Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:29383
Return-Path: <phpinternals@thunder-2000.com>
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Delivered-To: mailing list internals@lists.php.net
Received: (qmail 87817 invoked by uid 1010); 9 May 2007 17:47:23 -0000
Delivered-To: ezmlm-scan-internals@lists.php.net
Delivered-To: ezmlm-internals@lists.php.net
Received: (qmail 87802 invoked from network); 9 May 2007 17:47:23 -0000
Received: from unknown (HELO lists.php.net) (127.0.0.1)
  by localhost with SMTP; 9 May 2007 17:47:23 -0000
X-Host-Fingerprint: 88.67.25.66 dslb-088-067-025-066.pools.arcor-ip.net  
Received: from [88.67.25.66] ([88.67.25.66:6128] helo=localhost.localdomain)
	by pb1.pair.com (ecelerity 2.1.1.9-wez r(12769M)) with ESMTP
	id 4C/91-60325-92902464 for <internals@lists.php.net>; Wed, 09 May 2007 13:47:23 -0400
Message-ID: <4C.91.60325.92902464@pb1.pair.com>
To: internals@lists.php.net
Date: Wed, 09 May 2007 19:47:20 +0200
User-Agent: Thunderbird 2.0.0.0 (Windows/20070326)
MIME-Version: 1.0
References: <0E.B4.18102.F9DB9264@pb1.pair.com> <463F9FD0.3030009@zend.com> <463FA701.5030707@pooteeweet.org> <alpine.DEB.0.98.0705080816280.27587@kossu.ez.no> <46406F89.7030000@zend.com> <alpine.DEB.0.98.0705081448020.27587@kossu.ez.no> <4640749E.20005@zend.com> <alpine.DEB.0.98.0705081508190.27587@kossu.ez.no> <46407819.40808@zend.com> <46407B27.1010705@pooteeweet.org> <46409661.4000106@zend.com>
In-Reply-To: <46409661.4000106@zend.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
X-Posted-By: 88.67.25.66
Subject: Re: [PHP-DEV] serialize and cache handling
From: phpinternals@thunder-2000.com (Mathias Bank)

> If his cache had no locking before, what changed?

Well, I have been using several cache classes. A good cache class is the
pear cache light.

This cache is serializing your data and write this data to a file - of
course with file locking.

I could imagine, that a improved serialize-function could work like this:

$fp = @fopen($filename, "wb");
if ($fp) {
  @flock($fp, LOCK_EX);
  serialize($data,$fp);
  @flock($fp, LOCK_UN);
  @fclose($fp);
}


This method makes it possible to decide, if you want to use a locking
function or not.

The same technique could be applied to imagepng (and others):
instead of writing

  imagepng($img,"/path/to/file");

it would be better to write

$fp = @fopen($filename, "wb");
if ($fp) {
  @flock($fp, LOCK_EX);
  imagepng($img,$fp);
  @flock($fp, LOCK_UN);
  @fclose($fp);
}

This way, you can decide, if you want to use locking functions or not. I
think, this could be a big improvement (until now you have to use
imagepng in combination with ob_start / ob_get_contents / ob_end_clean
to cache images in a secure way).

Mathias