ClickHouse/src/Formats/ProtobufReader.h
Robert Schulze 09c62f6728
Consolidate config_formats.h into config.h
Less duplication, less confusion ...
2022-09-28 12:59:05 +00:00

72 lines
1.7 KiB
C++

#pragma once
#include "config.h"
#if USE_PROTOBUF
# include <Common/PODArray.h>
# include <IO/ReadBuffer.h>
namespace DB
{
class ReadBuffer;
/// Utility class for reading in the Protobuf format.
/// Knows nothing about protobuf schemas, just provides useful functions to serialize data.
class ProtobufReader
{
public:
explicit ProtobufReader(ReadBuffer & in_);
void startMessage(bool with_length_delimiter_);
void endMessage(bool ignore_errors);
void startNestedMessage();
void endNestedMessage();
bool readFieldNumber(int & field_number);
Int64 readInt();
Int64 readSInt();
UInt64 readUInt();
template<typename T> T readFixed();
void readString(String & str);
void readStringAndAppend(PaddedPODArray<UInt8> & str);
bool eof() const { return in.eof(); }
private:
void readBinary(void * data, size_t size);
void ignore(UInt64 num_bytes);
void ignoreAll();
void moveCursorBackward(UInt64 num_bytes);
UInt64 ALWAYS_INLINE readVarint()
{
char c;
in.readStrict(c);
UInt64 first_byte = static_cast<UInt8>(c);
++cursor;
if (likely(!(c & 0x80)))
return first_byte;
return continueReadingVarint(first_byte);
}
UInt64 continueReadingVarint(UInt64 first_byte);
void ignoreVarint();
void ignoreGroup();
[[noreturn]] void throwUnknownFormat() const;
ReadBuffer & in;
Int64 cursor = 0;
bool root_message_has_length_delimiter = false;
size_t current_message_level = 0;
Int64 current_message_end = 0;
std::vector<Int64> parent_message_ends;
int field_number = 0;
int next_field_number = 0;
Int64 field_end = 0;
};
}
#endif