Function natsort_encode_numeric_string

sql/item_strfunc.cc:5716–5730

Encode numeric string for natural sorting. @param[in] in - start of the numeric string skipping leading zeros @param[in] n_digits - length of the string, in characters, not counting leading zeros. @param[out] out - String to write to. The string should have enough preallocated space to fit the encoded key. @return NATSORT_ERR::SUCCESS - success NATSORT_ERR::KEY_

   CONCAT(natsort_encode_length(n_digits), in)
*/
static NATSORT_ERR natsort_encode_numeric_string(const char *in,
                                                 size_t n_digits,
                                                 String *out)
{
  DBUG_ASSERT(in);
  DBUG_ASSERT(n_digits);

  if (out->length() + natsort_encode_length_max(n_digits - 1) + n_digits >
      out->alloced_length())
    return NATSORT_ERR::KEY_TOO_LARGE;

  natsort_encode_length(n_digits - 1, out);
  out->append(in, n_digits);
  return NATSORT_ERR::SUCCESS;
}

/*
  Calculate max size of the natsort key.