sanitize_file_name

Source code

function sanitize_file_name( $filename ) {

	$filename_raw = $filename;

	$special_chars = array("?", "[", "]", "/", "\\", "=", "<", ">", ":", ";", ",", "'", "\"", "&", "$", "#", "*", "(", ")", "|", "~", "`", "!", "{", "}", chr(0));

	$special_chars = apply_filters('sanitize_file_name_chars', $special_chars, $filename_raw);

	$filename = str_replace($special_chars, '', $filename);

	$filename = preg_replace('/[\s-]+/', '-', $filename);

	$filename = trim($filename, '.-_');



	// Split the filename into a base and extension[s]

	$parts = explode('.', $filename);



	// Return if only one extension

	if ( count($parts) <= 2 )

		return apply_filters('sanitize_file_name', $filename, $filename_raw);



	// Process multiple extensions

	$filename = array_shift($parts);

	$extension = array_pop($parts);

	$mimes = get_allowed_mime_types();



	// Loop over any intermediate extensions.  Munge them with a trailing underscore if they are a 2 - 5 character

	// long alpha string not in the extension whitelist.

	foreach ( (array) $parts as $part) {

		$filename .= '.' . $part;



		if ( preg_match("/^[a-zA-Z]{2,5}\d?$/", $part) ) {

			$allowed = false;

			foreach ( $mimes as $ext_preg => $mime_match ) {

				$ext_preg = '!^(' . $ext_preg . ')$!i';

				if ( preg_match( $ext_preg, $part ) ) {

					$allowed = true;

					break;

				}

			}

			if ( !$allowed )

				$filename .= '_';

		}

	}

	$filename .= '.' . $extension;



	return apply_filters('sanitize_file_name', $filename, $filename_raw);

}