/**
* Creates an instance of the given update class.
*
* @access public
* @param string $driver The type of PPU to create.
* @param string $packageName The package to update.
* @param string $channel The channel the package resides on.
* @return object An instance of type PEAR_PackageUpdate_$driver
* @since 0.4.0a1
* @throws PEAR_PACKAGEUPDATE_ERROR_NONEXISTENTDRIVER
*/
function &factory($driver, $packageName, $channel)
{
$class = 'PEAR_PackageUpdate_' . $driver;
// Attempt to include a custom version of the named class, but don't treat
// a failure as fatal. The caller may have already included their own
// version of the named class.
if (!class_exists($class)) {
// Try to include the driver.
$file = 'PEAR/PackageUpdate/' . $driver . '.php';
if (!PEAR_PackageUpdate::isIncludable($file)) {
PEAR_ErrorStack::staticPush('PEAR_PackageUpdate', PEAR_PACKAGEUPDATE_ERROR_NONEXISTENTDRIVER, null, array('drivername' => $driver), $GLOBALS['_PEAR_PACKAGEUPDATE_ERRORS'][PEAR_PACKAGEUPDATE_ERROR_NONEXISTENTDRIVER]);
// Must assign a variable to avoid notice about references.
$false = false;
return $false;
}
include_once $file;
}
// See if the class exists now.
if (!class_exists($class)) {
// Must assign a variable to avoid notice about references.
$false = false;
return $false;
}
// Try to instantiate the class.
$instance =& new $class($packageName, $channel);
return $instance;
}
