Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:29498
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain l-i-e.com from 67.139.134.202 cause and error)
Message-ID: <1574.208.54.67.44.1179427215.squirrel@www.l-i-e.com>
In-Reply-To: <38.B7.39652.C93F9464@pb1.pair.com>
References: <38.B7.39652.C93F9464@pb1.pair.com>
Date: Thu, 17 May 2007 13:40:15 -0500 (CDT)
To: "Emil Ivanov" <emil.vladev@gmail.com>
Cc: internals@lists.php.net
Reply-To: ceo@l-i-e.com
User-Agent: Hostbaby Webmail
MIME-Version: 1.0
Content-Type: text/plain;charset=iso-8859-1
Content-Transfer-Encoding: 8bit
Importance: Normal
Subject: Re: [PHP-DEV] register_session_gc_handler proposal
From: ceo@l-i-e.com ("Richard Lynch")

On Tue, May 15, 2007 12:53 pm, Emil Ivanov wrote:
> Sorry to bother you, as I know you are quite busy, but I have a
> problem and
> maybe a elegant solution does not exist right now.
>
> The case is simple:
> A user is allowed to upload files to the server, which are store in a
> temporary location and their filenames are stored in the session.

Store the filename somewhere else as well?

> The user leaves the site and the session gets destroyed, but the files
> remain untouched.
> If I can hook to the gc session function that will solve my case, but
> currently with session_set_save_handler I have to rewrite session
> handling,
> which I don't need...

You'd only need to override the session_destroy function, and, as I
recall, you can override just ONE of the functions somehow...  By
passing in NULL for the other args to session_set_save_handler maybe? 
Or maybe that was just a proposal of how to do that...

> So a simple hook will be very useful.

A simple HACK and probably a Bad Idea would be to cron a walk through
every session file and make an array of the files in user and then the
directory of files uploaded hanging around and array_difference the
two and nuke the unused files.

Just be SURE you always set the $_SESSION var and call
session_write_close *before* you move the file, or you'll end up with
a race condition where you end up nuking a file that hasn't had its
session data written to disk yet.

Document the hell out of this if you do it, or you'll end up
re-factoring and messing that race condition up, and you'll have an
intermittent bug that appears mostly under heavy load, probably.
[shudder]

> I know there are problems as how will I know which entry has been
> destroyed...

Overriding the session handler is not all that hard, really, and
probably the best available widely-understood idiom.

-- 
Some people have a "gift" link here.
Know what I want?
I want you to buy a CD from some indie artist.
http://cdbaby.com/browse/from/lynch
Yeah, I get a buck. So?