+++ /dev/null
-<?php
-/**
- * Object caching using DBA backend.
- *
- * 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
- * @ingroup Cache
- */
-
-/**
- * Cache that uses DBA as a backend.
- * Slow due to the need to constantly open and close the file to avoid holding
- * writer locks. Intended for development use only, as a memcached workalike
- * for systems that don't have it.
- *
- * On construction you can pass array( 'dir' => '/some/path' ); as a parameter
- * to override the default DBA files directory (wfTempDir()).
- *
- * @ingroup Cache
- */
-class DBABagOStuff extends BagOStuff {
- var $mHandler, $mFile, $mReader, $mWriter, $mDisabled;
-
- /**
- * @param $params array
- */
- public function __construct( $params ) {
- global $wgDBAhandler;
-
- if ( !isset( $params['dir'] ) ) {
- $params['dir'] = wfTempDir();
- }
-
- $this->mFile = $params['dir'] . '/mw-cache-' . wfWikiID() . '.db';
- wfDebug( __CLASS__ . ": using cache file {$this->mFile}\n" );
- $this->mHandler = $wgDBAhandler;
- }
-
- /**
- * Encode value and expiry for storage
- * @param $value
- * @param $expiry
- *
- * @return string
- */
- protected function encode( $value, $expiry ) {
- # Convert to absolute time
- $expiry = $this->convertExpiry( $expiry );
-
- return sprintf( '%010u', intval( $expiry ) ) . ' ' . serialize( $value );
- }
-
- /**
- * @param $blob string
- * @return array list containing value first and expiry second
- */
- protected function decode( $blob ) {
- if ( !is_string( $blob ) ) {
- return array( false, 0 );
- } else {
- return array(
- unserialize( substr( $blob, 11 ) ),
- intval( substr( $blob, 0, 10 ) )
- );
- }
- }
-
- /**
- * @return resource
- */
- protected function getReader() {
- if ( file_exists( $this->mFile ) ) {
- $handle = dba_open( $this->mFile, 'rl', $this->mHandler );
- } else {
- $handle = $this->getWriter();
- }
-
- if ( !$handle ) {
- wfDebug( "Unable to open DBA cache file {$this->mFile}\n" );
- }
-
- return $handle;
- }
-
- /**
- * @return resource
- */
- protected function getWriter() {
- $handle = dba_open( $this->mFile, 'cl', $this->mHandler );
-
- if ( !$handle ) {
- wfDebug( "Unable to open DBA cache file {$this->mFile}\n" );
- }
-
- return $handle;
- }
-
- /**
- * @param $key string
- * @param $casToken[optional] mixed
- * @return mixed
- */
- public function get( $key, &$casToken = null ) {
- wfProfileIn( __METHOD__ );
- wfDebug( __METHOD__ . "($key)\n" );
-
- $handle = $this->getReader();
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- $val = dba_fetch( $key, $handle );
- $casToken = $val;
- list( $val, $expiry ) = $this->decode( $val );
-
- # Must close ASAP because locks are held
- dba_close( $handle );
-
- if ( $val !== false && $expiry && $expiry < time() ) {
- # Key is expired, delete it
- $handle = $this->getWriter();
- dba_delete( $key, $handle );
- dba_close( $handle );
- wfDebug( __METHOD__ . ": $key expired\n" );
- $val = false;
- }
-
- wfProfileOut( __METHOD__ );
-
- return $val;
- }
-
- /**
- * @param $key string
- * @param $value mixed
- * @param $exptime int
- * @return bool
- */
- public function set( $key, $value, $exptime = 0 ) {
- wfProfileIn( __METHOD__ );
- wfDebug( __METHOD__ . "($key)\n" );
-
- $blob = $this->encode( $value, $exptime );
-
- $handle = $this->getWriter();
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- $ret = dba_replace( $key, $blob, $handle );
- dba_close( $handle );
-
- wfProfileOut( __METHOD__ );
- return $ret;
- }
-
- /**
- * @param $casToken mixed
- * @param $key string
- * @param $value mixed
- * @param $exptime int
- * @return bool
- */
- public function cas( $casToken, $key, $value, $exptime = 0 ) {
- wfProfileIn( __METHOD__ );
- wfDebug( __METHOD__ . "($key)\n" );
-
- $blob = $this->encode( $value, $exptime );
-
- $handle = $this->getWriter();
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- // DBA is locked to any other write connection, so we can safely
- // compare the current & previous value before saving new value
- $val = dba_fetch( $key, $handle );
- if ( $casToken !== $val ) {
- dba_close( $handle );
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- $ret = dba_replace( $key, $blob, $handle );
- dba_close( $handle );
-
- wfProfileOut( __METHOD__ );
- return $ret;
- }
-
- /**
- * @param $key string
- * @param $time int
- * @return bool
- */
- public function delete( $key, $time = 0 ) {
- wfProfileIn( __METHOD__ );
- wfDebug( __METHOD__ . "($key)\n" );
-
- $handle = $this->getWriter();
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- $ret = !dba_exists( $key, $handle ) || dba_delete( $key, $handle );
- dba_close( $handle );
-
- wfProfileOut( __METHOD__ );
- return $ret;
- }
-
- /**
- * @param $key string
- * @param $value mixed
- * @param $exptime int
- * @return bool
- */
- public function add( $key, $value, $exptime = 0 ) {
- wfProfileIn( __METHOD__ );
-
- $blob = $this->encode( $value, $exptime );
-
- $handle = $this->getWriter();
-
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- $ret = dba_insert( $key, $blob, $handle );
-
- # Insert failed, check to see if it failed due to an expired key
- if ( !$ret ) {
- list( , $expiry ) = $this->decode( dba_fetch( $key, $handle ) );
-
- if ( $expiry && $expiry < time() ) {
- # Yes expired, delete and try again
- dba_delete( $key, $handle );
- $ret = dba_insert( $key, $blob, $handle );
- # This time if it failed then it will be handled by the caller like any other race
- }
- }
-
- dba_close( $handle );
-
- wfProfileOut( __METHOD__ );
- return $ret;
- }
-
- /**
- * @param $key string
- * @param $step integer
- * @return integer|bool
- */
- public function incr( $key, $step = 1 ) {
- wfProfileIn( __METHOD__ );
-
- $handle = $this->getWriter();
-
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- list( $value, $expiry ) = $this->decode( dba_fetch( $key, $handle ) );
- if ( $value !== false ) {
- if ( $expiry && $expiry < time() ) {
- # Key is expired, delete it
- dba_delete( $key, $handle );
- wfDebug( __METHOD__ . ": $key expired\n" );
- $value = false;
- } else {
- $value += $step;
- $blob = $this->encode( $value, $expiry );
-
- $ret = dba_replace( $key, $blob, $handle );
- $value = $ret ? $value : false;
- }
- }
-
- dba_close( $handle );
-
- wfProfileOut( __METHOD__ );
-
- return ( $value === false ) ? false : (int)$value;
- }
-}
dépôts / lhc / web / wiklou.git / commitdiff