Change the way lifetime works in ext/libxml and ext/dom
Previously, a node could be freed even when holding a userland reference
to it. This resulted in exceptions when trying to access that node after
it has been implicitly or explicitly removed. After this patch, a node
will only be freed when the last userland reference disappears.
Fixes GH-9628.
Closes GH-11576.
When not providing a pad string, *and* not having other defaulted
arguments, the function would crash on a NULL pad zend_string*.
Despite testing with an empty pad string, the issue wasn't found because
when using named arguments the pad string *is* filled in.
The issue might be that due to slow instrumentation the process might end before
we get to add it to the processes list. If the SIGCHLD handler executes before
adding the process to the list it will never be removed again.
Previously, if an object had RC1 it would never be recorded in
php_serialize_data.ht because it was assumed that it could not be encountered
again. This assumption is incorrect though as the object itself may be saved
inside an array with RCn. This results in a new instance of the object, instead
of a second reference to the same object.
This is solved by tracking these objects in php_serialize_data.ht. To retain
performance, track if the current object resides in a potentially nested RCn
array. If not, and if the object is RC1 itself it may be omitted from
php_serialize_data.ht.
Additionally, we may treat the array root itself as RC1 because it may not
appear in the object graph again without recursion. Recursive arrays are still
somewhat broken even with this change, as the tracking of the array only happens
when the reference is encountered, thus resulting in a -> a' -> a' for a self
recursive array a -> a. Recursive arrays have limited support in serialize
anyway, so we ignore this case for now.
Co-authored-by: Dmitry Stogov <dmitry@zend.com>
Co-authored-by: Martin Hoch <martin@littlerobot.de>
Closes GH-11349
Closes GH-11305
For the past 20 years this threw a "not yet implemented" exception. But
the function was actually there (albeit not documented) and could be called...
Closes GH-11333.
* Remove obsolete workaround code
This code was for libxml2 <= 2.6.14. PHP requires at least libxml2
2.9.0.
* Use an inline check instead of calling into the library for an empty string check
When you construct a DOM tree containing subtrees which are constructed
top-down, this won't remove the redundant namespaces. That's because the
following conditions hold:
1) The namespace are reused from the doc->oldNs list.
2) Therefore during reconciliation no nsDef field is set, so no redundant
namespaces are removed by our reconciliation code.
Furthermore, it would only be fixed up automatically if the tree wasn't
added in bottom-up way, or if it had been constructed bottom-up from the
start.
Fix it by setting a flag to remove redundant namespaces in the libxml2
reconciliation call.
Since removing redundant namespaces may have a performance cost, we only do
this after performing a simple check.
Closes GH-11528.
