Commit Graph

130 Commits

Author SHA1 Message Date
Jonas Ådahl
e020fdfddf Introduce mostly empty MetaContext type
This type is intended to replace the scattered functions used to
configure how the Mutter compositor is run. It currently doesn't do
anything, and only has a human readable name, intended to be set to e.g.
"GNOME Shell".

It's an abstract type, and is intended to be used via either a future
`MetaContextMain` for real display server use cases, and a
`MetaContextTest` for test cases.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1861>
2021-07-15 10:43:28 +02:00
Carlos Garnacho
ec390b68c5 wayland: Implement the xdg-activation protocol
This protocol implements the IPC necessary to focus application
windows across launcher/launchee. Add support for it.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1845>
2021-07-09 09:34:28 +00:00
Carlos Garnacho
2115debd09 build: Add xdg-activation to build
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1845>
2021-07-09 09:34:28 +00:00
Carlos Garnacho
256939cb84 build: Add support for "staging" wayland protocols
These come in a different folder, with no stable/unstable nomenclature.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1845>
2021-07-09 09:34:28 +00:00
Jonas Ådahl
ee8c252a8c native: Add device pool for tracking device file descriptors
This practically does the same thing as part of MetaLauncher, except
with added thread safety and caching. For example, opening the same file
a second time will return the same MetaDeviceFile, and only once all
acquired MetaDeviceFile's are released, will the file descriptor be
closed and control of the device released.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1828>
2021-07-07 21:03:25 +02:00
Jonas Ådahl
18d670e69f backends: Introduce MetaIdleManager
This object takes over the functionality of meta-idle-monitor-dbus.c,
meta-idle-monitor.c and meta-backend.c, all related to higher level
management of idle watches etc.

The idle D-Bus API is changed to be initialized by the backend instead
of MetaDisplay, as it's more of a backend functionality than what
MetaDisplay usually deals with.

It also takes over the work of implementing "core" idle monitors. The
singleton API is replaced with thin wrapper functions on the backend.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1859>
2021-05-18 13:19:36 +00:00
Jonas Ådahl
af501ac472 prefs: Make init function private
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1833>
2021-05-17 16:08:42 +00:00
Jonas Ådahl
8867b11e19 launcher: Use gnome.gdbusgen and add prefix to generated API
This is more in line with how generated D-Bus boilerplate work, lets
stay consistent.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1820>
2021-04-14 12:53:25 +00:00
Jonas Ådahl
74ab2120fa screen-cast/session: Introduce RecordVirtual D-Bus API
The new RecordVirtual API creates a virtual monitor, i.e. a region of
the stage that isn't backed by real monitor hardware. It's intended to
be used by e.g. network screens on active sessions, virtual remote
desktop screens when running headless, and scenarios like that.

A major difference between the current Record* API's is that
RecordVirtual relies on PipeWire itself to negotiate the refresh rate
and size, as it can't rely on any existing monitor, for those details.

This also means that the virtual monitor is not created until the stream
negotiation has finished and a virtual monitor resolution has been
determined.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Jonas Ådahl
1818d21da5 Introduce virtual monitors
Virtual monitors are monitors that isn't backed by any monitor like
hardware. It would typically be backed by e.g. a remote desktop service,
or a network display.

It is currently only supported by the native backend, and whether the
X11 backend will ever see virtual monitors is an open question. This
rest of this commit message describes how it works under the native
backend.

Each virutal monitor consists of virtualized mode setting components:

 * A virtual CRTC mode (MetaCrtcModeVirtual)
 * A virtual CRTC (MetaCrtcVirtual)
 * A virtual connector (MetaOutputVirtual)

In difference to the corresponding mode setting objects that represents
KMS objects, the virtual ones isn't directly tied to a MetaGpu, other
than the CoglFramebuffer being part of the GPU context of the primary
GPU, which is the case for all monitors no matter what GPU they are
connected to. Part of the reason for this is that a MetaGpu in practice
represents a mode setting device, and its CRTCs and outputs, are all
backed by real mode setting objects, while a virtual monitor is only
backed by a framebuffer that is tied to the primary GPU. Maybe this will
be reevaluated in the future, but since a virtual monitor is not tied to
any GPU currently, so is the case for the virtual mode setting objects.

The native rendering backend, including the cursor renderer, is adapted
to handle the situation where a CRTC does not have a GPU associated with
it; this in practice means that it e.g. will not try to upload HW cursor
buffers when the cursor is only on a virtual monitor. The same applies
to the native renderer, which is made to avoid creating
MetaOnscreenNative for views that are backed by virtual CRTCs, as well
as to avoid trying to mode set on such views.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Jonas Ådahl
ee4e78b100 kms: Add way to run without mode setting
Currently our only entry point for DRM devices is MetaKms*, but in order
to run without being DRM master, we cannot use /dev/dri/card*, nor can
we be either of the existing MetaKmsImplDevice implementation (legacy
KMS, and atomic KMS), as they both depend on being DRM master.

Thus to handle running without being DRM master (i.e. headless), add a
"dummy" MetaKmsImplDevice implementation, that doesn't do any mode
setting at all, and that switches to operate on the render node, instead
of the card node itself.

This means we still use the same GBM code paths as the regular native
backend paths, except we never make use of any CRTC backed onscreen
framebuffers.

Eventually, this "dummy" MetaKmsImplDevice will be replaced separating
"KMS" device objects from "render" device objects, but that will require
more significant changes. It will, however, be necessary for e.g. going
from being headless, only having access to a render node, to turning
into a real session, with a seat, being DRM master, and having access to
a card node.

This is currently not hooked up, but will be in a later commit.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Jonas Ådahl
0786f44b0b seat/impl: Make it possible to run without libinput
Add a flag to MetaSeatNative and MetaSeatImpl that tells it not to
attempt to create a libinput context. This is intended to be used when
mutter is to run headless, as in without any input devices other than
virtual ones.

Currently not hooked up.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Jonas Ådahl
c4a422bc24 crtc/kms: Add an abstract MetaCrtcNative that sits under MetaCrtcKms
There is going to me another non-abstract MetaCrtcNative type, just as
there will be for MetaOutputNative.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Jonas Ådahl
fd4ea67b27 native: Add abstract MetaOutputNative object
MetaOutputKms is made to inherit from this, but it doesn't do anything
special yet.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Jonas Ådahl
3091cd89dc native: Rename MetaMonitorManagerKms to MetaMonitorManagerNative
We'll sooner or later start managing not only KMS backend monitors, but
virtual / remote ones too.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1698>
2021-03-12 15:09:45 +00:00
Marco Trevisan (Treviño)
ccbdf91776 backends/x11: Add dummy input-settings implementation
The nested backend may need to have an input setting implementation,
while we don't want to change the host settings (re-using an X11 input
settings) we can add a dummy implementation, until something more
complex is needed.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1769>
2021-03-10 13:56:54 +00:00
Ivan Molodetskikh
dccc60ec3e wayland: Implement stub presentation-time
The presentation-time protocol allows surfaces to get accurate
timestamps of when their contents were shown on screen.

This commit implements a stub version of the protocol which correctly
discards all presentation feedback objects (as if the surface contents
are never shown on screen). Subsequent commits will implement sending
the presented events to surfaces shown on screen.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1484>
2021-03-08 09:48:11 +00:00
Ivan Molodetskikh
2f4027200f Generate presentation-time files
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1484>
2021-03-08 09:48:11 +00:00
Ivan Molodetskikh
dae089f79e clutter: Remove CLUTTER_ENABLE_EXPERIMENTAL_API
It is no longer used anywhere.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1707>
2021-02-05 17:05:19 +00:00
Jonas Ådahl
a220506bf7 remote-desktop: Add dummy remote selection source
It doesn't yet fetch data from the remote desktop session, but hooks up
correctly.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1552>
2021-02-05 16:44:27 +00:00
Jonas Ådahl
3e4ece50d3 renderer/native: Move out CoglOnscreen code to separate file
To get meta-renderer-native.c down to a bit more managable size, and to
isolate "onscreen" functionality from other (at least partly), move out
the things related to CoglOnscreen to meta-onscreen-native.[ch].

A couple of structs are moved to a new shared header file, as
abstracting those types (e.g. (primary, secondary) render devices) will
be dealt with later.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1514>
2021-01-30 09:11:45 +00:00
Jonas Ådahl
fb38c451b5 kms: Add atomic MetaKmsImplDevice backend
This adds a MetaKmsImplDevice backend using atomic drmMode* API in constrast to
non-atomic legacy drmMode* API used in MetaKmsImplDeviceSimple.

This has various behavioral differences worth noting, compared to the
simple backend:

 * We can only commit once per CRTC per page flip.

This means that we can only update the cursor plane once. If a primary
plane composition missed a dead line, we cannot commit only a cursor
update that would be presented earlier.

 * Partial success is not possible with the atomic backend.

Cursor planes may fail with the simple backend. This is not the case
with the atomic backend. This will instead later be handled using API
specific to the atomic backend, that will effectively translate into
TEST_ONLY commits.

For testing and debugging purposes, the environment variable
MUTTER_DEBUG_ENABLE_ATOMIC_KMS can be set to either 1 or 0 to
force-enable or force-disable atomic mode setting. Setting it to some
other value will cause mutter to abort().

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/548
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>
2021-01-22 16:47:08 +00:00
Jonas Ådahl
84bde805fe native: Consolidate DRM buffer management to MetaDrmBuffer types
This commit consolidates DRM buffer management to the MetaDrmBuffer
types, where the base type handles the common functionality (such as
managing the framebuffer id using drmModeAdd*/RMFb()), and the sub types
their corresponding type specific behavior.

This means that drmModeAdd*/RmFB() handling is moved from meta-gpu-kms.c
to meta-drm-buffer.c; dumb buffer allocation/management from
meta-renderer-native.c.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>
2021-01-22 16:47:08 +00:00
Jonas Ådahl
7137bd4b10 kms: Move impl backend inherit MetaKmsImplDevice instead of MetaKmsImpl
This allows different types of backends to coexist, would e.g. one
device support atomic but another not.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>
2021-01-22 16:47:08 +00:00
Jonas Ådahl
f0d3201dab kms: Add MetaKmsMode abstraction
This contains a copy of a drmModeModeInfo, describing a mode. It also
has an unused pointer to the impl device it is associated with. It'll
later be used to get a blob ID for the mode.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>
2021-01-22 16:47:08 +00:00
Carlos Garnacho
64d5e8a9bd backends/native: Drop MetaEventNative
This doesn't really hold anything now, so we can stop trying to
copy these across events.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1623>
2020-12-08 15:37:38 +00:00
Carlos Garnacho
59059e1730 backends/native: Spin MetaSeatImpl off MetaSeatNative
Move most of the functional bits (those meant to run on a standalone
thread) to a MetaSeatImpl object. This object is managed by the MetaSeatImpl
and not exposed outside the friend MetaSeatNative/MetaInputDeviceNative/
MetaInputSettings classes.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
2020-11-27 15:14:33 +00:00
Carlos Garnacho
0c1d48bd08 backends: Add simple object to delegate logical monitor layout queries
This object can be passed to random places, and be trusted to remain unchanged
till replaced. Makes it an ideal replacement for MetaMonitorManager across
threads.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
2020-11-27 15:14:33 +00:00
Carlos Garnacho
5f30d1b8ac backends: Split pad action mapping to a separate object
This now lives in the core, and will get updated from events in the
UI thread.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
2020-11-27 15:14:33 +00:00
Carlos Garnacho
7a2a2445c3 backends: Remove x/y arguments from MetaCursorTracker::cursor-moved
Make this signal a hint, the actual coordinates should be queried to the
cursor tracker, the device, the seat... There's enough options.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
2020-11-27 15:14:33 +00:00
Carlos Garnacho
8a8d47725c backends: Delegate pointer confinements to an impl object
Split pointer confinements in 2 objects, one set from the upper layers
containing its definition, and another managed by the backend that
applies it.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
2020-11-27 15:14:33 +00:00
Florian Müllner
f481cbfa16 plugin: Drop version information
Mutter itself is versioned now, so passing the version information
to the plugin is redunant now: The version is already determined by
linking to a particular API version (gnome-shell) or by installing
to a versioned plugin path (external plugins).

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1473
2020-10-06 15:14:34 +02:00
Carlos Garnacho
4e9a2e4799 build: Do not provide built sources as libmutter_dep sources
This is essentially a revert of
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/326. This commit
had the unintended side effect that the built sources are actually
rebuilt for every individual user of libmutter_dep. With there being more
tests and generated files, the number of targets to build is increasing
squarely.

Not doing this reduces the number of targets from 2044 to 874, thus
saving man hours and CI burnt cycles in the long run. There's the slight
risk of reintroducing the random build breaks, but mutter is essentially
doing as suggested at https://github.com/mesonbuild/meson/issues/1084
(the only difference being addressed in the previous commit), so meson
ought to behave as expected.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1458
2020-09-30 18:44:33 +00:00
Carlos Garnacho
4dbf2dea05 build: Build libmutter using sources as positional arguments
The "sources" keyword argument does not seem documented at
https://mesonbuild.com/Reference-manual.html#shared_library or
the related objects.

It may work, but let's use meson as intended.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1458
2020-09-30 18:44:33 +00:00
Georges Basile Stavracas Neto
661fe7769d backends/native: Move pixel format helper to separate file
The pixel format helper will be reused by the next commits, and
it doesn't make sense to simply expose it as MetaRendererNative
API.

Move it to a separate file.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1421
2020-09-01 13:05:24 -03:00
Jonas Ådahl
3abbfef66e cursor-tracker: Add X11 cursor tracker backend
The intention is to use this to actively track the cursor position given
a fixed interval when needed, e.g. when screen casting.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1391
2020-08-05 11:11:38 +02:00
Sergio Costas
f894f5cc13 wayland: Add API to launch trusted clients
Allowing code from inside mutter to create a child process and
delegate on it some of its tasks is something very useful. This can
be done easily with the g_subprocess and g_subprocess_launcher classes
already available in GLib and GObject.

Unfortunately, although the child process can be a graphical program,
currently it is not possible for the inner code to identify the
windows created by the child in a secure manner (this is: being able
to ensure that a malicious program won't be able to trick the inner
code into thinking it is a child process launched by it).

Under X11 this is not a problem because any program has full control
over their windows, but under Wayland it is a different story: a
program can't neither force their window to be kept at the top (like a
docker program does) or at the bottom (like a program for desktop icons
does), nor hide it from the list of windows. This means that it is not
possible for a "classic", non-priviledged program, to fulfill these
tasks, and it can be done only from code inside mutter (like a
gnome-shell extension).

This is a non desirable situation, because an extension runs in the
same main loop than the whole desktop itself, which means that a
complex extension can need to do too much work inside the main loop,
and freeze the whole desktop for too much time. Also, it is important
to note that javascript doesn't have access to fork(), or threads,
which means that, at most, all the parallel computing that can do is
those available in the _async calls in GLib/GObject.

Also, having to create an extension for any priviledged graphical
element is an stopper for a lot of programmers who already know
GTK+ but doesn't know Clutter.

This patch wants to offer a solution to this problem, by offering a
new class that allows to launch a trusted child process from inside
mutter, and make it to use an specific UNIX socket to communicate
with the compositor. It also allows to check whether an specific
MetaWindow was created by one of this trusted child processes or not.

This allows to create extensions that launch a child process, and
when that process creates a window, the extension can confirm in a
secure way that the window really belongs to that process
launched by it, so it can give to that window "superpowers" like
being kept at the bottom of the desktop, not being listed in the
list of windows or shown in the Activities panel... Also, in future
versions, it could easily implement protocol extensions that only
could be used by these trusted child processes.

Several examples of the usefulness of this are that, with it, it
is possible to write programs that implements:

- desktop icons
- a dock
- a top or bottom bar
...

all in a secure manner, avoiding insecure programs to do the same.
In fact, even if the same code is launched manually, it won't have
those privileges, only the specific process launched from inside
mutter.

Since this is only needed under Wayland, it won't work under X11.

Fixes https://gitlab.gnome.org/GNOME/mutter/issues/741
2020-08-04 08:42:29 +00:00
Jonas Ådahl
14cd78a016 screen-cast: Add screen cast flag to streams
Intended to be used to pass state from screen cast clients down the
line. The first use case will be a boolean whether a screen cast is a
plain recording or not, e.g. letting the Shell decide whether to use a
red dot as the icon, or the generic "sharing" symbol.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1377
2020-07-30 09:51:16 +02:00
Christian Hergert
2c08eb6d16 build: bump ABI to sysprof-capture-4
GLib will now be linking against sysprof-capture-4.a. To support that,
sysprof had to remove the GLib dependency from sysprof-capture-4 which
had the side-effect of breaking ABi.

This bumps the dependency and includes a fallback to compile just the
libsysprof-capture-4.a using a subproject wrap.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1352
2020-07-28 11:13:30 -07:00
Jonas Ådahl
e089e53b24 crtc-kms: Make KMS CRTC mode a type inheriting MetaCrtcMode
It carries the drmModeModeInfo copy in it's instance struct, instead of
the `driver_private` it was using before.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1287

This version of the commit includes fixes from:

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1305
2020-06-11 09:20:16 +00:00
Georges Basile Stavracas Neto
49408e8f9f Revert "crtc-kms: Make KMS CRTC mode a type inheriting MetaCrtcMode"
This reverts commit 09078762a, which breaks Mutter.
2020-06-10 23:11:21 -03:00
Jonas Ådahl
09078762ac crtc-kms: Make KMS CRTC mode a type inheriting MetaCrtcMode
It carries the drmModeModeInfo copy in it's instance struct, instead of
the `driver_private` it was using before.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1287
2020-06-10 18:54:51 +00:00
Jonas Ådahl
980ece9a4b crtc: Move out MetaCrtcMode into its own file
It's somewhat annoying to have two very closely named types in the same
file. It's also about to grow some, so better move it to its own file.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1287
2020-06-10 18:54:51 +00:00
Georges Basile Stavracas Neto
a1b3d1a2a7 Introduce MetaBackgroundContent
MetaBackgroundContent is a ClutterContent implementation
that can render a background to any attached actor. Right
now, it preserves all the properties and the rendering
model of MetaBackgroundActor.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1302
2020-06-09 17:07:02 -03:00
Peter Hutterer
f712387325 compositor: use XDG_CONFIG_HOME as initial lookup path for xkb
Using XDG_CONFIG_HOME allows users to place their keyboard configuration into
their home directory and have them loaded automatically.
libxkbcommon now defaults to XDG_CONFIG_HOME/xkb/ first, see
https://github.com/xkbcommon/libxkbcommon/pull/117

However - libxkbcommon uses secure_getenv() to obtain XDG_CONFIG_HOME and thus
fails to load this for the mutter context which has cap_sys_nice.
We need to manually add that search path as lookup path.

As we can only append paths to libxkbcommon's context, we need to start with
an empty search path set, add our custom path, then append the default search
paths.

The net effect is nil where a user doesn't have XDG_CONFIG_HOME/xkb/.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/936
2020-06-08 11:29:30 +00:00
Carlos Garnacho
2becb3dd29 wayland: Add support for wayland-protocols primary selection protocol
This protocol was added some time ago. Supporting it fell through the
cracks. Add new data device/source/offer implementations for it,
interoperation between primary selection protocols (and X11 primary
selection for that matter) comes for free.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/943

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1255
2020-05-13 18:27:46 +02:00
Carlos Garnacho
55f5177fe0 build: Build scaffolding for primary-selection wayland protocol
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1255
2020-05-13 18:18:18 +02:00
Carlos Garnacho
037b68ab8e wayland: Rename gtk primary protocol files to "legacy"
We want to make room for the wayland-protocols primary selection
protocol. Rename our private protocol as "legacy".

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1255
2020-05-13 18:18:14 +02:00
Jonas Ådahl
c4535fdf85 screen-cast: Add RecordArea for screen cast arbitrary area
It takes coordinates in stage coordinate space, and will result in
a screen cast stream consisting of that area, but scaled up by the scale
factor of the view that overlaps with the area and has the highest scale
factor.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1207
2020-04-23 14:45:53 +00:00
Jonas Dreßler
551a57ed7f Add read-only anonymous file abstraction MetaAnonymousFile
Add MetaAnonymousFile, an abstraction around anonymous read-only files.
Files can be created by calling meta_anonymous_file_new(), passing the
data of the file. Subsequent calls to meta_anonymous_file_open_fd()
return a fd that's ready to be sent over the socket.

When mapmode is META_ANONYMOUS_FILE_MAPMODE_PRIVATE the fd is only
guaranteed to be mmap-able readonly with MAP_PRIVATE but does not
require duplicating the file for each resource when memfd_create is
available. META_ANONYMOUS_FILE_MAPMODE_SHARED may be used when the
client must be able to map the file with MAP_SHARED but it also means
that the file has to be duplicated even when memfd_create is available.

Pretty much all of this code was written for weston by Sebastian Wick,
see https://gitlab.freedesktop.org/wayland/weston/merge_requests/240.

Co-authored-by: Sebastian Wick <sebastian@sebastianwick.net>

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1012
2020-04-21 17:52:08 +02:00