libxml: Fix some deprecations regarding input buffer/parser handling

[ndossche]

This is the first batch of changes to migrate away from deprecated APIs, fixes some deprecation warnings.

[devnexen]

Is there more to it than deprecated fields ?

[devnexen]

seems worth it to fix in the same move the input buffer part IMHO (~line 594)

[ndossche]

Is there more to it than deprecated fields ?

Here we can easily avoid some of the direct field accesses by using (new) public APIs.
There's a remaining deprecation in the ext/libxml/libxml.c file that requires more complex changes.

There is also an issue I opened on the libxml repo about a deprecation that I see no full replacement for: https://gitlab.gnome.org/GNOME/libxml2/-/issues/1017

[ndossche]

seems worth it to fix in the same move the input buffer part IMHO (~line 594)

That requires more thinking as that function needs to return a xmlParserInputBufferPtr

[devnexen]

Is there more to it than deprecated fields ?

Here we can easily avoid some of the direct field accesses by using (new) public APIs. There's a remaining deprecation in the ext/libxml/libxml.c file that requires more complex changes.

There is also an issue I opened on the libxml repo about a deprecation that I see no full replacement for: https://gitlab.gnome.org/GNOME/libxml2/-/issues/1017

gosh :)

[devnexen]

alright then