gzip compression gets enabled especially if you have disabled it in php.ini

[kajtzu@…]

Found in index.php:109:

if (function_exists('ob_gzhandler') && !ini_get('zlib.output_compression'))

ob_start('ob_gzhandler');

else

ob_start();

Translated it means that if the function exists (php was compiled with zlib) and zlib.output_compression is _OFF_ (see ​http://fi.php.net/ini_get for ini_get() return value semantics) we continue with gzip compression.

See ​http://support.microsoft.com/kb/321722 if you are interested in why this is bad; to summarize the resulting mess is that users on shared workstations (reception, etc.) start seeing each others emails as long as the UID is the same between inboxes.

Patch follows.

Also bug #1484221 is related to this, there is another way user messages can get cached.

[kajtzu@…]

don't compress unless zlib.output_compression is true, affects index.php

[seansan]

You know what? I have encountered this problem of seeing other peoples mails but never really was able to reproduce. Wonder if this was the problem.

[seansan]

This error occurs in beta2 (and also SVN) - altered version and added to milestone RC1

[seansan]

When fixing also see issue #1484221 (regarding reading other peoples e-mails)

[estadtherr]

The patch attempts to enable ob_gzhandler when zlib.compression is already enabled. Only one of those compression methods can be active at one time (I'm not sure which one wins when both are enabled). See ​ob_gzhandler page on php.net. The original intent of the logic was presumably to use ob_gzhandler iff zlib.compression was turned off, which makes sense. If it's just a bug with IE 5.x, maybe this should be a dontfix.

[thomasb]

Patch applied to Trunk ([ff52bee1]).
Let's try it this way.

[kaouete]

Hi,

I guess this is because of this patch that i get this warning with roundcube :
Warning: ob_start() [ref.outcontrol]: output handler 'ob_gzhandler' conflicts with 'zlib output compression' in /usr/share/roundcube/index.php on line 107

I just don't understand, one day (#1471069) someone says that zlib.output_compression should not be enabled with ob_gzhandler, someone says it too here, and just after the patch is applied to trunk, and now I get this warning on my debian that enable zlib.output_compression by default (I think, maybe I enabled it myself ... :)

Shouldn't it be reversed ? Or is there some explanation or this ?

[toots]

Note:  You cannot use both ob_gzhandler() and zlib.output_compression. 
Also note that using  zlib.output_compression is preferred over ob_gzhandler().

Seems to me that this note from php.net is clear enough to revert this patch...

[till]

I am reverting this.

According to the note on php.net this is obvious.