UnknownFieldSet.cs 26.9 KB
Newer Older
1
#region Copyright notice and license
Jon Skeet's avatar
Jon Skeet committed
2 3 4 5
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// http://github.com/jskeet/dotnet-protobufs/
// Original C++/Java/Python code:
Jon Skeet's avatar
Jon Skeet committed
6 7
// http://code.google.com/p/protobuf/
//
Jon Skeet's avatar
Jon Skeet committed
8 9 10
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
Jon Skeet's avatar
Jon Skeet committed
11
//
Jon Skeet's avatar
Jon Skeet committed
12 13 14 15 16 17 18 19 20
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
Jon Skeet's avatar
Jon Skeet committed
21
//
Jon Skeet's avatar
Jon Skeet committed
22 23 24 25 26 27 28 29 30 31 32
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 34
#endregion

Jon Skeet's avatar
Jon Skeet committed
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
using System;
using System.Collections.Generic;
using System.IO;
using Google.ProtocolBuffers.Collections;
using Google.ProtocolBuffers.Descriptors;
using Google.ProtocolBuffers.DescriptorProtos;

namespace Google.ProtocolBuffers {
  /// <summary>
  /// Used to keep track of fields which were seen when parsing a protocol message
  /// but whose field numbers or types are unrecognized. This most frequently
  /// occurs when new fields are added to a message type and then messages containing
  /// those fields are read by old software that was built before the new types were
  /// added.
  /// 
  /// Every message contains an UnknownFieldSet.
  /// 
  /// Most users will never need to use this class directly.
  /// </summary>
54
  public sealed class UnknownFieldSet : IMessageLite {
Jon Skeet's avatar
Jon Skeet committed
55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199

    private static readonly UnknownFieldSet defaultInstance = new UnknownFieldSet(new Dictionary<int, UnknownField>());

    private readonly IDictionary<int, UnknownField> fields;

    private UnknownFieldSet(IDictionary<int, UnknownField> fields) {
      this.fields = fields;
    }

    /// <summary>
    /// Creates a new unknown field set builder.
    /// </summary>
    public static Builder CreateBuilder() {
      return new Builder();
    }

    /// <summary>
    /// Creates a new unknown field set builder 
    /// and initialize it from <paramref name="original"/>.
    /// </summary>
    public static Builder CreateBuilder(UnknownFieldSet original) {
      return new Builder().MergeFrom(original);
    }

    public static UnknownFieldSet DefaultInstance {
      get { return defaultInstance; }
    }

    /// <summary>
    /// Returns a read-only view of the mapping from field numbers to values.
    /// </summary>
    public IDictionary<int, UnknownField> FieldDictionary {
      get { return Dictionaries.AsReadOnly(fields); }
    }

    /// <summary>
    /// Checks whether or not the given field number is present in the set.
    /// </summary>
    public bool HasField(int field) {
      return fields.ContainsKey(field);
    }

    /// <summary>
    /// Fetches a field by number, returning an empty field if not present.
    /// Never returns null.
    /// </summary>
    public UnknownField this[int number] {
      get {
        UnknownField ret;
        if (!fields.TryGetValue(number, out ret)) {
          ret = UnknownField.DefaultInstance;
        }
        return ret;
      }
    }

    /// <summary>
    /// Serializes the set and writes it to <paramref name="output"/>.
    /// </summary>
    public void WriteTo(CodedOutputStream output) {
      foreach (KeyValuePair<int, UnknownField> entry in fields) {
        entry.Value.WriteTo(entry.Key, output);
      }
    }

    /// <summary>
    /// Gets the number of bytes required to encode this set.
    /// </summary>
    public int SerializedSize { 
      get {
        int result = 0;
        foreach (KeyValuePair<int, UnknownField> entry in fields) {
          result += entry.Value.GetSerializedSize(entry.Key);
        }
        return result;
      } 
    }

    /// <summary>
    /// Converts the set to a string in protocol buffer text format. This
    /// is just a trivial wrapper around TextFormat.PrintToString.
    /// </summary>
    public override String ToString() {
      return TextFormat.PrintToString(this);
    }

    /// <summary>
    /// Serializes the message to a ByteString and returns it. This is
    /// just a trivial wrapper around WriteTo(CodedOutputStream).
    /// </summary>
    /// <returns></returns>
    public ByteString ToByteString() {
      ByteString.CodedBuilder codedBuilder = new ByteString.CodedBuilder(SerializedSize);
      WriteTo(codedBuilder.CodedOutput);
      return codedBuilder.Build();
    }

    /// <summary>
    /// Serializes the message to a byte array and returns it. This is
    /// just a trivial wrapper around WriteTo(CodedOutputStream).
    /// </summary>
    /// <returns></returns>
    public byte[] ToByteArray() {
      byte[] data = new byte[SerializedSize];
      CodedOutputStream output = CodedOutputStream.CreateInstance(data);
      WriteTo(output);
      output.CheckNoSpaceLeft();
      return data;
    }

    /// <summary>
    /// Serializes the message and writes it to <paramref name="output"/>. This is
    /// just a trivial wrapper around WriteTo(CodedOutputStream).
    /// </summary>
    /// <param name="output"></param>
    public void WriteTo(Stream output) {
      CodedOutputStream codedOutput = CodedOutputStream.CreateInstance(output);
      WriteTo(codedOutput);
      codedOutput.Flush();
    }

    /// <summary>
    /// Serializes the set and writes it to <paramref name="output"/> using
    /// the MessageSet wire format.
    /// </summary>
    public void WriteAsMessageSetTo(CodedOutputStream output) {
      foreach (KeyValuePair<int, UnknownField> entry in fields) {
        entry.Value.WriteAsMessageSetExtensionTo(entry.Key, output);
      }
    }

    /// <summary>
    /// Gets the number of bytes required to encode this set using the MessageSet
    /// wire format.
    /// </summary>
    public int SerializedSizeAsMessageSet {
      get {
        int result = 0;
        foreach (KeyValuePair<int, UnknownField> entry in fields) {
          result += entry.Value.GetSerializedSizeAsMessageSetExtension(entry.Key);
        }
        return result;
      }
    }

200 201 202 203 204 205 206 207 208 209 210 211
    public override bool Equals(object other) {
      if (ReferenceEquals(this, other)) {
        return true;
      }
      UnknownFieldSet otherSet = other as UnknownFieldSet;
      return otherSet != null && Dictionaries.Equals(fields, otherSet.fields);
    }

    public override int GetHashCode() {
      return Dictionaries.GetHashCode(fields);
    }

Jon Skeet's avatar
Jon Skeet committed
212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239
    /// <summary>
    /// Parses an UnknownFieldSet from the given input.
    /// </summary>
    public static UnknownFieldSet ParseFrom(CodedInputStream input) {
      return CreateBuilder().MergeFrom(input).Build();
    }

    /// <summary>
    /// Parses an UnknownFieldSet from the given data.
    /// </summary>
    public static UnknownFieldSet ParseFrom(ByteString data) {
      return CreateBuilder().MergeFrom(data).Build();
    }

    /// <summary>
    /// Parses an UnknownFieldSet from the given data.
    /// </summary>
    public static UnknownFieldSet ParseFrom(byte[] data) {
      return CreateBuilder().MergeFrom(data).Build();
    }

    /// <summary>
    /// Parses an UnknownFieldSet from the given input.
    /// </summary>
    public static UnknownFieldSet ParseFrom(Stream input) {
      return CreateBuilder().MergeFrom(input).Build();
    }

240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266
    #region IMessageLite Members

    public bool IsInitialized {
      get { return fields != null; }
    }

    public void WriteDelimitedTo(Stream output) {
      CodedOutputStream codedOutput = CodedOutputStream.CreateInstance(output);
      codedOutput.WriteRawVarint32((uint) SerializedSize);
      WriteTo(codedOutput);
      codedOutput.Flush();
    }

    public IBuilderLite WeakCreateBuilderForType() {
      return new Builder();
    }

    public IBuilderLite WeakToBuilder() {
      return new Builder(fields);
    }

    public IMessageLite WeakDefaultInstanceForType {
      get { return defaultInstance; }
    }

    #endregion

Jon Skeet's avatar
Jon Skeet committed
267 268 269
    /// <summary>
    /// Builder for UnknownFieldSets.
    /// </summary>
270
    public sealed class Builder : IBuilderLite
Jon Skeet's avatar
Jon Skeet committed
271 272
    {
      /// <summary>
273
      /// Mapping from number to field. Note that by using a SortedList we ensure
Jon Skeet's avatar
Jon Skeet committed
274 275
      /// that the fields will be serialized in ascending order.
      /// </summary>
276
      private IDictionary<int, UnknownField> fields;
Jon Skeet's avatar
Jon Skeet committed
277 278 279
      // Optimization:  We keep around a builder for the last field that was
      // modified so that we can efficiently add to it multiple times in a
      // row (important when parsing an unknown repeated field).
280 281
      private int lastFieldNumber;
      private UnknownField.Builder lastField;
Jon Skeet's avatar
Jon Skeet committed
282 283

      internal Builder() {
284 285 286 287 288
        fields = new SortedList<int, UnknownField>();
      }

      internal Builder(IDictionary<int, UnknownField> dictionary) {
        fields = new SortedList<int, UnknownField>(dictionary); 
Jon Skeet's avatar
Jon Skeet committed
289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375
      }

      /// <summary>
      /// Returns a field builder for the specified field number, including any values
      /// which already exist.
      /// </summary>
      private UnknownField.Builder GetFieldBuilder(int number) {
        if (lastField != null) {
          if (number == lastFieldNumber) {
            return lastField;
          }
          // Note: AddField() will reset lastField and lastFieldNumber.
          AddField(lastFieldNumber, lastField.Build());
        }
        if (number == 0) {
          return null;
        }

        lastField = UnknownField.CreateBuilder();
        UnknownField existing;
        if (fields.TryGetValue(number, out existing)) {
          lastField.MergeFrom(existing);
        }
        lastFieldNumber = number;
        return lastField;
      }

      /// <summary>
      /// Build the UnknownFieldSet and return it. Once this method has been called,
      /// this instance will no longer be usable. Calling any method after this
      /// will throw a NullReferenceException.
      /// </summary>
      public UnknownFieldSet Build() {
        GetFieldBuilder(0);  // Force lastField to be built.
        UnknownFieldSet result = fields.Count == 0 ? DefaultInstance : new UnknownFieldSet(fields);
        fields = null;
        return result;
      }

      /// <summary>
      /// Adds a field to the set. If a field with the same number already exists, it
      /// is replaced.
      /// </summary>
      public Builder AddField(int number, UnknownField field) {
        if (number == 0) {
          throw new ArgumentOutOfRangeException("number", "Zero is not a valid field number.");
        }
        if (lastField != null && lastFieldNumber == number) {
          // Discard this.
          lastField = null;
          lastFieldNumber = 0;
        }
        fields[number] = field;
        return this;
      }

      /// <summary>
      /// Resets the builder to an empty set.
      /// </summary>
      public Builder Clear() {
        fields.Clear();
        lastFieldNumber = 0;
        lastField = null;
        return this;
      }
      
      /// <summary>
      /// Parse an entire message from <paramref name="input"/> and merge
      /// its fields into this set.
      /// </summary>
      public Builder MergeFrom(CodedInputStream input) {
        while (true) {
          uint tag = input.ReadTag();
          if (tag == 0 || !MergeFieldFrom(tag, input)) {
            break;
          }
        }
        return this;
      }

        /// <summary>
        /// Parse a single field from <paramref name="input"/> and merge it
        /// into this set.
        /// </summary>
        /// <param name="tag">The field's tag number, which was already parsed.</param>
        /// <param name="input">The coded input stream containing the field</param>
        /// <returns>false if the tag is an "end group" tag, true otherwise</returns>
Jon Skeet's avatar
Jon Skeet committed
376
      [CLSCompliant(false)]
Jon Skeet's avatar
Jon Skeet committed
377 378 379 380 381 382 383 384 385 386 387 388 389 390
      public bool MergeFieldFrom(uint tag, CodedInputStream input) {
        int number = WireFormat.GetTagFieldNumber(tag);
        switch (WireFormat.GetTagWireType(tag)) {
          case WireFormat.WireType.Varint:
            GetFieldBuilder(number).AddVarint(input.ReadUInt64());
            return true;
          case WireFormat.WireType.Fixed64:
            GetFieldBuilder(number).AddFixed64(input.ReadFixed64());
            return true;
          case WireFormat.WireType.LengthDelimited:
            GetFieldBuilder(number).AddLengthDelimited(input.ReadBytes());
            return true;
          case WireFormat.WireType.StartGroup: {
            Builder subBuilder = CreateBuilder();
391
#pragma warning disable 0612
Jon Skeet's avatar
Jon Skeet committed
392
            input.ReadUnknownGroup(number, subBuilder);
393
#pragma warning restore 0612
Jon Skeet's avatar
Jon Skeet committed
394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447
            GetFieldBuilder(number).AddGroup(subBuilder.Build());
            return true;
          }
          case WireFormat.WireType.EndGroup:
            return false;
          case WireFormat.WireType.Fixed32:
            GetFieldBuilder(number).AddFixed32(input.ReadFixed32());
            return true;
          default:
            throw InvalidProtocolBufferException.InvalidWireType();
        }
      }

      /// <summary>
      /// Parses <paramref name="input"/> as an UnknownFieldSet and merge it
      /// with the set being built. This is just a small wrapper around
      /// MergeFrom(CodedInputStream).
      /// </summary>
      public Builder MergeFrom(Stream input) {
        CodedInputStream codedInput = CodedInputStream.CreateInstance(input);
        MergeFrom(codedInput);
        codedInput.CheckLastTagWas(0);
        return this;
      }

      /// <summary>
      /// Parses <paramref name="data"/> as an UnknownFieldSet and merge it
      /// with the set being built. This is just a small wrapper around
      /// MergeFrom(CodedInputStream).
      /// </summary>
      public Builder MergeFrom(ByteString data) {
        CodedInputStream input = data.CreateCodedInput();
        MergeFrom(input);
        input.CheckLastTagWas(0);
        return this;
      }

      /// <summary>
      /// Parses <paramref name="data"/> as an UnknownFieldSet and merge it
      /// with the set being built. This is just a small wrapper around
      /// MergeFrom(CodedInputStream).
      /// </summary>
      public Builder MergeFrom(byte[] data) {
        CodedInputStream input = CodedInputStream.CreateInstance(data);
        MergeFrom(input);
        input.CheckLastTagWas(0);
        return this;
      }

      /// <summary>
      /// Convenience method for merging a new field containing a single varint
      /// value.  This is used in particular when an unknown enum value is
      /// encountered.
      /// </summary>
Jon Skeet's avatar
Jon Skeet committed
448
      [CLSCompliant(false)]
Jon Skeet's avatar
Jon Skeet committed
449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499
      public Builder MergeVarintField(int number, ulong value) {
        if (number == 0) {
          throw new ArgumentOutOfRangeException("number", "Zero is not a valid field number.");
        }
        GetFieldBuilder(number).AddVarint(value);
        return this;
      }

      /// <summary>
      /// Merges the fields from <paramref name="other"/> into this set.
      /// If a field number exists in both sets, the values in <paramref name="other"/>
      /// will be appended to the values in this set.
      /// </summary>
      public Builder MergeFrom(UnknownFieldSet other) {
        if (other != DefaultInstance) {
          foreach(KeyValuePair<int, UnknownField> entry in other.fields) {
            MergeField(entry.Key, entry.Value);
          }
        }
        return this;
      }

      /// <summary>
      /// Checks if the given field number is present in the set.
      /// </summary>
      public bool HasField(int number) {
        if (number == 0) {
          throw new ArgumentOutOfRangeException("number", "Zero is not a valid field number.");
        }
        return number == lastFieldNumber || fields.ContainsKey(number);
      }

      /// <summary>
      /// Adds a field to the unknown field set. If a field with the same
      /// number already exists, the two are merged.
      /// </summary>
      public Builder MergeField(int number, UnknownField field) {
        if (number == 0) {
          throw new ArgumentOutOfRangeException("number", "Zero is not a valid field number.");
        }
        if (HasField(number)) {
          GetFieldBuilder(number).MergeFrom(field);
        } else {
          // Optimization:  We could call getFieldBuilder(number).mergeFrom(field)
          // in this case, but that would create a copy of the Field object.
          // We'd rather reuse the one passed to us, so call AddField() instead.
          AddField(number, field);
        }
        return this;
      }

500
      internal void MergeFrom(CodedInputStream input, ExtensionRegistryLite extensionRegistryLite, IBuilder builder) {
Jon Skeet's avatar
Jon Skeet committed
501 502 503 504 505
        while (true) {
          uint tag = input.ReadTag();
          if (tag == 0) {
            break;
          }
506 507

          ExtensionRegistry extensionRegistry = (extensionRegistryLite as ExtensionRegistry) ?? ExtensionRegistry.CreateInstance();
Jon Skeet's avatar
Jon Skeet committed
508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523
          if (!MergeFieldFrom(input, extensionRegistry, builder, tag)) {
            // end group tag
            break;
          }
        }
      }

      /// <summary>
      /// Like <see cref="MergeFrom(CodedInputStream, ExtensionRegistry, IBuilder)" />
      /// but parses a single field.
      /// </summary>
      /// <param name="input">The input to read the field from</param>
      /// <param name="extensionRegistry">Registry to use when an extension field is encountered</param>
      /// <param name="builder">Builder to merge field into, if it's a known field</param>
      /// <param name="tag">The tag, which should already have been read from the input</param>
      /// <returns>true unless the tag is an end-group tag</returns>
524
      internal bool MergeFieldFrom(CodedInputStream input,
Jon Skeet's avatar
Jon Skeet committed
525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551
          ExtensionRegistry extensionRegistry, IBuilder builder, uint tag) {

        MessageDescriptor type = builder.DescriptorForType;
        if (type.Options.MessageSetWireFormat && tag == WireFormat.MessageSetTag.ItemStart) {
          MergeMessageSetExtensionFromCodedStream(input, extensionRegistry, builder);
          return true;
        }

        WireFormat.WireType wireType = WireFormat.GetTagWireType(tag);
        int fieldNumber = WireFormat.GetTagFieldNumber(tag);

        FieldDescriptor field;
        IMessage defaultFieldInstance = null;

        if (type.IsExtensionNumber(fieldNumber)) {
          ExtensionInfo extension = extensionRegistry[type, fieldNumber];
          if (extension == null) {
            field = null;
          } else {
            field = extension.Descriptor;
            defaultFieldInstance = extension.DefaultInstance;
          }
        } else {
          field = type.FindFieldByNumber(fieldNumber);
        }

        // Unknown field or wrong wire type. Skip.
552
        if (field == null || wireType != WireFormat.GetWireType(field)) {
Jon Skeet's avatar
Jon Skeet committed
553 554 555
          return MergeFieldFrom(tag, input);
        }

556 557 558 559 560
        if (field.IsPacked) {
          int length = (int)input.ReadRawVarint32();
          int limit = input.PushLimit(length);
          if (field.FieldType == FieldType.Enum) {
            while (!input.ReachedLimit) {
Jon Skeet's avatar
Jon Skeet committed
561
              int rawValue = input.ReadEnum();
562
              object value = field.EnumType.FindValueByNumber(rawValue);
Jon Skeet's avatar
Jon Skeet committed
563
              if (value == null) {
564 565
                // If the number isn't recognized as a valid value for this
                // enum, drop it (don't even add it to unknownFields).
Jon Skeet's avatar
Jon Skeet committed
566 567
                return true;
              }
568
              builder.WeakAddRepeatedField(field, value);
Jon Skeet's avatar
Jon Skeet committed
569
            }
570 571 572 573 574 575 576
          } else {
            while (!input.ReachedLimit) {
              Object value = input.ReadPrimitiveField(field.FieldType);
              builder.WeakAddRepeatedField(field, value);
            }
          }
          input.PopLimit(limit);
Jon Skeet's avatar
Jon Skeet committed
577
        } else {
578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618
          object value;
          switch (field.FieldType) {
            case FieldType.Group:
            case FieldType.Message: {
                IBuilder subBuilder;
                if (defaultFieldInstance != null) {
                  subBuilder = defaultFieldInstance.WeakCreateBuilderForType();
                } else {
                  subBuilder = builder.CreateBuilderForField(field);
                }
                if (!field.IsRepeated) {
                  subBuilder.WeakMergeFrom((IMessage)builder[field]);
                }
                if (field.FieldType == FieldType.Group) {
                  input.ReadGroup(field.FieldNumber, subBuilder, extensionRegistry);
                } else {
                  input.ReadMessage(subBuilder, extensionRegistry);
                }
                value = subBuilder.WeakBuild();
                break;
              }
            case FieldType.Enum: {
                int rawValue = input.ReadEnum();
                value = field.EnumType.FindValueByNumber(rawValue);
                // If the number isn't recognized as a valid value for this enum,
                // drop it.
                if (value == null) {
                  MergeVarintField(fieldNumber, (ulong)rawValue);
                  return true;
                }
                break;
              }
            default:
              value = input.ReadPrimitiveField(field.FieldType);
              break;
          }
          if (field.IsRepeated) {
            builder.WeakAddRepeatedField(field, value);
          } else {
            builder[field] = value;
          }
Jon Skeet's avatar
Jon Skeet committed
619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710
        }
        return true;
      }

      /// <summary>
      /// Called by MergeFieldFrom to parse a MessageSet extension.
      /// </summary>
      private void MergeMessageSetExtensionFromCodedStream(CodedInputStream input,
          ExtensionRegistry extensionRegistry, IBuilder builder) {
        MessageDescriptor type = builder.DescriptorForType;

        // The wire format for MessageSet is:
        //   message MessageSet {
        //     repeated group Item = 1 {
        //       required int32 typeId = 2;
        //       required bytes message = 3;
        //     }
        //   }
        // "typeId" is the extension's field number.  The extension can only be
        // a message type, where "message" contains the encoded bytes of that
        // message.
        //
        // In practice, we will probably never see a MessageSet item in which
        // the message appears before the type ID, or where either field does not
        // appear exactly once.  However, in theory such cases are valid, so we
        // should be prepared to accept them.

        int typeId = 0;
        ByteString rawBytes = null;  // If we encounter "message" before "typeId"
        IBuilder subBuilder = null;
        FieldDescriptor field = null;

        while (true) {
          uint tag = input.ReadTag();
          if (tag == 0) {
            break;
          }

          if (tag == WireFormat.MessageSetTag.TypeID) {
            typeId = input.ReadInt32();
            // Zero is not a valid type ID.
            if (typeId != 0) {
              ExtensionInfo extension = extensionRegistry[type, typeId];
              if (extension != null) {
                field = extension.Descriptor;
                subBuilder = extension.DefaultInstance.WeakCreateBuilderForType();
                IMessage originalMessage = (IMessage)builder[field];
                if (originalMessage != null) {
                  subBuilder.WeakMergeFrom(originalMessage);
                }
                if (rawBytes != null) {
                  // We already encountered the message.  Parse it now.
                  // TODO(jonskeet): Check this is okay. It's subtly different from the Java, as it doesn't create an input stream from rawBytes.
                  // In fact, why don't we just call MergeFrom(rawBytes)? And what about the extension registry?
                  subBuilder.WeakMergeFrom(rawBytes.CreateCodedInput());
                  rawBytes = null;
                }
              } else {
                // Unknown extension number.  If we already saw data, put it
                // in rawBytes.
                if (rawBytes != null) {
                  MergeField(typeId, UnknownField.CreateBuilder().AddLengthDelimited(rawBytes).Build());
                  rawBytes = null;
                }
              }
            }
          } else if (tag == WireFormat.MessageSetTag.Message) {
            if (typeId == 0) {
              // We haven't seen a type ID yet, so we have to store the raw bytes for now.
              rawBytes = input.ReadBytes();
            } else if (subBuilder == null) {
              // We don't know how to parse this.  Ignore it.
              MergeField(typeId, UnknownField.CreateBuilder().AddLengthDelimited(input.ReadBytes()).Build());
            } else {
              // We already know the type, so we can parse directly from the input
              // with no copying.  Hooray!
              input.ReadMessage(subBuilder, extensionRegistry);
            }
          } else {
            // Unknown tag.  Skip it.
            if (!input.SkipField(tag)) {
              break;  // end of group
            }
          }
        }

        input.CheckLastTagWas(WireFormat.MessageSetTag.ItemEnd);

        if (subBuilder != null) {
          builder[field] = subBuilder.WeakBuild();
        }
      }
711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758

      #region IBuilderLite Members

      bool IBuilderLite.IsInitialized {
        get { return fields != null; }
      }

      IBuilderLite IBuilderLite.WeakClear() {
        return Clear();
      }

      IBuilderLite IBuilderLite.WeakMergeFrom(IMessageLite message) {
        return MergeFrom((UnknownFieldSet)message);
      }

      IBuilderLite IBuilderLite.WeakMergeFrom(ByteString data) {
        return MergeFrom(data);
      }

      IBuilderLite IBuilderLite.WeakMergeFrom(ByteString data, ExtensionRegistryLite registry) {
        return MergeFrom(data);
      }

      IBuilderLite IBuilderLite.WeakMergeFrom(CodedInputStream input) {
        return MergeFrom(input);
      }

      IBuilderLite IBuilderLite.WeakMergeFrom(CodedInputStream input, ExtensionRegistryLite registry) {
        return MergeFrom(input);
      }

      IMessageLite IBuilderLite.WeakBuild() {
        return Build();
      }

      IMessageLite IBuilderLite.WeakBuildPartial() {
        return Build();
      }

      IBuilderLite IBuilderLite.WeakClone() {
        return Build().WeakToBuilder();
      }

      IMessageLite IBuilderLite.WeakDefaultInstanceForType {
        get { return DefaultInstance; }
      }

      #endregion
Jon Skeet's avatar
Jon Skeet committed
759 760 761
    }
  }
}