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                 static void Error_AttributeArgumentNotValid (Location loc)\r
  61                 {\r
  62                         Report.Error (182, loc,\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                 /// <summary>\r
 110                 ///   Validates the guid string\r
 111                 /// </summary>\r
 112                 bool ValidateGuid (string guid)\r
 113                 {\r
 114                         try {\r
 115                                 new Guid (guid);\r
 116                                 return true;\r
 117                         } catch {\r
 118                                 Report.Error (647, Location, "Format of GUID is invalid: " + guid);\r
 119                                 return false;\r
 120                         }\r
 121                 }\r
 122 \r
 123                 //\r
 124                 // Given an expression, if the expression is a valid attribute-argument-expression\r
 125                 // returns an object that can be used to encode it, or null on failure.\r
 126                 //\r
 127                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, out object result)\r
 128                 {\r
 129                         if (e is Constant) {\r
 130                                 result = ((Constant) e).GetValue ();\r
 131                                 return true;\r
 132                         } else if (e is TypeOf) {\r
 133                                 result = ((TypeOf) e).TypeArg;\r
 134                                 return true;\r
 135                         } else if (e is ArrayCreation){\r
 136                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();\r
 137                                 if (result != null)\r
 138                                         return true;\r
 139                         }\r
 140 \r
 141                         result = null;\r
 142                         Error_AttributeArgumentNotValid (loc);\r
 143                         return false;\r
 144                 }\r
 145                 \r
 146                 public CustomAttributeBuilder Resolve (EmitContext ec)\r
 147                 {\r
 148                         if (Type == null)\r
 149                                 Type = CheckAttributeType (ec);\r
 150                         if (Type == null)\r
 151                                 return null;\r
 152 \r
 153                         bool MethodImplAttr = false;\r
 154                         bool MarshalAsAttr = false;\r
 155                         bool GuidAttr = false;\r
 156                         UsageAttr = false;\r
 157 \r
 158                         bool DoCompares = true;\r
 159                         if (Type == TypeManager.attribute_usage_type)\r
 160                                 UsageAttr = true;\r
 161                         else if (Type == TypeManager.methodimpl_attr_type)\r
 162                                 MethodImplAttr = true;\r
 163                         else if (Type == TypeManager.marshal_as_attr_type)\r
 164                                 MarshalAsAttr = true;\r
 165                         else if (Type == TypeManager.guid_attr_type)\r
 166                                 GuidAttr = true;\r
 167                         else\r
 168                                 DoCompares = false;\r
 169 \r
 170                         // Now we extract the positional and named arguments\r
 171                         \r
 172                         ArrayList pos_args = new ArrayList ();\r
 173                         ArrayList named_args = new ArrayList ();\r
 174                         int pos_arg_count = 0;\r
 175                         \r
 176                         if (Arguments != null) {\r
 177                                 pos_args = (ArrayList) Arguments [0];\r
 178                                 if (pos_args != null)\r
 179                                         pos_arg_count = pos_args.Count;\r
 180                                 if (Arguments.Count > 1)\r
 181                                         named_args = (ArrayList) Arguments [1];\r
 182                         }\r
 183 \r
 184                         object [] pos_values = new object [pos_arg_count];\r
 185 \r
 186                         //\r
 187                         // First process positional arguments \r
 188                         //\r
 189 \r
 190                         int i;\r
 191                         for (i = 0; i < pos_arg_count; i++) {\r
 192                                 Argument a = (Argument) pos_args [i];\r
 193                                 Expression e;\r
 194 \r
 195                                 if (!a.Resolve (ec, Location))\r
 196                                         return null;\r
 197 \r
 198                                 e = a.Expr;\r
 199 \r
 200                                 object val;\r
 201                                 if (!GetAttributeArgumentExpression (e, Location, out val))\r
 202                                         return null;\r
 203                                 \r
 204                                 pos_values [i] = val;\r
 205                                 if (DoCompares){\r
 206                                         if (UsageAttr)\r
 207                                                 this.Targets = (AttributeTargets) pos_values [0];\r
 208                                         else if (MethodImplAttr)\r
 209                                                 this.ImplOptions = (MethodImplOptions) pos_values [0];\r
 210                                         else if (GuidAttr){\r
 211                                                 //\r
 212                                                 // we will later check the validity of the type\r
 213                                                 //\r
 214                                                 if (pos_values [0] is string){\r
 215                                                         if (!ValidateGuid ((string) pos_values [0]))\r
 216                                                                 return null;\r
 217                                                 }\r
 218                                                 \r
 219                                         } else if (MarshalAsAttr)\r
 220                                                 this.UnmanagedType =\r
 221                                                 (System.Runtime.InteropServices.UnmanagedType) pos_values [0];\r
 222                                 }\r
 223                         }\r
 224 \r
 225                         //\r
 226                         // Now process named arguments\r
 227                         //\r
 228 \r
 229                         ArrayList field_infos = null;\r
 230                         ArrayList prop_infos  = null;\r
 231                         ArrayList field_values = null;\r
 232                         ArrayList prop_values = null;\r
 233 \r
 234                         if (named_args.Count > 0) {\r
 235                                 field_infos = new ArrayList ();\r
 236                                 prop_infos  = new ArrayList ();\r
 237                                 field_values = new ArrayList ();\r
 238                                 prop_values = new ArrayList ();\r
 239                         }\r
 240                         \r
 241                         for (i = 0; i < named_args.Count; i++) {\r
 242                                 DictionaryEntry de = (DictionaryEntry) named_args [i];\r
 243                                 string member_name = (string) de.Key;\r
 244                                 Argument a  = (Argument) de.Value;\r
 245                                 Expression e;\r
 246                                 \r
 247                                 if (!a.Resolve (ec, Location))\r
 248                                         return null;\r
 249 \r
 250                                 Expression member = Expression.MemberLookup (\r
 251                                         ec, Type, member_name,\r
 252                                         MemberTypes.Field | MemberTypes.Property,\r
 253                                         BindingFlags.Public | BindingFlags.Instance,\r
 254                                         Location);\r
 255 \r
 256                                 if (member == null || !(member is PropertyExpr || member is FieldExpr)) {\r
 257                                         Error_InvalidNamedArgument (member_name);\r
 258                                         return null;\r
 259                                 }\r
 260 \r
 261                                 e = a.Expr;\r
 262                                 if (member is PropertyExpr) {\r
 263                                         PropertyExpr pe = (PropertyExpr) member;\r
 264                                         PropertyInfo pi = pe.PropertyInfo;\r
 265 \r
 266                                         if (!pi.CanWrite) {\r
 267                                                 Error_InvalidNamedArgument (member_name);\r
 268                                                 return null;\r
 269                                         }\r
 270 \r
 271                                         if (e is Constant) {\r
 272                                                 object o = ((Constant) e).GetValue ();\r
 273                                                 prop_values.Add (o);\r
 274                                                 \r
 275                                                 if (UsageAttr) {\r
 276                                                         if (member_name == "AllowMultiple")\r
 277                                                                 this.AllowMultiple = (bool) o;\r
 278                                                         if (member_name == "Inherited")\r
 279                                                                 this.Inherited = (bool) o;\r
 280                                                 }\r
 281                                                 \r
 282                                         } else if (e is TypeOf) {\r
 283                                                 prop_values.Add (((TypeOf) e).TypeArg);\r
 284                                         } else {\r
 285                                                 Error_AttributeArgumentNotValid (Location);\r
 286                                                 return null;\r
 287                                         }\r
 288                                         \r
 289                                         prop_infos.Add (pi);\r
 290                                         \r
 291                                 } else if (member is FieldExpr) {\r
 292                                         FieldExpr fe = (FieldExpr) member;\r
 293                                         FieldInfo fi = fe.FieldInfo;\r
 294 \r
 295                                         if (fi.IsInitOnly) {\r
 296                                                 Error_InvalidNamedArgument (member_name);\r
 297                                                 return null;\r
 298                                         }\r
 299 \r
 300                                         //\r
 301                                         // Handle charset here, and set the TypeAttributes\r
 302                                         \r
 303                                         if (e is Constant){\r
 304                                                 object value = ((Constant) e).GetValue ();\r
 305                                                 \r
 306                                                 field_values.Add (value);\r
 307                                         } else if (e is TypeOf) {\r
 308                                                 field_values.Add (((TypeOf) e).TypeArg);\r
 309                                         } else {\r
 310                                                 Error_AttributeArgumentNotValid (Location);\r
 311                                                 return null;\r
 312                                         }\r
 313                                         \r
 314                                         field_infos.Add (fi);\r
 315                                 }\r
 316                         }\r
 317 \r
 318                         Expression mg = Expression.MemberLookup (\r
 319                                 ec, Type, ".ctor", MemberTypes.Constructor,\r
 320                                 BindingFlags.Public | BindingFlags.Instance, Location);\r
 321 \r
 322                         if (mg == null) {\r
 323                                 Error_AttributeConstructorMismatch (Location);\r
 324                                 return null;\r
 325                         }\r
 326 \r
 327                         MethodBase constructor = Invocation.OverloadResolve (\r
 328                                 ec, (MethodGroupExpr) mg, pos_args, Location);\r
 329 \r
 330                         if (constructor == null) {\r
 331                                 Error_AttributeConstructorMismatch (Location);\r
 332                                 return null;\r
 333                         }\r
 334 \r
 335                         //\r
 336                         // Now we perform some checks on the positional args as they\r
 337                         // cannot be null for a constructor which expects a parameter\r
 338                         // of type object\r
 339                         //\r
 340 \r
 341                         ParameterData pd = Invocation.GetParameterData (constructor);\r
 342 \r
 343                         int group_in_params_array = Int32.MaxValue;\r
 344                         int pc = pd.Count;\r
 345                         if (pc > 0 && pd.ParameterModifier (pc-1) == Parameter.Modifier.PARAMS)\r
 346                                 group_in_params_array = pc-1;\r
 347                         \r
 348                         for (int j = 0; j < pos_arg_count; ++j) {\r
 349                                 Argument a = (Argument) pos_args [j];\r
 350                                 \r
 351                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {\r
 352                                         Error_AttributeArgumentNotValid (Location);\r
 353                                         return null;\r
 354                                 }\r
 355 \r
 356                                 if (j < group_in_params_array)\r
 357                                         continue;\r
 358                                 \r
 359                                 if (j == group_in_params_array){\r
 360                                         object v = pos_values [j];\r
 361                                         int count = pos_arg_count - j;\r
 362 \r
 363                                         object [] array = new object [count];\r
 364                                         pos_values [j] = array;\r
 365                                         array [0] = v;\r
 366                                 } else {\r
 367                                         object [] array = (object []) pos_values [group_in_params_array];\r
 368 \r
 369                                         array [j - group_in_params_array] = pos_values [j];\r
 370                                 }\r
 371                         }\r
 372 \r
 373                         //\r
 374                         // Adjust the size of the pos_values if it had params\r
 375                         //\r
 376                         if (group_in_params_array != Int32.MaxValue){\r
 377                                 int argc = group_in_params_array+1;\r
 378                                 object [] new_pos_values = new object [argc];\r
 379 \r
 380                                 for (int p = 0; p < argc; p++)\r
 381                                         new_pos_values [p] = pos_values [p];\r
 382                                 pos_values = new_pos_values;\r
 383                         }\r
 384 \r
 385                         try {\r
 386                                 if (named_args.Count > 0) {\r
 387                                         PropertyInfo [] prop_info_arr = new PropertyInfo [prop_infos.Count];\r
 388                                         FieldInfo [] field_info_arr = new FieldInfo [field_infos.Count];\r
 389                                         object [] field_values_arr = new object [field_values.Count];\r
 390                                         object [] prop_values_arr = new object [prop_values.Count];\r
 391 \r
 392                                         field_infos.CopyTo  (field_info_arr, 0);\r
 393                                         field_values.CopyTo (field_values_arr, 0);\r
 394 \r
 395                                         prop_values.CopyTo  (prop_values_arr, 0);\r
 396                                         prop_infos.CopyTo   (prop_info_arr, 0);\r
 397 \r
 398                                         cb = new CustomAttributeBuilder (\r
 399                                                 (ConstructorInfo) constructor, pos_values,\r
 400                                                 prop_info_arr, prop_values_arr,\r
 401                                                 field_info_arr, field_values_arr);\r
 402                                 }\r
 403                                 else\r
 404                                         cb = new CustomAttributeBuilder (\r
 405                                                 (ConstructorInfo) constructor, pos_values);\r
 406                         } catch (NullReferenceException) {\r
 407                                 // \r
 408                                 // Don't know what to do here\r
 409                                 //\r
 410                                 Report.Warning (\r
 411                                         -100, Location, "NullReferenceException while trying to create attribute. Something's wrong!");\r
 412                         } catch (Exception e) {\r
 413                                 //\r
 414                                 // Sample:\r
 415                                 // using System.ComponentModel;\r
 416                                 // [DefaultValue (CollectionChangeAction.Add)]\r
 417                                 // class X { static void Main () {} }\r
 418                                 //\r
 419                                 Report.Warning (\r
 420                                         -23, Location,\r
 421                                         "The compiler can not encode this attribute in .NET due to\n" +\r
 422                                         "\ta bug in the .NET runtime.  Try the Mono runtime.\nThe error was: " + e.Message);\r
 423                         }\r
 424                         \r
 425                         return cb;\r
 426                 }\r
 427 \r
 428                 static string GetValidPlaces (Attribute attr)\r
 429                 {\r
 430                         StringBuilder sb = new StringBuilder ();\r
 431                         AttributeTargets targets = 0;\r
 432                         \r
 433                         TypeContainer a = TypeManager.LookupAttr (attr.Type);\r
 434 \r
 435                         if (a == null) {\r
 436                                 \r
 437                                 System.Attribute [] attrs = null;\r
 438                                 \r
 439                                 try {\r
 440                                         attrs = System.Attribute.GetCustomAttributes (attr.Type);\r
 441                                         \r
 442                                 } catch {\r
 443                                         Report.Error (-20, attr.Location, "Cannot find attribute type " + attr.Name +\r
 444                                                       " (maybe you forgot to set the usage using the" +\r
 445                                                       " AttributeUsage attribute ?).");\r
 446                                         return null;\r
 447                                 }\r
 448                                         \r
 449                                 foreach (System.Attribute tmp in attrs)\r
 450                                         if (tmp is AttributeUsageAttribute) {\r
 451                                                 targets = ((AttributeUsageAttribute) tmp).ValidOn;\r
 452                                                 break;\r
 453                                         }\r
 454                         } else\r
 455                                 targets = a.Targets;\r
 456 \r
 457                         \r
 458                         if ((targets & AttributeTargets.Assembly) != 0)\r
 459                                 sb.Append ("'assembly' ");\r
 460 \r
 461                         if ((targets & AttributeTargets.Class) != 0)\r
 462                                 sb.Append ("'class' ");\r
 463 \r
 464                         if ((targets & AttributeTargets.Constructor) != 0)\r
 465                                 sb.Append ("'constructor' ");\r
 466 \r
 467                         if ((targets & AttributeTargets.Delegate) != 0)\r
 468                                 sb.Append ("'delegate' ");\r
 469 \r
 470                         if ((targets & AttributeTargets.Enum) != 0)\r
 471                                 sb.Append ("'enum' ");\r
 472 \r
 473                         if ((targets & AttributeTargets.Event) != 0)\r
 474                                 sb.Append ("'event' ");\r
 475 \r
 476                         if ((targets & AttributeTargets.Field) != 0)\r
 477                                 sb.Append ("'field' ");\r
 478 \r
 479                         if ((targets & AttributeTargets.Interface) != 0)\r
 480                                 sb.Append ("'interface' ");\r
 481 \r
 482                         if ((targets & AttributeTargets.Method) != 0)\r
 483                                 sb.Append ("'method' ");\r
 484 \r
 485                         if ((targets & AttributeTargets.Module) != 0)\r
 486                                 sb.Append ("'module' ");\r
 487 \r
 488                         if ((targets & AttributeTargets.Parameter) != 0)\r
 489                                 sb.Append ("'parameter' ");\r
 490 \r
 491                         if ((targets & AttributeTargets.Property) != 0)\r
 492                                 sb.Append ("'property' ");\r
 493 \r
 494                         if ((targets & AttributeTargets.ReturnValue) != 0)\r
 495                                 sb.Append ("'return value' ");\r
 496 \r
 497                         if ((targets & AttributeTargets.Struct) != 0)\r
 498                                 sb.Append ("'struct' ");\r
 499 \r
 500                         return sb.ToString ();\r
 501 \r
 502                 }\r
 503 \r
 504                 public static void Error_AttributeNotValidForElement (Attribute a, Location loc)\r
 505                 {\r
 506                         Report.Error (\r
 507                                 592, loc, "Attribute '" + a.Name +\r
 508                                 "' is not valid on this declaration type. " +\r
 509                                 "It is valid on " + GetValidPlaces (a) + "declarations only.");\r
 510                 }\r
 511 \r
 512                 public static bool CheckAttribute (Attribute a, object element)\r
 513                 {\r
 514                         TypeContainer attr = TypeManager.LookupAttr (a.Type);\r
 515                         AttributeTargets targets = 0;\r
 516 \r
 517                         \r
 518                         if (attr == null) {\r
 519                                 System.Attribute [] attrs = null;\r
 520                                 \r
 521                                 try {\r
 522                                         attrs = System.Attribute.GetCustomAttributes (a.Type);\r
 523 \r
 524                                 } catch {\r
 525                                         Report.Error (-20, a.Location, "Cannot find attribute type " + a.Name +\r
 526                                                       " (maybe you forgot to set the usage using the" +\r
 527                                                       " AttributeUsage attribute ?).");\r
 528                                         return false;\r
 529                                 }\r
 530                                         \r
 531                                 foreach (System.Attribute tmp in attrs)\r
 532                                         if (tmp is AttributeUsageAttribute) \r
 533                                                 targets = ((AttributeUsageAttribute) tmp).ValidOn;\r
 534                         } else\r
 535                                 targets = attr.Targets;\r
 536 \r
 537                         if (element is Class) {\r
 538                                 if ((targets & AttributeTargets.Class) != 0)\r
 539                                         return true;\r
 540                                 else\r
 541                                         return false;\r
 542                                 \r
 543                         } else if (element is Struct) {\r
 544                                 if ((targets & AttributeTargets.Struct) != 0)\r
 545                                         return true;\r
 546                                 else\r
 547                                         return false;\r
 548                         } else if (element is Constructor) {\r
 549                                 if ((targets & AttributeTargets.Constructor) != 0)\r
 550                                         return true;\r
 551                                 else\r
 552                                         return false;\r
 553                         } else if (element is Delegate) {\r
 554                                 if ((targets & AttributeTargets.Delegate) != 0)\r
 555                                         return true;\r
 556                                 else\r
 557                                         return false;\r
 558                         } else if (element is Enum) {\r
 559                                 if ((targets & AttributeTargets.Enum) != 0)\r
 560                                         return true;\r
 561                                 else\r
 562                                         return false;\r
 563                         } else if (element is Event || element is InterfaceEvent) {\r
 564                                 if ((targets & AttributeTargets.Event) != 0)\r
 565                                         return true;\r
 566                                 else\r
 567                                         return false;\r
 568                         } else if (element is Field || element is FieldBuilder) {\r
 569                                 if ((targets & AttributeTargets.Field) != 0)\r
 570                                         return true;\r
 571                                 else\r
 572                                         return false;\r
 573                         } else if (element is Interface) {\r
 574                                 if ((targets & AttributeTargets.Interface) != 0)\r
 575                                         return true;\r
 576                                 else\r
 577                                         return false;\r
 578                         } else if (element is Method || element is Operator || element is InterfaceMethod || element is Accessor) {\r
 579                                 if ((targets & AttributeTargets.Method) != 0)\r
 580                                         return true;\r
 581                                 else\r
 582                                         return false;\r
 583                         } else if (element is ParameterBuilder) {\r
 584                                 if ((targets & AttributeTargets.Parameter) != 0)\r
 585                                         return true;\r
 586                                 else\r
 587                                         return false;\r
 588                         } else if (element is Property || element is Indexer ||\r
 589                                    element is InterfaceProperty || element is InterfaceIndexer) {\r
 590                                 if ((targets & AttributeTargets.Property) != 0)\r
 591                                         return true;\r
 592                                 else\r
 593                                         return false;\r
 594                         } else if (element is AssemblyBuilder){\r
 595                                 if ((targets & AttributeTargets.Assembly) != 0)\r
 596                                         return true;\r
 597                                 else\r
 598                                         return false;\r
 599                         }\r
 600 \r
 601                         return false;\r
 602                 }\r
 603 \r
 604                 //\r
 605                 // This method should be invoked to pull the IndexerName attribute from an\r
 606                 // Indexer if it exists.\r
 607                 //\r
 608                 public static string ScanForIndexerName (EmitContext ec, Attributes opt_attrs)\r
 609                 {\r
 610                         if (opt_attrs == null)\r
 611                                 return null;\r
 612                         if (opt_attrs.AttributeSections == null)\r
 613                                 return null;\r
 614 \r
 615                         foreach (AttributeSection asec in opt_attrs.AttributeSections) {\r
 616                                 if (asec.Attributes == null)\r
 617                                         continue;\r
 618 \r
 619                                 foreach (Attribute a in asec.Attributes){\r
 620                                         if (a.ResolveType (ec) == null)\r
 621                                                 return null;\r
 622                                         \r
 623                                         if (a.Type != TypeManager.indexer_name_type)\r
 624                                                 continue;\r
 625 \r
 626                                         //\r
 627                                         // So we have found an IndexerName, pull the data out.\r
 628                                         //\r
 629                                         if (a.Arguments == null || a.Arguments [0] == null){\r
 630                                                 Error_AttributeConstructorMismatch (a.Location);\r
 631                                                 return null;\r
 632                                         }\r
 633                                         ArrayList pos_args = (ArrayList) a.Arguments [0];\r
 634                                         if (pos_args.Count == 0){\r
 635                                                 Error_AttributeConstructorMismatch (a.Location);\r
 636                                                 return null;\r
 637                                         }\r
 638                                         \r
 639                                         Argument arg = (Argument) pos_args [0];\r
 640                                         if (!arg.Resolve (ec, a.Location))\r
 641                                                 return null;\r
 642                                         \r
 643                                         Expression e = arg.Expr;\r
 644                                         if (!(e is StringConstant)){\r
 645                                                 Error_AttributeConstructorMismatch (a.Location);\r
 646                                                 return null;\r
 647                                         }\r
 648 \r
 649                                         //\r
 650                                         // Remove the attribute from the list\r
 651                                         //\r
 652                                         asec.Attributes.Remove (a);\r
 653 \r
 654                                         return (((StringConstant) e).Value);\r
 655                                 }\r
 656                         }\r
 657                         return null;\r
 658                 }\r
 659 \r
 660                 //\r
 661                 // This pulls the condition name out of a Conditional attribute\r
 662                 //\r
 663                 public string Conditional_GetConditionName ()\r
 664                 {\r
 665                         //\r
 666                         // So we have a Conditional, pull the data out.\r
 667                         //\r
 668                         if (Arguments == null || Arguments [0] == null){\r
 669                                 Error_AttributeConstructorMismatch (Location);\r
 670                                 return null;\r
 671                         }\r
 672 \r
 673                         ArrayList pos_args = (ArrayList) Arguments [0];\r
 674                         if (pos_args.Count != 1){\r
 675                                 Error_AttributeConstructorMismatch (Location);\r
 676                                 return null;\r
 677                         }\r
 678 \r
 679                         Argument arg = (Argument) pos_args [0]; \r
 680                         if (!(arg.Expr is StringConstant)){\r
 681                                 Error_AttributeConstructorMismatch (Location);\r
 682                                 return null;\r
 683                         }\r
 684 \r
 685                         return ((StringConstant) arg.Expr).Value;\r
 686                 }\r
 687 \r
 688                 //\r
 689                 // This pulls the obsolete message and error flag out of an Obsolete attribute\r
 690                 //\r
 691                 public string Obsolete_GetObsoleteMessage (out bool is_error)\r
 692                 {\r
 693                         is_error = false;\r
 694                         //\r
 695                         // So we have an Obsolete, pull the data out.\r
 696                         //\r
 697                         if (Arguments == null || Arguments [0] == null)\r
 698                                 return "";\r
 699 \r
 700                         ArrayList pos_args = (ArrayList) Arguments [0];\r
 701                         if (pos_args.Count == 0)\r
 702                                 return "";\r
 703                         else if (pos_args.Count > 2){\r
 704                                 Error_AttributeConstructorMismatch (Location);\r
 705                                 return null;\r
 706                         }\r
 707 \r
 708                         Argument arg = (Argument) pos_args [0]; \r
 709                         if (!(arg.Expr is StringConstant)){\r
 710                                 Error_AttributeConstructorMismatch (Location);\r
 711                                 return null;\r
 712                         }\r
 713 \r
 714                         if (pos_args.Count == 2){\r
 715                                 Argument arg2 = (Argument) pos_args [1];\r
 716                                 if (!(arg2.Expr is BoolConstant)){\r
 717                                         Error_AttributeConstructorMismatch (Location);\r
 718                                         return null;\r
 719                                 }\r
 720                                 is_error = ((BoolConstant) arg2.Expr).Value;\r
 721                         }\r
 722 \r
 723                         return ((StringConstant) arg.Expr).Value;\r
 724                 }\r
 725 \r
 726                 //\r
 727                 // Applies the attributes to the `builder'.\r
 728                 //\r
 729                 public static void ApplyAttributes (EmitContext ec, object builder, object kind,\r
 730                                                     Attributes opt_attrs)\r
 731                 {\r
 732                         Type attr_type = null;\r
 733                         \r
 734                         if (opt_attrs == null)\r
 735                                 return;\r
 736                         if (opt_attrs.AttributeSections == null)\r
 737                                 return;\r
 738 \r
 739                         ArrayList emitted_attrs = new ArrayList ();\r
 740                         ArrayList emitted_targets = new ArrayList ();\r
 741 \r
 742                         foreach (AttributeSection asec in opt_attrs.AttributeSections) {\r
 743                                 string attr_target = asec.Target;\r
 744                                 \r
 745                                 if (asec.Attributes == null)\r
 746                                         continue;\r
 747 \r
 748                                 if (attr_target == "assembly" && !(builder is AssemblyBuilder))\r
 749                                         continue;\r
 750 \r
 751                                 if (attr_target == "return" && !(builder is ParameterBuilder))\r
 752                                         continue;\r
 753                                 \r
 754                                 foreach (Attribute a in asec.Attributes) {\r
 755                                         Location loc = a.Location;\r
 756                                         CustomAttributeBuilder cb = a.Resolve (ec);\r
 757                                         attr_type = a.Type;\r
 758 \r
 759                                         if (cb == null) \r
 760                                                 continue;\r
 761                                         \r
 762                                         if (!(kind is TypeContainer))\r
 763                                                 if (!CheckAttribute (a, kind)) {\r
 764                                                         Error_AttributeNotValidForElement (a, loc);\r
 765                                                         return;\r
 766                                                 }\r
 767 \r
 768                                         //\r
 769                                         // Perform the check for duplicate attributes\r
 770                                         //\r
 771                                         if (emitted_attrs.Contains (attr_type) &&\r
 772                                             emitted_targets.Contains (attr_target) &&\r
 773                                             !TypeManager.AreMultipleAllowed (attr_type)) {\r
 774                                                 Report.Error (579, loc, "Duplicate '" + a.Name + "' attribute");\r
 775                                                 return;\r
 776                                         }\r
 777 \r
 778                                         if (kind is Method || kind is Operator || kind is InterfaceMethod ||\r
 779                                             kind is Accessor) {\r
 780                                                 if (attr_type == TypeManager.methodimpl_attr_type) {\r
 781                                                         if (a.ImplOptions == MethodImplOptions.InternalCall)\r
 782                                                                 ((MethodBuilder) builder).\r
 783                                                                 SetImplementationFlags (\r
 784                                                                         MethodImplAttributes.InternalCall |\r
 785                                                                         MethodImplAttributes.Runtime);\r
 786                                                         else\r
 787                                                                 ((MethodBuilder) builder).SetCustomAttribute (cb);\r
 788                                                 } else if (attr_type != TypeManager.dllimport_type){\r
 789                                                         ((MethodBuilder) builder).SetCustomAttribute (cb);\r
 790                                                 }\r
 791                                         } else if (kind is Constructor) {\r
 792                                                 ((ConstructorBuilder) builder).SetCustomAttribute (cb);\r
 793                                         } else if (kind is Field) {\r
 794                                                 ((FieldBuilder) builder).SetCustomAttribute (cb);\r
 795                                         } else if (kind is Property || kind is Indexer ||\r
 796                                                    kind is InterfaceProperty || kind is InterfaceIndexer) {\r
 797                                                 ((PropertyBuilder) builder).SetCustomAttribute (cb);\r
 798                                         } else if (kind is Event || kind is InterfaceEvent) {\r
 799                                                 ((MyEventBuilder) builder).SetCustomAttribute (cb);\r
 800                                         } else if (kind is ParameterBuilder) {\r
 801 \r
 802                                                 if (attr_type == TypeManager.marshal_as_attr_type) {\r
 803                                                         UnmanagedMarshal marshal =\r
 804                                                                 UnmanagedMarshal.DefineUnmanagedMarshal (a.UnmanagedType);\r
 805                                                         \r
 806                                                         ((ParameterBuilder) builder).SetMarshal (marshal);\r
 807                                                 } else { \r
 808 \r
 809                                                         try {\r
 810                                                                 ((ParameterBuilder) builder).SetCustomAttribute (cb);\r
 811                                                         } catch (System.ArgumentException) {\r
 812                                                                 Report.Warning (-24, loc,\r
 813                                                                                 "The Microsoft Runtime cannot set attributes \n" +\r
 814                                                                                 "on the return type of a method. Please use the \n" +\r
 815                                                                                 "Mono runtime instead.");\r
 816                                                         }\r
 817 \r
 818                                                 }\r
 819                                         } else if (kind is Enum) {\r
 820                                                 ((TypeBuilder) builder).SetCustomAttribute (cb); \r
 821 \r
 822                                         } else if (kind is TypeContainer) {\r
 823                                                 TypeContainer tc = (TypeContainer) kind;\r
 824                                                 \r
 825                                                 if (a.UsageAttr) {\r
 826                                                         tc.Targets = a.Targets;\r
 827                                                         tc.AllowMultiple = a.AllowMultiple;\r
 828                                                         tc.Inherited = a.Inherited;\r
 829 \r
 830                                                         TypeManager.RegisterAttributeAllowMultiple (tc.TypeBuilder,\r
 831                                                                                                     tc.AllowMultiple);\r
 832                                                         \r
 833                                                 } else if (attr_type == TypeManager.default_member_type) {\r
 834                                                         if (tc.Indexers != null) {\r
 835                                                                 Report.Error (646, loc,\r
 836                                                                       "Cannot specify the DefaultMember attribute on" +\r
 837                                                                       " a type containing an indexer");\r
 838                                                                 return;\r
 839                                                         }\r
 840 \r
 841                                                 } else {\r
 842                                                         if (!CheckAttribute (a, kind)) {\r
 843                                                                 Error_AttributeNotValidForElement (a, loc);\r
 844                                                                 return;\r
 845                                                         }\r
 846                                                 }\r
 847 \r
 848                                                 try {\r
 849                                                         ((TypeBuilder) builder).SetCustomAttribute (cb);\r
 850                                                 } catch (System.ArgumentException) {\r
 851                                                         Report.Warning (\r
 852                                                                 -21, loc,\r
 853                                                 "The CharSet named property on StructLayout\n"+\r
 854                                                 "\tdoes not work correctly on Microsoft.NET\n"+\r
 855                                                 "\tYou might want to remove the CharSet declaration\n"+\r
 856                                                 "\tor compile using the Mono runtime instead of the\n"+\r
 857                                                 "\tMicrosoft .NET runtime");\r
 858                                                 }\r
 859                                                 \r
 860                                         } else if (kind is Interface) {\r
 861                                                 Interface iface = (Interface) kind;\r
 862 \r
 863                                                 if ((attr_type == TypeManager.default_member_type) &&\r
 864                                                     (iface.InterfaceIndexers != null)) {\r
 865                                                         Report.Error (\r
 866                                                                 646, loc,\r
 867                                                                 "Cannot specify the DefaultMember attribute on" +\r
 868                                                                 " a type containing an indexer");\r
 869                                                         return;\r
 870                                                 }\r
 871 \r
 872                                                 if (!CheckAttribute (a, kind)) {\r
 873                                                         Error_AttributeNotValidForElement (a, loc);\r
 874                                                         return;\r
 875                                                 }\r
 876 \r
 877                                                 ((TypeBuilder) builder).SetCustomAttribute (cb);\r
 878                                         } else if (kind is AssemblyBuilder){\r
 879                                                 ((AssemblyBuilder) builder).SetCustomAttribute (cb);\r
 880                                         } else if (kind is ModuleBuilder) {\r
 881                                                 ((ModuleBuilder) builder).SetCustomAttribute (cb);\r
 882                                         } else if (kind is FieldBuilder) {\r
 883                                                 ((FieldBuilder) builder).SetCustomAttribute (cb);\r
 884                                         } else\r
 885                                                 throw new Exception ("Unknown kind: " + kind);\r
 886 \r
 887                                         //\r
 888                                         // Once an attribute type has been emitted once we\r
 889                                         // keep track of the info to prevent multiple occurences\r
 890                                         // for attributes which do not explicitly allow it\r
 891                                         //\r
 892                                         if (!emitted_attrs.Contains (attr_type))\r
 893                                                 emitted_attrs.Add (attr_type);\r
 894 \r
 895                                         //\r
 896                                         // We keep of this target-wise and so emitted targets\r
 897                                         // are tracked too\r
 898                                         //\r
 899                                         if (!emitted_targets.Contains (attr_target))\r
 900                                                 emitted_targets.Add (attr_target);\r
 901                                 }\r
 902                                 \r
 903                                 \r
 904                         }\r
 905                 }\r
 906 \r
 907                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,\r
 908                                                           MethodAttributes flags, Type ret_type, Type [] param_types)\r
 909                 {\r
 910                         //\r
 911                         // We extract from the attribute the information we need \r
 912                         //\r
 913 \r
 914                         if (Arguments == null) {\r
 915                                 Console.WriteLine ("Internal error : this is not supposed to happen !");\r
 916                                 return null;\r
 917                         }\r
 918 \r
 919                         Type = CheckAttributeType (ec);\r
 920                         if (Type == null)\r
 921                                 return null;\r
 922                         \r
 923                         ArrayList named_args = new ArrayList ();\r
 924                         \r
 925                         ArrayList pos_args = (ArrayList) Arguments [0];\r
 926                         if (Arguments.Count > 1)\r
 927                                 named_args = (ArrayList) Arguments [1];\r
 928                         \r
 929 \r
 930                         string dll_name = null;\r
 931                         \r
 932                         Argument tmp = (Argument) pos_args [0];\r
 933 \r
 934                         if (!tmp.Resolve (ec, Location))\r
 935                                 return null;\r
 936                         \r
 937                         if (tmp.Expr is Constant)\r
 938                                 dll_name = (string) ((Constant) tmp.Expr).GetValue ();\r
 939                         else { \r
 940                                 Error_AttributeArgumentNotValid (Location);\r
 941                                 return null;\r
 942                         }\r
 943 \r
 944                         // Now we process the named arguments\r
 945                         CallingConvention cc = CallingConvention.Winapi;\r
 946                         CharSet charset = CharSet.Ansi;\r
 947                         bool preserve_sig = true;\r
 948                         bool exact_spelling = false;\r
 949                         bool set_last_err = false;\r
 950                         string entry_point = null;\r
 951 \r
 952                         for (int i = 0; i < named_args.Count; i++) {\r
 953 \r
 954                                 DictionaryEntry de = (DictionaryEntry) named_args [i];\r
 955 \r
 956                                 string member_name = (string) de.Key;\r
 957                                 Argument a  = (Argument) de.Value;\r
 958 \r
 959                                 if (!a.Resolve (ec, Location))\r
 960                                         return null;\r
 961 \r
 962                                 Expression member = Expression.MemberLookup (\r
 963                                         ec, Type, member_name, \r
 964                                         MemberTypes.Field | MemberTypes.Property,\r
 965                                         BindingFlags.Public | BindingFlags.Instance,\r
 966                                         Location);\r
 967 \r
 968                                 if (member == null || !(member is FieldExpr)) {\r
 969                                         Error_InvalidNamedArgument (member_name);\r
 970                                         return null;\r
 971                                 }\r
 972 \r
 973                                 if (member is FieldExpr) {\r
 974                                         FieldExpr fe = (FieldExpr) member;\r
 975                                         FieldInfo fi = fe.FieldInfo;\r
 976 \r
 977                                         if (fi.IsInitOnly) {\r
 978                                                 Error_InvalidNamedArgument (member_name);\r
 979                                                 return null;\r
 980                                         }\r
 981 \r
 982                                         if (a.Expr is Constant) {\r
 983                                                 Constant c = (Constant) a.Expr;\r
 984                                                 \r
 985                                                 if (member_name == "CallingConvention")\r
 986                                                         cc = (CallingConvention) c.GetValue ();\r
 987                                                 else if (member_name == "CharSet")\r
 988                                                         charset = (CharSet) c.GetValue ();\r
 989                                                 else if (member_name == "EntryPoint")\r
 990                                                         entry_point = (string) c.GetValue ();\r
 991                                                 else if (member_name == "SetLastError")\r
 992                                                         set_last_err = (bool) c.GetValue ();\r
 993                                                 else if (member_name == "ExactSpelling")\r
 994                                                         exact_spelling = (bool) c.GetValue ();\r
 995                                                 else if (member_name == "PreserveSig")\r
 996                                                         preserve_sig = (bool) c.GetValue ();\r
 997                                         } else { \r
 998                                                 Error_AttributeArgumentNotValid (Location);\r
 999                                                 return null;\r
1000                                         }\r
1001                                         \r
1002                                 }\r
1003                         }\r
1004 \r
1005                         if (entry_point == null)\r
1006                                 entry_point = name;\r
1007                         \r
1008                         MethodBuilder mb = builder.DefinePInvokeMethod (\r
1009                                 name, dll_name, entry_point, flags | MethodAttributes.HideBySig,\r
1010                                 CallingConventions.Standard,\r
1011                                 ret_type,\r
1012                                 param_types,\r
1013                                 cc,\r
1014                                 charset);\r
1015 \r
1016                         if (preserve_sig)\r
1017                                 mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);\r
1018                         \r
1019                         return mb;\r
1020                 }\r
1021                 \r
1022         }\r
1023         \r
1024         public class AttributeSection {\r
1025                 public readonly string    Target;\r
1026                 public readonly ArrayList Attributes;\r
1027                 \r
1028                 public AttributeSection (string target, ArrayList attrs)\r
1029                 {\r
1030                         Target = target;\r
1031                         Attributes = attrs;\r
1032                 }\r
1033                 \r
1034         }\r
1035 \r
1036         public class Attributes {\r
1037                 public ArrayList AttributeSections;\r
1038 \r
1039                 public Attributes (AttributeSection a)\r
1040                 {\r
1041                         AttributeSections = new ArrayList ();\r
1042                         AttributeSections.Add (a);\r
1043 \r
1044                 }\r
1045 \r
1046                 public void AddAttributeSection (AttributeSection a)\r
1047                 {\r
1048                         if (a != null && !AttributeSections.Contains (a))\r
1049                                 AttributeSections.Add (a);\r
1050                 }\r
1051 \r
1052                 public bool Contains (Type t)\r
1053                 {\r
1054                         foreach (AttributeSection attr_section in AttributeSections){\r
1055                                 foreach (Attribute a in attr_section.Attributes){\r
1056                                         if (a.Type == t)\r
1057                                                 return true;\r
1058                                 }\r
1059                         }\r
1060                         return false;\r
1061                 }\r
1062         }\r
1063 }\r