Re: [Libguestfs] GObject bindings overview

There are a couple of points in here I'm still not 100% happy with. Specifically the handling of FBuffer and the Cancellable flag. Both are explained below. I'm interested in suggestions. A parallel struct is created for each libguestfs struct type. A boxed type is created for each parallel struct. It's field types are all mapped trivially to gobject basic types (e.g. gchar *, gint32) except FBuffer. FBuffer is mapped as: guint8 *<field> guint32 <field>_size Unfortunately I can see no way to attach annotation to these fields, so the bindings do not appreciate that these fields are related. I'm not happy with this at all, so I may try manual tweaking of the .gir to see if we can turn these into a single returned array where possible.

Cancellation: ************* Certain apis are cancellable. These all take a GCancellable as the final argument before GError **. This can be passed NULL if cancellation is not required. While I have written cancellation, I have not yet tested it *at all* other than it compiles and works correctly when NULL is passed in. We recently made Cancellable an explicit flag whereas before it was implicit if the api had a FileIn or FileOut argument. This means it is now possible to break the GObject api without breaking the C api with the addition of a Cancellable flag. What potential solutions are there to this problem? I can see: • Live with breaking the GObject api if it ever comes up. • Never add Cancellable to an existing api. • Automatically add a GCancellable argument to all GObject apis, just in case.