ClickHouse/src/Common/hex.h
2020-04-03 18:14:31 +03:00

113 lines
2.7 KiB
C++

#pragma once
#include <string>
/// Maps 0..15 to 0..9A..F or 0..9a..f correspondingly.
extern const char * const hex_digit_to_char_uppercase_table;
extern const char * const hex_digit_to_char_lowercase_table;
inline char hexDigitUppercase(unsigned char c)
{
return hex_digit_to_char_uppercase_table[c];
}
inline char hexDigitLowercase(unsigned char c)
{
return hex_digit_to_char_lowercase_table[c];
}
#include <cstring>
#include <cstddef>
#include <common/types.h>
/// Maps 0..255 to 00..FF or 00..ff correspondingly
extern const char * const hex_byte_to_char_uppercase_table;
extern const char * const hex_byte_to_char_lowercase_table;
inline void writeHexByteUppercase(UInt8 byte, void * out)
{
memcpy(out, &hex_byte_to_char_uppercase_table[static_cast<size_t>(byte) * 2], 2);
}
inline void writeHexByteLowercase(UInt8 byte, void * out)
{
memcpy(out, &hex_byte_to_char_lowercase_table[static_cast<size_t>(byte) * 2], 2);
}
/// Produces hex representation of an unsigned int with leading zeros (for checksums)
template <typename TUInt>
inline void writeHexUIntImpl(TUInt uint_, char * out, const char * const table)
{
union
{
TUInt value;
UInt8 uint8[sizeof(TUInt)];
};
value = uint_;
/// Use little endian
for (size_t i = 0; i < sizeof(TUInt); ++i)
memcpy(out + i * 2, &table[static_cast<size_t>(uint8[sizeof(TUInt) - 1 - i]) * 2], 2);
}
template <typename TUInt>
inline void writeHexUIntUppercase(TUInt uint_, char * out)
{
writeHexUIntImpl(uint_, out, hex_byte_to_char_uppercase_table);
}
template <typename TUInt>
inline void writeHexUIntLowercase(TUInt uint_, char * out)
{
writeHexUIntImpl(uint_, out, hex_byte_to_char_lowercase_table);
}
template <typename TUInt>
std::string getHexUIntUppercase(TUInt uint_)
{
std::string res(sizeof(TUInt) * 2, '\0');
writeHexUIntUppercase(uint_, res.data());
return res;
}
template <typename TUInt>
std::string getHexUIntLowercase(TUInt uint_)
{
std::string res(sizeof(TUInt) * 2, '\0');
writeHexUIntLowercase(uint_, res.data());
return res;
}
/// Maps 0..9, A..F, a..f to 0..15. Other chars are mapped to implementation specific value.
extern const char * const hex_char_to_digit_table;
inline char unhex(char c)
{
return hex_char_to_digit_table[static_cast<UInt8>(c)];
}
inline char unhex2(const char * data)
{
return
static_cast<UInt8>(unhex(data[0])) * 0x10
+ static_cast<UInt8>(unhex(data[1]));
}
inline UInt16 unhex4(const char * data)
{
return
static_cast<UInt16>(unhex(data[0])) * 0x1000
+ static_cast<UInt16>(unhex(data[1])) * 0x100
+ static_cast<UInt16>(unhex(data[2])) * 0x10
+ static_cast<UInt16>(unhex(data[3]));
}