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/* Copyright (C) 2000 Sergei Golubchik
*/
#ifndef _decimal_h
#define _decimal_h
typedef enum {TRUNCATE=0, HALF_EVEN, HALF_UP, CEILING, FLOOR} decimal_round_mode;
typedef int32 decimal_digit;
typedef struct st_decimal {
int intg, frac, len;
my_bool sign;
decimal_digit *buf;
} decimal;
int decimal2string(decimal *from, char *to, int *to_len);
int bin2decimal(const char *from, decimal *to, int precision, int scale);
int decimal_size(int precision, int scale);
int decimal_bin_size(int precision, int scale);
int decimal_result_size(decimal *from1, decimal *from2, char op, int param);
/* set a decimal to zero */
#define decimal_make_zero(dec) do { \
(dec)->buf[0]=0; \
(dec)->intg=1; \
(dec)->frac=0; \
(dec)->sign=0; \
} while(0)
/*
returns the length of the buffer to hold string representation
of the decimal (including decimal dot, possible sign and \0)
*/
#define decimal_string_size(dec) ((dec)->intg + (dec)->frac + ((dec)->frac > 0) + 2)
/* negate a decimal */
#define decimal_neg(dec) do { (dec)->sign^=1; } while(0)
/*
conventions:
decimal_smth() == 0 -- everything's ok
decimal_smth() <= 1 -- result is usable, but precision loss is possible
decimal_smth() <= 2 -- result can be unusable, most significant digits
could've been lost
decimal_smth() > 2 -- no result was generated
*/
#define E_DEC_OK 0
#define E_DEC_TRUNCATED 1
#define E_DEC_OVERFLOW 2
#define E_DEC_DIV_ZERO 4
#define E_DEC_BAD_NUM 8
#define E_DEC_OOM 16
#define E_DEC_ERROR 31
#define E_DEC_FATAL_ERROR 30
#endif
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