Your IP : 172.69.214.232
<?php
/**
* 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 = 4;
/* private */ var $mGoodLinks, $mBadLinks;
/* private */ var $mForUpdate;
/**
* Get an instance of this class
*/
static function &singleton() {
static $instance;
if ( !isset( $instance ) ) {
$instance = new LinkCache;
}
return $instance;
}
function __construct() {
$this->mForUpdate = false;
$this->mGoodLinks = array();
$this->mGoodLinkFields = array();
$this->mBadLinks = array();
}
/**
* 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 {
return 0;
}
}
/**
* Get a field of a title object from cache.
* If this link is not good, it will return NULL.
* @param Title $title
* @param string $field ('length','redirect')
* @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;
}
}
public function isBadLink( $title ) {
return array_key_exists( $title, $this->mBadLinks );
}
/**
* Add a link for the title to the link cache
* @param int $id
* @param Title $title
* @param int $len
* @param int $redir
*/
public function addGoodLinkObj( $id, $title, $len = -1, $redir = null ) {
$dbkey = $title->getPrefixedDbKey();
$this->mGoodLinks[$dbkey] = intval( $id );
$this->mGoodLinkFields[$dbkey] = array(
'length' => intval( $len ),
'redirect' => intval( $redir ) );
}
public function addBadLinkObj( $title ) {
$dbkey = $title->getPrefixedDbKey();
if ( !$this->isBadLink( $dbkey ) ) {
$this->mBadLinks[$dbkey] = 1;
}
}
public function clearBadLink( $title ) {
unset( $this->mBadLinks[$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]);
}
}
public function getGoodLinks() { return $this->mGoodLinks; }
public function getBadLinks() { return array_keys( $this->mBadLinks ); }
/**
* Add a title to the link cache, return the page_id or zero if non-existent
* @param $title String: title to add
* @param $len int, page size
* @param $redir bool, is redirect?
* @return integer
*/
public function addLink( $title, $len = -1, $redir = null ) {
$nt = Title::newFromDBkey( $title );
if( $nt ) {
return $this->addLinkObj( $nt, $len, $redir );
} else {
return 0;
}
}
/**
* Add a title to the link cache, return the page_id or zero if non-existent
* @param $nt Title to add.
* @param $len int, page size
* @param $redir bool, is redirect?
* @return integer
*/
public function addLinkObj( &$nt, $len = -1, $redirect = null ) {
global $wgAntiLockFlags, $wgProfiler;
wfProfileIn( __METHOD__ );
$key = $nt->getPrefixedDBkey();
if ( $this->isBadLink( $key ) ) {
wfProfileOut( __METHOD__ );
return 0;
}
$id = $this->getGoodLinkID( $key );
if ( $id != 0 ) {
wfProfileOut( __METHOD__ );
return $id;
}
if ( $key === '' ) {
wfProfileOut( __METHOD__ );
return 0;
}
# Some fields heavily used for linking...
if ( $this->mForUpdate ) {
$db = wfGetDB( DB_MASTER );
if ( !( $wgAntiLockFlags & ALF_NO_LINK_LOCK ) ) {
$options = array( 'FOR UPDATE' );
} else {
$options = array();
}
} else {
$db = wfGetDB( DB_SLAVE );
$options = array();
}
$s = $db->selectRow( 'page',
array( 'page_id', 'page_len', 'page_is_redirect' ),
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 );
} else {
$len = -1;
$redirect = 0;
}
if ( $id == 0 ) {
$this->addBadLinkObj( $nt );
} else {
$this->addGoodLinkObj( $id, $nt, $len, $redirect );
}
wfProfileOut( __METHOD__ );
return $id;
}
/**
* Clears cache
*/
public function clear() {
$this->mGoodLinks = array();
$this->mGoodLinkFields = array();
$this->mBadLinks = array();
}
}