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1285 lines
46 KiB
1285 lines
46 KiB
#region Copyright notice and license
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// Protocol Buffers - Google's data interchange format
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// Copyright 2008 Google Inc. All rights reserved.
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// https://developers.google.com/protocol-buffers/
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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// * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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// * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#endregion
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using Google.Protobuf.Collections;
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using System;
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using System.Collections.Generic;
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using System.IO;
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namespace Google.Protobuf
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{
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/// <summary>
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/// Reads and decodes protocol message fields.
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/// </summary>
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/// <remarks>
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/// <para>
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/// This class is generally used by generated code to read appropriate
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/// primitives from the stream. It effectively encapsulates the lowest
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/// levels of protocol buffer format.
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/// </para>
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/// <para>
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/// Repeated fields and map fields are not handled by this class; use <see cref="RepeatedField{T}"/>
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/// and <see cref="MapField{TKey, TValue}"/> to serialize such fields.
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/// </para>
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/// </remarks>
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public sealed class CodedInputStream : IDisposable
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{
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/// <summary>
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/// Whether to leave the underlying stream open when disposing of this stream.
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/// This is always true when there's no stream.
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/// </summary>
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private readonly bool leaveOpen;
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/// <summary>
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/// Buffer of data read from the stream or provided at construction time.
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/// </summary>
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private readonly byte[] buffer;
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/// <summary>
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/// The index of the buffer at which we need to refill from the stream (if there is one).
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/// </summary>
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private int bufferSize;
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private int bufferSizeAfterLimit = 0;
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/// <summary>
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/// The position within the current buffer (i.e. the next byte to read)
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/// </summary>
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private int bufferPos = 0;
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/// <summary>
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/// The stream to read further input from, or null if the byte array buffer was provided
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/// directly on construction, with no further data available.
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/// </summary>
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private readonly Stream input;
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/// <summary>
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/// The last tag we read. 0 indicates we've read to the end of the stream
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/// (or haven't read anything yet).
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/// </summary>
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private uint lastTag = 0;
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/// <summary>
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/// The next tag, used to store the value read by PeekTag.
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/// </summary>
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private uint nextTag = 0;
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private bool hasNextTag = false;
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internal const int DefaultRecursionLimit = 64;
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internal const int DefaultSizeLimit = 64 << 20; // 64MB
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internal const int BufferSize = 4096;
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/// <summary>
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/// The total number of bytes read before the current buffer. The
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/// total bytes read up to the current position can be computed as
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/// totalBytesRetired + bufferPos.
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/// </summary>
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private int totalBytesRetired = 0;
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/// <summary>
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/// The absolute position of the end of the current message.
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/// </summary>
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private int currentLimit = int.MaxValue;
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private int recursionDepth = 0;
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private readonly int recursionLimit;
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private readonly int sizeLimit;
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#region Construction
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// Note that the checks are performed such that we don't end up checking obviously-valid things
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// like non-null references for arrays we've just created.
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/// <summary>
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/// Creates a new CodedInputStream reading data from the given byte array.
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/// </summary>
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public CodedInputStream(byte[] buffer) : this(null, ProtoPreconditions.CheckNotNull(buffer, "buffer"), 0, buffer.Length)
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{
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}
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/// <summary>
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/// Creates a new <see cref="CodedInputStream"/> that reads from the given byte array slice.
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/// </summary>
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public CodedInputStream(byte[] buffer, int offset, int length)
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: this(null, ProtoPreconditions.CheckNotNull(buffer, "buffer"), offset, offset + length)
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{
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if (offset < 0 || offset > buffer.Length)
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{
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throw new ArgumentOutOfRangeException("offset", "Offset must be within the buffer");
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}
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if (length < 0 || offset + length > buffer.Length)
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{
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throw new ArgumentOutOfRangeException("length", "Length must be non-negative and within the buffer");
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}
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}
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/// <summary>
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/// Creates a new <see cref="CodedInputStream"/> reading data from the given stream, which will be disposed
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/// when the returned object is disposed.
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/// </summary>
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/// <param name="input">The stream to read from.</param>
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public CodedInputStream(Stream input) : this(input, false)
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{
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}
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/// <summary>
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/// Creates a new <see cref="CodedInputStream"/> reading data from the given stream.
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/// </summary>
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/// <param name="input">The stream to read from.</param>
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/// <param name="leaveOpen"><c>true</c> to leave <paramref name="input"/> open when the returned
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/// <c cref="CodedInputStream"/> is disposed; <c>false</c> to dispose of the given stream when the
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/// returned object is disposed.</param>
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public CodedInputStream(Stream input, bool leaveOpen)
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: this(ProtoPreconditions.CheckNotNull(input, "input"), new byte[BufferSize], 0, 0)
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{
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this.leaveOpen = leaveOpen;
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}
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/// <summary>
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/// Creates a new CodedInputStream reading data from the given
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/// stream and buffer, using the default limits.
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/// </summary>
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internal CodedInputStream(Stream input, byte[] buffer, int bufferPos, int bufferSize)
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{
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this.input = input;
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this.buffer = buffer;
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this.bufferPos = bufferPos;
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this.bufferSize = bufferSize;
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this.sizeLimit = DefaultSizeLimit;
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this.recursionLimit = DefaultRecursionLimit;
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}
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/// <summary>
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/// Creates a new CodedInputStream reading data from the given
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/// stream and buffer, using the specified limits.
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/// </summary>
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/// <remarks>
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/// This chains to the version with the default limits instead of vice versa to avoid
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/// having to check that the default values are valid every time.
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/// </remarks>
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internal CodedInputStream(Stream input, byte[] buffer, int bufferPos, int bufferSize, int sizeLimit, int recursionLimit)
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: this(input, buffer, bufferPos, bufferSize)
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{
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if (sizeLimit <= 0)
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{
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throw new ArgumentOutOfRangeException("sizeLimit", "Size limit must be positive");
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}
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if (recursionLimit <= 0)
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{
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throw new ArgumentOutOfRangeException("recursionLimit!", "Recursion limit must be positive");
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}
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this.sizeLimit = sizeLimit;
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this.recursionLimit = recursionLimit;
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}
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#endregion
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/// <summary>
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/// Creates a <see cref="CodedInputStream"/> with the specified size and recursion limits, reading
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/// from an input stream.
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/// </summary>
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/// <remarks>
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/// This method exists separately from the constructor to reduce the number of constructor overloads.
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/// It is likely to be used considerably less frequently than the constructors, as the default limits
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/// are suitable for most use cases.
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/// </remarks>
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/// <param name="input">The input stream to read from</param>
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/// <param name="sizeLimit">The total limit of data to read from the stream.</param>
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/// <param name="recursionLimit">The maximum recursion depth to allow while reading.</param>
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/// <returns>A <c>CodedInputStream</c> reading from <paramref name="input"/> with the specified size
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/// and recursion limits.</returns>
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public static CodedInputStream CreateWithLimits(Stream input, int sizeLimit, int recursionLimit)
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{
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return new CodedInputStream(input, new byte[BufferSize], 0, 0, sizeLimit, recursionLimit);
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}
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/// <summary>
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/// Returns the current position in the input stream, or the position in the input buffer
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/// </summary>
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public long Position
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{
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get
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{
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if (input != null)
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{
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return input.Position - ((bufferSize + bufferSizeAfterLimit) - bufferPos);
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}
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return bufferPos;
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}
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}
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/// <summary>
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/// Returns the last tag read, or 0 if no tags have been read or we've read beyond
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/// the end of the stream.
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/// </summary>
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internal uint LastTag { get { return lastTag; } }
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/// <summary>
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/// Returns the size limit for this stream.
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/// </summary>
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/// <remarks>
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/// This limit is applied when reading from the underlying stream, as a sanity check. It is
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/// not applied when reading from a byte array data source without an underlying stream.
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/// The default value is 64MB.
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/// </remarks>
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/// <value>
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/// The size limit.
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/// </value>
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public int SizeLimit { get { return sizeLimit; } }
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/// <summary>
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/// Returns the recursion limit for this stream. This limit is applied whilst reading messages,
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/// to avoid maliciously-recursive data.
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/// </summary>
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/// <remarks>
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/// The default limit is 64.
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/// </remarks>
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/// <value>
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/// The recursion limit for this stream.
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/// </value>
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public int RecursionLimit { get { return recursionLimit; } }
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/// <summary>
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/// Disposes of this instance, potentially closing any underlying stream.
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/// </summary>
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/// <remarks>
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/// As there is no flushing to perform here, disposing of a <see cref="CodedInputStream"/> which
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/// was constructed with the <c>leaveOpen</c> option parameter set to <c>true</c> (or one which
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/// was constructed to read from a byte array) has no effect.
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/// </remarks>
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public void Dispose()
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{
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if (!leaveOpen)
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{
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input.Dispose();
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}
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}
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#region Validation
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/// <summary>
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/// Verifies that the last call to ReadTag() returned tag 0 - in other words,
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/// we've reached the end of the stream when we expected to.
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/// </summary>
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/// <exception cref="InvalidProtocolBufferException">The
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/// tag read was not the one specified</exception>
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internal void CheckReadEndOfStreamTag()
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{
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if (lastTag != 0)
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{
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throw InvalidProtocolBufferException.MoreDataAvailable();
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}
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}
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#endregion
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#region Reading of tags etc
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/// <summary>
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/// Peeks at the next field tag. This is like calling <see cref="ReadTag"/>, but the
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/// tag is not consumed. (So a subsequent call to <see cref="ReadTag"/> will return the
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/// same value.)
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/// </summary>
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public uint PeekTag()
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{
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if (hasNextTag)
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{
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return nextTag;
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}
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uint savedLast = lastTag;
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nextTag = ReadTag();
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hasNextTag = true;
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lastTag = savedLast; // Undo the side effect of ReadTag
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return nextTag;
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}
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/// <summary>
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/// Reads a field tag, returning the tag of 0 for "end of stream".
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/// </summary>
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/// <remarks>
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/// If this method returns 0, it doesn't necessarily mean the end of all
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/// the data in this CodedInputStream; it may be the end of the logical stream
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/// for an embedded message, for example.
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/// </remarks>
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/// <returns>The next field tag, or 0 for end of stream. (0 is never a valid tag.)</returns>
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public uint ReadTag()
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{
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if (hasNextTag)
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{
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lastTag = nextTag;
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hasNextTag = false;
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return lastTag;
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}
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// Optimize for the incredibly common case of having at least two bytes left in the buffer,
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// and those two bytes being enough to get the tag. This will be true for fields up to 4095.
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if (bufferPos + 2 <= bufferSize)
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{
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int tmp = buffer[bufferPos++];
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if (tmp < 128)
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{
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lastTag = (uint)tmp;
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}
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else
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{
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int result = tmp & 0x7f;
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if ((tmp = buffer[bufferPos++]) < 128)
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{
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result |= tmp << 7;
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lastTag = (uint) result;
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}
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else
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{
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// Nope, rewind and go the potentially slow route.
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bufferPos -= 2;
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lastTag = ReadRawVarint32();
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}
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}
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}
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else
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{
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if (IsAtEnd)
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{
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lastTag = 0;
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return 0; // This is the only case in which we return 0.
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}
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lastTag = ReadRawVarint32();
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}
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if (lastTag == 0)
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{
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// If we actually read zero, that's not a valid tag.
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throw InvalidProtocolBufferException.InvalidTag();
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}
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return lastTag;
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}
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/// <summary>
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/// Skips the data for the field with the tag we've just read.
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/// This should be called directly after <see cref="ReadTag"/>, when
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/// the caller wishes to skip an unknown field.
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/// </summary>
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/// <remarks>
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/// This method throws <see cref="InvalidProtocolBufferException"/> if the last-read tag was an end-group tag.
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/// If a caller wishes to skip a group, they should skip the whole group, by calling this method after reading the
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/// start-group tag. This behavior allows callers to call this method on any field they don't understand, correctly
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/// resulting in an error if an end-group tag has not been paired with an earlier start-group tag.
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/// </remarks>
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/// <exception cref="InvalidProtocolBufferException">The last tag was an end-group tag</exception>
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/// <exception cref="InvalidOperationException">The last read operation read to the end of the logical stream</exception>
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public void SkipLastField()
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{
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if (lastTag == 0)
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{
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throw new InvalidOperationException("SkipLastField cannot be called at the end of a stream");
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}
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switch (WireFormat.GetTagWireType(lastTag))
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{
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case WireFormat.WireType.StartGroup:
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SkipGroup(lastTag);
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break;
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case WireFormat.WireType.EndGroup:
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throw new InvalidProtocolBufferException(
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"SkipLastField called on an end-group tag, indicating that the corresponding start-group was missing");
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case WireFormat.WireType.Fixed32:
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ReadFixed32();
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break;
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case WireFormat.WireType.Fixed64:
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ReadFixed64();
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break;
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case WireFormat.WireType.LengthDelimited:
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var length = ReadLength();
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SkipRawBytes(length);
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break;
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case WireFormat.WireType.Varint:
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ReadRawVarint32();
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break;
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}
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}
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private void SkipGroup(uint startGroupTag)
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{
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// Note: Currently we expect this to be the way that groups are read. We could put the recursion
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// depth changes into the ReadTag method instead, potentially...
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recursionDepth++;
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if (recursionDepth >= recursionLimit)
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{
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throw InvalidProtocolBufferException.RecursionLimitExceeded();
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}
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uint tag;
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while (true)
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{
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tag = ReadTag();
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if (tag == 0)
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{
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throw InvalidProtocolBufferException.TruncatedMessage();
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}
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// Can't call SkipLastField for this case- that would throw.
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if (WireFormat.GetTagWireType(tag) == WireFormat.WireType.EndGroup)
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{
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break;
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}
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// This recursion will allow us to handle nested groups.
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SkipLastField();
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}
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int startField = WireFormat.GetTagFieldNumber(startGroupTag);
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int endField = WireFormat.GetTagFieldNumber(tag);
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if (startField != endField)
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{
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throw new InvalidProtocolBufferException(
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$"Mismatched end-group tag. Started with field {startField}; ended with field {endField}");
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}
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recursionDepth--;
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}
|
|
|
|
/// <summary>
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/// Reads a double field from the stream.
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/// </summary>
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public double ReadDouble()
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{
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return BitConverter.Int64BitsToDouble((long) ReadRawLittleEndian64());
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}
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|
|
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/// <summary>
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/// Reads a float field from the stream.
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/// </summary>
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public float ReadFloat()
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{
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if (BitConverter.IsLittleEndian && 4 <= bufferSize - bufferPos)
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{
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float ret = BitConverter.ToSingle(buffer, bufferPos);
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bufferPos += 4;
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return ret;
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}
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else
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{
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byte[] rawBytes = ReadRawBytes(4);
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|
if (!BitConverter.IsLittleEndian)
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{
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|
ByteArray.Reverse(rawBytes);
|
|
}
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|
return BitConverter.ToSingle(rawBytes, 0);
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a uint64 field from the stream.
|
|
/// </summary>
|
|
public ulong ReadUInt64()
|
|
{
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return ReadRawVarint64();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an int64 field from the stream.
|
|
/// </summary>
|
|
public long ReadInt64()
|
|
{
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return (long) ReadRawVarint64();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an int32 field from the stream.
|
|
/// </summary>
|
|
public int ReadInt32()
|
|
{
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|
return (int) ReadRawVarint32();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a fixed64 field from the stream.
|
|
/// </summary>
|
|
public ulong ReadFixed64()
|
|
{
|
|
return ReadRawLittleEndian64();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a fixed32 field from the stream.
|
|
/// </summary>
|
|
public uint ReadFixed32()
|
|
{
|
|
return ReadRawLittleEndian32();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a bool field from the stream.
|
|
/// </summary>
|
|
public bool ReadBool()
|
|
{
|
|
return ReadRawVarint32() != 0;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a string field from the stream.
|
|
/// </summary>
|
|
public string ReadString()
|
|
{
|
|
int length = ReadLength();
|
|
// No need to read any data for an empty string.
|
|
if (length == 0)
|
|
{
|
|
return "";
|
|
}
|
|
if (length <= bufferSize - bufferPos)
|
|
{
|
|
// Fast path: We already have the bytes in a contiguous buffer, so
|
|
// just copy directly from it.
|
|
String result = CodedOutputStream.Utf8Encoding.GetString(buffer, bufferPos, length);
|
|
bufferPos += length;
|
|
return result;
|
|
}
|
|
// Slow path: Build a byte array first then copy it.
|
|
return CodedOutputStream.Utf8Encoding.GetString(ReadRawBytes(length), 0, length);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an embedded message field value from the stream.
|
|
/// </summary>
|
|
public void ReadMessage(IMessage builder)
|
|
{
|
|
int length = ReadLength();
|
|
if (recursionDepth >= recursionLimit)
|
|
{
|
|
throw InvalidProtocolBufferException.RecursionLimitExceeded();
|
|
}
|
|
int oldLimit = PushLimit(length);
|
|
++recursionDepth;
|
|
builder.MergeFrom(this);
|
|
CheckReadEndOfStreamTag();
|
|
// Check that we've read exactly as much data as expected.
|
|
if (!ReachedLimit)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
--recursionDepth;
|
|
PopLimit(oldLimit);
|
|
}
|
|
public ushort ReadUShort()
|
|
{
|
|
int tmp = buffer[bufferPos++];
|
|
int result = tmp & 0x7f;
|
|
tmp = buffer[bufferPos++];
|
|
result |= tmp << 7;
|
|
return (ushort)result;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a bytes field value from the stream.
|
|
/// </summary>
|
|
public ByteString ReadBytes()
|
|
{
|
|
int length = ReadLength();
|
|
if (length <= bufferSize - bufferPos && length > 0)
|
|
{
|
|
// Fast path: We already have the bytes in a contiguous buffer, so
|
|
// just copy directly from it.
|
|
ByteString result = ByteString.CopyFrom(buffer, bufferPos, length);
|
|
bufferPos += length;
|
|
return result;
|
|
}
|
|
else
|
|
{
|
|
// Slow path: Build a byte array and attach it to a new ByteString.
|
|
return ByteString.AttachBytes(ReadRawBytes(length));
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a uint32 field value from the stream.
|
|
/// </summary>
|
|
public uint ReadUInt32()
|
|
{
|
|
return ReadRawVarint32();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an enum field value from the stream. If the enum is valid for type T,
|
|
/// then the ref value is set and it returns true. Otherwise the unknown output
|
|
/// value is set and this method returns false.
|
|
/// </summary>
|
|
public int ReadEnum()
|
|
{
|
|
// Currently just a pass-through, but it's nice to separate it logically from WriteInt32.
|
|
return (int) ReadRawVarint32();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an sfixed32 field value from the stream.
|
|
/// </summary>
|
|
public int ReadSFixed32()
|
|
{
|
|
return (int) ReadRawLittleEndian32();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an sfixed64 field value from the stream.
|
|
/// </summary>
|
|
public long ReadSFixed64()
|
|
{
|
|
return (long) ReadRawLittleEndian64();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an sint32 field value from the stream.
|
|
/// </summary>
|
|
public int ReadSInt32()
|
|
{
|
|
return DecodeZigZag32(ReadRawVarint32());
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads an sint64 field value from the stream.
|
|
/// </summary>
|
|
public long ReadSInt64()
|
|
{
|
|
return DecodeZigZag64(ReadRawVarint64());
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a length for length-delimited data.
|
|
/// </summary>
|
|
/// <remarks>
|
|
/// This is internally just reading a varint, but this method exists
|
|
/// to make the calling code clearer.
|
|
/// </remarks>
|
|
public int ReadLength()
|
|
{
|
|
return (int) ReadRawVarint32();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Peeks at the next tag in the stream. If it matches <paramref name="tag"/>,
|
|
/// the tag is consumed and the method returns <c>true</c>; otherwise, the
|
|
/// stream is left in the original position and the method returns <c>false</c>.
|
|
/// </summary>
|
|
public bool MaybeConsumeTag(uint tag)
|
|
{
|
|
if (PeekTag() == tag)
|
|
{
|
|
hasNextTag = false;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region Underlying reading primitives
|
|
|
|
/// <summary>
|
|
/// Same code as ReadRawVarint32, but read each byte individually, checking for
|
|
/// buffer overflow.
|
|
/// </summary>
|
|
private uint SlowReadRawVarint32()
|
|
{
|
|
int tmp = ReadRawByte();
|
|
if (tmp < 128)
|
|
{
|
|
return (uint) tmp;
|
|
}
|
|
int result = tmp & 0x7f;
|
|
if ((tmp = ReadRawByte()) < 128)
|
|
{
|
|
result |= tmp << 7;
|
|
}
|
|
else
|
|
{
|
|
result |= (tmp & 0x7f) << 7;
|
|
if ((tmp = ReadRawByte()) < 128)
|
|
{
|
|
result |= tmp << 14;
|
|
}
|
|
else
|
|
{
|
|
result |= (tmp & 0x7f) << 14;
|
|
if ((tmp = ReadRawByte()) < 128)
|
|
{
|
|
result |= tmp << 21;
|
|
}
|
|
else
|
|
{
|
|
result |= (tmp & 0x7f) << 21;
|
|
result |= (tmp = ReadRawByte()) << 28;
|
|
if (tmp >= 128)
|
|
{
|
|
// Discard upper 32 bits.
|
|
for (int i = 0; i < 5; i++)
|
|
{
|
|
if (ReadRawByte() < 128)
|
|
{
|
|
return (uint) result;
|
|
}
|
|
}
|
|
throw InvalidProtocolBufferException.MalformedVarint();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return (uint) result;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a raw Varint from the stream. If larger than 32 bits, discard the upper bits.
|
|
/// This method is optimised for the case where we've got lots of data in the buffer.
|
|
/// That means we can check the size just once, then just read directly from the buffer
|
|
/// without constant rechecking of the buffer length.
|
|
/// </summary>
|
|
internal uint ReadRawVarint32()
|
|
{
|
|
if (bufferPos + 5 > bufferSize)
|
|
{
|
|
return SlowReadRawVarint32();
|
|
}
|
|
|
|
int tmp = buffer[bufferPos++];
|
|
if (tmp < 128)
|
|
{
|
|
return (uint) tmp;
|
|
}
|
|
int result = tmp & 0x7f;
|
|
if ((tmp = buffer[bufferPos++]) < 128)
|
|
{
|
|
result |= tmp << 7;
|
|
}
|
|
else
|
|
{
|
|
result |= (tmp & 0x7f) << 7;
|
|
if ((tmp = buffer[bufferPos++]) < 128)
|
|
{
|
|
result |= tmp << 14;
|
|
}
|
|
else
|
|
{
|
|
result |= (tmp & 0x7f) << 14;
|
|
if ((tmp = buffer[bufferPos++]) < 128)
|
|
{
|
|
result |= tmp << 21;
|
|
}
|
|
else
|
|
{
|
|
result |= (tmp & 0x7f) << 21;
|
|
result |= (tmp = buffer[bufferPos++]) << 28;
|
|
if (tmp >= 128)
|
|
{
|
|
// Discard upper 32 bits.
|
|
// Note that this has to use ReadRawByte() as we only ensure we've
|
|
// got at least 5 bytes at the start of the method. This lets us
|
|
// use the fast path in more cases, and we rarely hit this section of code.
|
|
for (int i = 0; i < 5; i++)
|
|
{
|
|
if (ReadRawByte() < 128)
|
|
{
|
|
return (uint) result;
|
|
}
|
|
}
|
|
throw InvalidProtocolBufferException.MalformedVarint();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return (uint) result;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a varint from the input one byte at a time, so that it does not
|
|
/// read any bytes after the end of the varint. If you simply wrapped the
|
|
/// stream in a CodedInputStream and used ReadRawVarint32(Stream)
|
|
/// then you would probably end up reading past the end of the varint since
|
|
/// CodedInputStream buffers its input.
|
|
/// </summary>
|
|
/// <param name="input"></param>
|
|
/// <returns></returns>
|
|
internal static uint ReadRawVarint32(Stream input)
|
|
{
|
|
int result = 0;
|
|
int offset = 0;
|
|
for (; offset < 32; offset += 7)
|
|
{
|
|
int b = input.ReadByte();
|
|
if (b == -1)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
result |= (b & 0x7f) << offset;
|
|
if ((b & 0x80) == 0)
|
|
{
|
|
return (uint) result;
|
|
}
|
|
}
|
|
// Keep reading up to 64 bits.
|
|
for (; offset < 64; offset += 7)
|
|
{
|
|
int b = input.ReadByte();
|
|
if (b == -1)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
if ((b & 0x80) == 0)
|
|
{
|
|
return (uint) result;
|
|
}
|
|
}
|
|
throw InvalidProtocolBufferException.MalformedVarint();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a raw varint from the stream.
|
|
/// </summary>
|
|
internal ulong ReadRawVarint64()
|
|
{
|
|
int shift = 0;
|
|
ulong result = 0;
|
|
while (shift < 64)
|
|
{
|
|
byte b = ReadRawByte();
|
|
result |= (ulong) (b & 0x7F) << shift;
|
|
if ((b & 0x80) == 0)
|
|
{
|
|
return result;
|
|
}
|
|
shift += 7;
|
|
}
|
|
throw InvalidProtocolBufferException.MalformedVarint();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a 32-bit little-endian integer from the stream.
|
|
/// </summary>
|
|
internal uint ReadRawLittleEndian32()
|
|
{
|
|
uint b1 = ReadRawByte();
|
|
uint b2 = ReadRawByte();
|
|
uint b3 = ReadRawByte();
|
|
uint b4 = ReadRawByte();
|
|
return b1 | (b2 << 8) | (b3 << 16) | (b4 << 24);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a 64-bit little-endian integer from the stream.
|
|
/// </summary>
|
|
internal ulong ReadRawLittleEndian64()
|
|
{
|
|
ulong b1 = ReadRawByte();
|
|
ulong b2 = ReadRawByte();
|
|
ulong b3 = ReadRawByte();
|
|
ulong b4 = ReadRawByte();
|
|
ulong b5 = ReadRawByte();
|
|
ulong b6 = ReadRawByte();
|
|
ulong b7 = ReadRawByte();
|
|
ulong b8 = ReadRawByte();
|
|
return b1 | (b2 << 8) | (b3 << 16) | (b4 << 24)
|
|
| (b5 << 32) | (b6 << 40) | (b7 << 48) | (b8 << 56);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Decode a 32-bit value with ZigZag encoding.
|
|
/// </summary>
|
|
/// <remarks>
|
|
/// ZigZag encodes signed integers into values that can be efficiently
|
|
/// encoded with varint. (Otherwise, negative values must be
|
|
/// sign-extended to 64 bits to be varint encoded, thus always taking
|
|
/// 10 bytes on the wire.)
|
|
/// </remarks>
|
|
internal static int DecodeZigZag32(uint n)
|
|
{
|
|
return (int)(n >> 1) ^ -(int)(n & 1);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Decode a 32-bit value with ZigZag encoding.
|
|
/// </summary>
|
|
/// <remarks>
|
|
/// ZigZag encodes signed integers into values that can be efficiently
|
|
/// encoded with varint. (Otherwise, negative values must be
|
|
/// sign-extended to 64 bits to be varint encoded, thus always taking
|
|
/// 10 bytes on the wire.)
|
|
/// </remarks>
|
|
internal static long DecodeZigZag64(ulong n)
|
|
{
|
|
return (long)(n >> 1) ^ -(long)(n & 1);
|
|
}
|
|
#endregion
|
|
|
|
#region Internal reading and buffer management
|
|
|
|
/// <summary>
|
|
/// Sets currentLimit to (current position) + byteLimit. This is called
|
|
/// when descending into a length-delimited embedded message. The previous
|
|
/// limit is returned.
|
|
/// </summary>
|
|
/// <returns>The old limit.</returns>
|
|
internal int PushLimit(int byteLimit)
|
|
{
|
|
if (byteLimit < 0)
|
|
{
|
|
throw InvalidProtocolBufferException.NegativeSize();
|
|
}
|
|
byteLimit += totalBytesRetired + bufferPos;
|
|
int oldLimit = currentLimit;
|
|
if (byteLimit > oldLimit)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
currentLimit = byteLimit;
|
|
|
|
RecomputeBufferSizeAfterLimit();
|
|
|
|
return oldLimit;
|
|
}
|
|
|
|
private void RecomputeBufferSizeAfterLimit()
|
|
{
|
|
bufferSize += bufferSizeAfterLimit;
|
|
int bufferEnd = totalBytesRetired + bufferSize;
|
|
if (bufferEnd > currentLimit)
|
|
{
|
|
// Limit is in current buffer.
|
|
bufferSizeAfterLimit = bufferEnd - currentLimit;
|
|
bufferSize -= bufferSizeAfterLimit;
|
|
}
|
|
else
|
|
{
|
|
bufferSizeAfterLimit = 0;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Discards the current limit, returning the previous limit.
|
|
/// </summary>
|
|
internal void PopLimit(int oldLimit)
|
|
{
|
|
currentLimit = oldLimit;
|
|
RecomputeBufferSizeAfterLimit();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Returns whether or not all the data before the limit has been read.
|
|
/// </summary>
|
|
/// <returns></returns>
|
|
internal bool ReachedLimit
|
|
{
|
|
get
|
|
{
|
|
if (currentLimit == int.MaxValue)
|
|
{
|
|
return false;
|
|
}
|
|
int currentAbsolutePosition = totalBytesRetired + bufferPos;
|
|
return currentAbsolutePosition >= currentLimit;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Returns true if the stream has reached the end of the input. This is the
|
|
/// case if either the end of the underlying input source has been reached or
|
|
/// the stream has reached a limit created using PushLimit.
|
|
/// </summary>
|
|
public bool IsAtEnd
|
|
{
|
|
get { return bufferPos == bufferSize && !RefillBuffer(false); }
|
|
}
|
|
|
|
/// <summary>
|
|
/// Called when buffer is empty to read more bytes from the
|
|
/// input. If <paramref name="mustSucceed"/> is true, RefillBuffer() gurantees that
|
|
/// either there will be at least one byte in the buffer when it returns
|
|
/// or it will throw an exception. If <paramref name="mustSucceed"/> is false,
|
|
/// RefillBuffer() returns false if no more bytes were available.
|
|
/// </summary>
|
|
/// <param name="mustSucceed"></param>
|
|
/// <returns></returns>
|
|
private bool RefillBuffer(bool mustSucceed)
|
|
{
|
|
if (bufferPos < bufferSize)
|
|
{
|
|
throw new InvalidOperationException("RefillBuffer() called when buffer wasn't empty.");
|
|
}
|
|
|
|
if (totalBytesRetired + bufferSize == currentLimit)
|
|
{
|
|
// Oops, we hit a limit.
|
|
if (mustSucceed)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
totalBytesRetired += bufferSize;
|
|
|
|
bufferPos = 0;
|
|
bufferSize = (input == null) ? 0 : input.Read(buffer, 0, buffer.Length);
|
|
if (bufferSize < 0)
|
|
{
|
|
throw new InvalidOperationException("Stream.Read returned a negative count");
|
|
}
|
|
if (bufferSize == 0)
|
|
{
|
|
if (mustSucceed)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
RecomputeBufferSizeAfterLimit();
|
|
int totalBytesRead =
|
|
totalBytesRetired + bufferSize + bufferSizeAfterLimit;
|
|
if (totalBytesRead > sizeLimit || totalBytesRead < 0)
|
|
{
|
|
throw InvalidProtocolBufferException.SizeLimitExceeded();
|
|
}
|
|
return true;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Read one byte from the input.
|
|
/// </summary>
|
|
/// <exception cref="InvalidProtocolBufferException">
|
|
/// the end of the stream or the current limit was reached
|
|
/// </exception>
|
|
internal byte ReadRawByte()
|
|
{
|
|
if (bufferPos == bufferSize)
|
|
{
|
|
RefillBuffer(true);
|
|
}
|
|
return buffer[bufferPos++];
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads a fixed size of bytes from the input.
|
|
/// </summary>
|
|
/// <exception cref="InvalidProtocolBufferException">
|
|
/// the end of the stream or the current limit was reached
|
|
/// </exception>
|
|
internal byte[] ReadRawBytes(int size)
|
|
{
|
|
if (size < 0)
|
|
{
|
|
throw InvalidProtocolBufferException.NegativeSize();
|
|
}
|
|
|
|
if (totalBytesRetired + bufferPos + size > currentLimit)
|
|
{
|
|
// Read to the end of the stream (up to the current limit) anyway.
|
|
SkipRawBytes(currentLimit - totalBytesRetired - bufferPos);
|
|
// Then fail.
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
|
|
if (size <= bufferSize - bufferPos)
|
|
{
|
|
// We have all the bytes we need already.
|
|
byte[] bytes = new byte[size];
|
|
ByteArray.Copy(buffer, bufferPos, bytes, 0, size);
|
|
bufferPos += size;
|
|
return bytes;
|
|
}
|
|
else if (size < buffer.Length)
|
|
{
|
|
// Reading more bytes than are in the buffer, but not an excessive number
|
|
// of bytes. We can safely allocate the resulting array ahead of time.
|
|
|
|
// First copy what we have.
|
|
byte[] bytes = new byte[size];
|
|
int pos = bufferSize - bufferPos;
|
|
ByteArray.Copy(buffer, bufferPos, bytes, 0, pos);
|
|
bufferPos = bufferSize;
|
|
|
|
// We want to use RefillBuffer() and then copy from the buffer into our
|
|
// byte array rather than reading directly into our byte array because
|
|
// the input may be unbuffered.
|
|
RefillBuffer(true);
|
|
|
|
while (size - pos > bufferSize)
|
|
{
|
|
Buffer.BlockCopy(buffer, 0, bytes, pos, bufferSize);
|
|
pos += bufferSize;
|
|
bufferPos = bufferSize;
|
|
RefillBuffer(true);
|
|
}
|
|
|
|
ByteArray.Copy(buffer, 0, bytes, pos, size - pos);
|
|
bufferPos = size - pos;
|
|
|
|
return bytes;
|
|
}
|
|
else
|
|
{
|
|
// The size is very large. For security reasons, we can't allocate the
|
|
// entire byte array yet. The size comes directly from the input, so a
|
|
// maliciously-crafted message could provide a bogus very large size in
|
|
// order to trick the app into allocating a lot of memory. We avoid this
|
|
// by allocating and reading only a small chunk at a time, so that the
|
|
// malicious message must actually *be* extremely large to cause
|
|
// problems. Meanwhile, we limit the allowed size of a message elsewhere.
|
|
|
|
// Remember the buffer markers since we'll have to copy the bytes out of
|
|
// it later.
|
|
int originalBufferPos = bufferPos;
|
|
int originalBufferSize = bufferSize;
|
|
|
|
// Mark the current buffer consumed.
|
|
totalBytesRetired += bufferSize;
|
|
bufferPos = 0;
|
|
bufferSize = 0;
|
|
|
|
// Read all the rest of the bytes we need.
|
|
int sizeLeft = size - (originalBufferSize - originalBufferPos);
|
|
List<byte[]> chunks = new List<byte[]>();
|
|
|
|
while (sizeLeft > 0)
|
|
{
|
|
byte[] chunk = new byte[Math.Min(sizeLeft, buffer.Length)];
|
|
int pos = 0;
|
|
while (pos < chunk.Length)
|
|
{
|
|
int n = (input == null) ? -1 : input.Read(chunk, pos, chunk.Length - pos);
|
|
if (n <= 0)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
totalBytesRetired += n;
|
|
pos += n;
|
|
}
|
|
sizeLeft -= chunk.Length;
|
|
chunks.Add(chunk);
|
|
}
|
|
|
|
// OK, got everything. Now concatenate it all into one buffer.
|
|
byte[] bytes = new byte[size];
|
|
|
|
// Start by copying the leftover bytes from this.buffer.
|
|
int newPos = originalBufferSize - originalBufferPos;
|
|
ByteArray.Copy(buffer, originalBufferPos, bytes, 0, newPos);
|
|
|
|
// And now all the chunks.
|
|
foreach (byte[] chunk in chunks)
|
|
{
|
|
Buffer.BlockCopy(chunk, 0, bytes, newPos, chunk.Length);
|
|
newPos += chunk.Length;
|
|
}
|
|
|
|
// Done.
|
|
return bytes;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Reads and discards <paramref name="size"/> bytes.
|
|
/// </summary>
|
|
/// <exception cref="InvalidProtocolBufferException">the end of the stream
|
|
/// or the current limit was reached</exception>
|
|
private void SkipRawBytes(int size)
|
|
{
|
|
if (size < 0)
|
|
{
|
|
throw InvalidProtocolBufferException.NegativeSize();
|
|
}
|
|
|
|
if (totalBytesRetired + bufferPos + size > currentLimit)
|
|
{
|
|
// Read to the end of the stream anyway.
|
|
SkipRawBytes(currentLimit - totalBytesRetired - bufferPos);
|
|
// Then fail.
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
|
|
if (size <= bufferSize - bufferPos)
|
|
{
|
|
// We have all the bytes we need already.
|
|
bufferPos += size;
|
|
}
|
|
else
|
|
{
|
|
// Skipping more bytes than are in the buffer. First skip what we have.
|
|
int pos = bufferSize - bufferPos;
|
|
|
|
// ROK 5/7/2013 Issue #54: should retire all bytes in buffer (bufferSize)
|
|
// totalBytesRetired += pos;
|
|
totalBytesRetired += bufferSize;
|
|
|
|
bufferPos = 0;
|
|
bufferSize = 0;
|
|
|
|
// Then skip directly from the InputStream for the rest.
|
|
if (pos < size)
|
|
{
|
|
if (input == null)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
SkipImpl(size - pos);
|
|
totalBytesRetired += size - pos;
|
|
}
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Abstraction of skipping to cope with streams which can't really skip.
|
|
/// </summary>
|
|
private void SkipImpl(int amountToSkip)
|
|
{
|
|
if (input.CanSeek)
|
|
{
|
|
long previousPosition = input.Position;
|
|
input.Position += amountToSkip;
|
|
if (input.Position != previousPosition + amountToSkip)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
byte[] skipBuffer = new byte[Math.Min(1024, amountToSkip)];
|
|
while (amountToSkip > 0)
|
|
{
|
|
int bytesRead = input.Read(skipBuffer, 0, Math.Min(skipBuffer.Length, amountToSkip));
|
|
if (bytesRead <= 0)
|
|
{
|
|
throw InvalidProtocolBufferException.TruncatedMessage();
|
|
}
|
|
amountToSkip -= bytesRead;
|
|
}
|
|
}
|
|
}
|
|
|
|
#endregion
|
|
}
|
|
}
|