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