Implementation of Zend_Cache_Backend_TwoLevels::_getFastLifetime is incorrect.

[ragnese]

Link:

zf1-future/library/Zend/Cache/Backend/TwoLevels.php

Line 520 in b87c150

private function _getFastLifetime($lifetime, $priority, $maxLifetime = null)

I discovered this issue in a project of ours that is using an ancient version of the original Zend_* stuff (before zf1-future existed), and it looks like it carried all the way over to today without being caught/fixed.

The problem is with how this method is called in the save method:

zf1-future/library/Zend/Cache/Backend/TwoLevels.php

Line 206 in b87c150

$fastLifetime = $this->_getFastLifetime($lifetime, $priority);

.

It's called with the default argument for $maxLifetime, which is null. The problem is that _getFastLifetime will always return null when $maxLifetime is null. This is because, if ($maxLifetime >= 0 && $fastLifetime > $maxLifetime) will always evaluate to true when $maxLifetime is null, and will therefore return $maxLifetime (null).

So the fast cache values are always being inserted with no lifetime/TTL and will never expire.