/*
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
*/

/*
* Create table for quota data with the following statement:
*
* CREATE TABLE `Quota` (`Db` CHAR(64) NOT NULL,
* `Limit` BIGINT NOT NULL,
* `Exceeded` ENUM('Y','N') DEFAULT 'N' NOT NULL,
* PRIMARY KEY (`Db`), UNIQUE (`Db`));
*
* The field 'db' stores the information for which database
* you want to limit the size.
* The field 'limit' is the size limit in bytes.
* The field 'exceeded' is only used internally and must be
* initialized with 'N'.
*/

/*
* Settings
*/

$mysql_host = 'localhost';
$mysql_user = 'root'; // Do NOT change, root-access is required
$mysql_pass = '';
$mysql_db = 'quotadb'; // Not the DB to check, but the db with the quota table
$mysql_table = 'quota';

/*
* Do NOT change anything below
*/

$debug = 0;

// Connect to MySQL Server

if (!mysql_connect($mysql_host, $mysql_user, $mysql_pass))
{
echo "Connection to MySQL-server failed!";
exit;
}

// Select database

if (!mysql_select_db($mysql_db))
{
echo "Selection of database $mysql_db failed!";
exit;
}

// Check quota for each entry in quota table

$sql = "SELECT * FROM $mysql_table;";
$result = mysql_query($sql);

while ($row = mysql_fetch_array($result))
{
$quota_db = $row['db'];
$quota_limit = $row['limit'];
$quota_exceeded = ($row['exceeded']=='Y') ? 1 : 0;

if ($debug)
echo "Checking quota for '$quota_db'...\n";

$qsql = "SHOW TABLE STATUS FROM $quota_db;";
$qresult = mysql_query($qsql);

if ($debug)
echo "SQL-query is \"$qsql\"\n";

$quota_size = 0;

while ($qrow = mysql_fetch_array($qresult))
{
if ($debug)
{ echo "Result of query:\n"; var_dump($qrow); }
$quota_size += $qrow['Data_length'] + $qrow['Index_length'];
}

if ($debug)
echo "Size is $quota_size bytes, limit is $quota_limit bytes\n";

if ($debug && $quota_exceeded)
echo "Quota is marked as exceeded.\n";
if ($debug && !$quota_exceeded)
echo "Quota is not marked as exceeded.\n";

if (($quota_size > $quota_limit) && !$quota_exceeded)
{
if ($debug)
echo "Locking database...\n";
// Save in quota table
$usql = "UPDATE $mysql_table SET exceeded='Y' WHERE db='$quota_db';";
mysql_query($usql);
if ($debug)
echo "Querying: $usql\n";
// Dismiss CREATE and INSERT privilege for database
mysql_select_db('mysql');
$usql = "UPDATE db SET Insert_priv='N', Create_priv='N' WHERE Db='$quota_db';";
mysql_query($usql);
if ($debug)
echo "Querying: $usql\n";
mysql_select_db($mysql_db);
}

if (($quota_size <= $quota_limit) && $quota_exceeded)
{
if ($debug)
echo "Unlocking database...\n";
// Save in quota table
$usql = "UPDATE $mysql_table SET exceeded='N' WHERE db='$quota_db';";
mysql_query($usql);
if ($debug)
echo "Querying: $usql\n";
// Grant CREATE and INSERT privilege for database
mysql_select_db('mysql');
$usql = "UPDATE db SET Insert_priv='Y', Create_priv='Y' WHERE Db='$quota_db';";
mysql_query($usql);
if ($debug)
echo "Querying: $usql\n";
mysql_select_db($mysql_db);
}
}