tree eb6ad5c91374ac8bcc42ee3ec768fac082303d5c
parent ae6d35db140afc303753972447e0125465997fe7
author Pekka Paalanen <pekka.paalanen@collabora.co.uk> 1504015452 +0300
committer Pekka Paalanen <pekka.paalanen@collabora.co.uk> 1507123086 +0300

libweston: ensure backend is not loaded twice

Check and ensure that a compositor can only load one backend
successfully. If a backend fails to load, it is theoretically possible
to try another backend. Once loading succeeds, only destroying the
compositor would allow "unloading" a backend.

If backend init fail, ensure the backend pointer remains NULL to avoid
calling into a half-loaded backend on e.g. compositor destruction.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-by: Ian Ray <ian.ray@ge.com>
Acked-by Daniel Stone <daniels@collabora.com>