~drizzle-trunk/drizzle/development

/* Copyright (C) 2000-2006 MySQL AB

   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/* The old structures from unireg */

struct st_table;

class Field;

typedef struct st_date_time_format {

  uchar positions[8];

  char  time_separator;			/* Separator between hour and minute */

  uint flag;				/* For future */

  LEX_STRING format;

} DATE_TIME_FORMAT;

typedef struct st_keyfile_info {	/* used with ha_info() */

  uchar ref[MAX_REFLENGTH];		/* Pointer to current row */

  uchar dupp_ref[MAX_REFLENGTH];	/* Pointer to dupp row */

  uint ref_length;			/* Length of ref (1-8) */

  uint block_size;			/* index block size */

  File filenr;				/* (uniq) filenr for table */

  ha_rows records;			/* Records i datafilen */

  ha_rows deleted;			/* Deleted records */

  uint64_t data_file_length;		/* Length off data file */

  uint64_t max_data_file_length;	/* Length off data file */

  uint64_t index_file_length;

  uint64_t max_index_file_length;

  uint64_t delete_length;		/* Free bytes */

  uint64_t auto_increment_value;

  int errkey,sortkey;			/* Last errorkey and sorted by */

  time_t create_time;			/* When table was created */

  time_t check_time;

  time_t update_time;

  ulong mean_rec_length;		/* physical reclength */

} KEYFILE_INFO;

typedef struct st_key_part_info {	/* Info about a key part */

  Field *field;

  uint	offset;				/* offset in record (from 0) */

  uint	null_offset;			/* Offset to null_bit in record */

  /* Length of key part in bytes, excluding NULL flag and length bytes */

  uint16 length;

  /*

    Number of bytes required to store the keypart value. This may be

    different from the "length" field as it also counts

     - possible NULL-flag byte (see HA_KEY_NULL_LENGTH) [if null_bit != 0,

       the first byte stored at offset is 1 if null, 0 if non-null; the

       actual value is stored from offset+1].

     - possible HA_KEY_BLOB_LENGTH bytes needed to store actual value length.

  */

  uint16 store_length;

  uint16 key_type;

  uint16 fieldnr;			/* Fieldnum in UNIREG (1,2,3,...) */

  uint16 key_part_flag;			/* 0 or HA_REVERSE_SORT */

  uint8 type;

  uint8 null_bit;			/* Position to null_bit */

} KEY_PART_INFO ;

typedef struct st_key {

  uint	key_length;			/* Tot length of key */

  ulong flags;                          /* dupp key and pack flags */

  uint	key_parts;			/* How many key_parts */

  uint  extra_length;

  uint	usable_key_parts;		/* Should normally be = key_parts */

  uint  block_size;

  enum  ha_key_alg algorithm;

  KEY_PART_INFO *key_part;

  char	*name;				/* Name of key */

  /*

    Array of AVG(#records with the same field value) for 1st ... Nth key part.

    0 means 'not known'.

    For temporary heap tables this member is NULL.

  */

  ulong *rec_per_key;

  struct st_table *table;

  LEX_STRING comment;

} KEY;

struct st_join_table;

typedef struct st_reginfo {		/* Extra info about reg */

  struct st_join_table *join_tab;	/* Used by SELECT() */

  enum thr_lock_type lock_type;		/* How database is used */

  bool not_exists_optimize;

  bool impossible_range;

} REGINFO;

struct st_read_record;				/* For referense later */

class SQL_SELECT;

class THD;

class handler;

struct st_join_table;

typedef struct st_read_record {			/* Parameter to read_record */

  struct st_table *table;			/* Head-form */

  handler *file;

  struct st_table **forms;			/* head and ref forms */

  int (*read_record)(struct st_read_record *);

  THD *thd;

  SQL_SELECT *select;

  uint cache_records;

  uint ref_length,struct_length,reclength,rec_cache_size,error_offset;

  uint index;

  uchar *ref_pos;				/* pointer to form->refpos */

  uchar *record;

  uchar *rec_buf;                /* to read field values  after filesort */

  uchar	*cache,*cache_pos,*cache_end,*read_positions;

  IO_CACHE *io_cache;

  bool print_error, ignore_not_found_rows;

  struct st_join_table *do_insideout_scan;

} READ_RECORD;

/*

  Originally MySQL used MYSQL_TIME structure inside server only, but since

  4.1 it's exported to user in the new client API. Define aliases for

  new names to keep existing code simple.

*/

typedef enum enum_mysql_timestamp_type timestamp_type;

typedef struct {

  ulong year,month,day,hour;

  uint64_t minute,second,second_part;

  bool neg;

} INTERVAL;

typedef struct st_known_date_time_format {

  const char *format_name;

  const char *date_format;

  const char *datetime_format;

  const char *time_format;

} KNOWN_DATE_TIME_FORMAT;

enum SHOW_COMP_OPTION { SHOW_OPTION_YES, SHOW_OPTION_NO, SHOW_OPTION_DISABLED};

extern const char *show_comp_option_name[];

typedef int *(*update_var)(THD *, struct st_mysql_show_var *);

typedef struct	st_lex_user {

  LEX_STRING user, host, password;

} LEX_USER;

/*

  This structure specifies the maximum amount of resources which

  can be consumed by each account. Zero value of a member means

  there is no limit.

*/

typedef struct user_resources {

  /* Maximum number of queries/statements per hour. */

  uint questions;

  /*

     Maximum number of updating statements per hour (which statements are

     updating is defined by sql_command_flags array).

  */

  uint updates;

  /* Maximum number of connections established per hour. */

  uint conn_per_hour;

  /* Maximum number of concurrent connections. */

  uint user_conn;

  /*

     Values of this enum and specified_limits member are used by the

     parser to store which user limits were specified in GRANT statement.

  */

  enum {QUERIES_PER_HOUR= 1, UPDATES_PER_HOUR= 2, CONNECTIONS_PER_HOUR= 4,

        USER_CONNECTIONS= 8};

  uint specified_limits;

} USER_RESOURCES;

/*

  This structure is used for counting resources consumed and for checking

  them against specified user limits.

*/

typedef struct  user_conn {

  /*

     Pointer to user+host key (pair separated by '\0') defining the entity

     for which resources are counted (By default it is user account thus

     priv_user/priv_host pair is used. If --old-style-user-limits option

     is enabled, resources are counted for each user+host separately).

  */

  char *user;

  /* Pointer to host part of the key. */

  char *host;

  /**

     The moment of time when per hour counters were reset last time

     (i.e. start of "hour" for conn_per_hour, updates, questions counters).

  */

  uint64_t reset_utime;

  /* Total length of the key. */

  uint len;

  /* Current amount of concurrent connections for this account. */

  uint connections;

  /*

     Current number of connections per hour, number of updating statements

     per hour and total number of statements per hour for this account.

  */

  uint conn_per_hour, updates, questions;

  /* Maximum amount of resources which account is allowed to consume. */

  USER_RESOURCES user_resources;

} USER_CONN;

	/* Bits in form->update */

#define REG_MAKE_DUPP		1	/* Make a copy of record when read */

#define REG_NEW_RECORD		2	/* Write a new record if not found */

#define REG_UPDATE		4	/* Uppdate record */

#define REG_DELETE		8	/* Delete found record */

#define REG_PROG		16	/* User is updating database */

#define REG_CLEAR_AFTER_WRITE	32

#define REG_MAY_BE_UPDATED	64

#define REG_AUTO_UPDATE		64	/* Used in D-forms for scroll-tables */

#define REG_OVERWRITE		128

#define REG_SKIP_DUP		256

	/* Bits in form->status */

#define STATUS_NO_RECORD	(1+2)	/* Record isn't usably */

#define STATUS_GARBAGE		1

#define STATUS_NOT_FOUND	2	/* No record in database when needed */

#define STATUS_NO_PARENT	4	/* Parent record wasn't found */

#define STATUS_NOT_READ		8	/* Record isn't read */

#define STATUS_UPDATED		16	/* Record is updated by formula */

#define STATUS_NULL_ROW		32	/* table->null_row is set */

#define STATUS_DELETED		64

/*

  Such interval is "discrete": it is the set of

  { auto_inc_interval_min + k * increment,

    0 <= k <= (auto_inc_interval_values-1) }

  Where "increment" is maintained separately by the user of this class (and is

  currently only thd->variables.auto_increment_increment).

  It mustn't derive from Sql_alloc, because SET INSERT_ID needs to

  allocate memory which must stay allocated for use by the next statement.

*/

class Discrete_interval {

private:

  uint64_t interval_min;

  uint64_t interval_values;

  uint64_t  interval_max;    // excluded bound. Redundant.

public:

  Discrete_interval *next;    // used when linked into Discrete_intervals_list

  void replace(uint64_t start, uint64_t val, uint64_t incr)

  {

    interval_min=    start;

    interval_values= val;

    interval_max=    (val == UINT64_MAX) ? val : start + val * incr;

  }

  Discrete_interval(uint64_t start, uint64_t val, uint64_t incr) :

    next(NULL) { replace(start, val, incr); };

  Discrete_interval() : next(NULL) { replace(0, 0, 0); };

  uint64_t minimum() const { return interval_min;    };

  uint64_t values()  const { return interval_values; };

  uint64_t maximum() const { return interval_max;    };

  /*

    If appending [3,5] to [1,2], we merge both in [1,5] (they should have the

    same increment for that, user of the class has to ensure that). That is

    just a space optimization. Returns 0 if merge succeeded.

  */

  bool merge_if_contiguous(uint64_t start, uint64_t val, uint64_t incr)

  {

    if (interval_max == start)

    {

      if (val == UINT64_MAX)

      {

        interval_values=   interval_max= val;

      }

      else

      {

        interval_values+=  val;

        interval_max=      start + val * incr;

      }

      return 0;

    }

    return 1;

  };

};

/* List of Discrete_interval objects */

class Discrete_intervals_list {

private:

  Discrete_interval        *head;

  Discrete_interval        *tail;

  /*

    When many intervals are provided at the beginning of the execution of a

    statement (in a replication slave or SET INSERT_ID), "current" points to

    the interval being consumed by the thread now (so "current" goes from

    "head" to "tail" then to NULL).

  */

  Discrete_interval        *current;

  uint                  elements; // number of elements

  /* helper function for copy construct and assignment operator */

  void copy_(const Discrete_intervals_list& from)

  {

    for (Discrete_interval *i= from.head; i; i= i->next)

    {

      Discrete_interval j= *i;

      append(&j);

    }

  }

public:

  Discrete_intervals_list() : head(NULL), current(NULL), elements(0) {};

  Discrete_intervals_list(const Discrete_intervals_list& from)

  {

    copy_(from);

  }

  void operator=(const Discrete_intervals_list& from)

  {

    empty();

    copy_(from);

  }

  void empty_no_free()

  {

    head= current= NULL;

    elements= 0;

  }

  void empty()

  {

    for (Discrete_interval *i= head; i;)

    {

      Discrete_interval *next= i->next;

      delete i;

      i= next;

    }

    empty_no_free();

  }

  const Discrete_interval* get_next()

  {

    Discrete_interval *tmp= current;

    if (current != NULL)

      current= current->next;

    return tmp;

  }

  ~Discrete_intervals_list() { empty(); };

  bool append(uint64_t start, uint64_t val, uint64_t incr);

  bool append(Discrete_interval *interval);

  uint64_t minimum()     const { return (head ? head->minimum() : 0); };

  uint64_t maximum()     const { return (head ? tail->maximum() : 0); };

  uint      nb_elements() const { return elements; }

};