mcs/mcs/support.cs

   1 //
   2 // support.cs: Support routines to work around the fact that System.Reflection.Emit
   3 // can not introspect types that are being constructed
   4 //
   5 // Author:
   6 //   Miguel de Icaza (miguel@ximian.com)
   7 //
   8 // Copyright 2001 Ximian, Inc (http://www.ximian.com)
   9 // Copyright 2003-2008 Novell, Inc
  10 //
  11
  12 using System;
  13 using System.IO;
  14 using System.Text;
  15 using System.Reflection;
  16 using System.Collections;
  17 using System.Reflection.Emit;
  18 using System.Globalization;
  19
  20 namespace Mono.CSharp {
  21
  22         public interface ParameterData {
  23                 Type ParameterType (int pos);
  24                 Type [] Types { get; }
  25                 int  Count { get; }
  26                 Type ExtensionMethodType { get; }
  27                 bool HasParams { get; }
  28                 string ParameterName (int pos);
  29                 string ParameterDesc (int pos);
  30
  31                 Parameter.Modifier ParameterModifier (int pos);
  32                 string GetSignatureForError ();
  33
  34 #if MS_COMPATIBLE
  35                 ParameterData InflateTypes (Type[] genArguments, Type[] argTypes);
  36 #endif
  37         }
  38
  39         public class ReflectionParameters : ParameterData {
  40                 ParameterInfo [] pi;
  41                 Type [] types;
  42                 int params_idx = int.MaxValue;
  43                 bool is_varargs;
  44                 bool is_extension;
  45                 ParameterData gpd;
  46
  47                 public ReflectionParameters (MethodBase mb)
  48                 {
  49                         ParameterInfo [] pi = mb.GetParameters ();
  50                         is_varargs = (mb.CallingConvention & CallingConventions.VarArgs) != 0;
  51
  52                         this.pi = pi;
  53                         int count = pi.Length;
  54
  55                         if (count == 0) {
  56                                 types = Type.EmptyTypes;
  57                                 return;
  58                         }
  59
  60                         types = new Type [count];
  61                         for (int i = 0; i < count; i++)
  62                                 types [i] = TypeManager.TypeToCoreType (pi [i].ParameterType);
  63
  64                         // TODO: This (if) should be done one level higher to correctly use
  65                         // out caching facilities.
  66                         MethodBase generic = TypeManager.DropGenericMethodArguments (mb);
  67                         if (generic != mb) {
  68                                 gpd = TypeManager.GetParameterData (generic);
  69                                 if (gpd.HasParams) {
  70                                         for (int i = gpd.Count; i != 0; --i) {
  71                                                 if ((gpd.ParameterModifier (i-1) & Parameter.Modifier.PARAMS) != 0) {
  72                                                         this.params_idx = i-1;
  73                                                         break;
  74                                                 }
  75                                         }
  76                                 }
  77                                 return;
  78                         }
  79
  80                         //
  81                         // So far, the params attribute can be used in C# for the last
  82                         // and next to last method parameters.
  83                         // If some other language can place it anywhere we will
  84                         // have to analyze all parameters and not just last 2.
  85                         //
  86                         --count;
  87                         for (int i = count; i >= 0 && i > count - 2; --i) {
  88                                 if (!pi [i].ParameterType.IsArray)
  89                                         continue;
  90
  91                                 if (pi [i].IsDefined (TypeManager.param_array_type, false)) {
  92                                         params_idx = i;
  93                                         break;
  94                                 }
  95                         }
  96
  97                         if (TypeManager.extension_attribute_type != null && mb.IsStatic &&
  98                                 (mb.DeclaringType.Attributes & Class.StaticClassAttribute) == Class.StaticClassAttribute &&
  99                                 mb.IsDefined (TypeManager.extension_attribute_type, false))
 100                                 is_extension = true;
 101                 }
 102
 103                 public override bool Equals (object obj)
 104                 {
 105                         ReflectionParameters rp = obj as ReflectionParameters;
 106                         if (rp == null)
 107                                 return false;
 108
 109                         if (Count != rp.Count)
 110                                 return false;
 111
 112                         for (int i = 0; i < Count; ++i) {
 113                         if (!types [i].Equals (rp.types [i]))
 114                                 return false;
 115                         }
 116                         return true;
 117                 }
 118
 119                 public override int GetHashCode ()
 120                 {
 121                         return base.GetHashCode ();
 122                 }
 123
 124                 public string GetSignatureForError ()
 125                 {
 126                         StringBuilder sb = new StringBuilder ("(");
 127                         for (int i = 0; i < pi.Length; ++i) {
 128                                 if (i != 0)
 129                                         sb.Append (", ");
 130                                 sb.Append (ParameterDesc (i));
 131                         }
 132                         if (is_varargs) {
 133                                 if (pi.Length > 0)
 134                                         sb.Append (", ");
 135                                 sb.Append ("__arglist");
 136                         }
 137                         sb.Append (')');
 138                         return sb.ToString ();
 139                 }
 140
 141 #if MS_COMPATIBLE
 142                 public ParameterData InflateTypes (Type[] genArguments, Type[] argTypes)
 143                 {
 144                         ReflectionParameters p = (ReflectionParameters)MemberwiseClone ();
 145
 146                         for (int i = 0; i < types.Length; ++i) {
 147                                 if (types[i].IsGenericParameter) {
 148                                         for (int ii = 0; ii < genArguments.Length; ++ii) {
 149                                                 if (types[i] != genArguments[ii])
 150                                                         continue;
 151
 152                                                 p.types[i] = argTypes[ii];
 153                                                 break;
 154                                         }
 155                                         continue;
 156                                 }
 157
 158                                 if (types[i].IsGenericType) {
 159                                         Type[] gen_arguments_open = types[i].GetGenericTypeDefinition ().GetGenericArguments ();
 160                                         Type[] gen_arguments = types[i].GetGenericArguments ();
 161                                         for (int ii = 0; ii < gen_arguments_open.Length; ++ii) {
 162                                                 if (gen_arguments [ii].IsGenericParameter) {
 163                                                         for (int iii = 0; iii < genArguments.Length; ++iii) {
 164                                                                 if (gen_arguments [ii] != genArguments [iii])
 165                                                                         continue;
 166
 167                                                                 gen_arguments_open [ii] = argTypes [iii];
 168                                                                 break;
 169                                                         }
 170                                                 } else {
 171                                                         gen_arguments_open [ii] = gen_arguments [ii];
 172                                                 }
 173                                         }
 174
 175                                         p.types[i] = types[i].GetGenericTypeDefinition ().MakeGenericType (gen_arguments_open);
 176                                 }
 177                         }
 178                         return p;
 179                 }
 180 #endif
 181
 182                 public Type ParameterType (int pos)
 183                 {
 184                         if (is_varargs && pos >= pi.Length)
 185                                 return TypeManager.runtime_argument_handle_type;
 186
 187                         return types [pos];
 188                 }
 189
 190                 public string ParameterName (int pos)
 191                 {
 192                         if (gpd != null)
 193                                 return gpd.ParameterName (pos);
 194
 195                         if (is_varargs && pos >= pi.Length)
 196                                 return "__arglist";
 197
 198                         return pi [pos].Name;
 199                 }
 200
 201                 public string ParameterDesc (int pos)
 202                 {
 203                         if (is_varargs && pos >= pi.Length)
 204                                 return "";
 205
 206                         StringBuilder sb = new StringBuilder ();
 207
 208                         if (pi [pos].IsIn)
 209                                 sb.Append ("in ");
 210
 211                         Type partype = ParameterType (pos);
 212                         if (partype.IsByRef){
 213                                 partype = TypeManager.GetElementType (partype);
 214                                 if (pi [pos].IsOut)
 215                                         sb.Append ("out ");
 216                                 else
 217                                         sb.Append ("ref ");
 218                         }
 219
 220                         if (params_idx == pos)
 221                                 sb.Append ("params ");
 222
 223                         if (pos == 0 && ExtensionMethodType != null)
 224                                 sb.Append ("this ");
 225
 226                         sb.Append (TypeManager.CSharpName (partype).Replace ("&", ""));
 227
 228                         return sb.ToString ();
 229                 }
 230
 231                 public Parameter.Modifier ParameterModifier (int pos)
 232                 {
 233                         if (pos >= params_idx)
 234                                 return Parameter.Modifier.PARAMS;
 235                         if (is_varargs && pos >= pi.Length)
 236                                 return Parameter.Modifier.ARGLIST;
 237
 238                         if (gpd != null)
 239                                 return gpd.ParameterModifier (pos);
 240
 241                         Type t = types [pos];
 242                         if (t.IsByRef){
 243                                 if ((pi [pos].Attributes & (ParameterAttributes.Out|ParameterAttributes.In)) == ParameterAttributes.Out)
 244                                         return Parameter.Modifier.OUT;
 245                                 else
 246                                         return Parameter.Modifier.REF;
 247                         }
 248
 249                         return Parameter.Modifier.NONE;
 250                 }
 251
 252                 public int Count {
 253                         get { return is_varargs ? pi.Length + 1 : pi.Length; }
 254                 }
 255
 256                 public Type ExtensionMethodType {
 257                         get {
 258                                 if (!is_extension)
 259                                         return null;
 260
 261                                 return types [0];
 262                         }
 263                 }
 264
 265                 public bool HasParams {
 266                         get { return params_idx != int.MaxValue; }
 267                 }
 268
 269                 public Type[] Types {
 270                         get { return types; }
 271                 }
 272         }
 273
 274 #if GMCS_SOURCE
 275         public class ReflectionConstraints : GenericConstraints
 276         {
 277                 GenericParameterAttributes attrs;
 278                 Type base_type;
 279                 Type class_constraint;
 280                 Type[] iface_constraints;
 281                 string name;
 282
 283                 public static GenericConstraints GetConstraints (Type t)
 284                 {
 285                         Type [] constraints = t.GetGenericParameterConstraints ();
 286                         GenericParameterAttributes attrs = t.GenericParameterAttributes;
 287                         if (constraints.Length == 0 && attrs == GenericParameterAttributes.None)
 288                                 return null;
 289                         return new ReflectionConstraints (t.Name, constraints, attrs);
 290                 }
 291
 292                 private ReflectionConstraints (string name, Type [] constraints, GenericParameterAttributes attrs)
 293                 {
 294                         this.name = name;
 295                         this.attrs = attrs;
 296
 297                         if ((constraints.Length > 0) && !constraints [0].IsInterface) {
 298                                 class_constraint = constraints [0];
 299                                 iface_constraints = new Type [constraints.Length - 1];
 300                                 Array.Copy (constraints, 1, iface_constraints, 0, constraints.Length - 1);
 301                         } else
 302                                 iface_constraints = constraints;
 303
 304                         if (HasValueTypeConstraint)
 305                                 base_type = TypeManager.value_type;
 306                         else if (class_constraint != null)
 307                                 base_type = class_constraint;
 308                         else
 309                                 base_type = TypeManager.object_type;
 310                 }
 311
 312                 public override string TypeParameter {
 313                         get { return name; }
 314                 }
 315
 316                 public override GenericParameterAttributes Attributes {
 317                         get { return attrs; }
 318                 }
 319
 320                 public override Type ClassConstraint {
 321                         get { return class_constraint; }
 322                 }
 323
 324                 public override Type EffectiveBaseClass {
 325                         get { return base_type; }
 326                 }
 327
 328                 public override Type[] InterfaceConstraints {
 329                         get { return iface_constraints; }
 330                 }
 331         }
 332 #endif
 333
 334         class PtrHashtable : Hashtable {
 335                 sealed class PtrComparer : IComparer {
 336                         private PtrComparer () {}
 337
 338                         public static PtrComparer Instance = new PtrComparer ();
 339
 340                         public int Compare (object x, object y)
 341                         {
 342                                 if (x == y)
 343                                         return 0;
 344                                 else
 345                                         return 1;
 346                         }
 347                 }
 348
 349                 public PtrHashtable ()
 350                 {
 351                         comparer = PtrComparer.Instance;
 352                 }
 353         }
 354
 355         /*
 356          * Hashtable whose keys are character arrays with the same length
 357          */
 358         class CharArrayHashtable : Hashtable {
 359                 sealed class ArrComparer : IComparer {
 360                         private int len;
 361
 362                         public ArrComparer (int len) {
 363                                 this.len = len;
 364                         }
 365
 366                         public int Compare (object x, object y)
 367                         {
 368                                 char[] a = (char[])x;
 369                                 char[] b = (char[])y;
 370
 371                                 for (int i = 0; i < len; ++i)
 372                                         if (a [i] != b [i])
 373                                                 return 1;
 374                                 return 0;
 375                         }
 376                 }
 377
 378                 private int len;
 379
 380                 protected override int GetHash (Object key)
 381                 {
 382                         char[] arr = (char[])key;
 383                         int h = 0;
 384
 385                         for (int i = 0; i < len; ++i)
 386                                 h = (h << 5) - h + arr [i];
 387
 388                         return h;
 389                 }
 390
 391                 public CharArrayHashtable (int len)
 392                 {
 393                         this.len = len;
 394                         comparer = new ArrComparer (len);
 395                 }
 396         }
 397
 398         struct Pair {
 399                 public object First;
 400                 public object Second;
 401
 402                 public Pair (object f, object s)
 403                 {
 404                         First = f;
 405                         Second = s;
 406                 }
 407         }
 408
 409         public class Accessors {
 410                 public Accessor get_or_add;
 411                 public Accessor set_or_remove;
 412
 413                 // was 'set' declared before 'get'?  was 'remove' declared before 'add'?
 414                 public bool declared_in_reverse;
 415
 416                 public Accessors (Accessor get_or_add, Accessor set_or_remove)
 417                 {
 418                         this.get_or_add = get_or_add;
 419                         this.set_or_remove = set_or_remove;
 420                 }
 421         }
 422
 423         /// <summary>
 424         ///   This is a wrapper around StreamReader which is seekable backwards
 425         ///   within a window of around 2048 chars.
 426         /// </summary>
 427         public class SeekableStreamReader
 428         {
 429                 const int AverageReadLength = 1024;
 430                 TextReader reader;
 431                 Stream stream;
 432                 Encoding encoding;
 433
 434                 char[] buffer;
 435                 int buffer_start;       // in chars
 436                 int char_count;         // count buffer[] valid characters
 437                 int pos;                // index into buffer[]
 438
 439                 public SeekableStreamReader (Stream stream, Encoding encoding)
 440                 {
 441                         this.stream = stream;
 442                         this.encoding = encoding;
 443
 444                         this.reader = new StreamReader (stream, encoding, true);
 445                         this.buffer = new char [AverageReadLength * 3];
 446
 447                         // Let the StreamWriter autodetect the encoder
 448                         reader.Peek ();
 449                 }
 450
 451                 /// <remarks>
 452                 ///   This value corresponds to the current position in a stream of characters.
 453                 ///   The StreamReader hides its manipulation of the underlying byte stream and all
 454                 ///   character set/decoding issues.  Thus, we cannot use this position to guess at
 455                 ///   the corresponding position in the underlying byte stream even though there is
 456                 ///   a correlation between them.
 457                 /// </remarks>
 458                 public int Position {
 459                         get { return buffer_start + pos; }
 460
 461                         set {
 462                                 if (value > buffer_start + char_count)
 463                                         throw new InternalErrorException ("can't seek that far forward: " + (pos - value));
 464
 465                                 if (value < buffer_start){
 466                                         // Reinitialize.
 467                                         stream.Position = 0;
 468                                         reader = new StreamReader (stream, encoding, true);
 469                                         buffer_start = 0;
 470                                         char_count = 0;
 471                                         pos = 0;
 472                                         Peek ();
 473
 474                                         while (value > buffer_start + char_count){
 475                                                 pos = char_count+1;
 476                                                 Peek ();
 477                                         }
 478                                         pos = value - buffer_start;
 479                                 }
 480
 481                                 pos = value - buffer_start;
 482                         }
 483                 }
 484
 485                 private bool ReadBuffer ()
 486                 {
 487                         int slack = buffer.Length - char_count;
 488                         if (slack <= AverageReadLength / 2) {
 489                                 // shift the buffer to make room for AverageReadLength number of characters
 490                                 int shift = AverageReadLength - slack;
 491                                 Array.Copy (buffer, shift, buffer, 0, char_count - shift);
 492                                 pos -= shift;
 493                                 char_count -= shift;
 494                                 buffer_start += shift;
 495                                 slack += shift;         // slack == AverageReadLength
 496                         }
 497
 498                         int chars_read = reader.Read (buffer, char_count, slack);
 499                         char_count += chars_read;
 500
 501                         return pos < char_count;
 502                 }
 503
 504                 public int Peek ()
 505                 {
 506                         if ((pos >= char_count) && !ReadBuffer ())
 507                                 return -1;
 508
 509                         return buffer [pos];
 510                 }
 511
 512                 public int Read ()
 513                 {
 514                         if ((pos >= char_count) && !ReadBuffer ())
 515                                 return -1;
 516
 517                         return buffer [pos++];
 518                 }
 519         }
 520
 521         public class DoubleHash {
 522                 const int DEFAULT_INITIAL_BUCKETS = 100;
 523
 524                 public DoubleHash () : this (DEFAULT_INITIAL_BUCKETS) {}
 525
 526                 public DoubleHash (int size)
 527                 {
 528                         count = size;
 529                         buckets = new Entry [size];
 530                 }
 531
 532                 int count;
 533                 Entry [] buckets;
 534                 int size = 0;
 535
 536                 class Entry {
 537                         public object key1;
 538                         public object key2;
 539                         public int hash;
 540                         public object value;
 541                         public Entry next;
 542
 543                         public Entry (object key1, object key2, int hash, object value, Entry next)
 544                         {
 545                                 this.key1 = key1;
 546                                 this.key2 = key2;
 547                                 this.hash = hash;
 548                                 this.next = next;
 549                                 this.value = value;
 550                         }
 551                 }
 552
 553                 public bool Lookup (object a, object b, out object res)
 554                 {
 555                         int h = (a.GetHashCode () ^ b.GetHashCode ()) & 0x7FFFFFFF;
 556
 557                         for (Entry e = buckets [h % count]; e != null; e = e.next) {
 558                                 if (e.hash == h && e.key1.Equals (a) && e.key2.Equals (b)) {
 559                                         res = e.value;
 560                                         return true;
 561                                 }
 562                         }
 563                         res = null;
 564                         return false;
 565                 }
 566
 567                 public void Insert (object a, object b, object value)
 568                 {
 569                         // Is it an existing one?
 570
 571                         int h = (a.GetHashCode () ^ b.GetHashCode ()) & 0x7FFFFFFF;
 572
 573                         for (Entry e = buckets [h % count]; e != null; e = e.next) {
 574                                 if (e.hash == h && e.key1.Equals (a) && e.key2.Equals (b))
 575                                         e.value = value;
 576                         }
 577
 578                         int bucket = h % count;
 579                         buckets [bucket] = new Entry (a, b, h, value, buckets [bucket]);
 580
 581                         // Grow whenever we double in size
 582                         if (size++ == count) {
 583                                 count <<= 1;
 584                                 count ++;
 585
 586                                 Entry [] newBuckets = new Entry [count];
 587                                 foreach (Entry root in buckets) {
 588                                         Entry e = root;
 589                                         while (e != null) {
 590                                                 int newLoc = e.hash % count;
 591                                                 Entry n = e.next;
 592                                                 e.next = newBuckets [newLoc];
 593                                                 newBuckets [newLoc] = e;
 594                                                 e = n;
 595                                         }
 596                                 }
 597
 598                                 buckets = newBuckets;
 599                         }
 600                 }
 601         }
 602
 603         class PartialMethodDefinitionInfo : MethodInfo
 604         {
 605                 MethodOrOperator mc;
 606                 MethodAttributes attrs;
 607
 608                 public PartialMethodDefinitionInfo (MethodOrOperator mc)
 609                 {
 610                         this.mc = mc;
 611                         if ((mc.ModFlags & Modifiers.STATIC) != 0)
 612                                 attrs = MethodAttributes.Static;
 613                 }
 614
 615                 public override MethodInfo GetBaseDefinition ()
 616                 {
 617                         throw new NotImplementedException ();
 618                 }
 619
 620                 public override ICustomAttributeProvider ReturnTypeCustomAttributes
 621                 {
 622                         get { throw new NotImplementedException (); }
 623                 }
 624
 625                 public override MethodAttributes Attributes
 626                 {
 627                         get { return attrs; }
 628                 }
 629
 630                 public override MethodImplAttributes GetMethodImplementationFlags ()
 631                 {
 632                         throw new NotImplementedException ();
 633                 }
 634
 635                 public override ParameterInfo [] GetParameters ()
 636                 {
 637                         throw new NotImplementedException ();
 638                 }
 639
 640                 public override object Invoke (object obj, BindingFlags invokeAttr, Binder binder, object [] parameters, CultureInfo culture)
 641                 {
 642                         throw new NotImplementedException ();
 643                 }
 644
 645                 public override RuntimeMethodHandle MethodHandle
 646                 {
 647                         get { throw new NotImplementedException (); }
 648                 }
 649
 650                 public override Type DeclaringType
 651                 {
 652                         get { return mc.Parent.TypeBuilder; }
 653                 }
 654
 655                 public override object [] GetCustomAttributes (Type attributeType, bool inherit)
 656                 {
 657                         throw new NotImplementedException ();
 658                 }
 659
 660                 public override object [] GetCustomAttributes (bool inherit)
 661                 {
 662                         throw new NotImplementedException ();
 663                 }
 664
 665                 public override Type ReturnType {
 666                         get {
 667                                 return mc.MemberType;
 668                         }
 669                 }
 670
 671                 public override bool IsDefined (Type attributeType, bool inherit)
 672                 {
 673                         throw new NotImplementedException ();
 674                 }
 675
 676                 public override string Name
 677                 {
 678                         get { return mc.Name; }
 679                 }
 680
 681                 public override Type ReflectedType
 682                 {
 683                         get { throw new NotImplementedException (); }
 684                 }
 685         }
 686
 687 }