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