<?php
-# Cache for article titles (prefixed DB keys) and ids linked from one source
-
-# These are used in incrementalSetup()
-define ('LINKCACHE_GOOD', 0);
-define ('LINKCACHE_BAD', 1);
-define ('LINKCACHE_IMAGE', 2);
-
-class LinkCache {
+/**
+ * Cache for article titles (prefixed DB keys) and ids linked from one source
+ *
+ * @ingroup Cache
+ */
+class LinkCache {
// Increment $mClassVer whenever old serialized versions of this class
// becomes incompatible with the new version.
- /* private */ var $mClassVer = 2;
+ /* private */ var $mClassVer = 4;
+
+ /* private */ var $mGoodLinks, $mBadLinks;
+ /* private */ var $mForUpdate;
- /* private */ var $mGoodLinks, $mBadLinks, $mActive;
- /* private */ var $mImageLinks, $mCategoryLinks;
- /* private */ var $mPreFilled, $mOldGoodLinks, $mOldBadLinks;
-
- /* private */ function getKey( $title ) {
- global $wgDBname;
- return "$wgDBname:lc:title:$title";
+ /**
+ * Get an instance of this class
+ */
+ static function &singleton() {
+ static $instance;
+ if ( !isset( $instance ) ) {
+ $instance = new LinkCache;
+ }
+ return $instance;
}
-
- function LinkCache()
- {
- $this->mActive = true;
- $this->mPreFilled = false;
+
+ function __construct() {
+ $this->mForUpdate = false;
$this->mGoodLinks = array();
+ $this->mGoodLinkFields = array();
$this->mBadLinks = array();
- $this->mImageLinks = array();
- $this->mCategoryLinks = array();
- $this->mOldGoodLinks = array();
- $this->mOldBadLinks = array();
}
- function getGoodLinkID( $title )
- {
+ /**
+ * General accessor to get/set whether SELECT FOR UPDATE should be used
+ */
+ public function forUpdate( $update = null ) {
+ return wfSetVar( $this->mForUpdate, $update );
+ }
+
+ public function getGoodLinkID( $title ) {
if ( array_key_exists( $title, $this->mGoodLinks ) ) {
return $this->mGoodLinks[$title];
} else {
}
}
- function isBadLink( $title )
- {
- return array_key_exists( $title, $this->mBadLinks );
- }
-
- function addGoodLink( $id, $title )
- {
- if ( $this->mActive ) {
- $this->mGoodLinks[$title] = $id;
+ /**
+ * Get a field of a title object from cache.
+ * If this link is not good, it will return NULL.
+ * @param $title Title
+ * @param $field String: ('length','redirect','revision')
+ * @return mixed
+ */
+ public function getGoodLinkFieldObj( $title, $field ) {
+ $dbkey = $title->getPrefixedDbKey();
+ if ( array_key_exists( $dbkey, $this->mGoodLinkFields ) ) {
+ return $this->mGoodLinkFields[$dbkey][$field];
+ } else {
+ return null;
}
}
- function addBadLink( $title )
- {
- if ( $this->mActive && ( ! $this->isBadLink( $title ) ) ) {
- $this->mBadLinks[$title] = 1;
- }
+ public function isBadLink( $title ) {
+ return array_key_exists( $title, $this->mBadLinks );
}
- function addImageLink( $title )
- {
- if ( $this->mActive ) { $this->mImageLinks[$title] = 1; }
+ /**
+ * Add a link for the title to the link cache
+ *
+ * @param $id Integer: page's ID
+ * @param $title Title object
+ * @param $len Integer: text's length
+ * @param $redir Integer: whether the page is a redirect
+ * @param $revision Integer: latest revision's ID
+ */
+ public function addGoodLinkObj( $id, $title, $len = -1, $redir = null, $revision = false ) {
+ $dbkey = $title->getPrefixedDbKey();
+ $this->mGoodLinks[$dbkey] = intval( $id );
+ $this->mGoodLinkFields[$dbkey] = array(
+ 'length' => intval( $len ),
+ 'redirect' => intval( $redir ),
+ 'revision' => intval( $revision ) );
}
- function addImageLinkObj( $nt )
- {
- if ( $this->mActive ) { $this->mImageLinks[$nt->getDBkey()] = 1; }
- }
-
- function addCategoryLink( $title, $sortkey ) {
- if ( $this->mActive ) { $this->mCategoryLinks[$title] = $sortkey; }
- }
-
- function addCategoryLinkObj( &$nt, $sortkey ) {
- $this->addCategoryLink( $nt->getDBkey(), $sortkey );
+ public function addBadLinkObj( $title ) {
+ $dbkey = $title->getPrefixedDbKey();
+ if ( !$this->isBadLink( $dbkey ) ) {
+ $this->mBadLinks[$dbkey] = 1;
+ }
}
- function clearBadLink( $title )
- {
+ public function clearBadLink( $title ) {
unset( $this->mBadLinks[$title] );
- $this->clearLink( $title );
}
-
- function clearLink( $title )
- {
- global $wgMemc, $wgLinkCacheMemcached;
- if( $wgLinkCacheMemcached )
- $wgMemc->delete( $this->getKey( $title ) );
+
+ public function clearLink( $title ) {
+ $dbkey = $title->getPrefixedDbKey();
+ if( isset($this->mBadLinks[$dbkey]) ) {
+ unset($this->mBadLinks[$dbkey]);
+ }
+ if( isset($this->mGoodLinks[$dbkey]) ) {
+ unset($this->mGoodLinks[$dbkey]);
+ }
+ if( isset($this->mGoodLinkFields[$dbkey]) ) {
+ unset($this->mGoodLinkFields[$dbkey]);
+ }
}
- function suspend() { $this->mActive = false; }
- function resume() { $this->mActive = true; }
- function getGoodLinks() { return $this->mGoodLinks; }
- function getBadLinks() { return array_keys( $this->mBadLinks ); }
- function getImageLinks() { return $this->mImageLinks; }
- function getCategoryLinks() { return $this->mCategoryLinks; }
+ public function getGoodLinks() { return $this->mGoodLinks; }
+ public function getBadLinks() { return array_keys( $this->mBadLinks ); }
- function addLink( $title )
- {
+ /**
+ * Add a title to the link cache, return the page_id or zero if non-existent
+ *
+ * @param $title String: title to add
+ * @return Integer
+ */
+ public function addLink( $title ) {
$nt = Title::newFromDBkey( $title );
if( $nt ) {
return $this->addLinkObj( $nt );
return 0;
}
}
-
- function addLinkObj( &$nt )
- {
- global $wgMemc, $wgLinkCacheMemcached;
- $title = $nt->getPrefixedDBkey();
- if ( $this->isBadLink( $title ) ) { return 0; }
- $id = $this->getGoodLinkID( $title );
- if ( 0 != $id ) { return $id; }
-
- $fname = "LinkCache::addLinkObj";
- wfProfileIn( $fname );
- $ns = $nt->getNamespace();
- $t = $nt->getDBkey();
-
- if ( "" == $title ) {
- wfProfileOut( $fname );
- return 0;
- }
-
- $id = NULL;
- if( $wgLinkCacheMemcached )
- $id = $wgMemc->get( $key = $this->getKey( $title ) );
- if( ! is_integer( $id ) ) {
- $sql = "SELECT cur_id FROM cur WHERE cur_namespace=" .
- "{$ns} AND cur_title='" . wfStrencode( $t ) . "'";
- $res = wfQuery( $sql, DB_READ, "LinkCache::addLink" );
-
- if ( 0 == wfNumRows( $res ) ) {
- $id = 0;
- } else {
- $s = wfFetchObject( $res );
- $id = $s->cur_id;
- }
- if( $wgLinkCacheMemcached )
- $wgMemc->add( $key, $id, 3600*24 );
- }
-
- if ( 0 == $id ) { $this->addBadLink( $title ); }
- else { $this->addGoodLink( $id, $title ); }
- wfProfileOut( $fname );
- return $id;
- }
-
- function preFill( &$fromtitle )
- {
- global $wgEnablePersistentLC;
-
- $fname = "LinkCache::preFill";
- wfProfileIn( $fname );
- # Note -- $fromtitle is a Title *object*
-
- $this->suspend();
- $id = $fromtitle->getArticleID();
- $this->resume();
-
- if( $id == 0 ) {
- wfDebug( "$fname - got id 0 for title '" . $fromtitle->getPrefixedDBkey() . "'\n" );
- wfProfileOut( $fname );
- return;
- }
-
- if ( $wgEnablePersistentLC ) {
- if( $this->fillFromLinkscc( $id ) ){
- wfProfileOut( $fname );
- return;
- }
- }
-
- $sql = "SELECT cur_id,cur_namespace,cur_title
- FROM cur,links
- WHERE cur_id=l_to AND l_from=$id";
- $res = wfQuery( $sql, DB_READ, $fname );
- while( $s = wfFetchObject( $res ) ) {
- $this->addGoodLink( $s->cur_id,
- Title::makeName( $s->cur_namespace, $s->cur_title )
- );
- }
-
- $sql = "SELECT bl_to
- FROM brokenlinks
- WHERE bl_from='{$id}'";
- $res = wfQuery( $sql, DB_READ, "LinkCache::preFill" );
- while( $s = wfFetchObject( $res ) ) {
- $this->addBadLink( $s->bl_to );
- }
-
- $this->mOldBadLinks = $this->mBadLinks;
- $this->mOldGoodLinks = $this->mGoodLinks;
- $this->mPreFilled = true;
-
- if ( $wgEnablePersistentLC ) {
- $this->saveToLinkscc( $id );
- }
- wfProfileOut( $fname );
- }
-
- function getGoodAdditions()
- {
- return array_diff( $this->mGoodLinks, $this->mOldGoodLinks );
- }
+ /**
+ * Add a title to the link cache, return the page_id or zero if non-existent
+ *
+ * @param $nt Title object to add
+ * @return Integer
+ */
+ public function addLinkObj( $nt ) {
+ global $wgAntiLockFlags;
+ wfProfileIn( __METHOD__ );
- function getBadAdditions()
- {
- #wfDebug( "mOldBadLinks: " . implode( ', ', array_keys( $this->mOldBadLinks ) ) . "\n" );
- #wfDebug( "mBadLinks: " . implode( ', ', array_keys( $this->mBadLinks ) ) . "\n" );
- return array_values( array_diff( array_keys( $this->mBadLinks ), array_keys( $this->mOldBadLinks ) ) );
- }
-
- function getImageAdditions()
- {
- return array_diff_assoc( $this->mImageLinks, $this->mOldImageLinks );
- }
-
- function getGoodDeletions()
- {
- return array_diff( $this->mOldGoodLinks, $this->mGoodLinks );
- }
-
- function getBadDeletions()
- {
- return array_values( array_diff( array_keys( $this->mOldBadLinks ), array_keys( $this->mBadLinks ) ));
- }
-
- function getImageDeletions()
- {
- return array_diff_assoc( $this->mOldImageLinks, $this->mImageLinks );
- }
-
- # Parameters: $which is one of the LINKCACHE_xxx constants, $del and $add are
- # the incremental update arrays which will be filled. Returns whether or not it's
- # worth doing the incremental version. For example, if [[List of mathematical topics]]
- # was blanked, it would take a long, long time to do incrementally.
- function incrementalSetup( $which, &$del, &$add )
- {
- if ( ! $this->mPreFilled ) {
- return false;
- }
-
- switch ( $which ) {
- case LINKCACHE_GOOD:
- $old =& $this->mOldGoodLinks;
- $cur =& $this->mGoodLinks;
- $del = $this->getGoodDeletions();
- $add = $this->getGoodAdditions();
- break;
- case LINKCACHE_BAD:
- $old =& $this->mOldBadLinks;
- $cur =& $this->mBadLinks;
- $del = $this->getBadDeletions();
- $add = $this->getBadAdditions();
- break;
- default: # LINKCACHE_IMAGE
- return false;
- }
-
- return true;
- }
-
- # Clears cache but leaves old preFill copies alone
- function clear()
- {
- $this->mGoodLinks = array();
- $this->mBadLinks = array();
- $this->mImageLinks = array();
- }
-
- /* private */ function fillFromLinkscc( $id ){
- $id = IntVal( $id );
- $res = wfQuery("SELECT lcc_cacheobj FROM linkscc WHERE lcc_pageid = $id",
- DB_READ);
- $row = wfFetchObject( $res );
- if( $row == FALSE)
- return false;
-
- $cacheobj = false;
- if( function_exists( "gzuncompress" ) )
- $cacheobj = @gzuncompress( $row->lcc_cacheobj );
-
- if($cacheobj == FALSE){
- $cacheobj = $row->lcc_cacheobj;
+ $key = $nt->getPrefixedDBkey();
+ if ( $this->isBadLink( $key ) || $nt->isExternal() ) {
+ wfProfileOut( __METHOD__ );
+ return 0;
}
- $cc = @unserialize( $cacheobj );
- if( isset( $cc->mClassVer ) and ($cc->mClassVer == $this->mClassVer ) ){
- $this->mOldGoodLinks = $this->mGoodLinks = $cc->mGoodLinks;
- $this->mOldBadLinks = $this->mBadLinks = $cc->mBadLinks;
- $this->mPreFilled = true;
- return TRUE;
- } else {
- return FALSE;
+ $id = $this->getGoodLinkID( $key );
+ if ( $id != 0 ) {
+ wfProfileOut( __METHOD__ );
+ return $id;
}
- }
-
- /* private */ function saveToLinkscc( $pid ){
- global $wgCompressedPersistentLC, $wgIsMySQL;
- if( $wgCompressedPersistentLC and function_exists( "gzcompress" ) ) {
- $ser = wfStrencode( gzcompress( serialize( $this ), 3 ));
- } else {
- $ser = wfStrencode( serialize( $this ) );
- }
- if ($isMySQL) {
- wfQuery("REPLACE INTO linkscc(lcc_pageid,lcc_cacheobj) " .
- "VALUES({$pid}, '{$ser}')", DB_WRITE);
- } else {
- wfQuery("DELETE FROM linkscc WHERE lcc_pageid={$pid}",DB_WRITE);
- wfQuery("INSERT INTO linkscc(lcc_pageid,lcc_cacheobj) " .
- "VALUES({$pid}, '{$ser}')", DB_WRITE);
+ if ( $key === '' ) {
+ wfProfileOut( __METHOD__ );
+ return 0;
}
- }
- # $pid is a page id
- /* static */ function linksccClearLinksTo( $pid ){
- global $wgEnablePersistentLC, $wgIsMySQL;
- if ( $wgEnablePersistentLC ) {
- $pid = intval( $pid );
- if ($wgIsMySQL) {
- wfQuery("DELETE linkscc FROM linkscc,links ".
- "WHERE lcc_pageid=links.l_from AND l_to={$pid}", DB_WRITE);
+ # Some fields heavily used for linking...
+ if ( $this->mForUpdate ) {
+ $db = wfGetDB( DB_MASTER );
+ if ( !( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) ) {
+ $options = array( 'FOR UPDATE' );
} else {
- wfQuery("DELETE FROM linkscc WHERE lcc_pageid IN ".
- "(SELECT l_from FROM links WHERE l_to={$pid}", DB_WRITE);
+ $options = array();
}
- wfQuery("DELETE FROM linkscc WHERE lcc_pageid='{$pid}')", DB_WRITE);
+ } else {
+ $db = wfGetDB( DB_SLAVE );
+ $options = array();
+ }
+
+ $s = $db->selectRow( 'page',
+ array( 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
+ array( 'page_namespace' => $nt->getNamespace(), 'page_title' => $nt->getDBkey() ),
+ __METHOD__, $options );
+ # Set fields...
+ if ( $s !== false ) {
+ $id = intval( $s->page_id );
+ $len = intval( $s->page_len );
+ $redirect = intval( $s->page_is_redirect );
+ $revision = intval( $s->page_latest );
+ } else {
+ $id = 0;
+ $len = -1;
+ $redirect = 0;
+ $revision = 0;
}
- }
- # $title is a prefixed db title, for example like Title->getPrefixedDBkey() returns.
- /* static */ function linksccClearBrokenLinksTo( $title ){
- global $wgEnablePersistentLC,$wgIsMySQL;
- if ( $wgEnablePersistentLC ) {
- $title = wfStrencode( $title );
- if ($wgIsMySQL) {
- wfQuery("DELETE linkscc FROM linkscc,brokenlinks ".
- "WHERE lcc_pageid=bl_from AND bl_to='{$title}'", DB_WRITE);
- } else {
- wfQuery("DELETE FROM linkscc WHERE lcc_pageid IN ".
- "(SELECT bl_from FROM brokenlinks ".
- "WHERE bl_to='{$title}')",DB_WRITE);
- }
+ if ( $id == 0 ) {
+ $this->addBadLinkObj( $nt );
+ } else {
+ $this->addGoodLinkObj( $id, $nt, $len, $redirect, $revision );
}
+ wfProfileOut( __METHOD__ );
+ return $id;
}
- # $pid is a page id
- /* static */ function linksccClearPage( $pid ){
- global $wgEnablePersistentLC;
- if ( $wgEnablePersistentLC ) {
- $pid = intval( $pid );
- wfQuery("DELETE FROM linkscc WHERE lcc_pageid='{$pid}'", DB_WRITE);
- }
+ /**
+ * Clears cache
+ */
+ public function clear() {
+ $this->mGoodLinks = array();
+ $this->mGoodLinkFields = array();
+ $this->mBadLinks = array();
}
}
-?>