Function decimal2string

strings/decimal.c:335–446

*/

int decimal2string(const decimal_t *from, char *to, int *to_len,
                   decimal_digits_t fixed_precision,
                   decimal_digits_t fixed_decimals,
                   char filler)
{
  /* {intg_len, frac_len} output widths; {intg, frac} places in input */
  int len, frac= from->frac, i, intg_len, frac_len, fill, intg;
  decimal_digits_t intg_tmp;
  /* number digits before decimal point */
  int fixed_intg= (fixed_precision ?
                   (fixed_precision - fixed_decimals) : 0);
  int error=E_DEC_OK;
  char *s=to;
  dec1 *buf, *buf0=from->buf, tmp;

  DBUG_ASSERT(*to_len >= 2+ (int) from->sign);

  /* removing leading zeroes */
  buf0= remove_leading_zeroes(from, &intg_tmp);
  intg= (int) intg_tmp;               /* intg can be negative later */
  if (unlikely(intg+frac==0))
  {
    intg=1;
    tmp=0;
    buf0=&tmp;
  }

  if (!(intg_len= fixed_precision ? fixed_intg : intg))
    intg_len= 1;
  frac_len= fixed_precision ? fixed_decimals : frac;
  len= from->sign + intg_len + MY_TEST(frac) + frac_len;
  if (fixed_precision)
  {
    if (frac > fixed_decimals)
    {
      error= E_DEC_TRUNCATED;
      frac= fixed_decimals;
    }
    if (intg > fixed_intg)
    {
      error= E_DEC_OVERFLOW;
      intg= fixed_intg;
    }
  }
  else if (unlikely(len > --*to_len)) /* reserve one byte for \0 */
  {
    int j= len-*to_len;
    error= (frac && j <= frac + 1) ? E_DEC_TRUNCATED : E_DEC_OVERFLOW;
    if (frac && j >= frac + 1) j--;
    if (j > frac)
    {
      intg-= j-frac;
      frac= 0;
    }
    else
      frac-=j;
    frac_len= frac;
    len= from->sign + intg_len + MY_TEST(frac) + frac_len;