834 lines
30 KiB
C#
834 lines
30 KiB
C#
#region License
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// Copyright (c) 2007 James Newton-King
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//
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// Permission is hereby granted, free of charge, to any person
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// obtaining a copy of this software and associated documentation
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// files (the "Software"), to deal in the Software without
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// restriction, including without limitation the rights to use,
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// copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the
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// Software is furnished to do so, subject to the following
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// conditions:
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//
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// The above copyright notice and this permission notice shall be
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// included in all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
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// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
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// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
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// OTHER DEALINGS IN THE SOFTWARE.
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#endregion
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using System;
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using System.Collections.Generic;
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using System.Globalization;
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using System.Text;
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using System.IO;
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using LC.Newtonsoft.Json.Serialization;
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using LC.Newtonsoft.Json.Utilities;
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using LC.Newtonsoft.Json.Linq;
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namespace LC.Newtonsoft.Json.Bson
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{
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/// <summary>
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/// Represents a reader that provides fast, non-cached, forward-only access to serialized BSON data.
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/// </summary>
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[Obsolete("BSON reading and writing has been moved to its own package. See https://www.nuget.org/packages/Newtonsoft.Json.Bson for more details.")]
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public class BsonReader : JsonReader
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{
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private const int MaxCharBytesSize = 128;
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private static readonly byte[] SeqRange1 = new byte[] { 0, 127 }; // range of 1-byte sequence
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private static readonly byte[] SeqRange2 = new byte[] { 194, 223 }; // range of 2-byte sequence
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private static readonly byte[] SeqRange3 = new byte[] { 224, 239 }; // range of 3-byte sequence
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private static readonly byte[] SeqRange4 = new byte[] { 240, 244 }; // range of 4-byte sequence
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private readonly BinaryReader _reader;
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private readonly List<ContainerContext> _stack;
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private byte[] _byteBuffer;
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private char[] _charBuffer;
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private BsonType _currentElementType;
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private BsonReaderState _bsonReaderState;
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private ContainerContext _currentContext;
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private bool _readRootValueAsArray;
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private bool _jsonNet35BinaryCompatibility;
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private DateTimeKind _dateTimeKindHandling;
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private enum BsonReaderState
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{
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Normal = 0,
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ReferenceStart = 1,
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ReferenceRef = 2,
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ReferenceId = 3,
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CodeWScopeStart = 4,
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CodeWScopeCode = 5,
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CodeWScopeScope = 6,
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CodeWScopeScopeObject = 7,
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CodeWScopeScopeEnd = 8
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}
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private class ContainerContext
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{
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public readonly BsonType Type;
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public int Length;
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public int Position;
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public ContainerContext(BsonType type)
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{
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Type = type;
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}
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}
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/// <summary>
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/// Gets or sets a value indicating whether binary data reading should be compatible with incorrect Json.NET 3.5 written binary.
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/// </summary>
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/// <value>
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/// <c>true</c> if binary data reading will be compatible with incorrect Json.NET 3.5 written binary; otherwise, <c>false</c>.
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/// </value>
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[Obsolete("JsonNet35BinaryCompatibility will be removed in a future version of Json.NET.")]
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public bool JsonNet35BinaryCompatibility
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{
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get => _jsonNet35BinaryCompatibility;
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set => _jsonNet35BinaryCompatibility = value;
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}
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/// <summary>
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/// Gets or sets a value indicating whether the root object will be read as a JSON array.
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/// </summary>
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/// <value>
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/// <c>true</c> if the root object will be read as a JSON array; otherwise, <c>false</c>.
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/// </value>
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public bool ReadRootValueAsArray
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{
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get => _readRootValueAsArray;
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set => _readRootValueAsArray = value;
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}
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/// <summary>
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/// Gets or sets the <see cref="DateTimeKind" /> used when reading <see cref="DateTime"/> values from BSON.
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/// </summary>
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/// <value>The <see cref="DateTimeKind" /> used when reading <see cref="DateTime"/> values from BSON.</value>
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public DateTimeKind DateTimeKindHandling
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{
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get => _dateTimeKindHandling;
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set => _dateTimeKindHandling = value;
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}
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/// <summary>
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/// Initializes a new instance of the <see cref="BsonReader"/> class.
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/// </summary>
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/// <param name="stream">The <see cref="Stream"/> containing the BSON data to read.</param>
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public BsonReader(Stream stream)
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: this(stream, false, DateTimeKind.Local)
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{
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}
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/// <summary>
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/// Initializes a new instance of the <see cref="BsonReader"/> class.
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/// </summary>
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/// <param name="reader">The <see cref="BinaryReader"/> containing the BSON data to read.</param>
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public BsonReader(BinaryReader reader)
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: this(reader, false, DateTimeKind.Local)
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{
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}
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/// <summary>
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/// Initializes a new instance of the <see cref="BsonReader"/> class.
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/// </summary>
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/// <param name="stream">The <see cref="Stream"/> containing the BSON data to read.</param>
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/// <param name="readRootValueAsArray">if set to <c>true</c> the root object will be read as a JSON array.</param>
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/// <param name="dateTimeKindHandling">The <see cref="DateTimeKind" /> used when reading <see cref="DateTime"/> values from BSON.</param>
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public BsonReader(Stream stream, bool readRootValueAsArray, DateTimeKind dateTimeKindHandling)
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{
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ValidationUtils.ArgumentNotNull(stream, nameof(stream));
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_reader = new BinaryReader(stream);
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_stack = new List<ContainerContext>();
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_readRootValueAsArray = readRootValueAsArray;
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_dateTimeKindHandling = dateTimeKindHandling;
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}
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/// <summary>
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/// Initializes a new instance of the <see cref="BsonReader"/> class.
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/// </summary>
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/// <param name="reader">The <see cref="BinaryReader"/> containing the BSON data to read.</param>
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/// <param name="readRootValueAsArray">if set to <c>true</c> the root object will be read as a JSON array.</param>
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/// <param name="dateTimeKindHandling">The <see cref="DateTimeKind" /> used when reading <see cref="DateTime"/> values from BSON.</param>
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public BsonReader(BinaryReader reader, bool readRootValueAsArray, DateTimeKind dateTimeKindHandling)
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{
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ValidationUtils.ArgumentNotNull(reader, nameof(reader));
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_reader = reader;
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_stack = new List<ContainerContext>();
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_readRootValueAsArray = readRootValueAsArray;
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_dateTimeKindHandling = dateTimeKindHandling;
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}
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private string ReadElement()
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{
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_currentElementType = ReadType();
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string elementName = ReadString();
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return elementName;
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}
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/// <summary>
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/// Reads the next JSON token from the underlying <see cref="Stream"/>.
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/// </summary>
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/// <returns>
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/// <c>true</c> if the next token was read successfully; <c>false</c> if there are no more tokens to read.
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/// </returns>
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public override bool Read()
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{
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try
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{
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bool success;
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switch (_bsonReaderState)
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{
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case BsonReaderState.Normal:
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success = ReadNormal();
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break;
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case BsonReaderState.ReferenceStart:
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case BsonReaderState.ReferenceRef:
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case BsonReaderState.ReferenceId:
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success = ReadReference();
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break;
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case BsonReaderState.CodeWScopeStart:
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case BsonReaderState.CodeWScopeCode:
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case BsonReaderState.CodeWScopeScope:
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case BsonReaderState.CodeWScopeScopeObject:
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case BsonReaderState.CodeWScopeScopeEnd:
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success = ReadCodeWScope();
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break;
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default:
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throw JsonReaderException.Create(this, "Unexpected state: {0}".FormatWith(CultureInfo.InvariantCulture, _bsonReaderState));
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}
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if (!success)
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{
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SetToken(JsonToken.None);
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return false;
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}
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return true;
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}
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catch (EndOfStreamException)
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{
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SetToken(JsonToken.None);
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return false;
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}
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}
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/// <summary>
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/// Changes the reader's state to <see cref="JsonReader.State.Closed"/>.
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/// If <see cref="JsonReader.CloseInput"/> is set to <c>true</c>, the underlying <see cref="Stream"/> is also closed.
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/// </summary>
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public override void Close()
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{
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base.Close();
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if (CloseInput)
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{
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#if HAVE_STREAM_READER_WRITER_CLOSE
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_reader?.Close();
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#else
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_reader?.Dispose();
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#endif
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}
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}
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private bool ReadCodeWScope()
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{
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switch (_bsonReaderState)
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{
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case BsonReaderState.CodeWScopeStart:
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SetToken(JsonToken.PropertyName, "$code");
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_bsonReaderState = BsonReaderState.CodeWScopeCode;
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return true;
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case BsonReaderState.CodeWScopeCode:
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// total CodeWScope size - not used
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ReadInt32();
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SetToken(JsonToken.String, ReadLengthString());
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_bsonReaderState = BsonReaderState.CodeWScopeScope;
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return true;
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case BsonReaderState.CodeWScopeScope:
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if (CurrentState == State.PostValue)
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{
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SetToken(JsonToken.PropertyName, "$scope");
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return true;
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}
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else
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{
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SetToken(JsonToken.StartObject);
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_bsonReaderState = BsonReaderState.CodeWScopeScopeObject;
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ContainerContext newContext = new ContainerContext(BsonType.Object);
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PushContext(newContext);
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newContext.Length = ReadInt32();
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return true;
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}
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case BsonReaderState.CodeWScopeScopeObject:
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bool result = ReadNormal();
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if (result && TokenType == JsonToken.EndObject)
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{
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_bsonReaderState = BsonReaderState.CodeWScopeScopeEnd;
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}
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return result;
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case BsonReaderState.CodeWScopeScopeEnd:
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SetToken(JsonToken.EndObject);
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_bsonReaderState = BsonReaderState.Normal;
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return true;
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default:
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throw new ArgumentOutOfRangeException();
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}
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}
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private bool ReadReference()
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{
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switch (CurrentState)
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{
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case State.ObjectStart:
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{
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SetToken(JsonToken.PropertyName, JsonTypeReflector.RefPropertyName);
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_bsonReaderState = BsonReaderState.ReferenceRef;
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return true;
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}
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case State.Property:
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{
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if (_bsonReaderState == BsonReaderState.ReferenceRef)
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{
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SetToken(JsonToken.String, ReadLengthString());
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return true;
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}
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else if (_bsonReaderState == BsonReaderState.ReferenceId)
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{
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SetToken(JsonToken.Bytes, ReadBytes(12));
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return true;
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}
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else
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{
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throw JsonReaderException.Create(this, "Unexpected state when reading BSON reference: " + _bsonReaderState);
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}
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}
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case State.PostValue:
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{
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if (_bsonReaderState == BsonReaderState.ReferenceRef)
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{
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SetToken(JsonToken.PropertyName, JsonTypeReflector.IdPropertyName);
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_bsonReaderState = BsonReaderState.ReferenceId;
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return true;
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}
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else if (_bsonReaderState == BsonReaderState.ReferenceId)
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{
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SetToken(JsonToken.EndObject);
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_bsonReaderState = BsonReaderState.Normal;
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return true;
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}
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else
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{
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throw JsonReaderException.Create(this, "Unexpected state when reading BSON reference: " + _bsonReaderState);
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}
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}
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default:
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throw JsonReaderException.Create(this, "Unexpected state when reading BSON reference: " + CurrentState);
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}
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}
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private bool ReadNormal()
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{
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switch (CurrentState)
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{
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case State.Start:
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{
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JsonToken token = (!_readRootValueAsArray) ? JsonToken.StartObject : JsonToken.StartArray;
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BsonType type = (!_readRootValueAsArray) ? BsonType.Object : BsonType.Array;
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SetToken(token);
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ContainerContext newContext = new ContainerContext(type);
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PushContext(newContext);
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newContext.Length = ReadInt32();
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return true;
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}
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case State.Complete:
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case State.Closed:
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return false;
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case State.Property:
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{
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ReadType(_currentElementType);
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return true;
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}
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case State.ObjectStart:
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case State.ArrayStart:
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case State.PostValue:
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ContainerContext context = _currentContext;
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if (context == null)
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{
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if (SupportMultipleContent)
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{
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goto case State.Start;
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}
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return false;
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}
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int lengthMinusEnd = context.Length - 1;
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if (context.Position < lengthMinusEnd)
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{
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if (context.Type == BsonType.Array)
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{
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ReadElement();
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ReadType(_currentElementType);
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return true;
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}
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else
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{
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SetToken(JsonToken.PropertyName, ReadElement());
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return true;
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}
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}
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else if (context.Position == lengthMinusEnd)
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{
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if (ReadByte() != 0)
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{
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throw JsonReaderException.Create(this, "Unexpected end of object byte value.");
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}
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PopContext();
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if (_currentContext != null)
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{
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MovePosition(context.Length);
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}
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JsonToken endToken = (context.Type == BsonType.Object) ? JsonToken.EndObject : JsonToken.EndArray;
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SetToken(endToken);
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return true;
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}
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else
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{
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throw JsonReaderException.Create(this, "Read past end of current container context.");
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}
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case State.ConstructorStart:
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break;
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case State.Constructor:
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break;
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case State.Error:
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break;
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case State.Finished:
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break;
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default:
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throw new ArgumentOutOfRangeException();
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}
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return false;
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}
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private void PopContext()
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{
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_stack.RemoveAt(_stack.Count - 1);
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if (_stack.Count == 0)
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{
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_currentContext = null;
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}
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else
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{
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_currentContext = _stack[_stack.Count - 1];
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}
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}
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private void PushContext(ContainerContext newContext)
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{
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_stack.Add(newContext);
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_currentContext = newContext;
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}
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private byte ReadByte()
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{
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MovePosition(1);
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return _reader.ReadByte();
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}
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private void ReadType(BsonType type)
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{
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switch (type)
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{
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case BsonType.Number:
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double d = ReadDouble();
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if (_floatParseHandling == FloatParseHandling.Decimal)
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{
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SetToken(JsonToken.Float, Convert.ToDecimal(d, CultureInfo.InvariantCulture));
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}
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else
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{
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SetToken(JsonToken.Float, d);
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}
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break;
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case BsonType.String:
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case BsonType.Symbol:
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SetToken(JsonToken.String, ReadLengthString());
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break;
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case BsonType.Object:
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{
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SetToken(JsonToken.StartObject);
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ContainerContext newContext = new ContainerContext(BsonType.Object);
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PushContext(newContext);
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newContext.Length = ReadInt32();
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break;
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}
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case BsonType.Array:
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{
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SetToken(JsonToken.StartArray);
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ContainerContext newContext = new ContainerContext(BsonType.Array);
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PushContext(newContext);
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newContext.Length = ReadInt32();
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break;
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}
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case BsonType.Binary:
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BsonBinaryType binaryType;
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byte[] data = ReadBinary(out binaryType);
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object value = (binaryType != BsonBinaryType.Uuid)
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? data
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: (object)new Guid(data);
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SetToken(JsonToken.Bytes, value);
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break;
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case BsonType.Undefined:
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SetToken(JsonToken.Undefined);
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break;
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case BsonType.Oid:
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byte[] oid = ReadBytes(12);
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SetToken(JsonToken.Bytes, oid);
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break;
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case BsonType.Boolean:
|
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bool b = Convert.ToBoolean(ReadByte());
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SetToken(JsonToken.Boolean, b);
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break;
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|
case BsonType.Date:
|
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long ticks = ReadInt64();
|
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DateTime utcDateTime = DateTimeUtils.ConvertJavaScriptTicksToDateTime(ticks);
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|
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DateTime dateTime;
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switch (DateTimeKindHandling)
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{
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case DateTimeKind.Unspecified:
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dateTime = DateTime.SpecifyKind(utcDateTime, DateTimeKind.Unspecified);
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break;
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case DateTimeKind.Local:
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dateTime = utcDateTime.ToLocalTime();
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break;
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default:
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dateTime = utcDateTime;
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break;
|
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}
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SetToken(JsonToken.Date, dateTime);
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break;
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case BsonType.Null:
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SetToken(JsonToken.Null);
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break;
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case BsonType.Regex:
|
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string expression = ReadString();
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string modifiers = ReadString();
|
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|
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string regex = @"/" + expression + @"/" + modifiers;
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SetToken(JsonToken.String, regex);
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break;
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case BsonType.Reference:
|
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SetToken(JsonToken.StartObject);
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_bsonReaderState = BsonReaderState.ReferenceStart;
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break;
|
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case BsonType.Code:
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SetToken(JsonToken.String, ReadLengthString());
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break;
|
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case BsonType.CodeWScope:
|
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SetToken(JsonToken.StartObject);
|
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_bsonReaderState = BsonReaderState.CodeWScopeStart;
|
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break;
|
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case BsonType.Integer:
|
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SetToken(JsonToken.Integer, (long)ReadInt32());
|
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break;
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case BsonType.TimeStamp:
|
|
case BsonType.Long:
|
|
SetToken(JsonToken.Integer, ReadInt64());
|
|
break;
|
|
default:
|
|
throw new ArgumentOutOfRangeException(nameof(type), "Unexpected BsonType value: " + type);
|
|
}
|
|
}
|
|
|
|
private byte[] ReadBinary(out BsonBinaryType binaryType)
|
|
{
|
|
int dataLength = ReadInt32();
|
|
|
|
binaryType = (BsonBinaryType)ReadByte();
|
|
|
|
#pragma warning disable 612,618
|
|
// the old binary type has the data length repeated in the data for some reason
|
|
if (binaryType == BsonBinaryType.BinaryOld && !_jsonNet35BinaryCompatibility)
|
|
{
|
|
dataLength = ReadInt32();
|
|
}
|
|
#pragma warning restore 612,618
|
|
|
|
return ReadBytes(dataLength);
|
|
}
|
|
|
|
private string ReadString()
|
|
{
|
|
EnsureBuffers();
|
|
|
|
StringBuilder builder = null;
|
|
|
|
int totalBytesRead = 0;
|
|
// used in case of left over multibyte characters in the buffer
|
|
int offset = 0;
|
|
while (true)
|
|
{
|
|
int count = offset;
|
|
byte b;
|
|
while (count < MaxCharBytesSize && (b = _reader.ReadByte()) > 0)
|
|
{
|
|
_byteBuffer[count++] = b;
|
|
}
|
|
int byteCount = count - offset;
|
|
totalBytesRead += byteCount;
|
|
|
|
if (count < MaxCharBytesSize && builder == null)
|
|
{
|
|
// pref optimization to avoid reading into a string builder
|
|
// if string is smaller than the buffer then return it directly
|
|
int length = Encoding.UTF8.GetChars(_byteBuffer, 0, byteCount, _charBuffer, 0);
|
|
|
|
MovePosition(totalBytesRead + 1);
|
|
return new string(_charBuffer, 0, length);
|
|
}
|
|
else
|
|
{
|
|
// calculate the index of the end of the last full character in the buffer
|
|
int lastFullCharStop = GetLastFullCharStop(count - 1);
|
|
|
|
int charCount = Encoding.UTF8.GetChars(_byteBuffer, 0, lastFullCharStop + 1, _charBuffer, 0);
|
|
|
|
if (builder == null)
|
|
{
|
|
builder = new StringBuilder(MaxCharBytesSize * 2);
|
|
}
|
|
|
|
builder.Append(_charBuffer, 0, charCount);
|
|
|
|
if (lastFullCharStop < byteCount - 1)
|
|
{
|
|
offset = byteCount - lastFullCharStop - 1;
|
|
// copy left over multi byte characters to beginning of buffer for next iteration
|
|
Array.Copy(_byteBuffer, lastFullCharStop + 1, _byteBuffer, 0, offset);
|
|
}
|
|
else
|
|
{
|
|
// reached end of string
|
|
if (count < MaxCharBytesSize)
|
|
{
|
|
MovePosition(totalBytesRead + 1);
|
|
return builder.ToString();
|
|
}
|
|
|
|
offset = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
private string ReadLengthString()
|
|
{
|
|
int length = ReadInt32();
|
|
|
|
MovePosition(length);
|
|
|
|
string s = GetString(length - 1);
|
|
_reader.ReadByte();
|
|
|
|
return s;
|
|
}
|
|
|
|
private string GetString(int length)
|
|
{
|
|
if (length == 0)
|
|
{
|
|
return string.Empty;
|
|
}
|
|
|
|
EnsureBuffers();
|
|
|
|
StringBuilder builder = null;
|
|
|
|
int totalBytesRead = 0;
|
|
|
|
// used in case of left over multibyte characters in the buffer
|
|
int offset = 0;
|
|
do
|
|
{
|
|
int count = ((length - totalBytesRead) > MaxCharBytesSize - offset)
|
|
? MaxCharBytesSize - offset
|
|
: length - totalBytesRead;
|
|
|
|
int byteCount = _reader.Read(_byteBuffer, offset, count);
|
|
|
|
if (byteCount == 0)
|
|
{
|
|
throw new EndOfStreamException("Unable to read beyond the end of the stream.");
|
|
}
|
|
|
|
totalBytesRead += byteCount;
|
|
|
|
// Above, byteCount is how many bytes we read this time.
|
|
// Below, byteCount is how many bytes are in the _byteBuffer.
|
|
byteCount += offset;
|
|
|
|
if (byteCount == length)
|
|
{
|
|
// pref optimization to avoid reading into a string builder
|
|
// first iteration and all bytes read then return string directly
|
|
int charCount = Encoding.UTF8.GetChars(_byteBuffer, 0, byteCount, _charBuffer, 0);
|
|
return new string(_charBuffer, 0, charCount);
|
|
}
|
|
else
|
|
{
|
|
int lastFullCharStop = GetLastFullCharStop(byteCount - 1);
|
|
|
|
if (builder == null)
|
|
{
|
|
builder = new StringBuilder(length);
|
|
}
|
|
|
|
int charCount = Encoding.UTF8.GetChars(_byteBuffer, 0, lastFullCharStop + 1, _charBuffer, 0);
|
|
builder.Append(_charBuffer, 0, charCount);
|
|
|
|
if (lastFullCharStop < byteCount - 1)
|
|
{
|
|
offset = byteCount - lastFullCharStop - 1;
|
|
// copy left over multi byte characters to beginning of buffer for next iteration
|
|
Array.Copy(_byteBuffer, lastFullCharStop + 1, _byteBuffer, 0, offset);
|
|
}
|
|
else
|
|
{
|
|
offset = 0;
|
|
}
|
|
}
|
|
} while (totalBytesRead < length);
|
|
|
|
return builder.ToString();
|
|
}
|
|
|
|
private int GetLastFullCharStop(int start)
|
|
{
|
|
int lookbackPos = start;
|
|
int bis = 0;
|
|
while (lookbackPos >= 0)
|
|
{
|
|
bis = BytesInSequence(_byteBuffer[lookbackPos]);
|
|
if (bis == 0)
|
|
{
|
|
lookbackPos--;
|
|
continue;
|
|
}
|
|
else if (bis == 1)
|
|
{
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
lookbackPos--;
|
|
break;
|
|
}
|
|
}
|
|
if (bis == start - lookbackPos)
|
|
{
|
|
//Full character.
|
|
return start;
|
|
}
|
|
else
|
|
{
|
|
return lookbackPos;
|
|
}
|
|
}
|
|
|
|
private int BytesInSequence(byte b)
|
|
{
|
|
if (b <= SeqRange1[1])
|
|
{
|
|
return 1;
|
|
}
|
|
if (b >= SeqRange2[0] && b <= SeqRange2[1])
|
|
{
|
|
return 2;
|
|
}
|
|
if (b >= SeqRange3[0] && b <= SeqRange3[1])
|
|
{
|
|
return 3;
|
|
}
|
|
if (b >= SeqRange4[0] && b <= SeqRange4[1])
|
|
{
|
|
return 4;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
private void EnsureBuffers()
|
|
{
|
|
if (_byteBuffer == null)
|
|
{
|
|
_byteBuffer = new byte[MaxCharBytesSize];
|
|
}
|
|
if (_charBuffer == null)
|
|
{
|
|
int charBufferSize = Encoding.UTF8.GetMaxCharCount(MaxCharBytesSize);
|
|
_charBuffer = new char[charBufferSize];
|
|
}
|
|
}
|
|
|
|
private double ReadDouble()
|
|
{
|
|
MovePosition(8);
|
|
return _reader.ReadDouble();
|
|
}
|
|
|
|
private int ReadInt32()
|
|
{
|
|
MovePosition(4);
|
|
return _reader.ReadInt32();
|
|
}
|
|
|
|
private long ReadInt64()
|
|
{
|
|
MovePosition(8);
|
|
return _reader.ReadInt64();
|
|
}
|
|
|
|
private BsonType ReadType()
|
|
{
|
|
MovePosition(1);
|
|
return (BsonType)_reader.ReadSByte();
|
|
}
|
|
|
|
private void MovePosition(int count)
|
|
{
|
|
_currentContext.Position += count;
|
|
}
|
|
|
|
private byte[] ReadBytes(int count)
|
|
{
|
|
MovePosition(count);
|
|
return _reader.ReadBytes(count);
|
|
}
|
|
}
|
|
} |