[PATCH weston v3 04/11] make the backends compositor-neutral

[Pekka Paalanen]

On Sat, 27 Jun 2015 14:07:44 +0300
Giulio Camuffo <giuliocamuffo at gmail.com> wrote:

> The backends used to have lots of code dealing with weston specific configs.
> To allow them to be used by other compositors with their own configurations
> remove all the usage of weston_config from the backends code and move it
> in weston.c. The backends are now initialized with the new
> weston_compositor_init_backend() function which takes a pointer to a
> weston_backend_config struct. Each backend now installs one header where
> a subclass of weston_backend_config is defined, and the compositor creates
> an instance of the backend-specific config struct and passes it to
> weston_compositor_init_backend().
> This means that the compositor now needs to know about all the backends
> to be able to instantiate them, but no backend specific API such as xcb
> or libdrm leaks through, so there are no new dependencies for the compositor.
> 
> A backend may now set a vfunc pointer to create a new compositor. Not all do

"Compositor" should probably be "output".

> though, and use instead a callback function to configure a new output
> that comes from below the compositor, instead of above it.

I wrote some comments to an earlier thread here:
http://lists.freedesktop.org/archives/wayland-devel/2015-July/023301.html

That is my basis for evaluating this patch.

> ---
>  Makefile.am               |  21 ++
>  src/compositor-drm.c      | 163 +++++--------
>  src/compositor-drm.h      |  77 ++++++
>  src/compositor-fbdev.c    |  66 ++---
>  src/compositor-fbdev.h    |  58 +++++
>  src/compositor-headless.c |  81 +++----
>  src/compositor-headless.h |  47 ++++
>  src/compositor-rdp.c      |  57 +----
>  src/compositor-rdp.h      |  54 +++++
>  src/compositor-rpi.c      |  50 ++--
>  src/compositor-rpi.h      |  51 ++++
>  src/compositor-wayland.c  | 222 ++++-------------
>  src/compositor-wayland.h  |  58 +++++
>  src/compositor-x11.c      | 166 ++++---------
>  src/compositor-x11.h      |  55 +++++
>  src/compositor.c          |  40 +++-
>  src/compositor.h          |  20 +-
>  src/main.c                | 599 ++++++++++++++++++++++++++++++++++++++++++++--
>  18 files changed, 1283 insertions(+), 602 deletions(-)
>  create mode 100644 src/compositor-drm.h
>  create mode 100644 src/compositor-fbdev.h
>  create mode 100644 src/compositor-headless.h
>  create mode 100644 src/compositor-rdp.h
>  create mode 100644 src/compositor-rpi.h
>  create mode 100644 src/compositor-wayland.h
>  create mode 100644 src/compositor-x11.h

This and the following patch "compositor: remove the weston_config
field from weston_compositor" are doing a lot of things at once. I feel
it is hard to see what is going on.

I'll have a look if we could do the following patch series instead:
- add config infra, but stubbed; everything still relies on
  weston_compositor::config
- convert each backend at a time
- convert each other config user at a time
- remove weston_compositor::config as unused

This way we can convert only the drm-backend at first and see how it
looks like.


Thanks,
pq