c250f602bd
If there are any in-progress transitions on any properties of the
effect, these will cause a crash next time they tick and update, as they
will try to access a `@effects.${effect_name}.${property_name}` property
on the `ClutterActor` which no longer resolves to an effect. In some
cases this will be because `priv->effects` itself is now `NULL` on the
`ClutterActor`.
This can be triggered by rapidly toggling screen time limits on and off
in gnome-shell with a low screen time limit which has already been
reached for the day. It will alternately add a desaturation effect and
fade-in transition, then remove the effect, then the transition will
update and crash.
Avoid this by removing relevant transitions when removing an effect.
Do the same for the other two groups of metas: constraints and actions,
as they will be subject to the same bug (under different reproducer
conditions). And the same for when any of these three meta groups are
cleared, as that could also trigger the same bug.
Signed-off-by: Philip Withnall <pwithnall@gnome.org>
Closes: https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/8168
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4222>
Mutter
Mutter is a Wayland display server and X11 window manager and compositor library.
When used as a Wayland display server, it runs on top of KMS and libinput. It implements the compositor side of the Wayland core protocol as well as various protocol extensions. It also has functionality related to running X11 applications using Xwayland.
When used on top of Xorg it acts as a X11 window manager and compositing manager.
It contains functionality related to, among other things, window management, window compositing, focus tracking, workspace management, keybindings and monitor configuration.
Internally it uses a fork of Cogl, a hardware acceleration abstraction library used to simplify usage of OpenGL pipelines, as well as a fork of Clutter, a scene graph and user interface toolkit.
Mutter is used by, for example, GNOME Shell, the GNOME core user interface, and by Gala, elementary OS's window manager. It can also be run standalone, using the command "mutter", but just running plain mutter is only intended for debugging purposes.
Contributing
To contribute, open merge requests at https://gitlab.gnome.org/GNOME/mutter.
It can be useful to first look at the GNOME Handbook and the documentation and API references below first.
Documentation
- Coding style and conventions
- Git conventions
- Code overview
- Building and Running
- Debugging
- Monitor configuration
- Multi-GPU
API Reference
- Meta: https://mutter.gnome.org/meta/
- Clutter: https://mutter.gnome.org/clutter/
- Cogl: https://mutter.gnome.org/cogl/
- Mtk: https://mutter.gnome.org/mtk/
Meetings
There are recurring meetings to discuss development of GNOME Shell, mutter and related components.
License
Mutter is distributed under the terms of the GNU General Public License, version 2 or later. See the COPYING file for detalis.