~drizzle-trunk/drizzle/development

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

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

 *

 *  Copyright (C) 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; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  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

 */

/*

  This class is shared between different table objects. There is one

  instance of table share per one table in the database.

*/

class TABLE_SHARE

{

public:

  TABLE_SHARE() {}                    /* Remove gcc warning */

  /** Category of this table. */

  enum_table_category table_category;

  /* hash of field names (contains pointers to elements of field array) */

  HASH	name_hash;			/* hash of field names */

  MEM_ROOT mem_root;

  TYPELIB keynames;			/* Pointers to keynames */

  TYPELIB fieldnames;			/* Pointer to fieldnames */

  TYPELIB *intervals;			/* pointer to interval info */

  pthread_mutex_t mutex;                /* For locking the share  */

  pthread_cond_t cond;			/* To signal that share is ready */

  TABLE_SHARE *next,		/* Link to unused shares */

    **prev;

  /* The following is copied to each Table on OPEN */

  Field **field;

  Field **found_next_number_field;

  Field *timestamp_field;               /* Used only during open */

  KEY  *key_info;			/* data of keys in database */

  uint	*blob_field;			/* Index to blobs in Field arrray*/

  unsigned char	*default_values;		/* row with default values */

  LEX_STRING comment;			/* Comment about table */

  const CHARSET_INFO *table_charset; /* Default charset of string fields */

  MY_BITMAP all_set;

  /*

    Key which is used for looking-up table in table cache and in the list

    of thread's temporary tables. Has the form of:

      "database_name\0table_name\0" + optional part for temporary tables.

    Note that all three 'table_cache_key', 'db' and 'table_name' members

    must be set (and be non-zero) for tables in table cache. They also

    should correspond to each other.

    To ensure this one can use set_table_cache() methods.

  */

  LEX_STRING table_cache_key;

  LEX_STRING db;                        /* Pointer to db */

  LEX_STRING table_name;                /* Table name (for open) */

  LEX_STRING path;	/* Path to .frm file (from datadir) */

  LEX_STRING normalized_path;		/* unpack_filename(path) */

  LEX_STRING connect_string;

  /*

     Set of keys in use, implemented as a Bitmap.

     Excludes keys disabled by ALTER Table ... DISABLE KEYS.

  */

  key_map keys_in_use;

  key_map keys_for_keyread;

  ha_rows min_rows, max_rows;		/* create information */

  uint32_t   avg_row_length;		/* create information */

  uint32_t   block_size;                   /* create information */

  uint32_t   version, mysql_version;

  uint32_t   timestamp_offset;		/* Set to offset+1 of record */

  uint32_t   reclength;			/* Recordlength */

  uint32_t   stored_rec_length;         /* Stored record length

                                           (no generated-only virtual fields) */

  plugin_ref db_plugin;			/* storage engine plugin */

  inline handlerton *db_type() const	/* table_type for handler */

  {

    // assert(db_plugin);

    return db_plugin ? plugin_data(db_plugin, handlerton*) : NULL;

  }

  enum row_type row_type;		/* How rows are stored */

  enum tmp_table_type tmp_table;

  enum ha_choice page_checksum;

  uint32_t ref_count;       /* How many Table objects uses this */

  uint32_t open_count;			/* Number of tables in open list */

  uint32_t blob_ptr_size;			/* 4 or 8 */

  uint32_t key_block_size;			/* create key_block_size, if used */

  uint32_t null_bytes;

  uint32_t last_null_bit_pos;

  uint32_t fields;				/* Number of fields */

  uint32_t stored_fields;                   /* Number of stored fields

                                           (i.e. without generated-only ones) */

  uint32_t rec_buff_length;                 /* Size of table->record[] buffer */

  uint32_t keys, key_parts;

  uint32_t max_key_length, max_unique_length, total_key_length;

  uint32_t uniques;                         /* Number of UNIQUE index */

  uint32_t null_fields;			/* number of null fields */

  uint32_t blob_fields;			/* number of blob fields */

  uint32_t timestamp_field_offset;		/* Field number for timestamp field */

  uint32_t varchar_fields;                  /* number of varchar fields */

  uint32_t db_create_options;		/* Create options from database */

  uint32_t db_options_in_use;		/* Options in use */

  uint32_t db_record_offset;		/* if HA_REC_IN_SEQ */

  uint32_t rowid_field_offset;		/* Field_nr +1 to rowid field */

  /* Index of auto-updated TIMESTAMP field in field array */

  uint32_t primary_key;

  uint32_t next_number_index;               /* autoincrement key number */

  uint32_t next_number_key_offset;          /* autoinc keypart offset in a key */

  uint32_t next_number_keypart;             /* autoinc keypart number in a key */

  uint32_t error, open_errno, errarg;       /* error from open_table_def() */

  uint32_t column_bitmap_size;

  uint32_t vfields;                         /* Number of virtual fields */

  bool db_low_byte_first;		/* Portable row format */

  bool crashed;

  bool name_lock, replace_with_name_lock;

  bool waiting_on_cond;                 /* Protection against free */

  uint32_t table_map_id;                   /* for row-based replication */

  uint64_t table_map_version;

  /*

    Cache for row-based replication table share checks that does not

    need to be repeated. Possible values are: -1 when cache value is

    not calculated yet, 0 when table *shall not* be replicated, 1 when

    table *may* be replicated.

  */

  int cached_row_logging_check;

  /*

    Set share's table cache key and update its db and table name appropriately.

    SYNOPSIS

      set_table_cache_key()

        key_buff    Buffer with already built table cache key to be

                    referenced from share.

        key_length  Key length.

    NOTES

      Since 'key_buff' buffer will be referenced from share it should has same

      life-time as share itself.

      This method automatically ensures that TABLE_SHARE::table_name/db have

      appropriate values by using table cache key as their source.

  */

  void set_table_cache_key(char *key_buff, uint32_t key_length)

  {

    table_cache_key.str= key_buff;

    table_cache_key.length= key_length;

    /*

      Let us use the fact that the key is "db/0/table_name/0" + optional

      part for temporary tables.

    */

    db.str=            table_cache_key.str;

    db.length=         strlen(db.str);

    table_name.str=    db.str + db.length + 1;

    table_name.length= strlen(table_name.str);

  }

  /*

    Set share's table cache key and update its db and table name appropriately.

    SYNOPSIS

      set_table_cache_key()

        key_buff    Buffer to be used as storage for table cache key

                    (should be at least key_length bytes).

        key         Value for table cache key.

        key_length  Key length.

    NOTE

      Since 'key_buff' buffer will be used as storage for table cache key

      it should has same life-time as share itself.

  */

  void set_table_cache_key(char *key_buff, const char *key, uint32_t key_length)

  {

    memcpy(key_buff, key, key_length);

    set_table_cache_key(key_buff, key_length);

  }

  inline bool honor_global_locks()

  {

    return (table_category == TABLE_CATEGORY_USER);

  }

  inline uint32_t get_table_def_version()

  {

    return table_map_id;

  }

};