatch ();
 710                                 return null;
 711                         }
 712                         ArrayList pos_args = (ArrayList) Arguments [0];
 713                         if (pos_args.Count != 1) {
 714                                 Error_AttributeConstructorMismatch ();
 715                                 return null;
 716                         }
 717
 718                         Argument arg = (Argument) pos_args [0];
 719                         if (!arg.Resolve (ec, Location))
 720                                 return null;
 721
 722                         StringConstant sc = arg.Expr as StringConstant;
 723                         if (sc == null){
 724                                 Error_AttributeConstructorMismatch ();
 725                                 return null;
 726                         }
 727
 728                         return sc.Value;
 729                 }
 730
 731                 /// <summary>
 732                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 733                 /// before ApplyAttribute. We need to resolve the arguments.
 734                 /// This situation occurs when class deps is differs from Emit order.
 735                 /// </summary>
 736                 public bool GetClsCompliantAttributeValue (DeclSpace ds)
 737                 {
 738                         if (pos_values == null) {
 739                                 EmitContext ec = new EmitContext (ds, ds, Location, null, null, 0, false);
 740
 741                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 742                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 743                                 Resolve (ec);
 744                         }
 745
 746                         // Some error occurred
 747                         if (pos_values [0] == null)
 748                                 return false;
 749
 750                         return (bool)pos_values [0];
 751                 }
 752
 753                 public object GetPositionalValue (int i)
 754                 {
 755                         return (pos_values == null) ? null : pos_values[i];
 756                 }
 757
 758                 object GetFieldValue (string name)
 759                 {
 760                         int i;
 761                         if (field_info_arr == null)
 762                                 return null;
 763                         i = 0;
 764                         foreach (FieldInfo fi in field_info_arr) {
 765                                 if (fi.Name == name)
 766                                         return field_values_arr [i];
 767                                 i++;
 768                         }
 769                         return null;
 770                 }
 771
 772                 public UnmanagedMarshal GetMarshal ()
 773                 {
 774                         object o = GetFieldValue ("ArraySubType");
 775                         UnmanagedType array_sub_type = o == null ? UnmanagedType.I4 : (UnmanagedType) o;
 776
 777                         switch (UnmanagedType) {
 778                         case UnmanagedType.CustomMarshaler:
 779                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
 780                                                                        BindingFlags.Static | BindingFlags.Public);
 781                                 if (define_custom == null)
 782                                         return null;
 783
 784                                 object [] args = new object [4];
 785                                 args [0] = GetFieldValue ("MarshalTypeRef");
 786                                 args [1] = GetFieldValue ("MarshalCookie");
 787                                 args [2] = GetFieldValue ("MarshalType");
 788                                 args [3] = Guid.Empty;
 789                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
 790
 791                         case UnmanagedType.LPArray:
 792                                 return UnmanagedMarshal.DefineLPArray (array_sub_type);
 793
 794                         case UnmanagedType.SafeArray:
 795                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
 796
 797                         case UnmanagedType.ByValArray:
 798                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
 799
 800                         case UnmanagedType.ByValTStr:
 801                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
 802
 803                         default:
 804                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
 805                         }
 806                 }
 807
 808                 public bool IsInternalCall
 809                 {
 810                         get { return ImplOptions == MethodImplOptions.InternalCall; }
 811                 }
 812
 813                 protected virtual bool CanIgnoreInvalidAttribute (Attributable ias)
 814                 {
 815                         return false;
 816                 }
 817
 818                 /// <summary>
 819                 /// Emit attribute for Attributable symbol
 820                 /// </summary>
 821                 public void Emit (EmitContext ec, Attributable ias, ListDictionary emitted_attr)
 822                 {
 823                         CustomAttributeBuilder cb = Resolve (ec);
 824                         if (cb == null)
 825                                 return;
 826
 827                         AttributeUsageAttribute usage_attr = GetAttributeUsage ();
 828                         if ((usage_attr.ValidOn & ias.AttributeTargets) == 0) {
 829                                 // The parser applies toplevel attributes both to the assembly and
 830                                 // to a top-level class, if any.  So, be silent about them.
 831                                 if (! CanIgnoreInvalidAttribute (ias))
 832                                         Error_AttributeNotValidForElement (this, Location);
 833                                 return;
 834                         }
 835
 836                         ias.ApplyAttributeBuilder (this, cb);
 837
 838                         // Because default target is null (we save some space). We need to transform it here
 839                         // for distinction between "default" and "doesn't exist"
 840                         string target = Target == null ? "default" : Target;
 841                         string emitted = emitted_attr [Type] as string;
 842                         if (emitted == target && !usage_attr.AllowMultiple) {
 843                                 Report.Error (579, Location, "Duplicate '" + Name + "' attribute");
 844                         }
 845
 846                         emitted_attr [Type] = target;
 847
 848                         // Here we are testing attribute arguments for array usage (error 3016)
 849                         if (ias.IsClsCompliaceRequired (ec.DeclSpace)) {
 850                                 if (Arguments == null)
 851                                         return;
 852
 853                                 ArrayList pos_args = (ArrayList) Arguments [0];
 854                                 if (pos_args != null) {
 855                                         foreach (Argument arg in pos_args) {
 856                                                 // Type is undefined (was error 246)
 857                                                 if (arg.Type == null)
 858                                                         return;
 859
 860                                                 if (arg.Type.IsArray) {
 861                                                         Report.Error_T (3016, Location);
 862                                                         return;
 863                                                 }
 864                                         }
 865                                 }
 866
 867                                 if (Arguments.Count < 2)
 868                                         return;
 869
 870                                 ArrayList named_args = (ArrayList) Arguments [1];
 871                                 foreach (DictionaryEntry de in named_args) {
 872                                         Argument arg  = (Argument) de.Value;
 873
 874                                         // Type is undefined (was error 246)
 875                                         if (arg.Type == null)
 876                                                 return;
 877
 878                                         if (arg.Type.IsArray) {
 879                                                 Report.Error_T (3016, Location);
 880                                                 return;
 881                                         }
 882                                 }
 883                         }
 884                 }
 885
 886                 public object GetValue (EmitContext ec, Constant c, Type target)
 887                 {
 888                         if (Convert.ImplicitConversionExists (ec, c, target))
 889                                 return c.GetValue ();
 890
 891                         Convert.Error_CannotImplicitConversion (Location, c.Type, target);
 892                         return null;
 893                 }
 894
 895                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,
 896                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
 897                 {
 898                         //
 899                         // We extract from the attribute the information we need
 900                         //
 901
 902                         if (Arguments == null) {
 903                                 Console.WriteLine ("Internal error : this is not supposed to happen !");
 904                                 return null;
 905                         }
 906
 907                         ResolveType (ec, true);
 908                         if (Type == null)
 909                                 return null;
 910
 911                         ArrayList named_args = new ArrayList ();
 912
 913                         ArrayList pos_args = (ArrayList) Arguments [0];
 914                         if (Arguments.Count > 1)
 915                                 named_args = (ArrayList) Arguments [1];
 916
 917
 918                         string dll_name = null;
 919
 920                         Argument tmp = (Argument) pos_args [0];
 921
 922                         if (!tmp.Resolve (ec, Location))
 923                                 return null;
 924
 925                         if (tmp.Expr is Constant)
 926                                 dll_name = (string) ((Constant) tmp.Expr).GetValue ();
 927                         else {
 928                                 Error_AttributeArgumentNotValid (Location);
 929                                 return null;
 930                         }
 931
 932                         // Now we process the named arguments
 933                         CallingConvention cc = CallingConvention.Winapi;
 934                         CharSet charset = CharSet.Ansi;
 935                         bool preserve_sig = true;
 936 #if FIXME
 937                         bool exact_spelling = false;
 938 #endif
 939                         bool set_last_err = false;
 940                         string entry_point = null;
 941
 942                         for (int i = 0; i < named_args.Count; i++) {
 943
 944                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 945
 946                                 string member_name = (string) de.Key;
 947                                 Argument a  = (Argument) de.Value;
 948
 949                                 if (!a.Resolve (ec, Location))
 950                                         return null;
 951
 952                                 Expression member = Expression.MemberLookup (
 953                                         ec, Type, member_name,
 954                                         MemberTypes.Field | MemberTypes.Property,
 955                                         BindingFlags.Public | BindingFlags.Instance,
 956                                         Location);
 957
 958                                 if (member == null || !(member is FieldExpr)) {
 959                                         Error_InvalidNamedArgument (member_name);
 960                                         return null;
 961                                 }
 962
 963                                 if (member is FieldExpr) {
 964                                         FieldExpr fe = (FieldExpr) member;
 965                                         FieldInfo fi = fe.FieldInfo;
 966
 967                                         if (fi.IsInitOnly) {
 968                                                 Error_InvalidNamedArgument (member_name);
 969                                                 return null;
 970                                         }
 971
 972                                         if (a.Expr is Constant) {
 973                                                 Constant c = (Constant) a.Expr;
 974
 975                                                 try {
 976                                                         if (member_name == "CallingConvention"){
 977                                                                 object val = GetValue (ec, c, typeof (CallingConvention));
 978                                                                 if (val == null)
 979                                                                         return null;
 980                                                                 cc = (CallingConvention) val;
 981                                                         } else if (member_name == "CharSet"){
 982                                                                 charset = (CharSet) c.GetValue ();
 983                                                         } else if (member_name == "EntryPoint")
 984                                                                 entry_point = (string) c.GetValue ();
 985                                                         else if (member_name == "SetLastError")
 986                                                                 set_last_err = (bool) c.GetValue ();
 987 #if FIXME
 988                                                         else if (member_name == "ExactSpelling")
 989                                                                 exact_spelling = (bool) c.GetValue ();
 990 #endif
 991                                                         else if (member_name == "PreserveSig")
 992                                                                 preserve_sig = (bool) c.GetValue ();
 993                                                 } catch (InvalidCastException){
 994                                                         Error_InvalidNamedArgument (member_name);
 995                                                         Error_AttributeArgumentNotValid (Location);
 996                                                 }
 997                                         } else {
 998                                                 Error_AttributeArgumentNotValid (Location);
 999                                                 return null;
1000                                         }
1001
1002                                 }
1003                         }
1004
1005                         if (entry_point == null)
1006                                 entry_point = name;
1007                         if (set_last_err)
1008                                 charset = (CharSet)((int)charset | 0x40);
1009
1010                         MethodBuilder mb = builder.DefinePInvokeMethod (
1011                                 name, dll_name, entry_point, flags | MethodAttributes.HideBySig,
1012                                 CallingConventions.Standard,
1013                                 ret_type,
1014                                 param_types,
1015                                 cc,
1016                                 charset);
1017
1018                         if (preserve_sig)
1019                                 mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1020
1021                         return mb;
1022                 }
1023
1024                 private Expression GetValue ()
1025                 {
1026                         if ((Arguments == null) || (Arguments.Count < 1))
1027                                 return null;
1028                         ArrayList al = (ArrayList) Arguments [0];
1029                         if ((al == null) || (al.Count < 1))
1030                                 return null;
1031                         Argument arg = (Argument) al [0];
1032                         if ((arg == null) || (arg.Expr == null))
1033                                 return null;
1034                         return arg.Expr;
1035                 }
1036
1037                 public string GetString ()
1038                 {
1039                         Expression e = GetValue ();
1040                         if (e is StringLiteral)
1041                                 return (e as StringLiteral).Value;
1042                         return null;
1043                 }
1044
1045                 public bool GetBoolean ()
1046                 {
1047                         Expression e = GetValue ();
1048                         if (e is BoolLiteral)
1049                                 return (e as BoolLiteral).Value;
1050                         return false;
1051                 }
1052         }
1053
1054
1055         /// <summary>
1056         /// For global attributes (assembly, module) we need special handling.
1057         /// Attributes can be located in the several files
1058         /// </summary>
1059         public class GlobalAttribute: Attribute
1060         {
1061                 public readonly NamespaceEntry ns;
1062
1063                 public GlobalAttribute (TypeContainer container, string target, string name, ArrayList args, Location loc):
1064                         base (target, name, args, loc)
1065                 {
1066                         ns = container.NamespaceEntry;
1067                 }
1068
1069                 protected override Type CheckAttributeType (EmitContext ec, bool complain)
1070                 {
1071                         NamespaceEntry old = ec.DeclSpace.NamespaceEntry;
1072                         if (old == null || old.NS == null || old.NS == Namespace.Root)
1073                                 ec.DeclSpace.NamespaceEntry = ns;
1074                         return base.CheckAttributeType (ec, complain);
1075                 }
1076
1077                 protected override bool CanIgnoreInvalidAttribute (Attributable ias)
1078                 {
1079                         // Ignore error if this attribute is shared between the Assembly
1080                         // and a top-level class.  The parser couldn't figure out which entity
1081                         // this attribute belongs to.  If this attribute is erroneous, it should
1082                         // be caught when it is processed by the top-level class.
1083
1084                         return (Target == null && ias is CommonAssemblyModulClass);
1085                 }
1086         }
1087
1088         public class Attributes {
1089                 public ArrayList Attrs;
1090
1091                 public Attributes (Attribute a)
1092                 {
1093                         Attrs = new ArrayList ();
1094                         Attrs.Add (a);
1095                 }
1096
1097                 public Attributes (ArrayList attrs)
1098                 {
1099                         Attrs = attrs;
1100                 }
1101
1102                 public void AddAttributes (ArrayList attrs)
1103                 {
1104                         Attrs.AddRange (attrs);
1105                 }
1106
1107                 /// <summary>
1108                 /// Checks whether attribute target is valid for the current element
1109                 /// </summary>
1110                 public void CheckTargets (string[] possible_targets)
1111                 {
1112                         foreach (Attribute a in Attrs) {
1113                                 if (a.Target == null)
1114                                         continue;
1115
1116                                 if (((IList) possible_targets).Contains (a.Target))
1117                                         continue;
1118
1119                                 StringBuilder sb = new StringBuilder ();
1120                                 foreach (string s in possible_targets) {
1121                                         sb.Append (s);
1122                                         sb.Append (", ");
1123                                 }
1124                                 sb.Remove (sb.Length - 2, 2);
1125                                 Report.Error_T (657, a.Location, a.Target, sb.ToString ());
1126                         }
1127                 }
1128
1129                 private Attribute Search (Type t, EmitContext ec, bool complain)
1130                 {
1131                         foreach (Attribute a in Attrs) {
1132                                 if (a.ResolveType (ec, false) == t)
1133                                         return a;
1134                         }
1135                         return null;
1136                 }
1137
1138                 public Attribute Search (Type t, EmitContext ec)
1139                 {
1140                         return Search (t, ec, true);
1141                 }
1142
1143                 public void Emit (EmitContext ec, Attributable ias)
1144                 {
1145                         ListDictionary ld = new ListDictionary ();
1146
1147                         foreach (Attribute a in Attrs)
1148                                 a.Emit (ec, ias, ld);
1149                 }
1150
1151                 public bool Contains (Type t, EmitContext ec)
1152                 {
1153                         return Search (t, ec) != null;
1154                 }
1155
1156                 public Attribute GetClsCompliantAttribute (EmitContext ec)
1157                 {
1158                         return Search (TypeManager.cls_compliant_attribute_type, ec, false);
1159                 }
1160
1161                 /// <summary>
1162                 /// Pulls the IndexerName attribute from an Indexer if it exists.
1163                 /// </summary>
1164                 public string ScanForIndexerName (EmitContext ec)
1165                 {
1166                         Attribute a = Search (TypeManager.indexer_name_type, ec);
1167                         if (a == null)
1168                                 return null;
1169
1170                         // Remove the attribute from the list
1171                         //TODO: It is very close to hack and it can crash here
1172                         Attrs.Remove (a);
1173
1174                         return a.IndexerName_GetIndexerName (ec);
1175                 }
1176
1177         }
1178
1179         /// <summary>
1180         /// Helper class for attribute verification routine.
1181         /// </summary>
1182         sealed class AttributeTester
1183         {
1184                 static PtrHashtable analyzed_types = new PtrHashtable ();
1185
1186                 private AttributeTester ()
1187                 {
1188                 }
1189
1190                 /// <summary>
1191                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1192                 /// It tests differing only in ref or out, or in array rank.
1193                 /// </summary>
1194                 public static bool AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1195                 {
1196                         if (types_a == null || types_b == null)
1197                                 return true;
1198
1199                         if (types_a.Length != types_b.Length)
1200                                 return true;
1201
1202                         for (int i = 0; i < types_b.Length; ++i) {
1203                                 Type aType = types_a [i];
1204                                 Type bType = types_b [i];
1205
1206                                 if (aType.IsArray && bType.IsArray && aType.GetArrayRank () != bType.GetArrayRank () && aType.GetElementType () == bType.GetElementType ()) {
1207                                         return false;
1208                                 }
1209
1210                                 Type aBaseType = aType;
1211                                 bool is_either_ref_or_out = false;
1212
1213                                 if (aType.IsByRef || aType.IsPointer) {
1214                                         aBaseType = aType.GetElementType ();
1215                                         is_either_ref_or_out = true;
1216                                 }
1217
1218                                 Type bBaseType = bType;
1219                                 if (bType.IsByRef || bType.IsPointer)
1220                                 {
1221                                         bBaseType = bType.GetElementType ();
1222                                         is_either_ref_or_out = !is_either_ref_or_out;
1223                                 }
1224
1225                                 if (aBaseType != bBaseType)
1226                                         continue;
1227
1228                                 if (is_either_ref_or_out)
1229                                         return false;
1230                         }
1231                         return true;
1232                 }
1233
1234                 /// <summary>
1235                 /// Goes through all parameters and test if they are CLS-Compliant.
1236                 /// </summary>
1237                 public static bool AreParametersCompliant (Parameter[] fixedParameters, Location loc)
1238                 {
1239                         if (fixedParameters == null)
1240                                 return true;
1241
1242                         foreach (Parameter arg in fixedParameters) {
1243                                 if (!AttributeTester.IsClsCompliant (arg.ParameterType)) {
1244                                         Report.Error_T (3001, loc, arg.GetSignatureForError ());
1245                                         return false;
1246                                 }
1247                         }
1248                         return true;
1249                 }
1250
1251
1252                 /// <summary>
1253                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1254                 /// </summary>
1255                 public static bool IsClsCompliant (Type type)
1256                 {
1257                         if (type == null)
1258                                 return true;
1259
1260                         object type_compliance = analyzed_types[type];
1261                         if (type_compliance != null)
1262                                 return type_compliance == TRUE;
1263
1264                         if (type.IsPointer) {
1265                                 analyzed_types.Add (type, null);
1266                                 return false;
1267                         }
1268
1269                         bool result;
1270                         if (type.IsArray || type.IsByRef)       {
1271                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1272                         } else {
1273                                 result = AnalyzeTypeCompliance (type);
1274                         }
1275                         analyzed_types.Add (type, result ? TRUE : FALSE);
1276                         return result;
1277                 }
1278
1279                 static object TRUE = new object ();
1280                 static object FALSE = new object ();
1281
1282                 /// <summary>
1283                 /// Non-hierarchical CLS Compliance analyzer
1284                 /// </summary>
1285                 public static bool IsComplianceRequired (MemberInfo mi, DeclSpace ds)
1286                 {
1287                         DeclSpace temp_ds = TypeManager.LookupDeclSpace (mi.DeclaringType);
1288
1289                         // Type is external, we can get attribute directly
1290                         if (temp_ds == null) {
1291                                 object[] cls_attribute = mi.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1292                                 return (cls_attribute.Length == 1 && ((CLSCompliantAttribute)cls_attribute[0]).IsCompliant);
1293                         }
1294
1295                         string tmp_name;
1296                         // Interface doesn't store full name
1297                         if (temp_ds is Interface)
1298                                 tmp_name = mi.Name;
1299                         else
1300                                 tmp_name = String.Concat (temp_ds.Name, ".", mi.Name);
1301
1302                         MemberCore mc = temp_ds.GetDefinition (tmp_name) as MemberCore;
1303                         return mc.IsClsCompliaceRequired (ds);
1304                 }
1305
1306                 public static void VerifyModulesClsCompliance ()
1307                 {
1308                         Module[] modules = TypeManager.Modules;
1309                         if (modules == null)
1310                                 return;
1311
1312                         // The first module is generated assembly
1313                         for (int i = 1; i < modules.Length; ++i) {
1314                                 Module module = modules [i];
1315                                 if (!IsClsCompliant (module)) {
1316                                         Report.Error_T (3013, module.Name);
1317                                         return;
1318                                 }
1319                         }
1320                 }
1321
1322                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1323                 {
1324                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1325                         if (CompliantAttribute.Length == 0)
1326                                 return false;
1327
1328                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1329                 }
1330
1331                 static bool AnalyzeTypeCompliance (Type type)
1332                 {
1333                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1334                         if (ds != null) {
1335                                 return ds.IsClsCompliaceRequired (ds.Parent);
1336                         }
1337
1338                         if (type.IsGenericParameter)
1339                                 return false;
1340
1341                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1342                         if (CompliantAttribute.Length == 0)
1343                                 return IsClsCompliant (type.Assembly);
1344
1345                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1346                 }
1347         }
1348 }