wiki.techinc.nl/includes/utils/Cdb.php
umherirrender 7c6a25856c Add missing @return to function docs
Change-Id: I45b9d02f94ecc58372268ec5e6a0b572a0b7e2a9
2014-08-23 23:14:57 +02:00

163 lines
3.6 KiB
PHP

<?php
/**
* Native CDB file reader and writer.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
/**
* Read from a CDB file.
* Native and pure PHP implementations are provided.
* http://cr.yp.to/cdb.html
*/
abstract class CdbReader {
/**
* The file handle
*/
protected $handle;
/**
* Open a file and return a subclass instance
*
* @param string $fileName
*
* @return CdbReader
*/
public static function open( $fileName ) {
return self::haveExtension() ?
new CdbReaderDBA( $fileName ) :
new CdbReaderPHP( $fileName );
}
/**
* Returns true if the native extension is available
*
* @return bool
*/
public static function haveExtension() {
if ( !function_exists( 'dba_handlers' ) ) {
return false;
}
$handlers = dba_handlers();
if ( !in_array( 'cdb', $handlers ) || !in_array( 'cdb_make', $handlers ) ) {
return false;
}
return true;
}
/**
* Create the object and open the file
*
* @param string $fileName
*/
abstract public function __construct( $fileName );
/**
* Close the file. Optional, you can just let the variable go out of scope.
*/
abstract public function close();
/**
* Get a value with a given key. Only string values are supported.
*
* @param string $key
*/
abstract public function get( $key );
}
/**
* Write to a CDB file.
* Native and pure PHP implementations are provided.
*/
abstract class CdbWriter {
/**
* The file handle
*/
protected $handle;
/**
* File we'll be writing to when we're done
* @var string
*/
protected $realFileName;
/**
* File we write to temporarily until we're done
* @var string
*/
protected $tmpFileName;
/**
* Open a writer and return a subclass instance.
* The user must have write access to the directory, for temporary file creation.
*
* @param string $fileName
*
* @return CdbWriterDBA|CdbWriterPHP
*/
public static function open( $fileName ) {
return CdbReader::haveExtension() ?
new CdbWriterDBA( $fileName ) :
new CdbWriterPHP( $fileName );
}
/**
* Create the object and open the file
*
* @param string $fileName
*/
abstract public function __construct( $fileName );
/**
* Set a key to a given value. The value will be converted to string.
* @param string $key
* @param string $value
*/
abstract public function set( $key, $value );
/**
* Close the writer object. You should call this function before the object
* goes out of scope, to write out the final hashtables.
*/
abstract public function close();
/**
* If the object goes out of scope, close it for sanity
*/
public function __destruct() {
if ( isset( $this->handle ) ) {
$this->close();
}
}
/**
* Are we running on Windows?
* @return bool
*/
protected function isWindows() {
return substr( php_uname(), 0, 7 ) == 'Windows';
}
}
/**
* Exception for Cdb errors.
* This explicitly doesn't subclass MWException to encourage reuse.
*/
class CdbException extends Exception {
}