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/* Copyright (C) 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#include <drizzled/server_includes.h>
#include <drizzled/gettext.h>
#include <drizzled/error.h>
#include <drizzled/plugin/scheduler.h>
#include <drizzled/connect.h>
#include <drizzled/sql_parse.h>
#include <drizzled/session.h>
#include <drizzled/connect.h>
#include <string>
using namespace std;
class Single_thread_scheduler : public Scheduler
{
public:
Single_thread_scheduler()
: Scheduler(1) {}
virtual bool init_new_connection_thread(void) {return 0;}
/*
Simple scheduler that use the main thread to handle the request
NOTES
This is only used for debugging, when starting mysqld with
--thread-handling=no-threads or --one-thread
When we enter this function, LOCK_thread_count is held!
*/
virtual bool add_connection(Session *session)
{
handle_one_connection((void*) session);
return false;
}
/*
End connection, in case when we are using 'no-threads'
*/
virtual bool end_thread(Session *session, bool)
{
unlink_session(session); /* locks LOCK_thread_count and deletes session */
return true; // Abort handle_one_connection
}
virtual uint32_t count(void)
{
return 0;
}
};
class SingleThreadFactory : public SchedulerFactory
{
public:
SingleThreadFactory() : SchedulerFactory("single_thread") {}
~SingleThreadFactory() { if (scheduler != NULL) delete scheduler; }
Scheduler *operator() ()
{
if (scheduler == NULL)
scheduler= new Single_thread_scheduler();
return scheduler;
}
};
SingleThreadFactory *factory= NULL;
static int init(PluginRegistry ®istry)
{
factory= new SingleThreadFactory();
registry.add(factory);
return 0;
}
static int deinit(PluginRegistry ®istry)
{
if (factory)
{
registry.remove(factory);
delete factory;
}
return 0;
}
static struct st_mysql_sys_var* system_variables[]= {
NULL
};
drizzle_declare_plugin(single_thread)
{
"single_thread",
"0.1",
"Brian Aker",
"Single Thread Scheduler",
PLUGIN_LICENSE_GPL,
init, /* Plugin Init */
deinit, /* Plugin Deinit */
NULL, /* status variables */
system_variables, /* system variables */
NULL /* config options */
}
drizzle_declare_plugin_end;
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