Drizzled Public API Documentation

additive_op.cc
1 /* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
2  * vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
3  *
4  * Copyright (C) 2008 Sun Microsystems, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 #include <config.h>
21 
22 #include <drizzled/function/additive_op.h>
23 #include <drizzled/type/decimal.h>
24 
25 #include <algorithm>
26 
27 using namespace std;
28 
29 namespace drizzled
30 {
31 
35 void Item_func_additive_op::result_precision()
36 {
37  decimals= max(args[0]->decimals, args[1]->decimals);
38  int max_int_part= max(args[0]->decimal_precision() - args[0]->decimals,
39  args[1]->decimal_precision() - args[1]->decimals);
40  int precision= min(max_int_part + 1 + decimals, DECIMAL_MAX_PRECISION);
41 
42  /* Integer operations keep unsigned_flag if one of arguments is unsigned */
43  if (result_type() == INT_RESULT)
44  unsigned_flag= args[0]->unsigned_flag | args[1]->unsigned_flag;
45  else
46  unsigned_flag= args[0]->unsigned_flag & args[1]->unsigned_flag;
47 
48  max_length= class_decimal_precision_to_length(precision, decimals,
49  unsigned_flag);
50 }
51 
52 } /* namespace drizzled */