mcs/mcs/delegate.cs

   1 //\r
   2 // delegate.cs: Delegate Handler\r
   3 //\r
   4 // Authors:\r
   5 //     Ravi Pratap (ravi@ximian.com)\r
   6 //     Miguel de Icaza (miguel@ximian.com)\r
   7 //\r
   8 // Licensed under the terms of the GNU GPL\r
   9 //\r
  10 // (C) 2001 Ximian, Inc (http://www.ximian.com)\r
  11 //\r
  12 //\r
  13 \r
  14 using System;\r
  15 using System.Collections;\r
  16 using System.Reflection;\r
  17 using System.Reflection.Emit;\r
  18 using System.Text;\r
  19 \r
  20 namespace Mono.CSharp {\r
  21 \r
  22         /// <summary>\r
  23         ///   Holds Delegates\r
  24         /// </summary>\r
  25         public class Delegate : DeclSpace {\r
  26                 public Expression ReturnType;\r
  27                 public Parameters      Parameters;\r
  28                 public Attributes      OptAttributes;\r
  29 \r
  30                 public ConstructorBuilder ConstructorBuilder;\r
  31                 public MethodBuilder      InvokeBuilder;\r
  32                 public MethodBuilder      BeginInvokeBuilder;\r
  33                 public MethodBuilder      EndInvokeBuilder;\r
  34                 \r
  35                 Type [] param_types;\r
  36                 Type ret_type;\r
  37                 \r
  38                 Expression instance_expr;\r
  39                 MethodBase delegate_method;\r
  40         \r
  41                 const int AllowedModifiers =\r
  42                         Modifiers.NEW |\r
  43                         Modifiers.PUBLIC |\r
  44                         Modifiers.PROTECTED |\r
  45                         Modifiers.INTERNAL |\r
  46                         Modifiers.UNSAFE |\r
  47                         Modifiers.PRIVATE;\r
  48 \r
  49                 public Delegate (NamespaceEntry ns, TypeContainer parent, Expression type,\r
  50                                  int mod_flags, string name, Parameters param_list,\r
  51                                  Attributes attrs, Location l)\r
  52                         : base (ns, parent, name, l)\r
  53                 {\r
  54                         this.ReturnType = type;\r
  55                         ModFlags        = Modifiers.Check (AllowedModifiers, mod_flags,\r
  56                                                            IsTopLevel ? Modifiers.INTERNAL :\r
  57                                                            Modifiers.PRIVATE, l);\r
  58                         Parameters      = param_list;\r
  59                         OptAttributes   = attrs;\r
  60                 }\r
  61 \r
  62                 public override TypeBuilder DefineType ()\r
  63                 {\r
  64                         if (TypeBuilder != null)\r
  65                                 return TypeBuilder;\r
  66 \r
  67                         TypeAttributes attr = Modifiers.TypeAttr (ModFlags, IsTopLevel) |\r
  68                                 TypeAttributes.Class | TypeAttributes.Sealed;\r
  69 \r
  70                         if (IsTopLevel) {\r
  71                                 if (TypeManager.NamespaceClash (Name, Location))\r
  72                                         return null;\r
  73                                 \r
  74                                 ModuleBuilder builder = CodeGen.ModuleBuilder;\r
  75 \r
  76                                 TypeBuilder = builder.DefineType (\r
  77                                         Name, attr, TypeManager.multicast_delegate_type);\r
  78                         } else {\r
  79                                 TypeBuilder builder = Parent.TypeBuilder;\r
  80 \r
  81                                 string name = Name.Substring (1 + Name.LastIndexOf ('.'));\r
  82                                 TypeBuilder = builder.DefineNestedType (\r
  83                                         name, attr, TypeManager.multicast_delegate_type);\r
  84                         }\r
  85 \r
  86                         TypeManager.AddDelegateType (Name, TypeBuilder, this);\r
  87 \r
  88                         return TypeBuilder;\r
  89                 }\r
  90 \r
  91                 public override bool DefineMembers (TypeContainer container)\r
  92                 {\r
  93                         return true;\r
  94                 }\r
  95 \r
  96                 public override bool Define (TypeContainer container)\r
  97                 {\r
  98                         MethodAttributes mattr;\r
  99                         int i;\r
 100                         ParameterBuilder pb;\r
 101                         Attributes cattr;\r
 102                         EmitContext ec = new EmitContext (this, this, Location, null,\r
 103                                                           null, ModFlags, false);\r
 104 \r
 105                         // FIXME: POSSIBLY make this static, as it is always constant\r
 106                         //\r
 107                         Type [] const_arg_types = new Type [2];\r
 108                         const_arg_types [0] = TypeManager.object_type;\r
 109                         const_arg_types [1] = TypeManager.intptr_type;\r
 110 \r
 111                         mattr = MethodAttributes.RTSpecialName | MethodAttributes.SpecialName |\r
 112                                 MethodAttributes.HideBySig | MethodAttributes.Public;\r
 113 \r
 114                         ConstructorBuilder = TypeBuilder.DefineConstructor (mattr,\r
 115                                                                             CallingConventions.Standard,\r
 116                                                                             const_arg_types);\r
 117 \r
 118                         ConstructorBuilder.DefineParameter (1, ParameterAttributes.None, "object");\r
 119                         ConstructorBuilder.DefineParameter (2, ParameterAttributes.None, "method");\r
 120                         //\r
 121                         // HACK because System.Reflection.Emit is lame\r
 122                         //\r
 123                         //\r
 124                         // FIXME: POSSIBLY make these static, as they are always the same\r
 125                         Parameter [] fixed_pars = new Parameter [2];\r
 126                         fixed_pars [0] = new Parameter (null, null, Parameter.Modifier.NONE, null);\r
 127                         fixed_pars [1] = new Parameter (null, null, Parameter.Modifier.NONE, null);\r
 128                         Parameters const_parameters = new Parameters (fixed_pars, null, Location);\r
 129                         \r
 130                         TypeManager.RegisterMethod (\r
 131                                 ConstructorBuilder,\r
 132                                 new InternalParameters (const_arg_types, const_parameters),\r
 133                                 const_arg_types);\r
 134                                 \r
 135                         \r
 136                         ConstructorBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);\r
 137 \r
 138                         //\r
 139                         // Here the various methods like Invoke, BeginInvoke etc are defined\r
 140                         //\r
 141                         // First, call the `out of band' special method for\r
 142                         // defining recursively any types we need:\r
 143                         \r
 144                         if (!Parameters.ComputeAndDefineParameterTypes (this))\r
 145                                 return false;\r
 146                         \r
 147                         param_types = Parameters.GetParameterInfo (this);\r
 148                         if (param_types == null)\r
 149                                 return false;\r
 150 \r
 151                         //\r
 152                         // Invoke method\r
 153                         //\r
 154 \r
 155                         // Check accessibility\r
 156                         foreach (Type partype in param_types){\r
 157                                 if (!container.AsAccessible (partype, ModFlags)) {\r
 158                                         Report.Error (59, Location,\r
 159                                                       "Inconsistent accessibility: parameter type `" +\r
 160                                                       TypeManager.CSharpName (partype) + "` is less " +\r
 161                                                       "accessible than delegate `" + Name + "'");\r
 162                                         return false;\r
 163                                 }\r
 164                                 if (partype.IsPointer && !UnsafeOK (container))\r
 165                                         return false;\r
 166                         }\r
 167                         \r
 168                         ReturnType = ResolveTypeExpr (ReturnType, false, Location);\r
 169                         ret_type = ReturnType.Type;\r
 170                         if (ret_type == null)\r
 171                                 return false;\r
 172 \r
 173                         if (!container.AsAccessible (ret_type, ModFlags)) {\r
 174                                 Report.Error (58, Location,\r
 175                                               "Inconsistent accessibility: return type `" +\r
 176                                               TypeManager.CSharpName (ret_type) + "` is less " +\r
 177                                               "accessible than delegate `" + Name + "'");\r
 178                                 return false;\r
 179                         }\r
 180 \r
 181                         if (ret_type.IsPointer && !UnsafeOK (container))\r
 182                                 return false;\r
 183 \r
 184                         //\r
 185                         // We don't have to check any others because they are all\r
 186                         // guaranteed to be accessible - they are standard types.\r
 187                         //\r
 188                         \r
 189                         CallingConventions cc = Parameters.GetCallingConvention ();\r
 190 \r
 191                         mattr = MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.Virtual;\r
 192 \r
 193                         InvokeBuilder = TypeBuilder.DefineMethod ("Invoke", \r
 194                                                                   mattr,                     \r
 195                                                                   cc,\r
 196                                                                   ret_type,                  \r
 197                                                                   param_types);\r
 198 \r
 199                         //\r
 200                         // Define parameters, and count out/ref parameters\r
 201                         //\r
 202                         int out_params = 0;\r
 203                         i = 0;\r
 204                         if (Parameters.FixedParameters != null){\r
 205                                 int top = Parameters.FixedParameters.Length;\r
 206                                 Parameter p;\r
 207                                 \r
 208                                 for (; i < top; i++) {\r
 209                                         p = Parameters.FixedParameters [i];\r
 210                                         pb = InvokeBuilder.DefineParameter (i+1, p.Attributes, p.Name);\r
 211                                         cattr = p.OptAttributes;\r
 212                                         if (cattr != null)\r
 213                                                 Attribute.ApplyAttributes (ec, pb, pb, cattr);\r
 214 \r
 215                                         if ((p.ModFlags & Parameter.Modifier.ISBYREF) != 0)\r
 216                                                 out_params++;\r
 217                                 }\r
 218                         }\r
 219                         if (Parameters.ArrayParameter != null){\r
 220                                 Parameter p = Parameters.ArrayParameter;\r
 221                                 \r
 222                                 pb = InvokeBuilder.DefineParameter (\r
 223                                         i+1, p.Attributes, p.Name);\r
 224                                 cattr = p.OptAttributes;\r
 225                                 if (cattr != null)\r
 226                                         Attribute.ApplyAttributes (ec, pb, pb, cattr);\r
 227                         }\r
 228                         \r
 229                         InvokeBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);\r
 230 \r
 231                         TypeManager.RegisterMethod (InvokeBuilder,\r
 232                                                     new InternalParameters (container, Parameters),\r
 233                                                     param_types);\r
 234 \r
 235                         //\r
 236                         // BeginInvoke\r
 237                         //\r
 238                         int params_num = param_types.Length;\r
 239                         Type [] async_param_types = new Type [params_num + 2];\r
 240 \r
 241                         param_types.CopyTo (async_param_types, 0);\r
 242 \r
 243                         async_param_types [params_num] = TypeManager.asynccallback_type;\r
 244                         async_param_types [params_num + 1] = TypeManager.object_type;\r
 245 \r
 246                         mattr = MethodAttributes.Public | MethodAttributes.HideBySig |\r
 247                                 MethodAttributes.Virtual | MethodAttributes.NewSlot;\r
 248                         \r
 249                         BeginInvokeBuilder = TypeBuilder.DefineMethod ("BeginInvoke",\r
 250                                                                        mattr,\r
 251                                                                        cc,\r
 252                                                                        TypeManager.iasyncresult_type,\r
 253                                                                        async_param_types);\r
 254 \r
 255                         i = 0;\r
 256                         if (Parameters.FixedParameters != null){\r
 257                                 int top = Parameters.FixedParameters.Length;\r
 258                                 Parameter p;\r
 259                                 \r
 260                                 for (i = 0 ; i < top; i++) {\r
 261                                         p = Parameters.FixedParameters [i];\r
 262 \r
 263                                         pb = BeginInvokeBuilder.DefineParameter (i+1, p.Attributes, p.Name);\r
 264                                         cattr = p.OptAttributes;\r
 265                                         if (cattr != null)\r
 266                                                 Attribute.ApplyAttributes (ec, pb, pb, cattr);\r
 267                                 }\r
 268                         }\r
 269                         if (Parameters.ArrayParameter != null){\r
 270                                 Parameter p = Parameters.ArrayParameter;\r
 271                                 \r
 272                                 pb = BeginInvokeBuilder.DefineParameter (i+1, p.Attributes, p.Name);\r
 273                                 cattr = p.OptAttributes;\r
 274                                 if (cattr != null)\r
 275                                         Attribute.ApplyAttributes (ec, pb, pb, cattr);\r
 276                                 i++;\r
 277                         }\r
 278 \r
 279                         BeginInvokeBuilder.DefineParameter (i + 1, ParameterAttributes.None, "callback");\r
 280                         BeginInvokeBuilder.DefineParameter (i + 2, ParameterAttributes.None, "object");\r
 281                         \r
 282                         BeginInvokeBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);\r
 283 \r
 284                         Parameter [] async_params = new Parameter [params_num + 2];\r
 285                         int n = 0;\r
 286                         if (Parameters.FixedParameters != null){\r
 287                                 Parameters.FixedParameters.CopyTo (async_params, 0);\r
 288                                 n = Parameters.FixedParameters.Length;\r
 289                         }\r
 290                         if (Parameters.ArrayParameter != null)\r
 291                                 async_params [n] = Parameters.ArrayParameter;\r
 292                         \r
 293                         async_params [params_num] = new Parameter (\r
 294                                 TypeManager.system_asynccallback_expr, "callback",\r
 295                                                                    Parameter.Modifier.NONE, null);\r
 296                         async_params [params_num + 1] = new Parameter (\r
 297                                 TypeManager.system_object_expr, "object",\r
 298                                                                    Parameter.Modifier.NONE, null);\r
 299 \r
 300                         Parameters async_parameters = new Parameters (async_params, null, Location);\r
 301                         async_parameters.ComputeAndDefineParameterTypes (this);\r
 302                         \r
 303                         async_parameters.ComputeAndDefineParameterTypes (this);\r
 304                         TypeManager.RegisterMethod (BeginInvokeBuilder,\r
 305                                                     new InternalParameters (container, async_parameters),\r
 306                                                     async_param_types);\r
 307 \r
 308                         //\r
 309                         // EndInvoke is a bit more interesting, all the parameters labeled as\r
 310                         // out or ref have to be duplicated here.\r
 311                         //\r
 312                         \r
 313                         Type [] end_param_types = new Type [out_params + 1];\r
 314                         Parameter [] end_params = new Parameter [out_params + 1];\r
 315                         int param = 0; \r
 316                         if (out_params > 0){\r
 317                                 int top = Parameters.FixedParameters.Length;\r
 318                                 for (i = 0; i < top; i++){\r
 319                                         Parameter p = Parameters.FixedParameters [i];\r
 320                                         if ((p.ModFlags & Parameter.Modifier.ISBYREF) == 0)\r
 321                                                 continue;\r
 322 \r
 323                                         end_param_types [param] = param_types [i];\r
 324                                         end_params [param] = p;\r
 325                                         param++;\r
 326                                 }\r
 327                         }\r
 328                         end_param_types [out_params] = TypeManager.iasyncresult_type;\r
 329                         end_params [out_params] = new Parameter (TypeManager.system_iasyncresult_expr, "result", Parameter.Modifier.NONE, null);\r
 330 \r
 331                         //\r
 332                         // Create method, define parameters, register parameters with type system\r
 333                         //\r
 334                         EndInvokeBuilder = TypeBuilder.DefineMethod ("EndInvoke", mattr, cc, ret_type, end_param_types);\r
 335                         EndInvokeBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);\r
 336 \r
 337                         //\r
 338                         // EndInvoke: Label the parameters\r
 339                         //\r
 340                         EndInvokeBuilder.DefineParameter (out_params + 1, ParameterAttributes.None, "result");\r
 341                         for (i = 0; i < end_params.Length-1; i++){\r
 342                                 EndInvokeBuilder.DefineParameter (i + 1, end_params [i].Attributes, end_params [i].Name);\r
 343                         }\r
 344 \r
 345                         Parameters end_parameters = new Parameters (end_params, null, Location);\r
 346                         end_parameters.ComputeAndDefineParameterTypes (this);\r
 347 \r
 348                         TypeManager.RegisterMethod (\r
 349                                 EndInvokeBuilder,\r
 350                                 new InternalParameters (container, end_parameters),\r
 351                                 end_param_types);\r
 352 \r
 353                         return true;\r
 354                 }\r
 355 \r
 356                 /// <summary>\r
 357                 ///  Verifies whether the method in question is compatible with the delegate\r
 358                 ///  Returns the method itself if okay and null if not.\r
 359                 /// </summary>\r
 360                 public static MethodBase VerifyMethod (EmitContext ec, Type delegate_type, MethodBase mb,\r
 361                                                        Location loc)\r
 362                 {\r
 363                         ParameterData pd = Invocation.GetParameterData (mb);\r
 364 \r
 365                         int pd_count = pd.Count;\r
 366 \r
 367                         Expression ml = Expression.MemberLookup (\r
 368                                 ec, delegate_type, "Invoke", loc);\r
 369 \r
 370                         if (!(ml is MethodGroupExpr)) {\r
 371                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 372                                 return null;\r
 373                         }\r
 374 \r
 375                         MethodBase invoke_mb = ((MethodGroupExpr) ml).Methods [0];\r
 376 \r
 377                         ParameterData invoke_pd = Invocation.GetParameterData (invoke_mb);\r
 378 \r
 379                         if (invoke_pd.Count != pd_count)\r
 380                                 return null;\r
 381 \r
 382                         for (int i = pd_count; i > 0; ) {\r
 383                                 i--;\r
 384 \r
 385                                 if (invoke_pd.ParameterType (i) == pd.ParameterType (i) &&\r
 386                                     invoke_pd.ParameterModifier (i) == pd.ParameterModifier (i))\r
 387                                         continue;\r
 388                                 else {\r
 389                                         return null;\r
 390                                 }\r
 391                         }\r
 392 \r
 393                         if (((MethodInfo) invoke_mb).ReturnType == ((MethodInfo) mb).ReturnType)\r
 394                                 return mb;\r
 395                         else\r
 396                                 return null;\r
 397                 }\r
 398 \r
 399                 // <summary>\r
 400                 //  Verifies whether the invocation arguments are compatible with the\r
 401                 //  delegate's target method\r
 402                 // </summary>\r
 403                 public static bool VerifyApplicability (EmitContext ec,\r
 404                                                         Type delegate_type,\r
 405                                                         ArrayList args,\r
 406                                                         Location loc)\r
 407                 {\r
 408                         int arg_count;\r
 409 \r
 410                         if (args == null)\r
 411                                 arg_count = 0;\r
 412                         else\r
 413                                 arg_count = args.Count;\r
 414 \r
 415                         Expression ml = Expression.MemberLookup (\r
 416                                 ec, delegate_type, "Invoke", loc);\r
 417 \r
 418                         if (!(ml is MethodGroupExpr)) {\r
 419                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!" + delegate_type);\r
 420                                 return false;\r
 421                         }\r
 422                         \r
 423                         MethodBase mb = ((MethodGroupExpr) ml).Methods [0];\r
 424                         ParameterData pd = Invocation.GetParameterData (mb);\r
 425 \r
 426                         int pd_count = pd.Count;\r
 427 \r
 428                         bool not_params_method = (pd_count == 0) ||\r
 429                                 (pd.ParameterModifier (pd_count - 1) != Parameter.Modifier.PARAMS);\r
 430 \r
 431                         if (not_params_method && pd_count != arg_count) {\r
 432                                 Report.Error (1593, loc,\r
 433                                               "Delegate '" + delegate_type.ToString ()\r
 434                                               + "' does not take '" + arg_count + "' arguments");\r
 435                                 return false;\r
 436                         }\r
 437 \r
 438                         return Invocation.VerifyArgumentsCompat (ec, args, arg_count, mb, !not_params_method,\r
 439                                                                  delegate_type, loc);\r
 440                 }\r
 441                 \r
 442                 /// <summary>\r
 443                 ///  Verifies whether the delegate in question is compatible with this one in\r
 444                 ///  order to determine if instantiation from the same is possible.\r
 445                 /// </summary>\r
 446                 public static bool VerifyDelegate (EmitContext ec, Type delegate_type, Type probe_type, Location loc)\r
 447                 {\r
 448                         Expression ml = Expression.MemberLookup (\r
 449                                 ec, delegate_type, "Invoke", loc);\r
 450                         \r
 451                         if (!(ml is MethodGroupExpr)) {\r
 452                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 453                                 return false;\r
 454                         }\r
 455                         \r
 456                         MethodBase mb = ((MethodGroupExpr) ml).Methods [0];\r
 457                         ParameterData pd = Invocation.GetParameterData (mb);\r
 458 \r
 459                         Expression probe_ml = Expression.MemberLookup (\r
 460                                 ec, delegate_type, "Invoke", loc);\r
 461                         \r
 462                         if (!(probe_ml is MethodGroupExpr)) {\r
 463                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 464                                 return false;\r
 465                         }\r
 466                         \r
 467                         MethodBase probe_mb = ((MethodGroupExpr) probe_ml).Methods [0];\r
 468                         ParameterData probe_pd = Invocation.GetParameterData (probe_mb);\r
 469                         \r
 470                         if (((MethodInfo) mb).ReturnType != ((MethodInfo) probe_mb).ReturnType)\r
 471                                 return false;\r
 472 \r
 473                         if (pd.Count != probe_pd.Count)\r
 474                                 return false;\r
 475 \r
 476                         for (int i = pd.Count; i > 0; ) {\r
 477                                 i--;\r
 478 \r
 479                                 if (pd.ParameterType (i) != probe_pd.ParameterType (i) ||\r
 480                                     pd.ParameterModifier (i) != probe_pd.ParameterModifier (i))\r
 481                                         return false;\r
 482                         }\r
 483                         \r
 484                         return true;\r
 485                 }\r
 486                 \r
 487                 public static string FullDelegateDesc (Type del_type, MethodBase mb, ParameterData pd)\r
 488                 {\r
 489                         StringBuilder sb = new StringBuilder (TypeManager.CSharpName (((MethodInfo) mb).ReturnType));\r
 490                         \r
 491                         sb.Append (" " + del_type.ToString ());\r
 492                         sb.Append (" (");\r
 493 \r
 494                         int length = pd.Count;\r
 495                         \r
 496                         for (int i = length; i > 0; ) {\r
 497                                 i--;\r
 498 \r
 499                                 sb.Append (pd.ParameterDesc (length - i - 1));\r
 500                                 if (i != 0)\r
 501                                         sb.Append (", ");\r
 502                         }\r
 503                         \r
 504                         sb.Append (")");\r
 505                         return sb.ToString ();\r
 506                         \r
 507                 }\r
 508                 \r
 509                 // Hack around System.Reflection as found everywhere else\r
 510                 public override MemberList FindMembers (MemberTypes mt, BindingFlags bf,\r
 511                                                         MemberFilter filter, object criteria)\r
 512                 {\r
 513                         ArrayList members = new ArrayList ();\r
 514 \r
 515                         if ((mt & MemberTypes.Method) != 0) {\r
 516                                 if (ConstructorBuilder != null)\r
 517                                 if (filter (ConstructorBuilder, criteria))\r
 518                                         members.Add (ConstructorBuilder);\r
 519 \r
 520                                 if (InvokeBuilder != null)\r
 521                                 if (filter (InvokeBuilder, criteria))\r
 522                                         members.Add (InvokeBuilder);\r
 523 \r
 524                                 if (BeginInvokeBuilder != null)\r
 525                                 if (filter (BeginInvokeBuilder, criteria))\r
 526                                         members.Add (BeginInvokeBuilder);\r
 527 \r
 528                                 if (EndInvokeBuilder != null)\r
 529                                 if (filter (EndInvokeBuilder, criteria))\r
 530                                         members.Add (EndInvokeBuilder);\r
 531                         }\r
 532 \r
 533                         return new MemberList (members);\r
 534                 }\r
 535 \r
 536                 public override MemberCache MemberCache {\r
 537                         get {\r
 538                                 return null;\r
 539                         }\r
 540                 }\r
 541 \r
 542                 public Expression InstanceExpression {\r
 543                         get {\r
 544                                 return instance_expr;\r
 545                         }\r
 546                         set {\r
 547                                 instance_expr = value;\r
 548                         }\r
 549                 }\r
 550 \r
 551                 public MethodBase TargetMethod {\r
 552                         get {\r
 553                                 return delegate_method;\r
 554                         }\r
 555                         set {\r
 556                                 delegate_method = value;\r
 557                         }\r
 558                 }\r
 559 \r
 560                 public Type TargetReturnType {\r
 561                         get {\r
 562                                 return ret_type;\r
 563                         }\r
 564                 }\r
 565 \r
 566                 public Type [] ParameterTypes {\r
 567                         get {\r
 568                                 return param_types;\r
 569                         }\r
 570                 }\r
 571                 \r
 572         }\r
 573 \r
 574         public class NewDelegate : Expression {\r
 575 \r
 576                 public ArrayList Arguments;\r
 577 \r
 578                 MethodBase constructor_method;\r
 579                 MethodBase delegate_method;\r
 580                 Expression delegate_instance_expr;\r
 581 \r
 582                 public NewDelegate (Type type, ArrayList Arguments, Location loc)\r
 583                 {\r
 584                         this.type = type;\r
 585                         this.Arguments = Arguments;\r
 586                         this.loc  = loc; \r
 587                 }\r
 588 \r
 589                 public override Expression DoResolve (EmitContext ec)\r
 590                 {\r
 591                         if (Arguments == null || Arguments.Count != 1) {\r
 592                                 Report.Error (149, loc,\r
 593                                               "Method name expected");\r
 594                                 return null;\r
 595                         }\r
 596 \r
 597                         Expression ml = Expression.MemberLookup (\r
 598                                 ec, type, ".ctor", loc);\r
 599 \r
 600                         if (!(ml is MethodGroupExpr)) {\r
 601                                 Report.Error (-100, loc, "Internal error: Could not find delegate constructor!");\r
 602                                 return null;\r
 603                         }\r
 604 \r
 605                         constructor_method = ((MethodGroupExpr) ml).Methods [0];\r
 606                         Argument a = (Argument) Arguments [0];\r
 607                         \r
 608                         if (!a.ResolveMethodGroup (ec, Location))\r
 609                                 return null;\r
 610                         \r
 611                         Expression e = a.Expr;\r
 612 \r
 613                         Expression invoke_method = Expression.MemberLookup (\r
 614                                 ec, type, "Invoke", MemberTypes.Method,\r
 615                                 Expression.AllBindingFlags, loc);\r
 616 \r
 617                         if (invoke_method == null) {\r
 618                                 Report.Error (-200, loc, "Internal error ! Could not find Invoke method!");\r
 619                                 return null;\r
 620                         }\r
 621 \r
 622                         if (e is MethodGroupExpr) {\r
 623                                 MethodGroupExpr mg = (MethodGroupExpr) e;\r
 624 \r
 625                                 foreach (MethodInfo mi in mg.Methods){\r
 626                                         delegate_method  = Delegate.VerifyMethod (ec, type, mi, loc);\r
 627 \r
 628                                         if (delegate_method != null)\r
 629                                                 break;\r
 630                                 }\r
 631                                         \r
 632                                 if (delegate_method == null) {\r
 633                                         string method_desc;\r
 634                                         if (mg.Methods.Length > 1)\r
 635                                                 method_desc = mg.Methods [0].Name;\r
 636                                         else\r
 637                                                 method_desc = Invocation.FullMethodDesc (mg.Methods [0]);\r
 638 \r
 639                                         MethodBase dm = ((MethodGroupExpr) invoke_method).Methods [0];\r
 640                                         ParameterData param = Invocation.GetParameterData (dm);\r
 641                                         string delegate_desc = Delegate.FullDelegateDesc (type, dm, param);\r
 642 \r
 643                                         Report.Error (123, loc, "Method '" + method_desc + "' does not " +\r
 644                                                       "match delegate '" + delegate_desc + "'");\r
 645 \r
 646                                         return null;\r
 647                                 }\r
 648 \r
 649                                 //\r
 650                                 // Check safe/unsafe of the delegate\r
 651                                 //\r
 652                                 if (!ec.InUnsafe){\r
 653                                         ParameterData param = Invocation.GetParameterData (delegate_method);\r
 654                                         int count = param.Count;\r
 655                                         \r
 656                                         for (int i = 0; i < count; i++){\r
 657                                                 if (param.ParameterType (i).IsPointer){\r
 658                                                         Expression.UnsafeError (loc);\r
 659                                                         return null;\r
 660                                                 }\r
 661                                         }\r
 662                                 }\r
 663                                                 \r
 664                                 if (mg.InstanceExpression != null)\r
 665                                         delegate_instance_expr = mg.InstanceExpression.Resolve (ec);\r
 666                                 else {\r
 667                                         if (ec.IsStatic){\r
 668                                                 if (!delegate_method.IsStatic){\r
 669                                                         Report.Error (120, loc,\r
 670                                                                       "An object reference is required for the non-static method " +\r
 671                                                                       delegate_method.Name);\r
 672                                                         return null;\r
 673                                                 }\r
 674                                                 delegate_instance_expr = null;\r
 675                                         } else\r
 676                                                 delegate_instance_expr = ec.GetThis (loc);\r
 677                                 }\r
 678 \r
 679                                 if (delegate_instance_expr != null)\r
 680                                         if (delegate_instance_expr.Type.IsValueType)\r
 681                                                 delegate_instance_expr = new BoxedCast (delegate_instance_expr);\r
 682                                 \r
 683                                 eclass = ExprClass.Value;\r
 684                                 return this;\r
 685                         }\r
 686 \r
 687                         Type e_type = e.Type;\r
 688 \r
 689                         if (!TypeManager.IsDelegateType (e_type)) {\r
 690                                 e.Error_UnexpectedKind ("method");\r
 691                                 return null;\r
 692                         }\r
 693 \r
 694                         // This is what MS' compiler reports. We could always choose\r
 695                         // to be more verbose and actually give delegate-level specifics\r
 696                         \r
 697                         if (!Delegate.VerifyDelegate (ec, type, e_type, loc)) {\r
 698                                 Report.Error (29, loc, "Cannot implicitly convert type '" + e_type + "' " +\r
 699                                               "to type '" + type + "'");\r
 700                                 return null;\r
 701                         }\r
 702                                 \r
 703                         delegate_instance_expr = e;\r
 704                         delegate_method = ((MethodGroupExpr) invoke_method).Methods [0];\r
 705                         \r
 706                         eclass = ExprClass.Value;\r
 707                         return this;\r
 708                 }\r
 709                 \r
 710                 public override void Emit (EmitContext ec)\r
 711                 {\r
 712                         if (delegate_instance_expr == null ||\r
 713                             delegate_method.IsStatic)\r
 714                                 ec.ig.Emit (OpCodes.Ldnull);\r
 715                         else\r
 716                                 delegate_instance_expr.Emit (ec);\r
 717                         \r
 718                         if (delegate_method.IsVirtual) {\r
 719                                 ec.ig.Emit (OpCodes.Dup);\r
 720                                 ec.ig.Emit (OpCodes.Ldvirtftn, (MethodInfo) delegate_method);\r
 721                         } else\r
 722                                 ec.ig.Emit (OpCodes.Ldftn, (MethodInfo) delegate_method);\r
 723                         ec.ig.Emit (OpCodes.Newobj, (ConstructorInfo) constructor_method);\r
 724                 }\r
 725         }\r
 726 \r
 727         public class DelegateInvocation : ExpressionStatement {\r
 728 \r
 729                 public Expression InstanceExpr;\r
 730                 public ArrayList  Arguments;\r
 731 \r
 732                 MethodBase method;\r
 733                 \r
 734                 public DelegateInvocation (Expression instance_expr, ArrayList args, Location loc)\r
 735                 {\r
 736                         this.InstanceExpr = instance_expr;\r
 737                         this.Arguments = args;\r
 738                         this.loc = loc;\r
 739                 }\r
 740 \r
 741                 public override Expression DoResolve (EmitContext ec)\r
 742                 {\r
 743                         if (InstanceExpr is EventExpr) {\r
 744                                 \r
 745                                 EventInfo ei = ((EventExpr) InstanceExpr).EventInfo;\r
 746                                 \r
 747                                 Expression ml = MemberLookup (\r
 748                                         ec, ec.ContainerType, ei.Name,\r
 749                                         MemberTypes.Event, AllBindingFlags | BindingFlags.DeclaredOnly, loc);\r
 750 \r
 751                                 if (ml == null) {\r
 752                                         //\r
 753                                         // If this is the case, then the Event does not belong \r
 754                                         // to this Type and so, according to the spec\r
 755                                         // cannot be accessed directly\r
 756                                         //\r
 757                                         // Note that target will not appear as an EventExpr\r
 758                                         // in the case it is being referenced within the same type container;\r
 759                                         // it will appear as a FieldExpr in that case.\r
 760                                         //\r
 761                                         \r
 762                                         Assign.error70 (ei, loc);\r
 763                                         return null;\r
 764                                 }\r
 765                         }\r
 766                         \r
 767                         \r
 768                         Type del_type = InstanceExpr.Type;\r
 769                         if (del_type == null)\r
 770                                 return null;\r
 771                         \r
 772                         if (Arguments != null){\r
 773                                 foreach (Argument a in Arguments){\r
 774                                         if (!a.Resolve (ec, loc))\r
 775                                                 return null;\r
 776                                 }\r
 777                         }\r
 778                         \r
 779                         if (!Delegate.VerifyApplicability (ec, del_type, Arguments, loc))\r
 780                                 return null;\r
 781 \r
 782                         Expression lookup = Expression.MemberLookup (ec, del_type, "Invoke", loc);\r
 783                         if (!(lookup is MethodGroupExpr)) {\r
 784                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 785                                 return null;\r
 786                         }\r
 787                         \r
 788                         method = ((MethodGroupExpr) lookup).Methods [0];\r
 789                         type = ((MethodInfo) method).ReturnType;\r
 790                         eclass = ExprClass.Value;\r
 791                         \r
 792                         return this;\r
 793                 }\r
 794 \r
 795                 public override void Emit (EmitContext ec)\r
 796                 {\r
 797                         Delegate del = TypeManager.LookupDelegate (InstanceExpr.Type);\r
 798 \r
 799                         //\r
 800                         // Invocation on delegates call the virtual Invoke member\r
 801                         // so we are always `instance' calls\r
 802                         //\r
 803                         Invocation.EmitCall (ec, false, false, InstanceExpr, method, Arguments, loc);\r
 804                 }\r
 805 \r
 806                 public override void EmitStatement (EmitContext ec)\r
 807                 {\r
 808                         Emit (ec);\r
 809                         // \r
 810                         // Pop the return value if there is one\r
 811                         //\r
 812                         if (method is MethodInfo){\r
 813                                 if (((MethodInfo) method).ReturnType != TypeManager.void_type)\r
 814                                         ec.ig.Emit (OpCodes.Pop);\r
 815                         }\r
 816                 }\r
 817 \r
 818         }\r
 819 }\r