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/* Copyright (C) 2003 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; 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
Please read ha_exmple.cc before reading this file.
Please keep in mind that the example storage engine implements all methods
that are required to be implemented. handler.h has a full list of methods
that you can implement.
*/
#ifdef __GNUC__
#pragma interface /* gcc class implementation */
#endif
/*
EXAMPLE_SHARE is a structure that will be shared amoung all open handlers
The example implements the minimum of what you will probably need.
*/
typedef struct st_example_share {
char *table_name;
uint table_name_length,use_count;
pthread_mutex_t mutex;
THR_LOCK lock;
} EXAMPLE_SHARE;
/*
Class definition for the storage engine
*/
class ha_example: public handler
{
THR_LOCK_DATA lock; /* MySQL lock */
EXAMPLE_SHARE *share; /* Shared lock info */
public:
ha_example(TABLE *table): handler(table)
{
}
~ha_example()
{
}
/* The name that will be used for display purposes */
const char *table_type() const { return "EXAMPLE"; }
/* The name of the index type that will be used for display */
const char *index_type(uint inx) { return "NONE"; }
const char **bas_ext() const;
/*
This is a list of flags that says what the storage engine
implements. The current table flags are documented in
table_flags.
*/
ulong table_flags() const
{
return 0;
}
/*
This is a list of flags that says how the storage engine
implements indexes. The current index flags are documented in
handler.h. If you do not implement indexes, just return zero
here.
*/
ulong index_flags(uint inx) const
{
return 0;
}
/*
unireg.cc will call the following to make sure that the storage engine can
handle the data it is about to send.
*/
uint max_record_length() const { return HA_MAX_REC_LENGTH; }
uint max_keys() const { return 0; }
uint max_key_parts() const { return 0; }
uint max_key_length() const { return 0; }
/*
Called in test_quick_select to determine if indexes should be used.
*/
virtual double scan_time() { return (double) (records+deleted) / 20.0+10; }
/*
The next method will never be called if you do not implement indexes.
*/
virtual double read_time(ha_rows rows) { return (double) rows / 20.0+1; }
/*
Everything below are methods that we implment in ha_example.cc.
*/
int open(const char *name, int mode, uint test_if_locked);
int close(void);
int write_row(byte * buf);
int update_row(const byte * old_data, byte * new_data);
int delete_row(const byte * buf);
int index_read(byte * buf, const byte * key,
uint key_len, enum ha_rkey_function find_flag);
int index_read_idx(byte * buf, uint idx, const byte * key,
uint key_len, enum ha_rkey_function find_flag);
int index_next(byte * buf);
int index_prev(byte * buf);
int index_first(byte * buf);
int index_last(byte * buf);
int rnd_init(bool scan=1);
int rnd_next(byte *buf);
int rnd_pos(byte * buf, byte *pos);
void position(const byte *record);
void info(uint);
int extra(enum ha_extra_function operation);
int reset(void);
int external_lock(THD *thd, int lock_type);
int delete_all_rows(void);
ha_rows records_in_range(uint inx, key_range *min_key,
key_range *max_key);
int delete_table(const char *from);
int rename_table(const char * from, const char * to);
int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info);
THR_LOCK_DATA **store_lock(THD *thd, THR_LOCK_DATA **to,
enum thr_lock_type lock_type);
};
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