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 #if MS_COMPATIBLE
 355                 //
 356                 // Workaround System.InvalidOperationException for enums
 357                 //
 358                 protected override int GetHash (object key)
 359                 {
 360                         TypeBuilder tb = key as TypeBuilder;
 361                         if (tb != null && tb.BaseType == TypeManager.enum_type)
 362                                 key = tb.BaseType;
 363
 364                         return base.GetHash (key);
 365                 }
 366 #endif
 367         }
 368
 369         /*
 370          * Hashtable whose keys are character arrays with the same length
 371          */
 372         class CharArrayHashtable : Hashtable {
 373                 sealed class ArrComparer : IComparer {
 374                         private int len;
 375
 376                         public ArrComparer (int len) {
 377                                 this.len = len;
 378                         }
 379
 380                         public int Compare (object x, object y)
 381                         {
 382                                 char[] a = (char[])x;
 383                                 char[] b = (char[])y;
 384
 385                                 for (int i = 0; i < len; ++i)
 386                                         if (a [i] != b [i])
 387                                                 return 1;
 388                                 return 0;
 389                         }
 390                 }
 391
 392                 private int len;
 393
 394                 protected override int GetHash (Object key)
 395                 {
 396                         char[] arr = (char[])key;
 397                         int h = 0;
 398
 399                         for (int i = 0; i < len; ++i)
 400                                 h = (h << 5) - h + arr [i];
 401
 402                         return h;
 403                 }
 404
 405                 public CharArrayHashtable (int len)
 406                 {
 407                         this.len = len;
 408                         comparer = new ArrComparer (len);
 409                 }
 410         }
 411
 412         struct Pair {
 413                 public object First;
 414                 public object Second;
 415
 416                 public Pair (object f, object s)
 417                 {
 418                         First = f;
 419                         Second = s;
 420                 }
 421         }
 422
 423         public class Accessors {
 424                 public Accessor get_or_add;
 425                 public Accessor set_or_remove;
 426
 427                 // was 'set' declared before 'get'?  was 'remove' declared before 'add'?
 428                 public bool declared_in_reverse;
 429
 430                 public Accessors (Accessor get_or_add, Accessor set_or_remove)
 431                 {
 432                         this.get_or_add = get_or_add;
 433                         this.set_or_remove = set_or_remove;
 434                 }
 435         }
 436
 437         /// <summary>
 438         ///   This is a wrapper around StreamReader which is seekable backwards
 439         ///   within a window of around 2048 chars.
 440         /// </summary>
 441         public class SeekableStreamReader
 442         {
 443                 const int AverageReadLength = 1024;
 444                 TextReader reader;
 445                 Stream stream;
 446                 Encoding encoding;
 447
 448                 char[] buffer;
 449                 int buffer_start;       // in chars
 450                 int char_count;         // count buffer[] valid characters
 451                 int pos;                // index into buffer[]
 452
 453                 public SeekableStreamReader (Stream stream, Encoding encoding)
 454                 {
 455                         this.stream = stream;
 456                         this.encoding = encoding;
 457
 458                         this.reader = new StreamReader (stream, encoding, true);
 459                         this.buffer = new char [AverageReadLength * 3];
 460
 461                         // Let the StreamWriter autodetect the encoder
 462                         reader.Peek ();
 463                 }
 464
 465                 /// <remarks>
 466                 ///   This value corresponds to the current position in a stream of characters.
 467                 ///   The StreamReader hides its manipulation of the underlying byte stream and all
 468                 ///   character set/decoding issues.  Thus, we cannot use this position to guess at
 469                 ///   the corresponding position in the underlying byte stream even though there is
 470                 ///   a correlation between them.
 471                 /// </remarks>
 472                 public int Position {
 473                         get { return buffer_start + pos; }
 474
 475                         set {
 476                                 if (value > buffer_start + char_count)
 477                                         throw new InternalErrorException ("can't seek that far forward: " + (pos - value));
 478
 479                                 if (value < buffer_start){
 480                                         // Reinitialize.
 481                                         stream.Position = 0;
 482                                         reader = new StreamReader (stream, encoding, true);
 483                                         buffer_start = 0;
 484                                         char_count = 0;
 485                                         pos = 0;
 486                                         Peek ();
 487
 488                                         while (value > buffer_start + char_count){
 489                                                 pos = char_count+1;
 490                                                 Peek ();
 491                                         }
 492                                         pos = value - buffer_start;
 493                                 }
 494
 495                                 pos = value - buffer_start;
 496                         }
 497                 }
 498
 499                 private bool ReadBuffer ()
 500                 {
 501                         int slack = buffer.Length - char_count;
 502                         if (slack <= AverageReadLength / 2) {
 503                                 // shift the buffer to make room for AverageReadLength number of characters
 504                                 int shift = AverageReadLength - slack;
 505                                 Array.Copy (buffer, shift, buffer, 0, char_count - shift);
 506                                 pos -= shift;
 507                                 char_count -= shift;
 508                                 buffer_start += shift;
 509                                 slack += shift;         // slack == AverageReadLength
 510                         }
 511
 512                         int chars_read = reader.Read (buffer, char_count, slack);
 513                         char_count += chars_read;
 514
 515                         return pos < char_count;
 516                 }
 517
 518                 public int Peek ()
 519                 {
 520                         if ((pos >= char_count) && !ReadBuffer ())
 521                                 return -1;
 522
 523                         return buffer [pos];
 524                 }
 525
 526                 public int Read ()
 527                 {
 528                         if ((pos >= char_count) && !ReadBuffer ())
 529                                 return -1;
 530
 531                         return buffer [pos++];
 532                 }
 533         }
 534
 535         public class DoubleHash {
 536                 const int DEFAULT_INITIAL_BUCKETS = 100;
 537
 538                 public DoubleHash () : this (DEFAULT_INITIAL_BUCKETS) {}
 539
 540                 public DoubleHash (int size)
 541                 {
 542                         count = size;
 543                         buckets = new Entry [size];
 544                 }
 545
 546                 int count;
 547                 Entry [] buckets;
 548                 int size = 0;
 549
 550                 class Entry {
 551                         public object key1;
 552                         public object key2;
 553                         public int hash;
 554                         public object value;
 555                         public Entry next;
 556
 557                         public Entry (object key1, object key2, int hash, object value, Entry next)
 558                         {
 559                                 this.key1 = key1;
 560                                 this.key2 = key2;
 561                                 this.hash = hash;
 562                                 this.next = next;
 563                                 this.value = value;
 564                         }
 565                 }
 566
 567                 public bool Lookup (object a, object b, out object res)
 568                 {
 569                         int h = (a.GetHashCode () ^ b.GetHashCode ()) & 0x7FFFFFFF;
 570
 571                         for (Entry e = buckets [h % count]; e != null; e = e.next) {
 572                                 if (e.hash == h && e.key1.Equals (a) && e.key2.Equals (b)) {
 573                                         res = e.value;
 574                                         return true;
 575                                 }
 576                         }
 577                         res = null;
 578                         return false;
 579                 }
 580
 581                 public void Insert (object a, object b, object value)
 582                 {
 583                         // Is it an existing one?
 584
 585                         int h = (a.GetHashCode () ^ b.GetHashCode ()) & 0x7FFFFFFF;
 586
 587                         for (Entry e = buckets [h % count]; e != null; e = e.next) {
 588                                 if (e.hash == h && e.key1.Equals (a) && e.key2.Equals (b))
 589                                         e.value = value;
 590                         }
 591
 592                         int bucket = h % count;
 593                         buckets [bucket] = new Entry (a, b, h, value, buckets [bucket]);
 594
 595                         // Grow whenever we double in size
 596                         if (size++ == count) {
 597                                 count <<= 1;
 598                                 count ++;
 599
 600                                 Entry [] newBuckets = new Entry [count];
 601                                 foreach (Entry root in buckets) {
 602                                         Entry e = root;
 603                                         while (e != null) {
 604                                                 int newLoc = e.hash % count;
 605                                                 Entry n = e.next;
 606                                                 e.next = newBuckets [newLoc];
 607                                                 newBuckets [newLoc] = e;
 608                                                 e = n;
 609                                         }
 610                                 }
 611
 612                                 buckets = newBuckets;
 613                         }
 614                 }
 615         }
 616
 617         class PartialMethodDefinitionInfo : MethodInfo
 618         {
 619                 MethodOrOperator mc;
 620                 MethodAttributes attrs;
 621
 622                 public PartialMethodDefinitionInfo (MethodOrOperator mc)
 623                 {
 624                         this.mc = mc;
 625                         if ((mc.ModFlags & Modifiers.STATIC) != 0)
 626                                 attrs = MethodAttributes.Static;
 627                 }
 628
 629                 public override MethodInfo GetBaseDefinition ()
 630                 {
 631                         throw new NotImplementedException ();
 632                 }
 633
 634                 public override ICustomAttributeProvider ReturnTypeCustomAttributes
 635                 {
 636                         get { throw new NotImplementedException (); }
 637                 }
 638
 639                 public override MethodAttributes Attributes
 640                 {
 641                         get { return attrs; }
 642                 }
 643
 644                 public override MethodImplAttributes GetMethodImplementationFlags ()
 645                 {
 646                         throw new NotImplementedException ();
 647                 }
 648
 649                 public override ParameterInfo [] GetParameters ()
 650                 {
 651                         throw new NotImplementedException ();
 652                 }
 653
 654                 public override object Invoke (object obj, BindingFlags invokeAttr, Binder binder, object [] parameters, CultureInfo culture)
 655                 {
 656                         throw new NotImplementedException ();
 657                 }
 658
 659                 public override RuntimeMethodHandle MethodHandle
 660                 {
 661                         get { throw new NotImplementedException (); }
 662                 }
 663
 664                 public override Type DeclaringType
 665                 {
 666                         get { return mc.Parent.TypeBuilder; }
 667                 }
 668
 669                 public override object [] GetCustomAttributes (Type attributeType, bool inherit)
 670                 {
 671                         throw new NotImplementedException ();
 672                 }
 673
 674                 public override object [] GetCustomAttributes (bool inherit)
 675                 {
 676                         throw new NotImplementedException ();
 677                 }
 678
 679                 public override Type ReturnType {
 680                         get {
 681                                 return mc.MemberType;
 682                         }
 683                 }
 684
 685                 public override bool IsDefined (Type attributeType, bool inherit)
 686                 {
 687                         throw new NotImplementedException ();
 688                 }
 689
 690                 public override string Name
 691                 {
 692                         get { return mc.Name; }
 693                 }
 694
 695                 public override Type ReflectedType
 696                 {
 697                         get { throw new NotImplementedException (); }
 698                 }
 699         }
 700
 701 }