/*
   Copyright (c) 2000, 2014, 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
*/

/*
  Functions to create a unireg form-file from a FIELD and a fieldname-fieldinfo
  struct.
  In the following functions FIELD * is an ordinary field-structure with
  the following exeptions:
    sc_length,typepos,row,kol,dtype,regnr and field need not to be set.
    str is a (long) to record position where 0 is the first position.
*/

#include "sql_priv.h"
#include "unireg.h"
#include "sql_partition.h"                    // struct partition_info
#include "sql_table.h"                        // validate_comment_length   
#include "sql_class.h"                  // THD, Internal_error_handler
#include <m_ctype.h>
#include <assert.h>

#include <algorithm>

using std::min;
using std::max;

#define FCOMP			17		/* Bytes for a packed field */

static uchar * pack_screens(List<Create_field> &create_fields,
			    uint *info_length, uint *screens, bool small_file);
static uint pack_keys(uchar *keybuff,uint key_count, KEY *key_info,
                      ulong data_offset);
static bool pack_header(uchar *forminfo,enum legacy_db_type table_type,
			List<Create_field> &create_fields,
			uint info_length, uint screens, uint table_options,
			ulong data_offset, handler *file);
static uint get_interval_id(uint *,List<Create_field> &, Create_field *);
static bool pack_fields(File file, List<Create_field> &create_fields,
                        ulong data_offset);
static bool make_empty_rec(THD *thd, int file,
			   uint table_options,
			   List<Create_field> &create_fields,
			   uint reclength, ulong data_offset,
                           handler *handler);
/**
  An interceptor to hijack ER_TOO_MANY_FIELDS error from
  pack_screens and retry again without UNIREG screens.

  XXX: what is a UNIREG  screen?
*/

struct Pack_header_error_handler: public Internal_error_handler
{
  virtual bool handle_condition(THD *thd,
                                uint sql_errno,
                                const char* sqlstate,
                                Sql_condition::enum_severity_level *level,
                                const char* msg,
                                Sql_condition ** cond_hdl);
  bool is_handled;
  Pack_header_error_handler() :is_handled(FALSE) {}
};


bool
Pack_header_error_handler::
handle_condition(THD *,
                 uint sql_errno,
                 const char*,
                 Sql_condition::enum_severity_level*,
                 const char*,
                 Sql_condition ** cond_hdl)
{
  *cond_hdl= NULL;
  is_handled= (sql_errno == ER_TOO_MANY_FIELDS);
  return is_handled;
}

/*
  Create a frm (table definition) file

  SYNOPSIS
    mysql_create_frm()
    thd			Thread handler
    file_name		Path for file (including database and .frm)
    db                  Name of database
    table               Name of table
    create_info		create info parameters
    create_fields	Fields to create
    keys		number of keys to create
    key_info		Keys to create
    db_file		Handler to use. May be zero, in which case we use
			create_info->db_type
  RETURN
    false  ok
    true   error
*/

bool mysql_create_frm(THD *thd, const char *file_name,
                      const char *db, const char *table,
		      HA_CREATE_INFO *create_info,
		      List<Create_field> &create_fields,
		      uint keys, KEY *key_info,
		      handler *db_file)
{
  LEX_STRING str_db_type;
  uint reclength, info_length, screens, key_info_length, maxlength, i;
  ulong key_buff_length;
  File file;
  ulong filepos, data_offset;
  uchar fileinfo[64],forminfo[288],*keybuff, *forminfo_p= forminfo;
  uchar *screen_buff= NULL;
  char buff[128];
#ifdef WITH_PARTITION_STORAGE_ENGINE
  partition_info *part_info= thd->work_part_info;
#endif
  Pack_header_error_handler pack_header_error_handler;
  int error;
  const uint format_section_header_size= 8;
  uint format_section_length;
  size_t tablespace_length= 0;
  DBUG_ENTER("mysql_create_frm");

  DBUG_ASSERT(*fn_rext((char*)file_name)); // Check .frm extension

  if (!(screen_buff=pack_screens(create_fields,&info_length,&screens,0)))
    DBUG_RETURN(1);
  DBUG_ASSERT(db_file != NULL);

 /* If fixed row records, we need one bit to check for deleted rows */
  if (!(create_info->table_options & HA_OPTION_PACK_RECORD))
    create_info->null_bits++;
  data_offset= (create_info->null_bits + 7) / 8;

  thd->push_internal_handler(&pack_header_error_handler);

  error= pack_header(forminfo, ha_legacy_type(create_info->db_type),
                     create_fields,info_length,
                     screens, create_info->table_options,
                     data_offset, db_file);

  thd->pop_internal_handler();

  if (error)
  {
    my_free(screen_buff);
    if (! pack_header_error_handler.is_handled)
      DBUG_RETURN(1);

    // Try again without UNIREG screens (to get more columns)
    if (!(screen_buff=pack_screens(create_fields,&info_length,&screens,1)))
      DBUG_RETURN(1);
    if (pack_header(forminfo, ha_legacy_type(create_info->db_type),
                    create_fields,info_length,
		    screens, create_info->table_options, data_offset, db_file))
    {
      my_free(screen_buff);
      DBUG_RETURN(1);
    }
  }
  reclength=uint2korr(forminfo+266);

  /* Calculate extra data segment length */
  str_db_type.str= (char *) ha_resolve_storage_engine_name(create_info->db_type);
  str_db_type.length= strlen(str_db_type.str);
  /* str_db_type */
  create_info->extra_size= (2 + str_db_type.length +
                            2 + create_info->connect_string.length);
  /*
    Partition:
      Length of partition info = 4 byte
      Potential NULL byte at end of partition info string = 1 byte
      Indicator if auto-partitioned table = 1 byte
      => Total 6 byte
  */
  create_info->extra_size+= 6;
#ifdef WITH_PARTITION_STORAGE_ENGINE
  if (part_info)
  {
    create_info->extra_size+= part_info->part_info_len;
  }
#endif

  for (i= 0; i < keys; i++)
  {
    if (key_info[i].parser_name)
      create_info->extra_size+= key_info[i].parser_name->length + 1;
  }
  /*
    This gives us the byte-position of the character at
    (character-position, not byte-position) TABLE_COMMENT_MAXLEN.
    The trick here is that character-positions start at 0, so the last
    character in a maximum-allowed length string would be at char-pos
    MAXLEN-1; charpos MAXLEN will be the position of the terminator.
    Consequently, bytepos(charpos(MAXLEN)) should be equal to
    comment[length] (which should also be the terminator, or at least
    the first byte after the payload in the strict sense). If this is
    not so (bytepos(charpos(MAXLEN)) comes /before/ the end of the
    string), the string is too long.

    For additional credit, realise that UTF-8 has 1-3 bytes before 6.0,
    and 1-4 bytes in 6.0 (6.0 also has UTF-32).
  */
  if (create_info->comment.length > TABLE_COMMENT_MAXLEN)
  {
    const char *real_table_name= table;
    List_iterator<Create_field> it(create_fields);
    Create_field *field;
    while ((field=it++))
    {
      if (field->field && field->field->table &&
        (real_table_name= field->field->table->s->table_name.str))
         break;
    }
    if (validate_comment_length(thd,
                                create_info->comment.str,
                                &create_info->comment.length,
                                TABLE_COMMENT_MAXLEN,
                                ER_TOO_LONG_TABLE_COMMENT,
                                real_table_name))
    {
      my_free(screen_buff);
      DBUG_RETURN(true);
    }
  }
  /*
    If table comment is longer than TABLE_COMMENT_INLINE_MAXLEN bytes,
    store the comment in an extra segment (up to TABLE_COMMENT_MAXLEN bytes).
    Pre 6.0, the limit was 60 characters, with no extra segment-handling.
  */
  if (create_info->comment.length > TABLE_COMMENT_INLINE_MAXLEN)
  {
    forminfo[46]=255;
    create_info->extra_size+= 2 + create_info->comment.length;
  }
  else{
    strmake((char*) forminfo+47, create_info->comment.str ?
            create_info->comment.str : "", create_info->comment.length);
    forminfo[46]=(uchar) create_info->comment.length;
  }

  /*
    Add room in extra segment for "format section" with additional
    table and column properties
  */
  if (create_info->tablespace)
    tablespace_length= strlen(create_info->tablespace);
  format_section_length=
    format_section_header_size +
    tablespace_length + 1 +
    create_fields.elements;
  create_info->extra_size+= format_section_length;

  if ((file=create_frm(thd, file_name, db, table, reclength, fileinfo,
		       create_info, keys, key_info)) < 0)
  {
    my_free(screen_buff);
    DBUG_RETURN(1);
  }

  key_buff_length= uint4korr(fileinfo+47);
  keybuff=(uchar*) my_malloc(key_memory_frm,
                             key_buff_length, MYF(0));
  key_info_length= pack_keys(keybuff, keys, key_info, data_offset);

  /*
    Ensure that there are no forms in this newly created form file.
    Even if the form file exists, create_frm must truncate it to
    ensure one form per form file.
  */
  DBUG_ASSERT(uint2korr(fileinfo+8) == 0);

  if (!(filepos= make_new_entry(file, fileinfo, NULL, "")))
    goto err;
  maxlength=(uint) next_io_size((ulong) (uint2korr(forminfo_p)+1000));
  int2store(forminfo+2,maxlength);
  int4store(fileinfo+10,(ulong) (filepos+maxlength));
  fileinfo[26]= (uchar) MY_TEST((create_info->max_rows == 1) &&
                                (create_info->min_rows == 1) && (keys == 0));
  int2store(fileinfo+28,key_info_length);

#ifdef WITH_PARTITION_STORAGE_ENGINE
  if (part_info)
  {
    fileinfo[61]= (uchar) ha_legacy_type(part_info->default_engine_type);
    DBUG_PRINT("info", ("part_db_type = %d", fileinfo[61]));
  }
#endif
  int2store(fileinfo+59,db_file->extra_rec_buf_length());

  if (mysql_file_pwrite(file, fileinfo, 64, 0L, MYF_RW) ||
      mysql_file_pwrite(file, keybuff, key_info_length,
                        (ulong) uint2korr(fileinfo+6), MYF_RW))
    goto err;
  mysql_file_seek(file,
                  (ulong) uint2korr(fileinfo+6) + (ulong) key_buff_length,
                  MY_SEEK_SET, MYF(0));
  if (make_empty_rec(thd,file,
                     create_info->table_options,
		     create_fields,reclength, data_offset, db_file))
    goto err;

  int2store(buff, static_cast<uint16>(create_info->connect_string.length));
  if (mysql_file_write(file, (const uchar*)buff, 2, MYF(MY_NABP)) ||
      mysql_file_write(file, (const uchar*)create_info->connect_string.str,
               create_info->connect_string.length, MYF(MY_NABP)))
      goto err;

  int2store(buff, static_cast<uint16>(str_db_type.length));
  if (mysql_file_write(file, (const uchar*)buff, 2, MYF(MY_NABP)) ||
      mysql_file_write(file, (const uchar*)str_db_type.str,
               str_db_type.length, MYF(MY_NABP)))
    goto err;

#ifdef WITH_PARTITION_STORAGE_ENGINE
  if (part_info)
  {
    char auto_partitioned= part_info->is_auto_partitioned ? 1 : 0;
    int4store(buff, static_cast<uint32>(part_info->part_info_len));
    if (mysql_file_write(file, (const uchar*)buff, 4, MYF_RW) ||
        mysql_file_write(file, (const uchar*)part_info->part_info_string,
                 part_info->part_info_len + 1, MYF_RW) ||
        mysql_file_write(file, (const uchar*)&auto_partitioned, 1, MYF_RW))
      goto err;
  }
  else
#endif
  {
    memset(buff, 0, 6);
    if (mysql_file_write(file, (uchar*) buff, 6, MYF_RW))
      goto err;
  }
  for (i= 0; i < keys; i++)
  {
    if (key_info[i].parser_name)
    {
      if (mysql_file_write(file, (const uchar*)key_info[i].parser_name->str,
                           key_info[i].parser_name->length + 1, MYF(MY_NABP)))
        goto err;
    }
  }
  if (forminfo[46] == (uchar)255)
  {
    uchar comment_length_buff[2];
    int2store(comment_length_buff, static_cast<uint16>(create_info->comment.length));
    if (mysql_file_write(file, comment_length_buff, 2, MYF(MY_NABP)) ||
        mysql_file_write(file, (uchar*) create_info->comment.str,
                         create_info->comment.length, MYF(MY_NABP)))
      goto err;
  }

  /* "Format section" with additional table and column properties */
  {
    uchar *ptr, *format_section_buff;
    if (!(format_section_buff=(uchar*) my_malloc(key_memory_frm,
                                                 format_section_length,
                                                 MYF(MY_WME))))
      goto err;
    ptr= format_section_buff;

    /* header */
    const uint format_section_flags=
      create_info->storage_media; // 3 bits
    const uint format_section_unused= 0;
    int2store(ptr+0, format_section_length);
    int4store(ptr+2, format_section_flags);
    int2store(ptr+6, format_section_unused);
    ptr+= format_section_header_size;

    /* tablespace name */
    if (tablespace_length > 0)
      memcpy(ptr, create_info->tablespace, tablespace_length);
    ptr+= tablespace_length;
    *ptr= 0; /* tablespace string terminating zero */
    ptr++;

    /* column properties  */
    Create_field *field;
    List_iterator<Create_field> it(create_fields);
    while ((field=it++))
    {
      const uchar field_storage= field->field_storage_type();
      const uchar field_column_format= field->column_format();
      const uchar field_flags=
        field_storage + (field_column_format << COLUMN_FORMAT_SHIFT);
      *ptr= field_flags;
      ptr++;
    }
    DBUG_ASSERT(format_section_buff + format_section_length == ptr);

    if (mysql_file_write(file, format_section_buff,
                         format_section_length, MYF_RW))
    {
      my_free(format_section_buff);
      goto err;
    }
    DBUG_PRINT("info", ("wrote format section, length: %u",
                        format_section_length));
    my_free(format_section_buff);
  }

  mysql_file_seek(file, filepos, MY_SEEK_SET, MYF(0));
  if (mysql_file_write(file, forminfo, 288, MYF_RW) ||
      mysql_file_write(file, screen_buff, info_length, MYF_RW) ||
      pack_fields(file, create_fields, data_offset))
    goto err;

  my_free(screen_buff);
  my_free(keybuff);

  if (opt_sync_frm && !(create_info->options & HA_LEX_CREATE_TMP_TABLE) &&
      (mysql_file_sync(file, MYF(MY_WME)) ||
       my_sync_dir_by_file(file_name, MYF(MY_WME))))
      goto err2;

  if (mysql_file_close(file, MYF(MY_WME)))
    goto err3;

  {
    /* 
      Restore all UCS2 intervals.
      HEX representation of them is not needed anymore.
    */
    List_iterator<Create_field> it(create_fields);
    Create_field *field;
    while ((field=it++))
    {
      if (field->save_interval)
      {
        field->interval= field->save_interval;
        field->save_interval= 0;
      }
    }
  }
  DBUG_RETURN(0);

err:
  my_free(screen_buff);
  my_free(keybuff);
err2:
  (void) mysql_file_close(file, MYF(MY_WME));
err3:
  mysql_file_delete(key_file_frm, file_name, MYF(0));
  DBUG_RETURN(1);
} /* mysql_create_frm */


/**
  Create a frm (table definition) file and the tables

  @param thd           Thread handler
  @param path          Name of file (including database, without .frm)
  @param db            Data base name
  @param table_name    Table name
  @param create_info   create info parameters
  @param create_fields Fields to create
  @param keys          number of keys to create
  @param key_info      Keys to create
  @param file          Handler to use
  @param no_ha_table   Indicates that only .FRM file (and PAR file if table
                       is partitioned) needs to be created and not a table
                       in the storage engine.

  @retval 0   ok
  @retval 1   error
*/

int rea_create_table(THD *thd, const char *path,
                     const char *db, const char *table_name,
                     HA_CREATE_INFO *create_info,
                     List<Create_field> &create_fields,
                     uint keys, KEY *key_info, handler *file,
                     bool no_ha_table)
{
  DBUG_ENTER("rea_create_table");

  char frm_name[FN_REFLEN + 1];
  strxnmov(frm_name, sizeof(frm_name) - 1, path, reg_ext, NullS);

  if (mysql_create_frm(thd, frm_name, db, table_name, create_info,
                       create_fields, keys, key_info, file))

    DBUG_RETURN(1);

  // Make sure mysql_create_frm din't remove extension
  DBUG_ASSERT(*fn_rext(frm_name));
  if (thd->variables.keep_files_on_create)
    create_info->options|= HA_CREATE_KEEP_FILES;

  if (file->ha_create_handler_files(path, NULL, CHF_CREATE_FLAG,
                                    create_info))
    goto err_handler_frm;

  if (!no_ha_table &&
       ha_create_table(thd, path, db, table_name, create_info, 0))
    goto err_handler;
  DBUG_RETURN(0);

err_handler:
  (void) file->ha_create_handler_files(path, NULL, CHF_DELETE_FLAG, create_info);

err_handler_frm:
  mysql_file_delete(key_file_frm, frm_name, MYF(0));
  DBUG_RETURN(1);
} /* rea_create_table */


	/* Pack screens to a screen for save in a form-file */

static uchar *pack_screens(List<Create_field> &create_fields,
                           uint *info_length, uint *screens,
                           bool small_file)
{
  uint i;
  uint row,start_row,end_row,fields_on_screen;
  size_t length;
  uint cols;
  uchar *info,*pos,*start_screen;
  uint fields=create_fields.elements;
  List_iterator<Create_field> it(create_fields);
  DBUG_ENTER("pack_screens");

  start_row=4; end_row=22; cols=80; fields_on_screen=end_row+1-start_row;

  *screens=(fields-1)/fields_on_screen+1;
  length= (*screens) * (SC_INFO_LENGTH+ (cols>> 1)+4);

  Create_field *field;
  while ((field=it++))
    length+= strlen(field->field_name)+1+TE_INFO_LENGTH+cols/2;

  if (!(info=(uchar*) my_malloc(key_memory_frm,
                                length,MYF(MY_WME))))
    DBUG_RETURN(0);

  start_screen=0;
  row=end_row;
  pos=info;
  it.rewind();
  for (i=0 ; i < fields ; i++)
  {
    Create_field *cfield=it++;
    if (row++ == end_row)
    {
      if (i)
      {
	length=(uint) (pos-start_screen);
	int2store(start_screen, static_cast<uint16>(length));
	start_screen[2]=(uchar) (fields_on_screen+1);
	start_screen[3]=(uchar) (fields_on_screen);
      }
      row=start_row;
      start_screen=pos;
      pos+=4;
      pos[0]= (uchar) start_row-2;	/* Header string */
      pos[1]= (uchar) (cols >> 2);
      pos[2]= (uchar) (cols >> 1) +1;
      strfill((char *) pos+3,(uint) (cols >> 1),' ');
      pos+=(cols >> 1)+4;
    }
    length= strlen(cfield->field_name);
    if (length > cols-3)
      length=cols-3;

    if (!small_file)
    {
      pos[0]=(uchar) row;
      pos[1]=0;
      pos[2]=(uchar) (length+1);
      pos=(uchar*) strmake((char*) pos+3,cfield->field_name,length)+1;
    }
    cfield->row=(uint8) row;
    cfield->col=(uint8) (length+1);
    cfield->sc_length= min<uint8>(cfield->length, cols - (length + 2));
  }
  length=(uint) (pos-start_screen);
  int2store(start_screen, static_cast<uint16>(length));
  start_screen[2]=(uchar) (row-start_row+2);
  start_screen[3]=(uchar) (row-start_row+1);

  *info_length=(uint) (pos-info);
  DBUG_RETURN(info);
} /* pack_screens */


	/* Pack keyinfo and keynames to keybuff for save in form-file. */

static uint pack_keys(uchar *keybuff, uint key_count, KEY *keyinfo,
                      ulong data_offset)
{
  uint key_parts,length;
  uchar *pos, *keyname_pos;
  KEY *key,*end;
  KEY_PART_INFO *key_part,*key_part_end;
  DBUG_ENTER("pack_keys");

  pos=keybuff+6;
  key_parts=0;
  for (key=keyinfo,end=keyinfo+key_count ; key != end ; key++)
  {
    int2store(pos, static_cast<uint16>(key->flags ^ HA_NOSAME));
    int2store(pos+2,key->key_length);
    pos[4]= (uchar) key->user_defined_key_parts;
    pos[5]= (uchar) key->algorithm;
    int2store(pos+6, key->block_size);
    pos+=8;
    key_parts+=key->user_defined_key_parts;
    DBUG_PRINT("loop", ("flags: %lu  key_parts: %d at 0x%lx",
                        key->flags, key->user_defined_key_parts,
                        (long) key->key_part));
    for (key_part=key->key_part,
           key_part_end= key_part + key->user_defined_key_parts ;
	 key_part != key_part_end ;
	 key_part++)

    {
      uint offset;
      DBUG_PRINT("loop",("field: %d  startpos: %lu  length: %d",
			 key_part->fieldnr, key_part->offset + data_offset,
                         key_part->length));
      int2store(pos,key_part->fieldnr+1+FIELD_NAME_USED);
      offset= (uint) (key_part->offset+data_offset+1);
      int2store(pos+2, offset);
      pos[4]=0;					// Sort order
      int2store(pos+5,key_part->key_type);
      int2store(pos+7,key_part->length);
      pos+=9;
    }
  }
	/* Save keynames */
  keyname_pos=pos;
  *pos++=(uchar) NAMES_SEP_CHAR;
  for (key=keyinfo ; key != end ; key++)
  {
    uchar *tmp=(uchar*) my_stpcpy((char*) pos,key->name);
    *tmp++= (uchar) NAMES_SEP_CHAR;
    *tmp=0;
    pos=tmp;
  }
  *(pos++)=0;
  for (key=keyinfo,end=keyinfo+key_count ; key != end ; key++)
  {
    if (key->flags & HA_USES_COMMENT)
    {
      int2store(pos, static_cast<uint16>(key->comment.length));
      uchar *tmp= (uchar*)my_stpnmov((char*) pos+2,key->comment.str,
                                     key->comment.length);
      pos= tmp;
    }
  }

  if (key_count > 127 || key_parts > 127)
  {
    keybuff[0]= (key_count & 0x7f) | 0x80;
    keybuff[1]= key_count >> 7;
    int2store(keybuff+2,key_parts);
  }
  else
  {
    keybuff[0]=(uchar) key_count;
    keybuff[1]=(uchar) key_parts;
    keybuff[2]= keybuff[3]= 0;
  }
  length=(uint) (pos-keyname_pos);
  int2store(keybuff+4,length);
  DBUG_RETURN((uint) (pos-keybuff));
} /* pack_keys */


	/* Make formheader */

static bool pack_header(uchar *forminfo, enum legacy_db_type table_type,
			List<Create_field> &create_fields,
                        uint info_length, uint screens, uint table_options,
                        ulong data_offset, handler *file)
{
  size_t length;
  uint int_count, int_length, no_empty, int_parts;
  uint time_stamp_pos,null_fields;
  size_t reclength, totlength, n_length, com_length;
  DBUG_ENTER("pack_header");

  if (create_fields.elements > MAX_FIELDS)
  {
    my_message(ER_TOO_MANY_FIELDS, ER(ER_TOO_MANY_FIELDS), MYF(0));
    DBUG_RETURN(1);
  }

  totlength= 0L;
  reclength= data_offset;
  no_empty=int_count=int_parts=int_length=time_stamp_pos=null_fields=
    com_length=0;
  n_length=2L;

	/* Check fields */

  List_iterator<Create_field> it(create_fields);
  Create_field *field;
  while ((field=it++))
  {
    if (validate_comment_length(current_thd,
                                field->comment.str,
                                &field->comment.length,
                                COLUMN_COMMENT_MAXLEN,
                                ER_TOO_LONG_FIELD_COMMENT,
                                (char *) field->field_name))
      DBUG_RETURN(true);
    totlength+= field->length;
    com_length+= field->comment.length;
    if (MTYP_TYPENR(field->unireg_check) == Field::NOEMPTY ||
	field->unireg_check & MTYP_NOEMPTY_BIT)
    {
      field->unireg_check= (Field::utype) ((uint) field->unireg_check |
					   MTYP_NOEMPTY_BIT);
      no_empty++;
    }
    /* 
      We mark first TIMESTAMP field with NOW() in DEFAULT or ON UPDATE 
      as auto-update field.
    */
    if (field->sql_type == MYSQL_TYPE_TIMESTAMP &&
        MTYP_TYPENR(field->unireg_check) != Field::NONE &&
	!time_stamp_pos)
      time_stamp_pos= (uint) field->offset+ (uint) data_offset + 1;
    length=field->pack_length;
    /* Ensure we don't have any bugs when generating offsets */
    DBUG_ASSERT(reclength == field->offset + data_offset);
    if (field->offset + data_offset + length > reclength)
      reclength= field->offset + data_offset + length;
    n_length+= strlen(field->field_name) + 1;
    field->interval_id=0;
    field->save_interval= 0;
    if (field->interval)
    {
      uint old_int_count=int_count;

      if (field->charset->mbminlen > 1)
      {
        /* 
          Escape UCS2 intervals using HEX notation to avoid
          problems with delimiters between enum elements.
          As the original representation is still needed in 
          the function make_empty_rec to create a record of
          filled with default values it is saved in save_interval
          The HEX representation is created from this copy.
        */
        field->save_interval= field->interval;
        field->interval= (TYPELIB*) sql_alloc(sizeof(TYPELIB));
        *field->interval= *field->save_interval; 
        field->interval->type_names= 
          (const char **) sql_alloc(sizeof(char*) * 
				    (field->interval->count+1));
        field->interval->type_names[field->interval->count]= 0;
        field->interval->type_lengths=
          (uint *) sql_alloc(sizeof(uint) * field->interval->count);
 
        for (uint pos= 0; pos < field->interval->count; pos++)
        {
          char *dst;
          const char *src= field->save_interval->type_names[pos];
          size_t hex_length;
          length= field->save_interval->type_lengths[pos];
          hex_length= length * 2;
          field->interval->type_lengths[pos]= hex_length;
          field->interval->type_names[pos]= dst= (char*) sql_alloc(hex_length +
                                                                   1);
          octet2hex(dst, src, length);
        }
      }

      field->interval_id=get_interval_id(&int_count,create_fields,field);
      if (old_int_count != int_count)
      {
	for (const char **pos=field->interval->type_names ; *pos ; pos++)
	  int_length+=(uint) strlen(*pos)+1;	// field + suffix prefix
	int_parts+=field->interval->count+1;
      }
    }
    if (f_maybe_null(field->pack_flag))
      null_fields++;
  }
  int_length+=int_count*2;			// 255 prefix + 0 suffix

	/* Save values in forminfo */

  if (reclength > (ulong) file->max_record_length())
  {
    my_error(ER_TOO_BIG_ROWSIZE, MYF(0), static_cast<long>(file->max_record_length()));
    DBUG_RETURN(1);
  }
  /* Hack to avoid bugs with small static rows in MySQL */
  reclength= max<size_t>(file->min_record_length(table_options), reclength);
  if (info_length+(ulong) create_fields.elements*FCOMP+288+
      n_length+int_length+com_length > 65535L || int_count > 255)
  {
    my_message(ER_TOO_MANY_FIELDS, ER(ER_TOO_MANY_FIELDS), MYF(0));
    DBUG_RETURN(1);
  }

  memset(forminfo, 0, 288);
  length=(info_length+create_fields.elements*FCOMP+288+n_length+int_length+
	  com_length);
  int2store(forminfo, static_cast<uint16>(length));
  forminfo[256] = (uint8) screens;
  int2store(forminfo+258,create_fields.elements);
  int2store(forminfo+260,info_length);
  int2store(forminfo+262, static_cast<uint16>(totlength));
  int2store(forminfo+264,no_empty);
  int2store(forminfo+266, static_cast<uint16>(reclength));
  int2store(forminfo+268, static_cast<uint16>(n_length));
  int2store(forminfo+270,int_count);
  int2store(forminfo+272,int_parts);
  int2store(forminfo+274,int_length);
  int2store(forminfo+276,time_stamp_pos);
  int2store(forminfo+278,80);			/* Columns needed */
  int2store(forminfo+280,22);			/* Rows needed */
  int2store(forminfo+282,null_fields);
  int2store(forminfo+284, static_cast<uint16>(com_length));
  /* Up to forminfo+288 is free to use for additional information */
  DBUG_RETURN(0);
} /* pack_header */


	/* get each unique interval each own id */

static uint get_interval_id(uint *int_count,List<Create_field> &create_fields,
			    Create_field *last_field)
{
  List_iterator<Create_field> it(create_fields);
  Create_field *field;
  TYPELIB *interval=last_field->interval;

  while ((field=it++) != last_field)
  {
    if (field->interval_id && field->interval->count == interval->count)
    {
      const char **a,**b;
      for (a=field->interval->type_names, b=interval->type_names ;
	   *a && !strcmp(*a,*b);
	   a++,b++) ;

      if (! *a)
      {
	return field->interval_id;		// Re-use last interval
      }
    }
  }
  return ++*int_count;				// New unique interval
}


	/* Save fields, fieldnames and intervals */

static bool pack_fields(File file, List<Create_field> &create_fields,
                        ulong data_offset)
{
  uint i;
  uint int_count;
  size_t comment_length= 0;
  uchar buff[MAX_FIELD_WIDTH];
  Create_field *field;
  DBUG_ENTER("pack_fields");

	/* Write field info */

  List_iterator<Create_field> it(create_fields);

  int_count=0;
  while ((field=it++))
  {
    uint recpos;
    buff[0]= (uchar) field->row;
    buff[1]= (uchar) field->col;
    buff[2]= (uchar) field->sc_length;
    int2store(buff+3, static_cast<uint16>(field->length));
    /* The +1 is here becasue the col offset in .frm file have offset 1 */
    recpos= field->offset+1 + (uint) data_offset;
    int3store(buff+5,recpos);
    int2store(buff+8,field->pack_flag);
    buff[10]= (uchar) field->unireg_check;
    buff[12]= (uchar) field->interval_id;
    buff[13]= (uchar) field->sql_type; 
    if (field->sql_type == MYSQL_TYPE_GEOMETRY)
    {
      buff[11]= 0;
      buff[14]= (uchar) field->geom_type;
    }
    else if (field->charset) 
    {
      buff[11]= (uchar) (field->charset->number >> 8);
      buff[14]= (uchar) field->charset->number;
    }
    else
    {
      buff[11]= buff[14]= 0;			// Numerical
    }
    int2store(buff+15, static_cast<uint16>(field->comment.length));
    comment_length+= field->comment.length;
    set_if_bigger(int_count,field->interval_id);
    if (mysql_file_write(file, buff, FCOMP, MYF_RW))
      DBUG_RETURN(1);
  }

	/* Write fieldnames */
  buff[0]=(uchar) NAMES_SEP_CHAR;
  if (mysql_file_write(file, buff, 1, MYF_RW))
    DBUG_RETURN(1);
  i=0;
  it.rewind();
  while ((field=it++))
  {
    char *pos= my_stpcpy((char*) buff,field->field_name);
    *pos++=NAMES_SEP_CHAR;
    if (i == create_fields.elements-1)
      *pos++=0;
    if (mysql_file_write(file, buff, (size_t) (pos-(char*) buff), MYF_RW))
      DBUG_RETURN(1);
    i++;
  }

	/* Write intervals */
  if (int_count)
  {
    String tmp((char*) buff,sizeof(buff), &my_charset_bin);
    tmp.length(0);
    it.rewind();
    int_count=0;
    while ((field=it++))
    {
      if (field->interval_id > int_count)
      {
        unsigned char  sep= 0;
        unsigned char  occ[256];
        uint           i;
        unsigned char *val= NULL;

        memset(occ, 0, sizeof(occ));

        for (i=0; (val= (unsigned char*) field->interval->type_names[i]); i++)
          for (uint j = 0; j < field->interval->type_lengths[i]; j++)
            occ[(unsigned int) (val[j])]= 1;

        if (!occ[(unsigned char)NAMES_SEP_CHAR])
          sep= (unsigned char) NAMES_SEP_CHAR;
        else if (!occ[(unsigned int)','])
          sep= ',';
        else
        {
          for (uint i=1; i<256; i++)
          {
            if(!occ[i])
            {
              sep= i;
              break;
            }
          }

          if(!sep)    /* disaster, enum uses all characters, none left as separator */
          {
            my_message(ER_WRONG_FIELD_TERMINATORS,ER(ER_WRONG_FIELD_TERMINATORS),
                       MYF(0));
            DBUG_RETURN(1);
          }
        }

        int_count= field->interval_id;
        tmp.append(sep);
        for (const char **pos=field->interval->type_names ; *pos ; pos++)
        {
          tmp.append(*pos);
          tmp.append(sep);
        }
        tmp.append('\0');                      // End of intervall
      }
    }
    if (mysql_file_write(file, (uchar*) tmp.ptr(), tmp.length(), MYF_RW))
      DBUG_RETURN(1);
  }
  if (comment_length)
  {
    it.rewind();
    int_count=0;
    while ((field=it++))
    {
      if (field->comment.length)
        if (mysql_file_write(file, (uchar*) field->comment.str,
                             field->comment.length, MYF_RW))
	  DBUG_RETURN(1);
    }
  }
  DBUG_RETURN(0);
}


/**
   Creates a record buffer consisting of default values for all columns and
   stores it in the formfile (.frm file.)

   The value stored for each column is

   - The default value if the column has one.
   - 1 if the column type is @c enum.
   - Special messages if the unireg type is YES or NO.
   - A buffer full of only zeroes in all other cases. This also happens if the
     default is a function.

   @param thd           The current session.
   @param file          The .frm file.
   @param table_options Describes how to pack the values in the buffer.
   @param create_fields A list of column definition objects.
   @param reclength     Length of the record buffer in bytes.
   @param data_offset   Offset inside the buffer before the values.
   @param handler       The storage engine.

   @retval true An error occured.
   @retval false Success.

*/

static bool make_empty_rec(THD *thd, File file,
			   uint table_options,
			   List<Create_field> &create_fields,
			   uint reclength,
                           ulong data_offset,
                           handler *handler)
{
  int error= 0;
  Field::utype type;
  uint null_count;
  uchar *buff,*null_pos;
  TABLE table;
  TABLE_SHARE share;
  Create_field *field;
  enum_check_fields old_count_cuted_fields= thd->count_cuted_fields;
  DBUG_ENTER("make_empty_rec");

  /* We need a table to generate columns for default values */
  memset(&table, 0, sizeof(table));
  memset(&share, 0, sizeof(share));
  table.s= &share;

  if (!(buff=(uchar*) my_malloc(key_memory_frm,
                                (size_t) reclength,MYF(MY_WME | MY_ZEROFILL))))
  {
    DBUG_RETURN(1);
  }

  table.in_use= thd;
  table.s->db_low_byte_first= handler->low_byte_first();

  null_count=0;
  if (!(table_options & HA_OPTION_PACK_RECORD))
  {
    null_count++;			// Need one bit for delete mark
    *buff|= 1;
  }
  null_pos= buff;

  List_iterator<Create_field> it(create_fields);
  thd->count_cuted_fields= CHECK_FIELD_WARN;    // To find wrong default values
  while ((field=it++))
  {
    Field *regfield= make_field(&share,
                                buff+field->offset + data_offset,
                                field->length,
                                null_pos + null_count / 8,
                                null_count & 7,
                                field->pack_flag,
                                field->sql_type,
                                field->charset,
                                field->geom_type,
                                field->unireg_check,
                                field->save_interval ? field->save_interval :
                                field->interval, 
                                field->field_name);
    if (!regfield)
    {
      error= 1;
      goto err;                                 // End of memory
    }

    /* save_in_field() will access regfield->table->in_use */
    regfield->init(&table);

    if (!(field->flags & NOT_NULL_FLAG))
    {
      regfield->set_null();
      null_count++;
    }

    if (field->sql_type == MYSQL_TYPE_BIT && !f_bit_as_char(field->pack_flag))
      null_count+= field->length & 7;

    type= (Field::utype) MTYP_TYPENR(field->unireg_check);

    if (field->def)
    {
      /*
        Storing the value of a function is pointless as this function may not
        be constant.
      */
      DBUG_ASSERT(field->def->type() != Item::FUNC_ITEM);
      type_conversion_status res= field->def->save_in_field(regfield, true);
      if (res != TYPE_OK && res != TYPE_NOTE_TIME_TRUNCATED &&
          res != TYPE_NOTE_TRUNCATED)
      {
        /*
          clear current error and report INVALID DEFAULT value error message
          */
        if (thd->is_error())
          thd->clear_error();

        my_error(ER_INVALID_DEFAULT, MYF(0), regfield->field_name);
        error= 1;
        /*
          Delete to avoid memory leak for fields that allocate extra
          memory (e.g Field_blob::value)
        */
        delete regfield;
        goto err;
      }
    }
    else if (regfield->real_type() == MYSQL_TYPE_ENUM &&
	     (field->flags & NOT_NULL_FLAG))
    {
      regfield->set_notnull();
      regfield->store((longlong) 1, TRUE);
    }
    else if (type == Field::YES)		// Old unireg type
      regfield->store(ER(ER_YES), strlen(ER(ER_YES)),system_charset_info);
    else if (type == Field::NO)			// Old unireg type
      regfield->store(ER(ER_NO), strlen(ER(ER_NO)),system_charset_info);
    else
      regfield->reset();
    /*
      Delete to avoid memory leak for fields that allocate extra
      memory (e.g Field_blob::value)
    */
    delete regfield;
  }
  DBUG_ASSERT(data_offset == ((null_count + 7) / 8));

  /*
    We need to set the unused bits to 1. If the number of bits is a multiple
    of 8 there are no unused bits.
  */
  if (null_count & 7)
    *(null_pos + null_count / 8)|= ~(((uchar) 1 << (null_count & 7)) - 1);

  error= mysql_file_write(file, buff, (size_t) reclength, MYF_RW) != 0;

err:
  my_free(buff);
  thd->count_cuted_fields= old_count_cuted_fields;
  DBUG_RETURN(error);
} /* make_empty_rec */
