mcs/mcs/attribute.cs

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