~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2008 Sun Microsystems, Inc.

 *

 *  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 "config.h"

#include <drizzled/function/math/neg.h>

namespace drizzled

{

double Item_func_neg::real_op()

{

  double value= args[0]->val_real();

  null_value= args[0]->null_value;

  return -value;

}

int64_t Item_func_neg::int_op()

{

  int64_t value= args[0]->val_int();

  null_value= args[0]->null_value;

  return -value;

}

type::Decimal *Item_func_neg::decimal_op(type::Decimal *decimal_value)

{

  type::Decimal val, *value= args[0]->val_decimal(&val);

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

  {

    class_decimal2decimal(value, decimal_value);

    class_decimal_neg(decimal_value);

    return decimal_value;

  }

  return 0;

}

void Item_func_neg::fix_num_length_and_dec()

{

  decimals= args[0]->decimals;

  /* 1 add because sign can appear */

  max_length= args[0]->max_length + 1;

}

void Item_func_neg::fix_length_and_dec()

{

  Item_func_num1::fix_length_and_dec();

  /*

    If this is in integer context keep the context as integer if possible

    (This is how multiplication and other integer functions works)

    Use val() to get value as arg_type doesn't mean that item is

    Item_int or Item_real due to existence of Item_param.

  */

  if (hybrid_type == INT_RESULT && args[0]->const_item())

  {

    int64_t val= args[0]->val_int();

    if ((uint64_t) val >= (uint64_t) INT64_MIN &&

        ((uint64_t) val != (uint64_t) INT64_MIN ||

          args[0]->type() != INT_ITEM))

    {

      /*

        Ensure that result is converted to DECIMAL, as int64_t can't hold

        the negated number

      */

      hybrid_type= DECIMAL_RESULT;

    }

  }

  unsigned_flag= false;

}

} /* namespace drizzled */