string.h

/* -*- 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
 */

#pragma once

#include <drizzled/item/basic_constant.h>
#include <drizzled/charset.h>

namespace drizzled {

class Item_string : public Item_basic_constant
{
public:
  Item_string(str_ref str, const charset_info_st* cs, Derivation dv= DERIVATION_COERCIBLE)
  {
    assert(not (str.size() % cs->mbminlen));
    str_value.set(str.data(), str.size(), cs);
    collation.set(cs, dv);
    /*
      We have to have a different max_length than 'length' here to
      ensure that we get the right length if we do use the item
      to create a new table. In this case max_length must be the maximum
      number of chars for a string of this type because we in CreateField::
      divide the max_length with mbmaxlen).
    */
    max_length= str_value.numchars() * cs->mbmaxlen;
    set_name(str.data(), str.size(), cs);
    decimals=NOT_FIXED_DEC;
    // it is constant => can be used without fix_fields (and frequently used)
    fixed= 1;
  }

  Item_string(const char *str,uint32_t length,
              const charset_info_st * const cs, Derivation dv= DERIVATION_COERCIBLE)
  {
    assert(not (length % cs->mbminlen));
    str_value.set(str, length, cs);
    collation.set(cs, dv);
    /*
      We have to have a different max_length than 'length' here to
      ensure that we get the right length if we do use the item
      to create a new table. In this case max_length must be the maximum
      number of chars for a string of this type because we in CreateField::
      divide the max_length with mbmaxlen).
    */
    max_length= str_value.numchars()*cs->mbmaxlen;
    set_name(str, length, cs);
    decimals=NOT_FIXED_DEC;
    // it is constant => can be used without fix_fields (and frequently used)
    fixed= 1;
  }
  /* Just create an item and do not fill string representation */
  Item_string(const charset_info_st * const cs, Derivation dv= DERIVATION_COERCIBLE)
  {
    collation.set(cs, dv);
    max_length= 0;
    set_name(NULL, 0, cs);
    decimals= NOT_FIXED_DEC;
    fixed= 1;
  }
  Item_string(const char *name_par, const char *str, uint32_t length,
              const charset_info_st * const cs, Derivation dv= DERIVATION_COERCIBLE)
  {
    assert(not (length % cs->mbminlen));
    str_value.set(str, length, cs);
    collation.set(cs, dv);
    max_length= str_value.numchars()*cs->mbmaxlen;
    set_name(name_par, 0, cs);
    decimals=NOT_FIXED_DEC;
    // it is constant => can be used without fix_fields (and frequently used)
    fixed= 1;
  }
  enum Type type() const { return STRING_ITEM; }
  double val_real();
  int64_t val_int();
  String *val_str(String*)
  {
    assert(fixed == 1);
    return (String*) &str_value;
  }
  type::Decimal *val_decimal(type::Decimal *);
  int save_in_field(Field *field, bool no_conversions);
  enum Item_result result_type () const { return STRING_RESULT; }
  enum_field_types field_type() const { return DRIZZLE_TYPE_VARCHAR; }
  bool basic_const_item() const { return 1; }
  bool eq(const Item *item, bool binary_cmp) const;
  Item *clone_item()
  {
    return new Item_string(name, str_value.ptr(), str_value.length(), collation.collation);
  }
  Item *safe_charset_converter(const charset_info_st * const tocs);
  inline void append(str_ref v)
  {
    str_value.append(v);
    max_length= str_value.numchars() * collation.collation->mbmaxlen;
  }
  virtual void print(String *str);
};


class Item_static_string_func : public Item_string
{
  const char *func_name;
public:
  Item_static_string_func(const char *name_par, str_ref str, const charset_info_st* cs, Derivation dv= DERIVATION_COERCIBLE) :
    Item_string(NULL, str.data(), str.size(), cs, dv), func_name(name_par)
  {}
  Item *safe_charset_converter(const charset_info_st*);

  virtual inline void print(String *str)
  {
    str->append(func_name);
  }
};

} /* namespace drizzled */