Zend_File_Transfer_Adapter_Abstract::_isPathWriteable() doesn't work in concurrent sessions

[dmitry-lomakin]

As the method operates on a temporary file with constant filename the check randomly fails if being executed in concurrent sessions due to race conditions. To fix that either a unique filename should be used in each check or the temporary file should be locked so concurrent sessions would be unable to remove it.

[froschdesign]

@instalic
Can you provide an unit test for the problem?

[dmitry-lomakin]

@froschdesign I'm afraid I'm not able to provide such unit test as the problem only occurs randomly when concurrent sessions are taking place. I can create a test which could provide like 50-70% probability of the problem occurrence but I don't think it's possible to create a unit test which would give 100% guarantee without actual code modification (of Zend_File_Transfer_Adapter_Abstract::_isPathWriteable()). Sorry.