[SOLVED] Add field to XmlElement without memory leak

Audio Plugins
1

I’m trying to add a separate field to the XML-binary data in getStateInformation(), which is not part of the AudioValueTree:

void OdinAudioProcessor::getStateInformation(MemoryBlock &destData) {
	auto state = m_value_tree.copyState();
	std::unique_ptr<XmlElement> xml(state.createXml());

	// add separate field  
	std::unique_ptr<XmlElement> test_element 
			= std::make_unique<XmlElement>(XmlElement("TestElement"));
	test_element->setAttribute("data", "Hello JUCE!");
	xml->addChildElement(test_element.get());

	copyXmlToBinary(*xml, destData);
}

As I use a unique_ptr, the data is destroyed after this function call, which causes a segfault. When using a plain pointer, allocating memory with new, everything works out (provided I don’t use delete). But in this case I would have a memory leak, since I never deallocate the memory…

Anybody knows how to resolve this situation? Why does copyXmlToBinary() keep pointers in the first place instead of resolving to the actual data?

2

There will be no memory leak with a raw pointer/new, the XmlElement transfers ownership of the passed in child element to itself. If there was a memory leak, the Juce memory leak detection would have caught that.

https://docs.juce.com/master/classXmlElement.html#a9b9735dd8a98c5af71db4c532cd10a1c

1 Like
3

Awesome!

Thanks for the quick reply!