/**
* Determine if the cache folder is writeable
*
* @param string $folder The folder or NULL to use the static property CacheFolder (default: NULL)
* @return boolean Writeable?
*/
public static function IsCacheFolderWriteAble($folder = null)
{
if (!is_null(self::$CacheFolderWriteAble)) {
return self::$CacheFolderWriteAble;
}
if (is_null($folder)) {
$folder = self::$CacheFolder;
}
if (is_null($folder)) {
self::$CacheFolderWriteAble = false;
return false;
}
if (!is_dir($folder)) {
self::Debug('Invalid cache folder (not a directory?)');
self::$CacheFolderWriteAble = false;
return;
}
$file = uniqid();
while (file_exists($folder . '/' . $file)) {
$file = uniqid();
}
$file = $folder . '/' . $file;
$temp = uniqid();
if (file_put_contents($file, $temp) === false) {
self::$CacheFolderWriteAble = false;
return false;
}
$res = file_get_contents($file) === $temp;
unlink($file);
self::$CacheFolderWriteAble = $res;
return $res;
}
