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                         Attribute.ApplyAttributes (ec, TypeBuilder, this, OptAttributes);\r
 354                         return true;\r
 355                 }\r
 356 \r
 357                 /// <summary>\r
 358                 ///  Verifies whether the method in question is compatible with the delegate\r
 359                 ///  Returns the method itself if okay and null if not.\r
 360                 /// </summary>\r
 361                 public static MethodBase VerifyMethod (EmitContext ec, Type delegate_type, MethodBase mb,\r
 362                                                        Location loc)\r
 363                 {\r
 364                         ParameterData pd = Invocation.GetParameterData (mb);\r
 365 \r
 366                         int pd_count = pd.Count;\r
 367 \r
 368                         Expression ml = Expression.MemberLookup (\r
 369                                 ec, delegate_type, "Invoke", loc);\r
 370 \r
 371                         if (!(ml is MethodGroupExpr)) {\r
 372                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 373                                 return null;\r
 374                         }\r
 375 \r
 376                         MethodBase invoke_mb = ((MethodGroupExpr) ml).Methods [0];\r
 377 \r
 378                         ParameterData invoke_pd = Invocation.GetParameterData (invoke_mb);\r
 379 \r
 380                         if (invoke_pd.Count != pd_count)\r
 381                                 return null;\r
 382 \r
 383                         for (int i = pd_count; i > 0; ) {\r
 384                                 i--;\r
 385 \r
 386                                 if (invoke_pd.ParameterType (i) == pd.ParameterType (i) &&\r
 387                                     invoke_pd.ParameterModifier (i) == pd.ParameterModifier (i))\r
 388                                         continue;\r
 389                                 else {\r
 390                                         return null;\r
 391                                 }\r
 392                         }\r
 393 \r
 394                         if (((MethodInfo) invoke_mb).ReturnType == ((MethodInfo) mb).ReturnType)\r
 395                                 return mb;\r
 396                         else\r
 397                                 return null;\r
 398                 }\r
 399 \r
 400                 // <summary>\r
 401                 //  Verifies whether the invocation arguments are compatible with the\r
 402                 //  delegate's target method\r
 403                 // </summary>\r
 404                 public static bool VerifyApplicability (EmitContext ec,\r
 405                                                         Type delegate_type,\r
 406                                                         ArrayList args,\r
 407                                                         Location loc)\r
 408                 {\r
 409                         int arg_count;\r
 410 \r
 411                         if (args == null)\r
 412                                 arg_count = 0;\r
 413                         else\r
 414                                 arg_count = args.Count;\r
 415 \r
 416                         Expression ml = Expression.MemberLookup (\r
 417                                 ec, delegate_type, "Invoke", loc);\r
 418 \r
 419                         if (!(ml is MethodGroupExpr)) {\r
 420                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!" + delegate_type);\r
 421                                 return false;\r
 422                         }\r
 423                         \r
 424                         MethodBase mb = ((MethodGroupExpr) ml).Methods [0];\r
 425                         ParameterData pd = Invocation.GetParameterData (mb);\r
 426 \r
 427                         int pd_count = pd.Count;\r
 428 \r
 429                         bool not_params_method = (pd_count == 0) ||\r
 430                                 (pd.ParameterModifier (pd_count - 1) != Parameter.Modifier.PARAMS);\r
 431 \r
 432                         if (not_params_method && pd_count != arg_count) {\r
 433                                 Report.Error (1593, loc,\r
 434                                               "Delegate '" + delegate_type.ToString ()\r
 435                                               + "' does not take '" + arg_count + "' arguments");\r
 436                                 return false;\r
 437                         }\r
 438 \r
 439                         return Invocation.VerifyArgumentsCompat (ec, args, arg_count, mb, !not_params_method,\r
 440                                                                  delegate_type, loc);\r
 441                 }\r
 442                 \r
 443                 /// <summary>\r
 444                 ///  Verifies whether the delegate in question is compatible with this one in\r
 445                 ///  order to determine if instantiation from the same is possible.\r
 446                 /// </summary>\r
 447                 public static bool VerifyDelegate (EmitContext ec, Type delegate_type, Type probe_type, Location loc)\r
 448                 {\r
 449                         Expression ml = Expression.MemberLookup (\r
 450                                 ec, delegate_type, "Invoke", loc);\r
 451                         \r
 452                         if (!(ml is MethodGroupExpr)) {\r
 453                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 454                                 return false;\r
 455                         }\r
 456                         \r
 457                         MethodBase mb = ((MethodGroupExpr) ml).Methods [0];\r
 458                         ParameterData pd = Invocation.GetParameterData (mb);\r
 459 \r
 460                         Expression probe_ml = Expression.MemberLookup (\r
 461                                 ec, delegate_type, "Invoke", loc);\r
 462                         \r
 463                         if (!(probe_ml is MethodGroupExpr)) {\r
 464                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 465                                 return false;\r
 466                         }\r
 467                         \r
 468                         MethodBase probe_mb = ((MethodGroupExpr) probe_ml).Methods [0];\r
 469                         ParameterData probe_pd = Invocation.GetParameterData (probe_mb);\r
 470                         \r
 471                         if (((MethodInfo) mb).ReturnType != ((MethodInfo) probe_mb).ReturnType)\r
 472                                 return false;\r
 473 \r
 474                         if (pd.Count != probe_pd.Count)\r
 475                                 return false;\r
 476 \r
 477                         for (int i = pd.Count; i > 0; ) {\r
 478                                 i--;\r
 479 \r
 480                                 if (pd.ParameterType (i) != probe_pd.ParameterType (i) ||\r
 481                                     pd.ParameterModifier (i) != probe_pd.ParameterModifier (i))\r
 482                                         return false;\r
 483                         }\r
 484                         \r
 485                         return true;\r
 486                 }\r
 487                 \r
 488                 public static string FullDelegateDesc (Type del_type, MethodBase mb, ParameterData pd)\r
 489                 {\r
 490                         StringBuilder sb = new StringBuilder (TypeManager.CSharpName (((MethodInfo) mb).ReturnType));\r
 491                         \r
 492                         sb.Append (" " + del_type.ToString ());\r
 493                         sb.Append (" (");\r
 494 \r
 495                         int length = pd.Count;\r
 496                         \r
 497                         for (int i = length; i > 0; ) {\r
 498                                 i--;\r
 499 \r
 500                                 sb.Append (pd.ParameterDesc (length - i - 1));\r
 501                                 if (i != 0)\r
 502                                         sb.Append (", ");\r
 503                         }\r
 504                         \r
 505                         sb.Append (")");\r
 506                         return sb.ToString ();\r
 507                         \r
 508                 }\r
 509                 \r
 510                 // Hack around System.Reflection as found everywhere else\r
 511                 public override MemberList FindMembers (MemberTypes mt, BindingFlags bf,\r
 512                                                         MemberFilter filter, object criteria)\r
 513                 {\r
 514                         ArrayList members = new ArrayList ();\r
 515 \r
 516                         if ((mt & MemberTypes.Method) != 0) {\r
 517                                 if (ConstructorBuilder != null)\r
 518                                 if (filter (ConstructorBuilder, criteria))\r
 519                                         members.Add (ConstructorBuilder);\r
 520 \r
 521                                 if (InvokeBuilder != null)\r
 522                                 if (filter (InvokeBuilder, criteria))\r
 523                                         members.Add (InvokeBuilder);\r
 524 \r
 525                                 if (BeginInvokeBuilder != null)\r
 526                                 if (filter (BeginInvokeBuilder, criteria))\r
 527                                         members.Add (BeginInvokeBuilder);\r
 528 \r
 529                                 if (EndInvokeBuilder != null)\r
 530                                 if (filter (EndInvokeBuilder, criteria))\r
 531                                         members.Add (EndInvokeBuilder);\r
 532                         }\r
 533 \r
 534                         return new MemberList (members);\r
 535                 }\r
 536 \r
 537                 public override MemberCache MemberCache {\r
 538                         get {\r
 539                                 return null;\r
 540                         }\r
 541                 }\r
 542 \r
 543                 public Expression InstanceExpression {\r
 544                         get {\r
 545                                 return instance_expr;\r
 546                         }\r
 547                         set {\r
 548                                 instance_expr = value;\r
 549                         }\r
 550                 }\r
 551 \r
 552                 public MethodBase TargetMethod {\r
 553                         get {\r
 554                                 return delegate_method;\r
 555                         }\r
 556                         set {\r
 557                                 delegate_method = value;\r
 558                         }\r
 559                 }\r
 560 \r
 561                 public Type TargetReturnType {\r
 562                         get {\r
 563                                 return ret_type;\r
 564                         }\r
 565                 }\r
 566 \r
 567                 public Type [] ParameterTypes {\r
 568                         get {\r
 569                                 return param_types;\r
 570                         }\r
 571                 }\r
 572                 \r
 573         }\r
 574 \r
 575         //\r
 576         // Base class for `NewDelegate' and `ImplicitDelegateCreation'\r
 577         //\r
 578         public abstract class DelegateCreation : Expression {\r
 579                 protected MethodBase constructor_method;\r
 580                 protected MethodBase delegate_method;\r
 581                 protected Expression delegate_instance_expr;\r
 582 \r
 583                 public DelegateCreation () {}\r
 584 \r
 585                 public static void Error_NoMatchingMethodForDelegate (MethodGroupExpr mg, Type t, MethodBase method, Location loc)\r
 586                 {\r
 587                         string method_desc;\r
 588                         \r
 589                         if (mg.Methods.Length > 1)\r
 590                                 method_desc = mg.Methods [0].Name;\r
 591                         else\r
 592                                 method_desc = Invocation.FullMethodDesc (mg.Methods [0]);\r
 593 \r
 594                         ParameterData param = Invocation.GetParameterData (method);\r
 595                         string delegate_desc = Delegate.FullDelegateDesc (t, method, param);\r
 596                         \r
 597                         Report.Error (123, loc, "Method '" + method_desc + "' does not " +\r
 598                                       "match delegate '" + delegate_desc + "'");\r
 599                 }\r
 600                 \r
 601                 public override void Emit (EmitContext ec)\r
 602                 {\r
 603                         if (delegate_instance_expr == null ||\r
 604                             delegate_method.IsStatic)\r
 605                                 ec.ig.Emit (OpCodes.Ldnull);\r
 606                         else\r
 607                                 delegate_instance_expr.Emit (ec);\r
 608                         \r
 609                         if (delegate_method.IsVirtual) {\r
 610                                 ec.ig.Emit (OpCodes.Dup);\r
 611                                 ec.ig.Emit (OpCodes.Ldvirtftn, (MethodInfo) delegate_method);\r
 612                         } else\r
 613                                 ec.ig.Emit (OpCodes.Ldftn, (MethodInfo) delegate_method);\r
 614                         ec.ig.Emit (OpCodes.Newobj, (ConstructorInfo) constructor_method);\r
 615                 }\r
 616 \r
 617                 protected bool ResolveConstructorMethod (EmitContext ec)\r
 618                 {\r
 619                         Expression ml = Expression.MemberLookup (\r
 620                                 ec, type, ".ctor", loc);\r
 621 \r
 622                         if (!(ml is MethodGroupExpr)) {\r
 623                                 Report.Error (-100, loc, "Internal error: Could not find delegate constructor!");\r
 624                                 return false;\r
 625                         }\r
 626 \r
 627                         constructor_method = ((MethodGroupExpr) ml).Methods [0];\r
 628                         return true;\r
 629                 }\r
 630 \r
 631                 protected Expression ResolveMethodGroupExpr (EmitContext ec, MethodGroupExpr mg)\r
 632                 {\r
 633                         foreach (MethodInfo mi in mg.Methods){\r
 634                                 delegate_method  = Delegate.VerifyMethod (ec, type, mi, loc);\r
 635                                 \r
 636                                 if (delegate_method != null)\r
 637                                         break;\r
 638                         }\r
 639                         \r
 640                         if (delegate_method == null) {\r
 641                                 Error_NoMatchingMethodForDelegate (mg, type, delegate_method, loc);\r
 642                                 return null;\r
 643                         }\r
 644                         \r
 645                         //\r
 646                         // Check safe/unsafe of the delegate\r
 647                         //\r
 648                         if (!ec.InUnsafe){\r
 649                                 ParameterData param = Invocation.GetParameterData (delegate_method);\r
 650                                 int count = param.Count;\r
 651                                 \r
 652                                 for (int i = 0; i < count; i++){\r
 653                                         if (param.ParameterType (i).IsPointer){\r
 654                                                 Expression.UnsafeError (loc);\r
 655                                                 return null;\r
 656                                         }\r
 657                                 }\r
 658                         }\r
 659                         \r
 660                         if (mg.InstanceExpression != null)\r
 661                                 delegate_instance_expr = mg.InstanceExpression.Resolve (ec);\r
 662                         else {\r
 663                                 if (ec.IsStatic){\r
 664                                         if (!delegate_method.IsStatic){\r
 665                                                 Report.Error (120, loc,\r
 666                                                               "An object reference is required for the non-static method " +\r
 667                                                               delegate_method.Name);\r
 668                                                 return null;\r
 669                                         }\r
 670                                         delegate_instance_expr = null;\r
 671                                 } else\r
 672                                         delegate_instance_expr = ec.GetThis (loc);\r
 673                         }\r
 674                         \r
 675                         if (delegate_instance_expr != null)\r
 676                                 if (delegate_instance_expr.Type.IsValueType)\r
 677                                         delegate_instance_expr = new BoxedCast (delegate_instance_expr);\r
 678                         \r
 679                         eclass = ExprClass.Value;\r
 680                         return this;\r
 681                 }\r
 682         }\r
 683 \r
 684         //\r
 685         // Created from the conversion code\r
 686         //\r
 687         public class ImplicitDelegateCreation : DelegateCreation {\r
 688 \r
 689                 ImplicitDelegateCreation (Type t, Location l)\r
 690                 {\r
 691                         type = t;\r
 692                         loc = l;\r
 693                 }\r
 694 \r
 695                 public override Expression DoResolve (EmitContext ec)\r
 696                 {\r
 697                         return this;\r
 698                 }\r
 699                 \r
 700                 static public Expression Create (EmitContext ec, MethodGroupExpr mge, Type target_type, Location loc)\r
 701                 {\r
 702                         ImplicitDelegateCreation d = new ImplicitDelegateCreation (target_type, loc);\r
 703                         if (d.ResolveConstructorMethod (ec))\r
 704                                 return d.ResolveMethodGroupExpr (ec, mge);\r
 705                         else\r
 706                                 return null;\r
 707                 }\r
 708         }\r
 709         \r
 710         //\r
 711         // A delegate-creation-expression, invoked from the `New' class \r
 712         //\r
 713         public class NewDelegate : DelegateCreation {\r
 714                 public ArrayList Arguments;\r
 715 \r
 716                 //\r
 717                 // This constructor is invoked from the `New' expression\r
 718                 //\r
 719                 public NewDelegate (Type type, ArrayList Arguments, Location loc)\r
 720                 {\r
 721                         this.type = type;\r
 722                         this.Arguments = Arguments;\r
 723                         this.loc  = loc; \r
 724                 }\r
 725 \r
 726                 public override Expression DoResolve (EmitContext ec)\r
 727                 {\r
 728                         if (Arguments == null || Arguments.Count != 1) {\r
 729                                 Report.Error (149, loc,\r
 730                                               "Method name expected");\r
 731                                 return null;\r
 732                         }\r
 733 \r
 734                         if (!ResolveConstructorMethod (ec))\r
 735                                 return null;\r
 736 \r
 737                         Argument a = (Argument) Arguments [0];\r
 738                         \r
 739                         Expression invoke_method = Expression.MemberLookup (\r
 740                                 ec, type, "Invoke", MemberTypes.Method,\r
 741                                 Expression.AllBindingFlags, loc);\r
 742 \r
 743                         if (invoke_method == null) {\r
 744                                 Report.Error (-200, loc, "Internal error ! Could not find Invoke method!");\r
 745                                 return null;\r
 746                         }\r
 747 \r
 748                         if (!a.ResolveMethodGroup (ec, loc))\r
 749                                 return null;\r
 750                         \r
 751                         Expression e = a.Expr;\r
 752 \r
 753                         MethodGroupExpr mg = e as MethodGroupExpr;\r
 754                         if (mg != null)\r
 755                                 return ResolveMethodGroupExpr (ec, mg);\r
 756 \r
 757                         Type e_type = e.Type;\r
 758 \r
 759                         if (!TypeManager.IsDelegateType (e_type)) {\r
 760                                 e.Error_UnexpectedKind ("method");\r
 761                                 return null;\r
 762                         }\r
 763 \r
 764                         // This is what MS' compiler reports. We could always choose\r
 765                         // to be more verbose and actually give delegate-level specifics\r
 766                         \r
 767                         if (!Delegate.VerifyDelegate (ec, type, e_type, loc)) {\r
 768                                 Report.Error (29, loc, "Cannot implicitly convert type '" + e_type + "' " +\r
 769                                               "to type '" + type + "'");\r
 770                                 return null;\r
 771                         }\r
 772                                 \r
 773                         delegate_instance_expr = e;\r
 774                         delegate_method = ((MethodGroupExpr) invoke_method).Methods [0];\r
 775                         \r
 776                         eclass = ExprClass.Value;\r
 777                         return this;\r
 778                 }\r
 779                 \r
 780                 public override void Emit (EmitContext ec)\r
 781                 {\r
 782                         if (delegate_instance_expr == null || delegate_method.IsStatic)\r
 783                                 ec.ig.Emit (OpCodes.Ldnull);\r
 784                         else\r
 785                                 delegate_instance_expr.Emit (ec);\r
 786                         \r
 787                         if (delegate_method.IsVirtual) {\r
 788                                 ec.ig.Emit (OpCodes.Dup);\r
 789                                 ec.ig.Emit (OpCodes.Ldvirtftn, (MethodInfo) delegate_method);\r
 790                         } else\r
 791                                 ec.ig.Emit (OpCodes.Ldftn, (MethodInfo) delegate_method);\r
 792                         ec.ig.Emit (OpCodes.Newobj, (ConstructorInfo) constructor_method);\r
 793                 }\r
 794         }\r
 795 \r
 796         public class DelegateInvocation : ExpressionStatement {\r
 797 \r
 798                 public Expression InstanceExpr;\r
 799                 public ArrayList  Arguments;\r
 800 \r
 801                 MethodBase method;\r
 802                 \r
 803                 public DelegateInvocation (Expression instance_expr, ArrayList args, Location loc)\r
 804                 {\r
 805                         this.InstanceExpr = instance_expr;\r
 806                         this.Arguments = args;\r
 807                         this.loc = loc;\r
 808                 }\r
 809 \r
 810                 public override Expression DoResolve (EmitContext ec)\r
 811                 {\r
 812                         if (InstanceExpr is EventExpr) {\r
 813                                 \r
 814                                 EventInfo ei = ((EventExpr) InstanceExpr).EventInfo;\r
 815                                 \r
 816                                 Expression ml = MemberLookup (\r
 817                                         ec, ec.ContainerType, ei.Name,\r
 818                                         MemberTypes.Event, AllBindingFlags | BindingFlags.DeclaredOnly, loc);\r
 819 \r
 820                                 if (ml == null) {\r
 821                                         //\r
 822                                         // If this is the case, then the Event does not belong \r
 823                                         // to this Type and so, according to the spec\r
 824                                         // cannot be accessed directly\r
 825                                         //\r
 826                                         // Note that target will not appear as an EventExpr\r
 827                                         // in the case it is being referenced within the same type container;\r
 828                                         // it will appear as a FieldExpr in that case.\r
 829                                         //\r
 830                                         \r
 831                                         Assign.error70 (ei, loc);\r
 832                                         return null;\r
 833                                 }\r
 834                         }\r
 835                         \r
 836                         \r
 837                         Type del_type = InstanceExpr.Type;\r
 838                         if (del_type == null)\r
 839                                 return null;\r
 840                         \r
 841                         if (Arguments != null){\r
 842                                 foreach (Argument a in Arguments){\r
 843                                         if (!a.Resolve (ec, loc))\r
 844                                                 return null;\r
 845                                 }\r
 846                         }\r
 847                         \r
 848                         if (!Delegate.VerifyApplicability (ec, del_type, Arguments, loc))\r
 849                                 return null;\r
 850 \r
 851                         Expression lookup = Expression.MemberLookup (ec, del_type, "Invoke", loc);\r
 852                         if (!(lookup is MethodGroupExpr)) {\r
 853                                 Report.Error (-100, loc, "Internal error: could not find Invoke method!");\r
 854                                 return null;\r
 855                         }\r
 856                         \r
 857                         method = ((MethodGroupExpr) lookup).Methods [0];\r
 858                         type = ((MethodInfo) method).ReturnType;\r
 859                         eclass = ExprClass.Value;\r
 860                         \r
 861                         return this;\r
 862                 }\r
 863 \r
 864                 public override void Emit (EmitContext ec)\r
 865                 {\r
 866                         //\r
 867                         // Invocation on delegates call the virtual Invoke member\r
 868                         // so we are always `instance' calls\r
 869                         //\r
 870                         Invocation.EmitCall (ec, false, false, InstanceExpr, method, Arguments, loc);\r
 871                 }\r
 872 \r
 873                 public override void EmitStatement (EmitContext ec)\r
 874                 {\r
 875                         Emit (ec);\r
 876                         // \r
 877                         // Pop the return value if there is one\r
 878                         //\r
 879                         if (method is MethodInfo){\r
 880                                 if (((MethodInfo) method).ReturnType != TypeManager.void_type)\r
 881                                         ec.ig.Emit (OpCodes.Pop);\r
 882                         }\r
 883                 }\r
 884 \r
 885         }\r
 886 }\r