Commit e4cdb193 authored by unknown's avatar unknown
Browse files

Fix for bug #10337 (cast(NULL DECIMAL) crashes the server) 


mysql-test/r/cast.result:
  test result fixed
mysql-test/t/cast.test:
  test case added
sql/item_func.cc:
  checks for NULL added
strings/decimal.c:
  we need to return specified 'scale' for the rounded decimal
parent b0df4494

mysql-test/r/cast.result

+3 −0
Original line number Diff line number Diff line
@@ -344,3 +344,6 @@ select cast(s1 as decimal(7,2)) from t1; 
cast(s1 as decimal(7,2))

111111.00

drop table t1;

select cast(NULL as decimal(6)) as t1;

t1

NULL

mysql-test/t/cast.test

+6 −0
Original line number Diff line number Diff line
@@ -168,3 +168,9 @@ create table t1(s1 time); 
insert into t1 values ('11:11:11');

select cast(s1 as decimal(7,2)) from t1;

drop table t1;



#

# Bug @10237 (CAST(NULL DECIMAL) crashes server)

#

select cast(NULL as decimal(6)) as t1;

sql/item_func.cc

+8 −1
Original line number Diff line number Diff line
@@ -1022,7 +1022,8 @@ longlong Item_func_unsigned::val_int() 
String *Item_decimal_typecast::val_str(String *str)

{

  my_decimal tmp_buf, *tmp= val_decimal(&tmp_buf);

  my_decimal_round(E_DEC_FATAL_ERROR, tmp, decimals, FALSE, &tmp_buf);

  if (null_value)

    return NULL;

  my_decimal2string(E_DEC_FATAL_ERROR, &tmp_buf, 0, 0, 0, str);

  return str;

}
@@ -1032,6 +1033,8 @@ double Item_decimal_typecast::val_real() 
{

  my_decimal tmp_buf, *tmp= val_decimal(&tmp_buf);

  double res;

  if (null_value)

    return 0.0;

  my_decimal2double(E_DEC_FATAL_ERROR, tmp, &res);

  return res;

}
@@ -1041,6 +1044,8 @@ longlong Item_decimal_typecast::val_int() 
{

  my_decimal tmp_buf, *tmp= val_decimal(&tmp_buf);

  longlong res;

  if (null_value)

    return 0;

  my_decimal2int(E_DEC_FATAL_ERROR, tmp, unsigned_flag, &res);

  return res;

}
@@ -1049,6 +1054,8 @@ longlong Item_decimal_typecast::val_int() 
my_decimal *Item_decimal_typecast::val_decimal(my_decimal *dec)

{

  my_decimal tmp_buf, *tmp= args[0]->val_decimal(&tmp_buf);

  if ((null_value= args[0]->null_value))

    return NULL;

  my_decimal_round(E_DEC_FATAL_ERROR, tmp, decimals, FALSE, dec);

  return dec;

}

strings/decimal.c

+7 −1
Original line number Diff line number Diff line
@@ -1563,7 +1563,13 @@ decimal_round(decimal_t *from, decimal_t *to, int scale, 
        break;

      if (buf1-- == to->buf)

      {

        decimal_make_zero(to);

        /* making 'zero' with the proper scale */

        dec1 *p0= to->buf + frac0 + 1;

        to->intg=1;

        to->frac= max(scale, 0);

        to->sign= 0;

        for (buf1= to->buf; buf1<p0; buf1++)

          *buf1= 0;

        return E_DEC_OK;

      }

    }