~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

 */

#pragma once

#include <drizzled/function/func.h>

#include <drizzled/lex_string.h>

namespace drizzled

{

class sys_var;

Item *get_system_var(Session *session, sql_var_t var_type, LEX_STRING name,

                     LEX_STRING component);

/* A system variable */

class Item_func_get_system_var :public Item_func

{

  sys_var *var;

  sql_var_t var_type;

  LEX_STRING component;

public:

  Item_func_get_system_var(sys_var *var_arg, sql_var_t var_type_arg,

                           LEX_STRING *component_arg, const char *name_arg,

                           size_t name_len_arg);

  bool fix_fields(Session *session, Item **ref);

  /*

    Stubs for pure virtual methods. Should never be called: this

    item is always substituted with a constant in fix_fields().

  */

  double val_real()         { assert(0); return 0.0; }

  int64_t val_int()        { assert(0); return 0; }

  String* val_str(String*)  { assert(0); return 0; }

  void fix_length_and_dec() { assert(0); }

  /* TODO: fix to support views */

  const char *func_name() const { return "get_system_var"; }

};

} /* namespace drizzled */