[Pkg-swan-devel] Bug#1020495: Bug#1020495: Error: unable to load VPN connection editor - on Identity tab at Gnome Network manager VPN

[Tobias Brunner]

>> That's because the settings app uses GTK 4, while `nm-connection-editor`
>> still uses GTK 3.  In order for the strongSwan plugin to work with GTK
>> 4, it has to be built with `--with-gkt4`.  That creates an additional
>> version of the editor that's linked against GTK 4 (besides the one
>> linked against GTK 3).  These are actually two shared libraries that are
>> loaded dynamically at runtime by the main editor plugin depending on
>> whether it's loaded by a GTK 3 or 4 application.
> 
> Ah, thanks for the information. So that means at some point we should enable
> that in our build I guess.

Yep.  Is it a problem if the package depends on both libgtk-3-0 and 
libgtk-4-0 as well as libnma0 and libnma-gtk4-0?  Or does that require a 
separate package for the GTK 4 version?  Or is there some metadata magic 
that can make it work with GTK 3 and/or GTK 4 (at least one, but does 
not require both)?

Technically, as I mentioned before, the main plugin 
(libnm-vpn-plugin-strongswan.so), that's the one actually loaded by NM 
or any other GUI, does not depend on libgtk or libnma.  However, 
depending on whether it was loaded by an application that uses GTK 3 or 
GTK 4 (it uses dlsym() to search for a GTK3-only symbol), it then 
dynamically loads either libnm-vpn-plugin-strongswan-editor.so or 
libnm-gtk4-vpn-plugin-strongswan-editor.so via dlopen(), which are 
linked against the corresponding libgtk/libnma.  So I guess one could 
argue that neither is a hard dependency for the package as the 
application that loads the plugin must have such a dependency on either 
version of these libraries anyway (at least libgtk, not sure about 
libnma).  So maybe those dependencies could also be omitted?

Regards,
Tobias