~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/locate.h>

namespace drizzled

{

void Item_func_locate::fix_length_and_dec()

{

  max_length= MY_INT32_NUM_DECIMAL_DIGITS;

  agg_arg_charsets(cmp_collation, args, 2, MY_COLL_CMP_CONV, 1);

}

int64_t Item_func_locate::val_int()

{

  assert(fixed == 1);

  String *a=args[0]->val_str(&value1);

  String *b=args[1]->val_str(&value2);

  if (!a || !b)

  {

    null_value=1;

    return 0;

  }

  null_value=0;

  /* must be int64_t to avoid truncation */

  int64_t start=  0;

  int64_t start0= 0;

  my_match_t match;

  if (arg_count == 3)

  {

    start0= start= args[2]->val_int() - 1;

    if ((start < 0) || (start > static_cast<int64_t>(a->length())))

      return 0;

    /* start is now sufficiently valid to pass to charpos function */

    start= a->charpos((int) start);

    if (start + b->length() > a->length())

      return 0;

  }

  if (!b->length())                             // Found empty string at start

    return start + 1;

  if (!cmp_collation.collation->coll->instr(cmp_collation.collation,

                                            a->ptr()+start,

                                            (uint32_t) (a->length()-start),

                                            b->ptr(), b->length(),

                                            &match, 1))

    return 0;

  return (int64_t) match.mb_len + start0 + 1;

}

void Item_func_locate::print(String *str, enum_query_type query_type)

{

  str->append(STRING_WITH_LEN("locate("));

  args[1]->print(str, query_type);

  str->append(',');

  args[0]->print(str, query_type);

  if (arg_count == 3)

  {

    str->append(',');

    args[2]->print(str, query_type);

  }

  str->append(')');

}

} /* namespace drizzled */