mariadb/sql/examples/ha_example.cc

300 lines
7.5 KiB
C++

/* 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 */
#ifdef __GNUC__
#pragma implementation // gcc: Class implementation
#endif
#include <mysql_priv.h>
#ifdef HAVE_EXAMPLE_DB
#include "ha_example.h"
/* Variables for example share methods */
pthread_mutex_t example_mutex;
static HASH example_open_tables;
static int example_init= 0;
static byte* example_get_key(EXAMPLE_SHARE *share,uint *length,
my_bool not_used __attribute__((unused)))
{
*length=share->table_name_length;
return (byte*) share->table_name;
}
/*
Example of simple lock controls.
*/
static EXAMPLE_SHARE *get_share(const char *table_name, TABLE *table)
{
EXAMPLE_SHARE *share;
uint length;
char *tmp_name;
if (!example_init)
{
/* Hijack a mutex for init'ing the storage engine */
pthread_mutex_lock(&LOCK_mysql_create_db);
if (!example_init)
{
example_init++;
VOID(pthread_mutex_init(&example_mutex,MY_MUTEX_INIT_FAST));
(void) hash_init(&example_open_tables,system_charset_info,32,0,0,
(hash_get_key) example_get_key,0,0);
}
pthread_mutex_unlock(&LOCK_mysql_create_db);
}
pthread_mutex_lock(&example_mutex);
length=(uint) strlen(table_name);
if (!(share=(EXAMPLE_SHARE*) hash_search(&example_open_tables,
(byte*) table_name,
length)))
{
if (!(share=(EXAMPLE_SHARE *)
my_multi_malloc(MYF(MY_WME | MY_ZEROFILL),
&share, sizeof(*share),
&tmp_name, length+1,
NullS)))
{
pthread_mutex_unlock(&example_mutex);
return NULL;
}
share->use_count=0;
share->table_name_length=length;
share->table_name=tmp_name;
strmov(share->table_name,table_name);
if (my_hash_insert(&example_open_tables, (byte*) share))
goto error;
thr_lock_init(&share->lock);
pthread_mutex_init(&share->mutex,MY_MUTEX_INIT_FAST);
}
share->use_count++;
pthread_mutex_unlock(&example_mutex);
return share;
error2:
thr_lock_delete(&share->lock);
pthread_mutex_destroy(&share->mutex);
error:
pthread_mutex_unlock(&example_mutex);
my_free((gptr) share, MYF(0));
return NULL;
}
/*
Free lock controls.
*/
static int free_share(EXAMPLE_SHARE *share)
{
pthread_mutex_lock(&example_mutex);
if (!--share->use_count)
{
hash_delete(&example_open_tables, (byte*) share);
thr_lock_delete(&share->lock);
pthread_mutex_destroy(&share->mutex);
my_free((gptr) share, MYF(0));
}
pthread_mutex_unlock(&example_mutex);
return 0;
}
const char **ha_example::bas_ext() const
{ static const char *ext[]= { NullS }; return ext; }
int ha_example::open(const char *name, int mode, uint test_if_locked)
{
DBUG_ENTER("ha_example::open");
if (!(share = get_share(name, table)))
DBUG_RETURN(1);
thr_lock_data_init(&share->lock,&lock,NULL);
DBUG_RETURN(0);
}
int ha_example::close(void)
{
DBUG_ENTER("ha_example::close");
DBUG_RETURN(free_share(share));
}
int ha_example::write_row(byte * buf)
{
DBUG_ENTER("ha_example::write_row");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::update_row(const byte * old_data, byte * new_data)
{
DBUG_ENTER("ha_example::update_row");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::delete_row(const byte * buf)
{
DBUG_ENTER("ha_example::delete_row");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::index_read(byte * buf, const byte * key,
uint key_len __attribute__((unused)),
enum ha_rkey_function find_flag
__attribute__((unused)))
{
DBUG_ENTER("ha_example::index_read");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::index_read_idx(byte * buf, uint index, const byte * key,
uint key_len __attribute__((unused)),
enum ha_rkey_function find_flag
__attribute__((unused)))
{
DBUG_ENTER("ha_example::index_read_idx");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::index_next(byte * buf)
{
DBUG_ENTER("ha_example::index_next");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::index_prev(byte * buf)
{
DBUG_ENTER("ha_example::index_prev");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::index_first(byte * buf)
{
DBUG_ENTER("ha_example::index_first");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::index_last(byte * buf)
{
DBUG_ENTER("ha_example::index_last");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::rnd_init(bool scan)
{
DBUG_ENTER("ha_example::rnd_init");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::rnd_next(byte *buf)
{
DBUG_ENTER("ha_example::rnd_next");
DBUG_RETURN(HA_ERR_END_OF_FILE);
}
void ha_example::position(const byte *record)
{
DBUG_ENTER("ha_example::position");
DBUG_VOID_RETURN;
}
int ha_example::rnd_pos(byte * buf, byte *pos)
{
DBUG_ENTER("ha_example::rnd_pos");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
void ha_example::info(uint flag)
{
DBUG_ENTER("ha_example::info");
DBUG_VOID_RETURN;
}
int ha_example::extra(enum ha_extra_function operation)
{
DBUG_ENTER("ha_example::extra");
DBUG_RETURN(0);
}
int ha_example::reset(void)
{
DBUG_ENTER("ha_example::reset");
DBUG_RETURN(0);
}
int ha_example::delete_all_rows()
{
DBUG_ENTER("ha_example::delete_all_rows");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
int ha_example::external_lock(THD *thd, int lock_type)
{
DBUG_ENTER("ha_example::external_lock");
DBUG_RETURN(0);
}
THR_LOCK_DATA **ha_example::store_lock(THD *thd,
THR_LOCK_DATA **to,
enum thr_lock_type lock_type)
{
if (lock_type != TL_IGNORE && lock.type == TL_UNLOCK)
lock.type=lock_type;
*to++= &lock;
return to;
}
int ha_example::delete_table(const char *name)
{
DBUG_ENTER("ha_example::delete_table");
/* This is not implemented but we want someone to be able that it works. */
DBUG_RETURN(0);
}
int ha_example::rename_table(const char * from, const char * to)
{
DBUG_ENTER("ha_example::rename_table ");
DBUG_RETURN(HA_ERR_NOT_IMPLEMENTED);
}
ha_rows ha_example::records_in_range(int inx,
const byte *start_key,uint start_key_len,
enum ha_rkey_function start_search_flag,
const byte *end_key,uint end_key_len,
enum ha_rkey_function end_search_flag)
{
DBUG_ENTER("ha_example::records_in_range ");
DBUG_RETURN(records); // HA_ERR_NOT_IMPLEMENTED
}
int ha_example::create(const char *name, TABLE *table_arg, HA_CREATE_INFO *create_info)
{
DBUG_ENTER("ha_example::create");
/* This is not implemented but we want someone to be able that it works. */
DBUG_RETURN(0);
}
#endif /* HAVE_EXAMPLE_DB */