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ClickHouse/src/IO/ReadHelpers.h
Alexey Milovidov c2faf450d1 Fix error
2021-10-17 06:37:51 +03:00

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#pragma once
#include <cmath>
#include <cstring>
#include <limits>
#include <algorithm>
#include <iterator>
#include <type_traits>
#include <base/DateLUT.h>
#include <base/LocalDate.h>
#include <base/LocalDateTime.h>
#include <base/StringRef.h>
#include <base/arithmeticOverflow.h>
#include <base/unit.h>
#include <Core/Types.h>
#include <Core/DecimalFunctions.h>
#include <Core/UUID.h>
#include <Common/Allocator.h>
#include <Common/Exception.h>
#include <Common/StringUtils/StringUtils.h>
#include <Common/Arena.h>
#include <Common/intExp.h>
#include <Formats/FormatSettings.h>
#include <IO/CompressionMethod.h>
#include <IO/ReadBuffer.h>
#include <IO/ReadBufferFromMemory.h>
#include <IO/VarInt.h>
#include <DataTypes/DataTypeDateTime.h>
#include <double-conversion/double-conversion.h>
static constexpr auto DEFAULT_MAX_STRING_SIZE = 1_GiB;
namespace DB
{
template <typename Allocator>
struct Memory;
namespace ErrorCodes
{
extern const int CANNOT_PARSE_DATE;
extern const int CANNOT_PARSE_DATETIME;
extern const int CANNOT_PARSE_UUID;
extern const int CANNOT_READ_ARRAY_FROM_TEXT;
extern const int CANNOT_PARSE_NUMBER;
extern const int INCORRECT_DATA;
}
/// Helper functions for formatted input.
inline char parseEscapeSequence(char c)
{
switch (c)
{
case 'a':
return '\a';
case 'b':
return '\b';
case 'e':
return '\x1B'; /// \e escape sequence is non standard for C and C++ but supported by gcc and clang.
case 'f':
return '\f';
case 'n':
return '\n';
case 'r':
return '\r';
case 't':
return '\t';
case 'v':
return '\v';
case '0':
return '\0';
default:
return c;
}
}
/// These functions are located in VarInt.h
/// inline void throwReadAfterEOF()
inline void readChar(char & x, ReadBuffer & buf)
{
if (!buf.eof())
{
x = *buf.position();
++buf.position();
}
else
throwReadAfterEOF();
}
/// Read POD-type in native format
template <typename T>
inline void readPODBinary(T & x, ReadBuffer & buf)
{
buf.readStrict(reinterpret_cast<char *>(&x), sizeof(x));
}
template <typename T>
inline void readIntBinary(T & x, ReadBuffer & buf)
{
readPODBinary(x, buf);
}
template <typename T>
inline void readFloatBinary(T & x, ReadBuffer & buf)
{
readPODBinary(x, buf);
}
inline void readStringBinary(std::string & s, ReadBuffer & buf, size_t MAX_STRING_SIZE = DEFAULT_MAX_STRING_SIZE)
{
size_t size = 0;
readVarUInt(size, buf);
if (size > MAX_STRING_SIZE)
throw Poco::Exception("Too large string size.");
s.resize(size);
buf.readStrict(s.data(), size);
}
inline StringRef readStringBinaryInto(Arena & arena, ReadBuffer & buf)
{
size_t size = 0;
readVarUInt(size, buf);
char * data = arena.alloc(size);
buf.readStrict(data, size);
return StringRef(data, size);
}
template <typename T>
void readVectorBinary(std::vector<T> & v, ReadBuffer & buf, size_t MAX_VECTOR_SIZE = DEFAULT_MAX_STRING_SIZE)
{
size_t size = 0;
readVarUInt(size, buf);
if (size > MAX_VECTOR_SIZE)
throw Poco::Exception("Too large vector size.");
v.resize(size);
for (size_t i = 0; i < size; ++i)
readBinary(v[i], buf);
}
void assertString(const char * s, ReadBuffer & buf);
void assertEOF(ReadBuffer & buf);
[[noreturn]] void throwAtAssertionFailed(const char * s, ReadBuffer & buf);
inline bool checkChar(char c, ReadBuffer & buf) // -V1071
{
char a;
if (!buf.peek(a) || a != c)
return false;
buf.ignore();
return true;
}
inline void assertChar(char symbol, ReadBuffer & buf)
{
if (!checkChar(symbol, buf))
{
char err[2] = {symbol, '\0'};
throwAtAssertionFailed(err, buf);
}
}
inline void assertString(const String & s, ReadBuffer & buf)
{
assertString(s.c_str(), buf);
}
bool checkString(const char * s, ReadBuffer & buf);
inline bool checkString(const String & s, ReadBuffer & buf)
{
return checkString(s.c_str(), buf);
}
bool checkStringCaseInsensitive(const char * s, ReadBuffer & buf);
inline bool checkStringCaseInsensitive(const String & s, ReadBuffer & buf)
{
return checkStringCaseInsensitive(s.c_str(), buf);
}
void assertStringCaseInsensitive(const char * s, ReadBuffer & buf);
inline void assertStringCaseInsensitive(const String & s, ReadBuffer & buf)
{
return assertStringCaseInsensitive(s.c_str(), buf);
}
/** Check that next character in buf matches first character of s.
* If true, then check all characters in s and throw exception if it doesn't match.
* If false, then return false, and leave position in buffer unchanged.
*/
bool checkStringByFirstCharacterAndAssertTheRest(const char * s, ReadBuffer & buf);
bool checkStringByFirstCharacterAndAssertTheRestCaseInsensitive(const char * s, ReadBuffer & buf);
inline bool checkStringByFirstCharacterAndAssertTheRest(const String & s, ReadBuffer & buf)
{
return checkStringByFirstCharacterAndAssertTheRest(s.c_str(), buf);
}
inline bool checkStringByFirstCharacterAndAssertTheRestCaseInsensitive(const String & s, ReadBuffer & buf)
{
return checkStringByFirstCharacterAndAssertTheRestCaseInsensitive(s.c_str(), buf);
}
inline void readBoolText(bool & x, ReadBuffer & buf)
{
char tmp = '0';
readChar(tmp, buf);
x = tmp != '0';
}
inline void readBoolTextWord(bool & x, ReadBuffer & buf)
{
if (buf.eof())
throwReadAfterEOF();
if (*buf.position() == 't')
{
assertString("true", buf);
x = true;
}
else
{
assertString("false", buf);
x = false;
}
}
enum class ReadIntTextCheckOverflow
{
DO_NOT_CHECK_OVERFLOW,
CHECK_OVERFLOW,
};
template <typename T, typename ReturnType = void, ReadIntTextCheckOverflow check_overflow = ReadIntTextCheckOverflow::DO_NOT_CHECK_OVERFLOW>
ReturnType readIntTextImpl(T & x, ReadBuffer & buf)
{
using UnsignedT = make_unsigned_t<T>;
static constexpr bool throw_exception = std::is_same_v<ReturnType, void>;
bool negative = false;
UnsignedT res{};
if (buf.eof())
{
if constexpr (throw_exception)
throwReadAfterEOF();
else
return ReturnType(false);
}
const size_t initial_pos = buf.count();
bool has_sign = false;
bool has_number = false;
while (!buf.eof())
{
switch (*buf.position())
{
case '+':
{
/// 123+ or +123+, just stop after 123 or +123.
if (has_number)
goto end;
/// No digits read yet, but we already read sign, like ++, -+.
if (has_sign)
{
if constexpr (throw_exception)
throw ParsingException(
"Cannot parse number with multiple sign (+/-) characters",
ErrorCodes::CANNOT_PARSE_NUMBER);
else
return ReturnType(false);
}
has_sign = true;
break;
}
case '-':
{
if (has_number)
goto end;
if (has_sign)
{
if constexpr (throw_exception)
throw ParsingException(
"Cannot parse number with multiple sign (+/-) characters",
ErrorCodes::CANNOT_PARSE_NUMBER);
else
return ReturnType(false);
}
if constexpr (is_signed_v<T>)
negative = true;
else
{
if constexpr (throw_exception)
throw ParsingException("Unsigned type must not contain '-' symbol", ErrorCodes::CANNOT_PARSE_NUMBER);
else
return ReturnType(false);
}
has_sign = true;
break;
}
case '0': [[fallthrough]];
case '1': [[fallthrough]];
case '2': [[fallthrough]];
case '3': [[fallthrough]];
case '4': [[fallthrough]];
case '5': [[fallthrough]];
case '6': [[fallthrough]];
case '7': [[fallthrough]];
case '8': [[fallthrough]];
case '9':
{
has_number = true;
if constexpr (check_overflow == ReadIntTextCheckOverflow::CHECK_OVERFLOW && !is_big_int_v<T>)
{
/// Perform relativelly slow overflow check only when
/// number of decimal digits so far is close to the max for given type.
/// Example: 20 * 10 will overflow Int8.
if (buf.count() - initial_pos + 1 >= std::numeric_limits<T>::max_digits10)
{
if (negative)
{
T signed_res = -res;
if (common::mulOverflow<T>(signed_res, 10, signed_res) ||
common::subOverflow<T>(signed_res, (*buf.position() - '0'), signed_res))
return ReturnType(false);
res = -static_cast<UnsignedT>(signed_res);
}
else
{
T signed_res = res;
if (common::mulOverflow<T>(signed_res, 10, signed_res) ||
common::addOverflow<T>(signed_res, (*buf.position() - '0'), signed_res))
return ReturnType(false);
res = signed_res;
}
break;
}
}
res *= 10;
res += *buf.position() - '0';
break;
}
default:
goto end;
}
++buf.position();
}
end:
if (has_sign && !has_number)
{
if constexpr (throw_exception)
throw ParsingException(
"Cannot parse number with a sign character but without any numeric character", ErrorCodes::CANNOT_PARSE_NUMBER);
else
return ReturnType(false);
}
x = res;
if constexpr (is_signed_v<T>)
{
if (negative)
{
if constexpr (check_overflow == ReadIntTextCheckOverflow::CHECK_OVERFLOW)
{
if (common::mulOverflow<UnsignedT, Int8, T>(res, -1, x))
return ReturnType(false);
}
else
x = -res;
}
}
return ReturnType(true);
}
template <ReadIntTextCheckOverflow check_overflow = ReadIntTextCheckOverflow::DO_NOT_CHECK_OVERFLOW, typename T>
void readIntText(T & x, ReadBuffer & buf)
{
if constexpr (is_decimal<T>)
{
readIntText<check_overflow>(x.value, buf);
}
else
{
readIntTextImpl<T, void, check_overflow>(x, buf);
}
}
template <ReadIntTextCheckOverflow check_overflow = ReadIntTextCheckOverflow::CHECK_OVERFLOW, typename T>
bool tryReadIntText(T & x, ReadBuffer & buf) // -V1071
{
return readIntTextImpl<T, bool, check_overflow>(x, buf);
}
/** More efficient variant (about 1.5 times on real dataset).
* Differs in following:
* - for numbers starting with zero, parsed only zero;
* - symbol '+' before number is not supported;
*/
template <typename T, bool throw_on_error = true>
void readIntTextUnsafe(T & x, ReadBuffer & buf)
{
bool negative = false;
make_unsigned_t<T> res = 0;
auto on_error = []
{
if (throw_on_error)
throwReadAfterEOF();
};
if (unlikely(buf.eof()))
return on_error();
if (is_signed_v<T> && *buf.position() == '-')
{
++buf.position();
negative = true;
if (unlikely(buf.eof()))
return on_error();
}
if (*buf.position() == '0') /// There are many zeros in real datasets.
{
++buf.position();
x = 0;
return;
}
while (!buf.eof())
{
unsigned char value = *buf.position() - '0';
if (value < 10)
{
res *= 10;
res += value;
++buf.position();
}
else
break;
}
/// See note about undefined behaviour above.
x = is_signed_v<T> && negative ? -res : res;
}
template <typename T>
void tryReadIntTextUnsafe(T & x, ReadBuffer & buf)
{
return readIntTextUnsafe<T, false>(x, buf);
}
/// Look at readFloatText.h
template <typename T> void readFloatText(T & x, ReadBuffer & in);
template <typename T> bool tryReadFloatText(T & x, ReadBuffer & in);
/// simple: all until '\n' or '\t'
void readString(String & s, ReadBuffer & buf);
void readEscapedString(String & s, ReadBuffer & buf);
void readQuotedString(String & s, ReadBuffer & buf);
void readQuotedStringWithSQLStyle(String & s, ReadBuffer & buf);
void readDoubleQuotedString(String & s, ReadBuffer & buf);
void readDoubleQuotedStringWithSQLStyle(String & s, ReadBuffer & buf);
void readJSONString(String & s, ReadBuffer & buf);
void readBackQuotedString(String & s, ReadBuffer & buf);
void readBackQuotedStringWithSQLStyle(String & s, ReadBuffer & buf);
void readStringUntilEOF(String & s, ReadBuffer & buf);
// Reads the line until EOL, unescaping backslash escape sequences.
// Buffer pointer is left at EOL, don't forget to advance it.
void readEscapedStringUntilEOL(String & s, ReadBuffer & buf);
/// Only 0x20 as whitespace character
void readStringUntilWhitespace(String & s, ReadBuffer & buf);
/** Read string in CSV format.
* Parsing rules:
* - string could be placed in quotes; quotes could be single: ' if FormatSettings::CSV::allow_single_quotes is true
* or double: " if FormatSettings::CSV::allow_double_quotes is true;
* - or string could be unquoted - this is determined by first character;
* - if string is unquoted, then it is read until next delimiter,
* either until end of line (CR or LF),
* or until end of stream;
* but spaces and tabs at begin and end of unquoted string are consumed but ignored (note that this behaviour differs from RFC).
* - if string is in quotes, then it will be read until closing quote,
* but sequences of two consecutive quotes are parsed as single quote inside string;
*/
void readCSVString(String & s, ReadBuffer & buf, const FormatSettings::CSV & settings);
/// Read and append result to array of characters.
template <typename Vector>
void readStringInto(Vector & s, ReadBuffer & buf);
template <typename Vector>
void readNullTerminated(Vector & s, ReadBuffer & buf);
template <typename Vector>
void readEscapedStringInto(Vector & s, ReadBuffer & buf);
template <bool enable_sql_style_quoting, typename Vector>
void readQuotedStringInto(Vector & s, ReadBuffer & buf);
template <bool enable_sql_style_quoting, typename Vector>
void readDoubleQuotedStringInto(Vector & s, ReadBuffer & buf);
template <bool enable_sql_style_quoting, typename Vector>
void readBackQuotedStringInto(Vector & s, ReadBuffer & buf);
template <typename Vector>
void readStringUntilEOFInto(Vector & s, ReadBuffer & buf);
template <typename Vector>
void readCSVStringInto(Vector & s, ReadBuffer & buf, const FormatSettings::CSV & settings);
/// ReturnType is either bool or void. If bool, the function will return false instead of throwing an exception.
template <typename Vector, typename ReturnType = void>
ReturnType readJSONStringInto(Vector & s, ReadBuffer & buf);
template <typename Vector>
bool tryReadJSONStringInto(Vector & s, ReadBuffer & buf)
{
return readJSONStringInto<Vector, bool>(s, buf);
}
template <typename Vector>
void readStringUntilWhitespaceInto(Vector & s, ReadBuffer & buf);
/// This could be used as template parameter for functions above, if you want to just skip data.
struct NullOutput
{
void append(const char *, size_t) {}
void push_back(char) {}
};
void parseUUID(const UInt8 * src36, UInt8 * dst16);
void parseUUIDWithoutSeparator(const UInt8 * src36, UInt8 * dst16);
void parseUUID(const UInt8 * src36, std::reverse_iterator<UInt8 *> dst16);
void parseUUIDWithoutSeparator(const UInt8 * src36, std::reverse_iterator<UInt8 *> dst16);
template <typename ReturnType>
ReturnType readDateTextFallback(LocalDate & date, ReadBuffer & buf);
/// In YYYY-MM-DD format.
/// For convenience, Month and Day parts can have single digit instead of two digits.
/// Any separators other than '-' are supported.
template <typename ReturnType = void>
inline ReturnType readDateTextImpl(LocalDate & date, ReadBuffer & buf)
{
/// Optimistic path, when whole value is in buffer.
if (!buf.eof() && buf.position() + 10 <= buf.buffer().end())
{
char * pos = buf.position();
/// YYYY-MM-DD
/// YYYY-MM-D
/// YYYY-M-DD
/// YYYY-M-D
/// The delimiters can be arbitrary characters, like YYYY/MM!DD, but obviously not digits.
UInt16 year = (pos[0] - '0') * 1000 + (pos[1] - '0') * 100 + (pos[2] - '0') * 10 + (pos[3] - '0');
pos += 5;
if (isNumericASCII(pos[-1]))
return ReturnType(false);
UInt8 month = pos[0] - '0';
if (isNumericASCII(pos[1]))
{
month = month * 10 + pos[1] - '0';
pos += 3;
}
else
pos += 2;
if (isNumericASCII(pos[-1]))
return ReturnType(false);
UInt8 day = pos[0] - '0';
if (isNumericASCII(pos[1]))
{
day = day * 10 + pos[1] - '0';
pos += 2;
}
else
pos += 1;
buf.position() = pos;
date = LocalDate(year, month, day);
return ReturnType(true);
}
else
return readDateTextFallback<ReturnType>(date, buf);
}
template <typename ReturnType = void>
inline ReturnType readDateTextImpl(DayNum & date, ReadBuffer & buf)
{
static constexpr bool throw_exception = std::is_same_v<ReturnType, void>;
LocalDate local_date;
if constexpr (throw_exception)
readDateTextImpl<ReturnType>(local_date, buf);
else if (!readDateTextImpl<ReturnType>(local_date, buf))
return false;
date = DateLUT::instance().makeDayNum(local_date.year(), local_date.month(), local_date.day());
return ReturnType(true);
}
template <typename ReturnType = void>
inline ReturnType readDateTextImpl(ExtendedDayNum & date, ReadBuffer & buf)
{
static constexpr bool throw_exception = std::is_same_v<ReturnType, void>;
LocalDate local_date;
if constexpr (throw_exception)
readDateTextImpl<ReturnType>(local_date, buf);
else if (!readDateTextImpl<ReturnType>(local_date, buf))
return false;
/// When the parameter is out of rule or out of range, Date32 uses 1925-01-01 as the default value (-DateLUT::instance().getDayNumOffsetEpoch(), -16436) and Date uses 1970-01-01.
date = DateLUT::instance().makeDayNum(local_date.year(), local_date.month(), local_date.day(), -static_cast<Int32>(DateLUT::instance().getDayNumOffsetEpoch()));
return ReturnType(true);
}
inline void readDateText(LocalDate & date, ReadBuffer & buf)
{
readDateTextImpl<void>(date, buf);
}
inline void readDateText(DayNum & date, ReadBuffer & buf)
{
readDateTextImpl<void>(date, buf);
}
inline void readDateText(ExtendedDayNum & date, ReadBuffer & buf)
{
readDateTextImpl<void>(date, buf);
}
inline bool tryReadDateText(LocalDate & date, ReadBuffer & buf)
{
return readDateTextImpl<bool>(date, buf);
}
inline bool tryReadDateText(DayNum & date, ReadBuffer & buf)
{
return readDateTextImpl<bool>(date, buf);
}
inline bool tryReadDateText(ExtendedDayNum & date, ReadBuffer & buf)
{
return readDateTextImpl<bool>(date, buf);
}
template <typename ReturnType = void>
inline ReturnType readUUIDTextImpl(UUID & uuid, ReadBuffer & buf)
{
static constexpr bool throw_exception = std::is_same_v<ReturnType, void>;
char s[36];
size_t size = buf.read(s, 32);
if (size == 32)
{
if (s[8] == '-')
{
size += buf.read(&s[32], 4);
if (size != 36)
{
s[size] = 0;
if constexpr (throw_exception)
{
throw ParsingException(std::string("Cannot parse uuid ") + s, ErrorCodes::CANNOT_PARSE_UUID);
}
else
{
return ReturnType(false);
}
}
parseUUID(reinterpret_cast<const UInt8 *>(s), std::reverse_iterator<UInt8 *>(reinterpret_cast<UInt8 *>(&uuid) + 16));
}
else
parseUUIDWithoutSeparator(reinterpret_cast<const UInt8 *>(s), std::reverse_iterator<UInt8 *>(reinterpret_cast<UInt8 *>(&uuid) + 16));
return ReturnType(true);
}
else
{
s[size] = 0;
if constexpr (throw_exception)
{
throw ParsingException(std::string("Cannot parse uuid ") + s, ErrorCodes::CANNOT_PARSE_UUID);
}
else
{
return ReturnType(false);
}
}
}
inline void readUUIDText(UUID & uuid, ReadBuffer & buf)
{
return readUUIDTextImpl<void>(uuid, buf);
}
inline bool tryReadUUIDText(UUID & uuid, ReadBuffer & buf)
{
return readUUIDTextImpl<bool>(uuid, buf);
}
template <typename T>
inline T parse(const char * data, size_t size);
template <typename T>
inline T parseFromString(const std::string_view & str)
{
return parse<T>(str.data(), str.size());
}
template <typename ReturnType = void>
ReturnType readDateTimeTextFallback(time_t & datetime, ReadBuffer & buf, const DateLUTImpl & date_lut);
/** In YYYY-MM-DD hh:mm:ss or YYYY-MM-DD format, according to specified time zone.
* As an exception, also supported parsing of unix timestamp in form of decimal number.
*/
template <typename ReturnType = void>
inline ReturnType readDateTimeTextImpl(time_t & datetime, ReadBuffer & buf, const DateLUTImpl & date_lut)
{
/// Optimistic path, when whole value is in buffer.
const char * s = buf.position();
/// YYYY-MM-DD hh:mm:ss
static constexpr auto DateTimeStringInputSize = 19;
bool optimistic_path_for_date_time_input = s + DateTimeStringInputSize <= buf.buffer().end();
if (optimistic_path_for_date_time_input)
{
if (s[4] < '0' || s[4] > '9')
{
UInt16 year = (s[0] - '0') * 1000 + (s[1] - '0') * 100 + (s[2] - '0') * 10 + (s[3] - '0');
UInt8 month = (s[5] - '0') * 10 + (s[6] - '0');
UInt8 day = (s[8] - '0') * 10 + (s[9] - '0');
UInt8 hour = (s[11] - '0') * 10 + (s[12] - '0');
UInt8 minute = (s[14] - '0') * 10 + (s[15] - '0');
UInt8 second = (s[17] - '0') * 10 + (s[18] - '0');
if (unlikely(year == 0))
datetime = 0;
else
datetime = date_lut.makeDateTime(year, month, day, hour, minute, second);
buf.position() += DateTimeStringInputSize;
return ReturnType(true);
}
else
/// Why not readIntTextUnsafe? Because for needs of AdFox, parsing of unix timestamp with leading zeros is supported: 000...NNNN.
return readIntTextImpl<time_t, ReturnType, ReadIntTextCheckOverflow::CHECK_OVERFLOW>(datetime, buf);
}
else
return readDateTimeTextFallback<ReturnType>(datetime, buf, date_lut);
}
template <typename ReturnType>
inline ReturnType readDateTimeTextImpl(DateTime64 & datetime64, UInt32 scale, ReadBuffer & buf, const DateLUTImpl & date_lut)
{
time_t whole;
if (!readDateTimeTextImpl<bool>(whole, buf, date_lut))
{
return ReturnType(false);
}
DB::DecimalUtils::DecimalComponents<DateTime64> components{static_cast<DateTime64::NativeType>(whole), 0};
if (!buf.eof() && *buf.position() == '.')
{
++buf.position();
/// Read digits, up to 'scale' positions.
for (size_t i = 0; i < scale; ++i)
{
if (!buf.eof() && isNumericASCII(*buf.position()))
{
components.fractional *= 10;
components.fractional += *buf.position() - '0';
++buf.position();
}
else
{
/// Adjust to scale.
components.fractional *= 10;
}
}
/// Ignore digits that are out of precision.
while (!buf.eof() && isNumericASCII(*buf.position()))
++buf.position();
}
/// 9908870400 is time_t value for 2184-01-01 UTC (a bit over the last year supported by DateTime64)
else if (whole >= 9908870400LL)
{
/// Unix timestamp with subsecond precision, already scaled to integer.
/// For disambiguation we support only time since 2001-09-09 01:46:40 UTC and less than 30 000 years in future.
for (size_t i = 0; i < scale; ++i)
{
components.fractional *= 10;
components.fractional += components.whole % 10;
components.whole /= 10;
}
}
datetime64 = DecimalUtils::decimalFromComponents<DateTime64>(components, scale);
return ReturnType(true);
}
inline void readDateTimeText(time_t & datetime, ReadBuffer & buf, const DateLUTImpl & time_zone = DateLUT::instance())
{
readDateTimeTextImpl<void>(datetime, buf, time_zone);
}
inline void readDateTime64Text(DateTime64 & datetime64, UInt32 scale, ReadBuffer & buf, const DateLUTImpl & date_lut = DateLUT::instance())
{
readDateTimeTextImpl<void>(datetime64, scale, buf, date_lut);
}
inline bool tryReadDateTimeText(time_t & datetime, ReadBuffer & buf, const DateLUTImpl & time_zone = DateLUT::instance())
{
return readDateTimeTextImpl<bool>(datetime, buf, time_zone);
}
inline bool tryReadDateTime64Text(DateTime64 & datetime64, UInt32 scale, ReadBuffer & buf, const DateLUTImpl & date_lut = DateLUT::instance())
{
return readDateTimeTextImpl<bool>(datetime64, scale, buf, date_lut);
}
inline void readDateTimeText(LocalDateTime & datetime, ReadBuffer & buf)
{
char s[19];
size_t size = buf.read(s, 19);
if (19 != size)
{
s[size] = 0;
throw ParsingException(std::string("Cannot parse datetime ") + s, ErrorCodes::CANNOT_PARSE_DATETIME);
}
datetime.year((s[0] - '0') * 1000 + (s[1] - '0') * 100 + (s[2] - '0') * 10 + (s[3] - '0'));
datetime.month((s[5] - '0') * 10 + (s[6] - '0'));
datetime.day((s[8] - '0') * 10 + (s[9] - '0'));
datetime.hour((s[11] - '0') * 10 + (s[12] - '0'));
datetime.minute((s[14] - '0') * 10 + (s[15] - '0'));
datetime.second((s[17] - '0') * 10 + (s[18] - '0'));
}
/// Generic methods to read value in native binary format.
template <typename T>
inline std::enable_if_t<is_arithmetic_v<T>, void>
readBinary(T & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(String & x, ReadBuffer & buf) { readStringBinary(x, buf); }
inline void readBinary(Int128 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(Int256 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(UInt128 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(UInt256 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(Decimal32 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(Decimal64 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(Decimal128 & x, ReadBuffer & buf) { readPODBinary(x, buf); }
inline void readBinary(Decimal256 & x, ReadBuffer & buf) { readPODBinary(x.value, buf); }
inline void readBinary(LocalDate & x, ReadBuffer & buf) { readPODBinary(x, buf); }
template <typename T>
inline std::enable_if_t<is_arithmetic_v<T> && (sizeof(T) <= 8), void>
readBinaryBigEndian(T & x, ReadBuffer & buf) /// Assuming little endian architecture.
{
readPODBinary(x, buf);
if constexpr (sizeof(x) == 1)
return;
else if constexpr (sizeof(x) == 2)
x = __builtin_bswap16(x);
else if constexpr (sizeof(x) == 4)
x = __builtin_bswap32(x);
else if constexpr (sizeof(x) == 8)
x = __builtin_bswap64(x);
}
template <typename T>
inline std::enable_if_t<is_big_int_v<T>, void>
readBinaryBigEndian(T & x, ReadBuffer & buf) /// Assuming little endian architecture.
{
for (size_t i = 0; i != std::size(x.items); ++i)
{
auto & item = x.items[std::size(x.items) - i - 1];
readBinaryBigEndian(item, buf);
}
}
/// Generic methods to read value in text tab-separated format.
inline void readText(is_integer auto & x, ReadBuffer & buf)
{
if constexpr (std::is_same_v<decltype(x), bool &>)
readBoolText(x, buf);
else
readIntText(x, buf);
}
inline bool tryReadText(is_integer auto & x, ReadBuffer & buf)
{
return tryReadIntText(x, buf);
}
inline void readText(is_floating_point auto & x, ReadBuffer & buf) { readFloatText(x, buf); }
inline void readText(String & x, ReadBuffer & buf) { readEscapedString(x, buf); }
inline void readText(LocalDate & x, ReadBuffer & buf) { readDateText(x, buf); }
inline void readText(LocalDateTime & x, ReadBuffer & buf) { readDateTimeText(x, buf); }
inline void readText(UUID & x, ReadBuffer & buf) { readUUIDText(x, buf); }
/// Generic methods to read value in text format,
/// possibly in single quotes (only for data types that use quotes in VALUES format of INSERT statement in SQL).
template <typename T>
inline std::enable_if_t<is_arithmetic_v<T>, void>
readQuoted(T & x, ReadBuffer & buf) { readText(x, buf); }
inline void readQuoted(String & x, ReadBuffer & buf) { readQuotedString(x, buf); }
inline void readQuoted(LocalDate & x, ReadBuffer & buf)
{
assertChar('\'', buf);
readDateText(x, buf);
assertChar('\'', buf);
}
inline void readQuoted(LocalDateTime & x, ReadBuffer & buf)
{
assertChar('\'', buf);
readDateTimeText(x, buf);
assertChar('\'', buf);
}
inline void readQuoted(UUID & x, ReadBuffer & buf)
{
assertChar('\'', buf);
readUUIDText(x, buf);
assertChar('\'', buf);
}
/// Same as above, but in double quotes.
template <typename T>
inline std::enable_if_t<is_arithmetic_v<T>, void>
readDoubleQuoted(T & x, ReadBuffer & buf) { readText(x, buf); }
inline void readDoubleQuoted(String & x, ReadBuffer & buf) { readDoubleQuotedString(x, buf); }
inline void readDoubleQuoted(LocalDate & x, ReadBuffer & buf)
{
assertChar('"', buf);
readDateText(x, buf);
assertChar('"', buf);
}
inline void readDoubleQuoted(LocalDateTime & x, ReadBuffer & buf)
{
assertChar('"', buf);
readDateTimeText(x, buf);
assertChar('"', buf);
}
/// CSV, for numbers, dates: quotes are optional, no special escaping rules.
template <typename T>
inline void readCSVSimple(T & x, ReadBuffer & buf)
{
if (buf.eof())
throwReadAfterEOF();
char maybe_quote = *buf.position();
if (maybe_quote == '\'' || maybe_quote == '\"')
++buf.position();
readText(x, buf);
if (maybe_quote == '\'' || maybe_quote == '\"')
assertChar(maybe_quote, buf);
}
template <typename T>
inline std::enable_if_t<is_arithmetic_v<T>, void>
readCSV(T & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(String & x, ReadBuffer & buf, const FormatSettings::CSV & settings) { readCSVString(x, buf, settings); }
inline void readCSV(LocalDate & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(LocalDateTime & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(UUID & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(UInt128 & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(Int128 & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(UInt256 & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
inline void readCSV(Int256 & x, ReadBuffer & buf) { readCSVSimple(x, buf); }
template <typename T>
void readBinary(std::vector<T> & x, ReadBuffer & buf)
{
size_t size = 0;
readVarUInt(size, buf);
if (size > DEFAULT_MAX_STRING_SIZE)
throw Poco::Exception("Too large vector size.");
x.resize(size);
for (size_t i = 0; i < size; ++i)
readBinary(x[i], buf);
}
template <typename T>
void readQuoted(std::vector<T> & x, ReadBuffer & buf)
{
bool first = true;
assertChar('[', buf);
while (!buf.eof() && *buf.position() != ']')
{
if (!first)
{
if (*buf.position() == ',')
++buf.position();
else
throw ParsingException("Cannot read array from text", ErrorCodes::CANNOT_READ_ARRAY_FROM_TEXT);
}
first = false;
x.push_back(T());
readQuoted(x.back(), buf);
}
assertChar(']', buf);
}
template <typename T>
void readDoubleQuoted(std::vector<T> & x, ReadBuffer & buf)
{
bool first = true;
assertChar('[', buf);
while (!buf.eof() && *buf.position() != ']')
{
if (!first)
{
if (*buf.position() == ',')
++buf.position();
else
throw ParsingException("Cannot read array from text", ErrorCodes::CANNOT_READ_ARRAY_FROM_TEXT);
}
first = false;
x.push_back(T());
readDoubleQuoted(x.back(), buf);
}
assertChar(']', buf);
}
template <typename T>
void readText(std::vector<T> & x, ReadBuffer & buf)
{
readQuoted(x, buf);
}
/// Skip whitespace characters.
inline void skipWhitespaceIfAny(ReadBuffer & buf, bool one_line = false)
{
if (!one_line)
while (!buf.eof() && isWhitespaceASCII(*buf.position()))
++buf.position();
else
while (!buf.eof() && isWhitespaceASCIIOneLine(*buf.position()))
++buf.position();
}
/// Skips json value.
void skipJSONField(ReadBuffer & buf, const StringRef & name_of_field);
/** Read serialized exception.
* During serialization/deserialization some information is lost
* (type is cut to base class, 'message' replaced by 'displayText', and stack trace is appended to 'message')
* Some additional message could be appended to exception (example: you could add information about from where it was received).
*/
Exception readException(ReadBuffer & buf, const String & additional_message = "", bool remote_exception = false);
void readAndThrowException(ReadBuffer & buf, const String & additional_message = "");
/** Helper function for implementation.
*/
template <ReadIntTextCheckOverflow check_overflow = ReadIntTextCheckOverflow::CHECK_OVERFLOW, typename T>
static inline const char * tryReadIntText(T & x, const char * pos, const char * end)
{
ReadBufferFromMemory in(pos, end - pos);
tryReadIntText<check_overflow>(x, in);
return pos + in.count();
}
/// Convenient methods for reading something from string in text format.
template <typename T>
inline T parse(const char * data, size_t size)
{
T res;
ReadBufferFromMemory buf(data, size);
readText(res, buf);
return res;
}
template <typename T>
inline bool tryParse(T & res, const char * data, size_t size)
{
ReadBufferFromMemory buf(data, size);
return tryReadText(res, buf);
}
template <typename T>
inline void readTextWithSizeSuffix(T & x, ReadBuffer & buf) { readText(x, buf); }
template <is_integer T>
inline void readTextWithSizeSuffix(T & x, ReadBuffer & buf)
{
readIntText(x, buf);
if (buf.eof())
return;
/// Updates x depending on the suffix
auto finish = [&buf, &x] (UInt64 base, int power_of_two) mutable
{
++buf.position();
if (buf.eof())
{
x *= base; /// For decimal suffixes, such as k, M, G etc.
}
else if (*buf.position() == 'i')
{
x = (x << power_of_two); // NOLINT /// For binary suffixes, such as ki, Mi, Gi, etc.
++buf.position();
}
return;
};
switch (*buf.position())
{
case 'k': [[fallthrough]];
case 'K':
finish(1000, 10);
break;
case 'M':
finish(1000000, 20);
break;
case 'G':
finish(1000000000, 30);
break;
case 'T':
finish(1000000000000ULL, 40);
break;
default:
return;
}
return;
}
/// Read something from text format and trying to parse the suffix.
/// If the suffix is not valid gives an error
/// For example: 723145 -- ok, 213MB -- not ok, but 213Mi -- ok
template <typename T>
inline T parseWithSizeSuffix(const char * data, size_t size)
{
T res;
ReadBufferFromMemory buf(data, size);
readTextWithSizeSuffix(res, buf);
assertEOF(buf);
return res;
}
template <typename T>
inline T parseWithSizeSuffix(const std::string_view & s)
{
return parseWithSizeSuffix<T>(s.data(), s.size());
}
template <typename T>
inline T parseWithSizeSuffix(const char * data)
{
return parseWithSizeSuffix<T>(data, strlen(data));
}
template <typename T>
inline T parse(const char * data)
{
return parse<T>(data, strlen(data));
}
template <typename T>
inline T parse(const String & s)
{
return parse<T>(s.data(), s.size());
}
template <typename T>
inline bool tryParse(T & res, const char * data)
{
return tryParse(res, data, strlen(data));
}
template <typename T>
inline bool tryParse(T & res, const String & s)
{
return tryParse(res, s.data(), s.size());
}
/** Skip UTF-8 BOM if it is under cursor.
* As BOM is usually located at start of stream, and buffer size is usually larger than three bytes,
* the function expects, that all three bytes of BOM is fully in buffer (otherwise it don't skip anything).
*/
inline void skipBOMIfExists(ReadBuffer & buf)
{
if (!buf.eof()
&& buf.position() + 3 < buf.buffer().end()
&& buf.position()[0] == '\xEF'
&& buf.position()[1] == '\xBB'
&& buf.position()[2] == '\xBF')
{
buf.position() += 3;
}
}
/// Skip to next character after next \n. If no \n in stream, skip to end.
void skipToNextLineOrEOF(ReadBuffer & buf);
/// Skip to next character after next \r. If no \r in stream, skip to end.
void skipToCarriageReturnOrEOF(ReadBuffer & buf);
/// Skip to next character after next unescaped \n. If no \n in stream, skip to end. Does not throw on invalid escape sequences.
void skipToUnescapedNextLineOrEOF(ReadBuffer & buf);
/** This function just copies the data from buffer's internal position (in.position())
* to current position (from arguments) into memory.
*/
void saveUpToPosition(ReadBuffer & in, Memory<Allocator<false>> & memory, char * current);
/** This function is negative to eof().
* In fact it returns whether the data was loaded to internal ReadBuffers's buffer or not.
* And saves data from buffer's position to current if there is no pending data in buffer.
* Why we have to use this strange function? Consider we have buffer's internal position in the middle
* of our buffer and the current cursor in the end of the buffer. When we call eof() it calls next().
* And this function can fill the buffer with new data, so we will lose the data from previous buffer state.
*/
bool loadAtPosition(ReadBuffer & in, Memory<Allocator<false>> & memory, char * & current);
struct PcgDeserializer
{
static void deserializePcg32(pcg32_fast & rng, ReadBuffer & buf)
{
decltype(rng.state_) multiplier, increment, state;
readText(multiplier, buf);
assertChar(' ', buf);
readText(increment, buf);
assertChar(' ', buf);
readText(state, buf);
if (multiplier != rng.multiplier())
throw Exception(ErrorCodes::INCORRECT_DATA, "Incorrect multiplier in pcg32: expected {}, got {}", rng.multiplier(), multiplier);
if (increment != rng.increment())
throw Exception(ErrorCodes::INCORRECT_DATA, "Incorrect increment in pcg32: expected {}, got {}", rng.increment(), increment);
rng.state_ = state;
}
};
}
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