~drizzle-trunk/drizzle/development

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

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

 *

 *  Copyright (C) 2008-2009 Sun Microsystems

 *

 *  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

 */

/**

 * @file Implementation of CreateField class

 */

#include "config.h"

#include <errno.h>

#include <float.h>

#include "drizzled/sql_select.h"

#include "drizzled/error.h"

#include "drizzled/field.h"

#include "drizzled/create_field.h"

#include "drizzled/field/str.h"

#include "drizzled/field/num.h"

#include "drizzled/field/blob.h"

#include "drizzled/field/enum.h"

#include "drizzled/field/null.h"

#include "drizzled/field/date.h"

#include "drizzled/field/decimal.h"

#include "drizzled/field/real.h"

#include "drizzled/field/double.h"

#include "drizzled/field/long.h"

#include "drizzled/field/int64_t.h"

#include "drizzled/field/num.h"

#include "drizzled/field/timestamp.h"

#include "drizzled/field/datetime.h"

#include "drizzled/field/varstring.h"

#include "drizzled/temporal.h"

#include <algorithm>

using namespace std;

namespace drizzled

{

/** Create a field suitable for create of table. */

CreateField::CreateField(Field *old_field, Field *orig_field)

{

  field= old_field;

  field_name= change= old_field->field_name;

  length= old_field->field_length;

  flags= old_field->flags;

  unireg_check= old_field->unireg_check;

  pack_length= old_field->pack_length();

  key_length= old_field->key_length();

  sql_type= old_field->real_type();

  charset= old_field->charset(); // May be NULL ptr

  comment= old_field->comment;

  decimals= old_field->decimals();

  /* Fix if the original table had 4 byte pointer blobs */

  if (flags & BLOB_FLAG)

    pack_length= (pack_length - old_field->table->getShare()->blob_ptr_size + portable_sizeof_char_ptr);

  switch (sql_type) 

  {

    case DRIZZLE_TYPE_BLOB:

      sql_type= DRIZZLE_TYPE_BLOB;

      length/= charset->mbmaxlen;

      key_length/= charset->mbmaxlen;

      break;

    case DRIZZLE_TYPE_ENUM:

    case DRIZZLE_TYPE_VARCHAR:

      /* This is corrected in create_length_to_internal_length */

      length= (length+charset->mbmaxlen-1) / charset->mbmaxlen;

      break;

    default:

      break;

  }

  if (flags & ENUM_FLAG)

    interval= ((Field_enum*) old_field)->typelib;

  else

    interval= 0;

  def= 0;

  char_length= length;

  if (!(flags & (NO_DEFAULT_VALUE_FLAG )) &&

      old_field->ptr && orig_field &&

      (sql_type != DRIZZLE_TYPE_TIMESTAMP ||                /* set def only if */

       old_field->table->timestamp_field != old_field ||  /* timestamp field */

       unireg_check == Field::TIMESTAMP_UN_FIELD))        /* has default val */

  {

    ptrdiff_t diff;

    /* Get the value from default_values */

    diff= (ptrdiff_t) (orig_field->table->getDefaultValues() - orig_field->table->record[0]);

    orig_field->move_field_offset(diff);	// Points now at default_values

    if (! orig_field->is_real_null())

    {

      char buff[MAX_FIELD_WIDTH], *pos;

      String tmp(buff, sizeof(buff), charset), *res;

      res= orig_field->val_str(&tmp);

      pos= (char*) memory::sql_strmake(res->ptr(), res->length());

      def= new Item_string(pos, res->length(), charset);

    }

    orig_field->move_field_offset(-diff);	// Back to record[0]

  }

}

/**

  Convert CreateField::length from number of characters to number of bytes.

*/

void CreateField::create_length_to_internal_length(void)

{

  switch (sql_type) 

  {

    case DRIZZLE_TYPE_BLOB:

    case DRIZZLE_TYPE_VARCHAR:

      length*= charset->mbmaxlen;

      key_length= length;

      pack_length= calc_pack_length(sql_type, length);

      break;

    case DRIZZLE_TYPE_ENUM:

      /* Pack_length already calculated in ::init() */

      length*= charset->mbmaxlen;

      key_length= pack_length;

      break;

    case DRIZZLE_TYPE_DECIMAL:

      key_length= pack_length=

        my_decimal_get_binary_size(my_decimal_length_to_precision(length,

                  decimals,

                  flags &

                  UNSIGNED_FLAG),

          decimals);

      break;

    default:

      key_length= pack_length= calc_pack_length(sql_type, length);

      break;

  }

}

/**

  Init for a tmp table field. To be extended if need be.

*/

void CreateField::init_for_tmp_table(enum_field_types sql_type_arg,

                                     uint32_t length_arg,

                                     uint32_t decimals_arg,

                                     bool maybe_null)

{

  field_name= "";

  sql_type= sql_type_arg;

  char_length= length= length_arg;;

  unireg_check= Field::NONE;

  interval= 0;

  charset= &my_charset_bin;

  decimals= decimals_arg & FIELDFLAG_MAX_DEC;

  if (! maybe_null)

    flags= NOT_NULL_FLAG;

  else

    flags= 0;

}

bool CreateField::init(Session *,

                        char *fld_name,

                        enum_field_types fld_type,

                        char *fld_length,

                        char *fld_decimals,

                        uint32_t fld_type_modifier,

                        Item *fld_default_value,

                        Item *fld_on_update_value,

                        LEX_STRING *fld_comment,

                        char *fld_change,

                        List<String> *fld_interval_list,

                        const CHARSET_INFO * const fld_charset,

                        uint32_t,

                        enum column_format_type column_format_in)

{

  uint32_t sign_len= 0;

  uint32_t allowed_type_modifier= 0;

  uint32_t max_field_charlength= MAX_FIELD_CHARLENGTH;

  field= 0;

  field_name= fld_name;

  def= fld_default_value;

  flags= fld_type_modifier;

  flags|= (((uint32_t)column_format_in & COLUMN_FORMAT_MASK) << COLUMN_FORMAT_FLAGS);

  unireg_check= (fld_type_modifier & AUTO_INCREMENT_FLAG ?

                 Field::NEXT_NUMBER : Field::NONE);

  decimals= fld_decimals ? (uint32_t)atoi(fld_decimals) : 0;

  if (decimals >= NOT_FIXED_DEC)

  {

    my_error(ER_TOO_BIG_SCALE, MYF(0), decimals, fld_name,

             NOT_FIXED_DEC-1);

    return(true);

  }

  sql_type= fld_type;

  length= 0;

  change= fld_change;

  interval= 0;

  pack_length= key_length= 0;

  charset= fld_charset;

  interval_list.empty();

  comment= *fld_comment;

  /*

    Set NO_DEFAULT_VALUE_FLAG if this field doesn't have a default value and

    it is NOT NULL, not an AUTO_INCREMENT field and not a TIMESTAMP.

  */

  if (!fld_default_value && !(fld_type_modifier & AUTO_INCREMENT_FLAG) &&

      (fld_type_modifier & NOT_NULL_FLAG) && fld_type != DRIZZLE_TYPE_TIMESTAMP)

    flags|= NO_DEFAULT_VALUE_FLAG;

  if (fld_length && !(length= (uint32_t) atoi(fld_length)))

    fld_length= 0;

  sign_len= fld_type_modifier & UNSIGNED_FLAG ? 0 : 1;

  switch (fld_type) 

  {

    case DRIZZLE_TYPE_LONG:

      if (!fld_length)

        length= MAX_INT_WIDTH+sign_len;

      allowed_type_modifier= AUTO_INCREMENT_FLAG;

      break;

    case DRIZZLE_TYPE_LONGLONG:

      if (!fld_length)

        length= MAX_BIGINT_WIDTH;

      allowed_type_modifier= AUTO_INCREMENT_FLAG;

      break;

    case DRIZZLE_TYPE_NULL:

      break;

    case DRIZZLE_TYPE_DECIMAL:

      my_decimal_trim(&length, &decimals);

      if (length > DECIMAL_MAX_PRECISION)

      {

        my_error(ER_TOO_BIG_PRECISION, MYF(0), length, fld_name,

                DECIMAL_MAX_PRECISION);

        return(true);

      }

      if (length < decimals)

      {

        my_error(ER_M_BIGGER_THAN_D, MYF(0), fld_name);

        return(true);

      }

      length= my_decimal_precision_to_length(length, decimals, fld_type_modifier & UNSIGNED_FLAG);

      pack_length= my_decimal_get_binary_size(length, decimals);

      break;

    case DRIZZLE_TYPE_VARCHAR:

      /*

        Long VARCHAR's are automaticly converted to blobs in mysql_prepare_table

        if they don't have a default value

      */

      max_field_charlength= MAX_FIELD_VARCHARLENGTH;

      break;

    case DRIZZLE_TYPE_BLOB:

      if (fld_default_value)

      {

        /* Allow empty as default value. */

        String str,*res;

        res= fld_default_value->val_str(&str);

        if (res->length())

        {

          my_error(ER_BLOB_CANT_HAVE_DEFAULT, MYF(0), fld_name);

          return(true);

        }

      }

      flags|= BLOB_FLAG;

      break;

    case DRIZZLE_TYPE_DOUBLE:

      allowed_type_modifier= AUTO_INCREMENT_FLAG;

      if (!fld_length && !fld_decimals)

      {

        length= DBL_DIG+7;

        decimals= NOT_FIXED_DEC;

      }

      if (length < decimals &&

          decimals != NOT_FIXED_DEC)

      {

        my_error(ER_M_BIGGER_THAN_D, MYF(0), fld_name);

        return(true);

      }

      break;

    case DRIZZLE_TYPE_TIMESTAMP:

      if (!fld_length)

      {

        length= DateTime::MAX_STRING_LENGTH;

      }

      /* This assert() should be correct due to absence of length

         specifiers for timestamp. Previous manipulation also wasn't

         ever called (from examining lcov)

      */

      assert(length == (uint32_t)DateTime::MAX_STRING_LENGTH);

      flags|= UNSIGNED_FLAG;

      if (fld_default_value)

      {

        /* Grammar allows only NOW() value for ON UPDATE clause */

        if (fld_default_value->type() == Item::FUNC_ITEM &&

            ((Item_func*)fld_default_value)->functype() == Item_func::NOW_FUNC)

        {

          unireg_check= (fld_on_update_value ? Field::TIMESTAMP_DNUN_FIELD:

                                              Field::TIMESTAMP_DN_FIELD);

          /*

            We don't need default value any longer moreover it is dangerous.

            Everything handled by unireg_check further.

          */

          def= 0;

        }

        else

          unireg_check= (fld_on_update_value ? Field::TIMESTAMP_UN_FIELD:

                                              Field::NONE);

      }

      else

      {

        /*

          If we have default TIMESTAMP NOT NULL column without explicit DEFAULT

          or ON UPDATE values then for the sake of compatiblity we should treat

          this column as having DEFAULT NOW() ON UPDATE NOW() (when we don't

          have another TIMESTAMP column with auto-set option before this one)

          or DEFAULT 0 (in other cases).

          So here we are setting TIMESTAMP_OLD_FIELD only temporary, and will

          replace this value by TIMESTAMP_DNUN_FIELD or NONE later when

          information about all TIMESTAMP fields in table will be availiable.

          If we have TIMESTAMP NULL column without explicit DEFAULT value

          we treat it as having DEFAULT NULL attribute.

        */

        unireg_check= (fld_on_update_value ? Field::TIMESTAMP_UN_FIELD :

                      (flags & NOT_NULL_FLAG ? Field::TIMESTAMP_OLD_FIELD :

                                                Field::NONE));

      }

      break;

    case DRIZZLE_TYPE_DATE:

      length= Date::MAX_STRING_LENGTH;

      break;

    case DRIZZLE_TYPE_DATETIME:

      length= DateTime::MAX_STRING_LENGTH;

      break;

    case DRIZZLE_TYPE_ENUM:

      {

        /* Should be safe. */

        pack_length= get_enum_pack_length(fld_interval_list->elements);

        List_iterator<String> it(*fld_interval_list);

        String *tmp;

        while ((tmp= it++))

          interval_list.push_back(tmp);

        length= 1;

        break;

    }

  }

  /* Remember the value of length */

  char_length= length;

  if (!(flags & BLOB_FLAG) &&

      ((length > max_field_charlength &&

        fld_type != DRIZZLE_TYPE_ENUM &&

        (fld_type != DRIZZLE_TYPE_VARCHAR || fld_default_value)) ||

       (!length && fld_type != DRIZZLE_TYPE_VARCHAR)))

  {

    my_error((fld_type == DRIZZLE_TYPE_VARCHAR) ?  ER_TOO_BIG_FIELDLENGTH : ER_TOO_BIG_DISPLAYWIDTH,

              MYF(0),

              fld_name, max_field_charlength);

    return true;

  }

  fld_type_modifier&= AUTO_INCREMENT_FLAG;

  if ((~allowed_type_modifier) & fld_type_modifier)

  {

    my_error(ER_WRONG_FIELD_SPEC, MYF(0), fld_name);

    return true;

  }

  return false; /* success */

}

} /* namespace drizzled */