dbusxml2qt3 do not exit with error when root node name is not specified #25

Basic information

TDE version: R14.1.0
Distribution: Debian Buster
Hardware: amd64

Description

Introspection Data Format states that only root node name can be omitted

Only the root element can omit the node name, as it's known to be the object that was introspected. If the root does have a name attribute, it must be an absolute object path. If child have object paths, they must be relative.

If a child has any sub-elements, then they must represent a complete introspection of the child. If a child is empty, then it may or may not have sub-elements; the child must be introspected in order to find out. The intent is that if an object knows that its children are "fast" to introspect it can go ahead and return their information, but otherwise it can omit it.

I suggest we return 0 (exit(0)) in such case.

Steps to reproduce

generate interfaces from root node without a name
echo $? => 3

Screenshots

Hi Emanoil, I am not sure I understand what the problem is here exactly.
Could you explain in more detail?

The problem is that it should not exit with error, because it is a valid use case.

So if you want to generate the interfaces you can do this without dbusxml2qt3 exiting with error and if you want a code for the root node you can generate with -n -c.

Returning 3 breaks cmake in a legitim use case.

The error message is OK (should be interpreted as warning).

I came upon this when trying to use automated interface generated.

When using dbusxml2qt3 on the command line no one is checking the exit code.

Hi Emanoil, first of all thanks for the explanation.

Say you have a "test.xml" file with a root node without a name.

If you run

dbusxml2qt3 test.xml

you get the error you described. This happens because you are trying to generate a class node and there is no class name specified (either in the .xml file or on CLI) so it is not possible to continue correctly. The program is exiting because it is invoked incorrectly.

If you run

dbusxml2qt3 -c testNode test.xml

the interfaces and the class node are correctly generated and there is no error.

If you run

dbusxml2qt3 test.xml -i

the interfaces are correctly generated and there is no error, since you are not asking to generate any class node.

In light of the above, the fix you proposed in #26 is wrong and not necessary in my opinion. So if you agree with me, I will close that PR.

One thing where dbusxml2qt3 could be improved, is the way parameters are passed. Invoking

dbusxml2qt3 test.xml -i

is weird. It should be something like one of the following:

dbusxml2qt3 -i <interface name> test.xml
dbusxml2qt3 -I test.xml
dbusxml2qt3 -i -- test.xml

where the options are specified before the xml file and we use a mean to specify when the interface name is not required (otherwise "dbusxml2qt3 -i test.xml" would use test.xml as an interface name :-( ).

What do you think?

Hi Michele,

you might be correct, I don't know for sure. TBH I was expecting the opposite as in the code it says "generateAll", means it should generate all.

If I supply -i it will generate only the interfaces, if I supply only -p it will generate only the proxies. So I was expecting by invoking the command without parameters to create whatever it can and subsequentially run it with -n -c if I would need a RootNode class to refer to all interfaces included.

regarding the arguments indeed it can be improved ...

Leave it in WIP, I will play a bit more with that.

So I was expecting by invoking the command without parameters to create whatever it can

Hi Emanoil, it may be a matter of interpretation. Without parameters it is more like "try to generate all" which of course includes a class node as well. When the root node has a name attribute, this works fine. If there is no node attribute and none is provided on the command line, either we skip the class node in full (meaning we don't exit, we simply skip the class node) or we keep the current behavior.

I see in the usage of dbusxml2qt3 that it says "Generates as much as possible, i.e. interfaces, proxies and, if a node name is specified in 'myinterface.xml', the node files", so perhaps you can come up with a PR where if no class node exists, we skip the class node and we simply print a warning message.

Hi Michele,

this sounds like a great idea and is exactly what I was looking for and what was confusing me, because a node without a name is assumed to be a root node. In such case if desired run dbusxml2qt3 a second time for that purpose with node and class arguments.

I'll do a new PR when ready

thanks and regards

no problem. I will close #26 as invalid. Just create a new one when you are done 😉

IMO PR#27 seems to be working as suggested

Solved by PR #27.