Protocol Buffers - Google's data interchange format (grpc依赖) https://developers.google.com/protocol-buffers/
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// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.
// http://code.google.com/p/protobuf/
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
using System;
using System.IO;
using System.Text;
using Google.ProtocolBuffers.Descriptors;
namespace Google.ProtocolBuffers {
/// <summary>
/// Encodes and writes protocol message fields.
/// </summary>
/// <remarks>
/// This class contains two kinds of methods: methods that write specific
/// protocol message constructs and field types (e.g. WriteTag and
/// WriteInt32) and methods that write low-level values (e.g.
/// WriteRawVarint32 and WriteRawBytes). If you are writing encoded protocol
/// messages, you should use the former methods, but if you are writing some
/// other format of your own design, use the latter. The names of the former
/// methods are taken from the protocol buffer type names, not .NET types.
/// (Hence WriteFloat instead of WriteSingle, and WriteBool instead of WriteBoolean.)
/// </remarks>
public sealed class CodedOutputStream {
/// <summary>
/// The buffer size used by CreateInstance(Stream).
/// </summary>
public static readonly int DefaultBufferSize = 4096;
private readonly byte[] buffer;
private readonly int limit;
private int position;
private readonly Stream output;
#region Construction
private CodedOutputStream(byte[] buffer, int offset, int length) {
this.output = null;
this.buffer = buffer;
this.position = offset;
this.limit = offset + length;
}
private CodedOutputStream(Stream output, byte[] buffer) {
this.output = output;
this.buffer = buffer;
this.position = 0;
this.limit = buffer.Length;
}
/// <summary>
/// Creates a new CodedOutputStream which write to the given stream.
/// </summary>
public static CodedOutputStream CreateInstance(Stream output) {
return CreateInstance(output, DefaultBufferSize);
}
/// <summary>
/// Creates a new CodedOutputStream which write to the given stream and uses
/// the specified buffer size.
/// </summary>
public static CodedOutputStream CreateInstance(Stream output, int bufferSize) {
return new CodedOutputStream(output, new byte[bufferSize]);
}
/// <summary>
/// Creates a new CodedOutputStream that writes directly to the given
/// byte array. If more bytes are written than fit in the array,
/// OutOfSpaceException will be thrown.
/// </summary>
public static CodedOutputStream CreateInstance(byte[] flatArray) {
return CreateInstance(flatArray, 0, flatArray.Length);
}
/// <summary>
/// Creates a new CodedOutputStream that writes directly to the given
/// byte array slice. If more bytes are written than fit in the array,
/// OutOfSpaceException will be thrown.
/// </summary>
public static CodedOutputStream CreateInstance(byte[] flatArray, int offset, int length) {
return new CodedOutputStream(flatArray, offset, length);
}
#endregion
#region Writing of tags etc
/// <summary>
/// Writes a double field value, including tag, to the stream.
/// </summary>
public void WriteDouble(int fieldNumber, double value) {
WriteTag(fieldNumber, WireFormat.WireType.Fixed64);
WriteRawLittleEndian64(BitConverter.DoubleToInt64Bits(value));
}
/// <summary>
/// Writes a float field value, including tag, to the stream.
/// </summary>
public void WriteFloat(int fieldNumber, float value) {
WriteTag(fieldNumber, WireFormat.WireType.Fixed32);
// FIXME: How do we convert a single to 32 bits? (Without unsafe code)
//WriteRawLittleEndian32(BitConverter.SingleT(value));
}
/// <summary>
/// Writes a uint64 field value, including tag, to the stream.
/// </summary>
public void WriteUInt64(int fieldNumber, ulong value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawVarint64(value);
}
/// <summary>
/// Writes an int64 field value, including tag, to the stream.
/// </summary>
public void WriteInt64(int fieldNumber, long value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawVarint64((ulong)value);
}
/// <summary>
/// Writes an int32 field value, including tag, to the stream.
/// </summary>
public void WriteInt32(int fieldNumber, int value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
if (value >= 0) {
WriteRawVarint32((uint)value);
} else {
// Must sign-extend.
WriteRawVarint64((ulong)value);
}
}
/// <summary>
/// Writes a fixed64 field value, including tag, to the stream.
/// </summary>
public void WriteFixed64(int fieldNumber, long value) {
WriteTag(fieldNumber, WireFormat.WireType.Fixed64);
WriteRawLittleEndian64(value);
}
/// <summary>
/// Writes a fixed32 field value, including tag, to the stream.
/// </summary>
public void WriteFixed32(int fieldNumber, int value) {
WriteTag(fieldNumber, WireFormat.WireType.Fixed32);
WriteRawLittleEndian32(value);
}
/// <summary>
/// Writes a bool field value, including tag, to the stream.
/// </summary>
public void WriteBool(int fieldNumber, bool value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawByte(value ? (byte)1 : (byte)0);
}
/// <summary>
/// Writes a string field value, including tag, to the stream.
/// </summary>
public void WriteString(int fieldNumber, string value) {
WriteTag(fieldNumber, WireFormat.WireType.LengthDelimited);
// TODO(jonskeet): Optimise this if possible
// Unfortunately there does not appear to be any way to tell Java to encode
// UTF-8 directly into our buffer, so we have to let it create its own byte
// array and then copy. In .NET we can do the same thing very easily,
// so we don't need to worry about only writing one buffer at a time.
// We can optimise later.
byte[] bytes = Encoding.UTF8.GetBytes(value);
WriteRawVarint32((uint)bytes.Length);
WriteRawBytes(bytes);
}
/// <summary>
/// Writes a group field value, including tag, to the stream.
/// </summary>
public void WriteGroup(int fieldNumber, IMessage value) {
WriteTag(fieldNumber, WireFormat.WireType.StartGroup);
value.WriteTo(this);
WriteTag(fieldNumber, WireFormat.WireType.EndGroup);
}
public void WriteUnknownGroup(int fieldNumber, UnknownFieldSet value) {
WriteTag(fieldNumber, WireFormat.WireType.StartGroup);
value.WriteTo(this);
WriteTag(fieldNumber, WireFormat.WireType.EndGroup);
}
public void WriteMessage(int fieldNumber, IMessage value) {
WriteTag(fieldNumber, WireFormat.WireType.LengthDelimited);
WriteRawVarint32((uint)value.SerializedSize);
value.WriteTo(this);
}
public void WriteBytes(int fieldNumber, ByteString value) {
// TODO(jonskeet): Optimise this! (No need to copy the bytes twice.)
byte[] bytes = value.ToByteArray();
WriteRawVarint32((uint)bytes.Length);
WriteRawBytes(bytes);
}
public void WriteUInt32(int fieldNumber, uint value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawVarint32(value);
}
public void WriteEnum(int fieldNumber, int value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawVarint32((uint)value);
}
public void WriteSFixed32(int fieldNumber, int value) {
WriteTag(fieldNumber, WireFormat.WireType.Fixed32);
WriteRawVarint32((uint)value);
}
public void WriteSFixed64(int fieldNumber, long value) {
WriteTag(fieldNumber, WireFormat.WireType.Fixed64);
WriteRawVarint64((ulong)value);
}
public void WriteSInt32(int fieldNumber, int value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawVarint32(EncodeZigZag32(value));
}
public void WriteSInt64(int fieldNumber, long value) {
WriteTag(fieldNumber, WireFormat.WireType.Varint);
WriteRawVarint64(EncodeZigZag64(value));
}
public void WriteMessageSetExtension(int fieldNumber, IMessage value) {
WriteTag(WireFormat.MessageSetField.Item, WireFormat.WireType.StartGroup);
WriteUInt32(WireFormat.MessageSetField.TypeID, (uint)fieldNumber);
WriteMessage(WireFormat.MessageSetField.Message, value);
WriteTag(WireFormat.MessageSetField.Item, WireFormat.WireType.EndGroup);
}
public void WriteRawMessageSetExtension(int fieldNumber, ByteString value) {
WriteTag(WireFormat.MessageSetField.Item, WireFormat.WireType.StartGroup);
WriteUInt32(WireFormat.MessageSetField.TypeID, (uint)fieldNumber);
WriteBytes(WireFormat.MessageSetField.Message, value);
WriteTag(WireFormat.MessageSetField.Item, WireFormat.WireType.EndGroup);
}
public void WriteField(FieldType fieldType, int fieldNumber, object value) {
switch (fieldType) {
case FieldType.Double: WriteDouble(fieldNumber, (double)value); break;
case FieldType.Float: WriteFloat(fieldNumber, (float)value); break;
case FieldType.Int64: WriteInt64(fieldNumber, (long)value); break;
case FieldType.UInt64: WriteUInt64(fieldNumber, (ulong)value); break;
case FieldType.Int32: WriteInt32(fieldNumber, (int)value); break;
case FieldType.Fixed64: WriteFixed64(fieldNumber, (long)value); break;
case FieldType.Fixed32: WriteFixed32(fieldNumber, (int)value); break;
case FieldType.Bool: WriteBool(fieldNumber, (bool)value); break;
case FieldType.String: WriteString(fieldNumber, (string)value); break;
case FieldType.Group: WriteGroup(fieldNumber, (IMessage)value); break;
case FieldType.Message: WriteMessage(fieldNumber, (IMessage)value); break;
case FieldType.Bytes: WriteBytes(fieldNumber, (ByteString)value); break;
case FieldType.UInt32: WriteUInt32(fieldNumber, (uint)value); break;
case FieldType.SFixed32: WriteSFixed32(fieldNumber, (int)value); break;
case FieldType.SFixed64: WriteSFixed64(fieldNumber, (long)value); break;
case FieldType.SInt32: WriteSInt32(fieldNumber, (int)value); break;
case FieldType.SInt64: WriteSInt64(fieldNumber, (long)value); break;
case FieldType.Enum: WriteEnum(fieldNumber, ((EnumValueDescriptor)value).Number);
break;
}
}
#endregion
#region Underlying writing primitives
/// <summary>
/// Encodes and writes a tag.
/// </summary>
public void WriteTag(int fieldNumber, WireFormat.WireType type) {
WriteRawVarint32(WireFormat.MakeTag(fieldNumber, type));
}
public void WriteRawVarint32(uint value) {
while (true) {
if ((value & ~0x7F) == 0) {
WriteRawByte(value);
return;
} else {
WriteRawByte((value & 0x7F) | 0x80);
value >>= 7;
}
}
}
public void WriteRawVarint64(ulong value) {
while (true) {
if ((value & ~0x7FUL) == 0) {
WriteRawByte((uint)value);
return;
} else {
WriteRawByte(((uint)value & 0x7F) | 0x80);
value >>= 7;
}
}
}
public void WriteRawLittleEndian32(int value) {
WriteRawByte((byte)value);
WriteRawByte((byte)(value >> 8));
WriteRawByte((byte)(value >> 16));
WriteRawByte((byte)(value >> 24));
}
public void WriteRawLittleEndian64(long value) {
WriteRawByte((byte)value);
WriteRawByte((byte)(value >> 8));
WriteRawByte((byte)(value >> 16));
WriteRawByte((byte)(value >> 24));
WriteRawByte((byte)(value >> 32));
WriteRawByte((byte)(value >> 40));
WriteRawByte((byte)(value >> 48));
WriteRawByte((byte)(value >> 56));
}
public void WriteRawByte(byte value) {
if (position == limit) {
RefreshBuffer();
}
buffer[position++] = value;
}
public void WriteRawByte(uint value) {
WriteRawByte((byte)value);
}
/// <summary>
/// Writes out an array of bytes.
/// </summary>
public void WriteRawBytes(byte[] value) {
WriteRawBytes(value, 0, value.Length);
}
/// <summary>
/// Writes out part of an array of bytes.
/// </summary>
public void WriteRawBytes(byte[] value, int offset, int length) {
if (limit - position >= length) {
Array.Copy(value, offset, buffer, position, length);
// We have room in the current buffer.
position += length;
} else {
// Write extends past current buffer. Fill the rest of this buffer and
// flush.
int bytesWritten = limit - position;
Array.Copy(value, offset, buffer, position, bytesWritten);
offset += bytesWritten;
length -= bytesWritten;
position = limit;
RefreshBuffer();
// Now deal with the rest.
// Since we have an output stream, this is our buffer
// and buffer offset == 0
if (length <= limit) {
// Fits in new buffer.
Array.Copy(value, offset, buffer, 0, length);
position = length;
} else {
// Write is very big. Let's do it all at once.
output.Write(value, offset, length);
}
}
}
#endregion
#region Size computations
const int LittleEndian64Size = 8;
const int LittleEndian32Size = 4;
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// double field, including the tag.
/// </summary>
public static int ComputeDoubleSize(int fieldNumber, double value) {
return ComputeTagSize(fieldNumber) + LittleEndian64Size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// float field, including the tag.
/// </summary>
public static int ComputeFloatSize(int fieldNumber, float value) {
return ComputeTagSize(fieldNumber) + LittleEndian32Size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// uint64 field, including the tag.
/// </summary>
public static int ComputeUInt64Size(int fieldNumber, ulong value) {
return ComputeTagSize(fieldNumber) + ComputeRawVarint64Size(value);
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// int64 field, including the tag.
/// </summary>
public static int ComputeInt64Size(int fieldNumber, long value) {
return ComputeTagSize(fieldNumber) + ComputeRawVarint64Size((ulong)value);
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// int32 field, including the tag.
/// </summary>
public static int ComputeInt32Size(int fieldNumber, int value) {
if (value >= 0) {
return ComputeTagSize(fieldNumber) + ComputeRawVarint32Size((uint)value);
} else {
// Must sign-extend.
return ComputeTagSize(fieldNumber) + 10;
}
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// fixed64 field, including the tag.
/// </summary>
public static int ComputeFixed64Size(int fieldNumber, long value) {
return ComputeTagSize(fieldNumber) + LittleEndian64Size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// fixed32 field, including the tag.
/// </summary>
public static int ComputeFixed32Size(int fieldNumber, int value) {
return ComputeTagSize(fieldNumber) + LittleEndian32Size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// bool field, including the tag.
/// </summary>
public static int ComputeBoolSize(int fieldNumber, bool value) {
return ComputeTagSize(fieldNumber) + 1;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// string field, including the tag.
/// </summary>
public static int ComputeStringSize(int fieldNumber, String value) {
int byteArraySize = Encoding.UTF8.GetByteCount(value);
return ComputeTagSize(fieldNumber) +
ComputeRawVarint32Size((uint)byteArraySize) +
byteArraySize;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// group field, including the tag.
/// </summary>
public static int ComputeGroupSize(int fieldNumber, IMessage value) {
return ComputeTagSize(fieldNumber) * 2 + value.SerializedSize;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// group field represented by an UnknownFieldSet, including the tag.
/// </summary>
public static int ComputeUnknownGroupSize(int fieldNumber,
UnknownFieldSet value) {
return ComputeTagSize(fieldNumber) * 2 + value.SerializedSize;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// embedded message field, including the tag.
/// </summary>
public static int ComputeMessageSize(int fieldNumber, IMessage value) {
int size = value.SerializedSize;
return ComputeTagSize(fieldNumber) + ComputeRawVarint32Size((uint)size) + size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// bytes field, including the tag.
/// </summary>
public static int ComputeBytesSize(int fieldNumber, ByteString value) {
return ComputeTagSize(fieldNumber) +
ComputeRawVarint32Size((uint)value.Length) +
value.Length;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// uint32 field, including the tag.
/// </summary>
public static int ComputeUInt32Size(int fieldNumber, uint value) {
return ComputeTagSize(fieldNumber) + ComputeRawVarint32Size(value);
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// enum field, including the tag. The caller is responsible for
/// converting the enum value to its numeric value.
/// </summary>
public static int ComputeEnumSize(int fieldNumber, int value) {
return ComputeTagSize(fieldNumber) + ComputeRawVarint32Size((uint)value);
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// sfixed32 field, including the tag.
/// </summary>
public static int ComputeSFixed32Size(int fieldNumber, int value) {
return ComputeTagSize(fieldNumber) + LittleEndian32Size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// sfixed64 field, including the tag.
/// </summary>
public static int ComputeSFixed64Size(int fieldNumber, long value) {
return ComputeTagSize(fieldNumber) + LittleEndian64Size;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// sint32 field, including the tag.
/// </summary>
public static int ComputeSInt32Size(int fieldNumber, int value) {
return ComputeTagSize(fieldNumber) +
ComputeRawVarint32Size(EncodeZigZag32(value));
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// sint64 field, including the tag.
/// </summary>
public static int ComputeSInt64Size(int fieldNumber, long value) {
return ComputeTagSize(fieldNumber) +
ComputeRawVarint64Size(EncodeZigZag64(value));
}
/*
* Compute the number of bytes that would be needed to encode a
* MessageSet extension to the stream. For historical reasons,
* the wire format differs from normal fields.
*/
/// <summary>
/// Compute the number of bytes that would be needed to encode a
/// MessageSet extension to the stream. For historical reasons,
/// the wire format differs from normal fields.
/// </summary>
public static int ComputeMessageSetExtensionSize(int fieldNumber, IMessage value) {
return ComputeTagSize(WireFormat.MessageSetField.Item) * 2 +
ComputeUInt32Size(WireFormat.MessageSetField.TypeID, (uint) fieldNumber) +
ComputeMessageSize(WireFormat.MessageSetField.Message, value);
}
/// <summary>
/// Compute the number of bytes that would be needed to encode an
/// unparsed MessageSet extension field to the stream. For
/// historical reasons, the wire format differs from normal fields.
/// </summary>
public static int ComputeRawMessageSetExtensionSize(int fieldNumber, ByteString value) {
return ComputeTagSize(WireFormat.MessageSetField.Item) * 2 +
ComputeUInt32Size(WireFormat.MessageSetField.TypeID, (uint) fieldNumber) +
ComputeBytesSize(WireFormat.MessageSetField.Message, value);
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a varint.
/// </summary>
public static int ComputeRawVarint32Size(uint value) {
if ((value & (0xffffffff << 7)) == 0) return 1;
if ((value & (0xffffffff << 14)) == 0) return 2;
if ((value & (0xffffffff << 21)) == 0) return 3;
if ((value & (0xffffffff << 28)) == 0) return 4;
return 5;
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a varint.
/// </summary>
public static int ComputeRawVarint64Size(ulong value) {
if ((value & (0xffffffffffffffffL << 7)) == 0) return 1;
if ((value & (0xffffffffffffffffL << 14)) == 0) return 2;
if ((value & (0xffffffffffffffffL << 21)) == 0) return 3;
if ((value & (0xffffffffffffffffL << 28)) == 0) return 4;
if ((value & (0xffffffffffffffffL << 35)) == 0) return 5;
if ((value & (0xffffffffffffffffL << 42)) == 0) return 6;
if ((value & (0xffffffffffffffffL << 49)) == 0) return 7;
if ((value & (0xffffffffffffffffL << 56)) == 0) return 8;
if ((value & (0xffffffffffffffffL << 63)) == 0) return 9;
return 10;
}
/*
* Compute the number of bytes that would be needed to encode a
* field of arbitrary type, including tag, to the stream.
*
* @param type The field's type.
* @param number The field's number.
* @param value Object representing the field's value. Must be of the exact
* type which would be returned by
* {@link Message#getField(FieldDescriptor)} for
* this field.
*/
public static int ComputeFieldSize(FieldType fieldType, int fieldNumber, Object value) {
switch (fieldType) {
case FieldType.Double: return ComputeDoubleSize(fieldNumber, (double)value);
case FieldType.Float: return ComputeFloatSize(fieldNumber, (float)value);
case FieldType.Int64: return ComputeInt64Size(fieldNumber, (long)value);
case FieldType.UInt64: return ComputeUInt64Size(fieldNumber, (ulong)value);
case FieldType.Int32: return ComputeInt32Size(fieldNumber, (int)value);
case FieldType.Fixed64: return ComputeFixed64Size(fieldNumber, (long)value);
case FieldType.Fixed32: return ComputeFixed32Size(fieldNumber, (int)value);
case FieldType.Bool: return ComputeBoolSize(fieldNumber, (bool)value);
case FieldType.String: return ComputeStringSize(fieldNumber, (string)value);
case FieldType.Group: return ComputeGroupSize(fieldNumber, (IMessage)value);
case FieldType.Message: return ComputeMessageSize(fieldNumber, (IMessage)value);
case FieldType.Bytes: return ComputeBytesSize(fieldNumber, (ByteString)value);
case FieldType.UInt32: return ComputeUInt32Size(fieldNumber, (uint)value);
case FieldType.SFixed32: return ComputeSFixed32Size(fieldNumber, (int)value);
case FieldType.SFixed64: return ComputeSFixed64Size(fieldNumber, (long)value);
case FieldType.SInt32: return ComputeSInt32Size(fieldNumber, (int)value);
case FieldType.SInt64: return ComputeSInt64Size(fieldNumber, (long)value);
case FieldType.Enum: return ComputeEnumSize(fieldNumber, ((EnumValueDescriptor)value).Number);
default:
throw new ArgumentOutOfRangeException("Invalid field type " + fieldType);
}
}
/// <summary>
/// Compute the number of bytes that would be needed to encode a tag.
/// </summary>
public static int ComputeTagSize(int fieldNumber) {
return ComputeRawVarint32Size(WireFormat.MakeTag(fieldNumber, 0));
}
#endregion
/// <summary>
/// Encode 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>
public static uint EncodeZigZag32(int n) {
// Note: the right-shift must be arithmetic
return (uint)((n << 1) ^ (n >> 31));
}
/// <summary>
/// Encode a 64-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>
public static ulong EncodeZigZag64(long n) {
return (ulong)((n << 1) ^ (n >> 63));
}
private void RefreshBuffer() {
if (output == null) {
// We're writing to a single buffer.
throw new OutOfSpaceException();
}
// Since we have an output stream, this is our buffer
// and buffer offset == 0
output.Write(buffer, 0, position);
position = 0;
}
/// <summary>
/// Indicates that a CodedOutputStream wrapping a flat byte array
/// ran out of space.
/// </summary>
public class OutOfSpaceException : IOException {
internal OutOfSpaceException()
: base("CodedOutputStream was writing to a flat byte array and ran out of space.") {
}
}
public void Flush() {
if (output != null) {
RefreshBuffer();
}
}
/// <summary>
/// Verifies that SpaceLeft returns zero. It's common to create a byte array
/// that is exactly big enough to hold a message, then write to it with
/// a CodedOutputStream. Calling CheckNoSpaceLeft after writing verifies that
/// the message was actually as big as expected, which can help bugs.
/// </summary>
public void CheckNoSpaceLeft() {
if (SpaceLeft != 0) {
throw new InvalidOperationException("Did not write as much data as expected.");
}
}
/// <summary>
/// If writing to a flat array, returns the space left in the array. Otherwise,
/// throws an InvalidOperationException.
/// </summary>
public int SpaceLeft {
get {
if (output == null) {
return limit - position;
} else {
throw new InvalidOperationException(
"SpaceLeft can only be called on CodedOutputStreams that are " +
"writing to a flat array.");
}
}
}
}
}