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