Due to being a compositor, kwin has to conform to some certain
interfaces. It means a lot of virtual functions and function tables to
integrate with C APIs. Naturally, we not always want to use every
argument in such functions.
Since we get -Wunused-parameter from -Wall, we have to plumb those
unused arguments in order to suppress compiler warnings at the moment.
However, I don't think that extra work is worth it. We cannot change or
alter prototypes in any way to fix the warning the desired way. Q_UNUSED
and similar macros are not good indicators of whether an argument is
used too, we tend to overlook putting or removing those macros. I've
also noticed that Q_UNUSED are not used to guide us with the removal no
longer needed parameters.
Therefore, I think it's worth adding -Wno-unused-parameter compiler
option to stop the compiler producing warnings about unused parameters.
It changes nothing except that we don't need to put Q_UNUSED anymore,
which can be really cumbersome sometimes. Note that it doesn't affect
unused variables, you'll still get a -Wunused-variable compiler warning
if a variable is unused.
Unfortunately, we cannot just simply unset the wl_global's user data.
The compositor still needs to process client requests after the global
has been removed, for example bind requests or the requests that create
new resources.
CCBUG: 435258
Destroying a global leads to a race on the client. If a client binds
at just the wrong moment they will use an invalid ID and cause a
protocol error. The current best thing to do is to announce the removal
then remove the global (and thus the ID) only after a delay. Non-ideal,
but better than nothing.
Pragmatically this affects only:
Blur/Contrast/Slide/Output/OutputDevice
See https://gitlab.freedesktop.org/wayland/wayland/issues/10 for more.
If a Wayland protocol deals with regions, they will be exposed as
QRegion objects in public API. Therefore, it makes sense to make
RegionInterface private as it's an implementation detail and it's
not intended to be used in public api.
The corresponding test was dropped because the CompositorInterface
no longer emits a signal to indicate that a wl_region has been created.
It should be also noted that wl_region stuff is already tested via
other means, e.g. surface damage, etc.
s_version is used only to initialize a global so there is no point for
storing protocol version in a static member field and use funky syntax
in the cpp file to initialize it. This change also simplifies the code.
Summary:
There is a race condition in the following situation:
- Server creates a global
- Client binds to that global (making a new resource for that
global)
Simultaneously:
- The client uses this resource
- The server deletes the global
This was fixed for Blur, but as mention in that commit can also happen here.
Code is effectively a copy and paste from e8850b014c
Test Plan: Unit test. Booted normal session
Reviewers: #plasma
Subscribers: plasma-devel, #frameworks
Tags: #plasma_on_wayland, #frameworks
Differential Revision: https://phabricator.kde.org/D7885
Summary:
Destroying the ContrastInterface on the server side before the client has
a chance to cleanup results in a protocol error:
wl_display@1: error 0: invalid object 7
Which would terminate the client. If we would not destroy the resource,
but only delete the ContrastInterface it could result in
heap-use-after-free.
So just don't do anything, the client needs to cleanup which will result
in the ContrastInterface being deleted.
Reviewers: #plasma
Subscribers: plasma-devel
Tags: #plasma
Differential Revision: https://phabricator.kde.org/D1709
Summary:
This change standardizes the behavior regarding the destructor request.
The destructor should destroy the resource and nothing else. The
Wayland library invokes the static unbind method once the resource is
destroyed. The implementation provided by Resource::Private::unbind
triggers a delete later on the Resource. So there is no need to trigger
a deleteLater from the destructor request callback.
This change adds a generic implementation to Resource::Private which is
now used by all inheriting classes replacing the custom implementations.
Test Plan:
For a few Resources the test is extended to ensure that the Resource
gets deleted on server side.
Reviewers: #plasma
Subscribers: plasma-devel
Tags: #plasma
Differential Revision: https://phabricator.kde.org/D1679
Summary:
Not needed as the dtor of the Resource ensures that the wl_resource
gets destroyed.
Reviewers: #plasma
Subscribers: plasma-devel
Tags: #plasma
Differential Revision: https://phabricator.kde.org/D1680
Follows a useful change added in the kwaylandScanner tool the
s_version becomes part of the Private class.
Also fixes the related generation in the tool.
