Squashed 'third_party/protobuf/' content from commit e35e248
Change-Id: I6cbe123d09fe50fdcad0e51466665daeee7433c7
git-subtree-dir: third_party/protobuf
git-subtree-split: e35e24800fb8d694bdeea5fd63dc7d1b14d68723
diff --git a/csharp/src/Google.Protobuf/CodedInputStream.cs b/csharp/src/Google.Protobuf/CodedInputStream.cs
new file mode 100644
index 0000000..91bed8e
--- /dev/null
+++ b/csharp/src/Google.Protobuf/CodedInputStream.cs
@@ -0,0 +1,1221 @@
+#region Copyright notice and license
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc. All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#endregion
+
+using Google.Protobuf.Collections;
+using System;
+using System.Collections.Generic;
+using System.IO;
+
+namespace Google.Protobuf
+{
+ /// <summary>
+ /// Reads and decodes protocol message fields.
+ /// </summary>
+ /// <remarks>
+ /// <para>
+ /// This class is generally used by generated code to read appropriate
+ /// primitives from the stream. It effectively encapsulates the lowest
+ /// levels of protocol buffer format.
+ /// </para>
+ /// <para>
+ /// Repeated fields and map fields are not handled by this class; use <see cref="RepeatedField{T}"/>
+ /// and <see cref="MapField{TKey, TValue}"/> to serialize such fields.
+ /// </para>
+ /// </remarks>
+ public sealed class CodedInputStream
+ {
+ /// <summary>
+ /// Buffer of data read from the stream or provided at construction time.
+ /// </summary>
+ private readonly byte[] buffer;
+
+ /// <summary>
+ /// The index of the buffer at which we need to refill from the stream (if there is one).
+ /// </summary>
+ private int bufferSize;
+
+ private int bufferSizeAfterLimit = 0;
+ /// <summary>
+ /// The position within the current buffer (i.e. the next byte to read)
+ /// </summary>
+ private int bufferPos = 0;
+
+ /// <summary>
+ /// The stream to read further input from, or null if the byte array buffer was provided
+ /// directly on construction, with no further data available.
+ /// </summary>
+ private readonly Stream input;
+
+ /// <summary>
+ /// The last tag we read. 0 indicates we've read to the end of the stream
+ /// (or haven't read anything yet).
+ /// </summary>
+ private uint lastTag = 0;
+
+ /// <summary>
+ /// The next tag, used to store the value read by PeekTag.
+ /// </summary>
+ private uint nextTag = 0;
+ private bool hasNextTag = false;
+
+ internal const int DefaultRecursionLimit = 64;
+ internal const int DefaultSizeLimit = 64 << 20; // 64MB
+ internal const int BufferSize = 4096;
+
+ /// <summary>
+ /// The total number of bytes read before the current buffer. The
+ /// total bytes read up to the current position can be computed as
+ /// totalBytesRetired + bufferPos.
+ /// </summary>
+ private int totalBytesRetired = 0;
+
+ /// <summary>
+ /// The absolute position of the end of the current message.
+ /// </summary>
+ private int currentLimit = int.MaxValue;
+
+ private int recursionDepth = 0;
+
+ private readonly int recursionLimit;
+ private readonly int sizeLimit;
+
+ #region Construction
+ // Note that the checks are performed such that we don't end up checking obviously-valid things
+ // like non-null references for arrays we've just created.
+
+ /// <summary>
+ /// Creates a new CodedInputStream reading data from the given byte array.
+ /// </summary>
+ public CodedInputStream(byte[] buffer) : this(null, ProtoPreconditions.CheckNotNull(buffer, "buffer"), 0, buffer.Length)
+ {
+ }
+
+ /// <summary>
+ /// Creates a new CodedInputStream that reads from the given byte array slice.
+ /// </summary>
+ public CodedInputStream(byte[] buffer, int offset, int length)
+ : this(null, ProtoPreconditions.CheckNotNull(buffer, "buffer"), offset, offset + length)
+ {
+ if (offset < 0 || offset > buffer.Length)
+ {
+ throw new ArgumentOutOfRangeException("offset", "Offset must be within the buffer");
+ }
+ if (length < 0 || offset + length > buffer.Length)
+ {
+ throw new ArgumentOutOfRangeException("length", "Length must be non-negative and within the buffer");
+ }
+ }
+
+ /// <summary>
+ /// Creates a new CodedInputStream reading data from the given stream.
+ /// </summary>
+ public CodedInputStream(Stream input) : this(input, new byte[BufferSize], 0, 0)
+ {
+ ProtoPreconditions.CheckNotNull(input, "input");
+ }
+
+ /// <summary>
+ /// Creates a new CodedInputStream reading data from the given
+ /// stream and buffer, using the default limits.
+ /// </summary>
+ internal CodedInputStream(Stream input, byte[] buffer, int bufferPos, int bufferSize)
+ {
+ this.input = input;
+ this.buffer = buffer;
+ this.bufferPos = bufferPos;
+ this.bufferSize = bufferSize;
+ this.sizeLimit = DefaultSizeLimit;
+ this.recursionLimit = DefaultRecursionLimit;
+ }
+
+ /// <summary>
+ /// Creates a new CodedInputStream reading data from the given
+ /// stream and buffer, using the specified limits.
+ /// </summary>
+ /// <remarks>
+ /// This chains to the version with the default limits instead of vice versa to avoid
+ /// having to check that the default values are valid every time.
+ /// </remarks>
+ internal CodedInputStream(Stream input, byte[] buffer, int bufferPos, int bufferSize, int sizeLimit, int recursionLimit)
+ : this(input, buffer, bufferPos, bufferSize)
+ {
+ if (sizeLimit <= 0)
+ {
+ throw new ArgumentOutOfRangeException("sizeLimit", "Size limit must be positive");
+ }
+ if (recursionLimit <= 0)
+ {
+ throw new ArgumentOutOfRangeException("recursionLimit!", "Recursion limit must be positive");
+ }
+ this.sizeLimit = sizeLimit;
+ this.recursionLimit = recursionLimit;
+ }
+ #endregion
+
+ /// <summary>
+ /// Creates a <see cref="CodedInputStream"/> with the specified size and recursion limits, reading
+ /// from an input stream.
+ /// </summary>
+ /// <remarks>
+ /// This method exists separately from the constructor to reduce the number of constructor overloads.
+ /// It is likely to be used considerably less frequently than the constructors, as the default limits
+ /// are suitable for most use cases.
+ /// </remarks>
+ /// <param name="input">The input stream to read from</param>
+ /// <param name="sizeLimit">The total limit of data to read from the stream.</param>
+ /// <param name="recursionLimit">The maximum recursion depth to allow while reading.</param>
+ /// <returns>A <c>CodedInputStream</c> reading from <paramref name="input"/> with the specified size
+ /// and recursion limits.</returns>
+ public static CodedInputStream CreateWithLimits(Stream input, int sizeLimit, int recursionLimit)
+ {
+ return new CodedInputStream(input, new byte[BufferSize], 0, 0, sizeLimit, recursionLimit);
+ }
+
+ /// <summary>
+ /// Returns the current position in the input stream, or the position in the input buffer
+ /// </summary>
+ public long Position
+ {
+ get
+ {
+ if (input != null)
+ {
+ return input.Position - ((bufferSize + bufferSizeAfterLimit) - bufferPos);
+ }
+ return bufferPos;
+ }
+ }
+
+ /// <summary>
+ /// Returns the last tag read, or 0 if no tags have been read or we've read beyond
+ /// the end of the stream.
+ /// </summary>
+ internal uint LastTag { get { return lastTag; } }
+
+ /// <summary>
+ /// Returns the size limit for this stream.
+ /// </summary>
+ /// <remarks>
+ /// This limit is applied when reading from the underlying stream, as a sanity check. It is
+ /// not applied when reading from a byte array data source without an underlying stream.
+ /// The default value is 64MB.
+ /// </remarks>
+ /// <value>
+ /// The size limit.
+ /// </value>
+ public int SizeLimit { get { return sizeLimit; } }
+
+ /// <summary>
+ /// Returns the recursion limit for this stream. This limit is applied whilst reading messages,
+ /// to avoid maliciously-recursive data.
+ /// </summary>
+ /// <remarks>
+ /// The default limit is 64.
+ /// </remarks>
+ /// <value>
+ /// The recursion limit for this stream.
+ /// </value>
+ public int RecursionLimit { get { return recursionLimit; } }
+
+ #region Validation
+ /// <summary>
+ /// Verifies that the last call to ReadTag() returned tag 0 - in other words,
+ /// we've reached the end of the stream when we expected to.
+ /// </summary>
+ /// <exception cref="InvalidProtocolBufferException">The
+ /// tag read was not the one specified</exception>
+ internal void CheckReadEndOfStreamTag()
+ {
+ if (lastTag != 0)
+ {
+ throw InvalidProtocolBufferException.MoreDataAvailable();
+ }
+ }
+ #endregion
+
+ #region Reading of tags etc
+
+ /// <summary>
+ /// Peeks at the next field tag. This is like calling <see cref="ReadTag"/>, but the
+ /// tag is not consumed. (So a subsequent call to <see cref="ReadTag"/> will return the
+ /// same value.)
+ /// </summary>
+ public uint PeekTag()
+ {
+ if (hasNextTag)
+ {
+ return nextTag;
+ }
+
+ uint savedLast = lastTag;
+ nextTag = ReadTag();
+ hasNextTag = true;
+ lastTag = savedLast; // Undo the side effect of ReadTag
+ return nextTag;
+ }
+
+ /// <summary>
+ /// Reads a field tag, returning the tag of 0 for "end of stream".
+ /// </summary>
+ /// <remarks>
+ /// If this method returns 0, it doesn't necessarily mean the end of all
+ /// the data in this CodedInputStream; it may be the end of the logical stream
+ /// for an embedded message, for example.
+ /// </remarks>
+ /// <returns>The next field tag, or 0 for end of stream. (0 is never a valid tag.)</returns>
+ public uint ReadTag()
+ {
+ if (hasNextTag)
+ {
+ lastTag = nextTag;
+ hasNextTag = false;
+ return lastTag;
+ }
+
+ // Optimize for the incredibly common case of having at least two bytes left in the buffer,
+ // and those two bytes being enough to get the tag. This will be true for fields up to 4095.
+ if (bufferPos + 2 <= bufferSize)
+ {
+ int tmp = buffer[bufferPos++];
+ if (tmp < 128)
+ {
+ lastTag = (uint)tmp;
+ }
+ else
+ {
+ int result = tmp & 0x7f;
+ if ((tmp = buffer[bufferPos++]) < 128)
+ {
+ result |= tmp << 7;
+ lastTag = (uint) result;
+ }
+ else
+ {
+ // Nope, rewind and go the potentially slow route.
+ bufferPos -= 2;
+ lastTag = ReadRawVarint32();
+ }
+ }
+ }
+ else
+ {
+ if (IsAtEnd)
+ {
+ lastTag = 0;
+ return 0; // This is the only case in which we return 0.
+ }
+
+ lastTag = ReadRawVarint32();
+ }
+ if (lastTag == 0)
+ {
+ // If we actually read zero, that's not a valid tag.
+ throw InvalidProtocolBufferException.InvalidTag();
+ }
+ return lastTag;
+ }
+
+ /// <summary>
+ /// Skips the data for the field with the tag we've just read.
+ /// This should be called directly after <see cref="ReadTag"/>, when
+ /// the caller wishes to skip an unknown field.
+ /// </summary>
+ public void SkipLastField()
+ {
+ if (lastTag == 0)
+ {
+ throw new InvalidOperationException("SkipLastField cannot be called at the end of a stream");
+ }
+ switch (WireFormat.GetTagWireType(lastTag))
+ {
+ case WireFormat.WireType.StartGroup:
+ SkipGroup();
+ break;
+ case WireFormat.WireType.EndGroup:
+ // Just ignore; there's no data following the tag.
+ break;
+ case WireFormat.WireType.Fixed32:
+ ReadFixed32();
+ break;
+ case WireFormat.WireType.Fixed64:
+ ReadFixed64();
+ break;
+ case WireFormat.WireType.LengthDelimited:
+ var length = ReadLength();
+ SkipRawBytes(length);
+ break;
+ case WireFormat.WireType.Varint:
+ ReadRawVarint32();
+ break;
+ }
+ }
+
+ private void SkipGroup()
+ {
+ // Note: Currently we expect this to be the way that groups are read. We could put the recursion
+ // depth changes into the ReadTag method instead, potentially...
+ recursionDepth++;
+ if (recursionDepth >= recursionLimit)
+ {
+ throw InvalidProtocolBufferException.RecursionLimitExceeded();
+ }
+ uint tag;
+ do
+ {
+ tag = ReadTag();
+ if (tag == 0)
+ {
+ throw InvalidProtocolBufferException.TruncatedMessage();
+ }
+ // This recursion will allow us to handle nested groups.
+ SkipLastField();
+ } while (WireFormat.GetTagWireType(tag) != WireFormat.WireType.EndGroup);
+ recursionDepth--;
+ }
+
+ /// <summary>
+ /// Reads a double field from the stream.
+ /// </summary>
+ public double ReadDouble()
+ {
+ return BitConverter.Int64BitsToDouble((long) ReadRawLittleEndian64());
+ }
+
+ /// <summary>
+ /// Reads a float field from the stream.
+ /// </summary>
+ public float ReadFloat()
+ {
+ if (BitConverter.IsLittleEndian && 4 <= bufferSize - bufferPos)
+ {
+ float ret = BitConverter.ToSingle(buffer, bufferPos);
+ bufferPos += 4;
+ return ret;
+ }
+ else
+ {
+ byte[] rawBytes = ReadRawBytes(4);
+ if (!BitConverter.IsLittleEndian)
+ {
+ ByteArray.Reverse(rawBytes);
+ }
+ return BitConverter.ToSingle(rawBytes, 0);
+ }
+ }
+
+ /// <summary>
+ /// Reads a uint64 field from the stream.
+ /// </summary>
+ public ulong ReadUInt64()
+ {
+ return ReadRawVarint64();
+ }
+
+ /// <summary>
+ /// Reads an int64 field from the stream.
+ /// </summary>
+ public long ReadInt64()
+ {
+ return (long) ReadRawVarint64();
+ }
+
+ /// <summary>
+ /// Reads an int32 field from the stream.
+ /// </summary>
+ public int ReadInt32()
+ {
+ 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);
+ }
+
+ /// <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
+ }
+}
\ No newline at end of file