#39254 [Opn]: Refcount error with static variables and object references

ID: 39254 User updated by: benoit dot heinrich at swisscom dot com Reported By: benoit dot heinrich at swisscom dot com Status: Open Bug Type: Class/Object related Operating System: Linux PHP Version: 4.4.4 New Comment: I tried to find a workaround, and when I tried to use the 'global' keyword instead of the 'static' then it gives exactly the same problem. I'm still searching for a workaround but for now I have nothing. Cheers, /Benoit Previous Comments: ------------------------------------------------------------------------ [2006-10-25 14:11:12] benoit dot heinrich at swisscom dot com I'm sorry but I'm using php 4.4 and I can't use PHP 5 for a lot of reasons. Do you have any fix for php 4.4 ? Cheers, /Benoit ------------------------------------------------------------------------ [2006-10-25 14:01:12] tony2001@php.net Please try using this CVS snapshot: http://snaps.php.net/php5.2-latest.tar.gz For Windows: http://snaps.php.net/win32/php5.2-win32-latest.zip ------------------------------------------------------------------------ [2006-10-25 13:54:06] benoit dot heinrich at swisscom dot com Description: ------------ Hello all, I've a script that keep an object into a cache to speed up performances. To access the cached instance, I'm using a static method of the class MyFactory::getInstance(); In that method I need to have a reference on the instance itself because the attached params also need to have a reference on their owner. Case 1 --------------------------------- If I do $instance =& new MyFactory(); in the getInstance() method then I have this: $a->code: 2 $a->params[toto]->parent->code: 2 $b->code: 1657232709 $b->params[toto]->parent->code: 1657232709 So the thing here is that the static keyword does not seems to keep a refcount on the instance when it's created the first time. So each time you call the getInstance() it creates a new instance instead of keeping the first created one. Case 2 --------------------------------- If I do $instance = new MyFactory(); in the getInstance() method then I have this: $a->code: 2 $a->params[toto]->parent->code: 576672258 $b->code: 2 $b->params[toto]->parent->code: 576672258 Here we have the result we can expect accordingly to the PHP4 documentation, but this not what I need. Please, can you investigate on that one ? Cheers, /Benoit Reproduce code: --------------- <?php error_reporting(E_ALL); /** * This is an example of a param implementation class. * The constructor always need a reference on its parent * (here it's not really needed, but in the real code it is) */ class toto { var $parent; function toto(&$parent) { $this->parent =& $parent; } } /** * This the factory class used to create instances of params. * The factory instance must be unique. */ class MyFactory { var $code; var $params = array(); function MyFactory() { $this->code = rand(); $this->initParam('toto'); } /** * Initialize a parameter */ function initParam($param) { $this->params[$param] =& new $param($this); } /** * Get the unique instance of the factory */ function & getInstance() { static $instance; // Due to the bug $instance is always null if (is_null($instance)) $instance =& new MyFactory(); return $instance; } } $a =& MyFactory::getInstance(); $a->code = 2; print '$a->code: ' . $a->code . "\n"; print '$a->params[toto]->parent->code: ' . $a->params['toto']->parent->code . "\n"; $b =& MyFactory::getInstance(); print '$b->code: ' . $b->code . "\n"; print '$b->params[toto]->parent->code: ' . $b->params['toto']->parent->code . "\n"; ?> Expected result: ---------------- $a->code: 2 $a->params[toto]->parent->code: 2 $b->code: 2 $b->params[toto]->parent->code: 2 Actual result: -------------- $a->code: 2 $a->params[toto]->parent->code: 2 $b->code: 1657232709 $b->params[toto]->parent->code: 1657232709 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=39254&edit=1