/**
* Important: YOU HAVE TO make sure $tables and $where_conds don't contain
* unescaped user-supplied data!
*/
public static function get_set($tables, $joins, $where_conds, $min_store, $ref_max_age)
{
# Compute the "params hash".
$params_hash = md5(serialize(array($tables, $joins, $where_conds)));
# Check if there exists an entry for this hash, which also meets the
# given freshness criteria.
list($set_id, $date_created, $expires) = self::find_param_set($params_hash, $ref_max_age);
if ($set_id === null) {
# To avoid generating the same results by multiple threads at once
# (the "tile" method uses the "save" method, so the problem is
# quite real!), we will acquire a write-lock here.
$lock = OkapiLock::get("search-results-writer");
$lock->acquire();
try {
# Make sure we were the first to acquire the lock.
list($set_id, $date_created, $expires) = self::find_param_set($params_hash, $ref_max_age);
if ($set_id === null) {
# We are in the first thread which have acquired the lock.
# We will proceed with result-set creation. Other threads
# will be waiting until we finish.
Db::execute("\n insert into okapi_search_sets (params_hash, date_created, expires)\n values (\n 'processing in progress',\n now(),\n date_add(now(), interval '" . mysql_real_escape_string($min_store + 60) . "' second)\n )\n ");
$set_id = Db::last_insert_id();
$date_created = time();
$expires = $date_created + $min_store + 60;
Db::execute("\n insert into okapi_search_results (set_id, cache_id)\n select distinct\n '" . mysql_real_escape_string($set_id) . "',\n caches.cache_id\n from\n " . implode(", ", $tables) . "\n " . implode(" ", $joins) . "\n where (" . implode(") and (", $where_conds) . ")\n ");
# Lock barrier, to make sure the data is visible by other
# sessions. See http://bugs.mysql.com/bug.php?id=36618
Db::execute("lock table okapi_search_results write");
Db::execute("unlock tables");
Db::execute("\n update okapi_search_sets\n set params_hash = '" . mysql_real_escape_string($params_hash) . "'\n where id = '" . mysql_real_escape_string($set_id) . "'\n ");
} else {
# Some other thread acquired the lock before us and it has
# generated the result set. We don't need to do anything.
}
$lock->release();
} catch (Exception $e) {
# SQL error? Make sure the lock is released and rethrow.
$lock->release();
throw $e;
}
}
# If we got an old set, we may need to expand its lifetime in order to
# meet user's "min_store" criterium.
if (time() + $min_store > $expires) {
Db::execute("\n update okapi_search_sets\n set expires = date_add(now(), interval '" . mysql_real_escape_string($min_store + 60) . "' second)\n where id = '" . mysql_real_escape_string($set_id) . "'\n ");
}
return array('set_id' => "{$set_id}", 'generated_at' => date('c', $date_created), 'expires' => date('c', $expires));
}
/**
* Reset the schedule of a specified cronjob. This will force the job to
* run on nearest occasion (but not NOW).
*/
public static function reset_job_schedule($job_name)
{
$thejob = null;
foreach (self::get_enabled_cronjobs() as $tmp) {
if ($tmp->get_name() == $job_name || $tmp->get_name() == "okapi\\cronjobs\\" . $job_name) {
$thejob = $tmp;
}
}
if ($thejob == null) {
throw new Exception("Could not reset schedule for job {$job_name}. {$jon_name} not found.");
}
# We have to acquire lock on the schedule. This might take some time if cron-5 jobs are
# currently being run.
$type = $thejob->get_type();
$lock = OkapiLock::get('cronjobs-' . $type);
$lock->acquire();
$schedule = Cache::get("cron_schedule");
if ($schedule != null) {
if (isset($schedule[$thejob->get_name()])) {
unset($schedule[$thejob->get_name()]);
}
Cache::set("cron_schedule", $schedule, 30 * 86400);
}
$lock->release();
}
private static function ver68()
{
# Once again, remove unused locks.
for ($z = 0; $z <= 21; $z++) {
foreach (array("", "-0", "-1") as $suffix) {
$lockname = "tile-{$z}{$suffix}";
if (OkapiLock::exists($lockname)) {
OkapiLock::get($lockname)->remove();
}
}
}
}
