<?php
+
+require_once 'exceptions/IOException.php';
+
/**
- * Exception class thrown when a filesystem access failure happens
+ * Class FileUtils
+ *
+ * Utility class for file manipulation.
*/
-class IOException extends Exception
+class FileUtils
{
- private $path;
+ /**
+ * @var string
+ */
+ protected static $phpPrefix = '<?php /* ';
/**
- * Construct a new IOException
+ * @var string
+ */
+ protected static $phpSuffix = ' */ ?>';
+
+ /**
+ * Write data into a file (Shaarli database format).
+ * The data is stored in a PHP file, as a comment, in compressed base64 format.
+ *
+ * The file will be created if it doesn't exist.
+ *
+ * @param string $file File path.
+ * @param mixed $content Content to write.
*
- * @param string $path path to the ressource that cannot be accessed
+ * @return int|bool Number of bytes written or false if it fails.
+ *
+ * @throws IOException The destination file can't be written.
*/
- public function __construct($path)
+ public static function writeFlatDB($file, $content)
{
- $this->path = $path;
- $this->message = 'Error accessing '.$this->path;
+ if (is_file($file) && !is_writeable($file)) {
+ // The datastore exists but is not writeable
+ throw new IOException($file);
+ } else if (!is_file($file) && !is_writeable(dirname($file))) {
+ // The datastore does not exist and its parent directory is not writeable
+ throw new IOException(dirname($file));
+ }
+
+ return file_put_contents(
+ $file,
+ self::$phpPrefix.base64_encode(gzdeflate(serialize($content))).self::$phpSuffix
+ );
+ }
+
+ /**
+ * Read data from a file containing Shaarli database format content.
+ *
+ * If the file isn't readable or doesn't exist, default data will be returned.
+ *
+ * @param string $file File path.
+ * @param mixed $default The default value to return if the file isn't readable.
+ *
+ * @return mixed The content unserialized, or default if the file isn't readable, or false if it fails.
+ */
+ public static function readFlatDB($file, $default = null)
+ {
+ // Note that gzinflate is faster than gzuncompress.
+ // See: http://www.php.net/manual/en/function.gzdeflate.php#96439
+ if (! is_readable($file)) {
+ return $default;
+ }
+
+ $data = file_get_contents($file);
+ if ($data == '') {
+ return $default;
+ }
+
+ return unserialize(
+ gzinflate(
+ base64_decode(
+ substr($data, strlen(self::$phpPrefix), -strlen(self::$phpSuffix))
+ )
+ )
+ );
}
}