my_decimal.h File Reference

It is interface module to fixed precision decimals library. More...

#include <assert.h>
#include <stdlib.h>
#include <sys/types.h>
#include <algorithm>
#include "decimal.h"
#include "my_inttypes.h"
#include "my_macros.h"
#include "my_time_t.h"
#include "mysql/strings/dtoa.h"
#include "mysql/strings/m_ctype.h"

Go to the source code of this file.

Classes
class	my_decimal
	my_decimal class limits 'decimal_t' type to what we need in MySQL. More...

Functions
int	my_decimal_int_part (uint precision, uint decimals)
void	print_decimal (const my_decimal *dec)
void	print_decimal_buff (const my_decimal *dec, const uchar *ptr, int length)
const char *	dbug_decimal_as_string (char *buff, const my_decimal *val)
bool	str_set_decimal (uint mask, const my_decimal *val, String *str, const CHARSET_INFO *cs, uint decimals)
	Converting decimal to string with character set conversion. More...
void	max_my_decimal (my_decimal *to, int precision, int frac)
void	max_internal_decimal (my_decimal *to)
int	check_result_and_overflow (uint mask, int result, my_decimal *val)
uint	my_decimal_length_to_precision (uint length, uint scale, bool unsigned_flag)
uint32	my_decimal_precision_to_length_no_truncation (uint precision, uint8 scale, bool unsigned_flag)
uint32	my_decimal_precision_to_length (uint precision, uint8 scale, bool unsigned_flag)
int	my_decimal_string_length (const my_decimal *d)
int	my_decimal_get_binary_size (uint precision, uint scale)
void	my_decimal2decimal (const my_decimal *from, my_decimal *to)
int	my_decimal2binary (uint mask, const my_decimal *d, uchar *bin, int prec, int scale)
int	binary2my_decimal (uint mask, const uchar *bin, my_decimal *d, int prec, int scale)
int	binary2my_decimal (uint mask, const uchar *bin, my_decimal *d, int prec, int scale, bool keep_prec)
	Decode DECIMAL from binary form. More...
int	my_decimal_set_zero (my_decimal *d)
bool	my_decimal_is_zero (const my_decimal *decimal_value)
int	my_decimal_round (uint mask, const my_decimal *from, int scale, bool truncate, my_decimal *to)
int	my_decimal_floor (uint mask, const my_decimal *from, my_decimal *to)
int	my_decimal_ceiling (uint mask, const my_decimal *from, my_decimal *to)
int	my_decimal2string (uint mask, const my_decimal *d, uint fixed_prec, uint fixed_dec, String *str)
	Converting decimal to string. More...
int	my_decimal2string (uint mask, const my_decimal *d, String *str)
int	my_decimal2int (uint mask, const my_decimal *d, bool unsigned_flag, longlong *l)
int	my_decimal2double (uint, const my_decimal *d, double *result)
int	my_decimal2lldiv_t (uint mask, const my_decimal *d, lldiv_t *to)
int	str2my_decimal (uint mask, const char *str, my_decimal *d, const char **end)
int	str2my_decimal (uint mask, const char *from, size_t length, const CHARSET_INFO *charset, my_decimal *decimal_value)
my_decimal *	date2my_decimal (const MYSQL_TIME *ltime, my_decimal *dec)
	Convert datetime value to my_decimal in format YYYYMMDDhhmmss.ffffff. More...
my_decimal *	time2my_decimal (const MYSQL_TIME *ltime, my_decimal *dec)
	Convert time value to my_decimal in format hhmmss.ffffff. More...
my_decimal *	timeval2my_decimal (const my_timeval *tm, my_decimal *dec)
	Convert timeval value to my_decimal. More...
int	double2my_decimal (uint mask, double val, my_decimal *d)
int	int2my_decimal (uint mask, longlong i, bool unsigned_flag, my_decimal *d)
void	my_decimal_neg (decimal_t *arg)
int	my_decimal_add (uint mask, my_decimal *res, const my_decimal *a, const my_decimal *b)
int	my_decimal_sub (uint mask, my_decimal *res, const my_decimal *a, const my_decimal *b)
int	my_decimal_mul (uint mask, my_decimal *res, const my_decimal *a, const my_decimal *b)
int	my_decimal_div (uint mask, my_decimal *res, const my_decimal *a, const my_decimal *b, int div_scale_inc)
int	my_decimal_mod (uint mask, my_decimal *res, const my_decimal *a, const my_decimal *b)
int	my_decimal_cmp (const my_decimal *a, const my_decimal *b)
bool	operator< (const my_decimal &lhs, const my_decimal &rhs)
bool	operator!= (const my_decimal &lhs, const my_decimal &rhs)
int	my_decimal_intg (const my_decimal *a)
void	my_decimal_trim (ulong *precision, uint *scale)

Variables
static constexpr int	DECIMAL_LONGLONG_DIGITS {22}
static constexpr int	DECIMAL_BUFF_LENGTH {9}
	maximum length of buffer in our big digits (uint32). More...
static constexpr int	DECIMAL_MAX_POSSIBLE_PRECISION {DECIMAL_BUFF_LENGTH * 9}
	the number of digits that my_decimal can possibly contain More...
static constexpr int	DECIMAL_MAX_PRECISION
	maximum guaranteed precision of number in decimal digits (number of our digits * number of decimal digits in one our big digit - number of decimal digits in one our big digit decreased by 1 (because we always put decimal point on the border of our big digits)) More...
static constexpr int	DECIMAL_MAX_STR_LENGTH {DECIMAL_MAX_POSSIBLE_PRECISION + 2}
	maximum length of string representation (number of maximum decimal digits + 1 position for sign + 1 position for decimal point, no terminator) More...
static constexpr int	DECIMAL_MAX_FIELD_SIZE {DECIMAL_MAX_PRECISION}
	maximum size of packet length. More...
my_decimal	decimal_zero

Detailed Description

It is interface module to fixed precision decimals library.

Most functions use 'uint mask' as parameter, if during operation error which fit in this mask is detected then it will be processed automatically here. (errors are E_DEC_* constants, see include/decimal.h)

Most function are just inline wrappers around library calls

Function Documentation

binary2my_decimal() [1/2]

int binary2my_decimal ( uint  mask, const uchar *  bin, my_decimal *  d, int  prec, int  scale  )

inline

binary2my_decimal() [2/2]

int binary2my_decimal ( uint  mask, const uchar *  bin, my_decimal *  d, int  prec, int  scale, bool  keep_prec  )

inline

Decode DECIMAL from binary form.

Parameters

mask	Error mask
bin	Binary string to decode
d	[out] DECIMAL buffer
prec	Precision of stored value
scale	Scale of stored value
keep_prec	Whether to keep stored value's precision

Returns

conversion error

check_result_and_overflow()

int check_result_and_overflow ( uint  mask, int  result, my_decimal *  val  )

inline

date2my_decimal()

my_decimal * date2my_decimal	(	const MYSQL_TIME *	ltime,
		my_decimal *	dec
	)

Convert datetime value to my_decimal in format YYYYMMDDhhmmss.ffffff.

Parameters

ltime	Date value to convert from.
dec	Decimal value to convert to.

dbug_decimal_as_string()

const char * dbug_decimal_as_string	(	char *	buff,
		const my_decimal *	val
	)

double2my_decimal()

int double2my_decimal ( uint  mask, double  val, my_decimal *  d  )

inline

int2my_decimal()

int int2my_decimal ( uint  mask, longlong  i, bool  unsigned_flag, my_decimal *  d  )

inline

max_internal_decimal()

void max_internal_decimal ( my_decimal *  to )

inline

max_my_decimal()

void max_my_decimal ( my_decimal *  to, int  precision, int  frac  )

inline

my_decimal2binary()

int my_decimal2binary	(	uint	mask,
		const my_decimal *	d,
		uchar *	bin,
		int	prec,
		int	scale
	)

my_decimal2decimal()

void my_decimal2decimal ( const my_decimal *  from, my_decimal *  to  )

inline

my_decimal2double()

int my_decimal2double ( uint  , const my_decimal *  d, double *  result  )

inline

my_decimal2int()

int my_decimal2int ( uint  mask, const my_decimal *  d, bool  unsigned_flag, longlong *  l  )

inline

my_decimal2lldiv_t()

int my_decimal2lldiv_t ( uint  mask, const my_decimal *  d, lldiv_t *  to  )

inline

my_decimal2string() [1/2]

int my_decimal2string ( uint  mask, const my_decimal *  d, String *  str  )

inline

my_decimal2string() [2/2]

int my_decimal2string	(	uint	mask,
		const my_decimal *	d,
		uint	fixed_prec,
		uint	fixed_dec,
		String *	str
	)

Converting decimal to string.

Convert given my_decimal to String; allocate buffer as needed.

Parameters

[in]	mask	what problems to warn on (mask of E_DEC_* values)
[in]	d	the decimal to print
[in]	fixed_prec	overall number of digits if ZEROFILL, 0 otherwise
[in]	fixed_dec	number of decimal places (if fixed_prec != 0)
[out]	str	where to store the resulting string

Returns

error code

Return values

E_DEC_OK	ok
E_DEC_TRUNCATED	truncated
E_DEC_OVERFLOW	overflow
E_DEC_OOM	out-of-memory

my_decimal_add()

int my_decimal_add ( uint  mask, my_decimal *  res, const my_decimal *  a, const my_decimal *  b  )

inline

my_decimal_ceiling()

int my_decimal_ceiling ( uint  mask, const my_decimal *  from, my_decimal *  to  )

inline

my_decimal_cmp()

int my_decimal_cmp ( const my_decimal *  a, const my_decimal *  b  )

inline

Return values

-1	if a < b
1	if a > b
0	if a == b

my_decimal_div()

int my_decimal_div ( uint  mask, my_decimal *  res, const my_decimal *  a, const my_decimal *  b, int  div_scale_inc  )

inline

my_decimal_floor()

int my_decimal_floor ( uint  mask, const my_decimal *  from, my_decimal *  to  )

inline

my_decimal_get_binary_size()

int my_decimal_get_binary_size ( uint  precision, uint  scale  )

inline

my_decimal_int_part()

int my_decimal_int_part ( uint  precision, uint  decimals  )

inline

my_decimal_intg()

int my_decimal_intg ( const my_decimal *  a )

inline

my_decimal_is_zero()

bool my_decimal_is_zero ( const my_decimal *  decimal_value )

inline

my_decimal_length_to_precision()

uint my_decimal_length_to_precision ( uint  length, uint  scale, bool  unsigned_flag  )

inline

my_decimal_mod()

int my_decimal_mod ( uint  mask, my_decimal *  res, const my_decimal *  a, const my_decimal *  b  )

inline

my_decimal_mul()

int my_decimal_mul ( uint  mask, my_decimal *  res, const my_decimal *  a, const my_decimal *  b  )

inline

my_decimal_neg()

void my_decimal_neg ( decimal_t *  arg )

inline

my_decimal_precision_to_length()

uint32 my_decimal_precision_to_length ( uint  precision, uint8  scale, bool  unsigned_flag  )

inline

my_decimal_precision_to_length_no_truncation()

uint32 my_decimal_precision_to_length_no_truncation ( uint  precision, uint8  scale, bool  unsigned_flag  )

inline

my_decimal_round()

int my_decimal_round ( uint  mask, const my_decimal *  from, int  scale, bool  truncate, my_decimal *  to  )

inline

my_decimal_set_zero()

int my_decimal_set_zero ( my_decimal *  d )

inline

my_decimal_string_length()

int my_decimal_string_length ( const my_decimal *  d )

inline

my_decimal_sub()

int my_decimal_sub ( uint  mask, my_decimal *  res, const my_decimal *  a, const my_decimal *  b  )

inline

my_decimal_trim()

void my_decimal_trim	(	ulong *	precision,
		uint *	scale
	)

operator!=()

bool operator!= ( const my_decimal &  lhs, const my_decimal &  rhs  )

inline

operator<()

bool operator< ( const my_decimal &  lhs, const my_decimal &  rhs  )

inline

print_decimal()

void print_decimal

(

const my_decimal *

dec

)

print_decimal_buff()

void print_decimal_buff	(	const my_decimal *	dec,
		const uchar *	ptr,
		int	length
	)

str2my_decimal() [1/2]

int str2my_decimal	(	uint	mask,
		const char *	from,
		size_t	length,
		const CHARSET_INFO *	charset,
		my_decimal *	decimal_value
	)

str2my_decimal() [2/2]

int str2my_decimal ( uint  mask, const char *  str, my_decimal *  d, const char **  end  )

inline

str_set_decimal()

bool str_set_decimal	(	uint	mask,
		const my_decimal *	val,
		String *	str,
		const CHARSET_INFO *	cs,
		uint	decimals
	)

Converting decimal to string with character set conversion.

Convert given my_decimal to String; allocate buffer as needed.

Parameters

[in]	mask	what problems to warn on (mask of E_DEC_* values)
[in]	val	the decimal to print
[out]	str	where to store the resulting string
[in]	cs	character set
[in]	decimals	round to desired number of decimals

Returns

error code

Return values

E_DEC_OK	ok
E_DEC_TRUNCATED	truncated
E_DEC_OVERFLOW	overflow
E_DEC_OOM	out-of-memory

Would be great to make it a method of the String class, but this would need to include my_decimal.h from sql_string.h and sql_string.cc, which is not desirable.

time2my_decimal()

my_decimal * time2my_decimal	(	const MYSQL_TIME *	ltime,
		my_decimal *	dec
	)

Convert time value to my_decimal in format hhmmss.ffffff.

Parameters

ltime	Date value to convert from.
dec	Decimal value to convert to.

timeval2my_decimal()

my_decimal * timeval2my_decimal	(	const my_timeval *	tm,
		my_decimal *	dec
	)

Convert timeval value to my_decimal.

Variable Documentation

DECIMAL_BUFF_LENGTH

constexpr int DECIMAL_BUFF_LENGTH {9}

staticconstexpr

maximum length of buffer in our big digits (uint32).

DECIMAL_LONGLONG_DIGITS

constexpr int DECIMAL_LONGLONG_DIGITS {22}

staticconstexpr

DECIMAL_MAX_FIELD_SIZE

constexpr int DECIMAL_MAX_FIELD_SIZE {DECIMAL_MAX_PRECISION}

staticconstexpr

maximum size of packet length.

DECIMAL_MAX_POSSIBLE_PRECISION

constexpr int DECIMAL_MAX_POSSIBLE_PRECISION {DECIMAL_BUFF_LENGTH * 9}

staticconstexpr

the number of digits that my_decimal can possibly contain

DECIMAL_MAX_PRECISION

constexpr int DECIMAL_MAX_PRECISION

staticconstexpr

Initial value:

{DECIMAL_MAX_POSSIBLE_PRECISION -
                                           8 * 2}

maximum guaranteed precision of number in decimal digits (number of our digits * number of decimal digits in one our big digit - number of decimal digits in one our big digit decreased by 1 (because we always put decimal point on the border of our big digits))

DECIMAL_MAX_STR_LENGTH

constexpr int DECIMAL_MAX_STR_LENGTH {DECIMAL_MAX_POSSIBLE_PRECISION + 2}

staticconstexpr

maximum length of string representation (number of maximum decimal digits + 1 position for sign + 1 position for decimal point, no terminator)

decimal_zero

my_decimal decimal_zero

extern