mcs/gmcs/attribute.cs

   1 // -*- coding: dos -*-
   2 //\r
   3 // attribute.cs: Attribute Handler\r
   4 //\r
   5 // Author: Ravi Pratap (ravi@ximian.com)\r
   6 //\r
   7 // Licensed under the terms of the GNU GPL\r
   8 //\r
   9 // (C) 2001 Ximian, Inc (http://www.ximian.com)\r
  10 //\r
  11 //\r
  12 \r
  13 using System;\r
  14 using System.Diagnostics;\r
  15 using System.Collections;\r
  16 using System.Reflection;\r
  17 using System.Reflection.Emit;\r
  18 using System.Runtime.InteropServices;\r
  19 using System.Runtime.CompilerServices;\r
  20 using System.Text;\r
  21 \r
  22 namespace Mono.CSharp {\r
  23 \r
  24         public class Attribute {\r
  25                 public readonly string    Name;\r
  26                 public readonly ArrayList Arguments;\r
  27 \r
  28                 Location Location;\r
  29 \r
  30                 public Type Type;\r
  31                 \r
  32                 //\r
  33                 // The following are only meaningful when the attribute\r
  34                 // being emitted is an AttributeUsage attribute\r
  35                 //\r
  36                 AttributeTargets Targets;\r
  37                 bool AllowMultiple;\r
  38                 bool Inherited;\r
  39 \r
  40                 bool UsageAttr = false;\r
  41                 \r
  42                 MethodImplOptions ImplOptions;\r
  43                 UnmanagedType     UnmanagedType;\r
  44                 CustomAttributeBuilder cb;\r
  45         \r
  46                 // non-null if named args present after Resolve () is called\r
  47                 PropertyInfo [] prop_info_arr;\r
  48                 FieldInfo [] field_info_arr;\r
  49                 object [] field_values_arr;\r
  50                 object [] prop_values_arr;\r
  51                 \r
  52                 public Attribute (string name, ArrayList args, Location loc)\r
  53                 {\r
  54                         Name = name;\r
  55                         Arguments = args;\r
  56                         Location = loc;\r
  57                 }\r
  58 \r
  59                 void Error_InvalidNamedArgument (string name)\r
  60                 {\r
  61                         Report.Error (617, Location, "'" + name + "' is not a valid named attribute " +\r
  62                                       "argument. Named attribute arguments must be fields which are not " +\r
  63                                       "readonly, static or const, or properties with a set accessor which "+\r
  64                                       "are not static.");\r
  65                 }\r
  66 \r
  67                 static void Error_AttributeArgumentNotValid (Location loc)\r
  68                 {\r
  69                         Report.Error (182, loc,\r
  70                                       "An attribute argument must be a constant expression, typeof " +\r
  71                                       "expression or array creation expression");\r
  72                 }\r
  73 \r
  74                 static void Error_AttributeConstructorMismatch (Location loc)\r
  75                 {\r
  76                         Report.Error (-6, loc,\r
  77                                       "Could not find a constructor for this argument list.");\r
  78                 }\r
  79 \r
  80                 static void Error_TypeParameterInAttribute (Location loc)\r
  81                 {\r
  82                         Report.Error (\r
  83                                 -202, loc, "Can not use a type parameter in an attribute");\r
  84                 }\r
  85 \r
  86                 /// <summary>\r
  87                 ///   Tries to resolve the type of the attribute. Flags an error if it can't.\r
  88                 /// </summary>\r
  89                 private Type CheckAttributeType (EmitContext ec) {\r
  90                         Type t;\r
  91                         bool isattributeclass = true;\r
  92                         \r
  93                         t = RootContext.LookupType (ec.DeclSpace, Name, true, Location);\r
  94                         if (t != null) {\r
  95                                 isattributeclass = t.IsSubclassOf (TypeManager.attribute_type);\r
  96                                 if (isattributeclass)\r
  97                                         return t;\r
  98                         }\r
  99                         t = RootContext.LookupType (ec.DeclSpace, Name + "Attribute", true, Location);\r
 100                         if (t != null) {\r
 101                                 if (t.IsSubclassOf (TypeManager.attribute_type))\r
 102                                         return t;\r
 103                         }\r
 104                         if (!isattributeclass) {\r
 105                                 Report.Error (616, Location, "'" + Name + "': is not an attribute class");\r
 106                                 return null;\r
 107                         }\r
 108                         if (t != null) {\r
 109                                 Report.Error (616, Location, "'" + Name + "Attribute': is not an attribute class");\r
 110                                 return null;\r
 111                         }\r
 112                         Report.Error (\r
 113                                 246, Location, "Could not find attribute '" + Name + "' (are you" +\r
 114                                 " missing a using directive or an assembly reference ?)");\r
 115                         return null;\r
 116                 }\r
 117 \r
 118                 public Type ResolveType (EmitContext ec)\r
 119                 {\r
 120                         Type = CheckAttributeType (ec);\r
 121                         return Type;\r
 122                 }\r
 123 \r
 124                 /// <summary>\r
 125                 ///   Validates the guid string\r
 126                 /// </summary>\r
 127                 bool ValidateGuid (string guid)\r
 128                 {\r
 129                         try {\r
 130                                 new Guid (guid);\r
 131                                 return true;\r
 132                         } catch {\r
 133                                 Report.Error (647, Location, "Format of GUID is invalid: " + guid);\r
 134                                 return false;\r
 135                         }\r
 136                 }\r
 137 \r
 138                 //\r
 139                 // Given an expression, if the expression is a valid attribute-argument-expression\r
 140                 // returns an object that can be used to encode it, or null on failure.\r
 141                 //\r
 142                 public static bool GetAttributeArgumentExpression (Expression e, Location loc, out object result)\r
 143                 {\r
 144                         if (e is Constant) {\r
 145                                 result = ((Constant) e).GetValue ();\r
 146                                 return true;\r
 147                         } else if (e is TypeOf) {\r
 148                                 result = ((TypeOf) e).TypeArg;\r
 149                                 return true;\r
 150                         } else if (e is ArrayCreation){\r
 151                                 result =  ((ArrayCreation) e).EncodeAsAttribute ();\r
 152                                 if (result != null)\r
 153                                         return true;\r
 154                         } else if (e is EmptyCast) {\r
 155                                 result = e;\r
 156                                 if (((EmptyCast) e).Child is Constant) {\r
 157                                         result = ((Constant) ((EmptyCast)e).Child).GetValue();\r
 158                                 }\r
 159                                 return true;\r
 160                         }\r
 161 \r
 162                         result = null;\r
 163                         Error_AttributeArgumentNotValid (loc);\r
 164                         return false;\r
 165                 }\r
 166                 \r
 167                 public CustomAttributeBuilder Resolve (EmitContext ec)\r
 168                 {\r
 169                         if (Type == null)\r
 170                                 Type = CheckAttributeType (ec);\r
 171                         if (Type == null)\r
 172                                 return null;\r
 173 \r
 174                         bool MethodImplAttr = false;\r
 175                         bool MarshalAsAttr = false;\r
 176                         bool GuidAttr = false;\r
 177                         UsageAttr = false;\r
 178 \r
 179                         bool DoCompares = true;\r
 180 \r
 181                         //\r
 182                         // If we are a certain special attribute, we\r
 183                         // set the information accordingly\r
 184                         //\r
 185                         \r
 186                         if (Type == TypeManager.attribute_usage_type)\r
 187                                 UsageAttr = true;\r
 188                         else if (Type == TypeManager.methodimpl_attr_type)\r
 189                                 MethodImplAttr = true;\r
 190                         else if (Type == TypeManager.marshal_as_attr_type)\r
 191                                 MarshalAsAttr = true;\r
 192                         else if (Type == TypeManager.guid_attr_type)\r
 193                                 GuidAttr = true;\r
 194                         else\r
 195                                 DoCompares = false;\r
 196 \r
 197                         // Now we extract the positional and named arguments\r
 198                         \r
 199                         ArrayList pos_args = new ArrayList ();\r
 200                         ArrayList named_args = new ArrayList ();\r
 201                         int pos_arg_count = 0;\r
 202                         \r
 203                         if (Arguments != null) {\r
 204                                 pos_args = (ArrayList) Arguments [0];\r
 205                                 if (pos_args != null)\r
 206                                         pos_arg_count = pos_args.Count;\r
 207                                 if (Arguments.Count > 1)\r
 208                                         named_args = (ArrayList) Arguments [1];\r
 209                         }\r
 210 \r
 211                         object [] pos_values = new object [pos_arg_count];\r
 212 \r
 213                         //\r
 214                         // First process positional arguments \r
 215                         //\r
 216 \r
 217                         int i;\r
 218                         for (i = 0; i < pos_arg_count; i++) {\r
 219                                 Argument a = (Argument) pos_args [i];\r
 220                                 Expression e;\r
 221 \r
 222                                 if (!a.Resolve (ec, Location))\r
 223                                         return null;\r
 224 \r
 225                                 e = a.Expr;\r
 226 \r
 227                                 object val;\r
 228                                 if (!GetAttributeArgumentExpression (e, Location, out val))\r
 229                                         return null;\r
 230                                 \r
 231                                 pos_values [i] = val;\r
 232                                 if (DoCompares){\r
 233                                         if (UsageAttr)\r
 234                                                 this.Targets = (AttributeTargets) pos_values [0];\r
 235                                         else if (MethodImplAttr)\r
 236                                                 this.ImplOptions = (MethodImplOptions) pos_values [0];\r
 237                                         else if (GuidAttr){\r
 238                                                 //\r
 239                                                 // we will later check the validity of the type\r
 240                                                 //\r
 241                                                 if (pos_values [0] is string){\r
 242                                                         if (!ValidateGuid ((string) pos_values [0]))\r
 243                                                                 return null;\r
 244                                                 }\r
 245                                                 \r
 246                                         } else if (MarshalAsAttr)\r
 247                                                 this.UnmanagedType =\r
 248                                                 (System.Runtime.InteropServices.UnmanagedType) pos_values [0];\r
 249                                 }\r
 250                         }\r
 251 \r
 252                         //\r
 253                         // Now process named arguments\r
 254                         //\r
 255 \r
 256                         ArrayList field_infos = null;\r
 257                         ArrayList prop_infos  = null;\r
 258                         ArrayList field_values = null;\r
 259                         ArrayList prop_values = null;\r
 260 \r
 261                         if (named_args.Count > 0) {\r
 262                                 field_infos = new ArrayList ();\r
 263                                 prop_infos  = new ArrayList ();\r
 264                                 field_values = new ArrayList ();\r
 265                                 prop_values = new ArrayList ();\r
 266                         }\r
 267                         \r
 268                         for (i = 0; i < named_args.Count; i++) {\r
 269                                 DictionaryEntry de = (DictionaryEntry) named_args [i];\r
 270                                 string member_name = (string) de.Key;\r
 271                                 Argument a  = (Argument) de.Value;\r
 272                                 Expression e;\r
 273                                 \r
 274                                 if (!a.Resolve (ec, Location))\r
 275                                         return null;\r
 276 \r
 277                                 Expression member = Expression.MemberLookup (\r
 278                                         ec, Type, member_name,\r
 279                                         MemberTypes.Field | MemberTypes.Property,\r
 280                                         BindingFlags.Public | BindingFlags.Instance,\r
 281                                         Location);\r
 282 \r
 283                                 if (member == null || !(member is PropertyExpr || member is FieldExpr)) {\r
 284                                         Error_InvalidNamedArgument (member_name);\r
 285                                         return null;\r
 286                                 }\r
 287 \r
 288                                 e = a.Expr;\r
 289                                 if (e is TypeParameterExpr){\r
 290                                         Error_TypeParameterInAttribute (Location);\r
 291                                         return null;\r
 292                                 }\r
 293                                         \r
 294                                 if (member is PropertyExpr) {\r
 295                                         PropertyExpr pe = (PropertyExpr) member;\r
 296                                         PropertyInfo pi = pe.PropertyInfo;\r
 297 \r
 298                                         if (!pi.CanWrite) {\r
 299                                                 Error_InvalidNamedArgument (member_name);\r
 300                                                 return null;\r
 301                                         }\r
 302 \r
 303                                         if (e is Constant) {\r
 304                                                 object o = ((Constant) e).GetValue ();\r
 305                                                 prop_values.Add (o);\r
 306                                                 \r
 307                                                 if (UsageAttr) {\r
 308                                                         if (member_name == "AllowMultiple")\r
 309                                                                 this.AllowMultiple = (bool) o;\r
 310                                                         if (member_name == "Inherited")\r
 311                                                                 this.Inherited = (bool) o;\r
 312                                                 }\r
 313                                                 \r
 314                                         } else if (e is TypeOf) {\r
 315                                                 prop_values.Add (((TypeOf) e).TypeArg);\r
 316                                         } else if (e is ArrayCreation) {\r
 317                                                 prop_values.Add (((ArrayCreation) e).EncodeAsAttribute());\r
 318                                         } else {\r
 319                                                 Error_AttributeArgumentNotValid (Location);\r
 320                                                 return null;\r
 321                                         }\r
 322                                         \r
 323                                         prop_infos.Add (pi);\r
 324                                         \r
 325                                 } else if (member is FieldExpr) {\r
 326                                         FieldExpr fe = (FieldExpr) member;\r
 327                                         FieldInfo fi = fe.FieldInfo;\r
 328 \r
 329                                         if (fi.IsInitOnly) {\r
 330                                                 Error_InvalidNamedArgument (member_name);\r
 331                                                 return null;\r
 332                                         }\r
 333 \r
 334                                         //\r
 335                                         // Handle charset here, and set the TypeAttributes\r
 336                                         \r
 337                                         if (e is Constant){\r
 338                                                 object value = ((Constant) e).GetValue ();\r
 339                                                 \r
 340                                                 field_values.Add (value);\r
 341                                         } else if (e is TypeOf) {\r
 342                                                 field_values.Add (((TypeOf) e).TypeArg);\r
 343                                         } else {\r
 344                                                 Error_AttributeArgumentNotValid (Location);\r
 345                                                 return null;\r
 346                                         }\r
 347                                         \r
 348                                         field_infos.Add (fi);\r
 349                                 }\r
 350                         }\r
 351 \r
 352                         Expression mg = Expression.MemberLookup (\r
 353                                 ec, Type, ".ctor", MemberTypes.Constructor,\r
 354                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly,\r
 355                                 Location);\r
 356 \r
 357                         if (mg == null) {\r
 358                                 Error_AttributeConstructorMismatch (Location);\r
 359                                 return null;\r
 360                         }\r
 361 \r
 362                         MethodBase constructor = Invocation.OverloadResolve (\r
 363                                 ec, (MethodGroupExpr) mg, pos_args, false, Location);\r
 364 \r
 365                         if (constructor == null) {\r
 366                                 Error_AttributeConstructorMismatch (Location);\r
 367                                 return null;\r
 368                         }\r
 369 \r
 370                         //\r
 371                         // Now we perform some checks on the positional args as they\r
 372                         // cannot be null for a constructor which expects a parameter\r
 373                         // of type object\r
 374                         //\r
 375 \r
 376                         ParameterData pd = Invocation.GetParameterData (constructor);\r
 377 \r
 378                         int group_in_params_array = Int32.MaxValue;\r
 379                         int pc = pd.Count;\r
 380                         if (pc > 0 && pd.ParameterModifier (pc-1) == Parameter.Modifier.PARAMS)\r
 381                                 group_in_params_array = pc-1;\r
 382                         \r
 383                         for (int j = 0; j < pos_arg_count; ++j) {\r
 384                                 Argument a = (Argument) pos_args [j];\r
 385                                 \r
 386                                 if (a.Expr is NullLiteral && pd.ParameterType (j) == TypeManager.object_type) {\r
 387                                         Error_AttributeArgumentNotValid (Location);\r
 388                                         return null;\r
 389                                 }\r
 390 \r
 391                                 if (j < group_in_params_array)\r
 392                                         continue;\r
 393                                 \r
 394                                 if (j == group_in_params_array){\r
 395                                         object v = pos_values [j];\r
 396                                         int count = pos_arg_count - j;\r
 397 \r
 398                                         object [] array = new object [count];\r
 399                                         pos_values [j] = array;\r
 400                                         array [0] = v;\r
 401                                 } else {\r
 402                                         object [] array = (object []) pos_values [group_in_params_array];\r
 403 \r
 404                                         array [j - group_in_params_array] = pos_values [j];\r
 405                                 }\r
 406                         }\r
 407 \r
 408                         //\r
 409                         // Adjust the size of the pos_values if it had params\r
 410                         //\r
 411                         if (group_in_params_array != Int32.MaxValue){\r
 412                                 int argc = group_in_params_array+1;\r
 413                                 object [] new_pos_values = new object [argc];\r
 414 \r
 415                                 for (int p = 0; p < argc; p++)\r
 416                                         new_pos_values [p] = pos_values [p];\r
 417                                 pos_values = new_pos_values;\r
 418                         }\r
 419 \r
 420                         try {\r
 421                                 if (named_args.Count > 0) {\r
 422                                         prop_info_arr = new PropertyInfo [prop_infos.Count];\r
 423                                         field_info_arr = new FieldInfo [field_infos.Count];\r
 424                                         field_values_arr = new object [field_values.Count];\r
 425                                         prop_values_arr = new object [prop_values.Count];\r
 426 \r
 427                                         field_infos.CopyTo  (field_info_arr, 0);\r
 428                                         field_values.CopyTo (field_values_arr, 0);\r
 429 \r
 430                                         prop_values.CopyTo  (prop_values_arr, 0);\r
 431                                         prop_infos.CopyTo   (prop_info_arr, 0);\r
 432 \r
 433                                         cb = new CustomAttributeBuilder (\r
 434                                                 (ConstructorInfo) constructor, pos_values,\r
 435                                                 prop_info_arr, prop_values_arr,\r
 436                                                 field_info_arr, field_values_arr);\r
 437                                 }\r
 438                                 else\r
 439                                         cb = new CustomAttributeBuilder (\r
 440                                                 (ConstructorInfo) constructor, pos_values);\r
 441                         } catch (NullReferenceException) {\r
 442                                 // \r
 443                                 // Don't know what to do here\r
 444                                 //\r
 445                                 Report.Warning (\r
 446                                         -101, Location, "NullReferenceException while trying to create attribute." +\r
 447                                         "Something's wrong!");\r
 448                         } catch (Exception e) {\r
 449                                 //\r
 450                                 // Sample:\r
 451                                 // using System.ComponentModel;\r
 452                                 // [DefaultValue (CollectionChangeAction.Add)]\r
 453                                 // class X { static void Main () {} }\r
 454                                 //\r
 455                                 Report.Warning (\r
 456                                         -23, Location,\r
 457                                         "The compiler can not encode this attribute in .NET due to\n" +\r
 458                                         "\ta bug in the .NET runtime.  Try the Mono runtime.\nThe error was: " + e.Message);\r
 459                         }\r
 460                         \r
 461                         return cb;\r
 462                 }\r
 463 \r
 464                 /// <summary>\r
 465                 ///   Get a string containing a list of valid targets for the attribute 'attr'\r
 466                 /// </summary>\r
 467                 static string GetValidTargets (Attribute attr)\r
 468                 {\r
 469                         StringBuilder sb = new StringBuilder ();\r
 470                         AttributeTargets targets = 0;\r
 471                         \r
 472                         TypeContainer a = TypeManager.LookupAttr (attr.Type);\r
 473 \r
 474                         if (a == null) {\r
 475                                 \r
 476                                 System.Attribute [] attrs = null;\r
 477                                 \r
 478                                 try {\r
 479                                         attrs = System.Attribute.GetCustomAttributes (attr.Type);\r
 480                                         \r
 481                                 } catch {\r
 482                                         Report.Error (-20, attr.Location, "Cannot find attribute type " + attr.Name +\r
 483                                                       " (maybe you forgot to set the usage using the" +\r
 484                                                       " AttributeUsage attribute ?).");\r
 485                                         return null;\r
 486                                 }\r
 487                                         \r
 488                                 foreach (System.Attribute tmp in attrs)\r
 489                                         if (tmp is AttributeUsageAttribute) {\r
 490                                                 targets = ((AttributeUsageAttribute) tmp).ValidOn;\r
 491                                                 break;\r
 492                                         }\r
 493                         } else\r
 494                                 targets = a.Targets;\r
 495 \r
 496                         \r
 497                         if ((targets & AttributeTargets.Assembly) != 0)\r
 498                                 sb.Append ("'assembly' ");\r
 499 \r
 500                         if ((targets & AttributeTargets.Class) != 0)\r
 501                                 sb.Append ("'class' ");\r
 502 \r
 503                         if ((targets & AttributeTargets.Constructor) != 0)\r
 504                                 sb.Append ("'constructor' ");\r
 505 \r
 506                         if ((targets & AttributeTargets.Delegate) != 0)\r
 507                                 sb.Append ("'delegate' ");\r
 508 \r
 509                         if ((targets & AttributeTargets.Enum) != 0)\r
 510                                 sb.Append ("'enum' ");\r
 511 \r
 512                         if ((targets & AttributeTargets.Event) != 0)\r
 513                                 sb.Append ("'event' ");\r
 514 \r
 515                         if ((targets & AttributeTargets.Field) != 0)\r
 516                                 sb.Append ("'field' ");\r
 517 \r
 518                         if ((targets & AttributeTargets.Interface) != 0)\r
 519                                 sb.Append ("'interface' ");\r
 520 \r
 521                         if ((targets & AttributeTargets.Method) != 0)\r
 522                                 sb.Append ("'method' ");\r
 523 \r
 524                         if ((targets & AttributeTargets.Module) != 0)\r
 525                                 sb.Append ("'module' ");\r
 526 \r
 527                         if ((targets & AttributeTargets.Parameter) != 0)\r
 528                                 sb.Append ("'parameter' ");\r
 529 \r
 530                         if ((targets & AttributeTargets.Property) != 0)\r
 531                                 sb.Append ("'property' ");\r
 532 \r
 533                         if ((targets & AttributeTargets.ReturnValue) != 0)\r
 534                                 sb.Append ("'return value' ");\r
 535 \r
 536                         if ((targets & AttributeTargets.Struct) != 0)\r
 537                                 sb.Append ("'struct' ");\r
 538 \r
 539                         return sb.ToString ();\r
 540 \r
 541                 }\r
 542 \r
 543                 public static void Error_AttributeNotValidForElement (Attribute a, Location loc)\r
 544                 {\r
 545                         Report.Error (\r
 546                                 592, loc, "Attribute '" + a.Name +\r
 547                                 "' is not valid on this declaration type. " +\r
 548                                 "It is valid on " + GetValidTargets (a) + "declarations only.");\r
 549                 }\r
 550 \r
 551                 /// <summary>\r
 552                 ///   Ensure that Attribute 'a' is being applied to the right language element (target)\r
 553                 /// </summary>\r
 554                 public static bool CheckAttributeTarget (Attribute a, object element)\r
 555                 {\r
 556                         TypeContainer attr = TypeManager.LookupAttr (a.Type);\r
 557                         AttributeTargets targets = 0;\r
 558 \r
 559                         if (attr == null) {\r
 560                                 System.Attribute [] attrs = null;\r
 561                                 \r
 562                                 try {\r
 563                                         attrs = System.Attribute.GetCustomAttributes (a.Type);\r
 564 \r
 565                                 } catch {\r
 566                                         Report.Error (-20, a.Location, "Cannot find attribute type " + a.Name +\r
 567                                                       " (maybe you forgot to set the usage using the" +\r
 568                                                       " AttributeUsage attribute ?).");\r
 569                                         return false;\r
 570                                 }\r
 571                                         \r
 572                                 foreach (System.Attribute tmp in attrs)\r
 573                                         if (tmp is AttributeUsageAttribute) { \r
 574                                                 targets = ((AttributeUsageAttribute) tmp).ValidOn;\r
 575                                                 break;\r
 576                                         }\r
 577                         } else\r
 578                                 targets = attr.Targets;\r
 579 \r
 580 \r
 581                         if (element is Class) {\r
 582                                 if ((targets & AttributeTargets.Class) != 0)\r
 583                                         return true;\r
 584                                 else\r
 585                                         return false;\r
 586                                 \r
 587                         } else if (element is Struct) {\r
 588                                 if ((targets & AttributeTargets.Struct) != 0)\r
 589                                         return true;\r
 590                                 else\r
 591                                         return false;\r
 592                         } else if (element is Constructor) {\r
 593                                 if ((targets & AttributeTargets.Constructor) != 0)\r
 594                                         return true;\r
 595                                 else\r
 596                                         return false;\r
 597                         } else if (element is Delegate) {\r
 598                                 if ((targets & AttributeTargets.Delegate) != 0)\r
 599                                         return true;\r
 600                                 else\r
 601                                         return false;\r
 602                         } else if (element is Enum) {\r
 603                                 if ((targets & AttributeTargets.Enum) != 0)\r
 604                                         return true;\r
 605                                 else\r
 606                                         return false;\r
 607                         } else if (element is Event) {\r
 608                                 if ((targets & AttributeTargets.Event) != 0)\r
 609                                         return true;\r
 610                                 else\r
 611                                         return false;\r
 612                         } else if (element is Field || element is FieldBuilder) {\r
 613                                 if ((targets & AttributeTargets.Field) != 0)\r
 614                                         return true;\r
 615                                 else\r
 616                                         return false;\r
 617                         } else if (element is Interface) {\r
 618                                 if ((targets & AttributeTargets.Interface) != 0)\r
 619                                         return true;\r
 620                                 else\r
 621                                         return false;\r
 622                         } else if (element is Method || element is Operator ||\r
 623                                    element is Accessor) {\r
 624                                 if ((targets & AttributeTargets.Method) != 0)\r
 625                                         return true;\r
 626                                 else\r
 627                                         return false;\r
 628                         } else if (element is ParameterBuilder) {\r
 629                                 if ((targets & AttributeTargets.Parameter) != 0 ||\r
 630                                     (targets & AttributeTargets.ReturnValue) != 0)\r
 631                                         return true;\r
 632                                 else\r
 633                                         return false;\r
 634                         } else if (element is Property || element is Indexer ||\r
 635                                    element is Accessor) {
 636                                 if ((targets & AttributeTargets.Property) != 0)\r
 637                                         return true;\r
 638                                 else\r
 639                                         return false;\r
 640                         } else if (element is AssemblyClass){
 641                                 if ((targets & AttributeTargets.Assembly) != 0)\r
 642                                         return true;\r
 643                                 else\r
 644                                         return false;\r
 645                         } else if (element is ModuleClass){
 646                                 if ((targets & AttributeTargets.Module) != 0)
 647                                         return true;
 648                                 else
 649                                         return false;
 650                         }\r
 651 \r
 652                         return false;\r
 653                 }\r
 654 \r
 655                 //\r
 656                 // This method should be invoked to pull the IndexerName attribute from an\r
 657                 // Indexer if it exists.\r
 658                 //\r
 659                 public static string ScanForIndexerName (EmitContext ec, Attributes opt_attrs)\r
 660                 {\r
 661                         if (opt_attrs == null)\r
 662                                 return null;\r
 663                         if (opt_attrs.AttributeSections == null)\r
 664                                 return null;\r
 665 \r
 666                         foreach (AttributeSection asec in opt_attrs.AttributeSections) {\r
 667                                 if (asec.Attributes == null)\r
 668                                         continue;\r
 669 \r
 670                                 foreach (Attribute a in asec.Attributes){\r
 671                                         if (a.ResolveType (ec) == null)\r
 672                                                 return null;\r
 673 \r
 674                                         if (a.Type != TypeManager.indexer_name_type)\r
 675                                                 continue;\r
 676 \r
 677                                         //\r
 678                                         // So we have found an IndexerName, pull the data out.\r
 679                                         //\r
 680                                         if (a.Arguments == null || a.Arguments [0] == null){\r
 681                                                 Error_AttributeConstructorMismatch (a.Location);\r
 682                                                 return null;\r
 683                                         }\r
 684                                         ArrayList pos_args = (ArrayList) a.Arguments [0];\r
 685                                         if (pos_args.Count == 0){\r
 686                                                 Error_AttributeConstructorMismatch (a.Location);\r
 687                                                 return null;\r
 688                                         }\r
 689                                         \r
 690                                         Argument arg = (Argument) pos_args [0];\r
 691                                         if (!arg.Resolve (ec, a.Location))\r
 692                                                 return null;\r
 693                                         \r
 694                                         Expression e = arg.Expr;\r
 695                                         if (!(e is StringConstant)){\r
 696                                                 Error_AttributeConstructorMismatch (a.Location);\r
 697                                                 return null;\r
 698                                         }\r
 699 \r
 700                                         //\r
 701                                         // Remove the attribute from the list\r
 702                                         //\r
 703                                         asec.Attributes.Remove (a);\r
 704 \r
 705                                         return (((StringConstant) e).Value);\r
 706                                 }\r
 707                         }\r
 708                         return null;\r
 709                 }\r
 710 \r
 711                 //\r
 712                 // This pulls the condition name out of a Conditional attribute\r
 713                 //\r
 714                 public string Conditional_GetConditionName ()\r
 715                 {\r
 716                         //\r
 717                         // So we have a Conditional, pull the data out.\r
 718                         //\r
 719                         if (Arguments == null || Arguments [0] == null){\r
 720                                 Error_AttributeConstructorMismatch (Location);\r
 721                                 return null;\r
 722                         }\r
 723 \r
 724                         ArrayList pos_args = (ArrayList) Arguments [0];\r
 725                         if (pos_args.Count != 1){\r
 726                                 Error_AttributeConstructorMismatch (Location);\r
 727                                 return null;\r
 728                         }\r
 729 \r
 730                         Argument arg = (Argument) pos_args [0]; \r
 731                         if (!(arg.Expr is StringConstant)){\r
 732                                 Error_AttributeConstructorMismatch (Location);\r
 733                                 return null;\r
 734                         }\r
 735 \r
 736                         return ((StringConstant) arg.Expr).Value;\r
 737                 }\r
 738 \r
 739                 //\r
 740                 // This pulls the obsolete message and error flag out of an Obsolete attribute\r
 741                 //\r
 742                 public string Obsolete_GetObsoleteMessage (out bool is_error)\r
 743                 {\r
 744                         is_error = false;\r
 745                         //\r
 746                         // So we have an Obsolete, pull the data out.\r
 747                         //\r
 748                         if (Arguments == null || Arguments [0] == null)\r
 749                                 return "";\r
 750 \r
 751                         ArrayList pos_args = (ArrayList) Arguments [0];\r
 752                         if (pos_args.Count == 0)\r
 753                                 return "";\r
 754                         else if (pos_args.Count > 2){\r
 755                                 Error_AttributeConstructorMismatch (Location);\r
 756                                 return null;\r
 757                         }\r
 758 \r
 759                         Argument arg = (Argument) pos_args [0]; \r
 760                         if (!(arg.Expr is StringConstant)){\r
 761                                 Error_AttributeConstructorMismatch (Location);\r
 762                                 return null;\r
 763                         }\r
 764 \r
 765                         if (pos_args.Count == 2){\r
 766                                 Argument arg2 = (Argument) pos_args [1];\r
 767                                 if (!(arg2.Expr is BoolConstant)){\r
 768                                         Error_AttributeConstructorMismatch (Location);\r
 769                                         return null;\r
 770                                 }\r
 771                                 is_error = ((BoolConstant) arg2.Expr).Value;\r
 772                         }\r
 773 \r
 774                         return ((StringConstant) arg.Expr).Value;\r
 775                 }\r
 776 \r
 777                 static object GetFieldValue (Attribute a, string name)\r
 778                 {\r
 779                         int i;\r
 780                         if (a.field_info_arr == null)\r
 781                                 return null;\r
 782                         i = 0;\r
 783                         foreach (FieldInfo fi in a.field_info_arr) {\r
 784                                 if (fi.Name == name)\r
 785                                         return a.field_values_arr [i];\r
 786                                 i++;\r
 787                         }\r
 788                         return null;\r
 789                 }\r
 790 \r
 791                 static UnmanagedMarshal GetMarshal (Attribute a)\r
 792                 {\r
 793                         object o = GetFieldValue (a, "ArraySubType");\r
 794                         UnmanagedType array_sub_type = o == null ? UnmanagedType.I4 : (UnmanagedType) o;\r
 795                         switch (a.UnmanagedType) {\r
 796                         case UnmanagedType.CustomMarshaler:\r
 797                                 MethodInfo define_custom = typeof (UnmanagedMarshal).GetMethod ("DefineCustom",\r
 798                                                                        BindingFlags.Static | BindingFlags.Public);\r
 799                                 if (define_custom == null)\r
 800                                         return null;\r
 801 \r
 802                                 object [] args = new object [4];\r
 803                                 args [0] = GetFieldValue (a, "MarshalTypeRef");\r
 804                                 args [1] = GetFieldValue (a, "MarshalCookie");\r
 805                                 args [2] = GetFieldValue (a, "MarshalType");\r
 806                                 args [3] = Guid.Empty;\r
 807                                 return (UnmanagedMarshal) define_custom.Invoke (null, args);\r
 808 \r
 809                         case UnmanagedType.LPArray:                             \r
 810                                 return UnmanagedMarshal.DefineLPArray (array_sub_type);\r
 811 \r
 812                         case UnmanagedType.SafeArray:\r
 813                                 return UnmanagedMarshal.DefineSafeArray (array_sub_type);\r
 814 \r
 815                         case UnmanagedType.ByValArray:\r
 816                                 return UnmanagedMarshal.DefineByValArray ((int) GetFieldValue (a, "SizeConst"));\r
 817 \r
 818                         case UnmanagedType.ByValTStr:\r
 819                                 return UnmanagedMarshal.DefineByValTStr ((int) GetFieldValue (a, "SizeConst"));\r
 820 \r
 821                         default:\r
 822                                 return UnmanagedMarshal.DefineUnmanagedMarshal (a.UnmanagedType);\r
 823                         }\r
 824                 }\r
 825 \r
 826                 /// <summary>\r
 827                 ///   Applies the attributes specified on target 'kind' to the `builder'.\r
 828                 /// </summary>\r
 829                 public static void ApplyAttributes (EmitContext ec, object builder, object kind,\r
 830                                                     Attributes opt_attrs)\r
 831                 {\r
 832                         Type attr_type = null;\r
 833                         \r
 834                         if (opt_attrs == null)\r
 835                                 return;\r
 836                         if (opt_attrs.AttributeSections == null)\r
 837                                 return;\r
 838 \r
 839                         ArrayList emitted_attrs = new ArrayList ();\r
 840                         ArrayList emitted_targets = new ArrayList ();\r
 841 \r
 842                         foreach (AttributeSection asec in opt_attrs.AttributeSections) {\r
 843                                 string attr_target = asec.Target;\r
 844                                 \r
 845                                 if (asec.Attributes == null)\r
 846                                         continue;\r
 847 \r
 848                                 if (attr_target == "return" && !(builder is ParameterBuilder))\r
 849                                         continue;\r
 850                                 \r
 851                                 foreach (Attribute a in asec.Attributes) {\r
 852                                         Location loc = a.Location;\r
 853                                         CustomAttributeBuilder cb = a.Resolve (ec);\r
 854                                         attr_type = a.Type;\r
 855 \r
 856                                         if (cb == null) \r
 857                                                 continue;\r
 858                                         \r
 859                                         if (!(kind is TypeContainer))\r
 860                                                 if (!CheckAttributeTarget (a, kind)) {\r
 861                                                         Error_AttributeNotValidForElement (a, loc);\r
 862                                                         return;\r
 863                                                 }\r
 864 \r
 865                                         //\r
 866                                         // Perform the check for duplicate attributes\r
 867                                         //\r
 868                                         if (emitted_attrs.Contains (attr_type) &&\r
 869                                             emitted_targets.Contains (attr_target) &&\r
 870                                             !TypeManager.AreMultipleAllowed (attr_type)) {\r
 871                                                 Report.Error (579, loc, "Duplicate '" + a.Name + "' attribute");\r
 872                                                 return;\r
 873                                         }\r
 874 \r
 875                                         if (kind is IAttributeSupport) {
 876                                                 if (attr_type == TypeManager.methodimpl_attr_type && a.ImplOptions == MethodImplOptions.InternalCall) {
 877                                                         ((MethodBuilder) builder).SetImplementationFlags (MethodImplAttributes.InternalCall | MethodImplAttributes.Runtime);
 878                                                 }
 879                                                 else {
 880                                                         IAttributeSupport attributeSupport = kind as IAttributeSupport;
 881                                                         attributeSupport.SetCustomAttribute (cb);
 882                                                 }
 883                                         }
 884                                         else if (kind is Method || kind is Operator || kind is Accessor) {\r
 885                                                 if (attr_type == TypeManager.methodimpl_attr_type) {\r
 886                                                         if (a.ImplOptions == MethodImplOptions.InternalCall)\r
 887                                                                 ((MethodBuilder) builder).\r
 888                                                                 SetImplementationFlags (\r
 889                                                                         MethodImplAttributes.InternalCall |\r
 890                                                                         MethodImplAttributes.Runtime);\r
 891                                                         else\r
 892                                                                 ((MethodBuilder) builder).SetCustomAttribute (cb);\r
 893                                                 } else if (attr_type != TypeManager.dllimport_type){\r
 894                                                         ((MethodBuilder) builder).SetCustomAttribute (cb);\r
 895                                                 }\r
 896                                         } else if (kind is Constructor) {\r
 897                                                 ((ConstructorBuilder) builder).SetCustomAttribute (cb);\r
 898                                         } else if (kind is Field) {\r
 899                                                 if (attr_type == TypeManager.marshal_as_attr_type) {\r
 900                                                         UnmanagedMarshal marshal = GetMarshal (a);\r
 901                                                         if (marshal == null) {\r
 902                                                                 Report.Warning (-24, loc,\r
 903                                                                         "The Microsoft Runtime cannot set this marshal info. " +\r
 904                                                                         "Please use the Mono runtime instead.");\r
 905                                                         } else {\r
 906                                                                 ((FieldBuilder) builder).SetMarshal (marshal);\r
 907                                                         }\r
 908                                                 } else { \r
 909                                                         ((FieldBuilder) builder).SetCustomAttribute (cb);\r
 910                                                 }\r
 911                                         } else if (kind is Property || kind is Indexer) {\r
 912
 913                                                 if (builder is PropertyBuilder)
 914                                                 ((PropertyBuilder) builder).SetCustomAttribute (cb);\r
 915                                                 //
 916                                                 // This is for the case we are setting attributes on
 917                                                 // the get and set accessors
 918                                                 //
 919                                                 else if (builder is MethodBuilder)
 920                                                         ((MethodBuilder) builder).SetCustomAttribute (cb);
 921                                         } else if (kind is Event) {\r
 922                                                 ((MyEventBuilder) builder).SetCustomAttribute (cb);\r
 923                                         } else if (kind is ParameterBuilder) {\r
 924 \r
 925                                                 if (attr_type == TypeManager.marshal_as_attr_type) {\r
 926                                                         UnmanagedMarshal marshal = GetMarshal (a);\r
 927                                                         if (marshal == null) {\r
 928                                                                 Report.Warning (-24, loc,\r
 929                                                                         "The Microsoft Runtime cannot set this marshal info. " +\r
 930                                                                         "Please use the Mono runtime instead.");\r
 931                                                         } else {\r
 932                                                                 ((ParameterBuilder) builder).SetMarshal (marshal);\r
 933                                                         }\r
 934                                                 } else { \r
 935 \r
 936                                                         try {\r
 937                                                                 ((ParameterBuilder) builder).SetCustomAttribute (cb);\r
 938                                                         } catch (System.ArgumentException) {\r
 939                                                                 Report.Warning (-24, loc,\r
 940                                                                                 "The Microsoft Runtime cannot set attributes \n" +\r
 941                                                                                 "on the return type of a method. Please use the \n" +\r
 942                                                                                 "Mono runtime instead.");\r
 943                                                         }\r
 944 \r
 945                                                 }\r
 946                                         } else if (kind is Enum) {\r
 947                                                 ((TypeBuilder) builder).SetCustomAttribute (cb); \r
 948 \r
 949                                         } else if (kind is TypeContainer) {\r
 950                                                 TypeContainer tc = (TypeContainer) kind;\r
 951                                                 \r
 952                                                 if (a.UsageAttr) {\r
 953                                                         tc.Targets = a.Targets;\r
 954                                                         tc.AllowMultiple = a.AllowMultiple;\r
 955                                                         tc.Inherited = a.Inherited;\r
 956 \r
 957                                                         TypeManager.RegisterAttributeAllowMultiple (tc.TypeBuilder,\r
 958                                                                                                     tc.AllowMultiple);\r
 959                                                         \r
 960                                                 } else if (attr_type == TypeManager.default_member_type) {\r
 961                                                         if (tc.Indexers != null) {\r
 962                                                                 Report.Error (646, loc,\r
 963                                                                       "Cannot specify the DefaultMember attribute on" +\r
 964                                                                       " a type containing an indexer");\r
 965                                                                 return;\r
 966                                                         }\r
 967 \r
 968                                                 } else {\r
 969                                                         if (!CheckAttributeTarget (a, kind)) {\r
 970                                                                 Error_AttributeNotValidForElement (a, loc);\r
 971                                                                 return;\r
 972                                                         }\r
 973                                                 }\r
 974 \r
 975                                                 try {\r
 976                                                         ((TypeBuilder) builder).SetCustomAttribute (cb);\r
 977                                                 } catch (System.ArgumentException) {\r
 978                                                         Report.Warning (\r
 979                                                                 -21, loc,\r
 980                                                 "The CharSet named property on StructLayout\n"+\r
 981                                                 "\tdoes not work correctly on Microsoft.NET\n"+\r
 982                                                 "\tYou might want to remove the CharSet declaration\n"+\r
 983                                                 "\tor compile using the Mono runtime instead of the\n"+\r
 984                                                 "\tMicrosoft .NET runtime");\r
 985                                                 }\r
 986                                         } else if (kind is Delegate){\r
 987                                                 if (!CheckAttributeTarget (a, kind)) {\r
 988                                                         Error_AttributeNotValidForElement (a, loc);\r
 989                                                         return;\r
 990                                                 }\r
 991                                                 try {\r
 992                                                         ((TypeBuilder) builder).SetCustomAttribute (cb);\r
 993                                                 } catch (System.ArgumentException) {\r
 994                                                         Report.Warning (\r
 995                                                                 -21, loc,\r
 996                                                 "The CharSet named property on StructLayout\n"+\r
 997                                                 "\tdoes not work correctly on Microsoft.NET\n"+\r
 998                                                 "\tYou might want to remove the CharSet declaration\n"+\r
 999                                                 "\tor compile using the Mono runtime instead of the\n"+\r
1000                                                 "\tMicrosoft .NET runtime");\r
1001                                                 }\r
1002                                         } else if (kind is Interface) {\r
1003                                                 Interface iface = (Interface) kind;\r
1004 \r
1005                                                 if ((attr_type == TypeManager.default_member_type) &&\r
1006                                                     (iface.Indexers != null)) {\r
1007                                                         Report.Error (\r
1008                                                                 646, loc,\r
1009                                                                 "Cannot specify the DefaultMember attribute on" +\r
1010                                                                 " a type containing an indexer");\r
1011                                                         return;\r
1012                                                 }\r
1013 \r
1014                                                 if (!CheckAttributeTarget (a, kind)) {\r
1015                                                         Error_AttributeNotValidForElement (a, loc);\r
1016                                                         return;\r
1017                                                 }\r
1018 \r
1019                                                 ((TypeBuilder) builder).SetCustomAttribute (cb);\r
1020                                         } else if (kind is AssemblyBuilder){\r
1021                                                 ((AssemblyBuilder) builder).SetCustomAttribute (cb);\r
1022                                         } else if (kind is ModuleBuilder) {\r
1023                                                 ((ModuleBuilder) builder).SetCustomAttribute (cb);\r
1024                                         } else if (kind is FieldBuilder) {\r
1025                                                 if (attr_type == TypeManager.marshal_as_attr_type) {\r
1026                                                         UnmanagedMarshal marshal = GetMarshal (a);\r
1027                                                         if (marshal == null) {\r
1028                                                                 Report.Warning (-24, loc,\r
1029                                                                         "The Microsoft Runtime cannot set this marshal info. " +\r
1030                                                                         "Please use the Mono runtime instead.");\r
1031                                                         } else {\r
1032                                                                 ((ParameterBuilder) builder).SetMarshal (marshal);\r
1033                                                         }\r
1034                                                 } else { \r
1035                                                         ((FieldBuilder) builder).SetCustomAttribute (cb);\r
1036                                                 }\r
1037                                         } else\r
1038                                                 throw new Exception ("Unknown kind: " + kind);\r
1039 \r
1040                                         //\r
1041                                         // Once an attribute type has been emitted once we\r
1042                                         // keep track of the info to prevent multiple occurences\r
1043                                         // for attributes which do not explicitly allow it\r
1044                                         //\r
1045                                         if (!emitted_attrs.Contains (attr_type))\r
1046                                                 emitted_attrs.Add (attr_type);\r
1047 \r
1048                                         //\r
1049                                         // We keep of this target-wise and so emitted targets\r
1050                                         // are tracked too\r
1051                                         //\r
1052                                         if (!emitted_targets.Contains (attr_target))\r
1053                                                 emitted_targets.Add (attr_target);\r
1054                                 }\r
1055                                 \r
1056                                 \r
1057                         }\r
1058                 }\r
1059 \r
1060                 public MethodBuilder DefinePInvokeMethod (EmitContext ec, TypeBuilder builder, string name,\r
1061                                                           MethodAttributes flags, Type ret_type, Type [] param_types)\r
1062                 {\r
1063                         //\r
1064                         // We extract from the attribute the information we need \r
1065                         //\r
1066 \r
1067                         if (Arguments == null) {\r
1068                                 Console.WriteLine ("Internal error : this is not supposed to happen !");\r
1069                                 return null;\r
1070                         }\r
1071 \r
1072                         Type = CheckAttributeType (ec);\r
1073                         if (Type == null)\r
1074                                 return null;\r
1075                         \r
1076                         ArrayList named_args = new ArrayList ();\r
1077                         \r
1078                         ArrayList pos_args = (ArrayList) Arguments [0];\r
1079                         if (Arguments.Count > 1)\r
1080                                 named_args = (ArrayList) Arguments [1];\r
1081                         \r
1082 \r
1083                         string dll_name = null;\r
1084                         \r
1085                         Argument tmp = (Argument) pos_args [0];\r
1086 \r
1087                         if (!tmp.Resolve (ec, Location))\r
1088                                 return null;\r
1089                         \r
1090                         if (tmp.Expr is Constant)\r
1091                                 dll_name = (string) ((Constant) tmp.Expr).GetValue ();\r
1092                         else { \r
1093                                 Error_AttributeArgumentNotValid (Location);\r
1094                                 return null;\r
1095                         }\r
1096 \r
1097                         // Now we process the named arguments\r
1098                         CallingConvention cc = CallingConvention.Winapi;\r
1099                         CharSet charset = CharSet.Ansi;\r
1100                         bool preserve_sig = true;\r
1101 #if FIXME\r
1102                         bool exact_spelling = false;\r
1103 #endif\r
1104                         bool set_last_err = false;\r
1105                         string entry_point = null;\r
1106 \r
1107                         for (int i = 0; i < named_args.Count; i++) {\r
1108 \r
1109                                 DictionaryEntry de = (DictionaryEntry) named_args [i];\r
1110 \r
1111                                 string member_name = (string) de.Key;\r
1112                                 Argument a  = (Argument) de.Value;\r
1113 \r
1114                                 if (!a.Resolve (ec, Location))\r
1115                                         return null;\r
1116 \r
1117                                 Expression member = Expression.MemberLookup (\r
1118                                         ec, Type, member_name, \r
1119                                         MemberTypes.Field | MemberTypes.Property,\r
1120                                         BindingFlags.Public | BindingFlags.Instance,\r
1121                                         Location);\r
1122 \r
1123                                 if (member == null || !(member is FieldExpr)) {\r
1124                                         Error_InvalidNamedArgument (member_name);\r
1125                                         return null;\r
1126                                 }\r
1127 \r
1128                                 if (member is FieldExpr) {\r
1129                                         FieldExpr fe = (FieldExpr) member;\r
1130                                         FieldInfo fi = fe.FieldInfo;\r
1131 \r
1132                                         if (fi.IsInitOnly) {\r
1133                                                 Error_InvalidNamedArgument (member_name);\r
1134                                                 return null;\r
1135                                         }\r
1136 \r
1137                                         if (a.Expr is Constant) {\r
1138                                                 Constant c = (Constant) a.Expr;\r
1139                                                 \r
1140                                                 if (member_name == "CallingConvention")\r
1141                                                         cc = (CallingConvention) c.GetValue ();\r
1142                                                 else if (member_name == "CharSet")\r
1143                                                         charset = (CharSet) c.GetValue ();\r
1144                                                 else if (member_name == "EntryPoint")\r
1145                                                         entry_point = (string) c.GetValue ();\r
1146                                                 else if (member_name == "SetLastError")\r
1147                                                         set_last_err = (bool) c.GetValue ();\r
1148 #if FIXME\r
1149                                                 else if (member_name == "ExactSpelling")\r
1150                                                         exact_spelling = (bool) c.GetValue ();\r
1151 #endif\r
1152                                                 else if (member_name == "PreserveSig")\r
1153                                                         preserve_sig = (bool) c.GetValue ();\r
1154                                         } else { \r
1155                                                 Error_AttributeArgumentNotValid (Location);\r
1156                                                 return null;\r
1157                                         }\r
1158                                         \r
1159                                 }\r
1160                         }\r
1161 \r
1162                         if (entry_point == null)\r
1163                                 entry_point = name;\r
1164                         if (set_last_err)\r
1165                                 charset = (CharSet)((int)charset | 0x40);\r
1166                         \r
1167                         MethodBuilder mb = builder.DefinePInvokeMethod (\r
1168                                 name, dll_name, entry_point, flags | MethodAttributes.HideBySig,\r
1169                                 CallingConventions.Standard,\r
1170                                 ret_type,\r
1171                                 param_types,\r
1172                                 cc,\r
1173                                 charset);\r
1174 \r
1175                         if (preserve_sig)\r
1176                                 mb.SetImplementationFlags (MethodImplAttributes.PreserveSig);\r
1177                         \r
1178                         return mb;\r
1179                 }\r
1180                 \r
1181         }\r
1182         \r
1183         public class AttributeSection {\r
1184                 public readonly string    Target;\r
1185                 public readonly ArrayList Attributes;\r
1186                 \r
1187                 public AttributeSection (string target, ArrayList attrs)\r
1188                 {\r
1189                         Target = target;\r
1190                         Attributes = attrs;\r
1191                 }\r
1192                 \r
1193         }\r
1194 \r
1195         public class Attributes {\r
1196                 public ArrayList AttributeSections;\r
1197 \r
1198                 public Attributes (AttributeSection a)\r
1199                 {\r
1200                         AttributeSections = new ArrayList ();\r
1201                         AttributeSections.Add (a);\r
1202 \r
1203                 }\r
1204 \r
1205                 public void AddAttributeSection (AttributeSection a)\r
1206                 {\r
1207                         if (a != null && !AttributeSections.Contains (a))\r
1208                                 AttributeSections.Add (a);\r
1209                 }\r
1210 \r
1211                 public bool Contains (Type t)\r
1212                 {\r
1213                         foreach (AttributeSection attr_section in AttributeSections){\r
1214                                 foreach (Attribute a in attr_section.Attributes){\r
1215                                         if (a.Type == t)\r
1216                                                 return true;\r
1217                                 }\r
1218                         }\r
1219                         \r
1220                         return false;\r
1221                 }\r
1222         }\r
1223
1224         public interface IAttributeSupport {
1225                 void SetCustomAttribute (CustomAttributeBuilder customBuilder);
1226         }
1227 }\r