mi_create.c

/*
   Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.

   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 */

/* Create a MyISAM table */

#include "ftdefs.h"
#include "sp_defs.h"
#include <my_bit.h>

#ifdef __WIN__
#include <fcntl.h>
#endif
#include <m_ctype.h>

/*
  Old options is used when recreating database, from myisamchk
*/

int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
              uint columns, MI_COLUMNDEF *recinfo,
              uint uniques, MI_UNIQUEDEF *uniquedefs,
              MI_CREATE_INFO *ci,uint flags)
{
  register uint i,j;
  File UNINIT_VAR(dfile), UNINIT_VAR(file);
  int errpos,save_errno, create_mode= O_RDWR | O_TRUNC;
  myf create_flag;
  uint fields,length,max_key_length,packed,pointer,real_length_diff,
       key_length,info_length,key_segs,options,min_key_length_skip,
       base_pos,long_varchar_count,varchar_length,
       max_key_block_length,unique_key_parts,fulltext_keys,offset;
  uint aligned_key_start, block_length;
  uint internal_table= flags & HA_CREATE_INTERNAL_TABLE;
  ulong reclength, real_reclength,min_pack_length;
  char filename[FN_REFLEN],linkname[FN_REFLEN], *linkname_ptr;
  ulong pack_reclength;
  ulonglong tot_length,max_rows, tmp;
  enum en_fieldtype type;
  MYISAM_SHARE share;
  MI_KEYDEF *keydef,tmp_keydef;
  MI_UNIQUEDEF *uniquedef;
  HA_KEYSEG *keyseg,tmp_keyseg;
  MI_COLUMNDEF *rec;
  ulong *rec_per_key_part;
  my_off_t key_root[HA_MAX_POSSIBLE_KEY],key_del[MI_MAX_KEY_BLOCK_SIZE];
  MI_CREATE_INFO tmp_create_info;
  DBUG_ENTER("mi_create");
  DBUG_PRINT("enter", ("keys: %u  columns: %u  uniques: %u  flags: %u",
                      keys, columns, uniques, flags));

  if (!ci)
  {
    memset(&tmp_create_info, 0, sizeof(tmp_create_info));
    ci=&tmp_create_info;
  }

  if (keys + uniques > MI_MAX_KEY || columns == 0)
  {
    DBUG_RETURN(my_errno=HA_WRONG_CREATE_OPTION);
  }

  errpos=0;
  options=0;
  memset(&share, 0, sizeof(share));

  if (flags & HA_DONT_TOUCH_DATA)
  {
    if (!(ci->old_options & HA_OPTION_TEMP_COMPRESS_RECORD))
      options=ci->old_options &
        (HA_OPTION_COMPRESS_RECORD | HA_OPTION_PACK_RECORD |
         HA_OPTION_READ_ONLY_DATA | HA_OPTION_CHECKSUM |
         HA_OPTION_TMP_TABLE | HA_OPTION_DELAY_KEY_WRITE);
    else
      options=ci->old_options &
        (HA_OPTION_CHECKSUM | HA_OPTION_TMP_TABLE | HA_OPTION_DELAY_KEY_WRITE);
  }

  if (ci->reloc_rows > ci->max_rows)
    ci->reloc_rows=ci->max_rows;                /* Check if wrong parameter */

  if (!(rec_per_key_part=
        (ulong*) my_malloc((keys + uniques)*MI_MAX_KEY_SEG*sizeof(long),
                           MYF(MY_WME | MY_ZEROFILL))))
    DBUG_RETURN(my_errno);

        /* Start by checking fields and field-types used */

  reclength=varchar_length=long_varchar_count=packed=
    min_pack_length=pack_reclength=0;
  for (rec=recinfo, fields=0 ;
       fields != columns ;
       rec++,fields++)
  {
    reclength+=rec->length;
    if ((type=(enum en_fieldtype) rec->type) != FIELD_NORMAL &&
        type != FIELD_CHECK)
    {
      packed++;
      if (type == FIELD_BLOB)
      {
        share.base.blobs++;
        if (pack_reclength != INT_MAX32)
        {
          if (rec->length == 4+portable_sizeof_char_ptr)
            pack_reclength= INT_MAX32;
          else
            pack_reclength+=(1 << ((rec->length-portable_sizeof_char_ptr)*8)); /* Max blob length */
        }
      }
      else if (type == FIELD_SKIP_PRESPACE ||
               type == FIELD_SKIP_ENDSPACE)
      {
        if (pack_reclength != INT_MAX32)
          pack_reclength+= rec->length > 255 ? 2 : 1;
        min_pack_length++;
      }
      else if (type == FIELD_VARCHAR)
      {
        varchar_length+= rec->length-1;          /* Used for min_pack_length */
        packed--;
        pack_reclength++;
        min_pack_length++;
        /* We must test for 257 as length includes pack-length */
        if (test(rec->length >= 257))
        {
          long_varchar_count++;
          pack_reclength+= 2;                   /* May be packed on 3 bytes */
        }
      }
      else if (type != FIELD_SKIP_ZERO)
      {
        min_pack_length+=rec->length;
        packed--;                               /* Not a pack record type */
      }
    }
    else                                        /* FIELD_NORMAL */
      min_pack_length+=rec->length;
  }
  if ((packed & 7) == 1)
  {                             /* Bad packing, try to remove a zero-field */
    while (rec != recinfo)
    {
      rec--;
      if (rec->type == (int) FIELD_SKIP_ZERO && rec->length == 1)
      {
        /*
          NOTE1: here we change a field type FIELD_SKIP_ZERO ->
          FIELD_NORMAL
        */
        rec->type=(int) FIELD_NORMAL;
        packed--;
        min_pack_length++;
        break;
      }
    }
  }

  if (packed || (flags & HA_PACK_RECORD))
    options|=HA_OPTION_PACK_RECORD;     /* Must use packed records */
  /* We can't use checksum with static length rows */
  if (!(options & HA_OPTION_PACK_RECORD))
    options&= ~HA_OPTION_CHECKSUM;
  if (!(options & (HA_OPTION_PACK_RECORD | HA_OPTION_COMPRESS_RECORD)))
    min_pack_length+= varchar_length;
  if (flags & HA_CREATE_TMP_TABLE)
  {
    options|= HA_OPTION_TMP_TABLE;
    create_mode|= O_EXCL | O_NOFOLLOW;
  }
  if (flags & HA_CREATE_CHECKSUM || (options & HA_OPTION_CHECKSUM))
  {
    options|= HA_OPTION_CHECKSUM;
    min_pack_length++;
  }
  if (flags & HA_CREATE_DELAY_KEY_WRITE)
    options|= HA_OPTION_DELAY_KEY_WRITE;
  if (flags & HA_CREATE_RELIES_ON_SQL_LAYER)
    options|= HA_OPTION_RELIES_ON_SQL_LAYER;

  packed=(packed+7)/8;
  if (pack_reclength != INT_MAX32)
    pack_reclength+= reclength+packed +
      test(test_all_bits(options, HA_OPTION_CHECKSUM | HA_OPTION_PACK_RECORD));
  min_pack_length+=packed;

  if (!ci->data_file_length && ci->max_rows)
  {
    if (pack_reclength == INT_MAX32 ||
             (~(ulonglong) 0)/ci->max_rows < (ulonglong) pack_reclength)
      ci->data_file_length= ~(ulonglong) 0;
    else
      ci->data_file_length=(ulonglong) ci->max_rows*pack_reclength;
  }
  else if (!ci->max_rows)
    ci->max_rows=(ha_rows) (ci->data_file_length/(min_pack_length +
                                         ((options & HA_OPTION_PACK_RECORD) ?
                                          3 : 0)));

  if (options & (HA_OPTION_COMPRESS_RECORD | HA_OPTION_PACK_RECORD))
    pointer=mi_get_pointer_length(ci->data_file_length,myisam_data_pointer_size);
  else
    pointer=mi_get_pointer_length(ci->max_rows,myisam_data_pointer_size);
  if (!(max_rows=(ulonglong) ci->max_rows))
    max_rows= ((((ulonglong) 1 << (pointer*8)) -1) / min_pack_length);


  real_reclength=reclength;
  if (!(options & (HA_OPTION_COMPRESS_RECORD | HA_OPTION_PACK_RECORD)))
  {
    if (reclength <= pointer)
      reclength=pointer+1;              /* reserve place for delete link */
  }
  else
    reclength+= long_varchar_count;     /* We need space for varchar! */

  max_key_length=0; tot_length=0 ; key_segs=0;
  fulltext_keys=0;
  max_key_block_length=0;
  share.state.rec_per_key_part=rec_per_key_part;
  share.state.key_root=key_root;
  share.state.key_del=key_del;
  if (uniques)
  {
    max_key_block_length= myisam_block_size;
    max_key_length=       MI_UNIQUE_HASH_LENGTH + pointer;
  }

  for (i=0, keydef=keydefs ; i < keys ; i++ , keydef++)
  {

    share.state.key_root[i]= HA_OFFSET_ERROR;
    min_key_length_skip=length=real_length_diff=0;
    key_length=pointer;
    if (keydef->flag & HA_SPATIAL)
    {
#ifdef HAVE_SPATIAL
      /* BAR TODO to support 3D and more dimensions in the future */
      uint sp_segs=SPDIMS*2;
      keydef->flag=HA_SPATIAL;

      if (flags & HA_DONT_TOUCH_DATA)
      {
        /*
           called by myisamchk - i.e. table structure was taken from
           MYI file and SPATIAL key *does have* additional sp_segs keysegs.
           keydef->seg here points right at the GEOMETRY segment,
           so we only need to decrease keydef->keysegs.
           (see recreate_table() in mi_check.c)
        */
        keydef->keysegs-=sp_segs-1;
      }

      for (j=0, keyseg=keydef->seg ; (int) j < keydef->keysegs ;
           j++, keyseg++)
      {
        if (keyseg->type != HA_KEYTYPE_BINARY &&
            keyseg->type != HA_KEYTYPE_VARBINARY1 &&
            keyseg->type != HA_KEYTYPE_VARBINARY2)
        {
          my_errno=HA_WRONG_CREATE_OPTION;
          goto err_no_lock;
        }
      }
      keydef->keysegs+=sp_segs;
      key_length+=SPLEN*sp_segs;
      length++;                              /* At least one length byte */
      min_key_length_skip+=SPLEN*2*SPDIMS;
#else
      my_errno= HA_ERR_UNSUPPORTED;
      goto err_no_lock;
#endif /*HAVE_SPATIAL*/
    }
    else if (keydef->flag & HA_FULLTEXT)
    {
      keydef->flag=HA_FULLTEXT | HA_PACK_KEY | HA_VAR_LENGTH_KEY;
      options|=HA_OPTION_PACK_KEYS;             /* Using packed keys */

      for (j=0, keyseg=keydef->seg ; (int) j < keydef->keysegs ;
           j++, keyseg++)
      {
        if (keyseg->type != HA_KEYTYPE_TEXT &&
            keyseg->type != HA_KEYTYPE_VARTEXT1 &&
            keyseg->type != HA_KEYTYPE_VARTEXT2)
        {
          my_errno=HA_WRONG_CREATE_OPTION;
          goto err_no_lock;
        }
        if (!(keyseg->flag & HA_BLOB_PART) &&
            (keyseg->type == HA_KEYTYPE_VARTEXT1 ||
             keyseg->type == HA_KEYTYPE_VARTEXT2))
        {
          /* Make a flag that this is a VARCHAR */
          keyseg->flag|= HA_VAR_LENGTH_PART;
          /* Store in bit_start number of bytes used to pack the length */
          keyseg->bit_start= ((keyseg->type == HA_KEYTYPE_VARTEXT1)?
                              1 : 2);
        }
      }

      fulltext_keys++;
      key_length+= HA_FT_MAXBYTELEN+HA_FT_WLEN;
      length++;                              /* At least one length byte */
      min_key_length_skip+=HA_FT_MAXBYTELEN;
      real_length_diff=HA_FT_MAXBYTELEN-FT_MAX_WORD_LEN_FOR_SORT;
    }
    else
    {
      /* Test if prefix compression */
      if (keydef->flag & HA_PACK_KEY)
      {
        /* Can't use space_compression on number keys */
        if ((keydef->seg[0].flag & HA_SPACE_PACK) &&
            keydef->seg[0].type == (int) HA_KEYTYPE_NUM)
          keydef->seg[0].flag&= ~HA_SPACE_PACK;

        /* Only use HA_PACK_KEY when first segment is a variable length key */
        if (!(keydef->seg[0].flag & (HA_SPACE_PACK | HA_BLOB_PART |
                                     HA_VAR_LENGTH_PART)))
        {
          /* pack relative to previous key */
          keydef->flag&= ~HA_PACK_KEY;
          keydef->flag|= HA_BINARY_PACK_KEY | HA_VAR_LENGTH_KEY;
        }
        else
        {
          keydef->seg[0].flag|=HA_PACK_KEY;     /* for easyer intern test */
          keydef->flag|=HA_VAR_LENGTH_KEY;
          options|=HA_OPTION_PACK_KEYS;         /* Using packed keys */
        }
      }
      if (keydef->flag & HA_BINARY_PACK_KEY)
        options|=HA_OPTION_PACK_KEYS;           /* Using packed keys */

      if (keydef->flag & HA_AUTO_KEY && ci->with_auto_increment)
        share.base.auto_key=i+1;
      for (j=0, keyseg=keydef->seg ; j < keydef->keysegs ; j++, keyseg++)
      {
        /* numbers are stored with high by first to make compression easier */
        switch (keyseg->type) {
        case HA_KEYTYPE_SHORT_INT:
        case HA_KEYTYPE_LONG_INT:
        case HA_KEYTYPE_FLOAT:
        case HA_KEYTYPE_DOUBLE:
        case HA_KEYTYPE_USHORT_INT:
        case HA_KEYTYPE_ULONG_INT:
        case HA_KEYTYPE_LONGLONG:
        case HA_KEYTYPE_ULONGLONG:
        case HA_KEYTYPE_INT24:
        case HA_KEYTYPE_UINT24:
        case HA_KEYTYPE_INT8:
          keyseg->flag|= HA_SWAP_KEY;
          break;
        case HA_KEYTYPE_VARTEXT1:
        case HA_KEYTYPE_VARTEXT2:
        case HA_KEYTYPE_VARBINARY1:
        case HA_KEYTYPE_VARBINARY2:
          if (!(keyseg->flag & HA_BLOB_PART))
          {
            /* Make a flag that this is a VARCHAR */
            keyseg->flag|= HA_VAR_LENGTH_PART;
            /* Store in bit_start number of bytes used to pack the length */
            keyseg->bit_start= ((keyseg->type == HA_KEYTYPE_VARTEXT1 ||
                                 keyseg->type == HA_KEYTYPE_VARBINARY1) ?
                                1 : 2);
          }
          break;
        default:
          break;
        }
        if (keyseg->flag & HA_SPACE_PACK)
        {
          DBUG_ASSERT(!(keyseg->flag & HA_VAR_LENGTH_PART));
          keydef->flag |= HA_SPACE_PACK_USED | HA_VAR_LENGTH_KEY;
          options|=HA_OPTION_PACK_KEYS;         /* Using packed keys */
          length++;                             /* At least one length byte */
          min_key_length_skip+=keyseg->length;
          if (keyseg->length >= 255)
          {                                     /* prefix may be 3 bytes */
            min_key_length_skip+=2;
            length+=2;
          }
        }
        if (keyseg->flag & (HA_VAR_LENGTH_PART | HA_BLOB_PART))
        {
          DBUG_ASSERT(!test_all_bits(keyseg->flag,
                                    (HA_VAR_LENGTH_PART | HA_BLOB_PART)));
          keydef->flag|=HA_VAR_LENGTH_KEY;
          length++;                             /* At least one length byte */
          options|=HA_OPTION_PACK_KEYS;         /* Using packed keys */
          min_key_length_skip+=keyseg->length;
          if (keyseg->length >= 255)
          {                                     /* prefix may be 3 bytes */
            min_key_length_skip+=2;
            length+=2;
          }
        }
        key_length+= keyseg->length;
        if (keyseg->null_bit)
        {
          key_length++;
          options|=HA_OPTION_PACK_KEYS;
          keyseg->flag|=HA_NULL_PART;
          keydef->flag|=HA_VAR_LENGTH_KEY | HA_NULL_PART_KEY;
        }
      }
    } /* if HA_FULLTEXT */
    key_segs+=keydef->keysegs;
    if (keydef->keysegs > MI_MAX_KEY_SEG)
    {
      my_errno=HA_WRONG_CREATE_OPTION;
      goto err_no_lock;
    }
    /*
      key_segs may be 0 in the case when we only want to be able to
      add on row into the table. This can happen with some DISTINCT queries
      in MySQL
    */
    if ((keydef->flag & (HA_NOSAME | HA_NULL_PART_KEY)) == HA_NOSAME &&
        key_segs)
      share.state.rec_per_key_part[key_segs-1]=1L;
    length+=key_length;
    /* Get block length for key, if defined by user */
    block_length= (keydef->block_length ? 
                   my_round_up_to_next_power(keydef->block_length) :
                   myisam_block_size);
    block_length= MY_MAX(block_length, MI_MIN_KEY_BLOCK_LENGTH);
    block_length= MY_MIN(block_length, MI_MAX_KEY_BLOCK_LENGTH);

    keydef->block_length= (uint16) MI_BLOCK_SIZE(length-real_length_diff,
                                                 pointer,MI_MAX_KEYPTR_SIZE,
                                                 block_length);
    if (keydef->block_length > MI_MAX_KEY_BLOCK_LENGTH ||
        length >= MI_MAX_KEY_BUFF)
    {
      my_errno=HA_WRONG_CREATE_OPTION;
      goto err_no_lock;
    }
    set_if_bigger(max_key_block_length,keydef->block_length);
    keydef->keylength= (uint16) key_length;
    keydef->minlength= (uint16) (length-min_key_length_skip);
    keydef->maxlength= (uint16) length;

    if (length > max_key_length)
      max_key_length= length;
    tot_length+= (max_rows/(ulong) (((uint) keydef->block_length-5)/
                                    (length*2)))*
      (ulong) keydef->block_length;
  }
  for (i=max_key_block_length/MI_MIN_KEY_BLOCK_LENGTH ; i-- ; )
    key_del[i]=HA_OFFSET_ERROR;

  unique_key_parts=0;
  for (i=0, uniquedef=uniquedefs ; i < uniques ; i++ , uniquedef++)
  {
    uniquedef->key=keys+i;
    unique_key_parts+=uniquedef->keysegs;
    share.state.key_root[keys+i]= HA_OFFSET_ERROR;
    tot_length+= (max_rows/(ulong) (((uint) myisam_block_size-5)/
                         ((MI_UNIQUE_HASH_LENGTH + pointer)*2)))*
                         (ulong) myisam_block_size;
  }
  keys+=uniques;                                /* Each unique has 1 key */
  key_segs+=uniques;                            /* Each unique has 1 key seg */

  base_pos=(MI_STATE_INFO_SIZE + keys * MI_STATE_KEY_SIZE +
            max_key_block_length/MI_MIN_KEY_BLOCK_LENGTH*
            MI_STATE_KEYBLOCK_SIZE+
            key_segs*MI_STATE_KEYSEG_SIZE);
  info_length=base_pos+(uint) (MI_BASE_INFO_SIZE+
                               keys * MI_KEYDEF_SIZE+
                               uniques * MI_UNIQUEDEF_SIZE +
                               (key_segs + unique_key_parts)*HA_KEYSEG_SIZE+
                               columns*MI_COLUMNDEF_SIZE);
  DBUG_PRINT("info", ("info_length: %u", info_length));
  /* There are only 16 bits for the total header length. */
  if (info_length > 65535)
  {
    my_printf_error(0, "MyISAM table '%s' has too many columns and/or "
                    "indexes and/or unique constraints.",
                    MYF(0), name + dirname_length(name));
    my_errno= HA_WRONG_CREATE_OPTION;
    goto err_no_lock;
  }

  bmove(share.state.header.file_version,(uchar*) myisam_file_magic,4);
  ci->old_options=options| (ci->old_options & HA_OPTION_TEMP_COMPRESS_RECORD ?
                        HA_OPTION_COMPRESS_RECORD |
                        HA_OPTION_TEMP_COMPRESS_RECORD: 0);
  mi_int2store(share.state.header.options,ci->old_options);
  mi_int2store(share.state.header.header_length,info_length);
  mi_int2store(share.state.header.state_info_length,MI_STATE_INFO_SIZE);
  mi_int2store(share.state.header.base_info_length,MI_BASE_INFO_SIZE);
  mi_int2store(share.state.header.base_pos,base_pos);
  share.state.header.language= (ci->language ?
                                ci->language : default_charset_info->number);
  share.state.header.max_block_size_index= max_key_block_length/MI_MIN_KEY_BLOCK_LENGTH;

  share.state.dellink = HA_OFFSET_ERROR;
  share.state.process=  (ulong) getpid();
  share.state.unique=   (ulong) 0;
  share.state.update_count=(ulong) 0;
  share.state.version=  (ulong) time((time_t*) 0);
  share.state.sortkey=  (ushort) ~0;
  share.state.auto_increment=ci->auto_increment;
  share.options=options;
  share.base.rec_reflength=pointer;
  /* Get estimate for index file length (this may be wrong for FT keys) */
  tmp= (tot_length + max_key_block_length * keys *
        MI_INDEX_BLOCK_MARGIN) / MI_MIN_KEY_BLOCK_LENGTH;
  /*
    use maximum of key_file_length we calculated and key_file_length value we
    got from MYI file header (see also myisampack.c:save_state)
  */
  share.base.key_reflength=
    mi_get_pointer_length(MY_MAX(ci->key_file_length, tmp), 3);
  share.base.keys= share.state.header.keys= keys;
  share.state.header.uniques= uniques;
  share.state.header.fulltext_keys= fulltext_keys;
  mi_int2store(share.state.header.key_parts,key_segs);
  mi_int2store(share.state.header.unique_key_parts,unique_key_parts);

  mi_set_all_keys_active(share.state.key_map, keys);
  aligned_key_start= my_round_up_to_next_power(max_key_block_length ?
                                               max_key_block_length :
                                               myisam_block_size);

  share.base.keystart= share.state.state.key_file_length=
    MY_ALIGN(info_length, aligned_key_start);
  share.base.max_key_block_length=max_key_block_length;
  share.base.max_key_length=ALIGN_SIZE(max_key_length+4);
  share.base.records=ci->max_rows;
  share.base.reloc=  ci->reloc_rows;
  share.base.reclength=real_reclength;
  share.base.pack_reclength=reclength+ test(options & HA_OPTION_CHECKSUM);
  share.base.max_pack_length=pack_reclength;
  share.base.min_pack_length=min_pack_length;
  share.base.pack_bits=packed;
  share.base.fields=fields;
  share.base.pack_fields=packed;

  /* max_data_file_length and max_key_file_length are recalculated on open */
  if (options & HA_OPTION_TMP_TABLE)
    share.base.max_data_file_length=(my_off_t) ci->data_file_length;

  share.base.min_block_length=
    (share.base.pack_reclength+3 < MI_EXTEND_BLOCK_LENGTH &&
     ! share.base.blobs) ?
    MY_MAX(share.base.pack_reclength, MI_MIN_BLOCK_LENGTH) :
    MI_EXTEND_BLOCK_LENGTH;
  if (! (flags & HA_DONT_TOUCH_DATA))
    share.state.create_time= (long) time((time_t*) 0);

  if (!internal_table)
    mysql_mutex_lock(&THR_LOCK_myisam);

  /*
    NOTE: For test_if_reopen() we need a real path name. Hence we need
    MY_RETURN_REAL_PATH for every fn_format(filename, ...).
  */
  if (ci->index_file_name)
  {
    char *iext= strrchr(ci->index_file_name, '.');
    int have_iext= iext && !strcmp(iext, MI_NAME_IEXT);
    if (options & HA_OPTION_TMP_TABLE)
    {
      char *path;
      /* chop off the table name, tempory tables use generated name */
      if ((path= strrchr(ci->index_file_name, FN_LIBCHAR)))
        *path= '\0';
      fn_format(filename, name, ci->index_file_name, MI_NAME_IEXT,
                MY_REPLACE_DIR | MY_UNPACK_FILENAME |
                MY_RETURN_REAL_PATH | MY_APPEND_EXT);
    }
    else
    {
      fn_format(filename, ci->index_file_name, "", MI_NAME_IEXT,
                MY_UNPACK_FILENAME | MY_RETURN_REAL_PATH |
                (have_iext ? MY_REPLACE_EXT : MY_APPEND_EXT));
    }
    fn_format(linkname, name, "", MI_NAME_IEXT,
              MY_UNPACK_FILENAME|MY_APPEND_EXT);
    linkname_ptr=linkname;
    /*
      Don't create the table if the link or file exists to ensure that one
      doesn't accidently destroy another table.
    */
    create_flag=0;
  }
  else
  {
    char *iext= strrchr(name, '.');
    int have_iext= iext && !strcmp(iext, MI_NAME_IEXT);
    fn_format(filename, name, "", MI_NAME_IEXT,
              MY_UNPACK_FILENAME | MY_RETURN_REAL_PATH |
              (have_iext ? MY_REPLACE_EXT : MY_APPEND_EXT));
    linkname_ptr=0;
    /* Replace the current file */
    create_flag=(flags & HA_CREATE_KEEP_FILES) ? 0 : MY_DELETE_OLD;
  }

  /*
    If a MRG_MyISAM table is in use, the mapped MyISAM tables are open,
    but no entry is made in the table cache for them.
    A TRUNCATE command checks for the table in the cache only and could
    be fooled to believe, the table is not open.
    Pull the emergency brake in this situation. (Bug #8306)

    NOTE: The filename is compared against unique_file_name of every
    open table. Hence we need a real path here.
  */
  if (!internal_table && test_if_reopen(filename))
  {
    my_printf_error(0, "MyISAM table '%s' is in use "
                    "(most likely by a MERGE table). Try FLUSH TABLES.",
                    MYF(0), name + dirname_length(name));
    my_errno= HA_ERR_TABLE_EXIST;
    goto err;
  }

  if ((file= mysql_file_create_with_symlink(mi_key_file_kfile,
                                            linkname_ptr, filename, 0,
                                            create_mode,
                                            MYF(MY_WME | create_flag))) < 0)
    goto err;
  errpos=1;

  if (!(flags & HA_DONT_TOUCH_DATA))
  {
    {
      if (ci->data_file_name)
      {
        char *dext= strrchr(ci->data_file_name, '.');
        int have_dext= dext && !strcmp(dext, MI_NAME_DEXT);

        if (options & HA_OPTION_TMP_TABLE)
        {
          char *path;
          /* chop off the table name, tempory tables use generated name */
          if ((path= strrchr(ci->data_file_name, FN_LIBCHAR)))
            *path= '\0';
          fn_format(filename, name, ci->data_file_name, MI_NAME_DEXT,
                    MY_REPLACE_DIR | MY_UNPACK_FILENAME | MY_APPEND_EXT);
        }
        else
        {
          fn_format(filename, ci->data_file_name, "", MI_NAME_DEXT,
                    MY_UNPACK_FILENAME |
                    (have_dext ? MY_REPLACE_EXT : MY_APPEND_EXT));
        }

        fn_format(linkname, name, "",MI_NAME_DEXT,
                  MY_UNPACK_FILENAME | MY_APPEND_EXT);
        linkname_ptr=linkname;
        create_flag=0;
      }
      else
      {
        fn_format(filename,name,"", MI_NAME_DEXT,
                  MY_UNPACK_FILENAME | MY_APPEND_EXT);
        linkname_ptr=0;
        create_flag=(flags & HA_CREATE_KEEP_FILES) ? 0 : MY_DELETE_OLD;
      }
      if ((dfile=
           mysql_file_create_with_symlink(mi_key_file_dfile,
                                          linkname_ptr, filename, 0,
                                          create_mode,
                                          MYF(MY_WME | create_flag))) < 0)
        goto err;
    }
    errpos=3;
  }

  DBUG_PRINT("info", ("write state info and base info"));
  if (mi_state_info_write(file, &share.state, 2) ||
      mi_base_info_write(file, &share.base))
    goto err;
#ifndef DBUG_OFF
  if ((uint) mysql_file_tell(file, MYF(0)) != base_pos + MI_BASE_INFO_SIZE)
  {
    uint pos=(uint) mysql_file_tell(file, MYF(0));
    DBUG_PRINT("warning",("base_length: %d  != used_length: %d",
                          base_pos+ MI_BASE_INFO_SIZE, pos));
  }
#endif

  /* Write key and keyseg definitions */
  DBUG_PRINT("info", ("write key and keyseg definitions"));
  for (i=0 ; i < share.base.keys - uniques; i++)
  {
    uint sp_segs=(keydefs[i].flag & HA_SPATIAL) ? 2*SPDIMS : 0;

    if (mi_keydef_write(file, &keydefs[i]))
      goto err;
    for (j=0 ; j < keydefs[i].keysegs-sp_segs ; j++)
      if (mi_keyseg_write(file, &keydefs[i].seg[j]))
       goto err;
#ifdef HAVE_SPATIAL
    for (j=0 ; j < sp_segs ; j++)
    {
      HA_KEYSEG sseg;
      sseg.type=SPTYPE;
      sseg.language= 7;                         /* Binary */
      sseg.null_bit=0;
      sseg.bit_start=0;
      sseg.bit_end=0;
      sseg.bit_length= 0;
      sseg.bit_pos= 0;
      sseg.length=SPLEN;
      sseg.null_pos=0;
      sseg.start=j*SPLEN;
      sseg.flag= HA_SWAP_KEY;
      if (mi_keyseg_write(file, &sseg))
        goto err;
    }
#endif
  }
  /* Create extra keys for unique definitions */
  offset= real_reclength - uniques * MI_UNIQUE_HASH_LENGTH;
  memset(&tmp_keydef, 0, sizeof(tmp_keydef));
  memset(&tmp_keyseg, 0, sizeof(tmp_keyseg));
  for (i=0; i < uniques ; i++)
  {
    tmp_keydef.keysegs=1;
    tmp_keydef.flag=            HA_UNIQUE_CHECK;
    tmp_keydef.block_length=    (uint16)myisam_block_size;
    tmp_keydef.keylength=       MI_UNIQUE_HASH_LENGTH + pointer;
    tmp_keydef.minlength=tmp_keydef.maxlength=tmp_keydef.keylength;
    tmp_keyseg.type=            MI_UNIQUE_HASH_TYPE;
    tmp_keyseg.length=          MI_UNIQUE_HASH_LENGTH;
    tmp_keyseg.start=           offset;
    offset+=                    MI_UNIQUE_HASH_LENGTH;
    if (mi_keydef_write(file,&tmp_keydef) ||
        mi_keyseg_write(file,(&tmp_keyseg)))
      goto err;
  }

  /* Save unique definition */
  DBUG_PRINT("info", ("write unique definitions"));
  for (i=0 ; i < share.state.header.uniques ; i++)
  {
    HA_KEYSEG *keyseg_end;
    keyseg= uniquedefs[i].seg;
    if (mi_uniquedef_write(file, &uniquedefs[i]))
      goto err;
    for (keyseg= uniquedefs[i].seg, keyseg_end= keyseg+ uniquedefs[i].keysegs;
         keyseg < keyseg_end;
         keyseg++)
    {
      switch (keyseg->type) {
      case HA_KEYTYPE_VARTEXT1:
      case HA_KEYTYPE_VARTEXT2:
      case HA_KEYTYPE_VARBINARY1:
      case HA_KEYTYPE_VARBINARY2:
        if (!(keyseg->flag & HA_BLOB_PART))
        {
          keyseg->flag|= HA_VAR_LENGTH_PART;
          keyseg->bit_start= ((keyseg->type == HA_KEYTYPE_VARTEXT1 ||
                               keyseg->type == HA_KEYTYPE_VARBINARY1) ?
                              1 : 2);
        }
        break;
      default:
        break;
      }
      if (mi_keyseg_write(file, keyseg))
        goto err;
    }
  }
  DBUG_PRINT("info", ("write field definitions"));
  for (i=0 ; i < share.base.fields ; i++)
    if (mi_recinfo_write(file, &recinfo[i]))
      goto err;

#ifndef DBUG_OFF
  if ((uint) mysql_file_tell(file, MYF(0)) != info_length)
  {
    uint pos= (uint) mysql_file_tell(file, MYF(0));
    DBUG_PRINT("warning",("info_length: %d  != used_length: %d",
                          info_length, pos));
  }
#endif

        /* Enlarge files */
  DBUG_PRINT("info", ("enlarge to keystart: %lu", (ulong) share.base.keystart));
  if (mysql_file_chsize(file, (ulong) share.base.keystart, 0, MYF(0)))
    goto err;

  if (! (flags & HA_DONT_TOUCH_DATA))
  {
#ifdef USE_RELOC
    if (mysql_file_chsize(dfile, share.base.min_pack_length*ci->reloc_rows,
                          0, MYF(0)))
      goto err;
#endif
    errpos=2;
    if (mysql_file_close(dfile, MYF(0)))
      goto err;
  }
  errpos=0;
  if (!internal_table)
    mysql_mutex_unlock(&THR_LOCK_myisam);
  if (mysql_file_close(file, MYF(0)))
    goto err_no_lock;
  my_free(rec_per_key_part);
  DBUG_RETURN(0);

err:
  if (!internal_table)
    mysql_mutex_unlock(&THR_LOCK_myisam);

err_no_lock:
  save_errno=my_errno;
  switch (errpos) {
  case 3:
    (void) mysql_file_close(dfile, MYF(0));
    /* fall through */
  case 2:
  if (! (flags & HA_DONT_TOUCH_DATA))
    mysql_file_delete_with_symlink(mi_key_file_dfile,
                                   fn_format(filename, name, "", MI_NAME_DEXT,
                                             MY_UNPACK_FILENAME | MY_APPEND_EXT),
                                   MYF(0));
    /* fall through */
  case 1:
    (void) mysql_file_close(file, MYF(0));
    if (! (flags & HA_DONT_TOUCH_DATA))
      mysql_file_delete_with_symlink(mi_key_file_kfile,
                                     fn_format(filename, name, "", MI_NAME_IEXT,
                                               MY_UNPACK_FILENAME | MY_APPEND_EXT),
                                     MYF(0));
  }
  my_free(rec_per_key_part);
  DBUG_RETURN(my_errno=save_errno);             /* return the fatal errno */
}


uint mi_get_pointer_length(ulonglong file_length, uint def)
{
  DBUG_ASSERT(def >= 2 && def <= 7);
  if (file_length)                              /* If not default */
  {
#ifdef NOT_YET_READY_FOR_8_BYTE_POINTERS
    if (file_length >= ULL(1) << 56)
      def=8;
    else
#endif
    if (file_length >= ULL(1) << 48)
      def=7;
    else if (file_length >= ULL(1) << 40)
      def=6;
    else if (file_length >= ULL(1) << 32)
      def=5;
    else if (file_length >= ULL(1) << 24)
      def=4;
    else if (file_length >= ULL(1) << 16)
      def=3;
    else
      def=2;
  }
  return def;
}