+++ /dev/null
-<?php
-/**
- * Classes to cache objects in PHP accelerators, SQL database or DBA files
- *
- * Copyright © 2003-2004 Brion Vibber <brion@pobox.com>
- * http://www.mediawiki.org/
- *
- * 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
- */
-
-/**
- * @defgroup Cache Cache
- */
-
-/**
- * interface is intended to be more or less compatible with
- * the PHP memcached client.
- *
- * backends for local hash array and SQL table included:
- * <code>
- * $bag = new HashBagOStuff();
- * $bag = new SqlBagOStuff(); # connect to db first
- * </code>
- *
- * @ingroup Cache
- */
-abstract class BagOStuff {
- var $debugMode = false;
-
- public function set_debug( $bool ) {
- $this->debugMode = $bool;
- }
-
- /* *** THE GUTS OF THE OPERATION *** */
- /* Override these with functional things in subclasses */
-
- /**
- * Get an item with the given key. Returns false if it does not exist.
- * @param $key string
- */
- abstract public function get( $key );
-
- /**
- * Set an item.
- * @param $key string
- * @param $value mixed
- * @param $exptime int Either an interval in seconds or a unix timestamp for expiry
- */
- abstract public function set( $key, $value, $exptime = 0 );
-
- /*
- * Delete an item.
- * @param $key string
- * @param $time int Amount of time to delay the operation (mostly memcached-specific)
- */
- abstract public function delete( $key, $time = 0 );
-
- public function lock( $key, $timeout = 0 ) {
- /* stub */
- return true;
- }
-
- public function unlock( $key ) {
- /* stub */
- return true;
- }
-
- public function keys() {
- /* stub */
- return array();
- }
-
- /* *** Emulated functions *** */
- /* Better performance can likely be got with custom written versions */
- public function get_multi( $keys ) {
- $out = array();
-
- foreach ( $keys as $key ) {
- $out[$key] = $this->get( $key );
- }
-
- return $out;
- }
-
- public function set_multi( $hash, $exptime = 0 ) {
- foreach ( $hash as $key => $value ) {
- $this->set( $key, $value, $exptime );
- }
- }
-
- public function add( $key, $value, $exptime = 0 ) {
- if ( !$this->get( $key ) ) {
- $this->set( $key, $value, $exptime );
-
- return true;
- }
- }
-
- public function add_multi( $hash, $exptime = 0 ) {
- foreach ( $hash as $key => $value ) {
- $this->add( $key, $value, $exptime );
- }
- }
-
- public function delete_multi( $keys, $time = 0 ) {
- foreach ( $keys as $key ) {
- $this->delete( $key, $time );
- }
- }
-
- public function replace( $key, $value, $exptime = 0 ) {
- if ( $this->get( $key ) !== false ) {
- $this->set( $key, $value, $exptime );
- }
- }
-
- /**
- * @param $key String: Key to increase
- * @param $value Integer: Value to add to $key (Default 1)
- * @return null if lock is not possible else $key value increased by $value
- */
- public function incr( $key, $value = 1 ) {
- if ( !$this->lock( $key ) ) {
- return null;
- }
-
- $value = intval( $value );
-
- if ( ( $n = $this->get( $key ) ) !== false ) {
- $n += $value;
- $this->set( $key, $n ); // exptime?
- }
- $this->unlock( $key );
-
- return $n;
- }
-
- public function decr( $key, $value = 1 ) {
- return $this->incr( $key, - $value );
- }
-
- public function debug( $text ) {
- if ( $this->debugMode ) {
- wfDebug( "BagOStuff debug: $text\n" );
- }
- }
-
- /**
- * Convert an optionally relative time to an absolute time
- */
- protected function convertExpiry( $exptime ) {
- if ( ( $exptime != 0 ) && ( $exptime < 86400 * 3650 /* 10 years */ ) ) {
- return time() + $exptime;
- } else {
- return $exptime;
- }
- }
-}
-
-/**
- * Functional versions!
- * This is a test of the interface, mainly. It stores things in an associative
- * array, which is not going to persist between program runs.
- *
- * @ingroup Cache
- */
-class HashBagOStuff extends BagOStuff {
- var $bag;
-
- function __construct() {
- $this->bag = array();
- }
-
- protected function expire( $key ) {
- $et = $this->bag[$key][1];
-
- if ( ( $et == 0 ) || ( $et > time() ) ) {
- return false;
- }
-
- $this->delete( $key );
-
- return true;
- }
-
- function get( $key ) {
- if ( !isset( $this->bag[$key] ) ) {
- return false;
- }
-
- if ( $this->expire( $key ) ) {
- return false;
- }
-
- return $this->bag[$key][0];
- }
-
- function set( $key, $value, $exptime = 0 ) {
- $this->bag[$key] = array( $value, $this->convertExpiry( $exptime ) );
- }
-
- function delete( $key, $time = 0 ) {
- if ( !isset( $this->bag[$key] ) ) {
- return false;
- }
-
- unset( $this->bag[$key] );
-
- return true;
- }
-
- function keys() {
- return array_keys( $this->bag );
- }
-}
-
-/**
- * Class to store objects in the database
- *
- * @ingroup Cache
- */
-class SqlBagOStuff extends BagOStuff {
- var $lb, $db;
- var $lastExpireAll = 0;
-
- protected function getDB() {
- global $wgDBtype;
-
- if ( !isset( $this->db ) ) {
- /* We must keep a separate connection to MySQL in order to avoid deadlocks
- * However, SQLite has an opposite behaviour.
- * @todo Investigate behaviour for other databases
- */
- if ( $wgDBtype == 'sqlite' ) {
- $this->db = wfGetDB( DB_MASTER );
- } else {
- $this->lb = wfGetLBFactory()->newMainLB();
- $this->db = $this->lb->getConnection( DB_MASTER );
- $this->db->clearFlag( DBO_TRX );
- }
- }
-
- return $this->db;
- }
-
- public function get( $key ) {
- # expire old entries if any
- $this->garbageCollect();
- $db = $this->getDB();
- $row = $db->selectRow( 'objectcache', array( 'value', 'exptime' ),
- array( 'keyname' => $key ), __METHOD__ );
-
- if ( !$row ) {
- $this->debug( 'get: no matching rows' );
- return false;
- }
-
- $this->debug( "get: retrieved data; expiry time is " . $row->exptime );
-
- if ( $this->isExpired( $row->exptime ) ) {
- $this->debug( "get: key has expired, deleting" );
- try {
- $db->begin();
- # Put the expiry time in the WHERE condition to avoid deleting a
- # newly-inserted value
- $db->delete( 'objectcache',
- array(
- 'keyname' => $key,
- 'exptime' => $row->exptime
- ), __METHOD__ );
- $db->commit();
- } catch ( DBQueryError $e ) {
- $this->handleWriteError( $e );
- }
-
- return false;
- }
-
- return $this->unserialize( $db->decodeBlob( $row->value ) );
- }
-
- public function set( $key, $value, $exptime = 0 ) {
- $db = $this->getDB();
- $exptime = intval( $exptime );
-
- if ( $exptime < 0 ) {
- $exptime = 0;
- }
-
- if ( $exptime == 0 ) {
- $encExpiry = $this->getMaxDateTime();
- } else {
- if ( $exptime < 3.16e8 ) { # ~10 years
- $exptime += time();
- }
-
- $encExpiry = $db->timestamp( $exptime );
- }
- try {
- $db->begin();
- // (bug 24425) use a replace if the db supports it instead of
- // delete/insert to avoid clashes with conflicting keynames
- $db->replace( 'objectcache', array( 'keyname' ),
- array(
- 'keyname' => $key,
- 'value' => $db->encodeBlob( $this->serialize( $value ) ),
- 'exptime' => $encExpiry
- ), __METHOD__ );
- $db->commit();
- } catch ( DBQueryError $e ) {
- $this->handleWriteError( $e );
-
- return false;
- }
-
- return true;
- }
-
- public function delete( $key, $time = 0 ) {
- $db = $this->getDB();
-
- try {
- $db->begin();
- $db->delete( 'objectcache', array( 'keyname' => $key ), __METHOD__ );
- $db->commit();
- } catch ( DBQueryError $e ) {
- $this->handleWriteError( $e );
-
- return false;
- }
-
- return true;
- }
-
- public function incr( $key, $step = 1 ) {
- $db = $this->getDB();
- $step = intval( $step );
-
- try {
- $db->begin();
- $row = $db->selectRow( 'objectcache', array( 'value', 'exptime' ),
- array( 'keyname' => $key ), __METHOD__, array( 'FOR UPDATE' ) );
- if ( $row === false ) {
- // Missing
- $db->commit();
-
- return null;
- }
- $db->delete( 'objectcache', array( 'keyname' => $key ), __METHOD__ );
- if ( $this->isExpired( $row->exptime ) ) {
- // Expired, do not reinsert
- $db->commit();
-
- return null;
- }
-
- $oldValue = intval( $this->unserialize( $db->decodeBlob( $row->value ) ) );
- $newValue = $oldValue + $step;
- $db->insert( 'objectcache',
- array(
- 'keyname' => $key,
- 'value' => $db->encodeBlob( $this->serialize( $newValue ) ),
- 'exptime' => $row->exptime
- ), __METHOD__, 'IGNORE' );
-
- if ( $db->affectedRows() == 0 ) {
- // Race condition. See bug 28611
- $newValue = null;
- }
- $db->commit();
- } catch ( DBQueryError $e ) {
- $this->handleWriteError( $e );
-
- return null;
- }
-
- return $newValue;
- }
-
- public function keys() {
- $db = $this->getDB();
- $res = $db->select( 'objectcache', array( 'keyname' ), false, __METHOD__ );
- $result = array();
-
- foreach ( $res as $row ) {
- $result[] = $row->keyname;
- }
-
- return $result;
- }
-
- protected function isExpired( $exptime ) {
- return $exptime != $this->getMaxDateTime() && wfTimestamp( TS_UNIX, $exptime ) < time();
- }
-
- protected function getMaxDateTime() {
- if ( time() > 0x7fffffff ) {
- return $this->getDB()->timestamp( 1 << 62 );
- } else {
- return $this->getDB()->timestamp( 0x7fffffff );
- }
- }
-
- protected function garbageCollect() {
- /* Ignore 99% of requests */
- if ( !mt_rand( 0, 100 ) ) {
- $now = time();
- /* Avoid repeating the delete within a few seconds */
- if ( $now > ( $this->lastExpireAll + 1 ) ) {
- $this->lastExpireAll = $now;
- $this->expireAll();
- }
- }
- }
-
- public function expireAll() {
- $db = $this->getDB();
- $now = $db->timestamp();
-
- try {
- $db->begin();
- $db->delete( 'objectcache', array( 'exptime < ' . $db->addQuotes( $now ) ), __METHOD__ );
- $db->commit();
- } catch ( DBQueryError $e ) {
- $this->handleWriteError( $e );
- }
- }
-
- public function deleteAll() {
- $db = $this->getDB();
-
- try {
- $db->begin();
- $db->delete( 'objectcache', '*', __METHOD__ );
- $db->commit();
- } catch ( DBQueryError $e ) {
- $this->handleWriteError( $e );
- }
- }
-
- /**
- * Serialize an object and, if possible, compress the representation.
- * On typical message and page data, this can provide a 3X decrease
- * in storage requirements.
- *
- * @param $data mixed
- * @return string
- */
- protected function serialize( &$data ) {
- $serial = serialize( $data );
-
- if ( function_exists( 'gzdeflate' ) ) {
- return gzdeflate( $serial );
- } else {
- return $serial;
- }
- }
-
- /**
- * Unserialize and, if necessary, decompress an object.
- * @param $serial string
- * @return mixed
- */
- protected function unserialize( $serial ) {
- if ( function_exists( 'gzinflate' ) ) {
- $decomp = @gzinflate( $serial );
-
- if ( false !== $decomp ) {
- $serial = $decomp;
- }
- }
-
- $ret = unserialize( $serial );
-
- return $ret;
- }
-
- /**
- * Handle a DBQueryError which occurred during a write operation.
- * Ignore errors which are due to a read-only database, rethrow others.
- */
- protected function handleWriteError( $exception ) {
- $db = $this->getDB();
-
- if ( !$db->wasReadOnlyError() ) {
- throw $exception;
- }
-
- try {
- $db->rollback();
- } catch ( DBQueryError $e ) {
- }
-
- wfDebug( __METHOD__ . ": ignoring query error\n" );
- $db->ignoreErrors( false );
- }
-}
-
-/**
- * Backwards compatibility alias
- */
-class MediaWikiBagOStuff extends SqlBagOStuff { }
-
-/**
- * This is a wrapper for APC's shared memory functions
- *
- * @ingroup Cache
- */
-class APCBagOStuff extends BagOStuff {
- public function get( $key ) {
- $val = apc_fetch( $key );
-
- if ( is_string( $val ) ) {
- $val = unserialize( $val );
- }
-
- return $val;
- }
-
- public function set( $key, $value, $exptime = 0 ) {
- apc_store( $key, serialize( $value ), $exptime );
-
- return true;
- }
-
- public function delete( $key, $time = 0 ) {
- apc_delete( $key );
-
- return true;
- }
-
- public function keys() {
- $info = apc_cache_info( 'user' );
- $list = $info['cache_list'];
- $keys = array();
-
- foreach ( $list as $entry ) {
- $keys[] = $entry['info'];
- }
-
- return $keys;
- }
-}
-
-/**
- * This is a wrapper for eAccelerator's shared memory functions.
- *
- * This is basically identical to the deceased Turck MMCache version,
- * mostly because eAccelerator is based on Turck MMCache.
- *
- * @ingroup Cache
- */
-class eAccelBagOStuff extends BagOStuff {
- public function get( $key ) {
- $val = eaccelerator_get( $key );
-
- if ( is_string( $val ) ) {
- $val = unserialize( $val );
- }
-
- return $val;
- }
-
- public function set( $key, $value, $exptime = 0 ) {
- eaccelerator_put( $key, serialize( $value ), $exptime );
-
- return true;
- }
-
- public function delete( $key, $time = 0 ) {
- eaccelerator_rm( $key );
-
- return true;
- }
-
- public function lock( $key, $waitTimeout = 0 ) {
- eaccelerator_lock( $key );
-
- return true;
- }
-
- public function unlock( $key ) {
- eaccelerator_unlock( $key );
-
- return true;
- }
-}
-
-/**
- * Wrapper for XCache object caching functions; identical interface
- * to the APC wrapper
- *
- * @ingroup Cache
- */
-class XCacheBagOStuff extends BagOStuff {
- /**
- * Get a value from the XCache object cache
- *
- * @param $key String: cache key
- * @return mixed
- */
- public function get( $key ) {
- $val = xcache_get( $key );
-
- if ( is_string( $val ) ) {
- $val = unserialize( $val );
- }
-
- return $val;
- }
-
- /**
- * Store a value in the XCache object cache
- *
- * @param $key String: cache key
- * @param $value Mixed: object to store
- * @param $expire Int: expiration time
- * @return bool
- */
- public function set( $key, $value, $expire = 0 ) {
- xcache_set( $key, serialize( $value ), $expire );
-
- return true;
- }
-
- /**
- * Remove a value from the XCache object cache
- *
- * @param $key String: cache key
- * @param $time Int: not used in this implementation
- * @return bool
- */
- public function delete( $key, $time = 0 ) {
- xcache_unset( $key );
-
- return true;
- }
-}
-
-/**
- * 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.
- *
- * @ingroup Cache
- */
-class DBABagOStuff extends BagOStuff {
- var $mHandler, $mFile, $mReader, $mWriter, $mDisabled;
-
- public function __construct( $dir = false ) {
- global $wgDBAhandler;
-
- if ( $dir === false ) {
- global $wgTmpDirectory;
- $dir = $wgTmpDirectory;
- }
-
- $this->mFile = "$dir/mw-cache-" . wfWikiID();
- $this->mFile .= '.db';
- wfDebug( __CLASS__ . ": using cache file {$this->mFile}\n" );
- $this->mHandler = $wgDBAhandler;
- }
-
- /**
- * Encode value and expiry for storage
- */
- function encode( $value, $expiry ) {
- # Convert to absolute time
- $expiry = $this->convertExpiry( $expiry );
-
- return sprintf( '%010u', intval( $expiry ) ) . ' ' . serialize( $value );
- }
-
- /**
- * @return list containing value first and expiry second
- */
- function decode( $blob ) {
- if ( !is_string( $blob ) ) {
- return array( null, 0 );
- } else {
- return array(
- unserialize( substr( $blob, 11 ) ),
- intval( substr( $blob, 0, 10 ) )
- );
- }
- }
-
- 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;
- }
-
- function getWriter() {
- $handle = dba_open( $this->mFile, 'cl', $this->mHandler );
-
- if ( !$handle ) {
- wfDebug( "Unable to open DBA cache file {$this->mFile}\n" );
- }
-
- return $handle;
- }
-
- function get( $key ) {
- wfProfileIn( __METHOD__ );
- wfDebug( __METHOD__ . "($key)\n" );
-
- $handle = $this->getReader();
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return null;
- }
-
- $val = dba_fetch( $key, $handle );
- list( $val, $expiry ) = $this->decode( $val );
-
- # Must close ASAP because locks are held
- dba_close( $handle );
-
- if ( !is_null( $val ) && $expiry && $expiry < time() ) {
- # Key is expired, delete it
- $handle = $this->getWriter();
- dba_delete( $key, $handle );
- dba_close( $handle );
- wfDebug( __METHOD__ . ": $key expired\n" );
- $val = null;
- }
-
- wfProfileOut( __METHOD__ );
- return $val;
- }
-
- 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;
- }
-
- function delete( $key, $time = 0 ) {
- wfProfileIn( __METHOD__ );
- wfDebug( __METHOD__ . "($key)\n" );
-
- $handle = $this->getWriter();
- if ( !$handle ) {
- wfProfileOut( __METHOD__ );
- return false;
- }
-
- $ret = dba_delete( $key, $handle );
- dba_close( $handle );
-
- wfProfileOut( __METHOD__ );
- return $ret;
- }
-
- 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( $value, $expiry ) = $this->decode( dba_fetch( $key, $handle ) );
-
- if ( $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;
- }
-
- function keys() {
- $reader = $this->getReader();
- $k1 = dba_firstkey( $reader );
-
- if ( !$k1 ) {
- return array();
- }
-
- $result[] = $k1;
-
- while ( $key = dba_nextkey( $reader ) ) {
- $result[] = $key;
- }
-
- return $result;
- }
-}
-
-/**
- * Wrapper for WinCache object caching functions; identical interface
- * to the APC wrapper
- *
- * @ingroup Cache
- */
-class WinCacheBagOStuff extends BagOStuff {
-
- /**
- * Get a value from the WinCache object cache
- *
- * @param $key String: cache key
- * @return mixed
- */
- public function get( $key ) {
- $val = wincache_ucache_get( $key );
-
- if ( is_string( $val ) ) {
- $val = unserialize( $val );
- }
-
- return $val;
- }
-
- /**
- * Store a value in the WinCache object cache
- *
- * @param $key String: cache key
- * @param $value Mixed: object to store
- * @param $expire Int: expiration time
- * @return bool
- */
- public function set( $key, $value, $expire = 0 ) {
- wincache_ucache_set( $key, serialize( $value ), $expire );
-
- return true;
- }
-
- /**
- * Remove a value from the WinCache object cache
- *
- * @param $key String: cache key
- * @param $time Int: not used in this implementation
- * @return bool
- */
- public function delete( $key, $time = 0 ) {
- wincache_ucache_delete( $key );
-
- return true;
- }
-
- public function keys() {
- $info = wincache_ucache_info();
- $list = $info['ucache_entries'];
- $keys = array();
-
- foreach ( $list as $entry ) {
- $keys[] = $entry['key_name'];
- }
-
- return $keys;
- }
-}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff