my_decimal.cc

/* Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#include <my_global.h>
#include "sql_priv.h"
#include <time.h>

#ifndef MYSQL_CLIENT
#include "sql_class.h"                          // THD
#endif

#ifndef MYSQL_CLIENT

int decimal_operation_results(int result)
{
  switch (result) {
  case E_DEC_OK:
    break;
  case E_DEC_TRUNCATED:
    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
                        WARN_DATA_TRUNCATED, ER(WARN_DATA_TRUNCATED),
                        "", (long)-1);
    break;
  case E_DEC_OVERFLOW:
    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
                        ER_TRUNCATED_WRONG_VALUE,
                        ER(ER_TRUNCATED_WRONG_VALUE),
                        "DECIMAL", "");
    break;
  case E_DEC_DIV_ZERO:
    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
                        ER_DIVISION_BY_ZERO, ER(ER_DIVISION_BY_ZERO));
    break;
  case E_DEC_BAD_NUM:
    push_warning_printf(current_thd, Sql_condition::WARN_LEVEL_WARN,
                        ER_TRUNCATED_WRONG_VALUE_FOR_FIELD,
                        ER(ER_TRUNCATED_WRONG_VALUE_FOR_FIELD),
                        "decimal", "", "", (long)-1);
    break;
  case E_DEC_OOM:
    my_error(ER_OUT_OF_RESOURCES, MYF(0));
    break;
  default:
    DBUG_ASSERT(0);
  }
  return result;
}


int my_decimal2string(uint mask, const my_decimal *d,
                      uint fixed_prec, uint fixed_dec,
                      char filler, String *str)
{
  /*
    Calculate the size of the string: For DECIMAL(a,b), fixed_prec==a
    holds true iff the type is also ZEROFILL, which in turn implies
    UNSIGNED. Hence the buffer for a ZEROFILLed value is the length
    the user requested, plus one for a possible decimal point, plus
    one if the user only wanted decimal places, but we force a leading
    zero on them, plus one for the '\0' terminator. Because the type
    is implicitly UNSIGNED, we do not need to reserve a character for
    the sign. For all other cases, fixed_prec will be 0, and
    my_decimal_string_length() will be called instead to calculate the
    required size of the buffer.
  */
  int length= (fixed_prec
               ? (fixed_prec + ((fixed_prec == fixed_dec) ? 1 : 0) + 1 + 1)
               : my_decimal_string_length(d));
  int result;
  if (str->alloc(length))
    return check_result(mask, E_DEC_OOM);
  result= decimal2string((decimal_t*) d, (char*) str->ptr(),
                         &length, (int)fixed_prec, fixed_dec,
                         filler);
  str->length(length);
  str->set_charset(&my_charset_numeric);
  return check_result(mask, result);
}


bool
str_set_decimal(uint mask, const my_decimal *val,
                uint fixed_prec, uint fixed_dec, char filler,
                String *str, const CHARSET_INFO *cs)
{
  if (!(cs->state & MY_CS_NONASCII))
  {
    /* For ASCII-compatible character sets we can use my_decimal2string */
    my_decimal2string(mask, val, fixed_prec, fixed_dec, filler, str);
    str->set_charset(cs);
    return FALSE;
  }
  else
  {
    /*
      For ASCII-incompatible character sets (like UCS2) we
      call my_decimal2string() on a temporary buffer first,
      and then convert the result to the target character
      with help of str->copy().
    */
    uint errors;
    char buf[DECIMAL_MAX_STR_LENGTH];
    String tmp(buf, sizeof(buf), &my_charset_latin1);
    my_decimal2string(mask, val, fixed_prec, fixed_dec, filler, &tmp);
    return str->copy(tmp.ptr(), tmp.length(), &my_charset_latin1, cs, &errors);
  }
}


/*
  Convert from decimal to binary representation

  SYNOPSIS
    my_decimal2binary()
    mask        error processing mask
    d           number for conversion
    bin         pointer to buffer where to write result
    prec        overall number of decimal digits
    scale       number of decimal digits after decimal point

  NOTE
    Before conversion we round number if it need but produce truncation
    error in this case

  RETURN
    E_DEC_OK
    E_DEC_TRUNCATED
    E_DEC_OVERFLOW
*/

int my_decimal2binary(uint mask, const my_decimal *d, uchar *bin, int prec,
                      int scale)
{
  int err1= E_DEC_OK, err2;
  my_decimal rounded;
  my_decimal2decimal(d, &rounded);
  rounded.frac= decimal_actual_fraction(&rounded);
  if (scale < rounded.frac)
  {
    err1= E_DEC_TRUNCATED;
    /* decimal_round can return only E_DEC_TRUNCATED */
    decimal_round(&rounded, &rounded, scale, HALF_UP);
  }
  err2= decimal2bin(&rounded, bin, prec, scale);
  if (!err2)
    err2= err1;
  return check_result(mask, err2);
}


/*
  Convert string for decimal when string can be in some multibyte charset

  SYNOPSIS
    str2my_decimal()
    mask            error processing mask
    from            string to process
    length          length of given string
    charset         charset of given string
    decimal_value   buffer for result storing

  RESULT
    E_DEC_OK
    E_DEC_TRUNCATED
    E_DEC_OVERFLOW
    E_DEC_BAD_NUM
    E_DEC_OOM
*/

int str2my_decimal(uint mask, const char *from, uint length,
                   const CHARSET_INFO *charset, my_decimal *decimal_value)
{
  char *end, *from_end;
  int err;
  char buff[STRING_BUFFER_USUAL_SIZE];
  String tmp(buff, sizeof(buff), &my_charset_bin);
  if (charset->mbminlen > 1)
  {
    uint dummy_errors;
    tmp.copy(from, length, charset, &my_charset_latin1, &dummy_errors);
    from= tmp.ptr();
    length=  tmp.length();
    charset= &my_charset_bin;
  }
  from_end= end= (char*) from+length;
  err= string2decimal((char *)from, (decimal_t*) decimal_value, &end);
  if (end != from_end && !err)
  {
    /* Give warning if there is something other than end space */
    for ( ; end < from_end; end++)
    {
      if (!my_isspace(&my_charset_latin1, *end))
      {
        err= E_DEC_TRUNCATED;
        break;
      }
    }
  }
  check_result_and_overflow(mask, err, decimal_value);
  return err;
}


static my_decimal *lldiv_t2my_decimal(const lldiv_t *lld, bool neg,
                                      my_decimal *dec)
{
  if (int2my_decimal(E_DEC_FATAL_ERROR, lld->quot, FALSE, dec))
    return dec;
  if (neg)
    decimal_neg((decimal_t *) dec);
  if (lld->rem)
  {
    dec->buf[(dec->intg-1) / 9 + 1]= lld->rem;
    dec->frac= 6;
  }
  return dec;
}


my_decimal *date2my_decimal(const MYSQL_TIME *ltime, my_decimal *dec)
{
  lldiv_t lld;
  lld.quot= ltime->time_type > MYSQL_TIMESTAMP_DATE ?
            TIME_to_ulonglong_datetime(ltime) :
            TIME_to_ulonglong_date(ltime);
  lld.rem= (longlong) ltime->second_part * 1000;
  return lldiv_t2my_decimal(&lld, ltime->neg, dec);
}


my_decimal *time2my_decimal(const MYSQL_TIME *ltime, my_decimal *dec)
{
  lldiv_t lld;
  lld.quot= TIME_to_ulonglong_time(ltime);
  lld.rem= (longlong) ltime->second_part * 1000;
  return lldiv_t2my_decimal(&lld, ltime->neg, dec);
}


my_decimal *timeval2my_decimal(const struct timeval *tm, my_decimal *dec)
{
  lldiv_t lld;
  lld.quot= tm->tv_sec;
  lld.rem= (longlong) tm->tv_usec * 1000;
  return lldiv_t2my_decimal(&lld, 0, dec);
}


void my_decimal_trim(ulong *precision, uint *scale)
{
  if (!(*precision) && !(*scale))
  {
    *precision= 10;
    *scale= 0;
    return;
  }
}


#ifndef DBUG_OFF
/* routines for debugging print */

#define DIG_PER_DEC1 9
#define ROUND_UP(X)  (((X)+DIG_PER_DEC1-1)/DIG_PER_DEC1)

/* print decimal */
void
print_decimal(const my_decimal *dec)
{
  int i, end;
  char buff[512], *pos;
  pos= buff;
  pos+= sprintf(buff, "Decimal: sign: %d  intg: %d  frac: %d  { ",
                dec->sign(), dec->intg, dec->frac);
  end= ROUND_UP(dec->frac)+ROUND_UP(dec->intg)-1;
  for (i=0; i < end; i++)
    pos+= sprintf(pos, "%09d, ", dec->buf[i]);
  pos+= sprintf(pos, "%09d }\n", dec->buf[i]);
  fputs(buff, DBUG_FILE);
}


/* print decimal with its binary representation */
void
print_decimal_buff(const my_decimal *dec, const uchar* ptr, int length)
{
  print_decimal(dec);
  fprintf(DBUG_FILE, "Record: ");
  for (int i= 0; i < length; i++)
  {
    fprintf(DBUG_FILE, "%02X ", (uint)((uchar *)ptr)[i]);
  }
  fprintf(DBUG_FILE, "\n");
}


const char *dbug_decimal_as_string(char *buff, const my_decimal *val)
{
  int length= DECIMAL_MAX_STR_LENGTH + 1;     /* minimum size for buff */
  if (!val)
    return "NULL";
  (void)decimal2string((decimal_t*) val, buff, &length, 0,0,0);
  return buff;
}

#endif /*DBUG_OFF*/


#endif /*MYSQL_CLIENT*/