mcs/mcs/attribute.cs

   1 //
   2 // attribute.cs: Attribute Handler
   3 //
   4 // Author: Ravi Pratap (ravi@ximian.com)
   5 //         Marek Safar (marek.safar@seznam.cz)
   6 //
   7 // Licensed under the terms of the GNU GPL
   8 //
   9 // (C) 2001 Ximian, Inc (http://www.ximian.com)
  10 //
  11 //
  12
  13 using System;
  14 using System.Diagnostics;
  15 using System.Collections;
  16 using System.Collections.Specialized;
  17 using System.Reflection;
  18 using System.Reflection.Emit;
  19 using System.Runtime.InteropServices;
  20 using System.Runtime.CompilerServices;
  21 using System.Security;
  22 using System.Security.Permissions;
  23 using System.Text;
  24 using System.IO;
  25
  26 namespace Mono.CSharp {
  27
  28         /// <summary>
  29         ///   Base class for objects that can have Attributes applied to them.
  30         /// </summary>
  31         public abstract class Attributable {
  32                 /// <summary>
  33                 ///   Attributes for this type
  34                 /// </summary>
  35                 Attributes attributes;
  36
  37                 public Attributable (Attributes attrs)
  38                 {
  39                         attributes = attrs;
  40                 }
  41
  42                 public Attributes OptAttributes
  43                 {
  44                         get {
  45                                 return attributes;
  46                         }
  47                         set {
  48                                 attributes = value;
  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 one AttributeTarget for this element.
  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                 public abstract string[] ValidAttributeTargets { get; }
  69         };
  70
  71         public class Attribute {
  72                 public readonly string ExplicitTarget;
  73                 public AttributeTargets Target;
  74
  75                 // TODO: remove this member
  76                 public readonly string    Name;
  77                 public readonly Expression LeftExpr;
  78                 public readonly string Identifier;
  79
  80                 public readonly ArrayList Arguments;
  81
  82                 public readonly Location Location;
  83
  84                 public Type Type;
  85
  86                 bool resolve_error;
  87
  88                 static AttributeUsageAttribute DefaultUsageAttribute = new AttributeUsageAttribute (AttributeTargets.All);
  89                 static Assembly orig_sec_assembly;
  90
  91                 // non-null if named args present after Resolve () is called
  92                 PropertyInfo [] prop_info_arr;
  93                 FieldInfo [] field_info_arr;
  94                 object [] field_values_arr;
  95                 object [] prop_values_arr;
  96                 object [] pos_values;
  97
  98                 static PtrHashtable usage_attr_cache = new PtrHashtable ();
  99
 100                 public Attribute (string target, Expression left_expr, string identifier, ArrayList args, Location loc)
 101                 {
 102                         LeftExpr = left_expr;
 103                         Identifier = identifier;
 104                         Name = LeftExpr == null ? identifier : LeftExpr + "." + identifier;
 105                         Arguments = args;
 106                         Location = loc;
 107                         ExplicitTarget = target;
 108                 }
 109
 110                 void Error_InvalidNamedArgument (string name)
 111                 {
 112                         Report.Error (617, Location, "`{0}' is not a valid named attribute argument. Named attribute arguments must be fields which are not readonly, static, const or read-write properties which are public and not static",
 113                               name);
 114                 }
 115
 116                 void Error_InvalidNamedAgrumentType (string name)
 117                 {
 118                         Report.Error (655, Location, "`{0}' is not a valid named attribute argument because it is not a valid attribute parameter type", name);
 119                 }
 120
 121                 static void Error_AttributeArgumentNotValid (string extra, Location loc)
 122                 {
 123                         Report.Error (182, loc,
 124                                       "An attribute argument must be a constant expression, typeof " +
 125                                       "expression or array creation expression" + extra);
 126                 }
 127
 128                 static void Error_AttributeArgumentNotValid (Location loc)
 129                 {
 130                         Error_AttributeArgumentNotValid ("", loc);
 131                 }
 132
 133
 134                 /// <summary>
 135                 /// This is rather hack. We report many emit attribute error with same error to be compatible with
 136                 /// csc. But because csc has to report them this way because error came from ilasm we needn't.
 137                 /// </summary>
 138                 public void Error_AttributeEmitError (string inner)
 139                 {
 140                         Report.Error (647, Location, "Error during emitting `{0}' attribute. The reason is `{1}'", TypeManager.CSharpName (Type), inner);
 141                 }
 142
 143                 public void Error_InvalidSecurityParent ()
 144                 {
 145                         Error_AttributeEmitError ("it is attached to invalid parent");
 146                 }
 147
 148                 protected virtual FullNamedExpression ResolveAsTypeTerminal (Expression expr, EmitContext ec, bool silent)
 149                 {
 150                         return expr.ResolveAsTypeTerminal (ec, silent);
 151                 }
 152
 153                 protected virtual FullNamedExpression ResolveAsTypeStep (Expression expr, EmitContext ec, bool silent)
 154                 {
 155                         return expr.ResolveAsTypeStep (ec, silent);
 156                 }
 157
 158                 Type ResolvePossibleAttributeType (EmitContext ec, string name, bool silent, ref bool is_attr)
 159                 {
 160                         FullNamedExpression fn;
 161                         if (LeftExpr == null) {
 162                                 fn = ResolveAsTypeTerminal (new SimpleName (name, Location), ec, silent);
 163                         } else {
 164                                 fn = ResolveAsTypeStep (LeftExpr, ec, silent);
 165                                 if (fn == null)
 166                                         return null;
 167                                 fn = new MemberAccess (fn, name, Location).ResolveAsTypeTerminal (ec, silent);
 168                         }
 169
 170                         TypeExpr te = fn as TypeExpr;
 171                         if (te == null)
 172                                 return null;
 173
 174                         Type t = te.Type;
 175                         if (t.IsSubclassOf (TypeManager.attribute_type)) {
 176                                 is_attr = true;
 177                         } else if (!silent) {
 178                                 Report.SymbolRelatedToPreviousError (t);
 179                                 Report.Error (616, Location, "`{0}': is not an attribute class", TypeManager.CSharpName (t));
 180                         }
 181                         return t;
 182                 }
 183
 184                 /// <summary>
 185                 ///   Tries to resolve the type of the attribute. Flags an error if it can't, and complain is true.
 186                 /// </summary>
 187                 void ResolveAttributeType (EmitContext ec)
 188                 {
 189                         bool t1_is_attr = false;
 190                         Type t1 = ResolvePossibleAttributeType (ec, Identifier, true, ref t1_is_attr);
 191
 192                         // FIXME: Shouldn't do this for quoted attributes: [@A]
 193                         bool t2_is_attr = false;
 194                         Type t2 = ResolvePossibleAttributeType (ec, Identifier + "Attribute", true, ref t2_is_attr);
 195
 196                         if (t1_is_attr && t2_is_attr) {
 197                                 Report.Error (1614, Location, "`{0}' is ambiguous between `{0}' and `{0}Attribute'. Use either `@{0}' or `{0}Attribute'", GetSignatureForError ());
 198                                 resolve_error = true;
 199                                 return;
 200                         }
 201
 202                         if (t1_is_attr) {
 203                                 Type = t1;
 204                                 return;
 205                         }
 206
 207                         if (t2_is_attr) {
 208                                 Type = t2;
 209                                 return;
 210                         }
 211
 212                         if (t1 == null && t2 == null)
 213                                 ResolvePossibleAttributeType (ec, Identifier, false, ref t1_is_attr);
 214                         if (t1 != null)
 215                                 ResolvePossibleAttributeType (ec, Identifier, false, ref t1_is_attr);
 216                         if (t2 != null)
 217                                 ResolvePossibleAttributeType (ec, Identifier + "Attribute", false, ref t2_is_attr);
 218
 219                         resolve_error = true;
 220                 }
 221
 222                 public virtual Type ResolveType (EmitContext ec)
 223                 {
 224                         if (Type == null && !resolve_error)
 225                                 ResolveAttributeType (ec);
 226                         return Type;
 227                 }
 228
 229                 public string GetSignatureForError ()
 230                 {
 231                         return LeftExpr == null ? Identifier : LeftExpr.GetSignatureForError () + "." + Identifier;
 232                 }
 233
 234                 //
 235                 // Given an expression, if the expression is a valid attribute-argument-expression
 236                 // returns an object that can be used to encode it, or null on failure.
 237                 //
 238                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, Type arg_type, out object result)
 239                 {
 240                         if (e is EnumConstant) {
 241                                 if (RootContext.StdLib)
 242                                         result = ((EnumConstant)e).GetValueAsEnumType ();
 243                                 else
 244                                         result = ((EnumConstant)e).GetValue ();
 245
 246                                 return true;
 247                         }
 248
 249                         Constant constant = e as Constant;
 250                         if (constant != null) {
 251                                 if (e.Type != arg_type) {
 252                                         constant = Const.ChangeType (loc, constant, arg_type);
 253                                         if (constant == null) {
 254                                                 result = null;
 255                                                 Error_AttributeArgumentNotValid (loc);
 256                                                 return false;
 257                                         }
 258                                 }
 259                                 result = constant.GetValue ();
 260                                 return true;
 261                         } else if (e is TypeOf) {
 262                                 result = ((TypeOf) e).TypeArg;
 263                                 return true;
 264                         } else if (e is ArrayCreation){
 265                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();
 266                                 if (result != null)
 267                                         return true;
 268                         } else if (e is EmptyCast) {
 269                                 Expression child = ((EmptyCast)e).Child;
 270                                 return GetAttributeArgumentExpression (child, loc, child.Type, out result);
 271                         }
 272
 273                         result = null;
 274                         Error_AttributeArgumentNotValid (loc);
 275                         return false;
 276                 }
 277
 278                 bool IsValidArgumentType (Type t)
 279                 {
 280                         return TypeManager.IsPrimitiveType (t) ||
 281                                 (t.IsArray && TypeManager.IsPrimitiveType (t.GetElementType ())) ||
 282                                 TypeManager.IsEnumType (t) ||
 283                                 t == TypeManager.string_type ||
 284                                 t == TypeManager.object_type ||
 285                                 t == TypeManager.type_type;
 286                 }
 287
 288                 // Cache for parameter-less attributes
 289                 static PtrHashtable att_cache = new PtrHashtable ();
 290
 291                 public CustomAttributeBuilder Resolve (EmitContext ec)
 292                 {
 293                         if (resolve_error)
 294                                 return null;
 295
 296                         resolve_error = true;
 297
 298                         if (Type == null) {
 299                                 ResolveAttributeType (ec);
 300                                 if (Type == null)
 301                                         return null;
 302                         }
 303
 304                         if (Type.IsAbstract) {
 305                                 Report.Error (653, Location, "Cannot apply attribute class `{0}' because it is abstract", GetSignatureForError ());
 306                                 return null;
 307                         }
 308
 309                         if (Arguments == null) {
 310                                 object o = att_cache [Type];
 311                                 if (o != null) {
 312                                         resolve_error = false;
 313                                         return (CustomAttributeBuilder)o;
 314                                 }
 315                         }
 316
 317                         ConstructorInfo ctor = ResolveArguments (ec);
 318                         if (ctor == null)
 319                                 return null;
 320
 321                         CustomAttributeBuilder cb;
 322
 323                         try {
 324                                 if (prop_info_arr != null || field_info_arr != null) {
 325                                         cb = new CustomAttributeBuilder (
 326                                                 ctor, pos_values,
 327                                                 prop_info_arr, prop_values_arr,
 328                                                 field_info_arr, field_values_arr);
 329                                 } else {
 330                                         cb = new CustomAttributeBuilder (
 331                                                 ctor, pos_values);
 332
 333                                         if (pos_values.Length == 0)
 334                                                 att_cache.Add (Type, cb);
 335                                 }
 336                         }
 337                         catch (Exception) {
 338                                 Error_AttributeArgumentNotValid (Location);
 339                                 return null;
 340                         }
 341
 342                         resolve_error = false;
 343                         return cb;
 344                 }
 345
 346                 protected virtual ConstructorInfo ResolveArguments (EmitContext ec)
 347                 {
 348                         // Now we extract the positional and named arguments
 349
 350                         ArrayList pos_args = null;
 351                         ArrayList named_args = null;
 352                         int pos_arg_count = 0;
 353                         int named_arg_count = 0;
 354
 355                         if (Arguments != null) {
 356                                 pos_args = (ArrayList) Arguments [0];
 357                                 if (pos_args != null)
 358                                         pos_arg_count = pos_args.Count;
 359                                 if (Arguments.Count > 1) {
 360                                         named_args = (ArrayList) Arguments [1];
 361                                         named_arg_count = named_args.Count;
 362                                 }
 363                         }
 364
 365                         pos_values = new object [pos_arg_count];
 366
 367                         //
 368                         // First process positional arguments
 369                         //
 370
 371                         int i;
 372                         for (i = 0; i < pos_arg_count; i++) {
 373                                 Argument a = (Argument) pos_args [i];
 374                                 Expression e;
 375
 376                                 if (!a.Resolve (ec, Location))
 377                                         return null;
 378
 379                                 e = a.Expr;
 380
 381                                 object val;
 382                                 if (!GetAttributeArgumentExpression (e, Location, a.Type, out val))
 383                                         return null;
 384
 385                                 pos_values [i] = val;
 386
 387                                 if (i == 0 && Type == TypeManager.attribute_usage_type && (int)val == 0) {
 388                                         Report.Error (591, Location, "Invalid value for argument to 'System.AttributeUsage' attribute");
 389                                         return null;
 390                                 }
 391                         }
 392
 393                         //
 394                         // Now process named arguments
 395                         //
 396
 397                         ArrayList field_infos = null;
 398                         ArrayList prop_infos  = null;
 399                         ArrayList field_values = null;
 400                         ArrayList prop_values = null;
 401                         Hashtable seen_names = null;
 402
 403                         if (named_arg_count > 0) {
 404                                 field_infos = new ArrayList ();
 405                                 prop_infos  = new ArrayList ();
 406                                 field_values = new ArrayList ();
 407                                 prop_values = new ArrayList ();
 408
 409                                 seen_names = new Hashtable();
 410                         }
 411
 412                         for (i = 0; i < named_arg_count; i++) {
 413                                 DictionaryEntry de = (DictionaryEntry) named_args [i];
 414                                 string member_name = (string) de.Key;
 415                                 Argument a  = (Argument) de.Value;
 416                                 Expression e;
 417
 418                                 if (seen_names.Contains(member_name)) {
 419                                         Report.Error(643, Location, "'" + member_name + "' duplicate named attribute argument");
 420                                         return null;
 421                                 }
 422                                 seen_names.Add(member_name, 1);
 423
 424                                 if (!a.Resolve (ec, Location))
 425                                         return null;
 426
 427                                 Expression member = Expression.MemberLookup (
 428                                         ec, Type, member_name,
 429                                         MemberTypes.Field | MemberTypes.Property,
 430                                         BindingFlags.Public | BindingFlags.Instance,
 431                                         Location);
 432
 433                                 if (member == null) {
 434                                         member = Expression.MemberLookup (ec, Type, member_name,
 435                                                 MemberTypes.Field | MemberTypes.Property, BindingFlags.NonPublic | BindingFlags.Instance,
 436                                                 Location);
 437
 438                                         if (member != null) {
 439                                                 Expression.ErrorIsInaccesible (Location, member.GetSignatureForError ());
 440                                                 return null;
 441                                         }
 442                                 }
 443
 444                                 if (member == null){
 445                                         Report.Error (117, Location, "`{0}' does not contain a definition for `{1}'",
 446                                                       Type, member_name);
 447                                         return null;
 448                                 }
 449
 450                                 if (!(member is PropertyExpr || member is FieldExpr)) {
 451                                         Error_InvalidNamedArgument (member_name);
 452                                         return null;
 453                                 }
 454
 455                                 e = a.Expr;
 456                                 if (member is PropertyExpr) {
 457                                         PropertyExpr pe = (PropertyExpr) member;
 458                                         PropertyInfo pi = pe.PropertyInfo;
 459
 460                                         if (!pi.CanWrite || !pi.CanRead) {
 461                                                 Report.SymbolRelatedToPreviousError (pi);
 462                                                 Error_InvalidNamedArgument (member_name);
 463                                                 return null;
 464                                         }
 465
 466                                         if (!IsValidArgumentType (pi.PropertyType)) {
 467                                                 Report.SymbolRelatedToPreviousError (pi);
 468                                                 Error_InvalidNamedAgrumentType (member_name);
 469                                                 return null;
 470                                         }
 471
 472                                         object value;
 473                                         if (!GetAttributeArgumentExpression (e, Location, pi.PropertyType, out value))
 474                                                 return null;
 475
 476                                         prop_values.Add (value);
 477                                         prop_infos.Add (pi);
 478
 479                                 } else if (member is FieldExpr) {
 480                                         FieldExpr fe = (FieldExpr) member;
 481                                         FieldInfo fi = fe.FieldInfo;
 482
 483                                         if (fi.IsInitOnly) {
 484                                                 Error_InvalidNamedArgument (member_name);
 485                                                 return null;
 486                                         }
 487
 488                                         if (!IsValidArgumentType (fi.FieldType)) {
 489                                                 Report.SymbolRelatedToPreviousError (fi);
 490                                                 Error_InvalidNamedAgrumentType (member_name);
 491                                                 return null;
 492                                         }
 493
 494                                         object value;
 495                                         if (!GetAttributeArgumentExpression (e, Location, fi.FieldType, out value))
 496                                                 return null;
 497
 498                                         field_values.Add (value);
 499                                         field_infos.Add (fi);
 500                                 }
 501                         }
 502
 503                         Expression mg = Expression.MemberLookup (
 504                                 ec, Type, ".ctor", MemberTypes.Constructor,
 505                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,
 506                                 Location);
 507
 508                         MethodBase constructor = Invocation.OverloadResolve (
 509                                 ec, (MethodGroupExpr) mg, pos_args, false, Location);
 510
 511                         if (constructor == null) {
 512                                 return null;
 513                         }
 514
 515
 516                         // Here we do the checks which should be done by corlib or by runtime.
 517                         // However Zoltan doesn't like it and every Mono compiler has to do it again.
 518
 519                         if (Type == TypeManager.guid_attr_type) {
 520                                 try {
 521                                         new Guid ((string)pos_values [0]);
 522                                 }
 523                                 catch (Exception e) {
 524                                         Error_AttributeEmitError (e.Message);
 525                                 }
 526                         }
 527 // TODO: reenable
 528 //                      if (Type == TypeManager.methodimpl_attr_type &&
 529 //                              pos_values.Length == 1 && ((Argument)pos_args [0]).Type == TypeManager.short_type &&
 530 //                              !System.Enum.IsDefined (TypeManager.method_impl_options, pos_values [0])) {
 531 //                                      Error_AttributeEmitError ("Incorrect argument value.");
 532 //                      }
 533
 534                         //
 535                         // Now we perform some checks on the positional args as they
 536                         // cannot be null for a constructor which expects a parameter
 537                         // of type object
 538                         //
 539
 540                         ParameterData pd = TypeManager.GetParameterData (constructor);
 541
 542                         int last_real_param = pd.Count;
 543                         if (pd.HasParams) {
 544                                 // When the params is not filled we need to put one
 545                                 if (last_real_param > pos_arg_count) {
 546                                         object [] new_pos_values = new object [pos_arg_count + 1];
 547                                         pos_values.CopyTo (new_pos_values, 0);
 548                                         new_pos_values [pos_arg_count] = new object [] {} ;
 549                                         pos_values = new_pos_values;
 550                                 }
 551                                 last_real_param--;
 552                         }
 553
 554                         for (int j = 0; j < pos_arg_count; ++j) {
 555                                 Argument a = (Argument) pos_args [j];
 556
 557                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {
 558                                         Error_AttributeArgumentNotValid (Location);
 559                                         return null;
 560                                 }
 561
 562                                 object value = pos_values [j];
 563                                 if (value != null && a.Type != value.GetType () && TypeManager.IsPrimitiveType (a.Type)) {
 564                                         bool fail;
 565                                         pos_values [j] = TypeManager.ChangeType (value, a.Type, out fail);
 566                                         if (fail) {
 567                                                 // TODO: Can failed ?
 568                                                 throw new NotImplementedException ();
 569                                         }
 570                                 }
 571
 572                                 if (j < last_real_param)
 573                                         continue;
 574
 575                                 if (j == last_real_param) {
 576                                         object [] array = new object [pos_arg_count - last_real_param];
 577                                         array [0] = pos_values [j];
 578                                         pos_values [j] = array;
 579                                         continue;
 580                                 }
 581
 582                                 object [] params_array = (object []) pos_values [last_real_param];
 583                                 params_array [j - last_real_param] = pos_values [j];
 584                         }
 585
 586                         // Adjust the size of the pos_values if it had params
 587                         if (last_real_param != pos_arg_count) {
 588                                 object [] new_pos_values = new object [last_real_param + 1];
 589                                 Array.Copy (pos_values, new_pos_values, last_real_param + 1);
 590                                 pos_values = new_pos_values;
 591                         }
 592
 593                         if (named_arg_count > 0) {
 594                                 prop_info_arr = new PropertyInfo [prop_infos.Count];
 595                                 field_info_arr = new FieldInfo [field_infos.Count];
 596                                 field_values_arr = new object [field_values.Count];
 597                                 prop_values_arr = new object [prop_values.Count];
 598
 599                                 field_infos.CopyTo  (field_info_arr, 0);
 600                                 field_values.CopyTo (field_values_arr, 0);
 601
 602                                 prop_values.CopyTo  (prop_values_arr, 0);
 603                                 prop_infos.CopyTo   (prop_info_arr, 0);
 604                         }
 605
 606                         return (ConstructorInfo) constructor;
 607                 }
 608
 609                 /// <summary>
 610                 ///   Get a string containing a list of valid targets for the attribute 'attr'
 611                 /// </summary>
 612                 public string GetValidTargets ()
 613                 {
 614                         StringBuilder sb = new StringBuilder ();
 615                         AttributeTargets targets = GetAttributeUsage (null).ValidOn;
 616
 617                         if ((targets & AttributeTargets.Assembly) != 0)
 618                                 sb.Append ("assembly, ");
 619
 620                         if ((targets & AttributeTargets.Module) != 0)
 621                                 sb.Append ("module, ");
 622
 623                         if ((targets & AttributeTargets.Class) != 0)
 624                                 sb.Append ("class, ");
 625
 626                         if ((targets & AttributeTargets.Struct) != 0)
 627                                 sb.Append ("struct, ");
 628
 629                         if ((targets & AttributeTargets.Enum) != 0)
 630                                 sb.Append ("enum, ");
 631
 632                         if ((targets & AttributeTargets.Constructor) != 0)
 633                                 sb.Append ("constructor, ");
 634
 635                         if ((targets & AttributeTargets.Method) != 0)
 636                                 sb.Append ("method, ");
 637
 638                         if ((targets & AttributeTargets.Property) != 0)
 639                                 sb.Append ("property, indexer, ");
 640
 641                         if ((targets & AttributeTargets.Field) != 0)
 642                                 sb.Append ("field, ");
 643
 644                         if ((targets & AttributeTargets.Event) != 0)
 645                                 sb.Append ("event, ");
 646
 647                         if ((targets & AttributeTargets.Interface) != 0)
 648                                 sb.Append ("interface, ");
 649
 650                         if ((targets & AttributeTargets.Parameter) != 0)
 651                                 sb.Append ("parameter, ");
 652
 653                         if ((targets & AttributeTargets.Delegate) != 0)
 654                                 sb.Append ("delegate, ");
 655
 656                         if ((targets & AttributeTargets.ReturnValue) != 0)
 657                                 sb.Append ("return, ");
 658
 659 #if NET_2_0
 660                         if ((targets & AttributeTargets.GenericParameter) != 0)
 661                                 sb.Append ("type parameter, ");
 662 #endif
 663                         return sb.Remove (sb.Length - 2, 2).ToString ();
 664                 }
 665
 666                 /// <summary>
 667                 /// Returns AttributeUsage attribute for this type
 668                 /// </summary>
 669                 AttributeUsageAttribute GetAttributeUsage (EmitContext ec)
 670                 {
 671                         AttributeUsageAttribute ua = usage_attr_cache [Type] as AttributeUsageAttribute;
 672                         if (ua != null)
 673                                 return ua;
 674
 675                         Class attr_class = TypeManager.LookupClass (Type);
 676
 677                         if (attr_class == null) {
 678                                 object[] usage_attr = Type.GetCustomAttributes (TypeManager.attribute_usage_type, true);
 679                                 ua = (AttributeUsageAttribute)usage_attr [0];
 680                                 usage_attr_cache.Add (Type, ua);
 681                                 return ua;
 682                         }
 683
 684                         Attribute a = attr_class.OptAttributes == null
 685                                 ? null
 686                                 : attr_class.OptAttributes.Search (TypeManager.attribute_usage_type, attr_class.EmitContext);
 687
 688                         ua = a == null
 689                                 ? DefaultUsageAttribute
 690                                 : a.GetAttributeUsageAttribute (attr_class.EmitContext);
 691
 692                         usage_attr_cache.Add (Type, ua);
 693                         return ua;
 694                 }
 695
 696                 AttributeUsageAttribute GetAttributeUsageAttribute (EmitContext ec)
 697                 {
 698                         if (pos_values == null)
 699                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 700                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 701                                 Resolve (ec);
 702
 703                         if (resolve_error)
 704                                 return DefaultUsageAttribute;
 705
 706                         AttributeUsageAttribute usage_attribute = new AttributeUsageAttribute ((AttributeTargets)pos_values [0]);
 707
 708                         object field = GetPropertyValue ("AllowMultiple");
 709                         if (field != null)
 710                                 usage_attribute.AllowMultiple = (bool)field;
 711
 712                         field = GetPropertyValue ("Inherited");
 713                         if (field != null)
 714                                 usage_attribute.Inherited = (bool)field;
 715
 716                         return usage_attribute;
 717                 }
 718
 719                 /// <summary>
 720                 /// Returns custom name of indexer
 721                 /// </summary>
 722                 public string GetIndexerAttributeValue (EmitContext ec)
 723                 {
 724                         if (pos_values == null)
 725                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 726                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 727                                 Resolve (ec);
 728
 729                         if (resolve_error)
 730                                 return null;
 731
 732                         return pos_values [0] as string;
 733                 }
 734
 735                 /// <summary>
 736                 /// Returns condition of ConditionalAttribute
 737                 /// </summary>
 738                 public string GetConditionalAttributeValue (EmitContext ec)
 739                 {
 740                         if (pos_values == null)
 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                         if (resolve_error)
 746                                 return null;
 747
 748                         return (string)pos_values [0];
 749                 }
 750
 751                 /// <summary>
 752                 /// Creates the instance of ObsoleteAttribute from this attribute instance
 753                 /// </summary>
 754                 public ObsoleteAttribute GetObsoleteAttribute (EmitContext ec)
 755                 {
 756                         if (pos_values == null)
 757                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 758                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 759                                 Resolve (ec);
 760
 761                         if (resolve_error)
 762                                 return null;
 763
 764                         if (pos_values == null || pos_values.Length == 0)
 765                                 return new ObsoleteAttribute ();
 766
 767                         if (pos_values.Length == 1)
 768                                 return new ObsoleteAttribute ((string)pos_values [0]);
 769
 770                         return new ObsoleteAttribute ((string)pos_values [0], (bool)pos_values [1]);
 771                 }
 772
 773                 /// <summary>
 774                 /// Returns value of CLSCompliantAttribute contructor parameter but because the method can be called
 775                 /// before ApplyAttribute. We need to resolve the arguments.
 776                 /// This situation occurs when class deps is differs from Emit order.
 777                 /// </summary>
 778                 public bool GetClsCompliantAttributeValue (EmitContext ec)
 779                 {
 780                         if (pos_values == null)
 781                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
 782                                 // But because a lot of attribute class code must be rewritten will be better to wait...
 783                                 Resolve (ec);
 784
 785                         if (resolve_error)
 786                                 return false;
 787
 788                         return (bool)pos_values [0];
 789                 }
 790
 791                 /// <summary>
 792                 /// Tests permitted SecurityAction for assembly or other types
 793                 /// </summary>
 794                 public bool CheckSecurityActionValidity (bool for_assembly)
 795                 {
 796                         SecurityAction action  = GetSecurityActionValue ();
 797
 798                         if ((action == SecurityAction.RequestMinimum || action == SecurityAction.RequestOptional || action == SecurityAction.RequestRefuse) && for_assembly)
 799                                 return true;
 800
 801                         if (!for_assembly) {
 802                                 if (action < SecurityAction.Demand || action > SecurityAction.InheritanceDemand) {
 803                                         Error_AttributeEmitError ("SecurityAction is out of range");
 804                                         return false;
 805                                 }
 806
 807                                 if ((action != SecurityAction.RequestMinimum && action != SecurityAction.RequestOptional && action != SecurityAction.RequestRefuse) && !for_assembly)
 808                                         return true;
 809                         }
 810
 811                         Error_AttributeEmitError (String.Concat ("SecurityAction '", action, "' is not valid for this declaration"));
 812                         return false;
 813                 }
 814
 815                 System.Security.Permissions.SecurityAction GetSecurityActionValue ()
 816                 {
 817                         return (SecurityAction)pos_values [0];
 818                 }
 819
 820                 /// <summary>
 821                 /// Creates instance of SecurityAttribute class and add result of CreatePermission method to permission table.
 822                 /// </summary>
 823                 /// <returns></returns>
 824                 public void ExtractSecurityPermissionSet (ListDictionary permissions)
 825                 {
 826                         Type orig_assembly_type = null;
 827
 828                         if (TypeManager.LookupDeclSpace (Type) != null) {
 829                                 if (!RootContext.StdLib) {
 830                                         orig_assembly_type = Type.GetType (Type.FullName);
 831                                 } else {
 832                                         string orig_version_path = Environment.GetEnvironmentVariable ("__SECURITY_BOOTSTRAP_DB");
 833                                         if (orig_version_path == null) {
 834                                                 Error_AttributeEmitError ("security custom attributes can not be referenced from defining assembly");
 835                                                 return;
 836                                         }
 837
 838                                         if (orig_sec_assembly == null) {
 839                                                 string file = Path.Combine (orig_version_path, Driver.OutputFile);
 840                                                 orig_sec_assembly = Assembly.LoadFile (file);
 841                                         }
 842
 843                                         orig_assembly_type = orig_sec_assembly.GetType (Type.FullName, true);
 844                                         if (orig_assembly_type == null) {
 845                                                 Report.Warning (-112, 1, Location, "Self-referenced security attribute `{0}' was not found in previous version of assembly");
 846                                                 return;
 847                                         }
 848                                 }
 849                         }
 850
 851                         SecurityAttribute sa;
 852                         // For all non-selfreferencing security attributes we can avoid all hacks
 853                         if (orig_assembly_type == null) {
 854                                 sa = (SecurityAttribute) Activator.CreateInstance (Type, pos_values);
 855
 856                                 if (prop_info_arr != null) {
 857                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 858                                                 PropertyInfo pi = prop_info_arr [i];
 859                                                 pi.SetValue (sa, prop_values_arr [i], null);
 860                                         }
 861                                 }
 862                         } else {
 863                                 // HACK: All security attributes have same ctor syntax
 864                                 sa = (SecurityAttribute) Activator.CreateInstance (orig_assembly_type, new object[] { GetSecurityActionValue () } );
 865
 866                                 // All types are from newly created assembly but for invocation with old one we need to convert them
 867                                 if (prop_info_arr != null) {
 868                                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 869                                                 PropertyInfo emited_pi = prop_info_arr [i];
 870                                                 PropertyInfo pi = orig_assembly_type.GetProperty (emited_pi.Name, emited_pi.PropertyType);
 871
 872                                                 object old_instance = pi.PropertyType.IsEnum ?
 873                                                         System.Enum.ToObject (pi.PropertyType, prop_values_arr [i]) :
 874                                                         prop_values_arr [i];
 875
 876                                                 pi.SetValue (sa, old_instance, null);
 877                                         }
 878                                 }
 879                         }
 880
 881                         IPermission perm;
 882                         perm = sa.CreatePermission ();
 883                         SecurityAction action = GetSecurityActionValue ();
 884
 885                         // IS is correct because for corlib we are using an instance from old corlib
 886                         if (!(perm is System.Security.CodeAccessPermission)) {
 887                                 switch (action) {
 888                                         case SecurityAction.Demand:
 889                                                 action = (SecurityAction)13;
 890                                                 break;
 891                                         case SecurityAction.LinkDemand:
 892                                                 action = (SecurityAction)14;
 893                                                 break;
 894                                         case SecurityAction.InheritanceDemand:
 895                                                 action = (SecurityAction)15;
 896                                                 break;
 897                                 }
 898                         }
 899
 900                         PermissionSet ps = (PermissionSet)permissions [action];
 901                         if (ps == null) {
 902                                 if (sa is PermissionSetAttribute)
 903                                         ps = new PermissionSet (sa.Unrestricted ? PermissionState.Unrestricted : PermissionState.None);
 904                                 else
 905                                         ps = new PermissionSet (PermissionState.None);
 906
 907                                 permissions.Add (action, ps);
 908                         } else if (!ps.IsUnrestricted () && (sa is PermissionSetAttribute) && sa.Unrestricted) {
 909                                 ps = ps.Union (new PermissionSet (PermissionState.Unrestricted));
 910                                 permissions [action] = ps;
 911                         }
 912                         ps.AddPermission (perm);
 913                 }
 914
 915                 object GetValue (object value)
 916                 {
 917                         if (value is EnumConstant)
 918                                 return ((EnumConstant) value).GetValue ();
 919                         else
 920                                 return value;
 921                 }
 922
 923                 object GetPropertyValue (string name)
 924                 {
 925                         if (prop_info_arr == null)
 926                                 return null;
 927
 928                         for (int i = 0; i < prop_info_arr.Length; ++i) {
 929                                 if (prop_info_arr [i].Name == name)
 930                                         return prop_values_arr [i];
 931                         }
 932
 933                         return null;
 934                 }
 935
 936                 object GetFieldValue (string name)
 937                 {
 938                         int i;
 939                         if (field_info_arr == null)
 940                                 return null;
 941                         i = 0;
 942                         foreach (FieldInfo fi in field_info_arr) {
 943                                 if (fi.Name == name)
 944                                         return GetValue (field_values_arr [i]);
 945                                 i++;
 946                         }
 947                         return null;
 948                 }
 949
 950                 public UnmanagedMarshal GetMarshal (Attributable attr)
 951                 {
 952                         UnmanagedType UnmanagedType = (UnmanagedType)System.Enum.Parse (typeof (UnmanagedType), pos_values [0].ToString ());
 953
 954                         object value = GetFieldValue ("SizeParamIndex");
 955                         if (value != null && UnmanagedType != UnmanagedType.LPArray) {
 956                                 Error_AttributeEmitError ("SizeParamIndex field is not valid for the specified unmanaged type");
 957                                 return null;
 958                         }
 959
 960                         object o = GetFieldValue ("ArraySubType");
 961                         UnmanagedType array_sub_type = o == null ? UnmanagedType.I4 : (UnmanagedType) o;
 962
 963                         switch (UnmanagedType) {
 964                         case UnmanagedType.CustomMarshaler: {
 965                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",
 966                                                                        BindingFlags.Static | BindingFlags.Public);
 967                                 if (define_custom == null) {
 968                                         Report.RuntimeMissingSupport (Location, "set marshal info");
 969                                         return null;
 970                                 }
 971
 972                                 object [] args = new object [4];
 973                                 args [0] = GetFieldValue ("MarshalTypeRef");
 974                                 args [1] = GetFieldValue ("MarshalCookie");
 975                                 args [2] = GetFieldValue ("MarshalType");
 976                                 args [3] = Guid.Empty;
 977                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);
 978                         }
 979                         case UnmanagedType.LPArray: {
 980                                 object size_const = GetFieldValue ("SizeConst");
 981                                 object size_param_index = GetFieldValue ("SizeParamIndex");
 982
 983                                 if ((size_const != null) || (size_param_index != null)) {
 984                                         MethodInfo define_array = typeof (UnmanagedMarshal).GetMethod ("DefineLPArrayInternal", BindingFlags.Static | BindingFlags.Public | BindingFlags.NonPublic);
 985                                         if (define_array == null) {
 986                                                 Report.RuntimeMissingSupport (Location, "set marshal info");
 987                                                 return null;
 988                                         }
 989
 990                                         object [] args = new object [3];
 991                                         args [0] = array_sub_type;
 992                                         args [1] = size_const == null ? -1 : size_const;
 993                                         args [2] = size_param_index == null ? -1 : size_param_index;
 994                                         return (UnmanagedMarshal) define_array.Invoke (null, args);
 995                                 }
 996                                 else
 997                                         return UnmanagedMarshal.DefineLPArray (array_sub_type);
 998                         }
 999                         case UnmanagedType.SafeArray:
1000                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);
1001
1002                         case UnmanagedType.ByValArray:
1003                                 FieldMember fm = attr as FieldMember;
1004                                 if (fm == null) {
1005                                         Error_AttributeEmitError ("Specified unmanaged type is only valid on fields");
1006                                         return null;
1007                                 }
1008                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue ("SizeConst"));
1009
1010                         case UnmanagedType.ByValTStr:
1011                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue ("SizeConst"));
1012
1013                         default:
1014                                 return UnmanagedMarshal.DefineUnmanagedMarshal (UnmanagedType);
1015                         }
1016                 }
1017
1018                 public CharSet GetCharSetValue ()
1019                 {
1020                         return (CharSet)System.Enum.Parse (typeof (CharSet), pos_values [0].ToString ());
1021                 }
1022
1023                 public MethodImplOptions GetMethodImplOptions ()
1024                 {
1025                         return (MethodImplOptions)System.Enum.Parse (typeof (MethodImplOptions), pos_values [0].ToString ());
1026                 }
1027
1028                 public LayoutKind GetLayoutKindValue ()
1029                 {
1030                         return (LayoutKind)System.Enum.Parse (typeof (LayoutKind), pos_values [0].ToString ());
1031                 }
1032
1033                 /// <summary>
1034                 /// Emit attribute for Attributable symbol
1035                 /// </summary>
1036                 public void Emit (EmitContext ec, Attributable ias, ListDictionary emitted_attr)
1037                 {
1038                         CustomAttributeBuilder cb = Resolve (ec);
1039                         if (cb == null)
1040                                 return;
1041
1042                         AttributeUsageAttribute usage_attr = GetAttributeUsage (ec);
1043                         if ((usage_attr.ValidOn & Target) == 0) {
1044                                 Report.Error (592, Location, "Attribute `{0}' is not valid on this declaration type. It is valid on `{1}' declarations only",
1045                                         GetSignatureForError (), GetValidTargets ());
1046                                 return;
1047                         }
1048
1049                         try {
1050                                 ias.ApplyAttributeBuilder (this, cb);
1051                         }
1052                         catch (Exception e) {
1053                                 Error_AttributeEmitError (e.Message);
1054                                 return;
1055                         }
1056
1057                         if (!usage_attr.AllowMultiple) {
1058                                 ArrayList emitted_targets = (ArrayList)emitted_attr [Type];
1059                                 if (emitted_targets == null) {
1060                                         emitted_targets = new ArrayList ();
1061                                         emitted_attr.Add (Type, emitted_targets);
1062                                 } else if (emitted_targets.Contains (Target)) {
1063                                         Report.Error (579, Location, "Duplicate `{0}' attribute", GetSignatureForError ());
1064                                         return;
1065                                 }
1066                                 emitted_targets.Add (Target);
1067                         }
1068
1069                         if (!RootContext.VerifyClsCompliance)
1070                                 return;
1071
1072                         // Here we are testing attribute arguments for array usage (error 3016)
1073                         if (ias.IsClsCompliaceRequired (ec.DeclSpace)) {
1074                                 if (Arguments == null)
1075                                         return;
1076
1077                                 ArrayList pos_args = (ArrayList) Arguments [0];
1078                                 if (pos_args != null) {
1079                                         foreach (Argument arg in pos_args) {
1080                                                 // Type is undefined (was error 246)
1081                                                 if (arg.Type == null)
1082                                                         return;
1083
1084                                                 if (arg.Type.IsArray) {
1085                                                         Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1086                                                         return;
1087                                                 }
1088                                         }
1089                                 }
1090
1091                                 if (Arguments.Count < 2)
1092                                         return;
1093
1094                                 ArrayList named_args = (ArrayList) Arguments [1];
1095                                 foreach (DictionaryEntry de in named_args) {
1096                                         Argument arg  = (Argument) de.Value;
1097
1098                                         // Type is undefined (was error 246)
1099                                         if (arg.Type == null)
1100                                                 return;
1101
1102                                         if (arg.Type.IsArray) {
1103                                                 Report.Error (3016, Location, "Arrays as attribute arguments are not CLS-compliant");
1104                                                 return;
1105                                         }
1106                                 }
1107                         }
1108                 }
1109
1110                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,
1111                                                           MethodAttributes flags, Type ret_type, Type [] param_types)
1112                 {
1113                         if (pos_values == null)
1114                                 // TODO: It is not neccessary to call whole Resolve (ApplyAttribute does it now) we need only ctor args.
1115                                 // But because a lot of attribute class code must be rewritten will be better to wait...
1116                                 Resolve (ec);
1117
1118                         if (resolve_error)
1119                                 return null;
1120
1121                         string dll_name = (string)pos_values [0];
1122
1123                         // Default settings
1124                         CallingConvention cc = CallingConvention.Winapi;
1125                         CharSet charset = CodeGen.Module.DefaultCharSet;
1126                         bool preserve_sig = true;
1127                         string entry_point = name;
1128                         bool best_fit_mapping = false;
1129                         bool throw_on_unmappable = false;
1130                         bool exact_spelling = false;
1131                         bool set_last_error = false;
1132
1133                         bool best_fit_mapping_set = false;
1134                         bool throw_on_unmappable_set = false;
1135                         bool exact_spelling_set = false;
1136                         bool set_last_error_set = false;
1137
1138                         MethodInfo set_best_fit = null;
1139                         MethodInfo set_throw_on = null;
1140                         MethodInfo set_exact_spelling = null;
1141                         MethodInfo set_set_last_error = null;
1142
1143                         if (field_info_arr != null) {
1144
1145                                 for (int i = 0; i < field_info_arr.Length; i++) {
1146                                         switch (field_info_arr [i].Name) {
1147                                                 case "BestFitMapping":
1148                                                         best_fit_mapping = (bool) field_values_arr [i];
1149                                                         best_fit_mapping_set = true;
1150                                                         break;
1151                                                 case "CallingConvention":
1152                                                         cc = (CallingConvention) field_values_arr [i];
1153                                                         break;
1154                                                 case "CharSet":
1155                                                         charset = (CharSet) field_values_arr [i];
1156                                                         break;
1157                                                 case "EntryPoint":
1158                                                         entry_point = (string) field_values_arr [i];
1159                                                         break;
1160                                                 case "ExactSpelling":
1161                                                         exact_spelling = (bool) field_values_arr [i];
1162                                                         exact_spelling_set = true;
1163                                                         break;
1164                                                 case "PreserveSig":
1165                                                         preserve_sig = (bool) field_values_arr [i];
1166                                                         break;
1167                                                 case "SetLastError":
1168                                                         set_last_error = (bool) field_values_arr [i];
1169                                                         set_last_error_set = true;
1170                                                         break;
1171                                                 case "ThrowOnUnmappableChar":
1172                                                         throw_on_unmappable = (bool) field_values_arr [i];
1173                                                         throw_on_unmappable_set = true;
1174                                                         break;
1175                                                 default:
1176                                                         throw new InternalErrorException (field_info_arr [i].ToString ());
1177                                         }
1178                                 }
1179                         }
1180
1181                         if (throw_on_unmappable_set || best_fit_mapping_set || exact_spelling_set || set_last_error_set) {
1182                                 set_best_fit = typeof (MethodBuilder).GetMethod ("set_BestFitMapping", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1183                                 set_throw_on = typeof (MethodBuilder).GetMethod ("set_ThrowOnUnmappableChar", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1184                                 set_exact_spelling = typeof (MethodBuilder).GetMethod ("set_ExactSpelling", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1185                                 set_set_last_error = typeof (MethodBuilder).GetMethod ("set_SetLastError", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
1186
1187                                 if ((set_best_fit == null) || (set_throw_on == null) || (set_exact_spelling == null) || (set_set_last_error == null)) {
1188                                         Report.Error (-1, Location,
1189                                                                   "The ThrowOnUnmappableChar, BestFitMapping, SetLastError, and ExactSpelling attributes can only be emitted when running on the mono runtime.");
1190                                         return null;
1191                                 }
1192                         }
1193
1194                         try {
1195                                 MethodBuilder mb = builder.DefinePInvokeMethod (
1196                                         name, dll_name, entry_point, flags | MethodAttributes.HideBySig | MethodAttributes.PinvokeImpl,
1197                                         CallingConventions.Standard, ret_type, param_types, cc, charset);
1198
1199                                 if (preserve_sig)
1200                                         mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);
1201
1202                                 if (throw_on_unmappable_set)
1203                                         set_throw_on.Invoke (mb, 0, null, new object [] { throw_on_unmappable }, null);
1204                                 if (best_fit_mapping_set)
1205                                         set_best_fit.Invoke (mb, 0, null, new object [] { best_fit_mapping }, null);
1206                                 if (exact_spelling_set)
1207                                         set_exact_spelling.Invoke  (mb, 0, null, new object [] { exact_spelling }, null);
1208                                 if (set_last_error_set)
1209                                         set_set_last_error.Invoke  (mb, 0, null, new object [] { set_last_error }, null);
1210
1211                                 return mb;
1212                         }
1213                         catch (ArgumentException e) {
1214                                 Error_AttributeEmitError (e.Message);
1215                                 return null;
1216                         }
1217                 }
1218
1219                 private Expression GetValue ()
1220                 {
1221                         if ((Arguments == null) || (Arguments.Count < 1))
1222                                 return null;
1223                         ArrayList al = (ArrayList) Arguments [0];
1224                         if ((al == null) || (al.Count < 1))
1225                                 return null;
1226                         Argument arg = (Argument) al [0];
1227                         if ((arg == null) || (arg.Expr == null))
1228                                 return null;
1229                         return arg.Expr;
1230                 }
1231
1232                 public string GetString ()
1233                 {
1234                         Expression e = GetValue ();
1235                         if (e is StringLiteral)
1236                                 return (e as StringLiteral).Value;
1237                         return null;
1238                 }
1239
1240                 public bool GetBoolean ()
1241                 {
1242                         Expression e = GetValue ();
1243                         if (e is BoolLiteral)
1244                                 return (e as BoolLiteral).Value;
1245                         return false;
1246                 }
1247         }
1248
1249
1250         /// <summary>
1251         /// For global attributes (assembly, module) we need special handling.
1252         /// Attributes can be located in the several files
1253         /// </summary>
1254         public class GlobalAttribute: Attribute
1255         {
1256                 public readonly NamespaceEntry ns;
1257
1258                 public GlobalAttribute (TypeContainer container, string target,
1259                                         Expression left_expr, string identifier, ArrayList args, Location loc):
1260                         base (target, left_expr, identifier, args, loc)
1261                 {
1262                         ns = container.NamespaceEntry;
1263                 }
1264
1265                 void Enter ()
1266                 {
1267                         // RootContext.Tree.Types has a single NamespaceEntry which gets overwritten
1268                         // each time a new file is parsed.  However, we need to use the NamespaceEntry
1269                         // in effect where the attribute was used.  Since code elsewhere cannot assume
1270                         // that the NamespaceEntry is right, just overwrite it.
1271                         //
1272                         // Precondition: RootContext.Tree.Types == null
1273
1274                         if (RootContext.Tree.Types.NamespaceEntry != null)
1275                                 throw new InternalErrorException (Location + " non-null NamespaceEntry");
1276
1277                         RootContext.Tree.Types.NamespaceEntry = ns;
1278                 }
1279
1280                 void Leave ()
1281                 {
1282                         RootContext.Tree.Types.NamespaceEntry = null;
1283                 }
1284
1285                 protected override FullNamedExpression ResolveAsTypeStep (Expression expr, EmitContext ec, bool silent)
1286                 {
1287                         try {
1288                                 Enter ();
1289                                 return base.ResolveAsTypeStep (expr, ec, silent);
1290                         }
1291                         finally {
1292                                 Leave ();
1293                         }
1294                 }
1295
1296
1297                 protected override FullNamedExpression ResolveAsTypeTerminal (Expression expr, EmitContext ec, bool silent)
1298                 {
1299                         try {
1300                                 Enter ();
1301                                 return base.ResolveAsTypeTerminal (expr, ec, silent);
1302                         }
1303                         finally {
1304                                 Leave ();
1305                         }
1306                 }
1307
1308                 protected override ConstructorInfo ResolveArguments (EmitContext ec)
1309                 {
1310                         try {
1311                                 Enter ();
1312                                 return base.ResolveArguments (ec);
1313                         }
1314                         finally {
1315                                 Leave ();
1316                         }
1317                 }
1318         }
1319
1320         public class Attributes {
1321                 public ArrayList Attrs;
1322
1323                 public Attributes (Attribute a)
1324                 {
1325                         Attrs = new ArrayList ();
1326                         Attrs.Add (a);
1327                 }
1328
1329                 public Attributes (ArrayList attrs)
1330                 {
1331                         Attrs = attrs;
1332                 }
1333
1334                 public void AddAttributes (ArrayList attrs)
1335                 {
1336                         Attrs.AddRange (attrs);
1337                 }
1338
1339                 /// <summary>
1340                 /// Checks whether attribute target is valid for the current element
1341                 /// </summary>
1342                 public bool CheckTargets (Attributable member)
1343                 {
1344                         string[] valid_targets = member.ValidAttributeTargets;
1345                         foreach (Attribute a in Attrs) {
1346                                 if (a.ExplicitTarget == null || a.ExplicitTarget == valid_targets [0]) {
1347                                         a.Target = member.AttributeTargets;
1348                                         continue;
1349                                 }
1350
1351                                 // TODO: we can skip the first item
1352                                 if (((IList) valid_targets).Contains (a.ExplicitTarget)) {
1353                                         switch (a.ExplicitTarget) {
1354                                                 case "return": a.Target = AttributeTargets.ReturnValue; continue;
1355                                                 case "param": a.Target = AttributeTargets.Parameter; continue;
1356                                                 case "field": a.Target = AttributeTargets.Field; continue;
1357                                                 case "method": a.Target = AttributeTargets.Method; continue;
1358                                                 case "property": a.Target = AttributeTargets.Property; continue;
1359                                         }
1360                                         throw new InternalErrorException ("Unknown explicit target: " + a.ExplicitTarget);
1361                                 }
1362
1363                                 StringBuilder sb = new StringBuilder ();
1364                                 foreach (string s in valid_targets) {
1365                                         sb.Append (s);
1366                                         sb.Append (", ");
1367                                 }
1368                                 sb.Remove (sb.Length - 2, 2);
1369                                 Report.Error (657, a.Location, "`{0}' is not a valid attribute location for this declaration. Valid attribute locations for this declaration are `{1}'", a.ExplicitTarget, sb.ToString ());
1370                                 return false;
1371                         }
1372                         return true;
1373                 }
1374
1375                 public Attribute Search (Type t, EmitContext ec)
1376                 {
1377                         foreach (Attribute a in Attrs) {
1378                                 if (a.ResolveType (ec) == t)
1379                                         return a;
1380                         }
1381                         return null;
1382                 }
1383
1384                 /// <summary>
1385                 /// Returns all attributes of type 't'. Use it when attribute is AllowMultiple = true
1386                 /// </summary>
1387                 public Attribute[] SearchMulti (Type t, EmitContext ec)
1388                 {
1389                         ArrayList ar = null;
1390
1391                         foreach (Attribute a in Attrs) {
1392                                 if (a.ResolveType (ec) == t) {
1393                                         if (ar == null)
1394                                                 ar = new ArrayList ();
1395                                         ar.Add (a);
1396                                 }
1397                         }
1398
1399                         return ar == null ? null : ar.ToArray (typeof (Attribute)) as Attribute[];
1400                 }
1401
1402                 public void Emit (EmitContext ec, Attributable ias)
1403                 {
1404                         CheckTargets (ias);
1405
1406                         ListDictionary ld = new ListDictionary ();
1407
1408                         foreach (Attribute a in Attrs)
1409                                 a.Emit (ec, ias, ld);
1410                 }
1411
1412                 public bool Contains (Type t, EmitContext ec)
1413                 {
1414                         return Search (t, ec) != null;
1415                 }
1416         }
1417
1418         /// <summary>
1419         /// Helper class for attribute verification routine.
1420         /// </summary>
1421         sealed class AttributeTester
1422         {
1423                 static PtrHashtable analyzed_types = new PtrHashtable ();
1424                 static PtrHashtable analyzed_types_obsolete = new PtrHashtable ();
1425                 static PtrHashtable analyzed_member_obsolete = new PtrHashtable ();
1426                 static PtrHashtable analyzed_method_excluded = new PtrHashtable ();
1427
1428 #if NET_2_0
1429                 static PtrHashtable fixed_buffer_cache = new PtrHashtable ();
1430 #endif
1431
1432                 static object TRUE = new object ();
1433                 static object FALSE = new object ();
1434
1435                 private AttributeTester ()
1436                 {
1437                 }
1438
1439                 public enum Result {
1440                         Ok,
1441                         RefOutArrayError,
1442                         ArrayArrayError
1443                 }
1444
1445                 /// <summary>
1446                 /// Returns true if parameters of two compared methods are CLS-Compliant.
1447                 /// It tests differing only in ref or out, or in array rank.
1448                 /// </summary>
1449                 public static Result AreOverloadedMethodParamsClsCompliant (Type[] types_a, Type[] types_b)
1450                 {
1451                         if (types_a == null || types_b == null)
1452                                 return Result.Ok;
1453
1454                         if (types_a.Length != types_b.Length)
1455                                 return Result.Ok;
1456
1457                         Result result = Result.Ok;
1458                         for (int i = 0; i < types_b.Length; ++i) {
1459                                 Type aType = types_a [i];
1460                                 Type bType = types_b [i];
1461
1462                                 if (aType.IsArray && bType.IsArray) {
1463                                         Type a_el_type = aType.GetElementType ();
1464                                         Type b_el_type = bType.GetElementType ();
1465                                         if (aType.GetArrayRank () != bType.GetArrayRank () && a_el_type == b_el_type) {
1466                                                 result = Result.RefOutArrayError;
1467                                                 continue;
1468                                         }
1469
1470                                         if (a_el_type.IsArray || b_el_type.IsArray) {
1471                                                 result = Result.ArrayArrayError;
1472                                                 continue;
1473                                         }
1474                                 }
1475
1476                                 Type aBaseType = aType;
1477                                 bool is_either_ref_or_out = false;
1478
1479                                 if (aType.IsByRef || aType.IsPointer) {
1480                                         aBaseType = aType.GetElementType ();
1481                                         is_either_ref_or_out = true;
1482                                 }
1483
1484                                 Type bBaseType = bType;
1485                                 if (bType.IsByRef || bType.IsPointer)
1486                                 {
1487                                         bBaseType = bType.GetElementType ();
1488                                         is_either_ref_or_out = !is_either_ref_or_out;
1489                                 }
1490
1491                                 if (aBaseType != bBaseType)
1492                                         return Result.Ok;
1493
1494                                 if (is_either_ref_or_out)
1495                                         result = Result.RefOutArrayError;
1496                         }
1497                         return result;
1498                 }
1499
1500                 /// <summary>
1501                 /// Goes through all parameters and test if they are CLS-Compliant.
1502                 /// </summary>
1503                 public static bool AreParametersCompliant (Parameter[] fixedParameters, Location loc)
1504                 {
1505                         if (fixedParameters == null)
1506                                 return true;
1507
1508                         foreach (Parameter arg in fixedParameters) {
1509                                 if (!AttributeTester.IsClsCompliant (arg.ParameterType)) {
1510                                         Report.Error (3001, loc, "Argument type `{0}' is not CLS-compliant", arg.GetSignatureForError ());
1511                                         return false;
1512                                 }
1513                         }
1514                         return true;
1515                 }
1516
1517
1518                 /// <summary>
1519                 /// This method tests the CLS compliance of external types. It doesn't test type visibility.
1520                 /// </summary>
1521                 public static bool IsClsCompliant (Type type)
1522                 {
1523                         if (type == null)
1524                                 return true;
1525
1526                         object type_compliance = analyzed_types[type];
1527                         if (type_compliance != null)
1528                                 return type_compliance == TRUE;
1529
1530                         if (type.IsPointer) {
1531                                 analyzed_types.Add (type, null);
1532                                 return false;
1533                         }
1534
1535                         bool result;
1536                         if (type.IsArray || type.IsByRef)       {
1537                                 result = IsClsCompliant (TypeManager.GetElementType (type));
1538                         } else {
1539                                 result = AnalyzeTypeCompliance (type);
1540                         }
1541                         analyzed_types.Add (type, result ? TRUE : FALSE);
1542                         return result;
1543                 }
1544
1545                 /// <summary>
1546                 /// Returns IFixedBuffer implementation if field is fixed buffer else null.
1547                 /// </summary>
1548                 public static IFixedBuffer GetFixedBuffer (FieldInfo fi)
1549                 {
1550                         FieldBase fb = TypeManager.GetField (fi);
1551                         if (fb != null) {
1552                                 return fb as IFixedBuffer;
1553                         }
1554
1555 #if NET_2_0
1556                         object o = fixed_buffer_cache [fi];
1557                         if (o == null) {
1558                                 if (System.Attribute.GetCustomAttribute (fi, TypeManager.fixed_buffer_attr_type) == null) {
1559                                         fixed_buffer_cache.Add (fi, FALSE);
1560                                         return null;
1561                                 }
1562
1563                                 IFixedBuffer iff = new FixedFieldExternal (fi);
1564                                 fixed_buffer_cache.Add (fi, iff);
1565                                 return iff;
1566                         }
1567
1568                         if (o == FALSE)
1569                                 return null;
1570
1571                         return (IFixedBuffer)o;
1572 #else
1573                         return null;
1574 #endif
1575                 }
1576
1577                 public static void VerifyModulesClsCompliance ()
1578                 {
1579                         Module[] modules = TypeManager.Modules;
1580                         if (modules == null)
1581                                 return;
1582
1583                         // The first module is generated assembly
1584                         for (int i = 1; i < modules.Length; ++i) {
1585                                 Module module = modules [i];
1586                                 if (!IsClsCompliant (module)) {
1587                                         Report.Error (3013, "Added modules must be marked with the CLSCompliant attribute to match the assembly", module.Name);
1588                                         return;
1589                                 }
1590                         }
1591                 }
1592
1593                 public static Type GetImportedIgnoreCaseClsType (string name)
1594                 {
1595                         foreach (Assembly a in TypeManager.GetAssemblies ()) {
1596                                 Type t = a.GetType (name, false, true);
1597                                 if (t == null)
1598                                         continue;
1599
1600                                 if (IsClsCompliant (t))
1601                                         return t;
1602                         }
1603                         return null;
1604                 }
1605
1606                 static bool IsClsCompliant (ICustomAttributeProvider attribute_provider)
1607                 {
1608                         object[] CompliantAttribute = attribute_provider.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1609                         if (CompliantAttribute.Length == 0)
1610                                 return false;
1611
1612                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1613                 }
1614
1615                 static bool AnalyzeTypeCompliance (Type type)
1616                 {
1617                         DeclSpace ds = TypeManager.LookupDeclSpace (type);
1618                         if (ds != null) {
1619                                 return ds.IsClsCompliaceRequired (ds.Parent);
1620                         }
1621
1622                         object[] CompliantAttribute = type.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
1623                         if (CompliantAttribute.Length == 0)
1624                                 return IsClsCompliant (type.Assembly);
1625
1626                         return ((CLSCompliantAttribute)CompliantAttribute[0]).IsCompliant;
1627                 }
1628
1629                 /// <summary>
1630                 /// Returns instance of ObsoleteAttribute when type is obsolete
1631                 /// </summary>
1632                 public static ObsoleteAttribute GetObsoleteAttribute (Type type)
1633                 {
1634                         object type_obsolete = analyzed_types_obsolete [type];
1635                         if (type_obsolete == FALSE)
1636                                 return null;
1637
1638                         if (type_obsolete != null)
1639                                 return (ObsoleteAttribute)type_obsolete;
1640
1641                         ObsoleteAttribute result = null;
1642                         if (type.IsByRef || type.IsArray || type.IsPointer) {
1643                                 result = GetObsoleteAttribute (TypeManager.GetElementType (type));
1644                         } else {
1645                                 DeclSpace type_ds = TypeManager.LookupDeclSpace (type);
1646
1647                                 // Type is external, we can get attribute directly
1648                                 if (type_ds == null) {
1649                                         object[] attribute = type.GetCustomAttributes (TypeManager.obsolete_attribute_type, false);
1650                                         if (attribute.Length == 1)
1651                                                 result = (ObsoleteAttribute)attribute [0];
1652                                 } else {
1653                                         result = type_ds.GetObsoleteAttribute (type_ds);
1654                                 }
1655                         }
1656
1657                         analyzed_types_obsolete.Add (type, result == null ? FALSE : result);
1658                         return result;
1659                 }
1660
1661                 /// <summary>
1662                 /// Returns instance of ObsoleteAttribute when method is obsolete
1663                 /// </summary>
1664                 public static ObsoleteAttribute GetMethodObsoleteAttribute (MethodBase mb)
1665                 {
1666                         IMethodData mc = TypeManager.GetMethod (mb);
1667                         if (mc != null)
1668                                 return mc.GetObsoleteAttribute ();
1669
1670                         // compiler generated methods are not registered by AddMethod
1671                         if (mb.DeclaringType is TypeBuilder)
1672                                 return null;
1673
1674                         PropertyInfo pi = PropertyExpr.AccessorTable [mb] as PropertyInfo;
1675                         if (pi != null)
1676                                 return GetMemberObsoleteAttribute (pi);
1677
1678                         return GetMemberObsoleteAttribute (mb);
1679                 }
1680
1681                 /// <summary>
1682                 /// Returns instance of ObsoleteAttribute when member is obsolete
1683                 /// </summary>
1684                 public static ObsoleteAttribute GetMemberObsoleteAttribute (MemberInfo mi)
1685                 {
1686                         object type_obsolete = analyzed_member_obsolete [mi];
1687                         if (type_obsolete == FALSE)
1688                                 return null;
1689
1690                         if (type_obsolete != null)
1691                                 return (ObsoleteAttribute)type_obsolete;
1692
1693                         ObsoleteAttribute oa = System.Attribute.GetCustomAttribute (mi, TypeManager.obsolete_attribute_type, false) as ObsoleteAttribute;
1694                         analyzed_member_obsolete.Add (mi, oa == null ? FALSE : oa);
1695                         return oa;
1696                 }
1697
1698                 /// <summary>
1699                 /// Common method for Obsolete error/warning reporting.
1700                 /// </summary>
1701                 public static void Report_ObsoleteMessage (ObsoleteAttribute oa, string member, Location loc)
1702                 {
1703                         if (oa.IsError) {
1704                                 Report.Error (619, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1705                                 return;
1706                         }
1707
1708                         if (oa.Message == null) {
1709                                 Report.Warning (612, loc, "`{0}' is obsolete", member);
1710                                 return;
1711                         }
1712                         if (RootContext.WarningLevel >= 2)
1713                                 Report.Warning (618, loc, "`{0}' is obsolete: `{1}'", member, oa.Message);
1714                 }
1715
1716                 public static bool IsConditionalMethodExcluded (MethodBase mb)
1717                 {
1718                         object excluded = analyzed_method_excluded [mb];
1719                         if (excluded != null)
1720                                 return excluded == TRUE ? true : false;
1721
1722                         ConditionalAttribute[] attrs = mb.GetCustomAttributes (TypeManager.conditional_attribute_type, true) as ConditionalAttribute[];
1723                         if (attrs.Length == 0) {
1724                                 analyzed_method_excluded.Add (mb, FALSE);
1725                                 return false;
1726                         }
1727
1728                         foreach (ConditionalAttribute a in attrs) {
1729                                 if (RootContext.AllDefines.Contains (a.ConditionString)) {
1730                                         analyzed_method_excluded.Add (mb, FALSE);
1731                                         return false;
1732                                 }
1733                         }
1734                         analyzed_method_excluded.Add (mb, TRUE);
1735                         return true;
1736                 }
1737
1738                 /// <summary>
1739                 /// Analyzes class whether it has attribute which has ConditionalAttribute
1740                 /// and its condition is not defined.
1741                 /// </summary>
1742                 public static bool IsAttributeExcluded (Type type)
1743                 {
1744                         if (!type.IsClass)
1745                                 return false;
1746
1747                         Class class_decl = TypeManager.LookupDeclSpace (type) as Class;
1748
1749                         // TODO: add caching
1750                         // TODO: merge all Type bases attribute caching to one cache to save memory
1751                         if (class_decl == null) {
1752                                 object[] attributes = type.GetCustomAttributes (TypeManager.conditional_attribute_type, false);
1753                                 foreach (ConditionalAttribute ca in attributes) {
1754                                         if (RootContext.AllDefines.Contains (ca.ConditionString))
1755                                                 return false;
1756                                 }
1757                                 return attributes.Length > 0;
1758                         }
1759
1760                         return class_decl.IsExcluded ();
1761                 }
1762         }
1763 }