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/* - 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
*/
#include "config.h"
#include <plugin/function_engine/cursor.h>
#include <drizzled/session.h>
#include "drizzled/internal/my_sys.h"
#include <unistd.h>
#include <fcntl.h>
#include <string>
using namespace std;
using namespace drizzled;
/*****************************************************************************
** Data Function tables
*****************************************************************************/
FunctionCursor::FunctionCursor(plugin::StorageEngine &engine_arg,
TableShare &table_arg) :
Cursor(engine_arg, table_arg),
estimate_of_rows(100), // Completely fabricated, I used to use the value 2.
rows_returned(0)
{}
int FunctionCursor::open(const char *name, int, uint32_t)
{
tool= static_cast<Function *>(engine)->getFunction(name);
// assert(tool);
record_id= 0;
if (not tool)
return HA_ERR_NO_SUCH_TABLE;
return 0;
}
int FunctionCursor::close(void)
{
tool= NULL;
wipeCache();
return 0;
}
int FunctionCursor::doStartTableScan(bool)
{
rows_returned= 0;
generator= tool->generator(table->getFields());
return 0;
}
int FunctionCursor::rnd_next(unsigned char *)
{
bool more_rows;
ha_statistic_increment(&system_status_var::ha_read_rnd_next_count);
/* Fix bug in the debug logic for field */
for (Field **field= table->getFields() ; *field ; field++)
{
(*field)->setWriteSet();
}
more_rows= generator->sub_populate(table->getShare()->sizeFields());
if (more_rows)
{
return 0;
}
else
{
delete generator;
generator= NULL;
}
rows_returned++;
return more_rows ? 0 : HA_ERR_END_OF_FILE;
}
void FunctionCursor::position(const unsigned char *record)
{
if (row_cache.size() <= record_id * table->getShare()->getRecordLength())
{
row_cache.resize(row_cache.size() + table->getShare()->getRecordLength() * 100); // Hardwired at adding an additional 100 rows of storage
}
memcpy(&row_cache[record_id * table->getShare()->getRecordLength()], record, table->getShare()->getRecordLength());
internal::my_store_ptr(ref, ref_length, record_id);
record_id++;
}
void FunctionCursor::wipeCache()
{
if (rows_returned > estimate_of_rows)
estimate_of_rows= rows_returned;
row_cache.clear();
record_id= 0;
}
int FunctionCursor::extra(enum ha_extra_function operation)
{
switch (operation)
{
case drizzled::HA_EXTRA_CACHE:
break;
case drizzled::HA_EXTRA_NO_CACHE:
break;
case drizzled::HA_EXTRA_RESET_STATE:
wipeCache();
break;
default:
break;
}
return 0;
}
int FunctionCursor::doEndTableScan()
{
delete generator; // Do this in case of an early exit from rnd_next()
return 0;
}
int FunctionCursor::rnd_pos(unsigned char *buf, unsigned char *pos)
{
ha_statistic_increment(&system_status_var::ha_read_rnd_count);
size_t position_id= (size_t)internal::my_get_ptr(pos, ref_length);
assert(position_id * table->getShare()->getRecordLength() < row_cache.size());
memcpy(buf, &row_cache[position_id * table->getShare()->getRecordLength()], table->getShare()->getRecordLength());
return 0;
}
int FunctionCursor::info(uint32_t flag)
{
memset(&stats, 0, sizeof(stats));
if (flag & HA_STATUS_AUTO)
stats.auto_increment_value= 1;
stats.records= estimate_of_rows;
return 0;
}
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