function &_singleton(&$caller)
{
global $CFG;
static $instances;
static $self;
$plugin = NULL;
$prefix = NULL;
$name = NULL;
$params = NULL;
$filefilter = NULL;
$public = false;
$shared = false;
$synchronize = false;
$id = NULL;
if ($caller != NULL) {
$plugin = $caller->plugin;
$prefix = $caller->prefix;
$name = $caller->name;
$params = $caller->params;
$filefilter = $caller->filefilter;
$public = $caller->public;
$shared = $caller->shared;
$synchronize = $caller->synchronize;
$id = $caller->id;
} else {
$caller = new object();
}
if ($plugin == NULL && $prefix == NULL) {
if (!is_object($self)) {
$self = new podcaster_repositoryimpl('NULL', 'NULL');
}
return $self;
}
if (!is_array($instances)) {
$instances = array();
}
if (!array_key_exists($prefix, $instances)) {
include_once $CFG->dirroot . '/mod/podcaster/repository/' . $plugin . '/lib.php';
$classname = $plugin . '_repository';
if (!class_exists($classname)) {
error('Unable to load plugin "' . $plugin . '" (required class: ' . $classname . ', expected in repository/' . $plugin . '/lib.php)');
}
$instances[$prefix] = NULL;
$instances[$prefix] = new $classname($plugin, $prefix);
if (is_object($instances[$prefix])) {
foreach (explode("\r", $params) as $p) {
if (($lp = strpos($p, '=')) !== false) {
$lvalue = trim(substr($p, 0, $lp));
$rvalue = trim(substr($p, $lp + 1));
$instances[$prefix]->params[$lvalue] = $rvalue;
}
}
$instances[$prefix]->id = $id;
$instances[$prefix]->name = $name;
$instances[$prefix]->filefilter = $filefilter;
$instances[$prefix]->prefix = $prefix;
$instances[$prefix]->public = $public;
$instances[$prefix]->shared = $shared;
$instances[$prefix]->synchronize = $synchronize;
$allowedTypes = explode(',', $filefilter);
$instances[$prefix]->allowed_types = array();
foreach ($allowedTypes as $t) {
$instances[$prefix]->allowed_types[strtolower(trim($t))] = true;
}
$class = get_class($instances[$prefix]);
stream_wrapper_register($prefix, $class);
// we need the reverse mapping too
podcaster_repositoryimpl::add_plugin($plugin, $prefix);
}
}
return $instances[$prefix];
}
