Re: PHP 4.0 Bug #7646 Updated: Objects inside session variables get lost

Why was this closed? No comment? --Jani On 16 Nov 2000 onn@php.net wrote: >ID: 7646 >Updated by: onn >Reported By: martijnklingens@netscape.net >Status: Closed >Bug Type: Scripting Engine problem >Assigned To: >Comments: > > > >Previous Comments: >--------------------------------------------------------------------------- > >[2000-11-05 07:45:14] martijnklingens@netscape.net >Hi, > >I encountered a strange bug in PHP when a session variable (an object in my case) holds >instances of other classes. As soon as I call a method on such an embedded instance, the instance is >lost the next time a page is loaded. > >I guess the garbage collector is a little bit too good and cleans up objects that are still in >use, but I'm not completely sure about that. > >_READING_ a variable (as opposed to calling methods) does not trigger the bug, so a workaround >is copying the object and calling the method on the copy, but I guess it should be fixed >nevertheless. > >Below is a script that reliably reproduces the bug on my system. It's rather large, but >with all the echo statements it should be immediately clear what it does. If you still have >questions about the script or about my configuration, feel free to drop me an email at >martijnklingens@netscape.net > >Thanks in advance for your help, > >Martijn Klingens > >Script Below ------> ><?PHP > >// Class A is the session var that holds instances of class B >class A >{ > var $Items = array (); > > function A () > { > $this->Items [] = new B ("B1"); > $this->Items [] = new B ("B2"); > } >} > >class B >{ > var $Value; > > function B ($Value) > { > $this->Value = $Value; > } > > function SomeFunction () > { > // Just do nothing, calling the method is enough to trigger the bug > } >} > >session_register ("MyA"); >session_register ("Count"); > >echo ("<html><body><pre>"); > >// Create A if it doesn't exist: >if (!isset ($MyA)) >{ > echo ("Creating session and instance of MyA...nn"); > $MyA = new A; > $Count = 1; // Current Step > echo ("Dump of MyA:n"); > print_r ($MyA); > echo ("n<a href=$PHP_SELF>Go to step 2</a>n"); >} >else >{ > // Session is registered already, call method on class B: > $Count++; > echo ("Session is already registeredn"); > echo ("You are now in step $Count. MyA holds:n"); > print_r ($MyA); > if ($Count == 2) // Step 2, i.e. trigger the bug? > { > echo ("nCalling method on MyA->Items [0].n"); > $MyA->Items [0]->SomeFunction (); > echo ("Done. MyA now still holds the same data:n"); > print_r ($MyA); > echo ("nIf you go to the next step, you'll notice that the Itemn"); > echo ("on which we just called our method got lost when the sessionn"); > echo ("variable was stored by PHP!n"); > echo ("<a href=$PHP_SELF>Go to the last step</a>"); > } > else > echo ("Notice that MyA->Items [0] no longer exists!"); >} > >echo ("</pre></body></html>"); >?> > > >--------------------------------------------------------------------------- > > >Full Bug description available at: http://bugs.php.net/?id=7646 > > >